发明名称 |
Solder hierarchy for lead free solder joint |
摘要 |
A lead free solder hierarchy for use in the second level solder connection of electronic components such as joining an electronic module to a circuit board. An off-eutectic solder concentration of SnCu or SnAg is used for the module side connection. This off-eutectic solder contains sufficient intermetallics to provide the module side connection with a robust second level assembly and rework process. The off-eutectic composition provides an inter-metallic phase structure in the module side fillet during assembly. The inter-metallic phase structure eliminates problems of tilt and collapse during second level assembly and aids in rework by providing a more cohesive joint allowing removal of the columns from the board without simultaneous removal from the module.
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申请公布号 |
US2004050904(A1) |
申请公布日期 |
2004.03.18 |
申请号 |
US20020246282 |
申请日期 |
2002.09.18 |
申请人 |
INTERNATIONAL BUSINESS MACHINES CORPORATION |
发明人 |
INTERRANTE MARIO;FAROOQ MUKTA G.;SABLINSKI WILLIAM |
分类号 |
B23K1/00;B23K35/14;B23K35/26;B23K101/40;B23K101/42;C22C13/00;H05K3/34;(IPC1-7):B23K35/14 |
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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