Schottky barrier characteristics of Pt contacts to n-type InGaN

Abstract

Schottky barrier behaviors of Pt contacts to n-InGaN have been investigated by means of current-voltage (I-V) and capacitance-voltage (C-V) methods. It is found that the Schottky barrier heights (SBHs) determined by thermionic emission (TE) and thermionic field emission (TFE) modes using the I-V data are quite different from each other. However, the SBHs obtained by the TFE mode are fairly similar to theoretically calculated values, which are in good agreement with the results obtained by the C-V method. It is also shown that the SBHs and the ideality factors calculated by the TE and TFE modes decrease with increasing annealing temperature. The different SBHs obtained by the TE and TFE modes, the annealing temperature dependence of the SBHs, and the ideality factors are described and discussed in terms of the presence of different types of native point defects near the InGaN surface.