The silicon /silicon carbide system is a compound semiconductor/oxide system which yields reasonably good metal oxide silicon field effect transistors (MOSFETs). It may be useful as a model system in exploring challenges inherent among all compound semiconductor/oxide interfaces. The interface/near interface defects in compound semiconductors are poorly understood. For several years, with several coworkers, we have explored silicon carbide based MOSFETs with electrically detected magnetic resonance (EDMR), [1-4] establishing a connection between a near featureless isotropic EDMR spectrum with g=2.003 and deep level defects in the interface/near interface region of SiC MOSFETs. We tentatively linked the spectrum to a silicon vacancy or closely related defect. Through multiple improvements in EDMR hardware and data acquisition software, we have achieved a very large improvement in sensitivity and resolution in EDMR, which allows us to detect side peak features in the EDMR spectra caused by electron nuclear hyperfine interactions. This improved resolution allows far more definitive conclusions to be drawn about defect structure. We have made high resolution ESMR measurements on a series of SiC transistors prepared under very different processing conditions. The EDMR results show nearly identical side peak structure in all cases, strongly suggesting that the side peaks and central line are associated with the same defect and also strongly suggesting that this defect is widely important in SiC MOSFETs. The high resolution EDMR traces also show a slight but real anisotropy in the spectra. The high resolution EDMR measurements show a strong central line, two comparatively strong near side peaks, and a second pair of much weaker side peaks located twice as far from the central line as the inner side peaks. The conventional EPR literature on large volume SiC samples consistently links a five line spectrum a strong central line, two comparatively strong near side peaks, and a second pair of much weaker side peaks located twice as far from the central line as the inner side peaks to silicon vacancy centers. The SiC MOSFET EDMR interface spectrum follows this pattern, but only qualitatively. Conventional EPR measurements made on large volume samples indicate a spacing between the lines which is less than half of what we observe and also indicate relative amplitudes of the five lines of about 0.04, 0.26, 1, 0.26, 0.04. Our EDMR measurements indicate a center line to inner side peak ratio significantly larger. The discrepancies between our EDMR results and the conventional large volume EPR results could plausibly be interpreted in terms of a rather gross level of disorder near the interface.