Authors: D L Medlin N Y C Yang
Publish Date: 2011/12/21
Volume: 41, Issue: 6, Pages: 1456-1464
Abstract
At present little is known concerning the atomicscale structure of grain boundaries in Bi2Te3 and related thermoelectric materials As twins are perhaps the simplest possible type of grain boundary they provide a good starting point for studies of interface structure in this class of materials Here we present an electron microscopic study of an interfacial step observed at a 0001 basal twin boundary in Bi2Te3 We discuss the crystallography of defects at twins in Bi2Te3 by considering the geometric implications for differently terminated step arrangements and comparing the defect configurations anticipated for deformation and annealing/growth twins Finally we consider the observed defect in this framework and discuss its relationship to analogous features in facecenteredcubic metals namely the 112type interfaces that are commonly observed terminating 111 growth and annealing twins in these materials This analysis provides insight concerning the relationships of dislocations to twin formation and morphology in Bi2Te3
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