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Chinese Physics B 2008年第9期17卷 3464-3470页

作者：陈永生汪建华卢景霄郑文谷锦华杨仕娥郜小勇郭学军赵尚丽高哲 Institute of Plasma Physics Chinese Academy of Sciences Key Laboratory of Material Physics Department of PhysicsZhengzhou University Department of Materials Science and Engineering Wuhan Institute of Technology

This paper reports that the intrinsic microcrystalline silicon （μc-Si：H） films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200℃ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88 nm/s is obtained by using a plasma excitation frequency of 75 MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with H2 prior to plasma ignition, and selecting proper discharging time after silane flow injection. Material prepared under these conditions at a deposition rate of 0.78nm/s maintains higher crystallinity and fine electronic properties. By H-plasma treatment before i-layer deposition, single junction μc-Si：H solar cells with 5.5% efficiency are fabricated.

关键词： chemical vapour deposition plasma deposition solar cells crystallinity

Synthesis of few layer single crystal graphene grains on platinum by chemical vapour deposition

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Progress in Natural Science:Materials International 2015年第4期25卷 291-299页

作者： S.Karamat S.Sonu?en ü.?elik Y.Uysall? E.?zg?nül A.Oral Department of Physics Middle East Technical University COMSATS Institute of Information Technology Faculty of Engineering and Natural Sciences Sabanc? University Nano Magnetics Instruments Ltd.

The present competition of graphene electronics demands an ef fi cient route which produces high quality and large area graphene. chemical vapour deposition technique, where hydrocarbons dissociate in to active carbon species and form graphene layer on the desired metal catalyst via nucleation is considered as the most suitable method. In this study, single layer graphene with the presence of few layer single crystal graphene grains were grown on Pt foil via chemical vapour deposition. The higher growth temperature changes the surface morphology of the Pt foil so a delicate process of hydrogen bubbling was used to peel off graphene from Pt foil samples with the mechanical support of photoresist and further transferred to Si O2/Si substrates for analysis. Optical microscopy of the graphene transferred samples showed the regions of single layer along with different oriented graphene domains. Two type of interlayer stacking sequences, Bernal and twisted, were observed in the graphene *** presence of different stacking sequences in the graphene layers in fl uence the electronic and optical properties; in Bernal stacking the band gap can be tunable and in twisted stacking the overall sheet resistance can be reduced. Grain boundaries of Pt provides low energy sites to the carbon species, therefore the nucleation of grains are more at the boundaries. The stacking order and the number of layers in grains were seen more clearly with scanning electron microscopy. Raman spectroscopy showed high quality graphene samples due to very small D peak. 2D Raman peak for single layer graphene showed full width half maximum(FWHM) value of 30 cm-1. At points A, B and C, Bernal stacked grain showed FWHM values of 51.22, 58.45 and 64.72 cm-1, while twisted stacked grain showed the FWHM values of 27.26, 28.83 and 20.99 cm-1,respectively. FWHM values of 2D peak of Bernal stacked grain showed an increase of 20–30 cm-1 as compare to single layer graphene which showed its dispersive natu

关键词： chemical vapour deposition Graphene hexagonal crystals Bernal stacking Twisted stacking Grain boundaries and hydrogen bubbling

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Characterization of GaSb Films by Metalorganic chemical vapour deposition

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Rare Metals 1997年第3期16卷 68-72页

作者：李树玮张宝林金亿鑫周天明蒋红宁永强中科院长春物理所吉林长春

GaSb epilayers were grown on GaSb and GaAs substrates by atmospheric pressure metalorganic chemical vapor deposition (MOCVD). The properties of GaSb layers were characterized by low temperature photoluminescence (PL) spectra and scanning electron acoustic microscopy (SEAM) images. The temperature dependence of the PL spectrum was investigated and a red shift of bound excitons was observed in high quality epilayer. The pyramids of the surface and the buried subsurfaces were observed by scanning electron microscopy (SEM) and scanning electron acoustic microscopy (SEAM), and their growth model was discussed.

关键词： Semiconductors chemical vapour deposition Luminescence Surface and interface state

Growth of aligned single-walled carbon nanotubes under ac electric fields through floating catalyst chemical vapour deposition

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Chinese Physics B 2005年第10期14卷 2068-2076页

作者：窦新元周振平谭平恒周建军宋礼孙连峰江鹏刘利峰赵小伟罗述东张增星刘东方王健雄高燕周维亚王刚 Institute of Physics Chinese Academy of Sciences Beijing 100080 China State Key Laboratory for Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

Through floating catalyst chemical vapour deposition（CVD） method, well-aligned isolated single-walled carbon nanotubes （SWCNTs） and their bundles were deposited on the metal electrodes patterned on the SiO2/Si surface under ac electric fields at relatively low temperature（280℃）. It was indicated that SWCNTs were effectively aligned under ac electric fields after they had just grown in the furnace. The time for a SWCNT to be aligned in the electric field and the effect of gas flow were estimated. Polarized Raman scattering was performed to characterize the aligned structure of SWCNTs. This method would be very useful for the controlled fabrication and preparation of SWCNTs in practical applications.

关键词： carbon nanotube chemical vapour deposition

Electron behaviour in CH4／H2 gas mixture in electron-assisted chemical vapour deposition

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Chinese Physics B 2004年第10期13卷 1597-1600页

作者：董丽芳马博琴王志军 CollegeofPhysicsScienceandTechnology HebeiUniversityBaoding071002China

The behaviour of electrons in CH4/H2 gas mixture in electron-assisted chemical vapour deposition of diamond is investigated using Monte Carlo simulation. The electron drift velocity in gas mixture is obtained over a wide range of E/P (the ratio of the electric field to gas pressure) from 1500 to 300000 (V/m kPa?1). The electron energy distribution and average energy under different gas pressure (0.1–20kPa) and CH4 concentration (0.5%–10.0%) are calculated. Their effects on the diamond growth are also discussed. It is believed that these results will be helpful to the selection of optimum experimental conditions for high quality diamond film deposition.

关键词： Monte Carlo simulation chemical vapour deposition electron swarm drift velocity

Formation and photoluminescence properties of boron nanocones

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Chinese Physics B 2008年第10期17卷 3827-3835页

作者：王兴军田继发鲍丽宏杨天中惠超刘飞申承民许宁生高鸿钧 Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences State Key Laboratory of Optoelectronic Materials and Technologies School of Physics and EngineeringSun Yat-sen University

This paper reports that a simple chemical vapour deposition method has been adopted to fabricate large scale, high density boron nanocones with thermal evaporation of B/B2O3 powders precursors in an Ar/H2 gas mixture at the synthesis temperature of 1000-1200℃. The lengths of boron nanocones are several micrometres, and the diameters of nanocone tops are in a range of 50-100 nm. transmission electron microscopy and selected area electron diffraction indicate that the nanocones are single crystalline α-tetragonal boron. The vapour liquid solid mechanism is the main formation mechanism of boron nanocones. One broad photolumineseence emission peak at the central wavelength of about 650 nm is observed under the 532 nm light excitation. Boron nanocones with good photoluminescence properties are promising candidates for applications in optical emitting devices.

关键词： boron nanocones chemical vapour deposition photoluminescence

Multiple enlarged growth of single crystal diamond by MPCVD with PCD-rimless top surface

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Chinese Physics B 2019年第12期28卷 352-357页

作者： Ze-Yang Ren Jun Liu Kai Su Jin-Feng Zhang Jin-Cheng Zhang Sheng-Rui Xu Yue Hao State Key Discipline Laboratory of Wide Band-Gap Semiconductor Technology School of MicroelectronicsXidian UniversityXi'an 710071China

We report the simultaneous enlarged growth of seven single crystal diamond(SCD) plates free from polycrystalline diamond(PCD) rim by using a microwave plasma chemical vapor deposition(MPCVD) system. Optical microscope and atomic force microscope(AFM) show the typical step-bunching SCD morphology at the center, edge, and corner of the samples. The most aggressively expanding sample shows a top surface area three times of that of the substrate. The effective surface expanding is attributed to the utilization of the diamond substrates with(001) side surfaces, the spacial isolation of them to allow the sample surface expanding, and the adoption of the reported pocket holder. Nearly constant temperature of the diamond surfaces is maintained during growth by only decreasing the sample height, and thus all the other growth parameters can be kept unchanged to achieve high quality SCDs. The SCDs have little stress as shown by the Raman spectra. The full width at half maximum(FWHM) data of both the Raman characteristic peak and(004) x-ray rocking curve of the samples are at the same level as those of the standard CVD SCD from Element Six Ltd. The nonuniformity of the sample thickness or growth rate is observed, and photoluminescence spectra show that the nitrogen impurity increases with increasing growth rate. It is found that the reduction of the methane ratio in the sources gas flow from 5% to 3% leads to decrease of the vertical growth rate and increase of the lateral growth rate. This is beneficial to expand the top surface and improve the thickness uniformity of the samples. At last, the convenience of the growth method transferring to massive production has also been demonstrated by the successful simultaneous enlarged growth of 14 SCD samples.

关键词： diamond chemical vapour deposition crystal growth expanded top surface polycrystalline diamond rimless

Electrical Properties of Plasma Deposited Low-Dielectric-Constant Fluorinated Amorphous Carbon Films

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Plasma Science and Technology 2006年第6期8卷 724-726页

作者：吴振宇杨银堂汪家友 Key Lab of Ministry of Education for Band-Gap Semiconductor Materials and Devices Institute of MicroelectronicsXidian UniversityXi'an 710071China

Fluorinated amorphous carbon （a-C：F） films were deposited at room temperature using C4Fs and CH4 as precursor gases by electron cyclotron resonance chemical vapour deposition （ECR-CVD）. chemical structures were analysed using X-ray photoelectron spectroscopy （XPS）. The current conduction shows ohmic behaviour and the leakage current increases with the content of C sp2 in the deposited a-C：F films at a low electric field. The behaviour of the leakage current is well e^plained by the Poole-Frankel mechanism at a high electric field. The interface traps, rather than chemical structures, of a-C：F films determine the PF emission current.

关键词： electrical properties conduction behaviour chemical vapour deposition a-C:F

Nanotube-Based chemical and Biomolecular Sensors

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Journal of Materials Science & Technology 2008年第4期24卷 578-588页

作者： J.Koh B.Kim S.Hong H.Lim H.C.Choi Department of Physics and Astronomy Seoul National University Shillim-Dong Kwanak-Gu Seoul 151-747 Korea Department of Chemistry Pohang University of Science and Technology San 31 Hyoja-Dong Nam-Gu Pohang 790-784 Korea

We present a brief review about recent results regarding carbon nanotube （CNT）-based chemical and biomolecular sensors. For the fabrication of CNT-based sensors, devices containing CNT channels between two metal electrodes are first fabricated usually via chemical vapor deposition （CVD） process or ＂surface programmed assembly＂ method. Then, the CNT surfaces are often functionalized to enhance the selectivity of the sensors. Using this process, highly-sensitive CNT-based sensors can be fabricated for the selective detection of various chemical and biological molecules such as hydrogen, ammonia, carbon monoxide, chlorine gas, DNA, glucose, alcohol, and proteins.

关键词： chemical vapour deposition Carbon nanotubes Sensors Biological molecules Surface programmed assembly

Graphene/SrTiO3 hetero interface studied by X-ray photoelectron spectroscopy

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Progress in Natural Science:Materials International 2016年第4期26卷 422-426页

作者： S.Karamat C.Ke U.Y.Inkaya Rizwan Akram Ilker Yildiz S.Shah Zaman A.Oral Department of Physics Middle East Technical University COMSATS Institute of Information Technology Microelectronics Centre School of Electrical and Electronic Engineering Nanyang Technological University Department of Electrical Engineering College of Engineering Qassim University

The present paper focuses on study of graphene and strontium titanate（SrTiO3or STO） interface. An ambient pressure chemical vapour deposition（AP-CVD） setup is used to grow graphene on STO（110）substrates in the presence of methane, argon and hydrogen gases at 1000 °C for 4 h. Raman spectroscopy measurements confirm the presence of graphene on STO substrates due to the existence of typical D and G peaks referring to graphene. These characteristic peaks are missing in the spectrum for bare substrates.X-ray photoelectron spectroscopy（XPS） is carried out for elemental analysis of samples, and study their bonding with STO substrates. We employed the valence band spectrum to calculate the valence band offset（VBO） and conduction band offset（CBO） at the G-STO interface. Also, we present an energy band diagram for Bi-layer and ABC（arranging pattern of carbon layers） stacked graphene layers.

关键词： chemical vapour deposition X-ray photoelectron spectroscopy Raman spectroscopy Graphene Valence band maximum