{"title":"Dark Current Transport and Junction Capacitance Mechanism in InP One-Side Junction Photodiodes","authors":"Wei He;Zhongjun Jiang;Liang Wang","doi":"10.1109/LPT.2024.3464865","DOIUrl":null,"url":null,"abstract":"Photodiodes serve as pivotal components in optical data links, where minimized dark current and junction capacitance is vital for improving the detection sensitivity and response speed of the devices. This study experimentally and theoretically demonstrates that the one-side junction photodiode (OSJ-PD) exhibits reduced dark current and diminished junction capacitance. Notably, the device has a capacitance density of \n<inline-formula> <tex-math>$2.2 \\times 10^{-4}\\ \\mathrm {pF} / \\mu \\mathrm {m}^{2}$ </tex-math></inline-formula>\n and a dark current density of \n<inline-formula> <tex-math>$2.4 \\times 10^{-5}\\ \\mathrm {nA} / \\mu \\mathrm {m}^{2}$ </tex-math></inline-formula>\n at −5 V bias. Numerical simulations of current-voltage characteristics reveal that Shockley-Read-Hall (SRH) and trap-assisted tunneling (TAT) currents dominate dark current at low reverse bias from 0 V to −14 V, while band-to-band tunneling (BBT) current prevails at higher reverse bias from −14 V to −20 V. This study, for the first time, explains the trend of the variation in the dark current curve with bias voltage based on the generation mechanisms of dark current. Furthermore, we have theoretically demonstrated that the dark current of the OSJ-PD is insensitive to defect density at low voltages, and attributed the low junction capacitance to the wide depletion layer nature of the OSJ-PDs. These findings provide a comprehensive understanding of carrier transport and give a demonstration to analyze the current variation within diverse photodiodes.","PeriodicalId":13065,"journal":{"name":"IEEE Photonics Technology Letters","volume":null,"pages":null},"PeriodicalIF":2.3000,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"IEEE Photonics Technology Letters","FirstCategoryId":"5","ListUrlMain":"https://ieeexplore.ieee.org/document/10684735/","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, ELECTRICAL & ELECTRONIC","Score":null,"Total":0}
引用次数: 0
Abstract
Photodiodes serve as pivotal components in optical data links, where minimized dark current and junction capacitance is vital for improving the detection sensitivity and response speed of the devices. This study experimentally and theoretically demonstrates that the one-side junction photodiode (OSJ-PD) exhibits reduced dark current and diminished junction capacitance. Notably, the device has a capacitance density of
$2.2 \times 10^{-4}\ \mathrm {pF} / \mu \mathrm {m}^{2}$
and a dark current density of
$2.4 \times 10^{-5}\ \mathrm {nA} / \mu \mathrm {m}^{2}$
at −5 V bias. Numerical simulations of current-voltage characteristics reveal that Shockley-Read-Hall (SRH) and trap-assisted tunneling (TAT) currents dominate dark current at low reverse bias from 0 V to −14 V, while band-to-band tunneling (BBT) current prevails at higher reverse bias from −14 V to −20 V. This study, for the first time, explains the trend of the variation in the dark current curve with bias voltage based on the generation mechanisms of dark current. Furthermore, we have theoretically demonstrated that the dark current of the OSJ-PD is insensitive to defect density at low voltages, and attributed the low junction capacitance to the wide depletion layer nature of the OSJ-PDs. These findings provide a comprehensive understanding of carrier transport and give a demonstration to analyze the current variation within diverse photodiodes.
期刊介绍:
IEEE Photonics Technology Letters addresses all aspects of the IEEE Photonics Society Constitutional Field of Interest with emphasis on photonic/lightwave components and applications, laser physics and systems and laser/electro-optics technology. Examples of subject areas for the above areas of concentration are integrated optic and optoelectronic devices, high-power laser arrays (e.g. diode, CO2), free electron lasers, solid, state lasers, laser materials'' interactions and femtosecond laser techniques. The letters journal publishes engineering, applied physics and physics oriented papers. Emphasis is on rapid publication of timely manuscripts. A goal is to provide a focal point of quality engineering-oriented papers in the electro-optics field not found in other rapid-publication journals.