红外-近红外波长变换器件p-QWIP-LED研究

报道了一种基于p型量子阱红外探测器(QWIP)和发光二极管(LED)的新型量子阱红外探测器. 该器件作为一种p型量子阱红外探测器(QWIP)和发光二极管(LED)的有效集成器件, 可以将QWIP探测的长波红外信号经光电转换过程后变成LED在近红外的发光. 通过电学直接读出方式和近红外(0.87 μm)光强度变化读出方式, 从实验上测量了器件的红外响应光谱, 设计与制备的器件实现了从长波红外(7.5 μm)向近红外(0.87 μm)的波长变化. 研究结果表明这种红外-近红外波长变换途径有可能导致红外焦平面技术体制的变化.     

甚长波量子阱红外探测器的暗电流特性研究

基于载流子在量子结构中的输运理论研究了甚长波量子阱红外探测器(峰值响应波长15μm，量子阱个数大于40)的载流子的输运性质.研究结果表明，在甚长波量子阱红外探测器中，电流密度一般很低，暗电流主要来源于能量高于势垒边的热激发电子.通过薛定谔方程和泊松方程以及电流的连续性方程的自洽求解，发现外加偏压下电子浓度在甚长波器件各量子阱的分布发生较大变化，电场在整个器件结构上呈非均匀分布，靠近发射极层的势垒承担的电压远远高于均匀分布的情形.平带模型假定电压在器件体系上均匀分布，导致小偏压下的理论计算值远远低于实验值. 关键词： 甚长波量子阱红外探测器 量子波输运 暗电流     

用金属小球进行长波量子阱红外探测器的光耦合

针对实验中9.5μm峰值响应波长的n型长波量子阱红外探测器设计运用二维金属小球(铜)阵列作光耦合结构.金属小球阵列均匀填充在绝缘的胶黏剂中，基于惠更斯原理研究二维金属小球阵列体系的光耦合和光吸收，结果表明对9.5μm响应波长的长波量子阱红外探测器，采用周期为3μm，半径为0.9μm左右的金属小球阵列可以获得最佳的光耦合.优化设计后的量子效率(66%)远高于45°磨角耦合的量子效率(38%)，为实验运用金属小球阵列进行长波量子阱红外探测器的光耦合提供了基本的理论依据和详细的优化设计方案.     

Detection Wavelength of Strained InxGa1-x As/GaAs Very-Long-Wavelength Quantum Well Infrared Photodetectors

Detection wavelength is one of the key performance indices of infrared photodetectors. We study the character of detection wavelength of the strained InxGa1-xAs/GaAs very-long-wavelength （〉 12 μm） quantum well infrared photodetectors （VLW-QWIPs） characterized by the photoluminescence （PL） and photocurrent （PC） measurements. Based on the theoretical calculation and experimental data, we have built a practical model for the Inx Ga1-xAs/GaAs strained VLW-QWIPs, from which the interband transitions, intersubband transition and peak detection wavelength can be determined. Afterwards, the dependences of detection wavelength and device operation mode on the In mole fraction and InxGa1-xAs well width are presented, which will be helpful for device design and optimization.     

256×1甚长波多量子阱红外焦平面线列研制

通过材料设计与制备,甚长波GaAs／AlGaAs多量子阱红外探测器的峰值响应波长14．6μm,响应带宽大于2．2μm．256×1焦平面线列采用垂直入射二维光栅耦合工作模式,45K温度下,单元响应率4．28×10^-2A／W、单元黑体探测率Db＊=5．14×10^9cm．Hz^1.2/W、单元黑体单色探测率Dλ＊=4．24×10^10cm．Hz^1/2/W．通过铟柱与互补式金属一氧化物一半导体读出电路互连得到的甚长波量子阱红外探测器FPA（focal planearray）在积分时间100μs时,有效像元率Nef=99．22％、平均响应率R=3．485×10^6V/W、响应率的不均匀性UR=5．83％、平均黑体探测率典型值Db^＊=2．181×10^8cm．Hz^1/2/w、平均单色探测率Dλ^＊=8．288×10^9cm．Hz^1/2/W．器件已适合进行室温目标的热像图．     

红外光电子学中的新族——量子阱红外探测器

回顾了近10年基于半导体中量子限制效应红外探测器的进展．主要关注的是二维限制结构,即量子阱结构,形成的区别与传统红外光子探测的子带跃迁机理．在红外光电子领域作为新族的量子阱红外探测器（quantum well infrared photo-detector,QWIP）与最典型的红外探测器代表碲镉汞红外探测器进行了各自特色的分析,包括基本工作机理和材料与器件的制备技术等方面．对于QWIP发展的回顾提升了与碲镉汞红外探测器之间的互补关系．也给出了对于QWIP在未来发展方面的基本趋势．     

Photoluminescent properties of di(8-hydroxyquinolato) zinc impregnated in nanoporous glass

Photoluminescent properties of a metal-organic complex, di(8-hydroxyquinolato) zinc, impregnated in nanoporous glass were investigated. In comparison with those in the normal organic fluorescent material, the emission band of the impregnated organic phosphor became wider. Blueshift (14 nm) was observed due to π*→n emission transition. The excitation band of the embedded organic phosphor had a larger blueshift and was divided into several sub-bands. The intensity in the short wavelength end of the embedded organic fluorescent material became much stronger.     

Photoluminescent properties of di(8-hydroxyquinolato) zinc impregnated in nanoporous glass

Photoluminescent properties of a metal-organic complex, di(8-hydroxyquinolato) zinc, impregnated in nanoporous glass were investigated. In comparison with those in the normal organic fluorescent material,the emission band of the impregnated organic phosphor became wider. Blueshift (14 nm) was observed due to π* → n emission transition. The excitation band of the embedded organic phosphor had a larger blueshift and was divided into several sub-bands. The intensity in the short wavelength end of the embedded organic fluorescent material became much stronger.     

A New Resonant Tunnelling Structure of Integrated InGaAs/GaAs Very-Long-Wavelength Quantum-Well Infrared Photodetector

We perform a theoretical study on a low dark current InGaAs/GaAs very-long-wavelength （〉 12 μm） quantum well infrared photodetector （VLW-QWIP）, based on a double barrier resonant tunnelling structure （DBRTS）. The ground tunnelling state of the central quantum well （QW） of the DBRTS can resonate with the first excited bound state of the doped InGaAs QW by adjusting the structure parameters of the DBRTS. Investigation of the carrier transport performance of this device is carried out based on quantum wave transport theory. It has been shown that the dark current in this device can be significantly reduced by two orders compared to conventional InGaAs/GaAs VLW-QWIPs, while the photocurrent is almost the same as those in conventional VLW-QWIPs. This DBRTS integrated VLW-QWIP structure may stimulate the experimental investigation for VLW-QWIPs at high operation temperatures.     

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