a-Se薄膜在X-ray照射下的光衰特性研究  

Photoelectric Attenuation Properties of a-Se Film to X-ray

作　　者：郭震[1] 张观明[1] 

机构地区：[1]武汉大学物理科学与技术学院,湖北武汉430072

出　　处：《武汉大学学报（理学版）》2002年第5期597-600,共4页Journal of Wuhan University:Natural Science Edition

基　　金：湖北省自然科学基金资助项目 (2 0 3 90 5 3 2 )

摘　　要：依据光电导与弛豫时间成反比变化的理论 ,在蒸发温度为 2 2 0℃的条件下用真空沉积法制备了多块厚度不同的a Se薄膜 ,对其在X ray照射下的光衰效应进行实验研究 .实验结果表明a Se薄膜在厚度较小时其灵敏度随厚度的增加而增加 ,在 2 75～ 4 5 7μm之间时 ,a Se灵敏度存在极大值 .实验结果对基于a Se薄膜光电导特性的探测器的性能优化有一定的指导作用 .According to the theory photoconduction change in inverse proportion to the time of relaxation. Under the condition of 220℃ in temperature of evaporating, We have prepared much different pieces of thickness amorphous selenium film with the depositing law of vacuum, and have carried on experiments to study the voltage decays of the film under X ray irradiation. The experimental result shows the sensitivity of amorphous selenium film increase with increase of the thickness when the thickness is thin. The sensitivity of amorphous selenium film will appear maximum, when the thickness is between 275 to 457 μm. Experimental result has certain guidance functions to optimize detectors on the basis of the photoconduction character of the amorphous selenium film.

关 键 词：a-Se薄膜 X-ray照射 灵敏度 真空沉积法 光衰效应 光电导性 医学影像 

分 类 号：R445[医药卫生—影像医学与核医学] O484.4[医药卫生—诊断学]