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1、Design. Build. Ship. Service.,锡膏印刷培训,Document Title : Lean Hand Book Document No : GBE-KPO-2-033-00 Doc. Revision : 02 Document Date : March 26, 2008,Business Excellence,2020/7/30,2,Technology,Screen printer/丝网印刷机,Solder Paste Printing 丝网印刷,2020/7/30,3,Technology,Describing the Stencil Printing Proc
2、ess丝网印刷工艺概述,2020/7/30,4,Technology,Zero Print Gap零印刷间隙,Metal sheet/金属平板,Open aperture/开孔,Basic Stencil Printing Process/基本丝网印刷工艺,2020/7/30,5,Technology,Controlled Print Speed 控制印刷速度 Even Squeegee Pressure 以及刮刀压力,Basic Stencil Printing Process, cont. /基本丝网印刷工艺（续）,Paste Rolling 锡膏滚动,2020/7/30,6,Techno
3、logy,Board is lowered under controlled Separation Speed 在“分离速度”控制下，板被分离下来,Basic Stencil Printing Process, cont. /基本丝网印刷工艺（续）,30-Jul-20,7,Technology,STENCIL钢网,30-Jul-20,8,Technology,Effect of stencil丝网的影响效果,With a good stencil优良的丝网 Excellent results极好的结果 Few failures很少的故障 Predictable yields可预知的合格率 Wi
4、th a bad stencil不良的丝网 Lots of stencil wiping需要大量的擦拭 Lots of bridges and insufficient disposition产生许多的桥连和少锡 Stencil Design Guideline: IPC 7525 丝网设计指导文件：IPC7525,30-Jul-20,9,Technology,Stencils Considerations 丝网的关键因素,Stencil Thickness丝网的厚度 Stencil Material丝网的材质 Stepped or uniformed thickness stencil 阶梯
5、式的或者同一厚度的丝网 Stencil Material Coefficient of Friction 丝网材质的摩擦系数 Stencil Surface Roughness 丝网的表面粗糙度 Stencil Hardness/Tensile Strength 丝网的硬度、抗拉强度 Framing Tension边框的张力 Mounting Material原料的装配 Partial or Full部分的和全部的,Aperture Size孔径尺寸 Aperture Shape & Wall 开口外形和内侧的形状 Aperture Arrangement开口排列 Aperture Aspec
6、t Ratio开口的纵横比例 Area Ratio面积比 Aperture Tolerance开口大小的公差 Aperture Gasketing开口的涂层 Aperture Location Tolerance 开口的位置公差 Thickness Tolerance厚度公差,30-Jul-20,10,Technology,Stencil Type丝网的类型,Full Stencil全平面丝网 Partial Stencil (stencil with mesh border) 局部的丝网 Polyester mesh (tension 22-30 Newtons per square cm)
7、 聚酯型网孔（表面张力在22-30N/cm2之间) Stainless steel mesh (tension 30-40 Newton per square cm) 不锈钢网孔（表面张力在30-40N/cm2之间） Frameless stencil 无框的丝网 MicroMount from DEKDEK公司的微小贴装丝网 TECFOIL from TECFOILTECFOIL公司的TECFOIL技术 SMart frame from SMTSMT小巧的外框,30-Jul-20,11,Technology,Stencil Fabrication Methods 丝网的制作方法,Chemic
8、al etch化学腐蚀 Single side etch单个侧面腐蚀 Dual side etch双行侧面腐蚀 Etch and electro-polish蚀刻和电抛光 Laser cut激光切割 Straight laser 直接光刻 Laser and polish 光刻并抛光 Electroform 电铸成型,Stencils are manufactured by three main methods: 制造丝网的主要三种方法,30-Jul-20,12,Technology,Wall characteristicChemical Etch 化学腐蚀孔内壁的特性,30-Jul-20,1
9、3,Technology,Cleaning of stencil,Whenever printing is completed, Clean the stencil with low lint paper soaked in IPA. 任何时候,只要印刷结束，就要用浸 有IPA的无尘纸擦净丝网 Use brush to clear paste in stencil aperture if necessary. 如果需要，用刷子清理丝网开孔,30-Jul-20,14,Technology,Stencil Handling丝网的使用,Handle the stencil with extreme
10、care. Any dents, crack or damages will result in poor print quality. 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 Always hold the stencil by the aluminum frame and do not drop any object on the stencil or foil.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 Do not set stencil down on surface that will damage the foil surface.不要
11、把丝网底部平放其它物体上，那样会损坏金属的表面,2020/7/30,15,Technology,The Perfect Print/完美的印刷,Clean edges/清洁的边缘 Flat on top/顶部平坦 Height = Stencil Thickness 高度=钢网厚度 Good Alignment/很好地对位 No Flux Bleed .无助焊剂溢出,2020/7/30,16,Technology,Paste Print Defect: Bridging/锡膏印刷缺陷：桥联,2020/7/30,17,Technology,Paste Print Defect: Excess P
12、rint Height/锡膏印刷缺陷：高度偏高,2020/7/30,18,Technology,Paste Print Defect: Scooping/锡膏印刷缺陷：塌陷,2020/7/30,19,Technology,Incomplete Print/不完全印刷（少锡）,2020/7/30,20,Technology,Paste Print Defect: Misalignment/锡膏印刷缺陷：偏位,2020/7/30,21,Technology,Tailing/锡膏拉尖,Acceptable/可接受 (Solder smear or slump 10%) 锡量减少10%,Reject/
13、拒收 (Solder smear or slump 10%) 锡量减少10%,Solder Paste Print Quality/锡膏印刷质量,2020/7/30,22,Technology,Paste Clogging锡膏堵塞,Acceptable/可接受 (paste deposit 90%) 焊盘锡量超过90%,Reject/拒收 (paste deposit 90%) 焊盘锡量超过90%,Solder Paste Print Quality /锡膏印刷质量,2020/7/30,23,Technology,Smearing and Slumping/锡膏塌陷,Acceptable/可接
14、受 (Solder smear or slump 10%) 塌陷小于10%,Reject/拒收 (Solder smear or slump 10%) 塌陷大于10%,Solder Paste Print Quality,2020/7/30,24,Technology,Major contributor to defects/缺陷的主要分布,Source: MPMs A users guide to more Precise SMT printing,2020/7/30,25,Technology,Hardware/硬件,Software/软件,Environment/环境,Squeegees
15、/刮刀,Print Speed/印刷速度,Temperature/温度,Paste/锡膏,Humidity/湿度,Stencil/钢网,Pressure/压力,Tooling/surport pin,Print Gap/印刷间隙,Board/印刷线路板,Separation Speed/分离速度,Factors Affecting the Print/影响印刷的因素,2020/7/30,26,Technology,Squeegee/刮刀,2020/7/30,27,Technology,Squeegee Type/刮刀类型,Diamond edgeTrailing edgeD cut,2020/
16、7/30,28,Technology,Squeegee Material/刮刀材料,Polyurethane/聚亚安酯 Composite/合成物 2 part polyurethane Epoxy/环氧树脂 Metal/金属 Plain Steel/平钢 Polished/被抛光 Rolled Lubricated surface Teflon Permalex,2020/7/30,29,Technology,Squeegee/刮刀,Hardness/硬度 : 30 to 90 durometer (Shore A) with 60 to 90 durometer most used, metal. Attack Angle/接触角度 : 45 to 75 degrees Pressure/压力 Parallelism/平行度,2020/7/30,30,Technolog
