PHOTOELECTRIC PROPERTIES OF GASB SCHOTTKY DIODES

Electrical and photoelectrical properties of GaSb Schottky diodes obta ined by evaporating gold metal dots on sulphur treated or chemically e tched surfaces of Te-doped n-GaSb crystals (grown from melt by Czochra lski method), with Hall carrier density in the range of 1.8-6.5x10(17) cm(-3), were: studied. J/V characteristics with an ideality factor ra nging between 1.17 and 1.22 were measured on Schottky diodes prepared on sulphur passivated surfaces. After image force effect correction, p hotoelectric determination of the barrier height (q Phi(b)=0.598+/-0.0 06 eV) has been found to be independent of the surface treatment and, in the case of the sulphur-treated diodes, in good agreement with the value obtained through C-2 vs reverse bias measurements (q Phi(b)=0.6/-0.01 eV). Through spectral response analysis of Schottky diodes, an estimation of minority carrier diffusion length value is given. A majo r role of sulphur passivation on preparation of Schottky barrier with good and well reproducible electrical properties is confirmed. (C) 199 7 American Institute of Physics.