The investigation of the grain structure is important to understand the origin of dislocations during crystal growth of multicrystalline silicon. This paper studies the dislocation density distribution for different grain orientations that occur during crystal growth. Single grains are analyzed in detail, including their microstructure. The grain orientations are determined by means of the electron backscatter diffraction technique. The obtained information reveals grain orientations, which allow a higher number of active slip planes during crystal growth process. The number of active slip planes during solidification seems to influence the dislocation density in the final crystal.

An experimental study of the correlation between dislocations, grain orientation, and grain boundaries in multicrystalline silicon (mc‐Si) bulk crystals is presented. Selected mc‐Si samples revealing typical structural patterns like clustering or line‐up of dislocations in the vicinity of grain boundaries are measured by electron backscatter diffraction (EBSD). The orientation of dislocation slip planes and twin boundary planes as well as the relationship between the misorientation of neighbouring grains and the spatial alignment of dislocations are analyzed on the basis of the relevant pole figures calculated from EBSD scans. The effect of grain boundaries on the behaviour of dislocations seems to be related to the presence or absence of a common slip system on both sides of the boundary and hence, to the type of lattice misorientation between involved grains. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Summary The determination of grain boundary planes in multicrystalline material has only been restricted to transmission electron microscope investigations (Jang et al., 1992; Elgat et al., 1985) or to metallograpical investigations of the grain boundary (Randle et al., 1993). The first method is expensive, and both are complex and time consuming in grain boundary preparation. This paper proposes the determination of grain boundary planes in semiconductor wafer by a combined application of Electron Back Scatter Diffraction and Infrared Transmission Microscopy. In particular, the new method is demonstrated with directional solidificated multicrystalline silicon.