Development of wide-bandgap semiconductor-based dosimeter for LET distribution measurement in carbon therapy filed

This paper presents a proof of concept of silicon carbide (SiC), a type of wideband semiconductor, based dosimeter for linear energy transfer (LET) distribution measurement at clinical carbon beam therapy field. SiC Schottky barrier diode (SBD), which has been designed for ionization detector, was utilized for spectroscopy of pristine 290 MeV/u 12C heavy ion therapy beams at Gunma University Heavy Ion Medical Centre (GHMC) facility, Japan. Measurement of LET distribution was successfully demonstrated at different depth with developed SiC SBD dosimeter. Also SiC SBD was exposed with clinical carbon beam with high intensity condition. Through CCE and deep level defect evaluation, sufficient radiation tolerance was examined for SiC SBD for futuristic usage in clinical carbons. Those results suggested that preliminary evaluation of SiC SBD was successful as energy-dispersive dosimeter for heavy ion therapy field.