基于阻挡层结构外延材料的InGaAs探测器的可见-短波红外光谱拓展方法研究

The lattice of ternary alloy InxGa1-xAs can match with that of InP substrate perfectly, when the x of In component is 0.53. The spectral response of detectors based on In0.53Ga0.47As is from 0.9μm to 1.7μm,which work at room temperature with high performance. The spectral irradiance of moonlight and air glow is mainly in the wavelength region from visible to SWIR band. The imaging for very low background applications during this wavelength range is of great significance in civil safety and defense field. An important developing direction of InGaAs detectors in developed countries is to reduce the thickness of the InP substrate. Then, a greater percentage of visible light could be captured by the detectors. This kind of detector integrates the visible to SWIR response and the imaging system could be simplified. Related research results are reported in foreign countries, but their research methods, technologies and products embargo strictly to China. Now we have not seen such research reports in China. This project proposes a spectral extension method for uncooled short wave infrared focal plane arrays with very low dark current. Research work will take place in the field of epitaxial wafer structure with etch-stop layer, substrate removing with low damage, multilayer anti-reflection film design and its spectral characteristics coupled with detectos, dark current generation mechanism and suppression methods, etc. These research will allow visible irradiance to reach InGaAs absorption layer and then to be detected. As a result, the detection spectrum of uncooled InGaAs focal plane array will be extended toward visible spectrum from 0.4μm to 1.7μm. At the same time, the dark current will be depressed to a low level. The research work will lay good foundation for independent development and innovation of core photoelectric sensors in China.

In组分为0.53的InGaAs外延材料可与InP衬底完全晶格匹配，能实现性能优良的室温探测器，响应波段0.9-1.7μm。夜天光的能量主要集中在可见-短波红外波段，该波段的微光成像在民用安全和国防领域具有重要意义。国际上，InGaAs探测器的一个重要发展方向是向可见波段拓展，将可见-短波红外集成到一个器件，简化微光成像系统。由于该探测器的应用涉及敏感领域，国外相关研究方法、技术对中国严格禁运，国内尚未见相关研究报道。本项目针对微光成像的光谱范围和低照度特点，提出研究低暗电流的向可见拓展的InGaAs探测器，在具有阻挡层结构的外延材料、低损伤衬底剥离方法、多层增透膜设计及其与探测器片上耦合光谱特性等方面开展研究，建立可见-短波红外宽波段响应的InGaAs探测器的结构设计与工艺新方法，明确暗电流机制并进一步降低器件暗电流。本项目将为实现我国微光成像核心光电器件的自主研发和技术创新奠定基础。

夜天光的能量主要集中在可见-短波红外波段，该波段的微光成像在民用安全和国防领域具有重要意义。国际上，InGaAs探测器的一个重要发展方向是向可见波段拓展，将可见-短波红外集成到一个器件，简化微光成像系统。本项目针对微光成像的光谱范围和低照度特点，研究向可见拓展的宽谱段InGaAs探测器，为我国微光成像核心光电器件提供新的技术途径。项目团队围绕项目目标和研究内容，开展了深入系统的研究，完成了项目究内容，主要研究成果及应用价值如下：.①设计了具有阻挡层结构的InGaAs外延材料，模拟InGaAs器件在可见波段的光电性能，开展了外延材料生长与表征分析。.②建立了低损伤InP衬底剥离工艺方法，开展机械抛光和化学湿法腐蚀工艺研究，并引入ICP-RIE工艺，实现了InP接触层的准确调控。.③开展了多层增透膜的设计仿真，实现了在可见拓展焦平面上的工艺集成，获得了高性能可见-短波红外320×256 InGaAs焦平面探测器。.④实现了可见-短波红外InGaAs面阵探测器组件，并应用于可见-短波红外微型相机，进行了成像演示。. 在性能指标方面，本项目研制的320×256 InGaAs焦平面探测器，光谱响应范围0.4μm~1.7μm，在0.5μm的量子效率达到了43.9%，在0.8μm的量子效率达到了61.6%，在1.5μm的量子效率达到了90.0%，与国际同行的最新报到处于相当的技术水平。. 本项目培养博士研究生两名，发表20篇标注本项目资助的期刊论文，发表8篇标注本项目资助的会议论文，申请8项相关的发明专利，其中5项已授权。