HgCdTe intrared detectors

Abstract

Significant advances in the areas of mercury cadmium telluride (HgCdTe)-material growth, detector array fabrication, and readout integrated circuit design and fabrication have been accumulated over the past years. These advances have led to the demonstration of high resolution-, low-noise-, and large-format reliable focal plane arrays (FPA). In the 1–3 μm short wavelength infrared region, high-performance, reliable 1024×1024 FPA for astronomy applications have been developed and 2048×2048 arrays are in development. In the 3–5μm middle wavelength infrared spectral region, high-performance 640×480 and 1024×1024 FPA have been developed, while 256×256 FPA are in continuous production to support systems applications. In the 8–12μm- and beyond long-wavelengthinfrared region, high performance, 128×128 FPA have been developed on CdZnTe substrates. The molecular beam epitaxy (MBE) HgCdTe-based technique has emerged as a viable technology for manufacturing high-performance infrared focal plane arrays. Device-quality liquid phase epitaxy, metalorganic chemical vapor deposition, and MBE material are being grown routinely for applications in the 1.5–16.0 μm spectral region. An excellent control of composition, growth rate, layer thickness, doping concentration, dislocation density, and transport characteristics has been demonstrated in FPA.