PERFORMANCE AND APPLICATIONS OF THE 14 MEV ELECTRON-RADIATION LINAC AT CIAE

A 14 MeV electron linear accelerator which was designed and manufactur ed by the China Institute of Atomic Energy (CIAE) has been modified in to an radiation processing accelerator in 1987. It consists of an elec tron gun, two prebunchers, one buncher, a three meter long acceleratin g section, and a 90 degree bending magnet. The linac is S-band (2856 M Hz), travelling wave accelerator driven by a Chinese-made klystron. Th e energy of electrons can be adjusted from 8 MeV to 18 MeV and the ave rage beam power is about 2 kW. The beam width is 600 mm and the unifor mity of scanning beam is better than 10%. The linac is used to irradia te power semiconductor devices for controlling the minority carrier li fetime (MCL). More than twenty factories and scientific institutions u se this linac to irradiate silicon controlled rectifiers (SCR) and the fast recovery diodes (FRD), and more than 0.2 million pieces of SCR h ave been irradiated. Tests have also been carried out for colour-chang e of topaz.