Growth and characterization of 6' InSb substrates for use in large area infrared imaging applications

摘要

In this paper we report on an industry first; the growth and characterization of 6" diameter indium antimonide (InSb) substrates that are suitable for use in the fabrication of MWIR focal plane infrared detectors. Results will be presented on the production of single crystal 6" InSb ingots grown by the Czochralski (Cz) technique. We will also assess the electrical quality of new 6" InSb crystals and present uniformity information on Hall mobility, resistivity and carrier level from which we will infer comparisons on the relative dark current performance of the material grown. High quality, epitaxy-ready type surfaces have been prepared and we will demonstrate how the key surface quality characteristics of roughness (＜ 0.5 nm rms), oxide thickness (＜100 A) and flatness (＜7 μm TTV) have been maintained across production processes that scale 4" to 6" wafer formats. We conclude by presenting our road map for the development of large area.InSb substrates and describe how developments in Czochralski crystal growth and surface finishing technology will support industry's requirements to deliver higher performance, large format IR focal plane array type devices.