GaAs Digital IC´s for Multigigabit´s Systems

Superfast computers with subnanosecond cycle times, multigigabit´s telecommunication and instrumentation systems are some of the main applications that forces microelectronics into the submicron age. It is now generally taken for granted that more than one technology is needed to meet these goals. GaAs IC´s after a long infancy, are thus emerging as being complementary to fast submicron bipolar and MOSFET IC´s. Based on normally-off MESFET´s, hetero FET´s (HEMT´s, undoped HEMT´s), or HBT´s, they are becoming of age thanks to major breakthroughs such as high uniformity material, improved surface processing and more flexible and refined designs. In terms of LSI performances, GaAs digital IC´s have been extensively demonstrated up to a few thousand gates to exhibit a 2 to 3 times higher speed or a 3 to 5 times lower power consumption than their silicon counterparts with equivalent feature sizes¹. Nevertheless, there is still a lot of room for improvemnent, especially in memory design and interconnect technology, before achieving ultimate performances with GaAs digital IC´s.