High performance Si/Si1-xGex resonant tunneling diodes

Resonant tunneling diodes (RTDs) with strained i-Si0.4Ge0.6 potential barriers and a strained i-Si quantum well, all on a relaxed Si0.8Ge0.2 virtual substrate were successfully grown by ultra high vacuum compatible chemical vapor deposition and fabricated using standard Si processing methods. A large peak to valley current ratio of 2.9 and a peak current density of 4.3 kA/cm(2) at room temperature were recorded from pulsed and continuous dc current-voltage measurements, the highest reported values to date for Si/Si1-xGex RTDs. These de figures of merit and material system render such structures suitable and highly compatible with present high speed and low power Si/Si1-xGex heterojunction field effect transistor based integrated circuits.