正照射与背照射InGaAs探测器的性能对比研究

首先介绍了InGaAs台面探测器的研究进展,然后为了验证利用台面结制作背照射器件的可行性,利用分子束外延(MBE)方法生长的掺杂InGaAs吸收层PIN InP/InGaAs/InP双异质结外延材料,通过台面制作、钝化、电极生长、背面抛光等工艺,制备了8元台面InGaAs探测器,并测试了正照射和背照射时,器件的Ⅰ-Ⅴ、信号和响应光谱.测试结果表明,正照射和背照射情况下,器件的响应信号差别不大,正照射下器件的平均峰值探测率为4.1×1011 cm·Hz1/2·W-1,背照射下器件的平均峰值探测率为4.0×1011 cm·Hz1/2·W-1,但背照射情况下器件的响应光谱在短波方向有更好的截止.     

正、背照InGaAs探测器的性能对比研究

为了验证利用台面结制作背照射器件的可行性,利用分子束外延(MBE)方法生长的掺杂InGaAs吸收层PIN InP/InGaAs/InP双异质结外延材料,通过台面制作、钝化、电极生长、背面抛光等工艺,制备了8元台面InGaAs探测器,并测试了正照射和背照射时,器件的I-V、信号和响应光谱.测试结果表明,正照射和背照射情况下,器件的响应信号差别不大,正照射下器件的平均峰值探测率为4.13×1011cmHz1/2W-1,背照射下器件的平均峰值探测率为4×1011cmHz1/2W-1,但背照射情况下器件的响应光谱在短波方向有更好的截止.     

正照射与背照射InGaAs探测器的性能对比研究

首先介绍了InGaAs台面探测器的研究进展，然后为了验证利用台面结制作背照射器件的可行性，利用分子束外延（MBE）方法生长的掺杂InGaAs吸收层PIN InP／InGaAs／InP双异质结外延材料，通过台面制作、钝化、电极生长、背面抛光等工艺，制备了8元台面InGaAs探测器，并测试了正照射和背照射时，器件的Ⅰ-Ⅴ、信号和响应光谱。测试结果表明，正照射和背照射情况下，器件的响应信号差别不大，正照射下器件的平均峰值探测率为4．1×10^11cm·Hz^1/2·W^-1，背照射下器件的平均峰值探测率为4．0×10^11cm·Hz^1/2·W^-1，但背照射情况下器件的响应光谱在短波方向有更好的截止。     

256×1线列InGaAs短波红外焦平面的研究

利用分子束外延(MBE)方法生长的掺杂InGaAs吸收层PIN InP/InGaAs/InP双异质结外延材料,通过台面制作、硫化后覆盖聚酰亚胺钝化、电极生长等工艺,制作了台面构造的256×1正照射InGaAs探测器阵列。测试了器件的I-V特性与响应光谱,得出器件的暗电流Id、零偏压电阻R0、G因子;通过信号和噪声的测试,计算出了在278K时的平均峰值探测率为1.33×1012cmHz1/2W-1。256元InGaAs探测器阵列与CTIA结构L128读出电路相互连,经封装后成功制备256×1线列InGaAs短波红外焦平面,在室温(300K)时测得256元响应信号,其响应不均匀性为19.3%。     

128×1线列InGaAs短波红外焦平面的研究

报道了用分子束外延(MBE)方法生长的掺杂InGaAs吸收层PIN InP/InGaAs/InP双异质结外延材料,通过干法刻蚀和湿法腐蚀相结合制作台面、硫化和聚酰亚胺钝化、电极生长等工艺,制备了128×1台面正照射InGaAs探测器阵列.测试了器件的变温I-V、响应光谱和探测率,在278K时平均峰值探测率为1.03×1012cmHz1/2W-1.实现了128元InGaAs探测器阵列与CTIA结构L128读出电路相互连,经封装后,在室温(291K)时成功测出128元响应信号.焦平面响应的不均匀性为18.3%,并对不均匀性产生的原因进行了分析.     

SiNx钝化256元InGaAs短波红外焦平面探测器

为了改善器件的响应均匀性,通过优化台面制作与SiNx钝化工艺制备了高均匀性256元线列正照射InGaAs探测器,实现了该探测器与读出电路的互连,测试了器件的I-V特性、光谱响应、信号和噪声,并利用激光感生电流技术研究了探测器的串音和光敏感区的扩大问题.测试结果表明:在-0.5V偏压下,探测器的暗电流典型值约为0.9nA,平均峰值探测率为7.8×1011cm·Hz1/2·W-1,响应的不均匀性为4.8%.LBIC测试结果表明:光敏元区没有扩大,光敏元之间串音较小,并成功实现了室温扫描成像,图像比较清晰.     

320×256 InAs/GaSb超晶格中/短波双色探测器组件研制

InAs/GaSb超晶格材料制备的新型红外器件在最近十几年得到了迅速发展。文中开展了InAs/GaSb二类超晶格中/短波双色焦平面探测器组件研制,设计了中/短波双色叠层背靠背二极管芯片结构,用分子束外延技术生长出结构完整、表面平整、低缺陷密度的PNP结构超晶格材料,制备出性能优良的320×256双色焦平面探测器组件,对探测器组件进行了测试分析。结果显示,在77 K下中波二极管RA值达到26.0 kΩ·cm2,短波的RA值为562 kΩ·cm2。光谱响应特性表明短波响应波段为1.7~3 μm,中波为3~5 μm,满足设计要求。双色峰值探测率达到中波3.12×1011 cm·Hz1/2W-1,短波1.34×1011 cm·Hz1/2W-1。响应非均匀性中波为9.9%,短波为9.7%。中波有效像元率为98.46%,短波为98.06%。     

256元InGaAs线列红外焦平面及扫描成像

报道了用分子束外延(MBE)方法生长掺杂InGaAs的PIN InP/InGaAs/InP外延材料,通过台面制作、硫化处理、ZnS/聚酰亚胺双层钝化、电极生长等工艺,制备了256元正照射台面InGaAs线列探测器,278K时平均峰值探测率为1.33×1012 cmHz1/2W-1.测试了不同钝化方式探测器典型Ⅰ-Ⅴ曲线和探测率,硫化可以减小探测器暗电流,ZnS/聚酰亚胺双层钝化效果最好.并对ZnS/聚酰亚胺双层钝化InGaAs探测器进行了电子辐照研究.256元InGaAs探测器阵列与两个CTIA结构128读出电路互连并封装,在室温时,焦平面响应率不均匀性为19.3%.成功实现了室温扫描成像,图像比较清晰.     

短波红外InGaAs焦平面探测器研究进展

短波红外InGaAs焦平面探测器具有探测率高、均匀性好等优点,在航天遥感、微光夜视、医疗诊断等领域具有广泛应用。近十年来,中国科学院上海技术物理研究所围绕高灵敏度常规波长（0.9～1.7 μm） InGaAs焦平面、延伸波长（1.0～2.5 μm） InGaAs焦平面以及新型多功能InGaAs探测器取得了良好进展。在常规波长InGaAs焦平面方面,从256×1、512×1元等线列向320×256、640×512、4 000×128、1 280×1 024元等多种规格面阵方面发展,室温暗电流密度优于5 nA/cm2,室温峰值探测率优于5×1012 cm·Hz1/2/W。在延伸波长InGaAs探测器方面,发展了高光谱高帧频1 024×256、1 024×512元焦平面,暗电流密度优于10 nA/cm2和峰值探测率优于5×1011 cm·Hz1/2/W@200 K。在新型多功能InGaAs探测器方面,发展了一种可见近红外响应的InGaAs探测器,通过具有阻挡层结构的新型外延材料和片上集成微纳陷光结构,实现0.4～1.7 μm宽谱段响应,研制的320×256、640×512焦平面组件的量子效率达到40%@0.5 m、80%@0.8 m、90%@1.55 m;发展了片上集成亚波长金属光栅的InGaAs偏振探测器,其在0 °、45 °、90 °、135 °的消光比优于20:1。     

甚长波碲镉汞红外探测器制备研究

报道了碲镉汞甚长波红外焦平面探测器的最新研究进展。采用水平液相外延In掺杂和垂直液相外延Ａs掺杂技术生长了高质量的p on n型双层异质结材料。并通过提高材料质量将双层异质结材料的双晶衍射半峰宽控制在30 arcsec以内。基于台面器件加工、表侧壁钝化以及In柱互连工艺,制备了640×512,25μm碲镉汞甚长波红外焦平面器件。通过进一步优化了材料生长和芯片制备工艺,在65 K的工作温度下,该器件的截止波长为1435 μｍ,有效像元率为9806,平均峰值探测率为809×1010cm·Hz1/2·W-1。     

Field-component statistics of externally illuminated overmodedcavities

The Λ distribution describes the statistical behavior of the measured square of the electric or magnetic field in an externally illuminated overmoded cavity. An approximation of the individual phase-quadrature fields is derived from this distribution. Numerical evaluation of this approximation to the squared phase-quadrature fields convolved with itself shows good agreement (±1% away from the tail of the distribution) with the original Λ distribution. Comparison of theoretically derived cable currents with experimental data exhibits considerably better than factor-of-two correspondence     

Open-circuit voltage of an illuminated nonideal heterojunction

The possibility of using the model of tunneling-recombination transport for calculating the photovoltage of an illuminated nonideal heterojunction is demonstrated. The technique of photoexcitation with light of varying spectral composition is used, and the difference in the behavior of the dependence of the photovoltage on the illumination is explained. The heterojunction photovoltage is calculated taking into account the predominance of the tunneling-recombination transport mechanism in the barrier region and modification of the shape of the potential barrier during illumination. It is shown that the dependences calculated at various illumination levels agree with those obtained experimentally.     

An antenna illuminated by a cavity resonator

A microwave aperture antenna with small phase errors has been constructed by utilizing the plane field configuration inside a box-shaped resonator to directly excite the aperture, which is the same shape as the resonator. The antenna is narrow band, as Q of the resonator should be sufficient for selecting the proper mode in the resonator. The possible bandwidth of the antenna is thus inverse proportional to the desired gain. Reasonable agreement between theory and measurements was obtained.     

Simple parameter extraction method for illuminated solar cells

This paper presents a simple and successful method for evaluating the series resistance, the ideality factor, the saturation current and the shunt conductance in illuminated solar cells. The approach involves the use of an auxiliary function and a computer-fitting routine. The validity of this method has been confirmed by the way of current–voltage measurements of a commercial silicon solar cell, a module and a plastic solar cell.     

Otpically illuminated dielectric interfaces as high-speed far-infrared modulators

A new device for the gigahertz modulation of far-infrared radiation is analytically and numerically analyzed. It consists of a thin layer of a high-mobility, direct-bandgap semiconductor, such as GaAs, in which a high-density electron-hole plasma is rapidly created and destroyed, thereby rapidly changing the free-carrier reflectivity of the active layer. Illumination by a high-power, near-infrared laser diode array generates the plasma through intrinsic photoconduction. It is shown that this device acis primarily as an amplitude modulator, and that its efficiency increases sharply with increasing far-IR frequency, in contrast to a Schottky diode, which acts primarily as a phase modulator, and whose efficiency falls off sharply with far-IR frequency. The breakeven frequency lies at about 1.5 THz, depending slightly on the assumed device parameters. The relative advantage of the new device increases rapidly with increasing far-infrared frequency. At an operating frequency of 2.5 THz (119 μm), for example, a 1 GHz modulation bandwidth may be achieved with a single-sideband conversion loss of only-21 db, versus a Schottky's loss of-39 db, assuming a laser diode power of 1 W, which is readily available from recently developed laser diode arrays.     

硅全耗尽背照式光电二极管的光谱响应

建立了一个预测硅全耗尽背照式光电二极管响应率的解析模型.分析了所加反偏压与光谱响应之间的关系,解出了硅全耗尽背照式光电二极管的响应率和器件各参数之间的关系,并根据选定参数值计算出了给定外加偏压下400～1 100 nm范围的光谱响应曲线,预测探测器光谱响应峰值在1μm,峰值响应率达到0.72 A/W.实测结果表明:器件峰值响应与预测一致,反偏压对响应率的影响与预测相同,即响应率随着反偏压的升高而增大.并且在各种反偏压下的光谱响应曲线形状与预测基本吻合,证明了建立的模型可以正确地预测器件性能.     

Approximation of the carrier generation rate in illuminated silicon

In order to shorten the calculation time for solar cell properties, the light generation rate usually expressed as a sum of individual contributions over the whole solar spectrum is replaced by a curve-fitted approximation. This approximation is represented by a series of three to five exponential terms resulting in an analytical solution of the continuity equation which has the same form as for the actual generation rate. Using the proposed approximation the calculated contribution of the base region to the short-circuit current fits closely the result obtained with the actual generation rate.     

Optical gain and large-signal characteristics of illuminated GaAs MESFET's

The illuminated large-signal characteristics of a uniformly doped epitaxial GaAs MESFET have been measured when optically gated with an He-Ne laser source. The dependence of the measured optical gains on the applied electrical biases and optical intensity, position, and spot size indicate that the dominant dc gain mechanisms are transit time photoconductivity combined with an effective photovoltaic change in the pinchoff voltage. The photovoltaic change in the pinchoff voltage dominates for high optical power levels, while the photoconductive response dominates for low power levels. Optical gains in the range of 5-10 were measured for the photoconductive regime, while gains in the range of 50-70 were measured for the photovoltaic regime.     

Monolithic InGaAs photodiode array illuminated through an integrated waveguide

A linear array of InGaAs PIN photodiodes has been fabricated which can be illuminated through a slab waveguide from the opposite side of the InP substrate via total reflection at a V-groove mirror. Absorption losses in the double-heterostructure waveguide are 2.5 dB/cm. The internal quantum efficiency of the photodiodes, including the mirror loss, is 87%, and an optical crosstalk between the diodes better than ?40 dB was measured.