Platinum and Rhodium Silicide–Germanide Optoelectronics

Abstract

Since the introduction of SiO2/Si devices in the 1960s, the only basic change in the design of a MOSFET has been in the gate length. The channel thickness has fundamentally remained unchanged, as the inversion layer in a silicon MOSFET is still about 10 nm thick. Bipolar transistor base widths have been of sub-micron dimensions all this time. It is time for a new property to be exploited in concert with the high mobility strained-silicon channels and silicon–germanium alloys. This property is the inherently low parasitic series resistance of Schottky barrier contacts. Schottky contacts, beam leads, and microbridges, while originally developed in silicon, have been successfully integrated into compound semiconductors for optoelectronics. Reintroduction of these technologies in optoelectronics based on silicon–germanium is proposed. Several new applications using platinum and rhodium compounds of silicon and germanium are presented.