表面漏电流引起的噪声会限制CdZnTe(CZT)探测器的性能,尤其对于共面栅探测器,漏电噪声的大小与器件的电极设计和表面处理工艺密切相关.本文比较了探测器表面的物理和化学钝化工艺:采用H2O2溶液和KOH-KCl溶液对CZT样品进行湿化学钝化处理,采用RFPCVD法在CZT样品表面沉积类金刚石薄膜(DLC)进行物理干法钝化.借助俄歇电子能谱(AES)和显微拉曼光谱以及ZC36微电流测试仪等手段研究了CZT表面组成与器件电学性能之间的关系.AES结果表明KOH-KCl溶液钝化可以改善CZT样品表面的化学组分比,H2O2溶液钝化可以将表面富Te层转化为高阻氧化层,钝化前后的I-V特性曲线表明两种化学钝化方法均可以有效地减小器件表面漏电流,达到满意的钝化效果.CZT样品表面物理钝化通过在样品表面沉积DLC薄膜加以实现,显微拉曼光谱表明CZT表面钝化层是高sp3含量的DLC薄膜,AES深度剖析表明DLC薄膜可以有效阻止CZT内部元素的外扩散,并且DLC薄膜内部C元素向CZT内部的扩散也是比较低的.DLC薄膜钝化后的CZT共面栅探测器表面栅距25μm的栅间电阻可以达到12GΩ,有效地降低了器件的表面漏电流.
参考文献
[1] | Butler J.F.;Lingren C.L. .Cd/sub 1-x/Zn/sub x/Te gamma ray detectors[J].IEEE Transactions on Nuclear Science,1992(4):605-609. |
[2] | Chen H.;Hu Z.;Shi DT.;Wu GH.;Chen KT.;George MA.;Collins WE.;Burger A.;James RB.;Stahle CM.;Bartlett LM.;Tong J. .LOW-TEMPERATURE PHOTOLUMINESCENCE OF DETECTOR GRADE CD1-XZNXTE CRYSTAL TREATED BY DIFFERENT CHEMICAL ETCHANTS[J].Journal of Applied Physics,1996(6):3509-3512. |
[3] | MESCHER M.J.;SCHLESINGER T.E.;TONEY J.E. .Development of Dry Processing Techniques for CdZnTe Surface Passivation[J].Journal of Electronic Materials,1999(6):700-704. |
[4] | Chen KT.;Chen H.;Granderson B.;George MA.;Collins WE.;Burger A.;James RB.;Shi DT. .STUDY OF OXIDIZED CADMIUM ZINC TELLURIDE SURFACES[J].Journal of Vacuum Science & Technology, A. Vacuum, Surfaces, and Films,1997(3 Pt.1):850-853. |
[5] | Niemela A;Silila H;Ivanev V I .[J].Nuclear Instruments and Methods in Physics Research,1996,377:484-486. |
[6] | Shor A;Eisen Y;Mardor I .[J].Nuclear Instruments and Methods in Physics Research,1999,428(01):182-192. |
[7] | Lund J C;VanScyoc Ⅲ J M;James R B et al.[J].Nuclear Instruments and Methods in Physics Research,1996,380:256-261. |
[8] | George M A;Colilins W E;Chen K T et al.[J].Journal of Applied Physics,1995,77(07):3134-3137. |
[9] | Luke P.N. .Unipolar charge sensing with coplanar electrodes-application to semiconductor detectors[J].IEEE Transactions on Nuclear Science,1995(4):207-213. |
[10] | Kaushik C;Miguel H;Jean-olivier N et al.[J].Journal of Electronic Materials,2000,29(06):708-712. |
[11] | Chen H;Chattopadhyay K;Chen K T et al.[J].Journal of Vacuum Science and Technology A-Vacuum Surfaces and Films,1999,17:97. |
[12] | Sang Wenbin;Ju Jianhua;Shi Weiming et al.[J].Journal of Crystal Growth,2000,214/215:265-268. |
[13] | Fan Yimin;Ju Jianhua;Zhnag Weili et al.[J].Solid State Communications,2001,120:435-437. |
[14] | Dharmadasa I M;Blomfield C J;Gregory G E et al.[J].Surface and Interface Analysis,1994,21(10):718-723. |
[15] | Zhang Z J;Narumi K;Naramoto H.[J].Journal of Physics:Condensed Matter,1999(11):1273-1277. |
[16] | Li Wanwan;Sang Wenbin;Min Jiahua et al.[J].Semiconductor Science and Technology,2002,17(10):L55-L58. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%