Theoretical explanation of the control of the Schottky barrier height using an ultrathin interface metal layer

Abstract

Recently experimental results for a thin interface metal layer to control the Schottky barrier height of Ti/Pt/n-GaAs and Pt/Ti/n-GaAs contacts were presented [X. Wu, M. T. Schmidt, and E. S. Yang, Appl. Phys. Lett. 54, 268 (1989)]. In the present letter a possible explanation of the variation of the Schottky barrier height of the bi-metal-semiconductor contact is presented on the basis of the modification of the theory of the single-layer metal-semiconductor contact for the multilayer metal-semiconductor contact. This model leads to an acceptable agreement between our theoretical results and the experimental results presented in the above-mentioned paper and in an earlier publication [M. Hagio, H. Tagaki, A. Nagashima, and G. Kano, Solid-State Electron. 22, 347 (1979)].