SMT锡膏印刷培训

Design.Build.Ship.Service.锡膏印刷培训DocumentTitle:LeanHandBookDocumentNo:GBE-KPO-2-033-00Doc.Revision :02DocumentDate:March26,2008BusinessExcellence2023/11/192TechnologyScreenprinter/丝网印刷机SolderPastePrinting丝网印刷丝印机Chip贴片机多功能贴片机多功能贴片机Chip贴片机回流炉2023/11/193TechnologyDescribingtheStencilPrintingProcess

丝网印刷工艺概述2023/11/194Technology15mmminDia.Paste/最小直径15mm的锡膏体Zero‘PrintGap’零印刷间隙Metalsheet/金属平板Openaperture/开孔BasicStencilPrintingProcess/基本丝网印刷工艺2023/11/195TechnologyControlled‘PrintSpeed’控制印刷速度Even‘SqueegeePressure’以及刮刀压力BasicStencilPrintingProcess,cont./基本丝网印刷工艺（续）PasteRolling锡膏滚动2023/11/196TechnologyBoardisloweredundercontrolled‘SeparationSpeed’在“分离速度”控制下，板被分离下来BasicStencilPrintingProcess,cont./基本丝网印刷工艺（续）19-Nov-237TechnologySTENCIL钢网19-Nov-238TechnologyEffectofstencil丝网的影响效果Withagoodstencil优良的丝网Excellentresults极好的结果Fewfailures很少的故障Predictableyields可预知的合格率Withabadstencil不良的丝网Lotsofstencilwiping需要大量的擦拭Lotsofbridgesandinsufficientdisposition产生许多的桥连和少锡StencilDesignGuideline:IPC7525丝网设计指导文件：IPC752519-Nov-239TechnologyStencilsConsiderations丝网的关键因素StencilThickness丝网的厚度StencilMaterial丝网的材质Steppedoruniformedthicknessstencil阶梯式的或者同一厚度的丝网StencilMaterialCoefficientofFriction丝网材质的摩擦系数StencilSurfaceRoughness丝网的表面粗糙度StencilHardness/TensileStrength丝网的硬度、抗拉强度FramingTension边框的张力MountingMaterial原料的装配PartialorFull部分的和全部的ApertureSize孔径尺寸ApertureShape&Wall开口外形和内侧的形状ApertureArrangement开口排列ApertureAspectRatio开口的纵横比例AreaRatio面积比ApertureTolerance开口大小的公差ApertureGasketing开口的涂层ApertureLocationTolerance开口的位置公差ThicknessTolerance厚度公差19-Nov-2310TechnologyStencilType丝网的类型FullStencil全平面丝网PartialStencil(stencilwithmeshborder)

局部的丝网Polyestermesh(tension22-30Newtonspersquarecm)聚酯型网孔（表面张力在22-30N/cm2之间)Stainlesssteelmesh(tension30-40Newtonpersquarecm)

不锈钢网孔（表面张力在30-40N/cm2之间）Framelessstencil无框的丝网MicroMountfromDEKDEK公司的微小贴装丝网TECFOILfromTECFOILTECFOIL公司的TECFOIL技术SMartframefromSMTSMT小巧的外框19-Nov-2311TechnologyStencilFabricationMethods丝网的制作方法Chemicaletch化学腐蚀Singlesideetch单个侧面腐蚀Dualsideetch双行侧面腐蚀Etchandelectro-polish蚀刻和电抛光Lasercut激光切割Straightlaser直接光刻Laserandpolish光刻并抛光Electroform电铸成型

Stencilsaremanufacturedbythreemainmethods:制造丝网的主要三种方法19-Nov-2312TechnologyWallcharacteristic

ChemicalEtch化学腐蚀孔内壁的特性19-Nov-2313TechnologyCleaningofstencilWheneverprintingiscompleted,CleanthestencilwithlowlintpapersoakedinIPA.任何时候,只要印刷结束，就要用浸有IPA的无尘纸擦净丝网．Usebrushtoclearpasteinstencilapertureifnecessary.如果需要，用刷子清理丝网开孔．19-Nov-2314TechnologyStencilHandling丝网的使用Handlethestencilwithextremecare.Anydents,crackordamageswillresultinpoorprintquality.移动丝网时，要万分小心．任何破边，破碎，或损坏都将导致糟糕的印刷质量．Alwaysholdthestencilbythealuminumframeanddonotdropanyobjectonthestencilorfoil.保持丝网在铝框中永远处于绷紧状态，并且严禁把东西放在丝网上．Donotsetstencildownonsurfacethatwilldamagethefoilsurface.不要把丝网底部平放其它物体上，那样会损坏金属的表面．2023/11/1915TechnologyThePerfectPrint/完美的印刷Cleanedges/清洁的边缘Flatontop/顶部平坦Height=StencilThickness高度=钢网厚度GoodAlignment/很好地对位NoFluxBleed...无助焊剂溢出2023/11/1916TechnologyPastePrintDefect:Bridging/锡膏印刷缺陷：桥联2023/11/1917TechnologyPastePrintDefect:ExcessPrintHeight/锡膏印刷缺陷：高度偏高2023/11/1918TechnologyPastePrintDefect:Scooping/锡膏印刷缺陷：塌陷2023/11/1919TechnologyIncompletePrint/不完全印刷（少锡）2023/11/1920TechnologyPastePrintDefect:Misalignment/锡膏印刷缺陷：偏位2023/11/1921TechnologyTailing/锡膏拉尖Acceptable/可接受(Soldersmearorslump<10%)锡量减少<10%Reject/拒收(Soldersmearorslump>10%)锡量减少>10%SolderPastePrintQuality/锡膏印刷质量2023/11/1922TechnologyPasteClogging锡膏堵塞Acceptable/可接受(pastedeposit>90%)焊盘锡量超过90%Reject/拒收(pastedeposit<90%)焊盘锡量超过90%SolderPastePrintQuality/锡膏印刷质量2023/11/1923TechnologySmearingandSlumping/锡膏塌陷Acceptable/可接受(Soldersmearorslump<10%)塌陷小于10%Reject/拒收(Soldersmearorslump>10%)塌陷大于10%SolderPastePrintQuality2023/11/1924TechnologyMajorcontributortodefects/缺陷的主要分布Source:MPM’sAuser’sguidetomorePreciseSMTprinting2023/11/1925TechnologyHardware/硬件Software/软件Environment/环境Squeegees/刮刀PrintSpeed/印刷速度Temperature/温度Paste/锡膏Humidity/湿度Stencil/钢网Pressure/压力Tooling/surportpinPrintGap/印刷间隙Board/印刷线路板SeparationSpeed/分离速度FactorsAffectingthePrint/影响印刷的因素2023/11/1926TechnologySqueegee/刮刀2023/11/1927TechnologySqueegeeType/刮刀类型Diamondedge Trailingedge ‘D’cut2023/11/1928TechnologySqueegeeMaterial/刮刀材料Polyurethane/聚亚安酯Composite/合成物2partpolyurethaneEpoxy/环氧树脂Metal/金属PlainSteel/平钢Polished/被抛光RolledLubricatedsurfaceTeflonPermalex2023/11/1929TechnologySqueegee/刮刀Hardness/硬度:30to90durometer(ShoreA)with60to90durometermostused,metal.AttackAngle/接触角度:45to75degreesPressure/压力Parallelism/平行度2023/11/1930TechnologyScanpicofrubberandmetalsqueegee,paste,cyberoptics橡胶和金属刮刀，锡膏，影像Scavenging2023/11/1931TechnologyPrintParameters/印刷参数PrintSpeed/印刷速度SqueegeePressure/刮刀压力SeparationSpeed/分离速度PrintGap/印刷间隙UnderScreenCleanRate/钢网底板清洗频率PasteDispense/加锡膏Environment/环境2023/11/1932TechnologyT