Dislocation structure in interfaces between Si wafers with hybrid crystal orientation

Abstract

AbstractDislocation structure in Si(110)/Si(001) wafer bonding (WB) structures have been studied by transmission electron microscopy (TEM). The behavior of intermediate native oxide layers during high temperature annealing, the nature of interfacial dislocations and dislocation generation mechanisms are the main issues of this work. Samples were fabricated by direct hydrophilic WB of 200 mm wafers with native oxide. The as‐bonded structures containing 140‐nm thick layers were thermally annealed in the temperature range 1150 to 1200 °C. The dislocation structure composed of a pattern of unidirectional parallel but broken dislocation arrays is formed in the structures with partial or entire dissolution of the oxide layer. The contrast of broken dark lines usually observed in TEM bright field micrographs is supposed to be caused by integral effect of steps compensating twist misorientation and arrays of 60‐degree dislocations. We suggest that nucleation of dislocation loops at the interface due to the agglomeration of intrinsic point defects is a plausible mechanism of dislocation generation. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)