1Prepared by: Bin LiuPrepared by: Bin LiuDate:9/25/2005Date:9/25/2005镭射钻孔培训教材2前言前言LASERLASER钻孔简介钻孔简介LASERLASER钻机介绍钻机介绍MicroviaMicrovia制作工艺制作工艺Microvia Microvia 常见缺陷分析常见缺陷分析目录目录3 随着PCB向微型和高密度互连的方向发展，越来越多制板采用微导孔的连接方式实现高密度互连，而目前制作微导孔的主要方法是laser drill。如何利用现有镭射钻机制作出各种高质量的microvia，是现在PCB制造的迫切任务。 前言前言前言前言41、LASER分类100 nm 5th H, 4th H, 3rd H, Ar-Ion 2nd H, Nd:YAG Nd:YAG Nd:YAG Nd:YAG Nd:YAG Nd:YLFWavelength212 nm266 nm355 nm488 nm532 nm1064 nmVISIBLEINFRAREDULTRAVIOLET1000 nm10,000 nm400 nm750 nm1321 nm光谱图Laser Laser Laser Laser 钻孔简介钻孔简介钻孔简介钻孔简介 激光类型主要包括红外光红外光和紫外光紫外光两种；52、常见的LASER激发方式Laser Laser Laser Laser 钻孔简介钻孔简介钻孔简介钻孔简介1)LASER 类型UV激发介质YAG激发能量发光二极管代表机型：ESI 53202)LASER 类型 IR（RF-Radio Frequency）激发介质密封CO2气体激发能量高频电压代表机型：HITACHI LC-1C21E/1C3)LASER 类型 IR（TEA-Transverse excited atmospheric横波激励）激发介质外供CO2气体激发能量高压电极代表机型：SUMITOMO LAVIA 1000TW63.1、CO2的成孔原理利用红外线的热能，当温度升高或能量增加到一定程度后，如有机物的熔点、燃点或沸点时，则有机物分子的相互作用力或束缚力将大为减小到使有机物分子相互脱离成自由态或游离态，由于激光的不断提供能量，而使有机分子逸出或者与空气中的氧气燃烧而成为二氧化碳或水气体而散离去，由于激光是以一定直径的红外光束来加工的，因而形成微小孔。Absorptionand HeatingThermalConductionLightMeltingLiquidInterfaceVaporizationPlasma ProductionLaser Laser Laser Laser 钻孔简介钻孔简介钻孔简介钻孔简介7固态Nd：YAG紫外激光器发射的是高能量的紫外光光束，利用其光学能(高能量光子)，破坏了有机物的分子键(如共价键)，金属晶体(如金属键)等，形成悬浮颗粒或原子团、分子团或原子、分子而逸散离出，最后形成盲孔。吸收吸收破坏分子破坏分子(原子原子)键键成孔成孔长链大分子长链大分子小粒子逃逸小粒子逃逸Laser Laser Laser Laser 钻孔简介钻孔简介钻孔简介钻孔简介3.2、UV的成孔原理84、常见LASER的加工材料 Epoxy FR4 ARAMID COPPER BTv现已加工的介质材料包括：RCC、1X1080、2X1080、2116、2X106、ARAMIDLaser Laser Laser Laser 钻孔简介钻孔简介钻孔简介钻孔简介9吸收率吸收率波长波长 (um)ResinMatte CuGlassUVIRVISIBLE00.10.20.30.40.50.60.70.80.910.2 0.30.4 0.5 0.60.7 0.8 0.911.1 1.2各种材料都吸收树脂吸收红外光强玻璃反射铜反射由于不同材料对各类激光的吸收均不相同，导致LASER加工混合材料时的困难。Laser Laser Laser Laser 钻孔简介钻孔简介钻孔简介钻孔简介4.1、不同材料对波长的吸收情况（2000版本）10Laser Laser Laser Laser 钻孔简介钻孔简介钻孔简介钻孔简介4.2、不同材料对波长的吸收情况（2001版本）11Aspect Ratio500 450 400 350 300 250 200 150 100 50 mmThru ViasBlind Vias10:11:1.1:1UV YAGCO2Photo-viaMechanicalDrill5、各种方法加工孔直径的范围Laser Laser Laser Laser 钻孔简介钻孔简介钻孔简介钻孔简介12我司现有 Laser 钻机HITACHI LC-1C21E/1CLC-2F21SE/1CLC-2F212SE/2CLC-2G212E/2CLC-2G212BE/2CSUMITOMOLAVIA 1000TWESI53205330Laser Laser Laser Laser 钻机介绍钻机介绍钻机介绍钻机介绍 ESI 5320v高频率低功率脉冲v 固态激光激发装置，无须外部供气v “冷光”，产生热量少Hitachiv RF Excited 密封气体激发v 无须定期换气v 每四小时需做精度校正SUMITOMO v 外部供气v 须定期换气v 加工时有能量检测和补打功能13ESI UV Laser对位系统对位系统1内层靶标对位内层靶标对位Laser Laser Laser Laser 钻机介绍钻机介绍钻机介绍钻机介绍UV Laser刮内层靶标图形刮内层靶标图形定位补偿方法4 points allow correction of x - y offset, rotation, scale, and keystone1415.7 mil Through Hole3 mil Hole8 mil Pad40 mil PadLaser Laser Laser Laser 钻机介绍钻机介绍钻机介绍钻机介绍ESI UV Laser对位系统对位系统2通孔对位通孔对位151.对位标靶-圆形2.对位补偿类似ESILaser Laser Laser Laser 钻机介绍钻机介绍钻机介绍钻机介绍HITACHI &SUMITOMO Laser对位系统对位系统Conformal Mask靶标对位靶标对位16Laser BeamGalvoUV LaserCO2 Laser光学系统光学系统Laser Laser Laser Laser 钻机介绍钻机介绍钻机介绍钻机介绍17Copper surface is cleaned and texturedESI UV Laser的钻孔参数的钻孔参数:Laser Laser Laser Laser 钻机介绍钻机介绍钻机介绍钻机介绍调整调整调整调整LaserLaser焦距焦距焦距焦距Step One: Drill CopperStep Two: Remove Dielectric25mm50 - 100mmFocused spotSmall spot sizeHigh energy densityDe-focused spotLarger spot sizeLower energy densityStop on inner copper layer18Laser Laser Laser Laser 钻机介绍钻机介绍钻机介绍钻机介绍DielectricCopperPlanesPunchingDielectricCopperPlanesTrepanningSpiralingDielectricCopperPlanesESI UV Laser的钻孔参数的钻孔参数:19 Cycle Mode Burst ModeStep ModeLaser Laser Laser Laser 钻机介绍钻机介绍钻机介绍钻机介绍Hitachi &Sumitomo Laser的钻孔参数的钻孔参数:即对在一个区域内所有的孔进行第一个脉冲加工，完毕后，再进行第二个脉冲加工，如此类推。即对一个孔进行所有的脉冲加工后，才对下个孔进行加工。20钻孔速度钻孔速度HITACHImax 1200脉冲/秒SUMITOMOmax 1000脉冲/秒ESI 15K30K70K脉冲/秒Laser Laser Laser Laser 钻机介绍钻机介绍钻机介绍钻机介绍21一阶盲孔：A、CO2 laser drillB、CO2 laser direct drillC、UV direct drillD、UV+CO2 laser drillMicroviaMicroviaMicroviaMicrovia制作工艺制作工艺制作工艺制作工艺22MicroviaMicroviaMicroviaMicrovia制作工艺制作工艺制作工艺制作工艺二阶盲孔(钻Stacked via)：A、UV Direct drillB、UV + CO2C、Conformal mask + CO2 +UVD、UV + Conformal mask + CO223五、Microvia 缺陷分析 -缺陷类型缺陷类型 -产生原因和影响产生原因和影响 -解决方法解决方法Laser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析24(1)Under Cut(2)Delaminate(4)Remained Glass Fiber(5)Remained Resin(8)Void (7)Damage(6)Micro Crack Barrel Shaped Inner HoleLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析Laser 盲孔缺陷盲孔缺陷25 PROBLEMS Under Cut Delaminate Cause and Effect Heat accumulation from RCC copper surface Impact to the RCC surface by Laser Beam (1)Under Cut(2)DelaminateLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析26 Solution Short pulse width Reduce the pulse energyLASER BeamLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析27 PROBLEMS Barrel Shaped Inner Hole Cause and Effect Reflection from hole bottom Incorrect position of Laser mode(single mode)to the hole Barrel Shaped Inner HoleLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析28Reflection LASER Beam abSingle ModeLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析29 Solution Short pulse(less than less) The best suited number of shots Multi-mode BeamSingle-modeMulti-mode(top-flat)Laser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析30 PROBLEMS Remained Glass Fiber Cause and Effect Difference Nature against heat between resin and glass Solution High peak power processing Cycle-mode processing(4)Remained Glass FiberLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析31 PROBLEMS Remained Resin Cause and Effect a.Very thin smeared resin on the bottom of hole not reach sublimation point(5)Remained ResinLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析32b. Unsuitability of resin thickness c. Single-mode processing60m80mLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析33d. Unsuitability of LASER pulse energy e. Incorrect position of LASER BeamAccuracy of XY tableAccuracy of ScannersAlignment Accuracy against PWB elasticityPWB warp Laser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析34 PROBLEMS Micro Crack Cause and Effect The pressure from resin sublimation by LASER(6)Micro CrackLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析35Solution -Short Pulse(less than less) -The best suited shape of LASER wave -The best pulse energy adapt to nature of material( Standard:about 10J/cm2,pulse width less than 1 us)Laser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析36 PROBLEMS Damage Void Cause and Effect a.If the pulse width(irradiation time) is long, the temperature of substrate surface is risen up. (8)Void (7)DamageLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析37b. Center portion of Copper foil have damage due to Single Beam Solution Short Pulse Multi-Mode BeamCenter damageLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析38The quality of McroviaCO2Laser drill RCC CO2Laser drill aramidLaser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析39CO2Laser drill FR4Laser Laser Laser Laser MicroviaMicroviaMicroviaMicrovia缺陷分析缺陷分析缺陷分析缺陷分析40