Analysis of I-V measurements on Pt/Au-GaN Schottky contacts in a wide temperature range

The formerly derived modified method of evaluation of the Schottky barrier height applied on Pt/Au-GaN Schottky structures is presented. It is based on the measurement of I-V characteristics in a wide temperature range. By subtraction of generation-recombination, tunnelling and leakage currents from the total current, the "pure" thermionic emission current I_te and subsequently Schottky barrier height φ_b can be evaluated with higher physical relevance. The advantage of the mentioned method is that it allows evaluation of φ_b from the measured I-V characteristics which significantly deviate from the ideal thermionic-emission characteristics represented in semi-logarithmic coordinates by a straight line. The determination of the Schottky barrier ob on GaN and related compound semiconductors with higher precision is important for further analysis of new combinations of metals and semiconductors and better understanding of the physical behaviour at the interface.