发明名称 |
Lead-free solder structure and method for high fatigue life |
摘要 |
A method and structure for solderably coupling an electronic module (e.g. a ceramic or plastic ball grid array module) to a circuit board. A lead-free solder ball is soldered to the module without using a joining solder to effectuate the soldering. The solder ball comprises a tin-antimony alloy that includes about 3% to about 15% antimony by weight. The solder ball is soldered to the circuit board with a lead-free joiner solder. The joiner solder comprises a tin-silver-copper alloy that includes by weight about 95.5-96.0% tin, about 3.5-4.0% silver, and about 0.5-1.0% copper. The resultant solder connection between the module and the circuit board has a fatigue life of at least about 90% of a fatigue life of a reference structure. The reference structure has a 90Pb/10Sn solder ball joined to both the module and the circuit card by a 63Sn/37Pb joiner solder. |
申请公布号 |
US6784086(B2) |
申请公布日期 |
2004.08.31 |
申请号 |
US20010779812 |
申请日期 |
2001.02.08 |
申请人 |
INTERNATIONAL BUSINESS MACHINES CORPORATION |
发明人 |
RAY SUDIPTA K.;SARKHEL AMIT K. |
分类号 |
B23K1/00;B23K35/02;B23K35/14;B23K35/26;H01L21/60;H01L23/485;H01L23/488;H01L23/498;H05K3/34;(IPC1-7):H01L21/44 |
主分类号 |
B23K1/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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