基于MOCVD外延超薄氧化镓薄膜的高性能日盲和X射线探测器(特邀)  

High-performance Solar-blind and X-ray Detector Based on Ultra-thin Gallium Oxide Film Grown by MOCVD(Invited)

作　　者：钟天晟 于舜杰 赵晓龙 丁梦璠 梁方舟 方师 张中方 侯小虎 孙海定 徐光伟 胡芹 龙世兵 ZHONG Tiansheng;YU Shunjie;ZHAO Xiaolong;DING Mengfan;LIANG Fangzhou;FANG Shi;ZHANG Zhongfang;HOU Xiaohu;SUN Haiding;XU Guangwei;HU Qin;LONG Shibing(School of Microelectronics,University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]中国科学技术大学微电子学院,合肥230026

出　　处：《光子学报》2021年第10期203-214,共12页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.61925110,U20A20207,61821091,62004184,62004186,51961145110);中国科学院战略性先导研究项目(No.XDB44000000);中国科学院前沿科学重点研究计划(No.QYZDB-SSW-JSC048);广东省重点领域研究与发展计划(No.2020B010174002);中央高校基本科研业务费专项资金(Nos.WK2100000014,WK2100000010);中国博士后科学基金项目(Nos.2020M671895,BX20200320)。

摘　　要：为了顺应光电探测器和阵列小尺寸、多功能、高密度集成的发展趋势,报告了一种基于超薄氧化镓(Ga2O3)制成的高性能日盲和X射线双功能探测器。基于金属有机化合物化学气相沉淀法,通过高温下的精细生长调控,实现了较薄厚度(70 nm)的高质量Ga2O3异质外延薄膜。得益于Ga2O3的超宽禁带和薄膜的高质量,基于此薄膜制备的金属-半导体-金属结构光电探测器在日盲紫外探测方面实现了5.5×10^(7)的光暗电流比,4.65×10^(15)Jones的探测率,3.53×10^(4)%的外量子效率,72.2 A/W的响应度,而且上述日盲紫外探测参数在不同的日盲光强下(14.7~548μW/cm^(2))保持相对稳定;在X射线探测方面实现了1.91×10^(4)μC·cm^(-2)·Gy^(-1)的超高灵敏度,在等效厚度的情况下,超过之前报道的Ga2O3薄膜器件。同时,器件在较低的工作电压下,依然可以维持较高的综合性能。通过系统分析,薄膜质量的提升、本征氧空位电离和光致肖特基势垒降低效应等因素共同导致器件表现出针对日盲紫外和X射线的优良探测性能。此外,X射线诱导的级联效应也是超薄Ga_(2)O_(3)具备高X射线探测灵敏度的主要因素之一。该工作可为今后兼具高性能、低功耗的超薄日盲和X射线探测器提供有益的参考。Complying with the trend of small size,multi-functionality,and high density integration of photoelectric detectors and arrays,a high-performance solar-blind and X-ray dual function detector basedon ultra-thin Ga2O3 was reported.Based on the metal-organic chemical vapor deposition,through fine tuning of growth at high temperature,a thin thickness(70 nm)of high-quality gallium oxide heteroepitaxial thin film is realized.Owing to the ultra-wide band gap of Ga2O3 and the high quality of the film,metal-semiconductor-metal structure photodetector based on this film has achieved a photo-to-dark current ratio of 5.5×10^(7),detectivity of 4.65×10^(15) Jones,external quantum efficiency of 3.53×10^(4)%,and responsivity of 72.23 A/W in solar-blind ultraviolet detection band.What's more,the above-mentioned solar-blind ultraviolet performances remain stable relatively at different solar-blind light intensities(14.7~548μW/cm^(2)).While for X-ray detection,an ultra-high sensitivity of 1.91×10^(4)μC·cm^(-2)·Gy^(-1) is achieved,which exceeds the previously reported Ga2O3 thin-film detectors under the equivalent thickness.Besides,the device can still achieve comprehensively high performance at a lower operating voltage.The improvement of film quality,ionization of intrinsic oxygen vacancies,and photoinduced Schottky barrier reduction effect etc.conribute to the excellent photoresponse performance of this Ga_(2)O_(3) thin-film detectors under both solar-blind and X-ray illumination.Additionally,the cascade effect casused by the X-ray induced high-erergy electrons is another critial aspect for the high X-ray sensitivity of the device.This work provides potential inspirations for ultra-thin solar-blind and X-ray detectors with high performance and low power consumption in the future.

关 键 词：光电探测器 双功能探测 MOCVD 氧化镓 X射线 日盲紫外 

分 类 号：O472.8[理学—半导体物理]