Process for manufacturing a multi-layer lead frame

Abstract

A process for manufacturing a multi-layer lead frame for a semiconductor device comprises two metal plains being adhered to each other via an insulation piece. An insulation strip is punched to cut the insulation piece, which is preliminary adhered to a metal strip. The metal strip is then punched to cut and remove the metal plane, which is then laminated and heat-pressed to another metal strip. After completely adhered, the other metal strip is punched to remove a multi-layer lead frame.

We claim: 
     
       1. A process for manufacturing a multi-layer lead frame for a semiconductor device comprising a lead frame body and at least one metal plane adhered to said lead frame body by means of an insulation tape piece, said process comprising the following steps of: forming a lead frame strip and at least one metal plane strip from metal strips, said lead frame strip comprising, a first supporting frame and a plurality of lead frame base longitudinally and continuously arranged, said metal plane strip comprising a plurality of said metal planes longitudinally and continuously arranged and connected to each other by connecting portions, and supported by said first supporting frame and having positioning means;   forming at least one insulation tape strip from a resin strip providing adhesive layers on its respective surfaces, said insulation tape strip comprising a plurality of said insulation tape pieces longitudinally and continuously arranged and connected to another supporting frame via other connecting portions, said other supporting frame having positioning means;   positioning said insulation tape strip with respect to said metal plane strip by their positioning means;   punching said insulation tape strip to cut and remove at least one of said insulation tape pieces from said other connecting portions and provisionally adhering said insulation tape piece to at least one of said metal planes of said metal plane strip;   positioning said metal plane strip with respect to said lead frame strip; and   punching said metal plane strip to cut and remove said at least one metal plane from said connecting portions and laminating by heat-pressing in order to completely adhere to said metal plane to said at least one lead frame base of said lead frame strip.   
     
     
       2. A process as set forth in cIaim 1, wherein said metal plane comprises two layers consisting of a power supply plane and a ground plane. 
     
     
       3. A process as set forth in claim 2 further comprising the steps of: punching a first insulation tape strip to cut and remove at least one of first insulation tape pieces and provisionally adhering said first insulation tape piece to at least one power supply plane of a power supply plane strip; and,   punching a second insulation tape strip to cut and remove at least one of second insulation tape pieces and provisionally adhering said second insulation tape piece to at least one ground plane of the ground plane strip.   
     
     
       4. A process as set forth in claim 3 further comprising the steps of: punching said power supply plane strip to cut and remove said at least one power supply plane and laminating by heating-pressing said power supply plane to provisionally adhere said power supply plane to said at least one lead frame base of said lead frame strip; and   punching said ground plane strip to cut and remove said at least one ground plane and laminating by heat-pressing said ground plane to said power supply plane already adhered to said lead frame base in order to adhere said ground plane to said power supply plane and said lead frame base.   
     
     
       5. A process as in claim 1 wherein said positioning means comprises guide holes. 
     
     
       6. A process for manufacturing a multi-layer lead frame for a semiconductor device comprising a lead frame body and at least one metal plane adhered to said lead frame body by means of an insulation tape piece, said process comprising the following steps of: forming a lead frame strip and at least one metal plane strip from metal strips, said lead frame strip comprising a plurality of lead frame bases longitudinally and continuously arranged, said metal plane strip comprising a plurality of said metal planes longitudinally and continuously arranged and connected to a supporting frame via connecting portions, and said supporting frame having positioning means:   forming insulation tape strips from resin strips each providing adhesive layers on its respective surfaces, each of said insulation tape strips comprising a plurality of said insulation tape pieces longitudinally arranged and continuously connected to another supporting frame via other connecting portions, said other supporting frame having positioning means:   positioning said lead frame strip, said metal plane strip, and said insulation tape strips, respectively, by said positioning means;   punching said insulation tape strips to cut and remove the insulation tape pieces from said another connecting portions and provisionally adhering said insulation tape pieces to predetermined positions of said lead frame strip and/or said metal plane strip;   positioning and laminating by heat-pressing said lead frame strip and said metal plane strip to completely adhere them together via said insulation tape pieces; and separating said metal planes from their supporting frames.   
     
     
       7. A process as set forth in claim 6, wherein said metal plane comprises two layers consisting of a power supply plane and a ground plane, and said lead frame body, said power supply plane and said ground plane are laminated in this order. 
     
     
       8. A process in claim 6 wherein said positioning means comprises guide holes. 
     
     
       9. A process for manufacturing a multi-layer lead frame for a semiconductor device comprising at least two metal planes adhered to each other by means of an insulation tape piece, said process comprising the following steps of: forming at least two metal strips each comprising a plurality of said metal planes longitudinally and continuously arranged and having positioning means;   forming at least one insulation tape strip providing adhesive layers on its respective surfaces, said insulation tape strip comprising a plurality of said insulation tape pieces longitudinally and continuously arranged an having positioning means;   positioning said insulation tape strip with respect to a first metal plane strip by their positioning means; punching said insulation tape strip to cut and remove said insulation tape piece and provisionally adhering said insulation tape piece to said first metal plane strip;   positioning said first metal plane strip with respect to a second metal plane strip;   punching said first metal plane strip to cut and remove a first metal plane and laminating by heat-pressing to completely adhere said first metal plane to said second metal plane strip; and,   punching said second metal plane strip to cut and remove a second metal plane.   
     
     
       10. A process as in claim 9 wherein said positioning means comprises guide holes. 
     
     
       11. A process for manufacturing a multi-layer lead frame for a semiconductor device comprising at least two metal planes adhered to each other by means of an insulation tape piece, said process comprising the following steps of: forming at least two metal strips each comprising a plurality of said metal planes longitudinally and continuously arranged and having positioning means;   forming at least one insulation tape strip providing adhesive layers on is respective surfaces, said insulation tape strip comprising a plurality of said insulation tape pieces longitudinally and continuously arranged and having positioning means;   positioning said insulation tape strip with respect to a first metal plane strip by their positioning means;   punching said insulation tape strip to cut and remove said insulation tape piece and provisionally adhering said insulation tape piece to said first metal plane strip;   positioning said first metal plane strip with respect to a second metal plane strip; and,   laminating by heat-pressing said first metal plane strip to said second metal plane strip to completely adhere them to each other.   
     
     
       12. A process as in claim 11 wherein said positioning means comprises guide holes.