Thermal and chemical stability of Schottky metallization on GaAs

Abstract

The high-temperature stability of Schottky barriers on GaAs has been correlated with the thermodynamic driving force for chemical reaction between the metallic contacts and the substrate. The chemical stability of a gate metallurgy can result in the stability of the electrical characteristics of the contact after high-temperature anneal. Since single element metal contacts on GaAs are chemically unstable, thermally stable Schottky barriers are not expected from these systems. Alternatively, most of the common metal silicides are chemically stable on GaAs and hence are more likely to form Schottky barriers which are stable against high-temperature annealing. The chemically stable silicides of Ni and Co, which exhibit low electrical resistivities, are suggested as improved gate metallurgies in self-aligned metal-semiconductor field-effect transistor technologies.

The Effect of High Temperature Annealing on Schottky Diode Characteristics of CoCr/n-LEC GaAs Contacts

“…It has been reported in the study on Co/n-GaAs Schottky diodes by Everaert et al [7] that contacts remained stable up to 300 C and deterioration started at temperatures above 300 C. As it can be seen from Fig. 2, the thermal stability of the CoCr alloy/n-GaAs contact maintained up to about 700 C. Lau et al [17] reported that the stability of electrical characteristics of a contact after high-temperature annealing was directly correlated to the chemical stability of the metallurgy.…”

Electrical Properties of Thermally Annealed β-Ga2O3 Metal-Semiconductor Field-Effect Transistors with Pt/Au Schottky Contacts

“…27,28 This may have caused the Schottky contacts to deteriorate and turn into ohmic-like contacts after a high temperature RTA process. 29,30 The channel mobility (μ ch ), current on/off ratio (I ON /I OFF ), threshold voltage (V T ) and Schottky barrier height (φ B ) were also extracted from the I-V characteristics and plotted with cumulative annealing temperature for further investigation (Figures 2c and 2d). μ ch was calculated using…”

New intracavity method for modulation of the polarization of laser radiation

“…In the study on Ti/n-GaAs Schottky diode by Everaert et al [16], they reported that contacts remained stable up to 300 ¡C and deterioration started at 300 ¡C. Furthermore, this contact was predicted to the thermodynamically unstable by Lau et al [17]. In investigation by Jin et al [18] on e †ects of hydrogenation on Ti/n-GaAs Schottky barrier, they have found that the value in SBD U b diode without hydrogenation (0.76 eV) is larger than that in the SBD with hydrogenation (0.58 eV) at 300 ¡C.…”