Abstract

The field-dependence of the resistivity of boron-doped homoepitaxial, small-grain and large-grain diamond films deposited on insulating substrates is investigated as a function of grain size and temperature. The resistivity of the epitaxial film remained independent of field for the temperature and field ranges of 296 - 633K and 40 - 600 V/cm, respectively. The small grain films exhibited a change of resistivity starting at 10 V/cm for the 21Ω-cm sample but showed no change for the 4.9Ω-cm sample. The resistivity of the film with a grain size of 200-300μm starts decreasing at approximately 0.2V/cm at room temperature. The rate of resistivity reduction due to field increases in the temperature range of 296 - 510K, then starts to decrease between 510 - 633K.

© 1995 Optical Society of America