Abstract: An epitaxial structure and method of manufacture for a infrared detector device with low dislocation density, especially for high performance large area focal plane arrays. Preferably, the epitaxial structure includes a buffer layer comprising a Hg-based II-VI material and an overlayer comprising a detector comprising a Hg-based II-VI material. The buffer layer is transparent at the operating frequencies of the detector.

Abstract: A metalorganic arsenic source comprising R.sub.3-m AsH.sub.m, where R is an organic radical selected from the group consisting of C.sub.n H.sub.2n+1 and C.sub.n H.sub.2n-1, where n ranges from 1 to 6, and where m is 1 or 2, such as tert-butylarsine (t-BuAsH.sub.2), is useful in terminating a silicon surface with arsenic without carbon contamination, thereby permitting subsequent growth of high quality ZnSe. Use of this metalorganic arsenic source allows the full potential of the metalorganic molecular beam epitaxy (MOMBE) deposition technique, which has demonstrated superior flux control than that achieved by MBE, to be realized in the heteroepitaxy of HgCdTe on silicon substrates. Other metalorganic deposition procedures, such as MOVPE, may also be employed in the practice of the invention.