平面型铟镓砷红外探测器八元线列的制备与性能分析

由于具有高探测率、高可靠性以及可室温工作等特点,InGaAs红外探测器在航天遥感领域具有重要的应用,而平面型的InGaAs红外探测器是国际主流的结构,但是国内这一方面的研究却刚刚起步,文中通过闭管锌扩散方式制备了平面型In0.53Ga0.47As红外探测器八元线列,测试了器件的伏安特性,得到器件的暗电流在零偏压下平均值为6.5pA,-500mV下为18.2pA,并且通过对器件信号、噪声以及响应光谱的测试得到器件的峰值响应率,其平均值为8.11×1011cm·Hz1/2·W-1,不均匀性为4.69%.通过器件的优值因子R0A计算了器件理论峰值响应率,结果表明:理论峰值响应率平均值高于测试值,且不均匀性较大.通过拟合器件的伏安曲线分析了器件峰值响应率与理论值的差别.     

基于铟镓砷材料的新型太赫兹/亚毫米波探测器研究

对一种基于生长在半绝缘InP衬底上InGaAs外延材料的新型太赫兹室温探测器进行研究。首先在HFSS理论计算的基础上对器件天线阻抗、驻波比、辐射方向图等特性参数进行分析。其次,通过光刻、腐蚀、溅射、点焊等工艺制作出对称金属电极天线耦合的太赫兹探测器件。结合自己搭建的0.037 5 THz器件响应测试系统,得到铟镓砷太赫兹探测器件在不同偏置电流和不同调制频率下的器件响应曲线。结果表明器件具有明显的光电信号和快的响应速度。通过利用高莱探测器进行标定,得到器件在0.037 5 THz时的电压灵敏度优于6 V/W,器件噪声等效功率NEP优于1.610-9 W/Hz1/2,器件响应时间优于300 s。     

线列探测器的冷屏设计

本文报告冷却的屏蔽罩遮光效应的计算结果,给出了在有矩形冷却小孔的线列探测器中,在不同的视场角下,遮光效应与小孔长/宽比的函数关系。     

线列探测器的冷屏设计(Ⅱ)

本文报导线列探测器中椭圆形小孔冷却屏蔽的退光效应的计算结果。计算时小孔的长轴/短轴比是可变的。结果表明,椭圆形小孔比矩形小孔的设计更好。     

In0.53Ga0.47As/InP红外探测器材料与线列器件

采用LPMOCVD技术生长了In0.53Ga0.47As红外探测器器件结构材料,其晶格失配为2.19×10-4.利用锌扩散制备探测器单元和1×256线列器件,光谱响应范围为O.90～1.70 μm,量子效率为73%,在零偏压下,暗电流为1.62×10-8A,动态零压电阻为2.72×105Ω.单元探测器波段探测率为1.71×1012cmHz1/2W-1.     

基于锌扩散的InGaAs/InP平面型红外探测器快速热退火研究

系统研究了快速热退火对锌扩散的In_0.53Ga_0.47As/InP PIN探测器的影响。利用电化学电容电压和二次离子质谱技术分析了退火前后Zn和净受主的浓度分布,结果表明退火过程会影响杂质浓度,但不影响扩散深度。制备了不同退火条件的In_0.53Ga_0.47As/InP PIN探测器。器件测试反映,未退火的探测器在260~300K具有更低的器件电容和更高的激活能。通过暗电流成分拟合对器件暗电流机制进行分析,未退火器件表现出更低的肖克利-里德-霍尔产生复合电流和扩散电流,因而室温下未退火器件具有更高的峰值探测率。为了制备高性能低掺杂吸收层结构的平面型InGaAs探测器,快速热退火是不必要的工艺。     

可见增强的32×32元平面型InGaAs/InP面阵探测器

为了实现In Ga As探测器响应波段向可见增强,在传统的外延材料中加入一层In Ga As腐蚀阻挡层,制备了32×32元平面型In Ga As面阵探测器,采用机械抛光和化学湿法腐蚀相结合的方法,去除了In P衬底.结果表明,探测器的响应波段为0.5~1.7μm,室温下在波长为500 nm处的量子效率约为16%,850 nm处量子效率约为54%,1 550 nm处量子效率约为91%.暗电流大小与衬底减薄之前基本保持一致.理论分析了材料参数对器件量子效率的影响,为进一步优化可见波段探测器的量子效率提供了依据.     

线列探测器实时非均匀校正技术研究

目前线列探测器仍在一些重大工程项目中广泛应用,且多采用两点定标法实现非均匀性的校正.两点定标法需要不断定标以更新校正系数.为了研究能够实现实时校正的方法,主要针对线列探测器的非均匀性特点,对目前几种简单的自适应非均匀校正算法进行分析,并给出了VC6.0++中对MODIS数据的仿真结果.实验表明,恒定统计量算法中参数的选择很难确定,神经网络算法并不适于线列探测器的非均匀校正,重点分析了SPRITE热像仪所采用的归一法,并对其加以改进,使硬件实现更简单、快速.最后,给出了一种采用DSP和CPLD的硬件实现方案,可以完成线列探测器的实时非均匀校正.     

基于线列红外探测器的图像增强算法研究

针对线列红外探测器扫描成像特点,提出了一种基于平台直方图统计的红外图像增强算法。仿真结果表明,该算法能够校正扫描型热像仪由盲、闪元引起的黑白道,提高图像的对比度,修正全局灰度等级,锐化图像中的边缘细节,对扫描成像系统的红外图像具有较好的增强效果。     

线列热释电探测器的热串音

本文首先建立了线列热释电探测器的三维数理模型。应用热传导理论,求得器件中温升分布的解析解,进而分析了影响线列热释电探测器热串音的几个因素,提出了降低热串音的主要措施。     

Transferred-electron oscillations in In0.53Ga0.47As

Transferred-electron oscillations were observed and investigated in planar devices of In0.53Ga0.47As. The peak-to-peak magnitude of oscillations with respect to the device current at threshold field was as high as 70%, indicating the peak-to-valley velocity ratio of 3.3:1 for this material. The domain velocity was estimated from the oscillation frequency (2 GHz) and the corresponding device length (40 ?m) to be 8×106 cms?1. The results presented in the letter show a promising prospect for TED applications of this ternary alloy.     

Transferred-electron effect in In0.53Ga0.47As

The transferred-electron effect in In0.53Ga0.47As is demonstrated by observation for the first time in the travelling-domain mode. Current pulses of more than 70% are found. From velocity/field characteristics the peak velocity is determined as (2.2 ± 0.3) × 107 cm/s. The temperature dependence of the peak current is measured.     

Metal-semiconductor-metal photodetector on p-type In/sub 0.53/Ga/sub 0.47/As

An MSM Schottky barrier photodetector based on p-type In/sub 0.53/Ga/sub 0.47/As suitable for detection in the 0.8-1.7 wavelength range is reported. Aluminium metallisation was used. The large area devices exhibited responsivity of about 0.4 A/W at 1.3 mu m and tau /sub on/>     

Dark noise of Ga0.47 In0.53As photoconductive detectors

We have studied the dark noise of planar, interdigitated Ga0.47In0.53As photoconductive detectors by measuring the statistical distribution of the dark current under DC bias. The measurements reveal two interesting results: (i) the probability distribution of the dark current around its DC level is Gaussian and (ii) the standard deviation of the probability distribution grows exponentially with increasing bias voltage. Utilising these data an optimum bias level was calculated to maximise the receiver sensitivity of the detector.     

Longitudinal photoeffect in In0.53Ga0.47As p-n junctions

A longitudinal photoeffect in In_0.53Ga_0.47As p-n junctions was investigated: the dependence of the longitudinal photoemf V _{ph 1} on the coordinates of the light spot, the temperature, and the magnetic field. The dependences on the coordinates of the light spot were found to be linear; the theoretical values of V _{ph 1} agree with the experimental values. The temperature variation of V _{ph 1} in the interval 100–300 K is explained by the variation of the current-carrier mobility as a result of thermal scattering by the lattice. In a magnetic field, V _{ph 1} is observed to increase as a result of the photomagnetic effect. Fiz. Tekh. Poluprovodn. 31, 864–865 (July 1997)     

High-gain In0.53Ga0.47As:Fe photoconductive detectors

Photoconductive detectors were fabricated on semi-insulating liquid phase epitaxial In0.53Ga0.47As/InP doped with Fe for the first time. Their performance characteristics have been compared with identical devices made from Zn-doped p-In0.53Ga0.47As/InP. Internal optical gains up to 10 were measured in the Fe-doped devices. The bias and intensity-dependent gain characteristics of these devices are discussed.     

Current instabilities in Ga0.47In0.53As transferred-electron devices

Time-resolved measurements of the device current in Ga0.47In0.53As transferred-electron devices are presented. The current drop, usually attributed to domain nucleation shows an unexpected behaviour because a drop of the device current of up to 90% is observed. This cannot be explained solely by the model of domain formation caused by electron transfer. The influence of transport properties of the central valley is discussed, giving rise to the assumption of its dominant effect on domain nucleation.     

一种应用于太赫兹频段的平面In0.53Ga0.47As耿氏二极管

介绍了一种InP衬底上的平面In0.53Ga0.47As耿氏二极管的设计、制作和测试方法。为了提高器件的输出功率,使用Advanced Design System 2011仿真软件设计了50 ?共面波导馈电结构作为器件电极,减少测试功率损耗;同时在版图设计时加大了金属电极面积,改善器件的散热效果。测试结果表明,当所加电压为4.4 V时,沟道长度和宽度分别为2 μm和120 μm器件的基波振荡频率为168.3 GHz,输出功率为-5.21 dBm。这种高功率平面结构耿氏二极管在太赫兹频段具有巨大的应用潜力。