Pd-InGaAs as a new self-aligned contact material on InGaAs

Introduction. Self-alignment of source/drain (S/D) contacts to the transistor gate is important, as it brings the S/D contacts close to the channel and allows the achievement of low parasitic S/D series resistance R_SD. Low R_SD is needed for high-mobility and short-channel transistors where the channel resistance is low and external resistance is a significant proportion of the total resistance between source and drain. Fig. 1 illustrates the self-aligned S/D contact metallization process for InGaAs transistors. Recently, the first self-aligned Ni-InGaAs S/D contacts were demonstrated.^{1, 2} In this work, Pd-InGaAs is explored as a new self-aligned contact metallization technology.