Harsh Environment Silicon Carbide UV Sensor and Junction Field-Effect Transistor

A harsh environment can be defined by one or more of the following: High temperature, high shock, high radiation, erosive flow, and corrosive media. Among all the harsh environment applications, high temperature applications have drawn lots of attention due to the emerging activity in automotive, turbine engine, space exploration and deep-well drilling telemetry. Silicon carbide has become the candidate for these harsh environment applications because of its wide bandgap, excellent chemical and thermal stability, and high breakdown electric field strength. This dissertation details the two building blocks of high-temperature UV sensing chip, namely Ultraviolet sensor and transistors. High temperature performance of silicon carbide metal-semiconductor-metal UV sensor is characterized at high temperatures for the first time. The sensor exhibits high photo-to- dark current ratio and fast rise and fall time even at high temperatures. Complementary SiC junction field-effect transistors of different gate configurations are proposed, fabricated and characterized from room temperature to 600 °C for the first time. High intrinsic gains at high temperatures suggest that complementary junction field-effect transistors are suitable devices for high temperature operational amplifier.