Hole Schottky barrier height enhancement and its application to metal-semiconductor-metal photodetectors

Hole Schottky barrier heights on GaAs have been studied experimentally by u sing a conventional metal-semiconductor-metal photodetector (MSMPD) structu re. The Schottky barrier height for holes was obtained directly by the hole -current dominated dark current measurement of the MSMPD. With a thin, high ly doped surface layer, control of the Schottky barrier heights for holes f rom 0.48 to 0.79 eV was obtained. By using these engineered Schottky contac ts in the MSMPDs, over three orders of magnitude reduction in the dark curr ents of the MSMPDs was achieved. (C) 2001 American Institute of Physics.