Morphological and electrical characterization results are presented for cubic SiC films grown by chemical vapor deposition on single-crystal Si substrates. The films, up to 40 ~m thick, were characterized by optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron channeling, surface profilometry, and Hail measurements. A variety of morphological features observed on the SiC films are described. Electrical measurements showed a decrease in the electron mobility with increasing electron carrier concentration, similar to that observed in St. Room temperature electron mobilities up to 520 cm2/V-s (at an electron carrier concentration of 5 • 10 TM cm -~) were measured. Finally, a number of parameters believed to be important in the growth process were investigated and some discussion is given of their possible effects on the film characteristics.

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This paper updates on-going experimental and theoretical investigations of non-micropipe defects imaged by synchrotron white beam X-ray topography (SWBXT) in SiC devices and epitaxial layers. Computer-based thermal modeling of screw-dislocation related breakdown in SiC diodes has been initiated to gain insights into internal temperature profiles as a function of microplasma power. A preliminary study of epitaxial 4H- and 6H-SiC p+n mesa diodes indicates that very low angle boundaries, whose electrical properties have not previously been reported, do not significantly impact DC I-V properties (forward and reverse) measured at biases less than 70% of the SiC breakdown field. The presence of very small growth pits on the surface of commercial 4H-SiC epitaxial layers, almost undetectable by high magnification optical microscopy, was revealed by atomic force microscopy and found to correspond to the locations of closed core screw dislocations imaged by SWBXT.