新结构1x4线阵列X光探测器的研究

Abstract-A new-type line array x-ray detectors have been investigated in this project. Those detectors, fabricated on the high-resistivity silicon substrate, have an "edge on" strip configuration. Its space resolusion is 5 strips per millmeter. The architecture of this kind of detectors can overcome the drawbacks of small absorption coefficient of silicon material for high energy x-ray. It was demonstrated that those detectors can be used to detect the 59 keV energy peak of Am241 radioactive source. The detectors in this study achieved a "dead region" as short as 150mm by using a special guard ring structure. This guard ring structure is benefit not only to enhance the detection quantun effciency, but also to reduce the leakage current of the detectors. Experiments showed that the float-zone silicon has potential advantages to be used to fabricate high gain bipolar devices, such as bipolar detectors. This was atributed by the facts that the detrimental defects is few, and the lifetime of minority carriers are very high in the high purity float-zone silicon crystal. A X-ray bipolar detector on high purity float zone silicon demonstrated high gain up to 3820 for X ray from a 1 mCi Cd radioactive source. When it operated as a phototransistor, high gain of 3660 for 45pW light was observed.

我们提出并将研制一种新结构1x4线阵列X光探测器.它将采用单晶硅材料,”拉通型”雪崩光电二极管以及端面入射结构.器件的分辨率优于5对线/mm,每个探测元件的面积小于100微米x100微米,可探测能量高至30KeV的X光.它具有高量子效率,高灵敏度,较高分辨率,低噪声,结辜虻?制作成本低廉等优点..