抄録
The response of chemical vapor deposited (CVD) diamond thin film to focused ionized particle irradiation was investigated in order to evaluate the film's use as a transmission detector for heavy ion hits from azimuthally varying field (AVF) cyclotron at the Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency. A spectroscopic grade Single-Crystalline (SC) CVD diamond film with thickness of 50 μm was prepared and characterized by using an ion beam-induced charge (IBIC) system with a 3 MeV H+ microbeam and a transient ion beam-induced current (TIBIC) system with a 15 MeV O4+ microbeam. The IBIC signals decreased significantly during a short period of microbeam irradiation, whereas the signal responded satisfactorily to the alpha particles from an 241Am radiation source. The peak degradation due to microbeam irradiation was quickly recovered by releasing the bias. These effects can be explained by terms of polarization due to charge capture by defects in the SC-CVD diamond.
