发明名称 |
Solder retention ring for improved solder bump formation |
摘要 |
A method of forming solder bumps on a wafer. The wafer includes at least one substrate, a plurality of solder-wettable pads and a solder wettable retention ring about the periphery of the wafer. The method of forming solder bumps includes forming a non-solder-wettable mask on the wafer which includes a plurality of apertures which align with the solder-wettable pads, and the solder wettable retention ring surrounds the mask. The mask and wafer are positioned within an aperture of a stencil so that the solder wettable retention ring aligns with a gap between the periphery edge of the mask and an inside edge of the aperture of the stencil. Solder paste is applied to the mask so that the solder paste fills the apertures of the mask and the gap. The solder paste is reflowed forming solder bumps on the pads and a solder ring on the solder wettable retention ring. The mask is removed after formation of the solder bumps.
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申请公布号 |
US6085968(A) |
申请公布日期 |
2000.07.11 |
申请号 |
US19990235579 |
申请日期 |
1999.01.22 |
申请人 |
HEWLETT-PACKARD COMPANY |
发明人 |
SWINDLEHURST, SUSAN J.;VANDER PLAS, HUBERT A.;LEIBOVITZ, JACQUES |
分类号 |
B23K3/06;B23K35/14;H01L21/60;(IPC1-7):B23K35/14;B23K31/02;H01L21/441 |
主分类号 |
B23K3/06 |
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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