Ultrahigh-speed HEMT LSI technology

The current status of HEMT (high-electron mobility transistor) technology for high-performance VLSI is presented, focusing on device structure in the submicrometer-dimensional range, a self-aligned HEMT LSI processing, and HEMT LSIs implemented in a supercomputer system. The 1.1 K gate bus driver logic LSI has been developed to demonstrate the high-speed data transfer in a highly parallel processing system at room temperature, operating at 10.92 GFLOPS speed. A cryogenic 3.3 K gate random number generator logic LSI with maximum clock frequency of 1.6 GHz has also been developed to demonstrate the high-clock-rate system operations at liquid nitrogen temperature. With submicrometer gates, as well as advanced materials technologies, a HEMT 64 kb static RAM with subnanosecond access operation and a 10 K-gate logic LSI with subhundred-picosecond logic delays are possible.<>