薄膜型热释电探测器红外响应模型分析

在进行热释电焦平面探测器ROIC（读出电路）设计时，必须充分考虑热释电探测器的红外响应特性，并根据探测器等效电路的SPICE模型进行设计仿真。从热释电探测器的热平衡方程出发，在Matlab平台上分析模拟了探测器对脉冲函数调制状态下的瞬态响应，并根据提供的薄膜材料参数在具体应用中建立了热释电探测器的等效电路模型。把探测器等效电路模型与SFD（源跟随器）型输入单元读出电路连接后进行模拟仿真，分析了不同条件下热释电探测器／读出电路组件的响应特性。     

用旋涂法制备的热释电聚合物薄膜研究

PVDF聚合物热释电薄膜是一种新的激光与红外辐射探测器材料,它比无机薄膜更易于与硅微加工工艺为基础的硅读出电路兼容.本文用旋涂法制备了一种聚合物热释电薄膜,对其进行了红外光谱和X射线衍射分析,并研究了其热释电响应特性,结果表明与其他方法(流延法和压膜法)相比,旋涂法制备的聚合物薄膜样品对热响应具有更高的灵敏度,更适合用作激光与红外辐射探测器材料.(PH2)     

多层热释电薄膜红外探测器的PSPICE模型

在分析了热释电探测器工作原理的基础上,利用PSPICE的ABM功能建立了多层薄膜热释电红外探测器的等效电路模型。该模型可以模拟多层薄膜热释电探测器热学和电学特性的暧态响应和频率响应,模拟的结果与实验数据相一致,等效电路模型与读出电路连接,然后对热释电探测器系统进行模拟,分析不同条件下探测器的响应特性。选取不同的电路参数,该模型也同样适用于其他类型的热释电探测器。     

320×240元非制冷红外焦平面阵列读出电路

采用1.2 μm DPDM n阱CMOS工艺设计并研制成功320×240热释电非制冷红外焦平面探测器读出电路.该读出电路中心距为50 μm,功耗小于50 mW,主要由X、Y移位寄存器、列放大器、相关双采样电路等构成,采用帧积分工作方式.经测试,研制的读出电路性能指标达到设计要求.给出了单元读出电路的电路结构、工作过程和参数测试结果.采用该读出电路和热释电红外探测阵列互联后,获得了良好的红外热像.     

有源电阻RTIA红外焦平面读出电路

提出了一种基于有源电阻的电阻反馈跨导放大器(RTIA)红外焦平面读出电路,该电路采用工作在亚阈区的MOS管实现1011 以上的有源大电阻,不仅能与热释电红外探测器的高阻抗良好匹配,而且配合两管共源放大器可针对热释电微弱信号进行高增益电流放大。同时,简单的三管单元结构能够方便地置于像元之下,相比于采用特殊高阻材料实现的RTIA,不附加材料和工艺。经上华0.5 ?滋m CMOS工艺流片验证,在5 V电源电压下,该电路增益40 dB,输出摆幅3 V,在高低温测试下表现出了良好的增益带宽稳定性,适用于PZT和BST等热释电大阵列探测器。     

热释电薄膜在红外探测器中的应用

介绍了热释电效应及热释电薄膜红外探测器的工作模式，特别是探测器单元对热释电薄膜的材料与低温生长要求。为了克服薄膜生长过程中较高的基片温度对读出集成电路(ROIC)的破坏性影响，一方面发展了离子束辅助沉积、外延缓冲层等多种低温生长技术，另一方面发展了复合探测器结构设计。已研制出了性能良好的铁电薄膜非制冷红外焦平面阵列，其噪声等效温差(NEDT)可达20mK。     

基于弛豫铁电单晶的红外热释电探测器研究

研究了新型热释电材料驰豫铁电单晶(1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3(PMNT)的低损伤减薄工艺、电极成型和耦合封装等关键技术,研制了基于PMNT的单元热释电探测器。对减薄后约30μm晶片材料性能的测试分析表明,部分样品的热释电系数约为9.0×10-4 C/m2 K,无明显衰减。采用低噪声电路提取单元探测器的微弱热释电电流,对所研制的单元探测器性能进行了测试分析。     

1×128热释电IRFPA CMOS读出电路的研究

热释电红外焦平面阵列是非致冷红外焦平面阵列的主要发展方向之一 ,其读出电路是关键部件 ,属数模混合集成电路。分析了热释电读出电路的特点 ,设计原则 ,并给出了一种读出电路设计方案以及仿真和实验结果     

钛酸锶钡热释电薄膜及其非制冷红外探测器研究

开展了钛酸锶钡(BST)热释电薄膜材料制备工艺研究,及其在单元器件和焦平面器件中的应用研究.在删Pt/Ti/SiO2/Si衬底上,用倒筒靶射频溅射方法制备了BST热释电薄膜.通过低温缓冲层技术和调控自偏压的方法,降低了BST薄膜的生长温度,提高了BST薄膜的c轴取向度和耐压特性,解决了薄膜制备的均匀性和一致性问题,使薄膜热释电系数达到6.7×10-7Ccm-2K-1.利用微细加工的方法,制备出全集成的BST薄膜单元红外探测器,抗过载能力强,探测器达到8×107cmHz1/2W-1,可以满足"灵巧弹药"的使用要求.实验表明,制备BST热释电薄膜的工艺不会对新型的耐高温读出电路造成破坏,为研制高性能的BST薄膜型焦平面探测器奠定了基础.     

热释电材料及其应用

对热释电材料进行了分类 ,对热释电材料、热释电传感器、热释电探测器的性能作了介绍 ,提出了一些改进热释电材料性能的方法 ,对热释电材料的研究现状和应用前景作了探讨。     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

Influence of polarization extinction ratio on distributed polarization coupling detection

Distributed polarization coupling in polarization-maintaining fibers can be detected by using a white light Michelson interferometer. This technique usually requires that only one polarization mode is excited. However, in practical measurement, the injection polarization direction could not be exactly aligned to one of the principal axes of the PMF, so the influence of the polarization extinction ratio should be considered. Based on the polarization coupling theory, the influence of the incident polarization extinction on the measurement result is evaluated and analyzed, and a method for distributed polarization coupling detection is developed when both two orthogonal eigenmodes are excited.     

Noise character analysis and the restraint of self-pulsation laser diodes

We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.     

High-quality single-crystal CdSe nanoribbons and their optical properties

Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method, in which two-step-thermal-evaporation is used to control CdSe sources＇ evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width, 50 nm in thickness, and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photolumines-cence indicates that the lasing emission at 710 nm has been observed under optical pumping （266 nm） at power densities of 25-153 kW/cm^2. The full width half maximum （FWHM） of the lasing mode is 0.67 nm     

Propagation of hermite-cosh-gaussian beams passing through ABCD optical system with an annular aperture

By using the expansion of the aperture function into a finte sum of complex Gaussian functions, the corresponding analytical expressions of Hermite-cosh-Gaussian beams passing through annular apertured paraxially and symmetrically optical systems written in terms of ABCD matrix were derived, and they could reduce to the cases with squared aperture. In a similar way, the corresponding analytical expressions of cosh-Gaussian beams through annular apertured ABCD matrix were also given. The method could save more calculation time than that by using the diffraction integral formula directly.     

中国建立EB级存储实验室,致力云计算应用(英文)

正With the support of 863 programs,Sugon Information Industry Co.,Ltd.,set up a dawning EB-class storage laboratory to address massive data storage requirements and largescale cloud computing demonstration applications.The Dawning EB-class cloud storage system adopts advanced fault-tolerant architecture,efficient data fault-tolerant algorithms with user authentication and data encryption policies to deal with the"lost""wrong"and"stolen"problems of data for ensuring the reliability and safety of the EB-class storage system in the public network application environments.The Dawning EB-class Storage Laboratory taking advan-