[19a-W810-1~10] 2.2 Detection systems

△ [19a-W810-6] Development of an ultra-thin diamond membrane detector for ionized particle measurement -(2)

〇Wataru Kada¹, Tomihiro Kamiya², Veljko Grilj³, Natko Skukan³, Ivan Sudic³, Michal Pomorski⁴, Takahiro Makino², Yushi Ando^1,2, Yuya Kambayashi^1,2, Shinobu Onoda², Osamu Hanaizumi¹, Milko Jaksic³, Takeshi Ohshima² (1.Gunma Univ, 2.JAEA, 3.RBI, 4.CEA- LIST)

Keywords:diamond membrane,focused ion beam,charge collection efficiency

In this study, an ultra-thin single crystal diamond membrane detector was developed. Under focused ion beam irradiation condition, temporal decrease in charge collection efficiency (polarization) has been reported with conventional ionized particle detector based on diamond. To suppress the effect of polarization, a membrane detector structure with partially etched region with thickness of several μm was introduced for the detector design of single crystal diamond. With the benefit of membrane design, it is possible to form an electric field significantly higher than ± 1V/μm in diamond detector, which is expected to have a saturated CCE in conventional diamond detector. Compared to the existing single-crystal diamond charged particle detector, excellent radiation resistance was obtained with diamond membrane detector under high bias application (±5 V/μm) with suppression effect of polarization. Moreover, amplitude of charge pulse signals was different from the saturated value with much higher electrical filed of ±20 V/μm.