首页>
外国专利>
Direct IMS (injection molded solder) without a mask for forming solder bumps on substrates
Direct IMS (injection molded solder) without a mask for forming solder bumps on substrates
展开▼
机译:不带掩模的直接IMS(注塑焊料),用于在基板上形成焊料凸点
展开▼
页面导航
摘要
著录项
相似文献
摘要
An assembly is obtained; it includes a substrate; a plurality of wet-able pads formed on a surface of the substrate; and a solder resist layer deposited on the surface of the substrate and having an outer surface. At least the solder resist layer is formed with recessed regions defining volumes adjacent the wet-able pads. Molten solder is directly injected into the volumes adjacent the wet-able pads, such that the volumes adjacent the wet-able pads are filled with solder. The solder is allowed to solidify. It forms a plurality of solder structures adhered to the wet-able pads. The substrate and the solder are re-heated after the solidification, to re-flow the solder into generally spherical balls extending above the outer surface of the solder resist layer. The volumes adjacent the wet-able pads are configured and dimensioned to receive sufficient solder in the injecting step such that the generally spherical balls extend above the outer surface of the solder resist layer as a result of the re-heating step. In an alternative approach, solder injection and solidification are carried out in a nitrogen environment or a forming gas environment, and the reflow step may be omitted.
展开▼