Gang bonding interconnect tape for semiconductive devices and method of making same

Abstract

A gang bonding interconnect tape for use in an automatic bonding machine for gang bonding of semiconductive devices is fabricated by depositing a series of electrically insulative support structures, such as rings of epoxy resin, onto a metallic tape, as of copper, there being at least one of said electrically insulative support structures for individual ones of the interconnect lead patterns to be formed in said metallic tape. The side of the metallic tape, opposite to the support structure, is photoetched with a series of interconnect lead patterns with individual ones of said lead patterns being etched in registration with individual ones of said electrically insulative support structures. The individual electrically insulative support structure, preferably in the form of a ring, is located in each of the lead patterns intermediate the central region thereof and the outer region thereof for supporting the individual leads thereof in circumferentially spaced relation.

What is claimed is: 
     
       1. In a method for fabrication of a gang bonding interconnect tape for interconnecting a first pattern of leads and a second pattern of leads, such interconnect tape having a series of metallic interconnectlead patterns thereon, individual ones of said lead patterns including a plurality of ribbon-shaped metallic leads extending outwardly from an inner central portion of said pattern to an outer region of said pattern and including an individual electrically insulative support structure interconnecting a plurality of said ribbon-shaped metallic leads in a region of said pattern intermediate said outer region thereof and said inner central region thereof, the steps of: depositing a series of said individual electrically insulative support structures onto said metallic tape, there being at least one of said individual electrically insulative support structures for individual ones of said interconnect lead patterns to be formed in said metallic tape.   
     
     
       2. The method of claim 1 including the step of, forming a series of said interconnect lead patterns in said metallic tape, individual ones of said lead patterns being formed in registration with individual ones of said electrically insulative support structures so as to locate individual ones of said electrically insulative support structures in a region of individual ones of said lead patterns intermediate said inner central region thereof and said outer region thereof. 
     
     
       3. The method of claim 2 wherein the step of forming said series of said lead patterns in said tape comprises the steps of, coating the side of said tape opposite to said deposited series of electrically insulative support structures with a photoresist coating, exposing the photoresist coating to a series of radiation images each of said images corresponding to individual ones of said interconnect lead patterns to be formed in said tape, removing the photoresist coating in the exposed patterns, and etching the tape in the regions of the removed photoresist coating to form said interconnect patterns therein. 
     
     
       4. The method of claim 2 wherein the step of forming said series of said lead patterns in said tape comprises the steps of, coating the side of said tape opposite to said deposited series of electrically insulative support structures with a photoresist coating, exposing said photoresist coating to parallel rows of radiation images, each of said images corresponding to individual ones of said interconnect patterns to be formed in said tape, removing the photoresist coating in the exposed patterns, and etching said tape in the regions of the removed photoresist coating to form rows of interconnect patterns therein. 
     
     
       5. The method of claim 4 including the step of slitting said tape in the regions thereof between and parallel to said rows of interconnect patterns to slit the tape into a plurality of tapes each having a row of said interconnect patterns thereon. 
     
     
       6. The method of claim 4 including the step of, punching a series of locator holes in said tape prior to the step of exposing said tape to said rows of radiation images. 
     
     
       7. The method of claim 4 wherein said step of exposing said tape to said rows of interconnect patterns includes the step of, exposing said tape to rows of radiation images corresponding to rows of locator holes to be formed in said tape there being at least one such row of locator hole images for each row of interconnect pattern images, and wherein the step of etching the tape includes, etching said rows of locator hole images to form at least one row of locator holes for each row of said interconnect patterns formed in said tape. 
     
     
       8. The method of claim 1 wherein the step of depositing said series of electrically insulative support structures on said metallic tape includes the step of, depositing a series of individual electrically insulative support rings on said tape to serve as said series of support structures. 
     
     
       9. The method of claim 1 wherein said tape is elongated and wherein the step of depositing said series of electrically insulative support structures on said metallic tape includes the step of, depositing rows of said electrically insulative support structures on said tape, said rows extending generally in the direction of elongation of said tape. 
     
     
       10. The method of claim 1 wherein said tape is made of copper. 
     
     
       11. The method of claim 1 wherein said step of depositing said series of electrically insulative support structures on said tape comprises the step of, flowing an electrically insulative material through a patterned screen onto said tape as a series pattern of electrically insulative portions, and allowing the electrically insulative patterns to harden into said series of electrically insulative support structures. .Iadd.12. A method of producing a metal-plastic composite lead frame device for integrated circuit packaging, said lead frame device having a plurality of cantilever metal leads held in fixed alignment near their free ends by a member of plastics material, comprising the steps of: perforating a continuous web of metallic foil with a plurality of accurately spaced registration apertures along at least one marginal edge thereof;   depositing on a first side of said foil a pattern of thin, electrically insulating plastic meterial accurately aligned with respect to said apertures, said pattern having lesser overall dimensions than said web;   coating the opposite side of said foil with a photoresist material;   imaging a lead frame pattern on said photoresist at accurately aligned positions with respect to said apertures;   developing said imaged lead frame pattern; and   passing said strip through an etching bath whereby said strip will be etched away leaving only a lead frame with the leads supported by said   
     
     
        plastics material. .Iaddend. .Iadd.13.  A method according to claim 12 wherein said pattern of electrically insulating plastic material is printed on said metal foil and has a thickness in the range of 0.5 to 2 mils. .Iaddend. .Iadd.14. A method according to claim 12 wherein said pattern of electrically insulating plastic material is preformed and bonded to said metal foil. .Iaddend. .Iadd.15. A method according to claim 12 wherein said plastic material is selected from the group including polyimides and epoxies. .Iaddend. .Iadd.16. A method according to claim 12 wherein said metallic foil is copper having a thickness in the range of 1.3 to 2.6 mils. .Iaddend.