Injection velocity in thin-channel InAs HEMTs

We have experimentally extracted the virtual-source electron injection velocity in InAs HEMTs with a 5 nm thick channel. For long gate lengths, these devices exhibit noticeably worse injection velocity than thicker channel devices of a similar design. However, for very short gate lengths, as the devices approach the ballistic regime, the extracted injection velocity becomes rather independent of channel thickness. From these results, we can conclude that InAs-based QW-FETs with very thin channels have the potential of scaling to very short dimensions.