Antimonide-Based Composite-Channel HFETs

The binary compound semiconductors, InSb and InAs, along with their related alloys with similar lattice constants are candidates for high-speed, low-power electronic devices. Applications could include high- speed analog and digital systems used for data processing, communications, imaging, and sensing, particularly in portable equipment such as hand-held devices and satellites. The development of Sb-based transistors for use in low-noise high-frequency amplifiers, digital circuits, and mixed-signal circuits could provide the enabling technology needed to address these rapidly expanding needs. However, a drawback of the technology is the low breakdown voltage associated with the relatively narrow band-gap InAs channel. Added with staggered band lineup at InAs/AlSb heterojunction, the generated holes from the breakdown cannot be confined in the channel and result in significant effects on device performance. In this work, we propose an alternative approach of composite channel to alleviate this issue. Device design, growth, fabrication and characterization will be described in details.