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Engineering topics

Cheng, T. T.

Publications and source records attributed to Cheng, T. T..

Improved beta-SiC heteroepitaxial films using off-axis Si substrates

All beta-SiC films grown using on-axis (001) Si substrates that have been examined with transmission electron microscopy exhibit a high density of interfacial twins, stacking faults, and antiphase disorder. The antiphase boundaries can be decorated by chemical etching, sputter etching, wet oxidation, and beta-SiC growth in the presence of diborane. All traces of antiphase disorder are eliminated when the heteroepitaxial growth is carried out on vicinal (001) Si substrates that are tilted 2 deg about a 110-line axis. In addition, growth on the off-axis Si produces beta-SiC films that are significantly smoother than on-axis films. The density of stacking faults is apparently unaffected by growth on the off-axis substrates.

Powell, J. A.↗

Lattice defects in beta-SiC grown epitaxially on silicon substrates

Defects generated on beta-SiC grown on a (001) silicon substrate by chemical vapor deposition are characterized and their mechanism of formation discussed. It is argued that nucleation plays a primary role in this heteroepitaxial system where the lattice mismatch is so large.

Pirouz, P.↗

Microscopy of epitaxially grown beta-SiC on 001-plane silicon

Various defects occurring in epitaxially grown layers of beta-SiC are characterized by TEM, and the mechanisms of growth and defect formation are discussed. In particular, attention is given to the following types of defects: misfit dislocations, interfacial twins, antiphase boundaries, threading dislocations, and wide stacking faults. Details of the experimental procedure are given.

Pirouz, P.↗