Raychem Limited

Other

Michael J Ludden

Nicholas J Smith

Peter Nyholm

Paul James Gibney

Richard J Penneck

Patrick J Horner

Polymer (preferably polyimide) sheets with laser ablated through-holes plated with metal are used for making electrical connections to specified microcircuits, especially unbumped microchips and Tape Automated Bonding (TAB) articles. Bonding with different melting-point materials at opposite ends of the plated holes is disclosed. Preferred polyimides are those derived from polymerisation of 4-4'-biphenyldianhydride and (4,4'-diaminobiphenyl, or 4,4'-diaminobiphenylether, or phenylenediamine, preferably p-phenylenediamine).

Uses of uniaxially electrically conductive articles

The present concepts include '1:1' uniax (40) with one conductive through-hole per chip connection site, 'mirror chip' testing, heat-sink bonding to chips, avoiding contact with conductive cleaved edge of chip, indium solid columns, metal recessed (41) in the through-holes. All of these are subject to preferred materials (UPILEX polyimide) and techniques (U.V. laser ablation, minimum taper of holes).

Polymer (preferably polyimide) sheets (10) with laser ablated through-holes plated with metal (20) are used for making electrical conections to specified microcircuits, especially unbumped microchips and Tape Automated Bonding (TAB) articles. Bonding with different melting point materials at opposite ends of the plated holes is disclosed. Preferred polyimides are those derived from polymerisation of 4,4'-biphenyldianhydride and (4,4'-diaminobiphenyl, or 4,4'-diaminobiphenylether, or phylenediamine, preferably p-phenylenediamine).

Laser-machining polymers

Hybrid microchip bonding article

Laminar polymeric sheet

Growing community of inventors

Swindon, United Kingdom

Michael J Ludden