| In addition to the observed hydrogen passivation of shallow impurities in SiC crystals, it is important to know whether, and how, hydrogen present in the epi-reactor can passivate doping impurities during growth of the material. Variations in hydrogen incorporation can affect the net doping density and make process control difficult. This makes it essential for technologists to understand the process of hydrogen passivation and its effects on the doping concentration in the crystal.; To understand this phenomenon, a process has been developed to intentionally hydrogenate SiC crystals by striking a hydrogen plasma using the Reactive Ion Etching (RIE) System in the Emerging Materials Research Laboratory at MSU. Photoluminescence (PL) and Capacitance—Voltage (CV) were used to determine the effect of hydrogen incorporation on dopants in the SiC crystal lattice. Crystal annealing was performed at 1000°C using the Thermco Oxidation Furnace to drive hydrogen out of the lattice (a process referred to as “de-hydrogenation”). PL and CV measurements were taken to look for changes in the hydrogen concentration as well as free carrier concentration, respectively. (Abstract shortened by UMI.)... |
