Observation and first-principles calculation of buried wurtzite phases in zinc-blende CdTe thin films

We report direct observation of the existence of buried thin wurtzite CdTe layers in nominally pure zinc-blende CdTe thin films using high-resolution transmission electron microscopy. The formation of the buried wurtzite laye rs is a result of the formation of high density of planar defects in the zi nc-blende films-the wurtzite layers are formed by closely spaced lamellar t wins. First-principles calculations reveal that the presence of the buried wurtzite layers may be responsible for the poor electrical properties of th e polycrystalline zinc-blende CdTe films. (C) 2000 American Institute of Ph ysics. [S0003-6951(00)04836-1].