Abstract

The device characteristics of organic light-emitting devices based on tris-(8-hydroxyqunoline) aluminum devices with LiF/Mg:Ag/Ag cathodes were investigated. The devices with Mg:Ag/Ag, LiF/Al and Al-only cathodes were also fabricated in the same run for comparison. Similar to the LiF/Al cathodes, the LiF/Mg:Ag/Ag cathode greatly improved the performance of the device over the Mg:Ag/Ag cathode. A LiF layer of 0.5 nm significantly enhanced the electron injection and resulted in lower turn-on voltage and increased device efficiency. The turn-on voltage of the device with 0.5 nm LiF as buffered layer is as low as 2.8 V. At injection current density of 20 mA/cm2, the current efficiency and power efficiency of the device is 5.56 cd/A and 1.94 lm/W, respectively. Compared to the device with Mg:Ag/Ag only cathode, the turn-on voltage is 1.6 V lower, the current efficiency improved by 75 %, and power efficiency is almost double. The performance of the device is also much improved over the device with LiF/Al cathode.

©2005 Optical Society of America

1. Introduction

The applications of organic electroluminescent materials to organic light-emitting diodes (OLED) have become increasingly important in recent years because of their technological potential to multi-color self-luminous flat-panel displays. The key advantages of OLED are the capability of a wide range of emission colors, low-voltage operation (< 3V), high-efficiency, wide-viewing angle, high-contrast, potential for low-cost manufacturing, large-area multi-color displays and mechanical flexibility. Fueled by great commercial interest, recent years it have seen an explosive growth in the research and development activities leading to OLED production by several major electronics companies. While OLED products have already appeared, challenges still remain to resolve the important issues concerning reliability, chromaticity, contrast, and luminous efficiencies for OLED.

Lithium fluoride is an insulating inorganic material with large band gap energy of 12 eV. LiF was first introduced into OLED by Hung et al. in 1997 [1]. By inserting a very thin layer (0.5 nm or 1.0 nm) LiF between a tris-(8-hydroxyquinoline) aluminum (Alq3) layer and an Al cathode, the electroluminescent (EL) performance of the OLED had been more significantly improved compared to the devices with Al-only and Mg0.9Ag0.1 alloy cathode. Thereafter, many insulating inorganic materials such as MgF2 [2], CaF2 [3], CsF [4], MgO [1], Al2O3 [5], NaCl [6], NaSt [7], were extensive studied, the optimal thickness of the these insulating layers was usually less than 1.0 nm. In the case of LiF/Al cathode, there are a number of mechanisms that were proposed for enhanced electron injection, including tunneling effect [1], band bending at the organic/metal interface [8], lowering of the work function of Al [9], formation of dipoles at Alq3/LiF/Al interface [10], and LiF dissociation with released Li atoms and subsequent reaction with Alq3 to generate Alq3 anions [11]. Most of these researches are focused on modified high work function metals, such as Al [1, 814], Ag [15] cathode. Although OLED with Mg:Ag alloy cathode has a poor rectifying property [16], it begins to leak current at about 10 V reverse bias, which can result in large crosstalk in the passive matrix displays and even cause OLED break down, this problem can be solved by connecting a diode in series to the OLED in external control circuit, which can prevent current leakage when the OLED is reversely biased.

In this paper, we used different thickness LiF buffered Mg:Ag alloy as cathode in OLED with structure of indium-tin-oxide (ITO)/N, N’-diphenyl-N, N’-(3-methylphenyl)-1,1’-biphenyl-4,4’-diamine(TPD)/tris-(8-hydroxyquinoline) aluminum(Alq3)/LiF/Mg:Ag/Ag. The devices with Mg:Ag/Ag, LiF/Al and Al-only cathodes were also fabricated in the same run for comparison.

2. Experimental details

The OLEDs were fabricated on lithographically patterned indium-tin-oxide (ITO) coated glass substrate. The ITO layer was about 60 nm thick with a sheet resistance of about 50 Ω/square. The routine cleaning procedure included ultra-sonication in acetone, ethanol, rinsing in de-ionized water and isopropyl alcohol, and finally irradiated in an oxygen plasma chamber. After the oxygen plasma treatment, the ITO substrates were transferred to the main chamber under high vacuum for devices fabrication. The main chamber is equipped with ten sources, each of which is heated by a tantalum heater. The opening and closing of shutters control the deposition sequences. The deposition rate and thickness is measured by a crystal sensor, quartz oscillator combined with frequency meter. In order to obtain large-area uniformity and abrupt interface, the chamber is equipped with three sets of shutters, i.e. besides the shutters for each crucibles, there are also a big shutter between the crucibles and substrates, and a small shutter under each substrate. The thickness/rate crystal sensor is installed in the center of the substrate holders, which is designed in a planetary rotation, and the rotation rate can be adjusted. Four samples with same/different structure can be fabricated during every run. The device has a multilayer structure of ITO/TPD (60 nm)/Alq3 (60 nm)/Cathode, where TPD is the hole-transporting layer, and Alq3 is the emissive as well as electron-transporting layer. The organic films, layer by layer, were deposited on the ITO substrate surface. After deposition of the organic layers, the top cathode was prepared by sequential deposition of a 0.5 or 1 nm LiF layer and a 200 nm Al or Mg:Ag (10:1 mass ratio) overlayer without breaking the vacuum. The four different cathode, such as Al, LiF/Al, Mg:Ag/Ag and LiF/Mg:Ag/Ag can be easy realized by opening/closing the shutter under each substrate when it is necessary. The chamber pressure was below 2×10-4 Pa during deposition of the organic materials and the metals. EL spectra of the fabricated devices were measured with a PR650 Spectra Scan spectrometer. Luminance - current density - voltage (L-I-V) characteristics were recorded simultaneously with the measurements of the EL spectra by attaching the spectrometer to a programmable Keithley 236 voltage-current source. All measurements were carried out at room temperature under ambient atmosphere.

3. Results and discussions

Current-voltage (I-V) and luminance-voltage (L-V) characteristics of the devices having LiF/Al cathode with different thickness of LiF layer and Al only cathode are shown in Figs. 1 (a) and (b), respectively. It can be seen that both I-V and L-V curves are shifted towards the lower voltage region compared with the device without LiF. At the same driving voltage, the device with a 0.5 nm LiF layer has higher current injection and luminance compared to the devices with Al only cathode or with 1 nm LiF layer. The efficiency of device with 0.5 nm LiF layer is also improved over the device with Al only cathode and the device with 1 nm LiF layer. For instance, at injection current density of 20 mA/cm2, the current efficiency and power efficiency of the devices with 0.5 nm LiF layer is as high as 4.65 cd/A and 1.63 lm/W, respectively. The Al only cathode device exhibits a lowest current efficiency and power efficiency, 0.83 cd/A and 0.19 lm/W, respectively. By increasing LiF layer to 1 nm, the current efficiency and power efficiency is decreased to 3.52 cd/A and 0.92 lm/W, respectively.

 figure: Fig. 1.

Fig. 1. Current density (a) luminance (b) versus voltage characteristics of the devices with Al cathode and different thicknesses of LiF layer.

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Figure 2 shows I-V (a) and L-V (b) characteristics of the devices having LiF/Mg:Ag/Ag cathode with different thickness of LiF layer and Mg:Ag/Ag cathode. Both I-V and L-V behaviors are in accordance with the devices with LiF/Al cathode. At the same driving voltage, the device with a 0.5 nm LiF layer has higher current injection and luminance compared to the devices with Mg:Ag/Ag cathode or with 1 nm LiF layer. The efficiency of device with 0.5 nm LiF layer is much improved over the device with Mg:Ag/Ag cathode and the device with 1 nm LiF layer. At injection current density of 20 mA/cm2, the current efficiency and power efficiency of the devices with 0.5 nm LiF layer is as high as 5.56 cd/A and 1.94 lm/W, respectively. The Mg:Ag/Ag cathode device exhibits the current efficiency and power efficiency of 3.17 cd/A and 0.95 lm/W, respectively. By increasing LiF layer to 1 nm, the current efficiency and power efficiency is also decreased to 3.58 cd/A and 1.12 lm/W, respectively. The improved efficiency of the devices with LiF buffered layer is due to higher current density injection at lower drive voltage.

 figure: Fig. 2.

Fig. 2. Current density (a) luminance (b) versus voltage characteristics of the devices with Mg:Ag/Ag cathode and different thicknesses of LiF layer.

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From the results mentioned above, it can be seen that the optimal thickness of LiF is 0.5 nm for both kinds of devices with high work function metal, Al (4.3 eV) and low work function metal, Mg:Ag (3.7 eV). Figure 3 shows I-V (a) and L-V (b) characteristics of the devices having Al, Mg:Ag/Ag cathode with or without 0.5 nm LiF buffered layer. Table 1 summarizes the EL performance of these devices. It can be seen that the device with 0.5 nm LiF buffering Mg:Ag cathode has the highest performance among the four kinds of devices. The device with 0.5 nm LiF buffering Mg:Ag/Ag cathode has the turn-on voltage as low as 2.8 V, the maximum luminance reaches 9498 cd/m2 at a voltage of 12.5 V. At injection current density of 20 mA/cm2, the current efficiency and power efficiency of the device is 5.56 cd/A and 1.94 lm/W, respectively. Compared to the device with Mg:Ag/Ag only cathode, the turn-on voltage is 1.6 V lower, the current efficiency is improved by 75 %, and power efficiency is almost double. The performance of the device is also much improved over the device with LiF/Al and Al only cathodes.

 figure: Fig. 3.

Fig. 3. Current density (a) luminance (b) versus voltage characteristics of the devices with Al, Mg:Ag/Ag cathode with or without o.5 nm LiF buffered layer.

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Tables Icon

Table 1. Electroluminescence characteristics of the OLEDs with different cathode, including the turn-on voltage (Von), maximum luminance under DC bias (Lmax), current-density (J) and voltage (V) at Lmax, current-efficiency (ηc) and power efficiency (ηP) at 20mA/cm2.

In the standard device with a configuration of ITO/TPD/Alq3/Mg:Ag, the hole injection barrier between ITO and TPD interface is only 0.2 eV, although Mg:Ag (10:1) alloy has a low work function of 3.7 eV. However, there still exists a higher electron injection barrier of 0.6 eV between Alq3 and Mg:Ag cathode. The injection of hole is much easier than electron. So the majority carrier is hole, and the minority one is electron in the device. In addition, the mobility of hole in TPD is two orders higher than that of electron in Alq3, so the hole current is much lager than electron current, the injection of electron and hole is unbalanced, resulting in low luminance efficiency of the device.

In this study, the improved performance of the devices should be due to enhanced electron injection, which can be realized by electron injection barrier reduction, i.e. reduction of cathode work function. It is known that the work function of Li (2.9 eV) is much lower than that of both Al (4.3 eV) and Mg:Ag (3.7 eV). One mechanism that can be used to explain the reduction of work function (ϕ) relates to the possible chemical reaction, Al+3LiF→AlF3+3Li+340.37 kJ/mol, Mg+2LiF→MgF2+2Li+109.62 kJ/mol and Ag+LiF→AgF+Li+412.33 kJ/mol [17], at the LiF/metal interface. The positive enthalpy of formation, 109.62 kJ/mol, 340.37 kJ/mol and 412.33 kJ/mol for LiF reaction with Mg, Al, and Ag, respectively, means the reaction is endothermic. According to Mason et al., with presence of Alq3, reaction between Al, LiF and Alq3 to liberate Li and form Alq3 anion is possible with an overall enthalpy of formation close to zero [18]. With a smaller enthalpy of formation (109.62 kJ/mol), the reaction of Mg with LiF and Alq3 is more thermodynamically favored than Al and Ag (the reaction of Ag with LiF and Alq3 should be prohibited). Thus, Mg is expected to liberate more Li. More and evenly distributed low work function Li is expected for LiF/Mg:Ag electrode. Another possible mechanism is that there is a dipole at the LiF/metal interface, which would be able to shift the work function of the metal cathode to lower energies [19]. In this case, the fact that ϕ(LiF/Mg:Ag) < ϕ (LiF/Al) should simply follow ϕ(Mg) < ϕ(Al), provided the difference of dipole values is not too much different [20].

4. Conclusion

LiF buffered low work function Mg:Ag alloy cathode can greatly improve the performance of the Alq3 based OLEDs. A 0.5 nm LiF layer can significantly enhance the electron injection, resulting in lower turn-on voltage and increased device efficiency. The enhanced electron injection is due to the reduction of metal work function, which is caused by the easier chemical reaction of Mg with LiF and possibly a dipole layer formation at the LiF/Mg:Ag interface.

Acknowledgments

The financial support from Honeywell Foundation is gratefully acknowledged.

References and links

1. L. S. Hung, C. W. Tang, and M. G. Mason, “Enhanced electron injection in organic electroluminescence devices using an Al/LiF electrode,” Appl. Phys. Lett. 70, 152–154 (1997). [CrossRef]  

2. C. H. Lee, “Enhanced efficiency and durability of organic electroluminescent devices by inserting a thin insulating layer at the Alq3/cathode interface,” Synth. Met. 91, 125–127 (1997). [CrossRef]  

3. J. Lee, Y. Park, S. K. Lee, E. -J. Cho, D. Y. Kim, H. Y. Chu, H. Lee, L. -M. Do, and T. Zyung, “Tris-(8-hydroxyquinoline)aluminum-based organic light-emitting devices with Al/CaF2 cathode: Performance enhancement and interface electronic structures,” Appl. Phys. Lett. 80, 3123–3125 (2002). [CrossRef]  

4. G. E. Jabbour, B. Kippelen, N. R. Armstrong, and N. Peyghambarian, “Aluminum based cathode structure for enhanced electron injection in electroluminescent organic devices,” Appl. Phys. Lett. 73, 1185–1187 (1998). [CrossRef]  

5. F. Li, H. Tang, J. Anderegg, and J. Shinar, “Fabrication and electroluminescence of double-layered organic light-emitting diodes with the Al2O3/Al cathode,” Appl. Phys. Lett. 70, 1233–1235 (1997). [CrossRef]  

6. S. J. Kang, D. S. Park, S. Y. Kim, C. N. Whang, K. Jeong, and S. Im, “Enhancing the electroluminescent properties of organic light-emitting devices using a thin NaCl layer” Appl. Phys. Lett. 81, 2581–2583 (2002). [CrossRef]  

7. Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003). [CrossRef]  

8. K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003). [CrossRef]  

9. S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998). [CrossRef]  

10. M. A. Baldo and S. R. Forrest, “Interface-limited injection in amorphous organic semiconductors,” Phys. Rev. B 64, 085201-1–085201-17 (2001). [CrossRef]  

11. L. S. Hung, R. Q. Zhang, P. He, and G. Mason, “Contact formation of LiF/Al cathodes in Alq-based organic light-emitting diodes,” J. Phys. D 35, 103–107 (2002). [CrossRef]  

12. T. Mori, H. Fujikawa, S. Tokito, and Y. Taga, “Electronic structure of 8-hydroxyquinoline aluminum/LiF/Al interface for organic electroluminescent device studied by ultraviolet photoelectron spectroscopy,” Appl. Phys. lett. 73, 2763–2765 (1998). [CrossRef]  

13. D. Grozea, A. Turak, X. D. Feng, Z. H. Lu, D. Johnson, and R. Wood, “Chemical structure of Al/LiF/Alq interfaces in organic light-emitting diodes,” Appl. Phys. Lett. 81, 3173–3175 (2002). [CrossRef]  

14. S. D. Wang, M. K. Fung, S. L. Lai, S. W. Tong, C. S. Lee, S. T. Lee, H. J. Zhang, and S. N. Bao, “Experimental study of a chemical reaction between LiF and Al,” J. Appl. Phys. 94, 169–173 (2003). [CrossRef]  

15. X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004). [CrossRef]  

16. Y. Kijima, N. Asai, N. Kishii, and S. Tamura, “RGB Luminescence from passive-matrix organic LED’s,” IEEE Transactions on Electron Devices , 44, 1222–1228 (1997). [CrossRef]  

17. The thermodynamic data is from NIST Chemistry WebBook, http://webbook.nist.gov.

18. M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001). [CrossRef]  

19. R. Schlaf, B. A. Parkinson, P. A. Lee, K. W. Nebesny, G. Jabbour, B. Kippelen, N. Peyghambarian, and N. R. Armstrong, “Photoemission spectroscopy of LiF coated Al and Pt electrodes,” J. Appl. Phys. 84, 6729–6736 (1998). [CrossRef]  

20. T. M. Brown, R. H. Friend, I. S. Millard, D. J. Lacey, J. H. Burroughes, and F. Cacialli, “Efficient electron injection in blue-emitting polymer light-emitting diodes with LiF/Ca/Al cathodes,” Appl. Phys. Lett. 79, 174–176 (2001). [CrossRef]  

References

  • View by:

  1. L. S. Hung, C. W. Tang, and M. G. Mason, “Enhanced electron injection in organic electroluminescence devices using an Al/LiF electrode,” Appl. Phys. Lett. 70, 152–154 (1997).
    [Crossref]
  2. C. H. Lee, “Enhanced efficiency and durability of organic electroluminescent devices by inserting a thin insulating layer at the Alq3/cathode interface,” Synth. Met. 91, 125–127 (1997).
    [Crossref]
  3. J. Lee, Y. Park, S. K. Lee, E. -J. Cho, D. Y. Kim, H. Y. Chu, H. Lee, L. -M. Do, and T. Zyung, “Tris-(8-hydroxyquinoline)aluminum-based organic light-emitting devices with Al/CaF2 cathode: Performance enhancement and interface electronic structures,” Appl. Phys. Lett. 80, 3123–3125 (2002).
    [Crossref]
  4. G. E. Jabbour, B. Kippelen, N. R. Armstrong, and N. Peyghambarian, “Aluminum based cathode structure for enhanced electron injection in electroluminescent organic devices,” Appl. Phys. Lett. 73, 1185–1187 (1998).
    [Crossref]
  5. F. Li, H. Tang, J. Anderegg, and J. Shinar, “Fabrication and electroluminescence of double-layered organic light-emitting diodes with the Al2O3/Al cathode,” Appl. Phys. Lett. 70, 1233–1235 (1997).
    [Crossref]
  6. S. J. Kang, D. S. Park, S. Y. Kim, C. N. Whang, K. Jeong, and S. Im, “Enhancing the electroluminescent properties of organic light-emitting devices using a thin NaCl layer” Appl. Phys. Lett. 81, 2581–2583 (2002).
    [Crossref]
  7. Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
    [Crossref]
  8. K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
    [Crossref]
  9. S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
    [Crossref]
  10. M. A. Baldo and S. R. Forrest, “Interface-limited injection in amorphous organic semiconductors,” Phys. Rev. B 64, 085201-1–085201-17 (2001).
    [Crossref]
  11. L. S. Hung, R. Q. Zhang, P. He, and G. Mason, “Contact formation of LiF/Al cathodes in Alq-based organic light-emitting diodes,” J. Phys. D 35, 103–107 (2002).
    [Crossref]
  12. T. Mori, H. Fujikawa, S. Tokito, and Y. Taga, “Electronic structure of 8-hydroxyquinoline aluminum/LiF/Al interface for organic electroluminescent device studied by ultraviolet photoelectron spectroscopy,” Appl. Phys. lett. 73, 2763–2765 (1998).
    [Crossref]
  13. D. Grozea, A. Turak, X. D. Feng, Z. H. Lu, D. Johnson, and R. Wood, “Chemical structure of Al/LiF/Alq interfaces in organic light-emitting diodes,” Appl. Phys. Lett. 81, 3173–3175 (2002).
    [Crossref]
  14. S. D. Wang, M. K. Fung, S. L. Lai, S. W. Tong, C. S. Lee, S. T. Lee, H. J. Zhang, and S. N. Bao, “Experimental study of a chemical reaction between LiF and Al,” J. Appl. Phys. 94, 169–173 (2003).
    [Crossref]
  15. X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
    [Crossref]
  16. Y. Kijima, N. Asai, N. Kishii, and S. Tamura, “RGB Luminescence from passive-matrix organic LED’s,” IEEE Transactions on Electron Devices,  44, 1222–1228 (1997).
    [Crossref]
  17. The thermodynamic data is from NIST Chemistry WebBook, http://webbook.nist.gov.
  18. M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
    [Crossref]
  19. R. Schlaf, B. A. Parkinson, P. A. Lee, K. W. Nebesny, G. Jabbour, B. Kippelen, N. Peyghambarian, and N. R. Armstrong, “Photoemission spectroscopy of LiF coated Al and Pt electrodes,” J. Appl. Phys. 84, 6729–6736 (1998).
    [Crossref]
  20. T. M. Brown, R. H. Friend, I. S. Millard, D. J. Lacey, J. H. Burroughes, and F. Cacialli, “Efficient electron injection in blue-emitting polymer light-emitting diodes with LiF/Ca/Al cathodes,” Appl. Phys. Lett. 79, 174–176 (2001).
    [Crossref]

2004 (1)

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

2003 (3)

S. D. Wang, M. K. Fung, S. L. Lai, S. W. Tong, C. S. Lee, S. T. Lee, H. J. Zhang, and S. N. Bao, “Experimental study of a chemical reaction between LiF and Al,” J. Appl. Phys. 94, 169–173 (2003).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

2002 (4)

S. J. Kang, D. S. Park, S. Y. Kim, C. N. Whang, K. Jeong, and S. Im, “Enhancing the electroluminescent properties of organic light-emitting devices using a thin NaCl layer” Appl. Phys. Lett. 81, 2581–2583 (2002).
[Crossref]

J. Lee, Y. Park, S. K. Lee, E. -J. Cho, D. Y. Kim, H. Y. Chu, H. Lee, L. -M. Do, and T. Zyung, “Tris-(8-hydroxyquinoline)aluminum-based organic light-emitting devices with Al/CaF2 cathode: Performance enhancement and interface electronic structures,” Appl. Phys. Lett. 80, 3123–3125 (2002).
[Crossref]

D. Grozea, A. Turak, X. D. Feng, Z. H. Lu, D. Johnson, and R. Wood, “Chemical structure of Al/LiF/Alq interfaces in organic light-emitting diodes,” Appl. Phys. Lett. 81, 3173–3175 (2002).
[Crossref]

L. S. Hung, R. Q. Zhang, P. He, and G. Mason, “Contact formation of LiF/Al cathodes in Alq-based organic light-emitting diodes,” J. Phys. D 35, 103–107 (2002).
[Crossref]

2001 (3)

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

M. A. Baldo and S. R. Forrest, “Interface-limited injection in amorphous organic semiconductors,” Phys. Rev. B 64, 085201-1–085201-17 (2001).
[Crossref]

T. M. Brown, R. H. Friend, I. S. Millard, D. J. Lacey, J. H. Burroughes, and F. Cacialli, “Efficient electron injection in blue-emitting polymer light-emitting diodes with LiF/Ca/Al cathodes,” Appl. Phys. Lett. 79, 174–176 (2001).
[Crossref]

1998 (4)

S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
[Crossref]

G. E. Jabbour, B. Kippelen, N. R. Armstrong, and N. Peyghambarian, “Aluminum based cathode structure for enhanced electron injection in electroluminescent organic devices,” Appl. Phys. Lett. 73, 1185–1187 (1998).
[Crossref]

R. Schlaf, B. A. Parkinson, P. A. Lee, K. W. Nebesny, G. Jabbour, B. Kippelen, N. Peyghambarian, and N. R. Armstrong, “Photoemission spectroscopy of LiF coated Al and Pt electrodes,” J. Appl. Phys. 84, 6729–6736 (1998).
[Crossref]

T. Mori, H. Fujikawa, S. Tokito, and Y. Taga, “Electronic structure of 8-hydroxyquinoline aluminum/LiF/Al interface for organic electroluminescent device studied by ultraviolet photoelectron spectroscopy,” Appl. Phys. lett. 73, 2763–2765 (1998).
[Crossref]

1997 (4)

Y. Kijima, N. Asai, N. Kishii, and S. Tamura, “RGB Luminescence from passive-matrix organic LED’s,” IEEE Transactions on Electron Devices,  44, 1222–1228 (1997).
[Crossref]

F. Li, H. Tang, J. Anderegg, and J. Shinar, “Fabrication and electroluminescence of double-layered organic light-emitting diodes with the Al2O3/Al cathode,” Appl. Phys. Lett. 70, 1233–1235 (1997).
[Crossref]

L. S. Hung, C. W. Tang, and M. G. Mason, “Enhanced electron injection in organic electroluminescence devices using an Al/LiF electrode,” Appl. Phys. Lett. 70, 152–154 (1997).
[Crossref]

C. H. Lee, “Enhanced efficiency and durability of organic electroluminescent devices by inserting a thin insulating layer at the Alq3/cathode interface,” Synth. Met. 91, 125–127 (1997).
[Crossref]

Anderegg, J.

F. Li, H. Tang, J. Anderegg, and J. Shinar, “Fabrication and electroluminescence of double-layered organic light-emitting diodes with the Al2O3/Al cathode,” Appl. Phys. Lett. 70, 1233–1235 (1997).
[Crossref]

Armstrong, N. R.

G. E. Jabbour, B. Kippelen, N. R. Armstrong, and N. Peyghambarian, “Aluminum based cathode structure for enhanced electron injection in electroluminescent organic devices,” Appl. Phys. Lett. 73, 1185–1187 (1998).
[Crossref]

S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
[Crossref]

R. Schlaf, B. A. Parkinson, P. A. Lee, K. W. Nebesny, G. Jabbour, B. Kippelen, N. Peyghambarian, and N. R. Armstrong, “Photoemission spectroscopy of LiF coated Al and Pt electrodes,” J. Appl. Phys. 84, 6729–6736 (1998).
[Crossref]

Asai, N.

Y. Kijima, N. Asai, N. Kishii, and S. Tamura, “RGB Luminescence from passive-matrix organic LED’s,” IEEE Transactions on Electron Devices,  44, 1222–1228 (1997).
[Crossref]

Baldo, M. A.

M. A. Baldo and S. R. Forrest, “Interface-limited injection in amorphous organic semiconductors,” Phys. Rev. B 64, 085201-1–085201-17 (2001).
[Crossref]

Bao, S. N.

S. D. Wang, M. K. Fung, S. L. Lai, S. W. Tong, C. S. Lee, S. T. Lee, H. J. Zhang, and S. N. Bao, “Experimental study of a chemical reaction between LiF and Al,” J. Appl. Phys. 94, 169–173 (2003).
[Crossref]

Bredas, J. L.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Brown, T. M.

T. M. Brown, R. H. Friend, I. S. Millard, D. J. Lacey, J. H. Burroughes, and F. Cacialli, “Efficient electron injection in blue-emitting polymer light-emitting diodes with LiF/Ca/Al cathodes,” Appl. Phys. Lett. 79, 174–176 (2001).
[Crossref]

Burroughes, J. H.

T. M. Brown, R. H. Friend, I. S. Millard, D. J. Lacey, J. H. Burroughes, and F. Cacialli, “Efficient electron injection in blue-emitting polymer light-emitting diodes with LiF/Ca/Al cathodes,” Appl. Phys. Lett. 79, 174–176 (2001).
[Crossref]

Cacialli, F.

T. M. Brown, R. H. Friend, I. S. Millard, D. J. Lacey, J. H. Burroughes, and F. Cacialli, “Efficient electron injection in blue-emitting polymer light-emitting diodes with LiF/Ca/Al cathodes,” Appl. Phys. Lett. 79, 174–176 (2001).
[Crossref]

Cheng, L. F.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Cho, E. -J.

J. Lee, Y. Park, S. K. Lee, E. -J. Cho, D. Y. Kim, H. Y. Chu, H. Lee, L. -M. Do, and T. Zyung, “Tris-(8-hydroxyquinoline)aluminum-based organic light-emitting devices with Al/CaF2 cathode: Performance enhancement and interface electronic structures,” Appl. Phys. Lett. 80, 3123–3125 (2002).
[Crossref]

Chu, H. Y.

J. Lee, Y. Park, S. K. Lee, E. -J. Cho, D. Y. Kim, H. Y. Chu, H. Lee, L. -M. Do, and T. Zyung, “Tris-(8-hydroxyquinoline)aluminum-based organic light-emitting devices with Al/CaF2 cathode: Performance enhancement and interface electronic structures,” Appl. Phys. Lett. 80, 3123–3125 (2002).
[Crossref]

Ding, H. J.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Ding, X. M.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Do, L. -M.

J. Lee, Y. Park, S. K. Lee, E. -J. Cho, D. Y. Kim, H. Y. Chu, H. Lee, L. -M. Do, and T. Zyung, “Tris-(8-hydroxyquinoline)aluminum-based organic light-emitting devices with Al/CaF2 cathode: Performance enhancement and interface electronic structures,” Appl. Phys. Lett. 80, 3123–3125 (2002).
[Crossref]

dos Santos, D. A.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Feng, X. D.

D. Grozea, A. Turak, X. D. Feng, Z. H. Lu, D. Johnson, and R. Wood, “Chemical structure of Al/LiF/Alq interfaces in organic light-emitting diodes,” Appl. Phys. Lett. 81, 3173–3175 (2002).
[Crossref]

Forrest, S. R.

M. A. Baldo and S. R. Forrest, “Interface-limited injection in amorphous organic semiconductors,” Phys. Rev. B 64, 085201-1–085201-17 (2001).
[Crossref]

Friend, R. H.

T. M. Brown, R. H. Friend, I. S. Millard, D. J. Lacey, J. H. Burroughes, and F. Cacialli, “Efficient electron injection in blue-emitting polymer light-emitting diodes with LiF/Ca/Al cathodes,” Appl. Phys. Lett. 79, 174–176 (2001).
[Crossref]

Fujikawa, H.

T. Mori, H. Fujikawa, S. Tokito, and Y. Taga, “Electronic structure of 8-hydroxyquinoline aluminum/LiF/Al interface for organic electroluminescent device studied by ultraviolet photoelectron spectroscopy,” Appl. Phys. lett. 73, 2763–2765 (1998).
[Crossref]

Fung, M. K.

S. D. Wang, M. K. Fung, S. L. Lai, S. W. Tong, C. S. Lee, S. T. Lee, H. J. Zhang, and S. N. Bao, “Experimental study of a chemical reaction between LiF and Al,” J. Appl. Phys. 94, 169–173 (2003).
[Crossref]

Gao, Y.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Giesen, D. J.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Grozea, D.

D. Grozea, A. Turak, X. D. Feng, Z. H. Lu, D. Johnson, and R. Wood, “Chemical structure of Al/LiF/Alq interfaces in organic light-emitting diodes,” Appl. Phys. Lett. 81, 3173–3175 (2002).
[Crossref]

He, J.

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

He, P.

L. S. Hung, R. Q. Zhang, P. He, and G. Mason, “Contact formation of LiF/Al cathodes in Alq-based organic light-emitting diodes,” J. Phys. D 35, 103–107 (2002).
[Crossref]

Hou, X. Y.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Huang, W.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Hung, L. S.

L. S. Hung, R. Q. Zhang, P. He, and G. Mason, “Contact formation of LiF/Al cathodes in Alq-based organic light-emitting diodes,” J. Phys. D 35, 103–107 (2002).
[Crossref]

L. S. Hung, C. W. Tang, and M. G. Mason, “Enhanced electron injection in organic electroluminescence devices using an Al/LiF electrode,” Appl. Phys. Lett. 70, 152–154 (1997).
[Crossref]

Hung, L.-S.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Hwang, C. C.

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

Ihm, K.

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

Im, S.

S. J. Kang, D. S. Park, S. Y. Kim, C. N. Whang, K. Jeong, and S. Im, “Enhancing the electroluminescent properties of organic light-emitting devices using a thin NaCl layer” Appl. Phys. Lett. 81, 2581–2583 (2002).
[Crossref]

Jabbour, G.

R. Schlaf, B. A. Parkinson, P. A. Lee, K. W. Nebesny, G. Jabbour, B. Kippelen, N. Peyghambarian, and N. R. Armstrong, “Photoemission spectroscopy of LiF coated Al and Pt electrodes,” J. Appl. Phys. 84, 6729–6736 (1998).
[Crossref]

Jabbour, G. E.

G. E. Jabbour, B. Kippelen, N. R. Armstrong, and N. Peyghambarian, “Aluminum based cathode structure for enhanced electron injection in electroluminescent organic devices,” Appl. Phys. Lett. 73, 1185–1187 (1998).
[Crossref]

S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
[Crossref]

Jeon, C. H.

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

Jeong, K.

S. J. Kang, D. S. Park, S. Y. Kim, C. N. Whang, K. Jeong, and S. Im, “Enhancing the electroluminescent properties of organic light-emitting devices using a thin NaCl layer” Appl. Phys. Lett. 81, 2581–2583 (2002).
[Crossref]

Johnson, D.

D. Grozea, A. Turak, X. D. Feng, Z. H. Lu, D. Johnson, and R. Wood, “Chemical structure of Al/LiF/Alq interfaces in organic light-emitting diodes,” Appl. Phys. Lett. 81, 3173–3175 (2002).
[Crossref]

Kang, S. J.

S. J. Kang, D. S. Park, S. Y. Kim, C. N. Whang, K. Jeong, and S. Im, “Enhancing the electroluminescent properties of organic light-emitting devices using a thin NaCl layer” Appl. Phys. Lett. 81, 2581–2583 (2002).
[Crossref]

Kang, T. H.

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

Kawabe, Y.

S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
[Crossref]

Kijima, Y.

Y. Kijima, N. Asai, N. Kishii, and S. Tamura, “RGB Luminescence from passive-matrix organic LED’s,” IEEE Transactions on Electron Devices,  44, 1222–1228 (1997).
[Crossref]

Kim, B.

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

Kim, D. Y.

J. Lee, Y. Park, S. K. Lee, E. -J. Cho, D. Y. Kim, H. Y. Chu, H. Lee, L. -M. Do, and T. Zyung, “Tris-(8-hydroxyquinoline)aluminum-based organic light-emitting devices with Al/CaF2 cathode: Performance enhancement and interface electronic structures,” Appl. Phys. Lett. 80, 3123–3125 (2002).
[Crossref]

Kim, K.

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

Kim, K. J.

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

Kim, S. Y.

S. J. Kang, D. S. Park, S. Y. Kim, C. N. Whang, K. Jeong, and S. Im, “Enhancing the electroluminescent properties of organic light-emitting devices using a thin NaCl layer” Appl. Phys. Lett. 81, 2581–2583 (2002).
[Crossref]

Kippelen, B.

G. E. Jabbour, B. Kippelen, N. R. Armstrong, and N. Peyghambarian, “Aluminum based cathode structure for enhanced electron injection in electroluminescent organic devices,” Appl. Phys. Lett. 73, 1185–1187 (1998).
[Crossref]

S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
[Crossref]

R. Schlaf, B. A. Parkinson, P. A. Lee, K. W. Nebesny, G. Jabbour, B. Kippelen, N. Peyghambarian, and N. R. Armstrong, “Photoemission spectroscopy of LiF coated Al and Pt electrodes,” J. Appl. Phys. 84, 6729–6736 (1998).
[Crossref]

Kishii, N.

Y. Kijima, N. Asai, N. Kishii, and S. Tamura, “RGB Luminescence from passive-matrix organic LED’s,” IEEE Transactions on Electron Devices,  44, 1222–1228 (1997).
[Crossref]

Lacey, D. J.

T. M. Brown, R. H. Friend, I. S. Millard, D. J. Lacey, J. H. Burroughes, and F. Cacialli, “Efficient electron injection in blue-emitting polymer light-emitting diodes with LiF/Ca/Al cathodes,” Appl. Phys. Lett. 79, 174–176 (2001).
[Crossref]

Lai, S. L.

S. D. Wang, M. K. Fung, S. L. Lai, S. W. Tong, C. S. Lee, S. T. Lee, H. J. Zhang, and S. N. Bao, “Experimental study of a chemical reaction between LiF and Al,” J. Appl. Phys. 94, 169–173 (2003).
[Crossref]

Le, Q. T.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Lee, C. H.

C. H. Lee, “Enhanced efficiency and durability of organic electroluminescent devices by inserting a thin insulating layer at the Alq3/cathode interface,” Synth. Met. 91, 125–127 (1997).
[Crossref]

Lee, C. S.

S. D. Wang, M. K. Fung, S. L. Lai, S. W. Tong, C. S. Lee, S. T. Lee, H. J. Zhang, and S. N. Bao, “Experimental study of a chemical reaction between LiF and Al,” J. Appl. Phys. 94, 169–173 (2003).
[Crossref]

Lee, H.

J. Lee, Y. Park, S. K. Lee, E. -J. Cho, D. Y. Kim, H. Y. Chu, H. Lee, L. -M. Do, and T. Zyung, “Tris-(8-hydroxyquinoline)aluminum-based organic light-emitting devices with Al/CaF2 cathode: Performance enhancement and interface electronic structures,” Appl. Phys. Lett. 80, 3123–3125 (2002).
[Crossref]

Lee, J.

J. Lee, Y. Park, S. K. Lee, E. -J. Cho, D. Y. Kim, H. Y. Chu, H. Lee, L. -M. Do, and T. Zyung, “Tris-(8-hydroxyquinoline)aluminum-based organic light-emitting devices with Al/CaF2 cathode: Performance enhancement and interface electronic structures,” Appl. Phys. Lett. 80, 3123–3125 (2002).
[Crossref]

Lee, K. B.

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

Lee, P. A.

R. Schlaf, B. A. Parkinson, P. A. Lee, K. W. Nebesny, G. Jabbour, B. Kippelen, N. Peyghambarian, and N. R. Armstrong, “Photoemission spectroscopy of LiF coated Al and Pt electrodes,” J. Appl. Phys. 84, 6729–6736 (1998).
[Crossref]

Lee, S. K.

J. Lee, Y. Park, S. K. Lee, E. -J. Cho, D. Y. Kim, H. Y. Chu, H. Lee, L. -M. Do, and T. Zyung, “Tris-(8-hydroxyquinoline)aluminum-based organic light-emitting devices with Al/CaF2 cathode: Performance enhancement and interface electronic structures,” Appl. Phys. Lett. 80, 3123–3125 (2002).
[Crossref]

Lee, S. T.

S. D. Wang, M. K. Fung, S. L. Lai, S. W. Tong, C. S. Lee, S. T. Lee, H. J. Zhang, and S. N. Bao, “Experimental study of a chemical reaction between LiF and Al,” J. Appl. Phys. 94, 169–173 (2003).
[Crossref]

Lee, S.-T.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Li, F.

F. Li, H. Tang, J. Anderegg, and J. Shinar, “Fabrication and electroluminescence of double-layered organic light-emitting diodes with the Al2O3/Al cathode,” Appl. Phys. Lett. 70, 1233–1235 (1997).
[Crossref]

Liao, L. S.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Liu, Y.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Lu, Z. H.

D. Grozea, A. Turak, X. D. Feng, Z. H. Lu, D. Johnson, and R. Wood, “Chemical structure of Al/LiF/Alq interfaces in organic light-emitting diodes,” Appl. Phys. Lett. 81, 3173–3175 (2002).
[Crossref]

Madathil, J.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Mash, E. A.

S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
[Crossref]

Mason, G.

L. S. Hung, R. Q. Zhang, P. He, and G. Mason, “Contact formation of LiF/Al cathodes in Alq-based organic light-emitting diodes,” J. Phys. D 35, 103–107 (2002).
[Crossref]

Mason, M. G.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

L. S. Hung, C. W. Tang, and M. G. Mason, “Enhanced electron injection in organic electroluminescence devices using an Al/LiF electrode,” Appl. Phys. Lett. 70, 152–154 (1997).
[Crossref]

Millard, I. S.

T. M. Brown, R. H. Friend, I. S. Millard, D. J. Lacey, J. H. Burroughes, and F. Cacialli, “Efficient electron injection in blue-emitting polymer light-emitting diodes with LiF/Ca/Al cathodes,” Appl. Phys. Lett. 79, 174–176 (2001).
[Crossref]

Mori, T.

T. Mori, H. Fujikawa, S. Tokito, and Y. Taga, “Electronic structure of 8-hydroxyquinoline aluminum/LiF/Al interface for organic electroluminescent device studied by ultraviolet photoelectron spectroscopy,” Appl. Phys. lett. 73, 2763–2765 (1998).
[Crossref]

Morrell, M. M.

S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
[Crossref]

Nabor, M. -F.

S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
[Crossref]

Nebesny, K. W.

R. Schlaf, B. A. Parkinson, P. A. Lee, K. W. Nebesny, G. Jabbour, B. Kippelen, N. Peyghambarian, and N. R. Armstrong, “Photoemission spectroscopy of LiF coated Al and Pt electrodes,” J. Appl. Phys. 84, 6729–6736 (1998).
[Crossref]

Obbard, E.

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Obbard, E. G.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Park, C. Y.

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

Park, D. S.

S. J. Kang, D. S. Park, S. Y. Kim, C. N. Whang, K. Jeong, and S. Im, “Enhancing the electroluminescent properties of organic light-emitting devices using a thin NaCl layer” Appl. Phys. Lett. 81, 2581–2583 (2002).
[Crossref]

Park, Y.

J. Lee, Y. Park, S. K. Lee, E. -J. Cho, D. Y. Kim, H. Y. Chu, H. Lee, L. -M. Do, and T. Zyung, “Tris-(8-hydroxyquinoline)aluminum-based organic light-emitting devices with Al/CaF2 cathode: Performance enhancement and interface electronic structures,” Appl. Phys. Lett. 80, 3123–3125 (2002).
[Crossref]

Park, Y. J.

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

Parkinson, B. A.

R. Schlaf, B. A. Parkinson, P. A. Lee, K. W. Nebesny, G. Jabbour, B. Kippelen, N. Peyghambarian, and N. R. Armstrong, “Photoemission spectroscopy of LiF coated Al and Pt electrodes,” J. Appl. Phys. 84, 6729–6736 (1998).
[Crossref]

Peyghambarian, N.

R. Schlaf, B. A. Parkinson, P. A. Lee, K. W. Nebesny, G. Jabbour, B. Kippelen, N. Peyghambarian, and N. R. Armstrong, “Photoemission spectroscopy of LiF coated Al and Pt electrodes,” J. Appl. Phys. 84, 6729–6736 (1998).
[Crossref]

S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
[Crossref]

G. E. Jabbour, B. Kippelen, N. R. Armstrong, and N. Peyghambarian, “Aluminum based cathode structure for enhanced electron injection in electroluminescent organic devices,” Appl. Phys. Lett. 73, 1185–1187 (1998).
[Crossref]

Raychaudhuri, P.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Salaneck, W. R.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Schlaf, R.

R. Schlaf, B. A. Parkinson, P. A. Lee, K. W. Nebesny, G. Jabbour, B. Kippelen, N. Peyghambarian, and N. R. Armstrong, “Photoemission spectroscopy of LiF coated Al and Pt electrodes,” J. Appl. Phys. 84, 6729–6736 (1998).
[Crossref]

S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
[Crossref]

Shaheen, S. E.

S. E. Shaheen, G. E. Jabbour, M. M. Morrell, Y. Kawabe, B. Kippelen, N. Peyghambarian, M. -F. Nabor, R. Schlaf, E. A. Mash, and N. R. Armstrong, “Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode,” J. Appl. Phys. 84, 2324–2327 (1998).
[Crossref]

Shi, H. Z.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Shinar, J.

F. Li, H. Tang, J. Anderegg, and J. Shinar, “Fabrication and electroluminescence of double-layered organic light-emitting diodes with the Al2O3/Al cathode,” Appl. Phys. Lett. 70, 1233–1235 (1997).
[Crossref]

Taga, Y.

T. Mori, H. Fujikawa, S. Tokito, and Y. Taga, “Electronic structure of 8-hydroxyquinoline aluminum/LiF/Al interface for organic electroluminescent device studied by ultraviolet photoelectron spectroscopy,” Appl. Phys. lett. 73, 2763–2765 (1998).
[Crossref]

Tak, Y. H.

K. Ihm, T. H. Kang, K. J. Kim, C. C. Hwang, Y. J. Park, K. B. Lee, B. Kim, C. H. Jeon, C. Y. Park, K. Kim, and Y. H. Tak, “Band bending of LiF/Alq3 interface in organic light-emitting diodes” Appl. Phys. Lett. 83, 2949–2951 (2003).
[Crossref]

Tamura, S.

Y. Kijima, N. Asai, N. Kishii, and S. Tamura, “RGB Luminescence from passive-matrix organic LED’s,” IEEE Transactions on Electron Devices,  44, 1222–1228 (1997).
[Crossref]

Tang, C. W.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

L. S. Hung, C. W. Tang, and M. G. Mason, “Enhanced electron injection in organic electroluminescence devices using an Al/LiF electrode,” Appl. Phys. Lett. 70, 152–154 (1997).
[Crossref]

Tang, H.

F. Li, H. Tang, J. Anderegg, and J. Shinar, “Fabrication and electroluminescence of double-layered organic light-emitting diodes with the Al2O3/Al cathode,” Appl. Phys. Lett. 70, 1233–1235 (1997).
[Crossref]

Tokito, S.

T. Mori, H. Fujikawa, S. Tokito, and Y. Taga, “Electronic structure of 8-hydroxyquinoline aluminum/LiF/Al interface for organic electroluminescent device studied by ultraviolet photoelectron spectroscopy,” Appl. Phys. lett. 73, 2763–2765 (1998).
[Crossref]

Tong, S. W.

S. D. Wang, M. K. Fung, S. L. Lai, S. W. Tong, C. S. Lee, S. T. Lee, H. J. Zhang, and S. N. Bao, “Experimental study of a chemical reaction between LiF and Al,” J. Appl. Phys. 94, 169–173 (2003).
[Crossref]

Turak, A.

D. Grozea, A. Turak, X. D. Feng, Z. H. Lu, D. Johnson, and R. Wood, “Chemical structure of Al/LiF/Alq interfaces in organic light-emitting diodes,” Appl. Phys. Lett. 81, 3173–3175 (2002).
[Crossref]

Wang, S. D.

S. D. Wang, M. K. Fung, S. L. Lai, S. W. Tong, C. S. Lee, S. T. Lee, H. J. Zhang, and S. N. Bao, “Experimental study of a chemical reaction between LiF and Al,” J. Appl. Phys. 94, 169–173 (2003).
[Crossref]

Wang, X. J.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Wang, X. Z.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Wang, Z. J.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Whang, C. N.

S. J. Kang, D. S. Park, S. Y. Kim, C. N. Whang, K. Jeong, and S. Im, “Enhancing the electroluminescent properties of organic light-emitting devices using a thin NaCl layer” Appl. Phys. Lett. 81, 2581–2583 (2002).
[Crossref]

Wood, R.

D. Grozea, A. Turak, X. D. Feng, Z. H. Lu, D. Johnson, and R. Wood, “Chemical structure of Al/LiF/Alq interfaces in organic light-emitting diodes,” Appl. Phys. Lett. 81, 3173–3175 (2002).
[Crossref]

Xiong, Z. H.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Xu, Z.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Yan, L.

M. G. Mason, C. W. Tang, L.-S. Hung, P. Raychaudhuri, J. Madathil, D. J. Giesen, L. Yan, Q. T. Le, Y. Gao, S.-T. Lee, L. S. Liao, L. F. Cheng, W. R. Salaneck, D. A. dos Santos, and J. L. Bredas, “Interficial chemistry of Alq3 and LiF with reactive metals”, J. Appl. Phys. 89, 2756–2765 (2001).
[Crossref]

Zhan, Y. Q.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Zhang, H. J.

S. D. Wang, M. K. Fung, S. L. Lai, S. W. Tong, C. S. Lee, S. T. Lee, H. J. Zhang, and S. N. Bao, “Experimental study of a chemical reaction between LiF and Al,” J. Appl. Phys. 94, 169–173 (2003).
[Crossref]

Zhang, R. Q.

L. S. Hung, R. Q. Zhang, P. He, and G. Mason, “Contact formation of LiF/Al cathodes in Alq-based organic light-emitting diodes,” J. Phys. D 35, 103–107 (2002).
[Crossref]

Zhang, S. T.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Zhao, J. M.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Zhong, G. Y.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Y. Q. Zhan, Z. H. Xiong, H. Z. Shi, S. T. Zhang, Z. Xu, G. Y. Zhong, J. He, J. M. Zhao, Z. J. Wang, E. Obbard, H. J. Ding, X. J. Wang, X. M. Ding, W. Huang, and X. Y. Hou, “Sodium stearate, an effective amphiphilic molecule buffer material between organic and metal layers in organic light-emitting devices,” Appl. Phys. Lett. 83, 1656–1658 (2003).
[Crossref]

Zhou, Y. C.

X. J. Wang, J. M. Zhao, Y. C. Zhou, X. Z. Wang, S. T. Zhang, Y. Q. Zhan, Z. Xu, H. J. Ding, G. Y. Zhong, H. Z. Shi, Z. H. Xiong, Y. Liu, Z. J. Wang, E. G. Obbard, X. M. Ding, W. Huang, and X. Y. Hou, “Enhancement of electron injection in organic light-emitting devices using an Ag/LiF cathode,” J. Appl. Phys. 95, 3828–3830 (2004).
[Crossref]

Zyung, T.

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Other (1)

The thermodynamic data is from NIST Chemistry WebBook, http://webbook.nist.gov.

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Figures (3)

Fig. 1.
Fig. 1. Current density (a) luminance (b) versus voltage characteristics of the devices with Al cathode and different thicknesses of LiF layer.
Fig. 2.
Fig. 2. Current density (a) luminance (b) versus voltage characteristics of the devices with Mg:Ag/Ag cathode and different thicknesses of LiF layer.
Fig. 3.
Fig. 3. Current density (a) luminance (b) versus voltage characteristics of the devices with Al, Mg:Ag/Ag cathode with or without o.5 nm LiF buffered layer.

Tables (1)

Tables Icon

Table 1. Electroluminescence characteristics of the OLEDs with different cathode, including the turn-on voltage (Von), maximum luminance under DC bias (Lmax), current-density (J) and voltage (V) at Lmax, current-efficiency (ηc) and power efficiency (ηP) at 20mA/cm2.

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