Proton radiation and thermal stability of gallium nitride and gallium nitride devices.

摘要

In today's industry one can see a constant challenge to exceed the limits of yesterday's devices. For the last three decades, the III-V nitride semiconductors have been viewed as highly promising for semiconductor device applications. The primary focus of III-V nitrides, thus far, has been centered on light emitting diodes (LEDs), injection lasers for digital data reading and storage applications, and ultra violet photodetectors. Yet, another application is high-power electronic devices for space-borne communications systems. It is expected that GaN-based devices will be more resistant to radiation damage often encountered in space environments, though verification of this is just now being undertaken. In particular, no information is yet available about the sensitivity to radiation of devices using dielectrics such as MOSFETs. Similarly, very limited data has been reported on the effects of high-energy protons on GaN based devices of any type. For this reason the research presented in this dissertation was undertaken to study the radiation and thermal stability of gallium nitride materials and gallium nitride semiconductor diodes, with and without novel gate dielectrics such as, scandium oxide (Sc2O 3) and magnesium oxide (MgO) and the ternary mix of magnesium calcium oxide (MgCaO).; It was found that though environmental degradation could be a problem for MgO dielectrics, the radiation exposure itself did not produce significant damage in either the Sc2O3, MgO or MgCaO dielectrics. Much of the minimal damage occurred in the GaN as shown by photoluminescence spectroscopy (PL).