InAs/InAsSb超晶格红外中/中波双色焦平面探测器研制

超晶格材料已经成为了第三代红外焦平面探测器的优选材料。双波段红外探测器能够通过对比两个波段内的光谱信息差异,对复杂的背景进行抑制,提高探测效果,在需求中尤为重要。本文开展了InAs/InAsSb超晶格中/中双色焦平面探测器设计及制备技术研究,从器件设计、材料外延、芯片加工等方面展开研究,制备了中心距30 μm的320×256 InAs/InAsSb二类超晶格中/中波双色焦平面探测器。器件短中波峰值探测率达到7.2×10¹¹ cm·Hz^1/2W^-1,中波峰值探测率为6.7×10¹¹ cm·Hz^1/2W^-1,短中波有效像元率为99.51%,中波为99.13%,获得了高质量的成像效果,实现中中双色探测。     

用于中波红外探测的InAsP/InAsSb超晶格的MOCVD生长和表征

提出了采用金属有机化学气相沉积（MOCVD）生长无Ga且应力平衡的InAsP/InAsSb超晶格，并探索了其作为红外吸收材料的可行性。首先采用k·p理论计算了InAsP/InAsSb超晶格的带隙，发现其波长调节范围可以从中波红外到长波红外。然后通过MOCVD技术在InAs衬底上生长了InAs_0.8P_0.2/InAs_0.7Sb_0.3超晶格。XRD测试结果表明，InAs衬底峰与超晶格零级卫星峰的失配仅61"，即基本实现应力平衡；AFM测试材料表面形貌显示5 μm×5 μm范围内均方根粗糙度为0.4 nm；低温PL光谱显示较强的发光，峰位于3.3 μm的中波红外波段，接近设计值。这些结果表明采用MOCVD生长应力平衡的InAsP/InAsSb超晶格作为红外探测材料具有较好的可行性和实用性。     

IInN0.01Sb0.99薄膜的红外反射光谱及探测特性和退火的影响

对基于GaAs失配衬底的新型红外探测材料InN0.01Sb0.99薄膜的远红外反射光谱, 以及制备成光电导器件后的黑体响应和光电流谱进行了测试, 获得了80 K温度下, 响应峰值约为4.4 μm、半高宽约为3.5 μm、截止波长约为5.7 μm的中波宽带响应红外探测原型器件.研究了退火对InN0.01Sb0.99薄膜光电导器件性能的影响, 发现退火能够改善晶体质量, 提高器件的响应能力, 并减小Moss-Burstein效应的影响.     

非制冷红外探测器用VOx薄膜的制备

介绍了一种采用反应溅射工艺,通过控制不同气氛的分布制备VOx薄膜的方法,并制备出电阻温度系数（TCR）优于－2％的非制冷红外探测器用VOx薄膜。其XPS、XRD分析结果表明,薄膜的生长情况与制备工艺条件有密切关系。     

晶格失配对InAs基室温中波红外探测器性能的影响

采用液相外延技术生长了InAs基室温红外探测器件材料,通过光学显微镜、扫描电子显微镜、X射线衍射仪分析了外延材料表面形貌、截面形貌与晶格失配的关系。分析发现,不恰当的晶体晶格常数匹配度会导致材料表面形貌变差,降低材料的结晶质量,晶格失配在0.22%左右的InAs基外延材料表面形貌较好,缺陷少,晶体质量较好。在此基础上,成功制备出室温探测率D^*为6.8×10⁹ cm·Hz^1/2·W^-1的InAs基室温中波红外探测器,这一性能与国际上红外探测器领军企业美国Teledyne Judson Technologies和日本滨松株式会社的商用InAs基红外探测器性能处于同等水平。     

Ⅱ型超晶格InAs/GaInSb红外探测材料

综述了近年来对InAs/GaInSb Ⅱ型超晶格材料的研究结果,给出了禁带宽度与各层厚度和组分的关系.InAs/GaInSb Ⅱ型超晶格材料对应的工作波长范围在3～25μm,有望在LWIR和VLWIR方面替代HgCdTe.     

势垒型InAs/InAsSb II类超晶格红外探测器研究进展（特邀）

红外探测技术在卫星侦察、军事制导、天文观测、医疗检测、现代通信等重要领域发挥着关键作用。II类超晶格（T2SLs）红外探测器作为继碲镉汞探测器之后的新一代红外探测材料,在稳定性、可制造性和成本等方面具有独特优势。势垒型InAs/InAsSb T2SLs红外探测器是最具潜力的T2SLs红外探测器之一,近年来其关键性能得到了稳步提高,但仍受吸收系数低、异质外延生长困难和暗电流大等因素的制约。文中综述了III-V族T2SLs的发展历程,分析了势垒型InAs/InAsSb T2SLs红外探测器的不同势垒结构、关键性能和发展趋势,指出了势垒型InAs/InAsSb T2SLs红外探测器需要解决的关键问题和未来发展方向。     

InAs/GaSbⅡ类超晶格红外探测技术

由于Ⅱ类超晶格探测器在红外成像探测技术上极大的应用价值和前景,对这一低维半导体结构的研究持续不衰.近年来,Ⅱ类超晶格探测器在国际上发展极为迅速,已经实现了高性能的中波和长波超晶格焦平面探测器并进行了成像试验.改变超晶格的周期,它的吸收截止波长可覆盖3～30μm的宽广范围.由于现代分子束外延材料生长技术,可以在单原子层的...     

GdBa2Cu3O7薄膜红外探测器的研究

本文对红外探测器进行理论分析的基础上，设计并研制了液氮温度下的ＧｄＢａ２Ｃｕ３Ｏ７薄膜红外探测器，系统地测试了器件的特征参数。     

Fabrication and characterization of a depletion-mode ZnS0.07Se0.93 MESFET

We report the fabrication and characterization of a depletion-mode n-channel ZnS_0.07Se_0.93 metal-semiconductor field effect transistor (MESFET). A ZnSSe FET could be a key element in opto-electronic integration consisting of light emitters, light receivers and MESFET pre-amplifiers. Mesa isolation, recess etching and self-alignment techniques were adopted to optimize the MESFET performance. Source and drain (S/D) ohmic contacts and gate Schottky contact were formed by Cr/In/Cr and Au deposition, respectively. Depletion mode FET's with varying gate width-to-length ratio of W/L=200 μm/20 μm, 200 μm/4 μm and 200 μm/2 μm were fabricated. A 2 μm FET was characterized as follows: the turn-on voltage, V_on≈1.75 V, the pinch-off voltage, V_p≈-13 V, the unit transconductance, g_m≈8.73 mS/mm, and the breakdown voltage with zero gate-source bias, BV≈28 V     

Dielectric Characteristics of Ba0.65Sr0.35TiO3 Thin Films by Sol-Gel Method

Ferroelectric Ba0.65Sr0.35TiO3 (BST) thin films on the Pt/Ti/SiO2/Si substrate have been successfully prepared by sol-gel. Such films have approximately 300 nm thicknesses with a remnant polarization of about 2.95 C/cm2 and a coercive field of about 21.5 kV/cm. The investigations of X-ray diffraction and atomic force microscopy show that the BST films annealed at 650 ℃ exhibit a tetragonal structure and that the films dominantly consist of large column or grains of about 89 nm in diameter. The curves of the temperature dependence of dielectric coefficient in different frequencies display the curie transition at the temperature around 23 ℃. The dielectric loss tangent of BST thin films at 100 kHz is less than 0.04. As a result, the BST thin films are more applicable for fabrication of infrared detector compared with the BST thin films reported previously.     

Transport properties and observation of quantum Hall effects of InAs0.1Sb0.9 thin layers sandwiched between Al0.1In0.9Sb layers

InAs_0.1Sb_0.9 active layers sandwiched between Al_0.1In_0.9Sb insulating buffer layers were grown on GaAs (1 0 0) substrates by molecular beam epitaxy. The basic transport properties at room temperature and quantum Hall effects at low temperature of the InAs_0.1Sb_0.9 were studied as a function of InAs_0.1Sb_0.9 thickness. The electron mobility of the InAs_0.1Sb_0.9 active layers had a very high value and very small thickness dependence at less than 500 nm. The quantum Hall effects of the InAs_0.1Sb_0.9 were observed at thicknesses 15, 20, 30, 50, 70, and 100 nm. The observation of the quantum Hall effect at thickness more than 50 nm strongly suggests the existence of two-dimensional electron gas in the InAs_0.1Sb_0.9 layer sandwiched between Al_0.1In_0.9Sb layers.     

基片表面状态对Pb1-xGexTe薄膜红外光学性能的影响

在高真空中用热蒸发的方法沉积了碲锗铅Pb1-xGexTe薄膜。分析了基片表面状态(粗糙度、 晶向、温度)对膜层结构和红外光学特性的影响,发现光滑表面容易得到致密膜层和高红外折射率; 随着沉积温度的增加,膜层的短波吸收边(λc)往长波方向移动。     

用于红外激光防护的VO2薄膜的研究进展

二氧化钒（VO2）薄膜由于具有优异的热致变色性能已成为激光防护材料领域的研究热点.本文综述了国内外VO2薄膜的研究进展,对VO2薄膜的主要制备方法、用于红外激光防护的原理及防护波段进行了探讨,并总结了用VO2薄膜实现激光防护所面临的问题.     

溅射参数为Ge2Sb2Te5薄膜光学常数的影响

研究了溅射参数对Ge2Sb2Te5薄膜的光学常数随波长变化关系的影响。结果表明：（1）当浅射功率一定时,随溅射氩气气压的增加Ge2Sb2Te5薄膜的折射率先增大后减小,而消光系数先减小后增大。（2）当溅射氩气压一定时,对于非晶态薄膜样品,在500nm波长以下,折射率随溅射功率的增加先增加后减小,消光系数则逐渐减小;在500nm以上,折射率随溅射功率的增加逐渐减少,消光系数先减小后增加。 对于晶态薄膜样品,在整个波长范围折射率随溅射功率的增加先减小后增加,消光系数则逐渐减少。（3）薄膜样品的光学常数都随波长的变化而变化,在长波长范围变化较大,短波长范围变化较小,探讨了影响Ge2Sb2Te5薄膜光学常数的机理。     

衬底负偏压及溅射功率对SiO_2/Cu薄膜形貌的影响

采用射频磁控溅射镀膜技术,分别以不同的衬底负偏压和射频溅射功率下在p型Si(100)基片上制备了SiO2/Cu薄膜。用原子力显微镜(AFM)对薄膜的表面形貌进行扫描分析,实验结果表明,衬底负偏压和射频溅射功率对SiO2/Cu薄膜的表面形貌都有显著的影响。衬底负偏压在0～15 V内,薄膜表面颗粒尺寸和均方根粗糙度都随着衬底负偏压的增大呈减小的趋势,而溅射功率在100～200 W内,薄膜表面颗粒尺寸和均方根粗糙度都随溅射功率的升高呈增大的趋势。成膜初期是层状生长模式,后期为岛状生长模式,整个成膜过程是典型的层岛生长模式。     

Resistive Switching Characteristics of Al2O3/ZnO Bilayer Thin Films for Flexible Memory Applications

Unipolar resistive switching behaviors of the ZnO and Al2O3/ZnO films fabricated on flexible substrates by pulse laser deposition were studied in this paper. The films were deposited at room temperature without post-annealing treatment during the process. X-ray diffraction results indicated that ZnO film has a dominant peak at (002). Scanning electron microscopy observation showed a columnar grain structure of the ZnO film to the substrate. The bilayer device of Al2O3/ZnO films had stable resistive switching behaviors with a good endurance performance of more than 200 cycles, high resistive switching ratio of over 103 at a read voltage of 0.1 V, which is better than that of the single oxide layer device of ZnO film. A possible resistive switching filamentary mode was demonstrated in this paper. The conduction mechanisms of high and low resistance states can be explained by space charge limited conduction and Ohmics behaviors. The endurance of the bilayer (BL) device was not degraded upon bending cycles, which indicates the potential of the flexible resistive switching random access memory applications.     

柔性衬底ITO导电膜的低温制备及特性研究

用真空反应蒸发技术在有机薄膜衬底上制备出ＩＴＯ透明导电薄膜,对薄膜的低温制备、结构和光电特性进行了研究,制备的薄膜为多晶膜,具有纯三氧化二铟的立方铁锰矿结构,最佳取向为（１１１）方向。薄膜在可见光区的最低电阻率为６．６３＊１０＾－４Ω．ｃｍ,透过率达到８２％。     

高温红外电热膜的制备与特性研究

采用蒸镀法制备掺杂的二氧化锡电热膜,并研究了溶液成分,掺杂浓度对电热膜的电 阻、电阻温度特性以及红外辐射性能的影响,得到电阻性能稳定且发射率高的高温红外电热膜。