Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard-brittle, grayish-white metalloid in the carbon group, chemically similar to its group neighbours silicon and tin. Pure germanium is a semiconductor with an appearance similar to elemental silicon. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature.
ASTROHN Technology Ltd specialists have developed a large-diameter infrared (IR) lens. This caused the need to obtain a single crystal of germanium of a sufficiently large diameter (about 200 mm) for the manufacture of an input lens. In addition, the problem of high structural excellence of the workpiece was critical. Therefore, the workpieces must be single-crystal, so that internal defects do not weaken the passage of the beam. Such blanks can only be obtained using the Czochralski method. There is [...]