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白色 asked in 科學工程學 · 1 decade ago



IMC較厚的OSP finish銅墊塑性損傷是較ENIG finish來的低。因此,銅墊的幾何完整性較得以保存,下方材料能受到較均勻的拉力作用,減輕PCB-side兩側角落的應力集中現象。ㄧ般而言銲料中的銀含量越多與所搭配的錫含量就越少,與低銀相比呈現較高剛性的狀態。對於所結合的錫膏(solder paste)成分亦同,且在solder joints附近析出物(precipitation)也會因銀含量的增加而增加。拉伸實驗是以固定拉伸速率牽引元件變形,當拉力足以驅動各材料差排滑移(dislocation slip)或晶界滑移(grain boundary slip)產生塑性變形時,在solder alloys內部precipitation(Ag3Sn或其他相)的多寡將阻礙dislocation可移動程度,形成(析出)強化機制提高合金強度。ENIG的Ni層抑制IMC成長,降低IMC提供給Cu pad的強度而易使其產生塑性變形,拉伸期間銅墊彎曲連代牽引角落RCC層造成損傷;而OSP剛好相反,PCB-side銅墊抵抗拉扯使solder降伏,減輕下方RCC層受角落集中形變影響的程度。

1 Answer

  • 1 decade ago
    Favorite Answer

    IMC thick OSP the finish copper pad plasticity damage compares low which ENIG finish comes. Therefore, the copper pad's geometry integrity can preserve, underneath the material can receive the even pulling force function, reduces the PCB-side both sides corner the stress concentration phenomenon. ㄧ says in the solder the silver content to be more with the tin content which matches are less, compares with the low silver presents the high rigid condition. Regarding tin paste which unifies (solder paste) ingredient also with, because and will separate out thing (precipitation) nearby solder joints also the silver content to increase increases. The stretch experiment is distorts by the fixed stretch speed traction element, when the pulling force actuates sufficiently a various materials difference row of slipping (dislocation slip) or the crystal boundary slipping (grain boundary slip) has the plastic deformation, in solder alloys internal precipitation (Ag3Sn or other) how much will hinder the dislocation transportable degree, forms (separation) to strengthen the mechanism to enhance the alloy intensity. The ENIG Ni level suppresses IMC to grow, reduces IMC to provide to the Cu pad intensity, but Yi Shiqi has the plastic deformation, the stretch period copper pad curving joint tows the corner RCC level to create the damage; But OSP is just opposite, underneath the PCB-side copper pad resistance pulls causes solder to fall bends down, reduces the RCC level the corner centralism deformation influence degree.

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