Abstract: This article studies the unidirectional electric behavior and special electrical characteristics of germanium semiconductor cut in electrial discharge machine(EDM) processing. It establishes an EDM model and utilized respectively diodes, variable resistors, voltage regulator tubes, resistors and other devices to characterize the contact potential barrier, inter electrode bulk resistance, and discharge maintaining voltage of the dielectric and the resistance of the dielectric. In addition, it designes a special fixture for the wire-cut electrical disharge machine(WEDM) of germanium. By means of coating carbon plasma on the surface of germanium and meanwhile using a graphite block as an electrode, the contact potential barrier and contact resistance are reduced, and blowing at the electrical contact points reduced the production of non-conductive passive film to ensure the smooth performance of EDM. Finally, a WEDM experiment is carried out on an N-type germanium specimen with a resistivity of 22.3 Ω·cm and a height of 170 mm, with a cutting efficiency of more than 100 mm2/min, and a special shape germanium window is obtained by a numerical control machine. This article also testes the discharge waveform, analyzes the WEDM characteristics of germanium semiconductors.

Key words: germanium, semiconductor, electrical discharge machine, wire-cut, mode