For the past several years hydrogen incorporation in metal oxide semiconductor (MOS) devices has been of interest because studies have shown that vacuum annealing of oxidized Si substrates desorbs hydrogen, revealing interfacial defects. Today, in applications that require higher power and/or temperature, Si will likely be replaced with a wide-band-gap semiconductor. For MOS devices, SiC is a leading contender because it can be thermally oxidized to form a SiO2 insulating layer similar to Si. However, the SiC/SiO2 structure potentially contains hydrogen sensitive centers similar to those found in Si/SiO2 structures. Using electron paramagnetic resonance (EPR), we have observed a center 1.8 G wide peak-to-peak at g=2.0026. The center is generated in oxidized SiC that has received a 900° C dry, N2 or O2, post oxidation heat-treatment in which moisture is measured to be less than 1 ppm. Annealing at 900° C in standard Ar containing at least 50 ppm H2O decreases the center's concentration by two orders of magnitude. By comparing results from our study to studies of Si-H and C-H bonds in a-SiC:H [1] and SiC converted graphite [2], we suggest that this center is related to carbon dangling bonds created by the effusion of hydrogen during the dry heat-treatment. We will compare the activation energy for the hydrogen depassivation of our center with that found for other C-H and Si-H systems.

Epitaxial layers of low doped 4H-SiC are implanted with 20 keV 2H+ ions to a dose of 1×1015 cm−2. The samples are subsequently annealed at temperatures ranging from 1040 to 1135 °C. Secondary ion mass spectrometry is used to obtain the concentration versus depth profiles of the atomic deuterium in the samples. It is found that the concentration of implanted deuterium decreases rapidly in the samples as a function of anneal time.

The experimental data are explained by a model where the deuterium migrates rapidly and becomes trapped and de-trapped at implantation-induced defects which exhibit a slightly shallower depth distribution than the implanted deuterium ions. Computer simulations using this model, in which the damage profile is taken from Monte Carlo simulations and the surface is treated as a perfect sink for the diffusing deuterium atoms, are performed with good results compared to the experimental data. The complexes are tentatively identified as carbon-deuterium at a Si-vacancy and a dissociation energy (ED) of approximately 4.9 eV is extracted for the deuterium-vacancy complexes.

The effect of the incorporation and annealing of deuterium in 3C-SiC on its photoluninescence is reported. A 3C-SiC crystal has been implanted with 100 keV deuterium and subsequently annealed at temperatures between 1015 °C and 1220 °C for 1 to 5 minutes. SIMS depth profiles indicate hydrogen is strongly trapped by defects generated through ion bombardment, but a gradual damage repairing occurs during annealing. Photoluminescence was measured with 488 nm Ar laser excitation for sample temperatures from 89 K to 400 K. The PL peak wavelength of 540 nm at room temperature has shifted to 538 nm at 89 K. The peak PL intensity decreases with measurement temperature while its full width at half maximum (FWHM) exhibits an increasing trend. PL data were taken at five annealing stages. The post-implantation peak PL intensity and its integrated area increase initially with annealing temperature and time. After the final annealing at 1218 °C for 2 minute, PL intensity and its integrated area exhibit a decrease in level.