Patent ID: 6098280
Filing Date: 2000-08-08
Classification: H01L,H05K,Y10T

Abstract:
A process of forming a multi-layer electronic composite structure, said process comprising the steps of:a) providing at least one core including at least one plane of at least one electrically conducting material with a plane of at least one electrically insulating material on both sides of the at least one plane of at least one electrically conducting material, said at least one core including a plurality of plated through holes formed therethrough plated with an electrically conducting material; andb) providing a plurality of pads of an electrically-conducting material over a plurality of said plated through holes, each of said pads providing a flat surface for attaching an electronic device, each of said pads also preventing solder from entering said plurality of plated through holes and providing a direct electrical connection between said electronic device and said at least one core, said pads being physically isolated from each other,wherein said pads are formed by:a) forming a panel by providing a plane of an electrically conducting material including a top surface and a bottom surface;b) depositing a first layer of photosensitive material on said top and bottom surfaces of said electrically conducting plane;c) exposing said first layer of photosensitive material on said bottom surface of said electrically conducting plane to radiation, said radiation causing photochemical reactions to occur within said first layer of photosensitive material, said bottom surface being exposed in a pattern matching a pattern of plated through holes formed in said at least one core;d) exposing all of said first layer of photosensitive material to radiation on said top surface of said electrically conducting plane;e) removing portions of said first layer of photosensitive material not exposed to said radiation;f) depositing an electrically conducting material on portions of said electrically conducting material exposed by removing portions of said first layer of photosensitive material not exposed to said radiation;g) removing all remaining portions of said first layer of photosensitive material from said electrically conducting plane;h) aligning said electrically conducting material deposited on said electrically conducting plane with said plated through holes on said core;i) joining said plane to said at least one core by laminating said bottom surface of said plane to said core;j) depositing a second layer of photosensitive material on said top surface of said plane;k) exposing selected portions of said second layer of photosensitive material on said top surface of said panel to radiation, said radiation causing photochemical reactions to occur within said second layer of photosensitive material;l) developing said second layer of photosensitive material to remove portions of said second layer of photosensitive material;m) depositing an electrically conducting material where the portions of the second layer of photosensitive material were removed;n) removing the remaining portions of the second layer of photosensitive material; ando) etching said electrically conducting plane of said panel.