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A Silicon-Based Positive-Intrinsic-Negative Photodetector Double Linear Array on a Thick Intrinsic Epitaxial Layer

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Chinese Physics Letters 2014年第5期31卷 187-190页

作者：袁立吴灿张兆华任天令 Institute of Microelectronics and Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Beijing 100083

To measure small particles in clouds without the optical amplification system, a new type of p-i-n photodetector linear array with 128 diode units altogether is designed and realized. In each die, there are two rows of photodiode line array, and each row has 64 photodiodes. Every photodiode has a size of 100 μm × 100 μm with an individual output, and each of them is isolated by the trenches. The depth of them has the same thickness as that of the epitaxial layer, which is designed to be 30 μm to guarantee sufficient absorption of photons and leave a margin for the diffusion of p-type and n-type region. The detector has been tested with a laser whose wavelength was 650nm and irradiance is 50mW/cm2. The achieved photocurrent is 2μA. Hence, the current responsivity is about 0.4A/W, and the external quantum efficiency is 76.45%. The dark current is less than 600pA. Both of the sufficient absorption of photons and low dark current are achieved by utilizing the thick epitaxial intrinsic layer. Low interference of adjacent photodiodes is also guaranteed by the trenches around the photodiodes. With the obtained performance, the photodetector can be used to measure the diameter of precipitation particles in clouds. Therefore, rainfall can be judged based on the diameter of particles.

关键词： PHOTODETECTORS EPITAXIAL layers photodiodes QUANTUM efficiency (Physics) PRINTED circuits

Theoretical Investigations of the Physical Properties of Cd1-xCaxO Ternary Alloys

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Chinese Physics Letters 2014年第4期31卷 105-109页

作者： S. Labidi A. Lakel M. Labidi R. Bensalem Departrrlent of Physics Faculty of Sciences Badji Mokhtar University P. O. Box 12 23000 Annaba Algeria

The structural, electronic and thermodynamic properties of Cd1-x CaxO ternary alloys are calculated using the first principles calculations performed within the framework of density functional theory. The exchange correlation potential for structural properties is calculated by the standard generalized gradient approximation （GGA） of Perdew et al., while for the electronic properties, the modified Becke-Johnson （MB3） scheme is also applied. A deviation of the lattice constants from Vegard＇s law and bulk modulus from linear concentration dependence （LCD） are observed for the alloys. In addition, the thermodynamic stability of the alloys is investigated by calculating the critical temperatures of alloys.

关键词： MATTER -- Properties TERNARY alloys DENSITY functional theory photodiodes SEMICONDUCTORS

Single-Photon Detection at Telecom Wavelengths

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Chinese Physics Letters 2007年第2期24卷 574-576页

作者：孙志斌马海强雷鸣王迪刘赵杰杨捍东吴令安翟光杰冯稷 Institute of Physics Chinese Academy of Sciences Beijing 100080

A single-photon detector based on an InGaAs avalanche photodiode has been developed for use at telecom wavelengths. A suitable delay and sampling gate modulation circuit are used to prevent positive and negative transient pulses from influencing the detection of true photon induced avalanches. A monostable trigger circuit eliminates the influence of avalanche peak jitter, and a dead time modulation feedback control circuit decreases the afterpulsing. From performance tests we lind that at the optimum operation point, the quantum efficiency is 12% and the dark count rate 1.5 × 10^-6 ns^-1, with a detection rate of 500 kHz.

关键词： AVALANCHE PERFORMANCE photodiodes

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Organic optocouplers

Science China Chemistry 2011年第7期54卷 1017-1026页

作者： SUN QiuJian DONG GuiFang WANG LiDuo QIU Yong Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China

Organic optocoupler(OOC) or organic photocoupler,optical coupler is a novel and one of the most promising organic optoelectronic devices for its well electrical isolation and anti-jamming ability in long-distance and real-time digital *** performance parameters of OOC were greatly raised during the past decade,and its development was strongly associated with basic organic devices such as organic light emitting diodes(OLED),organic photodiodes(OPD) and organic phototransistors(OPT) *** we describe the principles of OOC,review recent breakthroughs in this field,and summarize the photosensor and light emitting parts which could be used in the *** technical points,such as current transfer ratio,frequency,matching and stability were also discussed in this paper.

关键词： organic optocoupler organic photocoupler photodiodes phototransistors light emitting diode current transfer ratio cut-off frequency

Design, Fabrication, and Modeling of CMOS-Compatible Double Photodiode

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Transactions of Tianjin University 2017年第2期23卷 163-167页

作者： Sheng Xie Xuetao Luo Luhong Mao Haiou Li School of Microelectronics Tianjin University Guangxi Key Laboratory of Precision Navigation Technology and Application Guilin University of Electronic Technology

A double photodiode (PD) constructed by p+/N-well junction and N-well/p-sub junction was designed and fabricated in a UMC 0.18-μm CMOS process. Based on the device structure and mechanism of double PD, a novel small-signal equivalent circuit model considering the carrier transit effect and the parasitic RC time constant was presented. By this model with complete electronic components, the double PD can be incorporated in a commercial circuit simulator. The component values were extracted by fitting the measured S-parameters using simulated annealing algorithm, and a good agreement between the measurement and the simulation results was achieved. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg.

关键词： Circuit theory CMOS integrated circuits Equivalent circuits Heterojunction bipolar transistors Integrated circuit design photodiodes Scattering parameters Simulated annealing

InGaAs Photodetectors Cut-off at 1.9μm Grown by Gas-Source Molecular Beam Epitaxy

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Chinese Physics Letters 2005年第1期22卷 250-253页

作者：张永刚郝国强顾溢朱诚李爱珍刘天东 StateKeyLaboratoryofFunctionalMaterialsforInformatics ShanghaiInstituteofMicrosystemandInformationTechnologyChineseAcademyofSciencesShanghai200050

Using a linear graded InxGa1-xAs as the buffer layer,positive-intrinsic-negative wavelength-extended In0.6Ga0.4 As photodetectors with 50% cut-offwavelength of 1.9mum at room temperature were grown by using gas-source molecular beam epitaxy, andtheir performance over a wide temperature range has been extensively investigated. The detectorsshow typical dark current at bias voltage 50mV and the resistance-area product R(0)A of7nA/765Omegacm(2) and 31pA/404kOmegacm(2) at 290K and 210K, respectively. The thermal activationenergy of the dark current in the temperature range 250-350K is 0.488eV.

关键词： VAPOR-PHASE EPITAXY DARK CURRENT photodiodes WAVELENGTH

Development on Si optoelectronic receiving and processing chip

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Development on Si optoelectronic receiving and processing ch...

Enhanced solar-blind ultraviolet single-photon detection with a Geiger-mode silicon avalanche photodiode

2006 8th International Conference on Solid-State and Integrated Circuit Technology

作者： Yang Weidong Zhang Zhengfan Li Kaicheng Ou Hongqi Huang Wengang National key Labs of Analog IC of China

ISBN: (纸本)1424401607

＜正＞In this study,a monolithic optoelectronic integrated circuit（OEIC）,in which a photodiode detector and a bipolar integrated circuit for reception and amplification are integrated on the same silicon substrate,is described. With the new process technology,the layout of optical and electronic devices is designed,and the processes of optical and electronic devices are *** a good way of developing high performance,high reliability,cost effective optoelectronic integrated circuit has been found.

关键词： Optical devices Bipolar integrated circuits Stimulated emission Monolithic integrated circuits Optoelectronic devices photodiodes Detectors Silicon Integrated circuit technology Optical design

来源： cnki会议评论

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Chinese Optics Letters 2016年第3期14卷 5-8页

作者：师亚帆李召辉冯百成颜佩琴杜秉乘周慧潘海峰吴光 State Key Laboratory of Precision Spectroscopy East China Normal University State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences

Solar-blind ultraviolet detection is of great importance in astronomy and industrial and military applications. Here, we report enhanced solar-blind ultraviolet single-photon detection by a normal silicon avalanche photo- diode （Si APD） single-photon detector with a specially designed photon-collecting device. By re-focusing the reflected photon from the Si chip surface on the detection area by the aluminum-coated hemisphere, the detec- tion efficiency of the Si APD at 280 nm can be improved to 4.62%. This system has the potential for high-efficiency photon detection in the solar-blind ultraviolet regime with low noise.

关键词： Aluminum coatings Avalanche photodiodes Efficiency Military applications Photodetectors photodiodes Photons Silicon

Characteristics of the CsI:Tl Scintillator Crystal for X-Ray Imaging Applications

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Materials Sciences and Applications 2018年第2期9卷 268-280页

作者： Maria da Conceicao Costa Pereira Tufic Madi Filho Jose Roberto Berretta Carlos Henrique de Mesquita Nuclear and Energy Research Institute—IPEN/CNEN-SP Sao PauloBrazil

Scintillators are high-density luminescent materials that convert X-rays to visible light. Thallium doped cesium iodide (CsI:Tl) scintillation materials are widely used as converters for X-rays into visible light, with very high conversion efficiency of 64.000 optical photons/MeV. CsI:Tl crystals are commercially available, but, the possibility of developing these crystals into different geometric shapes, meeting the need for coupling the photosensor and reducing cost, makes this material very attractive for scientific research. The objective of this work was to study the feasibility of using radiation sensors, scintillators type, developed for use in imaging systems for X-rays. In this paper, the CsI:Tl scintillator crystal with nominal concentration of the 10-3 M was grown by the vertical Bridgman technique. The imaging performance of CsI:Tl scintillator was studied as a function of the design type and thickness, since it interferes with the light scattering and, hence, the detection efficiency plus final image resolution. The result of the diffraction X-ray analysis in the grown crystals was consistent with the pattern of a face-centered cubic (fcc) crystal structure. Slices 25 × 2 × 3 mm3 (length, thickness, height) of the crystal and mini crystals of 1 × 2 × 3 mm3 (length, thickness, height) were used for comparison in the imaging systems for X-rays. With these crystals scintillators, images of undesirable elements, such as metals in food packaging, were obtained. One-dimensional array of photodiodes and the photosensor CCD (Coupled Charge Device) component were used. In order to determine the ideal thickness of the slices of the scintillator crystal CsI:Tl, Monte Carlo method was used.

关键词： Crystal Growth Scintillator X-Ray Imaging Systems photodiodes Coupled Charge Device