Abstract

It is believed that mechanical stress of ~10^a dyn/cm² adversely affects the reliability and lifetime of diode lasers.¹ However, an accurate and practical method of measuring stress in diode lasers is required to determine the role of stress in device degradation and optimize manufacturing processes to reduce stress. We have measured stresses on the facets of GaAs-based diode lasers using spatially resolved and polarization-resolved photo luminescence. The spatial resolution of ~1 μm and the stress resolution of ~10⁷ dyn/cm² (strain resolution ~10^-5) of this technique make it suitable for measuring the important stress distributions near the active region of diode lasers. Polarization-resolved photoluminescence is more accurate and cost-effective than alternative methods such as x-ray diffraction² or Raman spectroscopy.³

© 1992 Optical Society of America