微细加工技术 Application of Water- jet-guided Laser Technology in Micro-machining School of Mechanical Engineering Automation, Xihua University, Chengdu 610039, China) Abstract: Micro-machining of semiconductor based on water-jet-guided laser technology was studied and compared with conventional cutting process. When cutting 125 um GaAs, on the condition of $25 um water jet and ND-YAG laser with 1 064 nm wave length, the 323 times more than that of diamond sawing. Experiment indicates that the temperature of work piece is under 160C. No debris an burrs was found on the cutting surface of wafers. The experiment of 3-point bend also shows that at the same cutting width, the breakage strength for 125 um thick silicon wafer is more than 50%at both sides. The results show that micro-machining of semiconductor using water jet guided laser can greatly increase the product efficiency, improve surface quality and reliability of micro- apparatus. Therefore it has good market value and high benefit in the industries of semiconductor, microelectronics, wireless communication and other fields Key words: water-jet-guided laser: laser micro-jet; micro-machiningi dicing; semiconductor (上接第59页) e,2003,163:242-255 hen P Boyd,etal. Simple accurate expressions for planar[7]吴英,江永清周兆英,等.MRI微型RF接收线圈的设 EEE Journal of Solid-state 计与制作[].半导体光电,2006,27(5):556-559 Circuits,1999,34(10):1419-1424. [8] Sorli B, Chateaux J F, Pitaval M,et al. Micro-spectrometer 16] Massin C, Vincent F, Homsy A, et al. Planar microcoil- for NMR: analysis of small quantities in vitro[J]. Meas Sci based microfluidic NMR probes[J] Journal of Magneti Technol,2004,15:877-880 High-Q NMR Planar Microcoil Based on MEMS LI Xiao-nan,, WANG Ming, YANG Wen-hui, WANG Li, SoN( (1. Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, Chin 2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China; 3. Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China) Abstract: For increasing the Signal-to-Noise Ratio of Nuclear Magnetic Resonance experiment, detection for samples with nano-liter quantity and integration with microfluidic, the fabrication of planar microcoils with high Q value is presented. Based on the results of calculation for the simulation of SNR, several kinds of geometries of circular or square microcoils were fabricated on glass substrates using photolithography with SU-8 and DC copper electroplating. With the home-developed electroplating technology the growing speed of copper layer is 1.2 um/ min approximately. The geometries for the microcoils fabricated successfully are inner radius 200 um 000 um, width separation 20 pm-80 um, number of turns 1-9, wire thickness 12 um. Using agilent 4294 Impedance Anal the measured RF parameters for No 1000-1 Microcoil under 85 MHz/2 Tesla is RAC=7. 25 n, L= 285 nH, Q= 21. The trend of Q the Q value reaches maximum at 85 MHz In electroplating scheme, this process of fabrication is simple and only one step of electroplating is needed. As a result the parasitic capacitance of shorted leaders of microcoil is decreased remarkable while increasing Q value. More important, compared with solenoid, in micron level the fabrication of planar microcoil is more compatible with MEMS. This work is an important step towards the integration of Nmr detection into micro-total analysis systems (uTAs) Key words: NMR planar microcoil; signal-to-noise radio; MEMS; copper electroplating微 细 加 工 技 术 2008伍 ApplicationofWater-jet-guidedLaserTechnologyinMicro-machining CAILi—ming，LEIYu—yong，BINGLong—jian，TANGLing—bo (SchoolofMechanicalEngineering& Automation，XihuaUniversity，Chengdu610039，China) Abstract：Micro—machiningofsemiconductorbasedonwater-jet—guidedlasertechnologywas studiedandcomparedwithconventional cuttingprocess．Whencutting,~125 mGaAs，ontheconditionofq,25 m waterjetandND·YAGlaserwith1064nmwavelength，the typicalcuttingspeedis40 mm／sandthecuttingwidth is23“m．No damage to thecuttingedge wasfound．Thecuttingspeed is5 timesmorethanthatofdiamond sawing．Experimentindicatesthatthetemperatureofwork pieceisunder 160 oC ．Nodebrisand burrswasfound on the cutting surface ofwafers． The experimentof3-pointbend also shows thatatthesame cutting width，the breakagestrength for 125 ／zm thick silicon waferis more than 50％ atboth sides． The resuhs show thatmicro—machining of semiconductorusingwaterjetguidedlasercangreatlyincreasetheproductefficiency，improvesurfacequalityandreliabilityofmicro— apparatu~ Therefore it has good market value and high benefit in the industries of semiconductor，mieroelec tronics，wireless communicationandotherfields． Keywords：water-jet--guidedlaser；lasermicro-jet；micro--machining；dicing；semiconductor (上接第 59页) hen P Boyd，eta1 ．Simpleaccurateexpressionsforplanar spiralinductances[J]． IEEE Journal of Solid—state Circuits，1999，34(10)：1419—1424． [6] MassinC，VincentF，HomsyA，eta1．Planarmicrocoil￾basedmicrofluidicNMR probeslJJ．Journal ofMagnetic [7] [8] Resonance，2003，l63：242—255． 吴英，江永清 ，周兆英 ，等 ．MRI微型 RF接收线圈的设 计与制作[J]．半导体光电，2006，27(5)：556—559． SorliB，ChateauxJF，Pitaval M ，eta1 ．Micro—spectrometer forNMR：analysisofsmallquantitiesinvitrolJj．MeasSci Technol，2004，15：877—880． High-Q NMRPlanarMicrocoilBasedonMEMS LIXiao—nan ，W ANG Ming ，YANG W en—hui，W ANG Li，SONG Tao (1．InstituteofElectricalEngineering，ChineseAcademyofSciences，Bering100190，China； 2．GraduateUniversityofChineseAcademyofSciences，Beijing100039，China； 3．InstituteofElectronics，ChineseAcademyofSciences，Beijing100190，China) Abs tract：Forincreasing the Signal—to—Noise RatioofNuclear Magnetic Resonanceexperiment，detection forsamples with nano—liter quantityandintegrationwithmicrofluidic，thefabricationofplanarmicrocoilswithhighQ valueispresented．Basedontheresultsof calculationforthesimulation ofSNR，severalkindsofgeometriesofcircularorsquare microcoilswerefabricated on glasssubstrates usingphotolith。g phy with SU一8andDC copperelectroplating．W iththehome—developedelectroplatingtechnology，thegrowingspeed ofcopperlayeris 1．2 ktm／min approximately．The geometriesforthe microcoilsfabricated suceessfugy are innerradius200 um ～ 1000 m，width & separation20gm 一80gm ，numberofturns1—9，wirethickness12 m ．UsingAgilent4294 ImpedanceAnalyzer， themeasuredRFparametersforNo．1000一lMicroeoilunder85MHz／2TeslaisRAC=7．25Q，L=285nH．Q：21．ThetrendofQ— frequencycurvemeasurediscompliancewiththatoftheresultsofsimulation，i．e．theQvaluereachesmaximumat85MHz．Compared with the measurementsin other public literatures，the performances given in this paper are competitive． Unlike the double—layer electroplatingscheme，this processof fabrication issimple and only one step of electroplating isneeded． Asa resultthe parasitic capacitanceofshortedleadersofmicrocoilisdecreasedremarkablewhileincreasingQvalue．Moreimportant，comp．aredwithsolenoid，in micronlevelthefabrication ofplanarmicrocoilismorecompatiblewith MEMS． Thisworkisan importantsteDtowardstheintegration ofNMRdetectionintomicro—totalanalysissystems(tzTAS)． Keywords：NMR planarmicrocoil；signal-to··noiseradio； MEM S；copperelectroplating