Mercury-doped germanium

From the exit slit, the beam is directed to either of two detectors by the movable mirror behind the exit slit. Typical detectors are InSb, a photovoltaic indium antimonide detector operated at 77 K, and He Ge, a photo-conductive mercury-doped germanium detector maintained at 15 K by a closed-cycle helium refrigerator... 

Borello and Levenstein (1962) Preparation and Properties of Mercury-Doped Germanium by S. R. Borello and H. Levenstein, J. Appl. Phys. 33, 2947-2950. 

Bode and Graham (1963) A Comparison of the Performance of Copper-Doped Germanium and Mercury-Doped Germanium Detectors by D. Bode and H. A. Graham, Infrared Phys. 3, 129-137. 

Photon detectors consist of a thin film of semiconductor material, such as lead sulfide, lead telluride, indium antimonide, or germanium doped with copper or mercury, deposited on a nonconducting glass and sealed into an evacuated envelope. Photon flux impinging on the semiconductor increases its conductivity. Lead-sulfide detectors are sensitive to radiation below about 3 fj.m in wavelength and have a response time of about 10 /nsec. Doped germanium detectors cooled to liquid-helium temperatures are sensitive to radiation up to about 120 jitm in wavelength, and have a response time of approximately 1 nsec. 

In their conductive state, conducting polymers are either too sensitive to air and moisture (as is the case for polyacetylene) or may have conductivities well below that of wiring metals. Only polyacetylene reaches a conductivity of over 10 S cmr, comparable with iron. Polypyrrole or polyaniline have conductivities less than mercury and similar to doped germanium. Poly(p-phenylenevinylene) (PPV), which will be discussed in Section 11.4.2, is yet another polymer labeled conducting even... 

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