倒金字塔结构的黑硅PIN光电探测器的研究  

Study of black silicon PIN photo-detector with inverted pyramidal structure

作　　者：王锦[1] 陶科[2] 李国峰[1] 梁科[1] 蔡宏琨[1] WANG Jin;TAO Ke;LI Guo-fenga;LIANG Ke;CAI Hong-kun(Tianjin Key Laboratory of Optoelectronie Sensor and Sensing Network Technology ,College of Electronic Information and Optical Engineering,Nankai University,Tianjin 300071,China;Institute of Microelectronics,Chinese Academy of Scienees,Beijing 100029,China)

机构地区：[1]南开大学电子信息与光学工程学院,天津市光电传感器与传感网络技术重点实验室,天津300071 [2]中国科学院微电子研究所,北京100029

出　　处：《光电子．激光》2018年第12期1270-1274,共5页Journal of Optoelectronics·Laser

基　　金：南开大学2018年自制实验教学仪器项目(18NKZZYQ02).

摘　　要：由于晶体硅间接带隙的本质,光的吸收系数较低,影响了硅基光电探测器的量子效率。倒金字塔结构被证明是能够使得单晶硅片的光吸收效率接近Yablonovitch limit的有效陷光结构。本论文采用金属催化腐蚀技术在单晶硅上制备具有随机分布的倒金字塔陷光结构,并将其应用到PIN光电探测器。结果显示具有倒金字塔结构的黑硅PIN光电探测器加权平均反射率从20.18%降低至4.77%,探测器的漏电流仅0.9nA,光谱响应度达到0.64A/W,较常规硅探测器提高33%。这些结果表明金属催化腐蚀技术形成的倒金字塔结果能有效降低器件的表面反射率,从而提高探测器的光谱响应度。As a semiconductor with indirect band gap,the light-absorption coefficient of silicon is a little low,which limits the quantum efficiency of silicon based optoelectronic devices.Inverted pyramidal structure has been proved to be an effective light-trapping structure that can enhance the light absorption of silicon wafer close to Yablonovitch limit.In this work,random inverted pyramidal structures were fabricated on mono-crystalline silicon wafer by metal catalyzed etching technology,and integrated into PIN photo-detector to lower the reflectivity of PIN detector.The optical and electrical properties of PIN pho- to-detector are characterized.The results show that the size of those inverted pyramids ranges from 1μm -3μm,and the weighted average reflectivity of PIN photo-detector is decreased significantly from 20. 18%to 4.77%.The leakage current of the photo-detector is measured to only 0.9nA at room temperature.Furthermore,by adopting the random inverted pyramidal structure into the PIN photo-detector,the spectral response of 0.64A/W is achieved,which is improved by about 33% compared with that of con- ventional silicon detector.The experimental results demonstrate that the random inverted pyramidal structure prepared by metal catalyzed etching technology is beneficial to decrease the surface reflectance and finally improve the spectral response of PIN photodetectors.

关 键 词：PIN光电探测器 倒金字塔 金属催化腐蚀 表面陷光 

分 类 号：TN253[电子电信—物理电子学]