SILICON-ON-INSULATOR - AN EMERGING HIGH-LEVERAGE TECHNOLOGY

Silicon on insulator (SOI) has emerged as a high-leverage technology f or a wide range of commercial and military applications, While the use of SOI is presently limited to special niche applications, such as ra diation-hard space and defense electronics, thin-film SOI has become s trategic for low-power, battery-operated portable systems and large-sc ale integrated logic and memory circuits with sub-hair micron features , Substantial process simplification and cost reduction result from th e dielectrically isolated structures, Other important SOI applications are the merger of several functions on the same die that performs rel iably in adverse high-temperature environments, These include analog a nd logic functions, smart micromechanical sensors for automotive and d istributed jet engine control with logic functions, or smart high-volt age CMOS logic/control elements, Manufacturable solutions to several m aterial and device problems, however, must be demonstrated before SOI CMOS or BiCMOS designs enter the high volume commercial manufacturing stage, Among these are the availability, cost, and quality of SOI mate rial, gettering, electrostatic discharge protection, the floating-body problem in thin-film structures, and self-heating effects caused by t he low thermal conductivity of the buried-oxide layer. The status of S OI material is discussed, including the different methods used to prep are large SOI wafers, wafer availability, cost reduction strategies, m aterial characterization, and material quality, Applications and lever age areas are also described, with emphasis on problems and challenges that lie ahead for the large-scale manufacture of SOI products, The p otential economic impact of SOI technology on the profitability of sem iconductor manufacturing is described.