An array of transfer length measurement (TLM) structures was formed on an electrically isolated (0001) n+6Hα-SiC epilayer. The n+6Hα-SiC epilayer contained an in situ incorporated nitrogen concentration of 4×1019 cm−3. The specific contact resistance (ρc), sheet resistance (Rs), contact resistance (Rc), and transfer length (LT) were calculated from resistance (RT) versus contact spacing (d) measurements obtained from 17 TLM structures. The linear curves used for these calculations were fit to the RT versus d data by calculating the standard error of linear regression of RT on d; where, the average correlation coefficient with a straight line was 1.0000 and the average standard error of linear regression of RT on d was 0.08 Ω. The resulting average values were: ρc=1.30×10−5 Ω cm2, Rs=14.4 Ω/square, Rc=1.6 Ω, and LT=9.5 μm. The (111) TiC contacts, epitaxially grown by chemical vapor deposition, were thermally and chemically stable at 1400 °C. The TiC contacts could not be scratched with a tungsten carbide scriber, nor delaminated from the 6Hα-SiC substrate.

A 6Hα-SiC crystal sample, which has a surface amorphous layer resulting from a high-dose Ga implantation, was heated using a pulsed excimer laser at several energy fluences. At an energy fluence of 1.66 J/cm2, the in situ reflectivity measurement of the surface during laser processing indicates that melting of the SiC surface has occurred. Rutherford backscattering and channeling analysis shows that the molten amorphous SiC recrystallizes using the substrate as a seed, and that the recrystallized layer has good crystal quality. Secondary-ion mass spectrometry measurements indicate that the melting, resulting from the excimer laser pulse, results in significant redistribution of the implanted Ga. This result, the first reported for SiC, suggests that the pulsed ultraviolet process can anneal the implantation damage through a melt recrystallization process, and thus could be used to dope SiC through a gas phase adsorption process.

Silicon carbide (SiC) thin films were deposited on titanium carbide (TiC) substrates by pyrolysis of 1,3 disilacyclobutane (C2H8Si2), at atmospheric pressure, in an inverted-vertical cold-wall chemical vapor deposition reactor. The growth rate, morphology, and crystallinity of the films were studied, at constant C2H8Si2 flow rate, as a function of substrate temperature (810 °C≤Ts≤1285 °C). The growth rate increased with increasing Ts. Film morphologies were dependent on Ts and slight differences in TiC substrate orientation at Ts≥1015 °C. A smooth, soft as-grown morphology was obtained at 810 °C. Hard, rough as-grown surfaces were obtained at Ts≥1066 °C. Films grown at Ts ≥1066 °C contained a SiC primary phase and a Si-rich second phase. Epitaxial growth of β-SiC was obtained only at 1210 °C.

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The defects and crystallinity of as-grown and annealed TiCx (grown by the high-pressure float-zone) were examined by TEM and double crystal x-ray rocking curves. Three types of subboundaries and planar defects within subgrains were observed in as-grown TiCx. Subboundaries are classified by structure as (i) wide-extended, fault-like defects (WEFLD's), (ii) edge dislocation arrays, and (iii) dislocation networks. Planar defects were observed at dislocation nodes of subboundaries and also within subgrains; this is the first reported observation of planar defects within TiCx subgrains. The misorientation and/or density of subgrains in TiCx was reduced significantly by annealing at 2300 °C in contact with graphite.