Mercury cadmium telluride

Kidder L H, Levin I W, Lewis E N, Kleiman V D and Heilweil E J 1997 Mercury cadmium telluride focal-plane array detection for mid-infrared Fourier-transform spectroscopic imaging Opt. Lett. 22 742-4... 

DTGS = deuterated triglycine sulfate KRS — 5 = mixed thallium bromide-iodide LT = lithium tantalate MCT = mercury cadmium telluride and OPO = optical parametric oscillator. 

Commonly used II-VI compounds include zinc sulfide, zinc selenide, zinc telluride, cadmium sulfide, cadmium telluride, and mercury cadmium telluride. These materials are not as widely used as the III-V compounds, one reason being that it is difficult to achieve p-type doping. Mercury cadmium telluride is used extensively in military night sights, which detect in the 8-13 im spectral band (a similar material, platinum silicide, is being developed for that purpose). The major applications ofCVD II-VI compounds are found in photovoltaic and electroluminescent displays. 

Volume 5 Mercury Cadmium Telluride Imagers (by A. Onshage)... 

The source is usually a temperature-stabilized ceramic filament operating around 1500K. The detector in FTIR is usually a deuterium triglycine sulphate (DTGS) detector, although in RAIRS experiments the liquid nitrogen-cooled mercury cadmium telluride (MCT) detector is employed. 

The experiments described here were performed with a Digilab FTS40 Fourier transform instrument, with a liquid nitrogen-cooled Mercury Cadmium Telluride, (MCT), detector. The instrument is provided with a computer for data acquisition, storage and mathematical treatment. P-polarized incident light was obtained by means of an A1 wire-grid polarizer supported on a BaF2 substrate. 

Donald Long and Joseph L. Schmit, Mercury-Cadmium Telluride and Closely Related Alloys... 

W.F.H. Micklethwaite, The Crystal Growth of Cadmium Mercury Telluride Paul E. Petersen, Auger Recombination in Mercury Cadmium Telluride R.M. Broudy and V.J. Mazurczyck, (HgCd)Te Photoconductive Detectors M.B. Reine, A.K. Sood, and T.J. Tredwell, Photovoltaic Infrared Detectors M.A. Kinch, Metal-Insulator-Semiconductor Infrared Detectors... 

FT-IR microspectroscopy is a new nondestructive, fast and rehable technique for solid-phase reaction monitoring. It is the most powerful of the currently available IR methods as it usually requires only a single bead for analysis, thus it is referred to as single bead FT-IR [166]. (See also Chapter 12 for further details). The high sensitivity of the FT-IR microscope is achieved thanks to the use of an expensive liquid nitrogen-cooled mercury cadmium telluride (MCT) detector. Despite the high cost of the instrument, this technique should become more widely used in the future as it represents the most convenient real-time reaction monitoring tool in SPOS [166, 167]. 

Mullin JB, Irvine SJC (1994) Metalorganic Vapor-Phase Epitaxy of Mercury Cadmium Telluride. Progress in Crystal Growth and Characterization of Materials 29(1-4), 217-252... 

Singh HB, Sudha N (1996) OrganoteUurium precursors for metal organic chemical vapour deposition (MOCVD) of mercury cadmium telluride (MCT). Polyhedron 15(5-6), 745-763... 

J. Brice and P. Capper, eds., Properties of Mercury Cadmium Telluride, Institution of Electrical Engineers (INSPEC), London, 1987. 

Indium antimonide/Mercury cadmium telluride (InSb/MCT) sandwich. IR filters ... 

Mercury-cadmium-telluride is the principal semiconductor now being used in advanced infrared systems, both for military and other surveillance applications. Its preparation and use in infrared detectors and arrays was the subject of Volume 18 of this treatise. New generations of detectors and arrays require sophisticated epitaxial growth, which in turn requires precise phase diagram data. 

FTIR Microspectroscopy.3 A microscope accessory coupled to a liquid-nitrogen-cooled mercury-cadmium-telluride (MCT) detector can be used to obtain an IR spectrum. This is possible in both the transmission and reflectance modes. Several beads are spread on an IR-transparent window (NaCl, KBr, diamond) and possibly flattened via a hand-press or a compression cell. The IR beam is focused on a single bead using the view mode of the microscope. The blank area surrounding the bead is isolated using an adjustable aperture, and a spectrum is recorded using 32 scans (<1 min). A nearby blank area of the same size on the IR transparent window is recorded as the background. 

A photoconductive detector is a semiconductor whose conductivity increases when infrared radiation excites electrons from the valence band to the conduction band. Photovoltaic detectors contain pn junctions, across which an electric field exists. Absorption of infrared radiation creates electrons and holes, which are attracted to opposite sides of the junction and which change the voltage across the junction. Mercury cadmium telluride (Hg,. Cd/Te, 0 < x < 1) is a detector material whose sensitivity to different wavelengths is affected by the stoichiome-try coefficient, x. Photoconductive and photovoltaic devices can be cooled to 77 K (liquid nitrogen temperature) to reduce thermal electric noise by more than an order of magnitude. 

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