Oberflächenmontierbare Halbleitervorrichtung mit selbstbeladenen Lötverbindungen

摘要

An improved semiconductor device( 10) is disclosed having a predetermined amount of solder (36), or other electrically conductive binder adsorbed onto the exterior package leads (18) of the semiconductor device.(10) A de-wettable coating (24) comprising preferably nickel, or alternatively chromium, is plated to a superior portion (34) of the package leads,(18) such that, when the heat is applied to the substrate mounting end (32) of the leads,(18) solder (36) desorbes from the de-wettable layer (24) and flows down the lead (18) to the contact pads (40) on the mounting substrate (42) and forms a solder joint.(46) The amount of solder delivered to the contact pad for joint formation is determined by the thickness of the adsorbed solder layer (36) overlying each package lead.(18) Only enough solder is provided on each lead (18) sufficient to form the joint (46) thus avoiding solder bridging between adjacent contact pads.(40)