Blanket and patterned growth of CdTe on (211)Si substrates by metal-organic vapor phase epitaxy

Metalorganic vapor phase epitaxy (MOVPE) of (211)B CdTe on (211)Si using intermediate Ge and ZnTe layers has been achieved for use as substrates for the growth of HgCdTe infrared detector materials. The best (211)B CdTe films grown in this study display a low X-ray diffraction (XRD) rocking-curve full-width-at-half-maximum (FWHM) of 64 arcs for a 12 µm thick layer and Everson etch pit density (EPD) of 3x105cm-2. In order to reduce the threading dislocation density further, growth on patterned layer has been investigated using Si3N4 as the mask. In order to achieve selective nucleation on patterned layer, process parameters were first developed. A circular pattern was used to study the anisotropy during growth and to identify the optimum orientation for parallel stripe growth windows. The optimum growth window was then used for the growth of completely merged layers (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)