摘要
本文探索了一种平板式小孔电极的放电装置,采用电学测量,光学诊断等方法对射频容性氩等离子体进行了研究。
在一定的条件下,特别放电气压条件适当时,两种放电模式可以共存,其物理原因是两种放电模式的维持电压在不同气压下相对大小不同。大气压下,α模式的维持电压高于γ模式,导致一旦放电电压超过γ模式的维持电压,放电将完全转变为γ模式,形成局部丝状微弧放电。对于氩气的大气压射频放电特性实验研究发现:可以实现两个模式在大气压放电条件下的共存。本文中,我们首先实现了大气压条件下的氩气流动体系中容性射频放电的α和γ两个模式及其转变与共存,对放电形态进行了观察,利用伏安特性进行分析,确认了两种模式的产生和共存。
由于放电处于开放大气环境中,放电发射光谱中清晰地存在N2 C3∏u→B3∏g跃迁产生的第二正带和OH自由基A2∑→X2∏跃迁的(0,0)带光谱。为了获得放电区域的宏观温度,针对氮的第二正带(0,1),(1,2)两个谱带,自编了拟合程序,用温度拟合方法获得了氮分子的转动温度和振动温度,研究了转动温度随放电功率的变化趋势,得到了温度突变与放电模式转变的相关性。利用Lifbase的发射光谱模拟功能,进行了OH自由基A2∑→X2∏(0,0)带光谱的模拟,通过与实验光谱对比,得到了与N2光谱拟合结果相符的OH转动温度,以及相似的随放电功率的变化趋势,这说明放电空间内的中性物种达到了热平衡状态。放电模式转变对应的转动温度变化趋势根据放电伏安特性变化得到确认,并且与放电形态的照片符合。用波尔兹曼曲线的方法测得了氩原子的激发温度,而且激发温度并不随功率的改变有明显的改变,约为2800K,并估算了电子温度。
探索了用红外热像仪的测量气体温度的方法,对红外热像仪的测量原理做了简要的介绍,并用红外热像仪的方法测量了放电的宏观温度,与光谱测得的转动温度相吻合。
In this paper, the characteristics of RF argon capacitive discharge at atmospheric pressure with the structure of fiat-plate electrodes are investigated by electrical measurements and optical diagnostics.
The existence of two discharge modes named a and y mode were found under specific conditions, the holding voltage of two discharge modes are different in different gas pressure. The holding voltage of a mode is higher than the holding voltage of y mode in atmospheric pressure. So a mode to y mode transition at higher voltage will be investigated. The mode transition and coexistence were found in atmospheric pressure argon RF capacitive discharge. In this paper, according to the change of Current-voltage characteristics, the mode transition was affirmed, and answered to the photograph of discharge.
The emission spectra of N2 (C3Πu→B3Πg) and OH (A2Σ→X2Π) were observed due to the atmosphere surrounding. By use of a program compiled by the authors for the nitrogen's second positive band simulation, comparison between the experimental and simulated spectra of band (0,1), (1,2) was used to determine the rotational and vibrational temperature of N2. The trend of vibrational and rotational temperature with discharge power was studied to observe the temperature jump corresponding to the discharge mode transition. Utilizing a well-known software named Lifbase, the simulated spectra of OH (A-X) (0,0) was calculated to obtain the rotational temperature of OH by comparing with the experimental OH (A-X) (0, 0) band. The resultant rotational temperature of OH is well consistent with the result of nitrogen's second positive band, which shows that the neutral species are at thermal equilibrium in the space of discharge. Excited temperature was about 2800K attained by Boltzmann equation, and excited temperature not evidently changes versus the change of power. Electron temperature was estimated on the basis of excited temperature.
The theory of infrared thermal imager was introduced. Gas temperature was measured using infrared thermal image, and answered to rotational temperature.
引文
[1]迈克尔.A.力伯曼.等离子体放电原理与材料处理[M].北京:科学出版社,2007.
[2]F.F.Chen. PRINCIPLES OF PLASMA PROCESSING[M]. Plenum/Kluwer Publishers,2002.
[3]徐学基.气体放电物理[M].上海:复旦大学出版社,1996.
[4]F. Iza, G. J. Kim, and S. M. Lee. Microplasmas:Sources, Particle Kinetics, and Biomedical Applications[J]. Plasma Proc. Polym,2008,5(4):322-344.
[5]K.H.Becker, K.H.Schoenbach, and J.G.Eden. Microplasmas and applications[J]. J. Phys. D:Appl. Phys,2006,39:R55-R70.
[6]R. Foest.M. Schmidt, and K. Becket. Microplasmas, an emerging field of low-temperature plasma science and technology[J]. Int. J. Mass Spectrom,2005,248(3):87-102.
[7]R. Foest, M.Schmidt, and K. Becket. Microplasmas, an emerging field of low-temperature plasma science and technology[J]. Int. J. Mass Spectrom,2005,248(3):87-102.
[8]Engle A V, Seeliger R, Steenback M. On the glow dischargeat high pressure[M]. Zeit. fur Physik.,1933,85:144-160.
[9]Kanazawa S, KogomaM, Moriwaki T et al. Stable glow plasma at atmospheric pressure[J]. J Phys D:Appl Phys,1988,21(5):838-840.
[10]0kazaki S J, Kogoma M, Uehara M, Kimura Y. Appearance od stable glow discharge in air, argon, oxygen and nitrogen at atmospheric pressure using 50 Hz source [J]. Journal of Applled Physics,1993,26:889-892.
[11]Massines F et al. Experimental and theoretical study of a glow discharge at atmospheric pressure controlled by dielectric barrier[J]. Appl Phys,1998,83:2950.
[l2]Gadri R B et al. An overview of the physical processes, phenomenology, and applications of the one atmosphere uniform glow discharge plasma(OAUGDPTM). First International Symposium medical/biological treatments Using electromagnetic field and ionized gas[C]. norfolk, VA. USA,1999, G-5:12.
[13]J.R.罗思.工业等离子体工程[M].北京:科学出版社,1998.
[14]L. F. Dong, F. C. Liu, and S. H. Liu et al. Observation of spiral pattern and spiral defect chaos in dielectric barrier discharge in argon/air at atmospheric pressure [J]. Phys. Rev. E,2005,72:046215,1-8.
[15]M. Klein, N. Miller, and M. Walhout. Time-resolved imaging of spatiotemporal patterns in a one-dimensional dielectric-barrier discharge sy stem [J]. Phys. Rev. E,2001,64:026402.1-5.
[16]Morrow R. Theory of negative corona in oxygen [J]. Phys. Rev. A,1985,32(3):1799-1809.
[17]R. J. Van Brunt. Stochastic properties of partial-discharge phenomena[J]. IEEE Trans. Electr. Insulation,1991,26(5):902-948.
[18]A. P. Napartovich, Y. S. hkishev, A. A. Deryugin, et al. A numerical simulation of Trichel-pulse formation in a negative corona[J]. J. Phys. D:appl. Phys,1997, 30(19):2726-2736.
[19]科罗拉实验室.低温等离子体[EB].http://www. coronalab. net/coldplasm/coldplasm. htm
[20]Park J, Henins I, Herrmann H W et al. Discharge phenomena of all atmospheric pressure radio-frequency capacitive plasma source[J]. J. Appl. Phys.,2001,89(1):20-28.
[21]T Ito, T Izaki, K Terashema. Application of microscale plasma to material processing[J]. Thin Solid Film,2001,386(2):300-304.
[22]S. E. Alexandrov, M. L. Hitchman. Enhanced by Atmospheric Pressure Non-thermal Non-equilibrium Plasmas[J]. Chemical Vapor Deposition,2005,11:457-468.
[23]Nowling G R, Babayan S E, Jankovic V and Hicks R F. Remote plasma-enhanced chemical vapour deposition of silicon nitride at atmospheric pressure[J]. Plasma Sources Science and Technology,2002,11:97-103.
[24]Yokotani A et al. Analysis of the Photochemical Reaction on the Surface for Room Temperature Deposition of SiO2 Thin Fiires by Photo-CVD using Vacuum Ultraviolet Light[J]. Japanese Journal of Applied Physics,2005,44:1019-1021.
[25]Pant A, Russell T W F et al. Hot-Wire Chemical Vapor Deposition of Silicon from Silane: Effect of Process Conditions[J]. Ind. Eng. Chem. Res.2001,40,1377-1385.
[26]Kubart T, Depla D, Martin D M, Nyberg T. Berg S. High rate reactive magnetron sputter deposition of titanium oxide[J]. Appl. Phys. Lett.2008,92,1501.
[27]Sarra-Bournet C, Turgeon S, Mantovani D, and Laroche G. Comparison of atmospheric-pressure plasma versus low-pressure RF plasma for surface functionalization of PTFE for biomedical applications[J]. Plasma Processes and Polymers,2006,3:506-515.
[28]Ladwig A, Babayan S, Smith M, Hester M, Highland W, Koch R, and Hicks R. Atmospheric plasma deposition of glass coatings on aluminum[J]. Surface and Coatings Technology,2007, 201:6460-6464.
[29]Leveille V, Coulombe S. Electrical probe calibration and power calculation for a miniature 13.56 MHz plasma source[J]. Measurement Science and Technology,2006,17: 3027-3032.
[30]Shi J J, Kong M G. Mechanisms of the a and g modes in radio-frequency atmospheric glow discharges[J]. Journal of Applied Physics,2005,97:023306.
[31]Moon S Y, Rhee J K, Kim D B, Gweon B M, Choe W. Capacitive discharge mode transition in moderate and atmospheric pressure[J]. Current Applied Physics,2009,9:274-7.
[32]Dieter M Zube, Monika Auweter-Kurtz.29th Joint Propulsion Conference and Exhibit Monterey [C]. CA. USA, J une. AIAA,1993.1792.
[33]Zhao Wen-hua, Li Jian-quan, YANGJ D, et al. Temperature measurement of nonsteady arcs[J]. IEEE Transactions on Plasma Science,1997,25 (5):828-832.
[34]Huber K P, Herzberg G. Molecular Spectra and Molecular Structure[M].1979,95.
[35]Schutze A., Jeong J. Y., Babayan S.E., Park J., Selwyn G.S., and Hicks R. F. The atmospheric-pressure plasma jet:A review and comparison to other plasma sources [J]. IEEE Transactions On Plasma Science,1998,26:1685-1694.
[36]吴蓉,李燕,朱顺官,冯红艳.等离子体电子温度的发射光谱法诊断[J].光谱学与光谱分析,2008,28(4):731-735.
[37]Budde W. Optical Radiation Measurements, Vol.4[M]. Physics Detectors of Optical Radiation, Academic Press,1983.
[38]Shi J J, Kong M G. Radio-frequency dielectric-barrier glow discharges in atmospheric argon[J]. Applied Physics Letters 2007,90:111502-1-3.
[39]Zhu W C, Wang B R, Yao Z X, Pu Y K. Discharge characteristics of an atmospheric pressure radio-frequency plasma jet[J]. J.Phys.D:Appl.Phys,2005,38:1396-1401.
[40]Park J, Henins I, Herrmann H W, Selwyn G S, Hicks R F. Discharge phenomena of an atmospheric pressure radio-frequency capacitive plasma source[J]. Journal of Applied Physics,2001,89:20-8.
[41]XinPei Lu, Frank Leipold and Mounir Laroussi. Optical and electrical diagnostics of a non-equilibrium air plasma[J]. J. Phys. D:Appl. Phys,2003,36:2662-2666.
[42]C O Laux, T G Spence, C H Kruger and R N Zare. Optical diagnostics of atmospheric pressure air plasmas[J]. Plasma Sources Sci. Technol,2003,12:125-138.
[43]0 Motret, C Hibert, S Pellerin and J M Pouvesle. Rotational temperature measurements in atmospheric pulsed dielectric barrier discharge-gas temperature and molecular fraction effects[J]. J. Phys. D:Appl. Phys,2000,33:1493-1498.
[44]M. BAZAVAN, I. IOVA. TEMPERATURE DETERMINATION OF A COLD N2 DISCHARGE PLASMA BY THE FIT OF THE EXPERIMENTAL SPECTRAWITH THE SIMULATED EMISSION SPECTRA[J]. Romanian Reports in Physics,2008,60(3):671-678.
[45]G Faure, S M Shkolnik. Determination of rotational and vibrational temperatures in a discharge with liquid non-metallic electrodes in air at atmospheric pressure[J]. J. Phys. D:Appl. Phys.1998,31:1212-1218.
[46]Piper L G. REEVALUATION OF THE TRANSITION-MOMENT FUNCTION AND EINSTEIN COEFFICIENTS FOR THE N2(A (3)SIGMA(U+)-X (1)SIGMA(G+)) TRANSITION[J]. Journal of Chemical Physics,1993,99:3174-3181.
[47]郝作强,张杰,俞进,张喆,仲佳勇.空气中激光等离子体通道导电性能的研究[J].物理学报,2006,55:299.
[48]Luque J, Crosley D R 1999 LIFBASE:Database and Spectral Simulation Program (Version 2.0.53)[CP], SRI International Report MP99-009.
[49]Dieter M Zube, Monika Auweter-Kurtz.29th Joint Propulsion Conference and Exhibit [C]. Monterey, CA, USA, June. AIAA,1993,1792.
[50]Chul Park. Hydrogen line ratios as electron temperature indicators in nonequilibrium plasmas[J]. Journal of Quantitative Spectroscopy and Radiative Transfer,1972,12:323-370.
[51]Hyung Jin Kim, Sang Hee Hong. Comparative measurements on thermal plasma jet characteristics in atmospheric and low pressure plasma sprayings [J]. IEEE Transactions on Plasma Science,1991,5(4):481-490.
[52]J. JONKERS and J. A. M. VAN DER MULLEN. THE EXCITATION TEMPERATURE IN (HELIUM) PLASMAS[J].J. Quant. Spectrosc. Radiat. Transfer,1999,61(5):703-709.
[53]姚学军,红外测温原理与测温技术[J],中国仪器仪表,1999,1:10-13.
[54]吴永红,夏德宏.气体热辐射机理的研究与热辐射特性的计算[J].热科学与技术,2003,2(4):342-346.
[55]王厚华.传热学[M].重庆:重庆大学出版,2006.
[56]赵振奇.冶金工厂除尘设备性能测定[M].北京:冶金工业出版社,1981.