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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 m thick layer and Everson etch pit density (EPD) of 3x10(expn 5) cm(expn -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., Published in Physica Status Solidi, 15 May 2012. Prepared in collaboration with Brimrose Corp. of America, Sparks, MD, Rensselaer Polytechnic Institute, Troy, NY and Agiltron Corp., Woburn, MA.

Epitaxial lateral overgrowth of CdTe was carried out on Si and GaAs substrates. Perfectly selective epitaxial growth was demonstrated on CdTe/Si and GaAs substrates using Si3N4 as the mask material. Selective growth has been possible at T>5OO deg C and pressure <30 Torr. Lateral to vertical growth rate ratio of >3 has been achieved. Reduction in defect density in films has been demonstrated., Original contains color plates: All DTIC reproductions will be in black and white.

The papers in this special issue of the Journal of Electronic Materials were presented during the 1994 U.S. Workshop on the Physics and Chemistry of Mercury Cadmium Telluride and Other IR Materials that was held at the Hyatt Regency Hill Country Resort, San Antonio, TX, October 4-6, 1994. This workshop was the thirteenth in a series which began in October 1981. Over that time, it has become the preeminent forum for open interdisciplinary discussion of scientific and technological issues concerning HgCdTe and other Hg-based IR materials. Subject areas discussed at the 1994 workshop include substrate technology, epitaxial material growth, surface and interface properties, defects, electrical and noncontact optical characterization. Forty-three of the 57 papers presented at the workshop appear in this publication.

This report summarizes work done over a five-year period on a program entitled, Research on Mercury Cadmium Telluride. Using the alloy growth OMVPE process, we have obtained compositional uniformity of 0.005 over a 2 GaAs slice. p-type doping to 10 17/cm3 and n-type doping to 4 x 10 18/cm3 have been achieved using As and In respectively. Annealing studies have shown that the background concentration of undoped HgCdTe is around 5 x 10 14/cm3. Passivation techniques, using anodic sulfidization, have been developed for HgCdTe. Both p-n diodes and field effect transistors have been demonstrated on material grown during the course of this program. A diffusion length of 120 microns has been measured in material with x = 0.3.