Buried CxSi layers were produced by the high-energy implantation of C into Czochralski-type material. The C depth-distribution, the morphology of the buried layers, and the precipitation of C were investigated as functions of rapid thermal annealing (700 to 1300C) by performing transmission electron microscopic, secondary ion mass spectrometric and positron annihilation measurements. It was found that, at temperatures below about 800C, vacancy agglomerates as well as metastable C-Si agglomerates were present. Precipitates of -SiC were observed at higher temperatures. The results were explained in terms of interactions between C atoms and irradiation-induced defects.

P.Werner, S.Eichler, G.Mariani, R.Kögler, W.Skorupa: Applied Physics Letters, 1997, 70[2], 252-4