碲化镉新型β-射线探测器的研制

A New Type CdTe β-Ray Detector

本文介绍一种新型的β—射线探测器的制造过程及其特性.采用背吸杂技术有效地降低了器件的反向漏电流并提高了成品率,提出并应用真空镀铜工艺制作P型碲化镉的低阻接触,取得了良好的效果,该探测器由一个PN结二极管构成.在20℃,2V的电压下其反向漏电流小于3.5X10^(-12)A/mm^2,在60℃,2V的电压下其反向漏电流小于3.5×10^(-11)A/mm^(2),因而探测器可在60℃下正常工作.在标准^(85)Krβ—射线源上获得了1.65×10^(-9)A的输出电流。

In this paper we describe the fabrication and characteristics of a new type CdTe β-raydetector. Taking back-absorption of impurity, we make the reverse current of the detector lowerand increase the rate of finished products. We not only propose but also apply the vacuum coatingcopper to make the low resistivety contact on P CdTe, the result of the research shows that it iseffective. The detector consists of a PN-junction diode, its reverse current is less than 8. 8 ×10-12A/mm2 at 2V and 20℃, less than 3. 5 × 10-11A/mm2 at 2V and 60℃, so it can operateeffectively at 60℃. An output current of 1. 65 × 10-8A has been achived with standard 85Krβ-radiation source, the cut-off frequency is higer than 2 300 Hz.