Influence of radiation energy on the response of a bipolar power transistor tested as dosimeter in radiation processing

The use of silicon devices as possible radiation monitors and/or dosimeters has been considered since many years because of the effect of ionizing radiation on the physical and electrical properties of these devices. A bipolar transistor investigated under standard laboratory conditions and in industrial irradiation plants having high-activity γ-source and high-energy, high-power electron beam was found to be suitable as routine radiation dosimeter. Tests carried out by irradiating the transistor with electron beams of energy ranging from 2.2 up to 8.6 MeV and 60Co γ-rays have shown that the response of this transistor is energy dependent. DLTS measurements have been performed on the irradiated devices to identify the recombination centers introduced by the radiation treatment. The influence of radiation energy on the behavior of this device is discussed.