Patent ID: 6291266
Filing Date: 2001-09-18
Classification: H01L

Abstract:
A method for transferring individual circuit elements fabricated on an original semiconductor substrate to arbitrary predetermined locations on a new substrate, said method comprising steps of:(a) providing said original semiconductor substrate with a release member disposed upon a surface of said original semiconductor substrate, said individual circuit elements having been fabricated on top surface of said release member;(b) forming circular individual circuit elements around said individual circuit elements;(c) shaping said circular individual circuit elements in a conical frustum shape;(d) fabricating a first set of metallization contacts on top of smaller circular surface of said conical frustum, said first set of metallization contacts being concentrically disposed rings defining space therebetween;(e) freeing said conical frustum-shaped individual circuit elements by removing said release member;(f) providing a new substrate having conical frustum-shaped individual circuit elements receptors, said receptors having an inside area defined by a curved inside wall, a top circular opening on a surface of said new substrate, and an inside circular surface, said inside circular surface being defined as the bottom of said receptors, said top circular opening being disposed oppositely to said inside circular surface, said top circular opening having a diameter larger than a diameter of said inside circular surface, said receptors having a volume of said inside area larger than a volume of said conical frustum-shaped individual circuit elements;(g) fabricating a second set of metallization contacts on said inside circular surface, said second set of metallization contacts being concentrically disposed rings defining space therebetween, said second set of metallization contacts arranged so as to match said first set of metallization contacts;(h) applying and partially curing an electrically conductive resin inside said receptors so as to cover only said bottom of said receptors;(i) raising said new substrate to an incline, with one end of said new substrate being higher than an opposite end of said new substrate;(j) pouring said freed conical frustum-shaped individual circuit elements onto the higher end of the surface of said new substrate having said receptors followed by shaking said new substrate so that said freed conical frustum-shaped individual circuit elements roll down the inclined new substrate and are trapped inside said receptors and said rings of said first set of metallization contacts being in contact with corresponding rings of said second set of metallization contacts;(k) removing untrapped and/or improperly trapped conical frustum-shaped individual circuit elements that have rolled down to said opposite end of the inclined new substrate from said surface of said new substrate and placing said untrapped conical frustum-shaped individual circuit elements onto said surface of said new substrate;(l) repeating said shaking followed by said step of removing until all said receptors are filled with said conical frustum-shaped individual circuit elements; and(m) completing said curing of said electrically conductive resin inside said receptors.