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Journal of Semiconductors 2011年第6期32卷 1-6页

作者： Ken K.Chin Department of Physics and Apollo CdTe Solar Energy Research Center New Jersey Institute of Technology

We present a generic approximate graphical method for determining the equilibrium Fermi level and majority carrier density of a semiconductor with multiple donors and multiple acceptors compensating each other. Simple and easy-to-follow procedures of the graphical method are *** graphically plotting two wrapping step functions facing each other,one for the positive hole-ionized donor and one for the negative electron-ionized acceptor,we have the crossing point that renders the Fermi level and majority carrier *** the graphical method,new equations are derived,such as the carrier compensation proportional to N;/N;,not the widely quoted N;-N;.Visual insight is offered to view not only the result of graphic determination of Fermi level and majority carrier density but also the dominant and critical pair of donors and acceptors in *** graphical method presented in this work will help to guide the design,adjustment,and improvement of the multiply doped *** of this approximate graphical method with previous work on compensation,and with some experimental results,is *** work in the field is proposed.

关键词： doping compensation Fermi level carrier density graphical method ionization

Modulating carrier density of the(Ag)_(x)(MoO_(3))_(y)system to enhance SERS:Localized surface plasmon resonance contribution

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Journal of Materiomics 2023年第2期9卷 387-394页

作者： Lin Zhu Zhu Mao Peng Li Menglei Xu Zhen Meng Lei Chen Bing Zhao Stake Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun130012China School of Chemistry and Life Science Advanced Institute of Materials ScienceChangchun University of Technology Changchun130012China Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education Jilin Normal UniversityChangchun130103China

Semiconductors typically exhibit long-wavelength LSPR absorption in the infrared region due to lower carrier *** the carrier density of semiconductors and blue-shifting their LSPR absorption to the visible and near-infrared region has always been a great ***,we discussed how the controllable carrier of(Ag)x(MoO_(3))y composite influences the LSPR based on SERS test and UVeViseNIR absorption *** were surprised to find that the LSPR absorption wavelength can be easily tuned from 950 to 735 nm by changing the sputtering power of MoO_(3)of the(Ag)x(MoO_(3))_(y)*** shows that LSPR can be precisely adjusted by increasing the semiconductor content and even the carrier *** addition,the carrier density was measured by Hall effect to investigate the SERS intensity change caused by electromagnetic(EM)enhancement,and obtain the relationship between the *** findings of this work provide an idea for tunable LSPR and the research of EM contributions to SERS.

关键词： carrier density Localized surface plasmon resonance Semiconductor Electromagnetic Surface-enhanced Raman scattering

Analytical formulas for carrier density and Fermi energy in semiconductors with a tight-binding band

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Journal of Semiconductors 2015年第4期36卷 7-10页

作者：曹文翰 Department of Communication Science and Engineering Fudan University

Analytical formulas for evaluating the relation of carrier density and Fermi energy for semiconductors with a tight-binding band have been proposed. The series expansions for a carrier density with fast convergency have been obtained by means of a Bessel function. A simple and analytical formula for Fermi energy has been derived with the help of the Gauss integration method. The results of the proposed formulas are in good agreement with accurate numerical solutions. The formulas have been successfully used in the calculation of carrier density and Fermi energy in a miniband superlattice system. Their accuracy is in the order of 10-5.

关键词： analytical formulas carrier density Fermi energy tight-binding band

Ion doping simultaneously increased the carrier density and modified the conduction type of Sb_(2)Se_(3) thin films towards quasi-homojunction solar cell

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Journal of Materiomics 2021年第6期7卷 1324-1334页

作者： Guangxing Liang Xingye Chen Donglou Ren Xiangxing Jiang Rong Tang Zhuanghao Zheng Zhenghua Su Ping Fan Xianghua Zhang Yi Zhang Shuo Chen Shenzhen Key Laboratory of Advanced Thin Films and Applications Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China Univ Rennes CNRSISCR(Institut des Sciences Chimiques de Rennes)UMR 6226F-35000RennesFrance Tianjin Key Laboratory of Photoelectronic Thin Film Devices and Technology Renewable Energy Conversion and Storage CenterNankai UniversityTianjin300350China

Antimony selenide(Sb_(2)Se_(3))has drawn tremendous research attentions in recent years as an environment-friendly and cost-efficient photovoltaic ***,the intrinsic low carrier density and electrical conductivity limited its scope of *** this work,an effective ion doping strategy was implemented to improve the electrical and photoelectrical performances of Sb_(2)Se_(3) thin *** Sn-doped and I-doped Sb_(2)Se_(3) thin films with controllable chemical composition can be prepared by magnetron sputtering combined with post-selenization treatment based on homemade plasma sintered *** a result,the Sn-doped Sb_(2)Se_(3) thin film exhibited a great increase in carrier density by several orders of magnitude,by contrast,a less increase with one order of magnitude was achieved for the Idoped Sb_(2)Se_(3) thin ***,such cation or anion doping could simultaneously modify the conduction type of Sb_(2)Se_(3),enabling the first fabrication of a substrate structured Sb_(2)Se_(3)-based quasihomojunction thin film solar cell with configuration of Mo/Sb_(2)Se_(3)-Sn/Sb_(2)Se_(3)-I/ITO/*** obtained power conversion efficiency exceeding 2%undoubtedly demonstrated its attractive photovoltaic application potential and further investigation necessity.

关键词： Sb_(2)Se_(3) Thin film Ion doping carrier density Quasi-homojunction solar cell

Logarithmic Gain-carrier density Characteristic of QW Lasers

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Semiconductor Photonics and Technology 2000年第2期6卷 73-76页

作者： ZHANGXiao－xia CHENJian－guo 等 SouthwestJiaotongUniversity Chengdu610031CHN SichuanUniversity Chengdu610064CHN

The relationship between gain and carrier density is analysed. In the quantum well (QW) lasers, initially, the gain increases rapidly with the carrier density and then starts to saturate. It can be seen that QW lasers have a higher differential gain because of the step-like state density, and that the gain saturates at higher carrier densities because of the constant state density of the lowest subband. It is shown that simple logarithmic gain-carrier density is more accurate than the traditional linearized form for a QW laser.

关键词： Logarithmic gain carrier density Differential gain QW laser

Contactless probing of the intrinsic carrier transport single-walled carbon nanotubes

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Nano Research 2014年第11期7卷 1623-1630页

作者： Yize Stephanie Li Jun Ge Jinhua Cai Jie Zhang Wei Lu Jia Liu Liwei Chen Suzhou Institute of Nano-Tech and Nono-Bionics Chinese Academy of Sciences Suzhou Jiongsu 215123 Chino Present address: Department of Materials Science and Engineering University of Wisconsin-Madison Madison W153 706 USA Present address: Molecular Foundry Lawrence Berkeley National Laboratory Berkeley CA 94720 USA

Intrinsic carrier transport properties of single-walled carbon nanotubes have been probed by two parallel methods on the same individual tubes： The contactless dielectric force microscopy （DFM） technique and the conventional field-effect transistor （FET） method. The dielectric responses of SWNTs are strongly correlated with electronic transport of the corresponding FETs. The DC bias voltage in DFM plays a role analogous to the gate voltage in FET. A microscopic model based on the general continuity equation and numerical simulation is built to reveal the link between intrinsic properties such as carrier concentration and mobility and the macroscopic observable, i.e. dielectric responses, in DFM experiments. Local transport barriers in nanotubes, which influence the device transport behaviors, are also detected with nanometer scale resolution.

关键词： single-walled carbon nanotubes electronic transport dielectric force microscopy field-effect transistor carrier density carrier mobility

Thermomagnetic effect with microtemperature in a semiconducting photothermal excitation medium

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Applied Mathematics and Mechanics(English Edition) 2018年第6期39卷 783-796页

作者： K.LOTFY R.KUMAR W.HASSAN M.GABR Department of Mathematics Faculty of ScienceZagazig University Department of Mathematics Kurukshetra University Mathematics and Physics Department Faculty of EngineeringPort Said University

The main goal of this paper is to focus on the investigation of interaction between a magnetic field and elastic materials with microstructure, whose microelements possess microtemperatures with photothermal excitation. The elastic-photothermal prob- lem in one-dimension is solved by introducing photothermal excitation at the free surface of a semi-infinite semiconducting medium （semiconductor rod）. The integral transform technique is used to solve the governing equations of the problem under the effect of the microtemperature field. The analytical expressions for some physical quantities in the physical domain are obtained with the heating boundary surface and free traction. The numerical inversion technique is used to obtain the resulting quantities in the physical domain. The obtained numerical results with some comparisons are discussed and shown graphically.

关键词： photothermal theory carrier density magnetic field microtemperature Laplace transform

UV illumination enhanced desorption of oxygen molecules from monolayer MoS2 surface

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Nano Research 2020年第2期13卷 358-365页

作者： Yuhang Wang Zhiquan He Jinbing Zhang Hao Liu Xubo Lai Boyang Liu Yibao Chen Fengping Wang Liuwan Zhang Department of Applied Plhysics School ofMathematics and PhysicsUniversity of Science and Techmology BejingBeijing 10083China State Key Laboratory of Low-Dimensional Quantum Physics Collaborative Innovation Center of Quantum MatterDepartment of PhysicsTsinghua UniversityBeijing 100084China

The oxygen adsorption can drastically alter the electronic properties of the two-dimensional(2D)materials,which is usually dificult to be *** this work,we report the ultraviolet(UV)ilumination induced desorption of the O2 molecules from the monolayer MoS2 surface by using the atmosphere dependent transport measurement,Kelvin probe microscopy,photoluminescence spectroscopy and X-ray photoelectron *** increasing of the conductivity,rising of the Fermi level,and red shift of the photoluminescence peaks of the MoS2 were observed after the UV ilumination in vacuum,indicating the elimination of the depletion effect from the oxygen *** parameter changes can be reversibly recovered by the subsequent O2 ***,obvious decreasing of the oxygen concentration after the UV ilumination was also observed by X-ray photoelectron *** the UV induced O2 photodesorption effect is *** photo-excited charge transfer mechanism is proposed to account for the photodesorption *** results provide a nondestructive way to clean the MoS2 surface and manipulate the performance of the MoS2 based devices.

关键词： MoS2 desorption ultraviolet(UV)ilumination oxygen adsorption carrier density

Near-Infrared Femtosecond Laser Induced Defect Formation in High Purity Silica Below the Optical Breakdown Threshold

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Chinese Physics Letters 2003年第10期20卷 1763-1766页

作者：周秦岭刘丽英徐雷王文澄朱从善于福熹 ShanghaiInstituteofOpticsandFineMechanics ChineseAcademyofSciencesShanghai201800 StateKeyLaboratoryforAdvancedPhotonicMaterialsandDevices DepartmentofOpticalScienceandEngineeringFudanUniversityShanghai200433 PhotonCraftProject ShanghaiInstituteofOpticsandFineMechanicsChineseAcademyofSciencesShanghai201800

Optical absorption, electron spin resonance and photoluminescence spectra were used to study the defect formation in high purity fused silica induced by a focused infrared femtosecond laser with the input intensity below damage threshold. Si E' centres were formed in the silica. The number of Si E' centre was found increasing linearly with power density of the fs laser, deviated from the increment photo-induced free carrier density. We concluded that the colour centres were formed at the defect sites that were newly generated by radiolysis of silica tetrahedral network and displacement of oxygen between two silicon atoms. Material structure is already modified even though the irradiation fs laser power was well below the damage threshold.

关键词： Optical breakdown Radiolysis purity Yield point causes of defect color centers femtosecond laser carrier density

Studying　the　Mode－Spectra　Characteristics　of　An　Above－Threshold　Biased　Semiconductor　Laser

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Chinese Journal of Lasers 1994年第1期B3卷 11-16页

作者： XIA Guangqiong WU Zhengmao CHEN Jianguo LU Yucun(Optoelectronics Department, Sichuan University,Chengdu 610064, China) Sichuan Univ Chengdu China

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关键词： semiconductor laser ray trace method mode suppression ratio carrier density