双束质子辐照砷化镓光电导探测器的I-V特性

 对用能量为7.5MeV和20MeV,注量为10¹¹～10¹³cm^-2的质子辐照后的砷化镓材料制作的光电导探测器的光电流和暗电流进行了测试，并由此推得电导率的变化。结果表明，经过能量为7.5MeV的质子改性后的砷化镓探测器相对于未改性的附加光电导率Δσ减少，而且随着辐照注量的增加而越小，而对于先用能量为20MeV质子辐照后再用能量为7.5MeV的质子辐照的砷化镓材料制作的探测器，其附加光电导率Δσ的减少则更为明显。对上述现象进行了分析，并根据其相应关系预测了该种探测器的响应时间、灵敏度、拖尾现象及受X射线激发的输出脉冲的后延的变化情况。

I-V Curve of GaAs photoconduction detector irradiated by double beams of proton

Dark current, photocurrent of GaAs detector before and after proton radiation with the energy of 7.5MeV and 20MeV have been measured.The result shows that when GaAs detectors are irradiated by proton with the energy of 7.5MeV, its resistance increases, and additional conductivity decreases when the dose of proton increases. This phenomenon is especially evident when GaAs detectors are irradiated in proper order by both beams of 20MeV and 7.5MeV proton. This phenomena and are some properties of this kind of detector are analyzed.