共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
3.
4.
5.
针对2.5D立体封装中热膨胀系数及结构尺寸均存在较大差异、极易在热应力作用下产生热疲劳失效的可靠性问题,开展多芯片硅基集成封装互连界面温度循环加速试验,并基于Weibull分布对2.5D封装互连界面热适配性能进行评估分析,实现了2.5D封装可靠性指标的评估和失效率鉴定方案的制定. 相似文献
6.
7.
8.
文章以一款实用高性能CPU的2.5D封装有机基板为研究对象,对有机基板制备的工艺流程、关键技术难点进行了详细实验和讨论,最终完成了合格样板的制作,并形成小批量产晶的生产能力。 相似文献
9.
10.
11.
12.
13.
采用Sn0.45A g0.68Cu亚共晶无铅钎料通过热浸焊获得铜接头,在-45~125℃的温度循环区间内对焊接接头进行200、400、600、800、1000周期高低温热冲击循环实验,分析了焊点的剪切强度变化,组织演变及界面IM C的生长规律。结果表明:焊点组织中弥散分布的Cu6Sn5相内部晶粒逐渐粗化长大,最后转变为圆形或者椭圆形;焊点界面IM C层厚度明显增厚,且由最初的细小扇贝状转变为大的波浪状,最终趋于平缓;焊点的剪切强度随热冲击循环周期的增加而急剧下降,经400周期的热冲击循环之后,焊点的剪切强度已下降了约22.5%,在400周期的热冲击循环后开始变得平缓,最后趋于稳定。 相似文献
14.
The electronic packaging industry uses electroless nickel immersion gold (ENIG) or Cu-organic solderability preservative (Cu-OSP)
as a bonding pad surface finish for solder joints. In portable electronic products, drop impact tests induce solder joint
failures via the interfacial intermetallic, which is a serious reliability concern. The intermetallic compound (IMC) is subjected
to thermal cycling, which negatively affects the drop impact reliability. In this work, the reliability of lead-free Sn-3.0Ag-0.5Cu
(SAC) soldered fine-pitch ball grid array assemblies were investigated after being subjected to a combination of thermal cycling
followed by board level drop tests. Drop impact tests conducted before and after thermal aging cycles (500, 1000, and 1500
thermal cycles) show a transition of failure modes and a significant reduction in drop durability for both SAC/ENIG and SAC/Cu-OSP
soldered assemblies. Without thermal cycling aging, the boards with the Cu-OSP surface finish exhibit better drop impact reliability
than those with ENIG. However, the reverse is true if thermal cycle (TC) aging is performed. For SAC/Cu-OSP soldered assemblies,
a large number of Kirkendall voids were observed at the interface between the intermetallic and Cu pad after thermal cycling
aging. The void formation resulted in weak bonding between the solder and Cu, leading to brittle interface fracture in the
drop impact test, which resulted in significantly lower drop test lifetimes. For SAC/ENIG soldered assemblies, the consumption
of Ni in the formation of NiCuSn intermetallics induced vertical voids in the Ni(P) layer. 相似文献
15.
16.
粘结层空洞对功率器件封装热阻的影响 总被引:1,自引:0,他引:1
功率器件的热阻是预测器件结温和可靠性的重要热参数,其中芯片粘接工艺过程引起的粘结层空洞对于器件热性能有很大的影响。采用有限元软件Ansys Workbench对TO3P封装形式的功率器件进行建模与热仿真,精确构建了不同类型空洞的粘结层模型,包括不同空洞率的单个大空洞和离散分布小空洞、不同深度分布的浅层空洞和沿着对角线分布的大空洞。结果表明,单个大空洞对器件结温和热阻升高的影响远大于相同空洞率的离散小空洞;贯穿粘结层的空洞和分布在芯片与粘结层之间的浅空洞会显著引起热阻上升;分布在粘结层边缘的大空洞比中心和其他位置的大空洞对热阻升高贡献更大。 相似文献
17.
通过对共晶锡铅焊料和PCB UBM层电镀薄金焊盘反应后的界面微观组织观察和焊点断口力学性能分析,系统研究了PCB焊盘薄金对焊点焊接性能的影响。结合Au-Sn合金二元相图理论和Au在Sn中溶解速率,研究结果显示在一定应用场合,利用薄金焊盘可避免搪锡去金工艺,可有效地提高生产效率且无可靠性风险。 相似文献
18.
将功率循环方法应用于大功率LED焊料层的可靠性研究,对比分析了在650 mA,675 mA和700 mA电流条件下大功率LED焊料层的热阻退化情况。实验结果表明,循环达到一定次数,大功率LED热阻才开始退化,并呈线性增加,从而引起光通量下降;另外,失效循环次数与电流值之间呈线性关系,并外推出正常工作条件下焊料层寿命为90 968次。对样品进行了超声波检测(C-SAM),发现老化后LED焊料层有空洞形成,这说明空洞是引起热阻升高的主要原因。 相似文献
19.
In solder ball grid array (BGA) technology, solder joint reliability is one of the critical issues in microelectronics manufacturing industries. In this reliability aging study, Sn3.5AgO.7Cu solder joints were subjected to accelerated temperature cycling (ATC) test in TBGA assembly. Fatigue fracture occurred, very close to the solder/intermetallic compound (IMC) interface, at the TBGA component side due to the larger coefficient of thermal expansion (CTE) mismatch compared to the PCB side. During reflow, needle-type and scallop-type morphologies of (Cu,Ni)6Sn5 IMCs were formed at the TBGA component and PCB interfaces. In the process of thermal cycling, a layer of (Ni,Cu)3Sn4 IMC grew beneath the (Cu,Ni)6Sn5 IMC due to the out diffusion of Ni from the under bump metallization (UBM). After extended thermal cycling aging, Ni-Sn-P IMC was found between the (Ni,Cu)3Sn4 IMC and the In3P layer at the printed circuit board (PCB) interface. Grain ripening and spalling of (Cu,Ni)6Sn5 IMC grains into the solder joint was also observed in the process of thermal cycling. The spalling phenomena of (Cu,Ni)6Sn5 IMCs was caused by interface structure change and cyclic shear stresses and strains incurred during temperature cycling. 相似文献
20.
The work reported here concerns the creep of pure Sn solder joints with Cu metallization (Cu||Sn||Cu). Steady-state creep tests in shear are combined with electron backscatter diffraction (EBSD) analysis of the evolution of the microstructure during creep to clarify the deformation mechanism and the nature of the microstructural evolution. The creep behavior of the joint changes significantly with temperature. At low temperature (65°C), two distinct creep mechanisms are observed. Low-stress creep is apparently dominated by grain boundary sliding, as evidenced by the low stress exponent (n ≈ 4), low activation energy (Q ≈ 42 kJ/mole), and significant grain rotation during creep. High-stress creep is dominated by bulk deformation processes, evidenced by a high stress exponent (n ≈ 9), an activation energy like that for bulk diffusion (Q ≈ 70 kJ/mole), and a relatively fixed microstructure. At high temperature all aspects of its behavior are consistent with deformation by bulk creep mechanisms; the stress exponent and activation energy are high (n ≈ 5 to 7, Q ≈ 96 kJ/mole), and despite significant grain coarsening, the microstructure retains (and strengthens) a fixed [001] texture. The results suggest that a “segmented” constitutive equation of Dorn type is most suitable for the low-temperature behavior, while a “hyperbolic” constitutive equation may be preferable at high temperature. 相似文献