4H-SiC电流型探测器对^(60)Co源γ射线的响应研究

Gamma Sensitivity of A 4H-SiC Detector in Current Mode

为研究4H-SiC电流型探测器对γ射线的探测性能,采用4H-SiC制成肖特基二极管,并利用60Co源形成的强γ辐射场研究其对γ射线的响应特性及其影响因素。实验结果表明,当外加反向电压为195 V时,4H-SiC探测器漏电流仅为11.4 pA/cm2,远低于Si基探测器漏电流。当4H-SiC探测器置于强γ辐射场时,由γ射线导致的信号电流为249 nA,比本底信号电流大5个量级。同时4H-SiC探测器在零偏压时也能对γ射线产生明显的信号,均值电流为85 nA。随工作电压增大,4H-SiC探测器的γ响应随之增大。结合4H-SiC探测器体积小、响应快、耐高温和耐辐照等特点,可将4H-SiC探测器用于强钴源点注量在线监测等方面。

A Schottky barrier diode was made using 4H-SiC wide band gap material,which is both radiation resistance and temperature resistance,excellent due to its intrinsic properties.The gamma sensitivity of the 4H-SiC Schottky barrier diode was investigated by irradiating the diode with gamma rays from60 Co source.The leakage current of the detector is 11.4 pA /cm2,when a reverse bias of 195 V is applied.The gamma induced current is 249 nA when the 4H-SiC detector is irradiated by60 Co gamma rays.The detector is able to detect gamma rays at zero bias,with a induced current of 85 nA.The gamma sensitivity of the 4H-SiC detector increases with reversed bias.