Semiconductor surface study by transverse acoustoelectric voltage using surface acoustic waves

• Published in: Solid-state electronics Vol. 19; no. 2; pp. 121 - 123
• Main Authors: Das, P., Motamedi, M.E., Webster, R.T.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.1976
• ISSN: 0038-1101; 1879-2405
• DOI: 10.1016/0038-1101(76)90088-5

Electrical properties of semiconductor surfaces can be determined by measuring the transverse acoustoelectric voltage. This voltage is produced by the interaction of the surface acoustic wave propagating on a piezoelectric substrate and the carriers on semiconductor surface placed in proximity. Using 110 MHz LiNbO 3 delay lines, the transverse acoustoelectric voltage has been measured across CdS and Si, the surface properties of which are varied by different light illumination. Detailed study of the voltage waveform reveals the type of traps and the amount of charge in the traps. The method is simple, needs no contacts to the sample, and is sensitive.