High temperature characterization of Pt‐based Schottky diodes on AlGaN/GaN heterostructures

Abstract

Abstract The performance of Pt/(Ti)/Au Schottky contacts on AlGaN/GaN heterostructures up to 360 °C has been investigated by means of I‐V‐T measurements. A simultaneous increase of the effective barrier height and a decrease of the ideality factor with increasing temperature is observed. Barrier values of 1.05‐1.15 eV and a n‐values of 1.35‐1.55 are obtained above 300 °C. A reversible behaviour during the cooling is observed for the Pt/Ti/Au contacts, whereas a slight degradation is observed in the Pt/Au case. The insertion of an intermediate Ti layer is revealed to highly improve the thermal stability of the devices. The diode parameters are significantly enhanced throughout the whole thermal cycle when this intermediate layer is 10 nm thick. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)