DUAL SOLDER LAYER FOR FLUIDIC SELF ASSEMBLY AND ELECTRICAL COMPONENT SUBSTRATE AND METHOD EMPLOYING SAME

摘要

Flowable self assembly, dual solder layers for electrical component substrates, and methods of employing them are described. The dual solder layer includes a layer of self-assembly solder disposed on the layer of base solder disposed on the solder pad of the electrical component substrate. The self-assembly solder has a liquidus temperature below the first temperature, and the base solder has a solidus temperature higher than the first temperature. The self-assembly solder liquefies at a first temperature during the flowable self-assembly method to cause electrical components to adhere to the substrate. After attachment, the substrate is removed from the bath and heated to bond the base and self assembly solder to form a composite alloy that forms the final electrical solder connection between the component and the solder pad on the substrate.