CAJ | 학술논문

基于3片不同条件下生长的CdZnTe晶片制备出平面电极(Planar)探测器CZT1、CZT2及CZT3.分析室温下3个探测器在不同场强作用下对低能X/γ射线的光谱响应,并结合相应晶体材料的载流子迁移特性和掺杂剂的浓度以及存在状态,归纳影响探测器分辨率的原因.掺杂In浓度高的探测器CZT1,由于材料中存在的深能级缺陷Cd2+i,作为电子的俘获中心,影响了载流子的收集效率,进而降低了探测器的能量分辨率;掺杂In浓度低的探测器CZT2对不同能量X/γ射线均具有较好的能量分辨率;而Al掺杂探测器CZT3,由于Al间隙原子Ali的存在作为电子的散射中心,最终影响了收集效率及能量分辨率.
기우3편불동조건하생장적CdZnTe정편제비출평면전겁(Planar)탐측기CZT1、CZT2급CZT3.분석실온하3개탐측기재불동장강작용하대저능X/γ사선적광보향응,병결합상응정체재료적재류자천이특성화참잡제적농도이급존재상태,귀납영향탐측기분변솔적원인.참잡In농도고적탐측기CZT1,유우재료중존재적심능급결함Cd2+i,작위전자적부획중심,영향료재류자적수집효솔,진이강저료탐측기적능량분변솔;참잡In농도저적탐측기CZT2대불동능량X/γ사선균구유교호적능량분변솔;이Al참잡탐측기CZT3,유우Al간극원자Ali적존재작위전자적산사중심,최종영향료수집효솔급능량분변솔.
Three CdZnTe planar detectors, named CZT1, CZT2 and CZT3 respectively, were fabricated based on the as-grown CdZnTe wafers grown with different dopant conditions. The low energy X/γ-ray spectral responses of the detectors were obtained under various electrical field strengths at room temperature. The energy resolution of the detectors was evaluated by combining the charge transport properties of the materials and the dopant behaviors. The deep level trapping centers of Cd2+i have been tentatively recognized as the electron trapping centers, hence deteriorating the resolution. Low In concentration doped CZT2 exhibits excellent X/γ-ray spectral resolution and charge transport properties, which implies a lower density of trapping centers in the crystal. In Al doped CZT3,however, a critically uncompleted charge carrier collection and in turn the reduced energy resolution is likely attributed to the scattering of the ionized aluminum interstitial Ali.