硅基热电子短波红外探测技术(封面文章·特邀)

Silicon based hot electron short wave infrared detection technology(cover paperinvited)

短波红外具有穿透烟雾的特性,可在低光照环境或恶劣天气条件下成像,在军事、安防、环境监测等多个领域展现出重要应用价值。硅基热电子短波红外探测技术因具备与CMOS半导体工艺兼容、响应波段灵活可调等独特优势,已成为当前研究的热点。文中系统地回顾了该领域的国内外研究进展,剖析了与光电转换效率密切相关的热电子产生、传输与注入等物理过程中的能量损耗机制。在此基础上,总结了针对性的改进策略,包括通过光学吸收增强和热损耗抑制来增加热电子的产生效率;通过精确调控热电子的初始位置、能量、动量分布及自由程来优化其传输过程;以及利用肖特基结和界面调控等技术来提高热电子的注入概率。此外,文中还讨论了暗电流的抑制方法,以期提升探测器的整体性能。最后,展望了硅基热电子红外光电探测器未来的发展方向。

Significance Short wave infrared detectors,as a very important type of detector,play a crucial role in sensing and obtaining target image information.Their notable features include the ability to penetrate smoke,high spatial recognition,all-weather working ability,and applicability in harsh weather conditions,making it widely applicable in multiple fields of national major needs and national economic development.In the military field,shortwave infrared detectors,with their unique night vision and covert reconnaissance functions,have become a key tool for enhancing combat capabilities at night and in adverse weather conditions.In the field of security monitoring,it provides strong technical support for video monitoring under low or no light conditions,significantly enhancing security capabilities.In terms of environmental monitoring,these detectors provide valuable data support for environmental protection and climate research by accurately measuring specific components in the atmosphere.In addition,in the medical field,the application of shortwave infrared detectors in disease diagnosis has opened up new paths for medical technology innovation.Therefore,in-depth research on shortwave infrared detectors has important practical significance.ProgressTThis article systematically reviews the photoelectric conversion mechanism of Schottky photodetector,and summarizes and analyzes recent research results at home and abroad around the basic physical processes of hot electrons.This article first introduces the formation and basic characteristics of metal silicon Schottky junctions,and explores the three core processes of hot electron generation,transmission,and injection.Next,in terms of the generation of hot electrons,a review is conducted on the relevant work of researchers to improve the efficiency of hot electron generation through methods such as light absorption enhancement and thermal loss suppression.In terms of the transfer of hot electrons,the current proposed methods to control the initial position,initial energy and momentum,and mean-free path of hot electrons have been summarized to improve the transfer efficiency of hot electrons.In the injection method of hot electrons,strategies to improve injection efficiency such as multiple Schottky junctions and interface engineering were introduced.In addition,considering the crucial impact of dark current on detector performance,this article also explores current methods for suppressing dark current.Finally,this article provides an outlook on the future development direction of this field.ConclusionsandProspects Silicon-based hot electron detection technology holds the potential to broaden the response band of silicon to include the short-wave infrared band,while maintaining compatibility with siliconbased semiconductor processes.Its advantages,including low cost and high uniformity,bode well for its significant role in diverse fields such as military applications,security,and environmental monitoring.Looking ahead,it is imperative to delve deeper into the research of novel materials,structures,and mechanisms to further enhance the detector's performance.By focusing on developing new materials that can enhance the mean-free path of electrons and optimize the density of states,the transport efficiency of hot electrons can be boosted.Concurrently,the pursuit of innovative structures that efficiently absorb wide-spectrum infrared light,coupled with the optimization of the Schottky interface to increase hot electron injection efficiency and minimize dark current,is paramount.Moreover,exploring novel photoelectric conversion mechanisms that transcend the constraints of classical frameworks offers a promising avenue for pioneering advancements in infrared detection technology.