检索结果-南通市图书馆

Investigation on n-Type(-201)β-Ga_(2)O_(3)Ohmic Contact via Si ion implantation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2023年第1期28卷 150-154页

作者： Peipei Ma Jun Zheng Yabao Zhang Zhi Liu Yuhua Zuo Buwen Cheng State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Heavy doped n-typeβ-G_(2)O_(3)(HD-G_(2)O_(3))was obtained by employing Si ion implantation technology on unintentionally dopedβ-G_(2)O_(3)single crystal substrates.To repair the G_(2)O_(3)lattice damage and activate the Si after implantation,the implanted substrates were annealed at 950℃,1000℃,and 1100℃,respectively.High-resolution X-ray diffraction and high-resolution transmission electron microscopy show that the ion-implanted layer has high lattice quality after high-temperature annealing at 1000℃.The minimum specific contact resistance is 9.2×10^(-5)Ω·cm^(2),which is attributed to the titanium oxide that is formed at the Ti/G_(2)O_(3)interface via rapid thermal annealing at 480℃.Based on these results,the lateralˇ-G_(2)O_(3)diodes were prepared,and the diodes exhibit high forward current density and low specific on-resistance.

关键词： β-Ga_(2)O_(3) ohmic contact ion implantation annealing activatio

Surface metallization of PTFE and PTFE composites by ion implantation for low-background electronic substrates in rare-event detection experiments

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2022年第7期33卷 37-47页

作者： Shao-Jun Zhang Yuan-Yuan Liu Sha-Sha Lv Jian-Ping Cheng Bin Liao Pan Pang Zhi Deng Li He College of Nuclear Science and Technology Beijing Normal UniversityJoint Laboratory of Jinping Ultra-low Radiation Background Measurement of Ministry of Ecology and Environment Beijing Normal UniversityKey Laboratory of Beam Technology of Ministry of EducationBeijing Normal UniversityBeijing100875China Beijing Radiation Center Beijing100875China Department of Engineering Physics Key Laboratory of Particle and Radiation Imaging of Ministry of EducationTsinghua UniversityBeijing100084China Joint Research Center Nuctech Company LimitedBeijing100084China

Polytetrafluoroethylene(PTFE)is a low-background polymer that is applied to several applications in rare-event detection and underground low-background experiments.PTFE-based electronic substrates are important for reducing the detection limit of high-purity germanium detectors and scintillator calorimeters,which are widely applied in dark matter and 0υββdetection experiments.The traditional adhesive bonding method between PTFE and copper is not conducive to working in liquid nitrogen and extremely low-temperature environments.To avoid adhesive bonding,PTFE must be processed for surface metallization owing to the mismatch between the PTFE and copper conductive layer.Low-background PTFE matrix composites(m-PTFE)were selected to improve the electrical and mechanical properties of PTFE by introducing SiO_(2)/TiO_(2) particles.The microstructures,surface elements,and electrical properties of PTFE and m-PTFE were characterized and analyzed following ion implantation.PTFE and m-PTFE surfaces were found to be broken,degraded,and cross-linked by ion implantation,resulting in C=C conjugated double bonds,increased surface energy,and increased surface roughness.Comparably,the surface roughness,bond strength,and conjugated double bonds of m-PTFE were significantly more intense than those of PTFE.Moreover,the interface bonding theory between PTFE and the metal copper foil was analyzed using the direct metallization principle.Therefore,the peel strength of the optimized electronic substrates was higher than that of the industrial standard at extremely low temperatures,while maintaining excellent electrical properties.

关键词： Surface modification Polytetrafluoroethylene ion implantation Surface metallization Low temperature resistance

Oxygen vacancies and V co-doped Co_(3)O_(4) prepared by ion implantation boosts oxygen evolution catalysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2021年第10期30卷 73-78页

作者：孙博贺栋王宏博刘江超柯尊健程莉肖湘衡 Department of Physics Hubei Nuclear Solid Physics Key LaboratoryWuhan UniversityWuhan 430072China

Introducing heteroatoms and defects is a significant strategy to improve oxygen evolution reaction(OER)performance of electrocatalysts.However,the synergistic interaction of the heteroatom and defect still needs further investigations.Herein,we demonstrated an oxygen vacancy-rich vanadium-doped Co_(3)O_(4)(V-Ov-Co_(3)O_(4)),fabricated by V-ion implantation,could be used for high-efficient OER catalysis.X-ray photoelectron spectra(XPS)and density functional theory(DFT)calculations show that the charge density of Co atom increased,and the reaction barrier of reaction pathway from O∗to HOO∗decreased.V-Ov-Co_(3)O_(4) catalyst shows a low overpotential of 329 mV to maintain current density of 10 mA·cm^(−2),and a small Tafel slope of 74.5 mV·dec^(−1).This modification provides us with valuable perception for future design of heteroatom-doped and defect-based electrocatalysts.

关键词： ion implantation oxygen vacancy oxygen evolution reaction heteroatom doping

Nanograins on Ti-25Nb-3Mo-2Sn-3Zr alloy facilitate fabricating biological surface through dual-ion implantation to concurrently modulate the osteogenic functions of mesenchymal stem cells and kill bacteria

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第14期73卷 31-44页

作者： Run Huang Lei Liu Bo Li Liang Qin Lei Huang Kelvin W.K.Yeung Yong Han School of Materials Science and Engineering Anhui University of Science and TechnologyHuainan232001China Department of Orthopaedics and Traumatology The University of Hong KongHong KongChina State-key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi'an710049China Department of Gastrointestinal Surgery Hubei Cancer HospitalWuhan430060China Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma The University of Hong Kong Shenzhen HospitalShenzhen518053China

Surface mechanical attrition treatment(SMAT)method is an effective way to generate nanograined(NG)surface on Ti-25 Nb-3 Mo-2 Sn-3 Zr(wt.%)(named as TLM),a kind ofβ-type titanium alloy,and the achieved nanocrystalline surface was proved to promote positive functions of osteoblastic cells.In this work,to further endow the NG TLM alloy with both good osteogenic and antibacterial properties,magnesium(Mg),silver(Ag)ion or both were introduced onto the NG TLM surface by ion implantation process,as a comparison,the Mg and Ag ions were also co-implanted onto coarsegrained(CG)TLM surface.The obtained results show that subsequent ion implantation does not remarkably induce the surface roughness and topography alteration of the SMAT-treated layers,and it also has little impact on the microstructure of the SMAT-derivedβ-Ti nanograins.In addition,the implanted Mg and Ag ions are observed to exist as MgO and metallic Ag na noparticles(NPs)embedding tightly in theβ-Ti matrix with grain size of about 15 and 7 nm,respectively.Initial cell adhesion and functions(including proliferation,osteo-differentiation and extracellular matrix mineralization)of rabbit bone marrow mesenchymal stem cells(rBMMSCs)and the bacterial colonization of Staphylococcus aureus(S.aureus)on the different surfaces were investigated.The in-vitro experimental results reveal that the Mg and Ag single-ion implanted NG surface either significantly promotes the rBMMSCs response or inhibits the growth ofS.aureus,whereas the Mg/Ag coimplanted NG surface could concurrently enhance the rBMMSCs functions as well as inhibit the bacterial growth compared to the NG surface,and this efficacy is more pronounced as compared to the Mg/Ag co-implantation in the CG surface.The SMAT-achieved nanograins in the TLM surface layer are identified to not only play a leading role in determining the fate of rBMMSCs but also facilitate fabricating dualfunctio nal surface with both good osteogenic and antibacterial activities through co-implantation of Mg and Ag ions.Our investigation pr

关键词： β-Type titanium Nanograined surface ion implantation Stem cells Antibacterial property

Structural and size evolution of indium nanoparticles embedded in aluminum synthesized by ion implantation

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2017年第12期26卷 377-380页

作者：晏艳霞刘孟胡梅娟朱宏志王欢 Institute of Materials China Academy of Engineering Physics Jiangyou 621907 China

The structural and the size evolution of embedded In nanoparticles in Al synthesized by ion implantation and subsequent annealing are experimentally investigated. The average radius r of In nanoparticles is determined as a function of annealing time in a temperature range between 423 K and 453 K. The structural transition of In nanoparticles with the crystallographic orientation In(200)[002] Al(200)[002] is observed to change into In(111)[110] Al(002)[110] with a critical particle radius between 2.3 nm and 2.6 nm. In addition, the growth of In nanoparticles in the annealing process is evidently governed by the diffusion limited Ostwald ripening. By further analyzing the experimental data, values of diffusion coefficient and activation energy are obtained.

关键词： ion implantation indium nanoparticles size evolution

LiNbO_(3) channel and ridge waveguides based on helium ion implantation combined with lithography and precise diamond dicing

在线全文

学校读者我要写书评

暂无评论

Chinese Optics Letters 2022年第7期20卷 13-17页

作者：王素梅赵金花谷金军卜铭洋范丽李爽秦希峰姚一村任莹莹王磊 School of Science Shandong Jianzhu UniversityJinan 250101China Shandong Key Laboratory of Optical Communication Science and Technology School of Physical Science and Information TechnologyLiaocheng UniversityLiaocheng 252059China Shandong Provincial Engineering and Technical Center of Light Manipulations&Shandong Provincial Key Laboratory of Optics and Photonic Device School of Physics and ElectronicsShandong Normal UniversityJinan 250014China School of Physics Shandong UniversityJinan 250100China

Lithium niobate(LiNbO_(3),LN)channel and ridge waveguides have been successfully fabricated by He ion implantation,which has energy of 500 keV and fluence of 1.5×10^(16)ions/cm^(2) and is combined with lithography and the precise diamond dicing technique.The refractive index profile of the annealed LN planar waveguide was reconstructed.The propagation loss of the channel waveguide with a width of 10μm and that of the ridge waveguides with widths of 25μm and 15μm were investigated by the end-face coupling method.In our work,the factors that affect the waveguide properties of channel and ridge waveguides were revealed.

关键词： lithium niobate waveguides ion implantation ridge waveguide channel waveguide

Diluted magnetic characteristics of Ni-doped AIN films via ion implantation

在线全文

学校读者我要写书评

暂无评论

Frontiers of Optoelectronics 2017年第4期10卷 363-369页

作者： Chong ZHAO Qixin WAN Jiangnan DAI Jun ZHANG Feng WU Shuai WANG Hanling LONG Jingwen CHEN Cheng CHEN Changqing CHEN Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan 430074 China

The structural and magnetic properties, as well as the mechanism of magnetization, of Ni-implanted AIN films were studied. AIN was deposited on Al_2O_3 substrates by metalorganic chemical vapor deposition (MOCVD), and subsequently Ni ions were implanted into the AIN films by Metal Vapor Arc (MEWA) sources at an energy of 100 keV for 3 h. The films were annealed at 900°C for 1 h in the furnace in order to transfer the Ni ions from interstitial sites to substitutional sites in AIN, thus activating the Ni~(3+) ions. Characterizations were performed in situ using X-ray diffraction (XRD), X-ray photoemis-sion spectroscopy (XPS), and vibrating sample magneto-metry (VSM), which showed that the films have a wurtzite structure without the formation of a secondary phase after implanting and annealing. Ni ions were successfully implanted into substitutional sites of AIN films, and the chemical bonding states are Ni-N. The apparent hysteresis loops prove that the films exhibited magnetism at 300 K. The room temperature (RT) saturation magnetization moment (M_s) and coercivity (H_c) values were about 0.36 emu/g and 35.29 Oe, respectively. From the first-principles calculation, a total magnetic moment of 2.99 μB per supercell is expected, and the local magnetic moment of a NiN_4 tetrahedron, 2.45 μB, makes the primary contribution. The doped Ni atom hybridizes with four nearby N atoms in a NiN_4 tetrahedron; then the electrons of the N atoms are spin-polarized and couple with the electrons of the Ni atom with strong magnetization, which results in magnetism. Therefore, the p-d exchange mechanism between Ni-3d and N-2p can be the origin of the magnetism. It is expected that these room temperature, ferromagnetic, Ni-doped AIN films will have many potential applications as diluted magnetic semiconductors.

关键词： III-V nitrides metalorganic chemical vapor deposition (MOCVD) diluted magnetic semiconductors first-principles Magnetic moment Room temperature ion implantation tetrahedrons Magnetism Nickel Atoms Metallorganic chemical vapor deposition Semimagnetic semiconductors Films Geomagnetic field

Effect of Ce~+ ion implantation upon Oxidation Resistance of Superalloy K38G

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2005年第1期23卷 63-67+3页

作者：钱余海李美栓多树旺赵有明 Technology Center Baoshan Iron & Steel Co. Ltd. Shanghai 201900 China Shenyang National (Laboratory) for Materials Sciences Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Shenyang National (Laboratory) for Materials Sciences Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Jiangsu Electric Power No.3 Construction Engineering Company Zhenjiang 212000 China

The oxidation behavior （isothermal and cyclic oxidation） of cast superalloy K38G and the effect of Ce+ ion implantation with dose of 1×1017 ions/cm2 upon its oxidation resistance at 900 and 1000 ℃ in air were investigated. Meanwhile, the influence of Ce+ implantation on oxidation behavior of K38G with pre-oxide scale at 1000 ℃ in air was compared. The pre-oxidation was performed at 1000 ℃ in static air for 0.25 and 1.5 h, respectively. It is shown that the homogeneous external mixture oxide of rutile TiO2+Cr2O3 and non-continuous internal oxide of Al2O3 are formed during the oxidation procedure in all the cases. The isothermal oxidation resistance and the cracking or spallation resistance of superalloy K38G implanted with Ce+ by both of the two different implantation ways are not improved notably. This may be attributed to the mixed oxide composition characteristics and the blocking effect differences of Ce+ segregation along the oxide grain boundaries on the transport process for different diffusing ions.

关键词： high temperature oxidation oxidation resistance ion implantation superalloy K38G rare earths

Capacitance of High-Voltage Coaxial Cable in Plasma Immersion ion implantation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2001年第1期17卷 41-42页

作者： X.B.Tian L.P.Wang D.T.K.Kwok B.Y Tang P.K.Chu Department of Physics&Materials Science City University of Hong KongHong KongChina

Plasma immersion ion implantation (PIII) is an excellent technique for the surf see modification of complex-shaped components. Owing to pulsed operation mode of the high voltage and large slew rate, the capacitance on the high-voltage coaxial cable can be detrimental to the process and cannot be ignored. In fact, a significant portion of the rise-time/fall-time of the implantation voltage pulse and big initial current can be attributed to the coaxial cable.

关键词： surface modification ion implantation high voltage mode of