InGaAs焦平面探测器电串音性能的研究

串音与焦平面阵列(FPA)的灵敏度和分辨率密切相关。用模拟的方法定量地计算了In0.53Ga0.47As/InP 探测器焦平面阵列的电串音随光波波长、入射方向和台面的刻蚀深度的变化情况。结果显示：台面结构的器件的串音抑制性能比平面结构的要好;由于材料吸收深度和异质结耗尽层宽度的影响,短波长的光的串音比长波长要小,正照射的串音比背照射要小;另外,当台面的刻蚀深度穿透吸收层厚度时,其电串扰几乎完全被抑制。研究结果提出了相应的InGaAs FPA的低串音设计。     

平面型铟镓砷线列探测器的制备及伏安特性研究

通过闭管锌扩散制备了256元平面型铟镓砷(In0.53Ga0.47As)线列探测器,室温下焦平面平均峰值探测率为5.79×1011cmHz1/2W-1,不均匀性为31%,平均峰值响应率为0.33 A/W.并且通过拟合其伏安曲线得到了器件的理想因子和串联电阻,基于这两个相互独立的参数可以对器件不同区域的性质加以考查,结果表明器件材料具有较好的均匀性,而器件的欧姆接触电阻偏大,且不均匀性达到39%,为工艺的改进提供了重要依据.     

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。     

可见光拓展InP/InGaAs宽光谱红外探测器

由于标准InP/In0.53Ga0.47As短波红外探测器的响应波段为0.87~1.7 m,在高性能夜视中具有重要的应用。为了进一步利用夜天光在可见光区间的辐射能量,需要将InP/In0.53Ga0.47As短波探测器的光谱响应拓展到可见光,从而实现包含可见光和短波波段的宽光谱探测。通过特殊的材料设计和背减薄工艺,成功研制了可见光拓展的320256 InP/InGaAs宽光谱红外探测器。采用增加滤光片的方法完成了器件在可见光、短波的成像演示,结果表明:目标在可见光、短波波段呈现出不同的特征信息,而不加滤光片的可见光拓展InP/InGaAs宽光谱红外探测器则探测到两个波段的信息,既包含目标的可见光信息同时也具有短波信息,从而实现了可见/短波双波段探测的效果,可显著提升对目标的探测能力。     

平面型24元InGaAs短波红外探测器

设计了带有保护环结构的平面型24×1 InGaAs线列短波红外探测器,利用n-i-n+型InP/Ino.53Gao.47As/InP外延材料闭管扩散制备了平面型探测器.LBIC测试显示光敏元没有明显扩大,保护环起到了有效的隔离效果;I-V测试表明器件的优值因子R0A约4.2×106Ω·cm2,在-0.1 V反向偏压下的暗电流密度约22 nA/cm2,拟合得到的理想因子接近1,说明正向电流成分主要为扩散电流;在室温20℃,器件的响应光谱在0.9～1.68 tm波段范围,其平均峰值电流响应率为1.24 A/W,平均峰值探测率为3.0×1012 cm·Hz1/2/W,量子效率接近95％,响应的不均匀性为2.63％.     

平面型GaN p-n结探测器的制备与性能

采用金属有机物化学气相沉积(MOCVD)方法在蓝宝石衬底上制备了p-GaN单晶薄膜.高温(＞1100℃)处理及未处理样品的双晶摇摆曲线测试表明高于1150℃会使材料的晶体质量明显变差,这为平面型紫外探测器制备中的部分注入激活条件提供了选择依据.通过TRIM软件优化了注入条件,在选择性注入改型材料上成功制备了平面GaN ...     

320×256元InAs/GaSb Ⅱ类超晶格长波红外焦平面探测器

报道了320×256元In As/Ga SbⅡ类超晶格长波红外焦平面阵列探测器的研制和性能测试.采用分子束外延技术在Ga Sb衬底上生长超晶格材料,器件采用PBIN结构,红外吸收区结构为14 ML(In As)/7 ML(Ga Sb),焦平面阵列光敏元尺寸为27μm×27μm,中心距为30μm,通过刻蚀形成台面、侧边钝化和金属接触电极生长,以及与读出电路互连等工艺,得到了320×256面阵长波焦平面探测器.在77 K温度下测试,焦平面器件的100%截止波长为10.5μm,峰值探测率为8.41×109cm Hz1/2W-1,盲元率为2.6%,不均匀性为6.2%,采用该超晶格焦平面器件得到了较为清晰的演示性室温目标红外热成像.     

新型Sb基二类超晶格红外探测器

InAs/Ga(In)SbⅡ类超晶格材料由于特殊的二型能带结构,可以通过人造低维结构获得类似于体材料的带间吸收,从而获得较高的量子效率;另外,通过调节材料参数调节能带结构,器件响应波段可调;通过能带结构设计抑制俄歇复合,获得较小的暗电流和较高的器件性能。因为以上特有的材料性能和器件特性,Sb基二类超晶格在国际上被认为是第三代红外焦平面探测器的优选材料。对二类超晶格材料的设计和器件特性进行了研究,设计了峰值波长4μm的nBn结构的中波红外探测器,在没有蒸镀抗反膜的条件下,77 K温度下测试得到的峰值探测率为2.4×1011cm Hz1/2W-1,计算得到的量子效率为47.8%,峰值探测率已经接近目前的碲镉汞中波红外探测器器件性能。研究结果充分显示了二类超晶格优越的材料和器件性能。     

红外探测器探测率的研究与分析

在介绍了红外探测器的组成与工作原理的基础上,分析了红外焦平面探测器的噪声等效功率、探测率对空间红外遥感器成像性能的影响,对红外焦平面探测器探测率的影响因素进行了深入研究。通过理论分析,探测率测量值受测试条件影响,积分时间、辐射源温度、背景辐射和1/f噪声等因素对探测器探测率的测试结果都有一定的影响。     

基于VO_x薄膜8元线列非致冷微测辐射热红外探测器的制备

报道了应用反应离子束溅射以及后退火工艺在石英玻璃以及Si(10 0)衬底上淀积混合相 VOx 多晶薄膜,并且在石英衬底上制备了实验用 8元线列红外探测器。用扫描电镜(SEM)和X射线衍射仪(XRD)分别测试结果显示薄膜为表面光滑、致密且具有针状晶粒的混合相多晶结构,探测器的性能测试结果显示该探测器可以实现 8～ 12μm的非致冷室温红外探测     

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.     

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.     

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.     

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.     

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.     

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)     

Band-to-band tunnelling current in Ga0.47 In0.53 As p-n junctions

The tunnelling current in Ga0.47In0.53As p-n junctions from Zener tunnelling is calculated from the Kane model with no adjustable parameters. This calculation indicates that band-to-band tunnelling becomes an important contribution to the reverse current near breakdown (JR = 10?1 Acm?2) in abrupt p-n junctions for |ND?NA|>6 × 1015 cm?3. Experimental measurements show, however, that band-to-band tunnelling becomes the dominant contribution to the dark current near breakdown for |ND?NA|>4 × 1016 cm?3.