锑化物超晶格红外探测器研究

发布时间：2018-05-03 02:00

本文选题：锑化物超晶格 + 红外探测器　；参考：《中国科学院上海技术物理研究所》2017年博士论文

【摘要】：锑化物超晶格红外探测器是当前光子型红外探测器领域的研究热点,是极具潜力的新型红外技术。锑化物超晶格探测器以III-V族化合物半导体为材料,利用高精度材料生长技术,控制不同材料构成特性的结构,以实现红外辐射的探测。通过改变结构中各层材料的厚度来调整探测器的禁带宽度,探测范围可覆盖1μm至30μm。III-V族化合物半导体材料生长和器件制备技术成熟,均匀性好,此外还具有抗辐照性能强等优势,所以锑化物超晶格探测器受到了广泛的研究。本文聚焦于InP基的In GaAs/GaAsSb和GaSb基的InAs/GaSb两种锑化物II类超晶格红外探测器,主要开展了以下几方面的研究:1.研究了InP衬底上GaAsSb材料的生长工艺,利用非平衡热力学模型对生长过程进行了模拟,在此基础上获得了In GaAs/GaAsSb II类超晶格材料。利用光致发光谱对该材料的光学性质进行了研究,发现由于能带的弯曲效应,造成PL峰值能量值随着激发功率的增加出现蓝移的现象,并对峰值能量与温度关系进行了拟合。研究了Be掺杂温度对超晶格特性的影响,并通过Be的补偿掺杂获得了p型的InGaAs/GaAsSb II类超晶格。制备了不同吸收区厚度和吸收区补偿掺杂的探测器,并对性能进行了表征,发现吸收区厚度的增加对提升器件量子效率有限,而采用补偿掺杂技术的探测器量子效率得到了显著提升。最后制备出了InGaAs/GaAsSb II类超晶格320×256焦平面原型器件,在200 K温度下,pπn焦平面器件的峰值探测率为4.3×1011 cm?Hz1/2?W-1,响应不均匀性12%。2.设计了和生长了GaSb基pBπBn结构InAs/GaSb II类超晶格材料,吸收区的晶格失配Δa/a仅为2.1×10-5,-1级卫星峰的全宽半高峰(FWHM)为21.6弧秒。为了获得高性能的长波12μm InAs/GaSb II类超晶格焦平面器件,针对GaSb衬底强吸收红外光的问题,对所用GaSb衬底对红外光的吸收机制和衬底厚度与透射率的关系进行了研究,发现GaSb衬底的吸收机制以光学声子和电离杂质散射为主导,衬底减薄对GaSb透过率的提升十分有限。通过选择性腐蚀试验得到了超晶格探测器的去衬底工艺,解决了衬底对红外光的强吸收问题。针对大面阵焦平面器件热失配导致的裂片问题,对焦平面器件封装结构进行优化设计和实验验证,提出了最优的封装方案,成功获得了320×256长波12μm InAs/GaSb II类超晶格焦平面器件。3.对制备的320×256长波12μm InAs/GaSb II类超晶格焦平面器件进行性能测试和分析。80 K和65 K温度下探测器的相对响应光谱基本重合,50%截止波长为12μm。通过四种暗电流机制对探测器的拟合进行了拟合与分析,当温度高于70 K时,暗电流以扩散电流为主导,低温时以产生复合电流为主导。测试了不同背景辐射下探测器的电流-电压曲线,发现探测器的响应并不会随着温度与偏压发生变化。研究了温度和电路偏置电压与焦平面器件响应之间的关系,得到了电路注入效率是主要影响焦平面器件响应的因素。对盲元产生的缘由进行了分析,发现少部分为铟柱互连不佳,大部分是由于探测器的暗电流比平均值偏大。通过反馈优化器件的制备工艺,获得了国内第一个长波12μm InAs/GaSb II类超晶格焦平面组件,峰值探测率能够达到7.2×1010 cm?Hz1/2?W-1,盲元率为2.7%,响应不均匀性为7.8%,噪声等效温差29.2 mK。4.针对红外遥感的应用,开展了γ辐照对InAs/GaSb II类超晶格探测器性能影响的研究。通过背照型器件的实时辐照实验,InAs/GaSb II类超晶格器件性能基本未发生变化,表明该超晶格探测器具有良好的抗辐照特性。结合实时的电流-电压曲线和辐照停止后器件电流随时间的演化情况,对辐照所带来的微观损失机理进行了分析,发现零偏和小反偏压下,电离效应损伤为主导,短时间即可恢复,大反偏压下则以位移效应损伤为主导,恢复时间明显增长。对焦平面器件辐照前后的性能测试进行对比,发现辐照并不会影响探测器的基本性能,但会影响读出电路,使其工作状态发生变化甚至是失效。通过将正照型器件的辐照实验结果与背照型器件对比,发现二者具有相同的辐照损伤机制。
[Abstract]:Antimony Superlattice Infrared detector is a hot spot in the field of current photon infrared detectors. It is a potential new infrared technology. Antimony superlattice detector uses III-V compound semiconductor as the material, and uses high precision material growth technology to control the structure of different material components, so as to realize the detection of infrared radiation. The width of the detector is adjusted by changing the thickness of the material in the structure. The detection range can cover the growth of 1 to 30 m to 30 mu semiconductor materials and the mature of device preparation technology, good uniformity and strong radiation resistance. So the antimony superlattice detector has been widely studied. This paper focuses on the focus of this paper. InP based In GaAs/GaAsSb and GaSb based InAs/GaSb two antimony II Superlattice Infrared detectors have been studied in the following aspects: 1. the growth process of GaAsSb materials on the InP substrate was studied. The growth process was simulated by the non equilibrium thermodynamic model, and the In GaAs/GaAsSb II superlattice was obtained on this basis. The optical properties of the material were studied by photoluminescence. It was found that the peak energy value of PL appeared blue shift with the increase of the excitation power, and the relationship between the peak energy and the temperature was fitted. The effect of the Be doping temperature on the properties of the superlattice was studied, and the compensation of the Be was studied. The P type InGaAs/GaAsSb II superlattice is obtained by doping. The detector with different absorption region thickness and absorption region is prepared, and the performance is characterized. It is found that the increase of the thickness of the absorption region is limited to the quantum efficiency of the hoisting device, and the quantum efficiency of the detector using the compensation doping technique has been greatly improved. Finally, the preparation of the detector is made. The InGaAs/GaAsSb II superlattice 320 x 256 focal plane prototype device, at the temperature of 200 K, the peak detection rate of P PI n focal plane is 4.3 x 1011 cm? Hz1/2? W-1, and the response inhomogeneity 12%.2. design and growth of GaSb based pB PI Bn structure superlattice materials, the lattice mismatch of the absorption region is only 2.1 x 10-5, the peak satellite peak The full width and half peak (FWHM) is 21.6 arc seconds. In order to obtain high performance long wave 12 m InAs/GaSb II superlattice FPA, the absorption mechanism of infrared light on the GaSb substrate and the relationship between the thickness of the substrate and the transmittance of the substrate on the GaSb substrate are studied. The absorption mechanism of the GaSb substrate is found to be optical phonon. With the ionizing impurity scattering as the dominant factor, the enhancement of the GaSb transmittance is very limited by substrate thinning. Through selective corrosion test, the undersubstrate process of the superlattice detector has been obtained. The strong absorption of the substrate to the infrared light is solved. The packaging structure of the focal plane device is carried out for the split sheet problem caused by the thermal mismatch of the large surface array focal plane devices. Optimized design and experimental verification, the optimal package scheme was proposed. The performance test of the 320 * 256 long wave 12 m InAs/GaSb II superlattice FPA with 320 * 256 long wave 12 mu m InAs/GaSb II superlattice device was successfully obtained and the analysis of the relative response spectrum of the detector under.80 K and 65 K temperature was the basic coincidence, 5 0% the cut-off wavelength is 12 mu m. to fit and analyze the fitting of the detector through four dark current mechanisms. When the temperature is higher than 70 K, the dark current is dominated by the diffusion current, and the composite current is produced at low temperature. The current voltage curve of the detector under different background radiation is tested, and the response of the detector is not found to be with the temperature. The relationship between the temperature and the circuit bias voltage and the response of the focal plane is studied. It is found that the injection efficiency of the circuit is the main factor affecting the response of the focal plane device. The cause of the blind element is analyzed, and it is found that a few indium interconnects are poor, most of which are due to the average dark current ratio of the detector. The first long wave 12 m InAs/GaSb II superlattice FPA module is obtained by feedback optimization, the peak detection rate can reach 7.2 x 1010 cm? Hz1/2? W-1, the blind element rate is 2.7%, the response inhomogeneity is 7.8%, the noise equivalent temperature difference 29.2 mK.4. is applied to the infrared remote sensing, and InAs is carried out to InAs Research on the performance of /GaSb II superlattice detectors. The performance of InAs/GaSb II superlattice is basically unchanged through real-time irradiation experiments of a backlit device. It shows that the superlattice detector has good radiation resistance. The microscopic loss mechanism caused by irradiation is analyzed. It is found that the damage of ionization effect is dominant under the zero bias and the small reverse bias, and the time can be restored in a short time. The displacement effect is dominant and the recovery time is obviously increased under the large reverse bias. The comparison of the performance test before and after the irradiation of the focal plane device shows that the irradiation does not affect the exploration. The basic performance of the tester will affect the read-out circuit and make its working state change or even fail. By comparing the experimental results of the irradiated device to the backlit device, the two are found to have the same radiation damage mechanism.

【学位授予单位】：中国科学院上海技术物理研究所
【学位级别】：博士
【学位授予年份】：2017
【分类号】：TN215

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