Analysis and simulation of Au/InSb/InP diode C-V characteristic:: modeling and experiments

The effects of the energy density distribution and relaxation time of the interface state on electric parameters of Au/InSb/InP(100) Schottky diodes were investigated, in the latter diode, InSb forms a fine restructuration layer allowing to block P atoms migration to surface. To be sure of the disappearance of the In droplets, a high quantity of Sb was evaporated and the excess was eliminated by heating the substrate surface at 300 degreesC before evaporating An onto it. The current-voltage I(V-G) and capacitance-voltage C(V-G) characteristics are measured as a function of frequency (100 Hz-1 MHz). Typical Ln[I/(1 - e(-qVG/kT))] versus V-G characteristics of Au/heated InSb/InP(100) Schottky diode under forward bias show two linear regions separated by a transition segment. From the first region, the slope and the intercept of this plot on the current axis allow to determine the ideality factor n and the saturation current I-s evaluated to 1.79 and 1.64 x 10(-7) A, respectively. The mean density of interface states estimated from the C(V-G) measurements was 1.57 10(12) cm(-2) eV(-1). The interface states were responsible for the non-ideal behavior of the I(V-G) characteristics, the capture cross-section sigma(n) for the fast slow varies between 2.16 x 10(-11) and 7.13 x 10(-12) cm(2) for the relaxation times range 7.9 x 10(-3)-2.4 x 10(-2)s. (C) 2002 Elsevier Science B.V. All rights reserved.