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1、Wettability testing of copper based surface finishes for lead free assembly/各表面處理的無(wú)鉛焊接 焊錫性痂試Information provide by Atotech/ 資料由Atotech提供 2006.3.2Training principle/培訓(xùn)原貝UNo advertisement/拒絕做廣告Focus on experimental methodology and conclusions/注重于實(shí)驗(yàn)方法和結(jié)論With the aim of learning and self- improvement/本著
2、學(xué)習(xí)和自我提升的思想On the basis of discussion and communication/立足于交流與討論P(yáng)T manager claims/生技經(jīng)理宣A few notes /幾點(diǎn)說(shuō)明This is a genuine piracy/本報(bào)告純屬盜版Feel free to ask/有問(wèn)題盡管問(wèn)Prepare for my questions/請(qǐng)準(zhǔn)備解答我的問(wèn) 題Correct any existing mistake/ 糾正所有存在的 錯(cuò)誤The accuracy of the data is reserved/ 本人不 負(fù)責(zé)數(shù)據(jù)的準(zhǔn)確性力Jeek claims/袁進(jìn)宣C
3、ontent/ 內(nèi)容General introduction/簡(jiǎn)介Reflow profiles/回流焊溫度曲線(xiàn)Wettability testing &methods/潤(rùn)濕性測(cè)試與方法Discussion/討論Conclusion/結(jié)論Whafs different in lead free soldering?/ 無(wú)到底木同在哪里卩Peak temperature is higher/最高焊接溫度 更高了Time above liquidus is longer/ 焊料在熔化 狀態(tài)下的時(shí)間更長(zhǎng)了Solder composition is different/焊料的成份有變化What doe
4、s it mean?/ 無(wú)鉛焊接意味著什么?Higher temperature/longer times/different solder alloy/更高的焊接溫度/更長(zhǎng)的熔錫時(shí)間/焊料合金 成份的變化Stronger oxidation of solder paste and surface finish/ 焊膏和表面處理的氧化更嚴(yán)重anThickness of IMC increased/合金層厚度更厚Metallurgy of solder joints is different/焊接點(diǎn)金屬特性 的變化No long term production experience/沒(méi)有長(zhǎng)期的
5、量產(chǎn)經(jīng)驗(yàn)Reflow equipment/回流焊設(shè)備Reflow equipment for investigations/ 用于研究爾面流焊設(shè)備REHM Nitro 2100N2 atmosphere with controlled O2 concentration/M 氣保護(hù),控制 氧氣含量5 heating zones/ 5 個(gè)加熱段 Convection reflow system/對(duì)流 傳熱回流焊系統(tǒng)Used reflow profile for subsequent aging and soldering/后續(xù)的老化實(shí)驗(yàn)和 焊接的溫度曲線(xiàn)Eutectic tin lead/錫鉛合金
6、Lead free/無(wú)鉛焊料SnAgCu/錫銀銅比307Peak最高溫度210/46s秒183CPeak最高溫度260/60s秒217CSn/Pb/錫鉛比 63/37/All profiles same duration of time各種溫度曲線(xiàn)所經(jīng)歷的時(shí)間Copper based final finishes, investigated layers研究的各種表面處理層Surface finish/表面處理Specification/規(guī)格Immersion tin/化學(xué)錫1.2um, incl. anti-whisker additive/1.2um厚, 含防錫鬚添加劑Immersion
7、silver/化學(xué)銀0.2um, commercially available silver/organic / 0.2um厚,市面上的含有機(jī)保 護(hù)膜的產(chǎn)品HASL/熱風(fēng)整平(噴錫)SnCuNi, horizontally processed/水平線(xiàn)OSP/有機(jī)保護(hù)膜Lead free compatible/無(wú)鉛焊接型Wettability testing/潤(rùn)濕性測(cè)試Comparison of/對(duì)比性測(cè)試項(xiàng)目Wetting balance/潤(rùn)濕平衡性測(cè)試Solder spread/錫料延伸性測(cè)試Mis-print test/絲印錯(cuò)位測(cè)試De-wetting/縮錫測(cè)試Varying/可變因素So
8、lder flux/不同的助焊劑Solder alloys/eutectic tin-lead vs. lead-free/ 不同的焊料一錫鉛焊 料與無(wú)鉛焊料Soldering atmosphere/ air vs. N?/在空氣中焊接與在氮?dú)獗Wo(hù)下 焊接Wetting balance潤(rùn)濕平衡測(cè)試/MetronelecST60(設(shè)備名稱(chēng))Operator independent test method/采用無(wú)人員差異性的方法Especially design coup on/特 別設(shè)計(jì)的coupon10 coupons per surface/test 每面或測(cè)測(cè)喩10個(gè)couponThe t
9、ested samples are fluxed before immersed into the solder pot/測(cè)試樣 本在浸錫前需上助焊劑Results are given for wetting force and wetting time/設(shè)備用于j閏濕力了則試 和潤(rùn)濕時(shí)間測(cè)試Sequence/mechanism similar to wave soldering/模擬波峰焊的步驟和機(jī)理Tested fluxes/測(cè)試用 的助焊劑種類(lèi)Activity level of flux/Flux residue 助焊劑 種類(lèi)Presence of halide/ 是否含鹵素IPC-fl
10、ux acc.to J-STD- 003ALow低Yes是Stannol 500-6 BModerate 中等No否Litton Kester 950E3Low低No否Using solder pot with SnAg3.5Cu0.7 alloy/錫爐采用SnAg3.5Cu0.7的合金260CAir atmosphere/空氣中測(cè)試Wetting balance test - Wetting force/潤(rùn)濕平衡測(cè) 試一潤(rùn)濕力測(cè)試Initial test to determine solder flux for subsequent testing/本實(shí)驗(yàn)為初步 實(shí)驗(yàn),主要用于為后續(xù)試驗(yàn)選取
11、助焊劑SnAg3.5Cu0.7 alloy at 260C/ air atmosphere條件:空氣作業(yè),錫銀銅合金,260C0,25 n-505- 1 1 o EEio】謔踏0,00OSPImmersion tin化學(xué)錫Immersion silverI organic化學(xué)銀+宥機(jī)膜HASL噴錫No wetting force using the litton kester flux/ 使用 litton kester沒(méi)用潤(rùn)濕力口 I PC - Flux Stannol Kolo 500-6-B Litton Kester 950 E3Tested fluxes had minor impa
12、ct to wetting force 結(jié)論:各種助焊劑對(duì)潤(rùn)濕力影響不大Wetting balance test - Wetting time/潤(rùn)濕平衡測(cè) 試一潤(rùn)濕時(shí)間測(cè)試Initial test to determine solder flux for subsequent testing/本實(shí)驗(yàn)為初步 實(shí)驗(yàn),主要用于為后續(xù)試驗(yàn)選取助焊劑SnAg3.5Cu0.7 alloy at 260C/ air atmosphereChoice of soldering flux strongly impacts wetting time 結(jié)論:助焊劑的選擇對(duì)潤(rùn)濕時(shí)間的影響很大Wetting balan
13、ce test - Wetting time/潤(rùn)濕平 衡躺-潤(rùn)濕時(shí)間測(cè)試Vy After reflow ageing/ reflow老化實(shí)驗(yàn)后 As received After 1st reflow After 2nd reflow After 3rd reflowNitrogen atmosphere during aging/ soldering improves wetting time 結(jié)論:在老化實(shí)驗(yàn)和焊接時(shí)使用氮?dú)獗Wo(hù)能夠改善潤(rùn)濕時(shí)間Wetting balance test - Wetting time/潤(rùn)濕平 衡測(cè)試一潤(rùn)濕時(shí)間測(cè)試Immersion tin 一 Tin lead
14、 vs. lead free solder alloy化學(xué)錫表面處理-錫鉛焊接與無(wú)鉛焊接的對(duì)比口 Lead free / nitrogen atmosphere Tin lead / air atmosphere Lead free / air atmosphere5 0 5 0 5 02 2 九 九 a asj Quin.Litton Kester 950 E3 助焊劑As received After 1st reflow After 2nd reflow After 3rd reflowLead free using N2 atmosphere shows equivalent wett
15、ing time to eutectic 結(jié)論:使用氮?dú)獗Wo(hù)的無(wú)鉛焊接與錫鉛焊接的潤(rùn)濕時(shí)間相當(dāng)Wetting balance test/潤(rùn)濕平衡測(cè)試(小結(jié)篇)Impact of flux, alloy and atmosphere on Metronelec test/ 助焊劑,焊料成份和是否有氮?dú)獗Wo(hù)的影響(在Metronelec上測(cè)試)Tested “moderate” activated flux showed no improvement/中等活性的助焊劑沒(méi)有改善作用Tested “halogen” containing flux only improves for OSP/助焊劑是否
16、含鹵素只對(duì)OSP表面處理有影響Nitrogen atmosphere improved wetting time for all finishes/M氣保護(hù)對(duì)所有表面處理的潤(rùn)濕時(shí)間都有貢獻(xiàn)Immersion tin 一 showed comparable wetting time for lead free in combination with nitrogen atmosphere to eutectic tin lead/對(duì)于化學(xué)錫表面處理來(lái)說(shuō),在氮?dú)獗Wo(hù)下的無(wú)鉛焊接 與在空氣環(huán)境中的錫鉛焊接潤(rùn)濕時(shí)間相當(dāng)Wettability testing/ 潤(rùn)濕性測(cè)試Solder spread(錫料
17、延伸性測(cè)試)/ mis print(絲印錯(cuò)位實(shí)驗(yàn))/ de-wetting(縮錫實(shí)驗(yàn))Solder alloys - pastes(錫膏)Tin/lead(錫鉛)- Senju OZ AT-221CM-42-10(peak最高焊接溫度 210C)/ NC-SMQ 92H (peak最高焊接溫度 210C)C Lead-free(無(wú)鉛)- KOKI S3X5&M406 (Sn/Ag3.0/Cu0.5)(最高焊 接溫度 peak 260C)/ Indium5.8 LS (Sn/Ag3.0/Cu0.5)(最高焊接 溫度 peak 260C)Atmosphere (實(shí)驗(yàn)環(huán)境)Air/空氣中N2/氮?dú)獗?/p>
18、護(hù)Wettability testing/ 潤(rùn)濕性測(cè)試Solder spread(錫料延伸性測(cè)試)40 solder dots per surface/test 每衣面/測(cè)試40個(gè)焊點(diǎn)surface FnishPrntec Solder paste1coaperP30Reflowsd Sol de* PasteSolder paste printing on a solderable surface/將錫膏印在可焊表面 The spread of liquefied and solidified solder is measure/量湫Q熔化擴(kuò) 張凝固后的焊料尺寸Solder spreads
19、in all di recti ons (360) only on the pad surface (2 dimensional)/焊料在pad表面二維的向各術(shù)方向擴(kuò)嗾Sequence/mechanism similar to v standard SMT reflow soldering/ 程序機(jī)理模擬標(biāo)準(zhǔn)的SMT回流焊Wettability testing/ 潤(rùn)濕性測(cè)試Solder spread(錫料延伸性測(cè)試)Immersion tin/化學(xué)錫Immersion silver幷匕學(xué)金艮OSP/有機(jī)保護(hù)膜Only the bulk soldered diameter was measure
20、d, not the solder spikes/量測(cè)時(shí)只量測(cè)大塊的熔錫而不算單點(diǎn)的錫突點(diǎn)Wettability testing/ Solder spread 潤(rùn)濕性測(cè)試/錫 料延伸性測(cè)試Comparison of atmosphere during ageing and soldering/對(duì)比老化和焊接時(shí)空氣保護(hù) 的作用 As received After 1 st reflow After 2nd reflow After 3rd reflowHASL was the only finish that exhibited a decrease in area after ageing/只
21、有噴錫 表面處理在老化實(shí)驗(yàn)后出現(xiàn)縮錫現(xiàn)象Slight improvement using N2 atmosphere during ageing and reflow soldering/ 在老 化實(shí)驗(yàn)和焊錫時(shí)使用空氣保護(hù)只有微小的改善作用Wettability testing/ Solder spread 潤(rùn)濕性測(cè)試/ 錫料延伸性測(cè)試Immersion tin - Tin lead vs. lead free solder alloy/化學(xué)錫表面處理一錫鉛焊接與無(wú)鉛 焊接的對(duì)比 Senju OZ AT-221 CM5-42-10 f 210C / air110Completely melte
22、d黃】sealou- sure KOKI S3X58-M406 / 260C f air KOKI S3X58-M406 / 260C / nitrogen,r As received After 1st reflow After 2nd reflow After 3rd reflow-15 JNitrogen atmosphere during lead free reflow ageing could not achieve same wetted area as eutectic tin lead/競(jìng)管在老化和焊接時(shí)應(yīng)用氮?dú)獗Wo(hù) 無(wú)鉛焊接荏苒無(wú)法達(dá)到錫鉛焊接的潤(rùn)濕面積Wettabilit
23、y testing/ Solder spread 潤(rùn)濕性測(cè)試/ 錫瘋貳創(chuàng)、結(jié)篇)Impact of paste, alloy and atmosphere on solder spread test /錫膏合金成份和是否有氮?dú)獗Wo(hù)對(duì)錫料延展性測(cè)試的影響HASL was the only finish that showed a decrease in area after ageing/只有噴錫表面處理在老化實(shí)驗(yàn)后岀現(xiàn)縮錫現(xiàn)象Slight improvement using N2 atmosphere during ageing andreflow soldering/在老化實(shí)驗(yàn)和回流焊時(shí)使用
24、氮?dú)獗Wo(hù)只有微小的改善作用Immersion tin 一 nitrogen atmosphere during lead free reflow ageing could not achieve same wetted areas as eutectic tin lead/化學(xué)錫表面處理-在無(wú)鉛焊接老化試驗(yàn)時(shí)使用氮?dú)獗Wo(hù) 荏苒無(wú)法達(dá)到錫鉛焊接的潤(rùn)濕面積Wettability testing/Mis print test 潤(rùn)濕性測(cè)試/絲網(wǎng)錯(cuò)位測(cè)試(小結(jié)篇)40 OFP pads per surface/test 每面/ 測(cè)試40個(gè)QFP padw_=_=_=_=_一Printed Solder
25、PasteR eflowed S ol der PasteSolder paste printed on a solderable surface/ 將焊膏印在可焊接的表面 The spread of liquefied and solidified solder is measured/量測(cè)熔化擴(kuò)張 凝固后的焊料尺寸Solder spreads in only one direction surrounding 3 sides of the NSMDOFP surface (3dimensional)/焊料的擴(kuò)張只有一Y固方向,同時(shí)又是包圍 OFP的三個(gè)面的(此是三維的)Sequence/
26、mechanism similar to SMD reflow soldering, but paste printing simulates an accident in pasting printing/程序和機(jī)理模擬SMD回 流焊,但是焊料印刷故意印偏Wettability testing/Mis print test 潤(rùn)濕性測(cè)試/ 絲網(wǎng)錯(cuò)位測(cè)試JI 丿”Comparison of atmosphere during ageing and soldering/ 對(duì)比老化和焊接時(shí) 是否有氮?dú)獗Wo(hù)的影響N2 atmosphere improves coverage and minimize
27、discoloration 結(jié)論:氮?dú)獗Wo(hù)增加了焊料的覆蓋率,同時(shí)對(duì)變色也有貢獻(xiàn)Wettability testing/Mis print test 潤(rùn)濕性測(cè)試/絲網(wǎng)錯(cuò)位測(cè)試Immersion Tin - Tin lead vs. lead free solder alloy 化學(xué)錫表面處理-錫鉛焊料與無(wú) 鉛焊料的對(duì)比As received耒鰹老化1 x rf2x rT3x rf兩雄卿三蜩磐4h 155C24h 85/85Sn/Pb210QCSAC260 Cn2B 1 vw. * 7S JSZ=22 L-=t = f s t 芝 f=| 三|三4三I100 %73 %62 %65100%81
28、%re%86%G5%=100%100%SAC260 Cair一_52_51Wettability testing/Mis print test 潤(rùn)濕性測(cè)試/絲網(wǎng)錯(cuò)位測(cè)試N2 atmosphere shows equivalent coverage to eutectic 結(jié)論:在無(wú)鉛焊接時(shí),使用氮?dú)獗Wo(hù)可以達(dá)到錫鉛焊接類(lèi)似的覆蓋率51Wettability testing/Mis print test 潤(rùn)濕性測(cè)試/絲網(wǎng)錯(cuò)位測(cè)試(小結(jié)篇)Impact of paste, alloy and atmosphere on Mis print test /錫膏合金成份和是否 有氮?dú)獗Wo(hù)對(duì)絲印錯(cuò)位測(cè)試的
29、影響All surface showed an improvement using nitrogen atmosphere/氮?dú)獗Wo(hù)對(duì)住何一利嚷面嚨輕訛有童獻(xiàn)Test results are in contradiction to solder spread testing (same surface finish, paste and atmosphere)/ 絲印錯(cuò)位實(shí)驗(yàn) 劃結(jié)果與錫料延展性潮試的結(jié)果并不一致性(相同的表面處理, 焊料以及實(shí)驗(yàn)環(huán)境)The HASL surface was the only finish that showed a strong yellow during
30、ageing in air atmosphere/只有噴錫表面處理在 空氣中進(jìn)行蚤化實(shí)礙時(shí)表面會(huì)有裁黃現(xiàn)象Immersion tin 一 equivalent test results are achieved compared to eutectic tin lead testing/化學(xué)錫的表面處理在氮 氣保護(hù)下的無(wú)鉛焊接可以達(dá)到在空氣中錫鉛焊接的效果Wettability testing/ De-wetting 潤(rùn)濕性測(cè)試/縮 錫實(shí)驗(yàn)10 pads per suriace/test/每表面或 測(cè)試有10個(gè)pads With total 40 square solder depots 共4
31、 個(gè)方形焊點(diǎn)41卜 Coppt PadDe-wetting start points/縮錫開(kāi)始站Solder paste printing on a solderable surface/將焊料印在可焊接的表面 Is impacted by surface tension of solder paste and alloy to wetting force/焊料同時(shí)受到自身的表面張力和潤(rùn)濕力的作用De-wetting starts in corners, as surface tension wetting force/當(dāng)表面 張力大于潤(rùn)濕力的時(shí),縮錫現(xiàn)象首先出現(xiàn)在拐角處Sequence/ m
32、echanism similar to SMD reflow soldering on large pads/ 流程和機(jī)理類(lèi)似大pad的SMD回流焊Wettability testing/ De-wetting 潤(rùn)濕性測(cè)試/縮錫實(shí)驗(yàn)Comparison of atmosphere during ageing and soldering/ 當(dāng)寸比老彳匕和焊接時(shí)是否有氮 氣保護(hù)的影響l-Sn 浸;As received 橫老化After 1st reflow 一越流焊後After 2nd reflow 兩疫流焊後After 3rd reflow 三次迴流焊後air nitrogenlAq浸銀HAS
33、L 無(wú)nitrogennitroge nairairade-wettinOSPairn itrogen5 ? l 胡(-eSflw L J No de-wetting for immersion tin/化學(xué)錫沒(méi)有縮錫問(wèn)題N2 improved de-wetting occurrence for the other finishes/對(duì)于其它表 面處理來(lái)說(shuō)氮?dú)獗Wo(hù)降低了縮錫的幾率Wettability testing/ De-wetting 潤(rùn)濕性測(cè)試/縮錫實(shí)驗(yàn) l-Sn/ l-Ag 一 comparison of solder alloys/ paste/ atmosphere 化學(xué)錫化學(xué)金
34、艮表 而處理一對(duì)比不同的焊料組成,焊膏,焊接環(huán)境的影響As received 未經(jīng)老化After 1st reflow 一次迴流焊後NC-SMQ 92HSnPb 63/37 lSnAfter 3rd reflow 三蜩獅後KOKI S3X58M40SnAg3.0Cu0.5 l-SnIndium5.8 LSSn Ag3.0Cu0.5 lSnNo de-wetting for immersion tin/化學(xué)錫沒(méi)有縮錫問(wèn)題Changing solder paste did not improve de-wetting occurrence for I- Ag/對(duì)化學(xué)銀來(lái)說(shuō)改變焊膏並不能降低縮錫的發(fā)
35、生幾率Wettability testing/ De-wetting 潤(rùn)濕性測(cè)試/縮錫 實(shí)驗(yàn)(小結(jié)篇)Impact of paste, alloy and atmosphere on De-wetting test /錫膏合金成份和是 否有氮?dú)獗Wo(hù)對(duì)縮錫測(cè)試的影響Except immersion tin, all surface finishes exhibit strong de-wetting using air atmosphere (immersion silver layer showed de-wetting for the eutectic tin lead and both l
36、ead free soldering paste)/ 除了化學(xué)錫 所有的表面處理在空氣中都有縮錫現(xiàn)象(其中化學(xué)銀無(wú)論是使用錫鉛 焊料還是無(wú)鉛焊料都有縮錫問(wèn)題)All surface showed a noticeable improvement using nitrogen atmosphere /使用氮?dú)獗Wo(hù)對(duì)所有裟面處理都有貢嶽Discoloration was minimized using nitrogen atmosphere /使用氮?dú)獗?護(hù)降低了表面變色問(wèn)題Wettability testing 一 conclusion I 潤(rùn)濕性測(cè)試一結(jié)論一Wetting balance/潤(rùn)錫
37、平衡測(cè)試Wetting times are strongly depending on flux/各種助焊劑對(duì)潤(rùn)濕時(shí)間影Comparable wetting time by using N2 atmospher引使用氮?dú)獗Wo(hù)的無(wú)鉛 焊接儈濕時(shí)間與錫爲(wèi)焊接的潤(rùn)濕瞎間和當(dāng)Solder spread錫料的延伸性Tested paste shows a strong decrease in wetted area/測(cè)試的錫膏潤(rùn)濕 面積明顏減小Mis print/絲印錯(cuò)位試驗(yàn)Comparable results by using N2 atmosphere/使用N?保護(hù)何以得到很好Minimized flow of solder paste after reflow ageing in air/在空氣中老化實(shí) 驗(yàn)后焊膏的流動(dòng)減小Tested pastes shows a strong decrease in wetted area/測(cè)試的錫膏潤(rùn)濕 面積明巔減小De-wetting/縮錫實(shí)驗(yàn)Great improvement by using N2 atmosphere/ 使用氮?dú)獗Wo(hù)有明顯的改 善效果Wettability testing 一 conclusion II潤(rùn)濕性測(cè)試一結(jié)論二For t
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