This Small Business Innovation Research (SBIR) Phase I project will investigate silicon carbide (SiC) on insulator technology, which is similar to that of silicon on insulator (SOI). Interest is rapidly increasing in wide bandgap semiconductors for superior high frequency and high power electronics. SiC is the most advanced wide bandgap semiconductor from a materials and device processing point of view. However, many device applications, especially high frequency devices, require insulating or semi-insulating substrates for optimum performance. However, there are currently no semi-insulating SiC substrates. Phase I will develop a SiC on insulator, and instead of silicon dioxide (SiO2), aluminum nitride (AlN) will be used as the insulator. AlN has a wide bandgap of 6.2 eV and is virtually insulating in its as-deposited form. Another potential use for this material system is as an insulator in metal-insulator-semiconductor (MIS) devices as an alternate to SiO2 for use at high temperatures. In Phase I this structure will be grown on a common hexagonal polytype (6H-SiC) substrates. Phase II would further develop this technology and examlne transistor performance on these SiC on insulating substrates. Commercial applications are expected in cost-effective and reproducible manufacture of high-performance, high-frequency devices using SiC on insulator technology. AlN may also be a useful insulator for MIS structures which must operate at high temperatures.
