First-Principles Calculation for Interfacial Energy of Void Defect in CZ Silicon Crystal

Abstract

By means of first principles calculation we studied the interfacial energy of void defects which were formed during the crystal cooling process in a Czochralski(CZ) puller. In this study the interfacial structure of void defect was assumed to be either a vacuum/oxide film/Si(111) structure or a vacuum/Si(111) structure. The calculation result showed that the interfacial energy was 0.886 Jm -2 in the case with an oxide film. It was close to the value(0.830 Jm -2 ) which was derived from the viewpoint of void defects formation around 1373 K. And it was 1.551 Jm -2 in the case without an oxide film, which was twice as large than an interface with an oxide film. For the range of Si crystal growth conditions for semiconductor use, we calculated the size and density of void defects with the interfacial energy which was obtained from first principles calculation in the case with an oxide film. The results agreed with the experimental results.