ion implantation in silicon has been widely used in the production of semiconductor devices and integrated circuits in china. research of low energy ion implantation, high energy ion implantation and the soi technology is in progress. fully si-implanted planar gaas dual-gate mesfets, high linear gaas hall effect sensors, light emitting diodes, laser devices, and infrared detectors made of hgcdte have been fabricated by ion implantation and have been applied in telecommunication, transportation, medicine, and in a ground satellite station. the research of ion implantation in metals began in 1978 in china. ion implantation for improving wear, corrosion, oxidation, fatigue-resistance and secondary electron emission characteristics has progressed. the artificial joints treated by ion implantation have been used in trial medical treatment. this films of high t/sub c/ superconductors of y/sub 1/ba/sub 2/cu/sub 3/o/sub 7/ with a zero resistance temperature of 86 k have been worked out with reactive ion beam coating. recently, ion beam enhanced deposition has been used to synthesize si/sub 3/n/sub 4/ and other compound films. the process of ion beam enhanced deposition has been studied by a dynamic ion implantation model and monte carlo computer simulation. it was at the end of the 1960s that china began to work on ion implantation china now has more than 80 units involved in the field of research and application of ion implantation, including scientific research institutes, universities and factories