{"title":"Double-ended passivator enables dark-current-suppressed colloidal quantum dot photodiodes for CMOS-integrated infrared imagers","authors":"Peilin Liu, Shuaicheng Lu, Jing Liu, Bing Xia, Gaoyuan Yang, Mo Ke, Xuezhi Zhao, Junrui Yang, Yuxuan Liu, Ciyu Ge, Guijie Liang, Wei Chen, Xinzheng Lan, Jianbing Zhang, Liang Gao, Jiang Tang","doi":"10.1002/inf2.12497","DOIUrl":null,"url":null,"abstract":"<p>Lead sulfide (PbS) colloidal quantum dot (CQD) photodiodes integrated with silicon-based readout integrated circuits (ROICs) offer a promising solution for the next-generation short-wave infrared (SWIR) imaging technology. Despite their potential, large-size CQD photodiodes pose a challenge due to high dark currents resulting from surface states on non-passivated (100) facets and trap states generated by CQD fusion. In this work, we present a novel approach to address this issue by introducing double-ended ligands that supplementally passivate (100) facets of halide-capped large-size CQDs, leading to suppressed bandtail states and reduced defect concentration. Our results demonstrate that the dark current density is highly suppressed by about an order of magnitude to 9.6 nA cm<sup>−2</sup> at −10 mV, which is among the lowest reported for PbS CQD photodiodes. Furthermore, the performance of the photodiodes is exemplary, yielding an external quantum efficiency of 50.8% (which corresponds to a responsivity of 0.532 A W<sup>−1</sup>) and a specific detectivity of 2.5 × 10<sup>12</sup> Jones at 1300 nm. By integrating CQD photodiodes with CMOS ROICs, the CQD imager provides high-resolution (640 × 512) SWIR imaging for infrared penetration and material discrimination.</p><p>\n <figure>\n <div><picture>\n <source></source></picture><p></p>\n </div>\n </figure></p>","PeriodicalId":48538,"journal":{"name":"Infomat","volume":"6 1","pages":""},"PeriodicalIF":22.7000,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/inf2.12497","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Infomat","FirstCategoryId":"88","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/inf2.12497","RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Lead sulfide (PbS) colloidal quantum dot (CQD) photodiodes integrated with silicon-based readout integrated circuits (ROICs) offer a promising solution for the next-generation short-wave infrared (SWIR) imaging technology. Despite their potential, large-size CQD photodiodes pose a challenge due to high dark currents resulting from surface states on non-passivated (100) facets and trap states generated by CQD fusion. In this work, we present a novel approach to address this issue by introducing double-ended ligands that supplementally passivate (100) facets of halide-capped large-size CQDs, leading to suppressed bandtail states and reduced defect concentration. Our results demonstrate that the dark current density is highly suppressed by about an order of magnitude to 9.6 nA cm−2 at −10 mV, which is among the lowest reported for PbS CQD photodiodes. Furthermore, the performance of the photodiodes is exemplary, yielding an external quantum efficiency of 50.8% (which corresponds to a responsivity of 0.532 A W−1) and a specific detectivity of 2.5 × 1012 Jones at 1300 nm. By integrating CQD photodiodes with CMOS ROICs, the CQD imager provides high-resolution (640 × 512) SWIR imaging for infrared penetration and material discrimination.
期刊介绍:
InfoMat, an interdisciplinary and open-access journal, caters to the growing scientific interest in novel materials with unique electrical, optical, and magnetic properties, focusing on their applications in the rapid advancement of information technology. The journal serves as a high-quality platform for researchers across diverse scientific areas to share their findings, critical opinions, and foster collaboration between the materials science and information technology communities.