塑料薄膜衬底上复合敏感膜热释电传感器的制备

将Sol-Gel法制备的掺钙钛酸镧铅纳米粉粒(PCLT)与聚偏氟乙烯-三氟乙烯(P(VDF-TrFE)均匀复合,作为热释电传感器的敏感膜,比同样制备条件的纯聚偏氟乙烯-三氟乙烯膜的探测优值高约22.4%。并以沉积有35nmITO薄膜的廉价PET塑料为衬底,用旋转涂膜法沉积PCLT/P(VDF-TrFE)复合敏感膜,用Ni-Cr薄膜作上电极,制备了PCLT/P(VDF-TrFE)/PET热释电传感器。PET塑料可有效降低热释电元件的热导,下电极ITO可反射红外辐射,明显提高了传感器的电压响应和降低热释电元件的热噪声。测试结果表明,PCLT/P(VDF-TrFE)/PET热释电传感器的探测率达到3.4×107cmHz1/2W-1,比同样制备条件的体硅衬底传感器高2个数量级以上。     

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。     

复合热释电薄膜红外探测器的二维热分析

根据热释电薄膜红外探测器的结构和测试条件，使用有限元软件Ansys对其进行了二维热分析，得到了探测器受到红外辐射后的温度场。分析了复合热释电薄膜红外探测器的绝热层对温度场的影响，并将它与微桥结构探测器的性能进行了比较。结果表明，复合热释电薄膜红外探测器的绝热层能有效地减小热流向硅衬底的散失，并且探测器的响应随着绝热层厚度的增大而增大；当复合热释电薄膜红外探测器中绝热层的热导率低于空气的热导率时，它的绝热性能优于微桥结构．     

热释电红外新器件的工作原理及其应用

热释电红外传感器在国民经济和军事中的应用将越来越广泛。其主要部分由热释电红外探测传感器、放大电路及应用电路组成。本文介绍了热释电红外传感技术的基本原理及其应用,以及依据此原理设计的热释电红外电源开关控制、防盗防火报警、自动监测等。     

热释电传感器的应用前景

本文介绍几种典型的热释电材料及器件结构的改进;叙述了一种新型的“热光”转换器;讨论了热释电传感器的应用领域和发展前景。     

热释电红外传感器的技术动态

介绍了LiTaO3、PZT等热释电材料在材料复合、工艺改进与创新方面的研发动态,结合一款单片机控制的热释电红外节能照明开关的设计实例,归纳与展望了热释电红外传感器在节能控制设备、楼宇人数统计以及在安全与军事等多个领域的应用。     

红外热释电材料及热释电系数测试

介绍了某些代表性的热释电材料的性能，并对热释电系数的测量方法作了全面综述，最后对热释电系数测试向计算机化发展作出了展望。     

单片微机红外报警系统的研制

在介绍了热释电红外传感器性质的基础上，研制出一套单片微机红外报警系统，阐述了系统构成和红外报警工作原理，并分析了处理方法和软件程序框图。该系统是用热释电红外传感器和intel8031单片微计算机实现的．     

PLCT系列热释电薄膜的最新研究进展

热释电红外探测器广泛应用于辐射测温，红外光谱测量，安全警戒，红外热成像等领域。掺杂钛酸铅薄膜是性能优异，应用广泛的热释电薄膜，文章主要介绍了镧，钙双掺的钛酸铅薄膜的性能。比较了不同组分的PCT、PLT、PLCT铁电材料的制备方法、结晶性、铁电性、介电性及热释电性能与分组的关系，并对PLT系列热释电薄膜材料的应用前景作了探讨。     

日本用表面微机械加工技术制备成功集成热释电红外传感器阵列

日本丰桥理工大学的研究人员利用表面微机械加工技术首次在外延γ-Al_2O_3/Si衬底上制备出一种带有nMOS/nJFET器件的集成热释电红外传感器阵列。由于热释电和铁电薄膜的取向及结晶度控制对获取高灵敏度热释电红外探测器非常重要,为了把它们控制好,     

一种新型高精度宽电压范围的CMOS温度传感器

介绍了一种用于环境温度监测的新型高精度宽电压范围的CMOS温度传感器,采用0.13μm标准CMOS工艺的厚氧器件实现,芯片面积为37μm×41μm。该温度传感器在-20～60°C的温度范围内,采用两点校正方法之后,温度误差为-0.2°C/0.5°C。该温度传感器可以在1.8～3.6V的电源电压范围内安全可靠地工作,并且具有较高的电源抑制比。测试结果表明,其输出电压斜率为3.9mV/°C,1.8V下功耗为1.3μW。     

Thermal Behavior of Amorphous Silicon Thin Film Transistor and Its Application to Micromachined Uncooled Infrared Sensors

This work reports a new uncooled infrared sensor based on amorphous silicon thin film transistors (a-Si TFTs). The temperature coefficient of channel current (TCC) of the a-Si TFT is given. Analysis shows that the a-Si TFT working in the saturation region is preferred for the sensitive element with a TCC value of 3.8-6.0 %/K. The a-Si TFT is placed on a suspended microbridge to reduce the thermal conductance by using micro-electro-mechanical system (MEMS) technology. The a-Si TFT-based IR sensor with a monolithic architecture is fabricated. Preliminary experimental results show that a responsivity of 40.8 kV/W, a thermal response time of 5.5 ms and a NETD of 90 mK are achieved.     

U型凹槽电极硅MSM结构光电探测器的研制

为了提高硅MSM结构光电探测器的光电响应度,制备了U型凹槽电极结构的探测器.5 V偏压下,对650 nm波长入射光的绝对光电响应度测试表明,凹槽电极结构的探测器最大光电响应度值为0.486 A/W,比同样尺寸的平版结构光电探测器提高了约6倍.文中也对比了具有抗反射膜和不具有抗反射膜的器件相对响应光谱的差别,并且比较分析了叉指间隙分别为5 μm和10 μm器件光电响应的不同.     

非晶硅CCD列阵图像传感器的设计考虑

文中讨论了非晶硅光电二极管及CCD器件的设计考虑。用α－Si：H光电二极管构成CCD器件的光敏元，提高了光敏单元填充因子，并提出了图像传感器的结构和制作工艺。     

Design and implementation of micro-power temperature to duty cycle converter using differential temperature sensing

The CMOS based temperature detection circuit has been developed in a standard 180 nm CMOS technology. The proposed temperature sensor senses the temperature in terms of the duty cycle in the temperature range of −30 °C to +70 °C. The circuit is divided into three parts, the sensor core, the subtractor and the pulse width modulator. The sensor core consists of two individual circuits which generates voltages proportional (PTAT) and complementary (CTAT) to the absolute temperature. The mean temperature inaccuracy (°C) of PTAT generator is −0.15 °C to +0.35 °C. Similarly, CTAT generator has mean temperature accuracy of ±1 °C. To increase thermal responsivity, the CTAT voltage is subtracted from the PTAT voltage. The resultant voltage has the thermal responsivity of 6.18 mV/°C with the temperature inaccuracy of ±1.3 °C. A simple pulse width modulator (PWM) has been used to express the temperature in terms of the duty cycle. The measured temperature inaccuracy in the duty cycle is less than ±1.5 °C obtained after performing a single point calibration. The operating voltage of the proposed architecture is 1.80±10% V, with the maximum power consumption of 7.2 μW.     

热激励谐振型压力传感器激励电压的影响与分析

针对热激励谐振型压力传感器在不同激励电压下会产生不同的热梯度场,进而影响传感器的谐振频率这一现象,采用开环测试系统进行试验,得到热激励谐振型压力传感器的热激励幅度与谐振频率的变化规律;并对实验结果进行了进一步的分析,为合理优化设计传感器的相关参数提供了一定的理论依据.     

A p-silicon nanowire/n-ZnO thin film heterojunction diode prepared by thermal evaporation

This paper represents the electrical and optical characteristics of a SiNW/ZnO heterojunction diode and subsequent studies on the photodetection properties of the diode in the ultraviolet （UV） wavelength region. In this work, silicon nanowire arrays were prepared on p-type （100）-oriented Si substrate by an electroless metal deposition and etching method with the help of ultrasonication. After that, catalyst-free deposition of zinc oxide （ZnO） nanowires on a silicon nanowire （SiNW） array substrate was done by utilizing a simple and cost-effective thermal evaporation technique without using a buffer layer. The SEM and XRD techniques are used to show the quality of the as-grown ZnO nanowire film. The junction properties of the diode are evaluated by measuring current-voltage and capacitance-voltage characteristics. The diode has a well-defined rectifying behavior with a rectification ratio of 190 at -t-2 V, turn-on voltage of 0.5 V, and barrier height is 0.727 eV at room temperature under dark conditions. The photodetection parameters of the diode are investigated in the bias voltage range of ± 2 V. The diode shows responsivity of 0.8 A/W at a bias voltage of 2 V under UV illumination （wavelength = 365 nm）. The characteristics of the device indicate that it can be used for UV detection applications in nano-optoelectronic and photonic devices.     

A novel high-speed silicon MSM photodetector operating at 830 nmwavelength

A novel high-speed silicon photodetector that operates at a wavelength of 830 nm is reported. It consists of a Metal-Semiconductor-Metal (MSM) detector that is fabricated on a 5-μm thick silicon membrane. The detector has a measured -3 dB bandwidth of 3 GHz at 10 V, which is almost one order of magnitude larger than the reported bandwidth of conventional silicon MSM detectors as measured at 830 nm. The DC responsivity is 0.17 A/W, corresponding to an internal quantum efficiency of 60.5% and an external quantum efficiency of 25.4%. The large bandwidth and good responsivity at the wavelength of interest, combined with its low operating voltage and compatibility with most silicon integrated circuit technologies, make this detector a promising candidate for monolithic optoelectronic receiver circuits for use in short distance optical communication systems and computer interconnects     

Effects of the substrate on the response of pyroelectric detectors

In our studies dealing with a theoretical analysis on the response of pyroelectric detectors, it has been found that for substrate-attached pyroelectric detectors, the current responsivity falls off with decreasing frequency below a certain frequency due to the flow of heat out of the pyroelectric crystal into the substrate. The rate of the falloff depends on the thermal conductivity of the substrate. The higher the thermal conductivity, the faster the rate of the falloff. The current responsivity flattens out in a lower intermediate frequency range of 10^-2to 10²Hz. In this flat plateau region, the smaller the substrate thermal capacity, the higher the current responsivity. The theoretical analysis agrees with the experimental results using LiTaO3detectors mounted on silicon substrates.     

The pyroelectric detector of infrared radiation

The pyroelectric detector is a thermal sensor of infra-red radiation requiring no bias. While in principle a pure capacitor (hence theoretically noiseless), the detector has a varying noise contribution as a function of frequency due to a load resistor, series loss resistance, and amplifier. The actual sensor is a pyroelectric crystal exhibiting spontaneous polarization. The spontaneous polarization and dielectric constant of the crystal are temperature-dependent. A change in incident power raises the detector temperature causing an electric charge to appear across the electroded surfaces cut perpendicular to the crystal's ferroelectric axis. Under open circuit conditions, a voltage is obtained which is ultimately neutralized by current flow through the leakage resistance or load resistor. The evacuated detector package incorporates an electroded flake of triglycine sulfate mounted on a substrate of low thermal and electrical conductivity, a field effect transistor, load resistor, and an infrared transparent window. Data on the detectivity, responsivity, and noise as a function of frequency and area are presented. Polycrystalline pyroelectric detectors of TGS are feasible and simplify the construction of arrays and mosaics. Applications of the pyroelectric detector to date have been in a multielement line scanner, thermal imaging camera, spectrometer, and laser calorimeter.