31. High-purity germanium ( HPGe ) detectors typically have higher sensitivity. 32. The germanium isotope emits two weak gamma rays and a conversion electron. 33. Appreciable gallium and germanium may also be incorporated into the crystal structure. 34. Early investigations into low bandgap semiconductors focused on germanium ( Ge ). 35. Similar structures have been found with silicon, germanium or arsenic heteroatoms. 36. Common semiconductor materials include silicon, germanium and gallium arsenide. 37. P-type point contact ( PPC ) germanium detectors are used. 38. That time the production of germanium was classified as a secret one. 39. Germanium is usually considered to be a metalloid rather than a metal.40. Germanium can be derived from certain minerals and from the ashes of coal.
