Germanium test procedures

IEEE 1996. Institute of Electrical and Electronics Engineers. Report No. 325-1996. IEEE Standard Test Procedures for Germanium Gamma-Ray Detectors. Posted online at iee-explore.ieee.org in 2002. 

The International Electrotechnical Commission published detailed instructions for testing of semiconductor detectors. For gamma-ray detectors, the lEC Publication 656 (1979), "Test Procedures for High-Purity Germanium Detectors for X and Gamma Radiation" can be ordered from the Bureau Central de la Commission E1ectrotechnique Internationale, 1, rue de Varembe, Geneve, Suisse. 

Independent tests have been made in a search for possible contamination of the (100) face of a germanium crystal from the ambient during the cleaning procedure, since halfintegral-order diffraction beams were observed in the (110) azimuth. 

Currently accepted standard procedures fa- testing germanium detectors are given in the following report, available from The Institute of Electrical and Electronic Engineers, Service Center, 445 Hoes Lane, PO Box 1331, Piscataway, NJ 08855-1331, USA ... 

Procedure. A drop of the alkaline or slightly acid test solution is treated, on a spot plate or filter paper, with a drop of the molybdate solution, and then with a drop of 0.1 % acetic solution of benzidine in order to form the benzidine salt of germanimolybdic acid. The mixture is then buffered with a few drops of a saturated solution of sodium acetate, or, when the test is carried out on filter paper, held over ammonia. A light or dark blue stain is formed, according to the amount of germanium present. 

Procedure. Amberlite IRA-411 (Cl form, 30 mesh) is digested in a solution of 21 mg haematoxylin in 20 ml 0.5 N hydrochloric acid containing 2 ml of ethanol. The yellow resin is put into a drop of the test solution on a spot plate. In the presence of germanium (in 0.1-3 N HCl) a violet to black coloration appears on the surface of the resin. 

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