Published online by Cambridge University Press: 15 February 2011
CdTe thin films with thicknesses in the range of 60˜100 nm have been grown on miscut (001) Si surfaces under different precursors, such as Te and As, with one cycle annealing. The thin-film microstructure was studied in cross section using high-resolution electron microscopy. Atomicresolution images revealed several interesting features of the initial growth of the heteroepitaxial CdTe thin films. With As as the precursor, the films initially grew in three different orientation variants (commonly referred to as domains): (A) CdTe (111)//Si (001) with CdTe (1–10)//Si(110); (B) CdTe (111)//Si (001) with CdTe (11–2)//Si(110), and (C) CdTe (001) // Si (001) with CdTe (110) // Si (110). Each variant has demonstrated its own characteristic defects such as twinning, interface Lomer dislocations and {111} stacking faults. With the [001] growth direction, the CdTe film became defect-free by having about 13° tilt relative to Si [001] such that CdTe (1–11) and Si(−111) planes aligned sideways at the interface. With Te as the precursor, A- and B-type variants were mainly observed. The interfaces were sharper, especially for the A-type interface, but the film adhesion was weaker than when As was the precursor.