This project proposes to explore the use of a wide bandgap semiconductor to make devices capable of operating at temperatures of at least 500øC. PN junctions will be fabricated. The major thrust will be the study of electrode technology to make OHMIC contacts that are stable at high temperature and in the presence of an electric bias. The appropriate metallization must resist both thermal diffusion and electromigration during operation at high temperatures. Ultimately, this research will lead to a bipolar transistor, probably of the NPN variety. Success with high-temperature OHMIC contacts will permit the fabrication of high-temperature Field Effect Transistors (FETs). These devices, both the bipolar and unipolar varieties, should be responsive to UV illumination, essentially permitting their operation as phototransistors or photo-FETs. We shall test the temperature stability of these devices up to 500øC and determine the maximum temperature at which such a structure can be operated.
Keywords: Wide Bandgap Semiconductors High Temperature Electronics
