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oe1(光电查) - 科学论文

35 条数据
?? 中文(中国)
  • Correlation of acetylene plasma discharge environment and the optical and electronic properties of the hydrogenated amorphous carbon films

    摘要: Thin films from polymeric and graphitic hydrogenated amorphous carbon (a-C:H) were deposited over a glass substrate from acetylene (C2H2) plasma by using a conventional plasma enhanced chemical vapor deposition (PECVD). Radio frequency capacitively coupled plasma (RF CCP) source operating at a frequency of 13.56 MHz was used for generation of the discharge. Optical emission spectroscopy (OES) results showed strong optical emissions from diacetylene ion C4H2+ at a wavelength of 506 nm. The energy dispersive X-Ray (EDS) measurements illustrated that the carbon content in the deposited films increased with increasing of power. The Raman and IR results demonstrated that the films deposited at low bias voltages 340 V are so called polymeric a-C:H with high sp3 fraction and high hydrogen content, while the films deposited at high bias voltages 877 V are so called graphitic a-C:H with low sp3 fraction and low hydrogen content. Quantitative information were obtained from fitting the high asymmetrical vibrational modes of Raman and IR spectra by using Fano model expression together with Lorentzian function. The results presented here point out that there is a relation between the intensity of C4H2+ ion emissions and the deposited films properties.

    关键词: Optical Emission,diacetylene ion,RF CCP,Hydrogenated amorphous carbon,FTIR,Raman spectroscopy

    更新于2025-11-14 15:30:11

  • Modular Ceramic-Polymeric Device for Analysis of Selected Elements in Liquid Using Microplasma

    摘要: Miniaturization of devices for analysis of chemical composition is being still developed. In this article we present a portable device with a microplasma excitation source. The microdischarge is ignited inside a ceramic structure between a solid anode and a liquid cathode. As a result of cathode sputtering of the solution, it is possible to determine its chemical specimens by analysis of emission spectra of the microdischarge. We fabricated cathodes with a microfluidic compartment and two types of anodes. Devices were tested experimentally. Spectroscopic properties of the microdischarge and its analytical performance depended on the used ceramic structure, the surface area of the cathode aperture and the flow rate of the solution.

    关键词: optical emission spectroscopy,microplasma,LTCC

    更新于2025-09-23 15:23:52

  • Gas Breakdown and Discharge Formation in High-Power Impulse Magnetron Sputtering

    摘要: Discharge behaviors of high-power impulse magnetron sputtering with different targets have been investigated. Distinct current–voltage curves and target current waveforms are observed. Breakdown voltage and the maximum target current show a periodic drop with the increase of atomic number in subgroups and periods. The target current density is found to be mainly affected by the secondary electron emission yield. Thus, its magnitude is unable to directly evaluate the ionization degree of sputtered atoms in high-power impulse magnetron sputtering (HiPIMS) process. In this paper, the interactive influence of secondary electron emission, sputter yield, and ionization energy on the ionization degree of sputtered atoms is discussed based on the analysis of the voltage and current characteristics. As a result, targets can be categorized into three sorts according to the ionization degree: 1) low ionization degree targets, such as Ag and C less than 10%; 2) intermediate ionization degree targets like Cr and Cu with 55% and 35%; 3) Ti, Zr, and Mo targets with the second ionization processes. These results provide institutive operation ranges for the state-of-the-art HiPIMS applications.

    关键词: optical emission spectroscopy (OES),ionization degree,Current waveform,gas breakdown,high-power impulse magnetron sputtering (HiPIMS)

    更新于2025-09-23 15:22:29

  • Spectroscopic Studies of Magnetron Sputtering Plasma Discharge in Cu/O2/Ar Mixture for Copper Oxide Thin Film Fabrication

    摘要: Magnetron sputtering plasma for the deposition of copper oxide thin film has been investigated using optical emission spectroscopy and Langmuir probe. The intensity of the light emission from atoms and radicals in the plasma were measured using optical emission spectroscopy (OES). Then, Langmuir probe was employed to estimate the plasma density, electron temperature and ion flux. In present studies, reactive copper sputtering plasmas were produced at different oxygen flow rate of 0, 4, 8 and 16 sccm. The size of copper target was 3 inches. The dissipation rf power, Ar flow rate and working pressure were fixed at 400 W, 50 sccm and 22.5 mTorr, respectively. Since the substrate bias plays an important role to the thin film formation, the substrate bias voltages of 0, -40, -60 and -100 V were studied. Based on OES results, oxygen emission increased drastically when the oxygen flow rate above 8 sccm. On the other hand, copper and argon emission decreased gradually. In addition, Langmuir probe results showed a different ion flux when substrate bias voltage was applied. Based on these plasma diagnostic results, it has been concluded that the optimized parameter to produce copper oxide thin film are between -40 to -60 V of substrate bias voltage and between 8 to 12 sccm of oxygen flow rate.

    关键词: optical emission spectroscopy,Langmuir probe,thin film,magnetron sputtering,Copper oxide

    更新于2025-09-23 15:22:29

  • 3D spectroscopic measurement of argon and metal vapour in MIG welding

    摘要: Spectroscopic measurements for gas-metal arc (GMA) phenomena have been recently performed. The studies have reported that the metal vapour behaviour greatly affects the arc properties. However, they can be applied only to axially symmetric phenomena because of the assumption used for the measurement. GMA welding are normally performed with a travel speed, and most of the phenomena become axially asymmetric. This study constructed the simultaneous and multidirectional measurement system by 12 CCD cameras which can capture such axially asymmetric GMA phenomena. We measured the metal inert gas welding process with use of two types of narrowband interference filters for Ar I and Fe I during the one measurement, and observed axially asymmetrical intensity distributions in the globular and the spray transfer mode. We found that the globular transfer mode that is seemingly chaotic distribution can be regarded as the distribution where the deviation of Ar I is larger than Fe I from the axially symmetric double-ring distribution that consists of Ar I and Fe I.

    关键词: image reconstruction,ML-EM method,CCD camera,globular transfer,interference filter,axially asymmetrical arc plasma,spray transfer,Optical emission spectroscopy

    更新于2025-09-23 15:21:21

  • Hanging drop cathode-atmospheric pressure glow discharge as a new method of sample introduction for inductively coupled plasma-optical emission spectrometry

    摘要: This work reports the use of hanging drop cathode-atmospheric pressure glow discharge (HDC-APGD) as a new method of sample introduction for inductively coupled plasma-optical emission spectrometry (ICP-OES). The developed arrangement was characterized by a low sample uptake (0.56 mL min?1) and the fact that the entire sample solution volume was consumed by the discharge. This resulted in a very high transport efficiency of analytes from the sample solution into the ICP torch (usually > 80%). Under the optimal operating conditions of HDC-APGD, intensities of emission lines of studied elements were, on average, 2 times higher as compared to those obtained with conventional pneumatic nebulization (PN). Moreover, in the case of I and Y, the observed signal enhancements were even higher, i.e., 6.2 and 6.1 times, respectively. It was also shown that in the case of B and some elements that are known to form different volatile species (Ag, Bi, Cd, Hg, Os, Pb, and Se), the presence of low molecular weight organic compounds in the sample solution, i.e., CH3OH, C2H5OH, HCOOH, CH3COOH, or HCHO, resulted in the additional enhancement of their signals. It was especially evident in the case of Hg for which a 8.6-fold signal enhancement in the presence of HCOOH was noticed. The system presented herein was distinguished from other competitive APGD-type discharges because it could be successfully used for the determination of a vast group of elements, including alkali metals, alkaline earth metals, transition metals, and non-metals.

    关键词: Atmospheric pressure glow discharge,Hanging drop cathode,Inductively coupled plasma,Optical emission spectrometry,Sample introduction

    更新于2025-09-23 15:21:01

  • Time-resolved optical characterization of the interaction between a laser produced plasma and a spark discharge

    摘要: The interaction between a nanosecond laser produced plasma and a unipolar high voltage discharge was analyzed using time-resolved spectroscopy, fast photography with narrow band interference filters and profilometry. Here the laser ablation fluence was varied in the 60–1000 J/cm2 range. The 600-kW electrical discharge was triggered by an ablation plasma on the aluminum target at time 700 ns in order to enhance the laser-induced breakdown spectroscopy (LIBS) emission. Most of the spectra were obtained from a spot 1 mm above the target and these were: time-integrated to gauge overall enhancement and time-resolved to investigate emission enhancement, temperature and density as a function of time. It was found that the time-and-space integrated LIBS signal was enhanced by up to one order of magnitude at the lowest laser fluence employed when compared with a conventional LIBS experiment. Also, that this emission increment could not be mainly attributed to an increased mass removal, but rather to an enhancement of plasma ionization degree as was observed by means of fast photography with filters. This causes longer plasma duration and more enhancement of ionic species than neutrals. It was also found that both the electronic density and the temperature increase when the spark discharge is applied, in comparison with the ablation plasma. Emission enhancement is inversely proportional to laser fluence due to the fact that for higher fluences, by the time the discharge is applied, the laser-produced plasma is already highly excited.

    关键词: LIBS,Spark discharge,Optical emission spectroscopy,Plume dynamics,Fast photography

    更新于2025-09-23 15:21:01

  • Effect of Ga introduction during the second stage of a coevaporation process of Cu(In,Ga)Se2 layers at low temperature on polyimide substrates

    摘要: A proper control of Ga concentration pro?le is mandatory to achieve high e?ciency Cu(In,Ga)Se2 (CIGS) solar cells. At low temperature, deep gradients, detrimental for carriers' di?usion, are obtained when CIGS is deposited with a standard three-stage process: an optimization of the process is needed. In this study, we show the impact of a modify three-stage process on the depth of the notch by introducing Ga ?ux during the second stage from 0 nm/min to 1.1 nm/min. A higher open circuit voltage compensated by a lower short current density is obtained due to higher band gap energy. The surface and the bulk of the CIGS layer was analyzed at the end of the second stage by coupling di?erent characterization techniques: glow discharge optical emission spectroscopy, Raman and X-ray photoelectrons spectroscopy. The presence of binary compounds as well as a Ga enrichment at the end of the second stage are observed when Ga is introduced during the second stage.

    关键词: low temperature,X-ray photoelectron spectroscopy,solar cells,Cu(In,Ga)Se2,three-stage process,glow discharge optical emission spectroscopy,Raman spectroscopy,CIGS,Ga concentration pro?le

    更新于2025-09-23 15:21:01

  • Characteristics of laser induced discharge tin plasma and its extreme ultraviolet radiation

    摘要: In this paper, a CO2 laser induced discharge plasma extreme ultraviolet (EUV) source experimental device was established. The optical emission spectroscopy was used to diagnose the characteristics of the plasma, and the evolution of electron temperature and electron density with time was obtained. The in?uence of discharge voltage on plasma parameters was analyzed and discussed. The EUV radiation characteristics of the plasma were investigated by self-made grazing incidence EUV spectrometer. The EUV radiation intensity and conversion ef?ciency were discussed.

    关键词: laser induced discharge plasma,extreme ultraviolet (EUV) radiation,electron temperature and density,optical emission spectroscopy

    更新于2025-09-23 15:19:57

  • Simple Universal Strategy for Quantification of Carboxyl Groups on Carbon Nanomaterials: Carbon Dioxide Vapor Generation Coupled to Microplasma for Optical Emission Spectrometric Detection

    摘要: The physicochemical properties and applications of carbon nanomaterials are remarkably dependent on the amount of carboxyl group on their surfaces. Unfortunately, it is challenging to determine the carboxyl group on carbon nanomaterials at an ultralow density not only due to the low sensitivities of conventional techniques, but also because there are no matrix-matched certi?ed reference materials available. In this work, a novel strategy comprising coupling carbon dioxide vapor generation to a microplasma optical emission spectrometer was developed for the sensitive and accurate quanti?cation of surface carboxyl groups on carbon nanomaterials. The carboxyl group on multiwall carbon nanotubes (MWCNTs), graphene (G), or its oxide (GO) was converted to carboxylic acid using concentrated hydrochloric acid prior to quanti?cation. The generated carboxylic acid was puri?ed and then reacted with sodium bicarbonate to generate CO2, which was swept into a miniaturized point discharge optical emission spectrometer (μPD-OES) for the detection of carbon atomic emission lines. Potassium hydrogen phthalate (KHP) served as a calibration standard for quanti?cation of the carboxyl group on G/GO/MWCNTs, thus, overcoming the lack of CRMs. Owing to the high sensitivity of μPD-OES for the detection of CO2, a limit of detection of 0.1 μmol g?1 (1 nmol) was obtained for the carboxyl group based on a sample mass of 10 mg G/GO/MWCNTs, superior to that obtained using conventional methods. Moreover, the proposed method not only retains several unique advantages of good accuracy and elimination of the use of complicated, expensive, and high power-consumption instruments, but was also applicable to the quanti?cation of the carboxyl group on other nanomaterials such as carboxylated magnetic microspheres.

    关键词: carbon dioxide vapor generation,microplasma optical emission spectrometer,carbon nanomaterials,quantification,carboxyl groups

    更新于2025-09-23 15:19:57