《PCBSurfaceFinishingReliability》由会员分享，可在线阅读，更多相关《PCBSurfaceFinishingReliability（16页珍藏版）》请在金锄头文库上搜索。
1、1PCB Surface FinishesPurpose: Prevent oxidation and deterioration of the copper, then to ensure excellent solderability of copper.Different types of finishes:Hot Air Solder Leveling (HASL) ): 喷锡/热风整平Immersion Tin: 化锡Electroless Nickel/Immersion Gold (ENIG) ): 化镍浸金ENEPIG: 化镍钯浸金Organic Solderability P
2、reservatives (OSP), Entek: 有机可焊性保护层Immersion Silver: 化银Mixed (ENIG + O.S.P)2Hot Air Solder Leveling (HASL)3HASL ProcessTin thickness: 50-100mil (for reference)Vertical and Horizontal solder spray - Thermal stress. - SnCu IMC (Intermatallic Compound) thickness. (V: 12-18 um, H:6-8um ). - Solderabilit
3、y, solder sag. - Cost.More Rework cant be more than 3times. Good shelf life. (12M, 7days after unpacking)Trane controls use HASL_V. - ACCE, EEV, XXL RP/ZE 4Immersion Tin5Electroless Nickel/Immersion Gold (ENIG)Trane controls use ENIG - TCS WTU/WCI, PZS.6ENIG ProcessProcess must be closely controlled
4、 to avoid quality problems: - Porous Gold - Black Pad - Scratch7Electroless Nickel/ Palladium Immersion Gold (ENEPIG)8Organic Solderability Preservatives (OSP)9Immersion Silver10PCB qualification and performance Spec.ItemTestRequirment1Bow and Twist=0.75% SMT, =1.5 others2SM/Legend/ENIG/Planting adh
5、esion3M 600 tape: No peeling, no particle 3Pencil test6H pencil is used which should not cut in or gouge thr solder mask.4Ionizable surface contaminants test1. ROSS: 1.56ug NaCl/sq.cm2. IC: Cl-: 2.0ug/sq.inch, Br-: 10.0ug/sq.inch5Solderability 1. Soldering float test2. Wetting balance6Heat Resistanc
6、e1. 288 solder float, 10s2. 8585%255ReflowNo delamination;7Flammability1. Laminates/PP/Solder mask2. 94HB, 94V-0, 94V-1, 94V-2, 94V-3, 5V.11PCB CleanlinessResistivity of Solvent Extract (ROSE)75% V/V 2-propanol/ DI waterIonic contaminants tester: OMEGA SMD 600Conductivity / g NaCl/L12PCB Cleanliness
7、 TestsIon Chromatography - 戴安公司（Dow Ion ExchangeExchange） ICS-1500Pretreatment: Sample is sealed in a clean bag along with a solution of 75% V/V 2-propanol/ DI water. Bag is placed in a water bath at 80C for 1 hour.Extract solution is then analyzed using ion chromatography.From XXL RP PCB DRW:Surface Insulation Resistance (SIR)13Wetting balance14Flammability test图图 1: 对于对于V0, V1, V2级别的级别的UL94燃烧性测试燃烧性测试No.SPECV-0V-1V-21燃烧时间（第一次、二次）10秒内30秒内30秒内2燃烧时间：二次+光闪时间30秒内60秒内60秒内3燃烧时间（5个之中第1、2之和）50秒内250秒内250秒内4坠落物引燃脱脂棉无无有5燃烧或光闪持续至样片根部不可不可不可15Heat-Resistance Factors16部分资料从网络收集整理而来，供大家参考，感谢您的关注！
