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Photovoltages (surface photovoltage plus Dember voltage) were calculated, taking into consideration the influence of charge exchange between a continuum of surface states and the semiconductor, the barrier lowering as a result of the Schottky effect, the applied voltage drop and transmission coefficient across the interfacial layer. For moderate band bending, the photovoltage depends on several parameters which renders their reliable determination very difficult. For extreme band bending, however, only doping factor, mobility ratio and relative excess concentration enter into given formulas. The obtained analytical expression includes saturation effects at the surface, so that the photovoltage (SPV) does not exceed the thermodynamic band bending. The bulk effect of the Dember voltage is then added to obtain the relationship between the light generated current and open circuit voltage at the terminals. Results were applied to Schottky barrier diodes Au/InP(n). The InP substrate is restructured by some monolayers of InSb thin film [L. Bideux, B. Gruzza, A. Porte, H. Robert, Surface and Interface Analysis 20 (1993) 803]. Good agreement between parameters determined in this way and otherwise indicates the validity of the model and the approximations used in this work.

In this work, we measure the current–voltage ( I – V ) and the capacitance–voltage ( C – V ) characteristics of the Au/InP(100) and Au/InSb/InP(100) Schottky type diodes. The InP( n ) substrate is restructured by some monolayers of the InSb thin film. We then propose a study of the electrical quality of the elaborated components after the Au/InP interface creation; first without annealing and then after annealing by heating at 500°C temperatures. Analysis of the measured I ( V ) characteristics for the Au/InP and Au/InSb/InP samples allows the determination of the electrical parameter variations. The saturation current I s , the serial resistance R s , the mean ideality factor n and also the barrier height φ B n , are respectively equal to 2.10×10 −4 A, 19 Ω, 1.8 and 0.401 eV for the Au/InP sample and equal to 1.34×10 −7 A, 175 Ω, 1.78 and 0.592 eV for the Au/heated InSb/InP. Another good result is that the analysis and simulation of the I ( V ) and the C ( V ) characteristics allows us to determine the very important mean interfacial state density N ss(mean) , and is obtained to be equal 4.23×10 12 eV −1 cm −2 for the Au/InP sample and equal to 4.42×10 12 eV −1 cm −2 for the Au/heated InSb/InP. This work thus permits the evolution study of these electrical parameters related to the restructuration conditions.