On the growth of 4H-SiC by low-temperature liquid phase epitaxy in Al rich Al-Si melts

The growth of 4H-SiC by low-temperature liquid phase epitaxy was studied in AI-Si melts. The temperature ranged from 1000degreesC to 1200degreesC. Some problems, which were sources of non-homogeneity of the growth or low reproducibility of the process, were identified and reviewed: (1) local delayed wetting of the seed by the melt, (2) morphological (3) presence of alumina particles on the liquid, (4) high reactivity of the melt with graphite at temperature above 1200degreesC, (5) formation of crystallites on the surface upon cooling. The solutions proposed to avoid or limit these problems are: (1) deposition of a Si layer before the growth, (2) careful backside gluing, (3) a two-step procedure involving the pre-dipping in the melt of a graphite rod on which alumina particles agglomerate, (4) growth at temperature lower than 1200degreesC. No solution was found to avoid the crystallites formation upon cooling. (C) 2003 Elsevier Science B.V. All rights reserved.