Molded plating mask

• US 4,404,080 A
• Filed: 03/22/1982
• Issued: 09/13/1983
• Est. Priority Date: 03/22/1982
• Status: Expired due to Term

• Current Assignee: Fairchild Semiconductor Corporation (ON Semiconductor Corporation)
• Original Assignee: National Semiconductor Corporation (Texas Instruments, Inc.)
• Inventors: Jahani, Hooshang
• Primary Examiner(s): Tung, T.
• Assistant Examiner(s): Thane, Nathan S.
• Application Number:
  US06/360,742
• Time in Patent Office: 540 Days
• Field of Search: 204/15, 204/224, 204/279, 106/38.2, 264/255
• US Class Current: 204/224.00R
• CPC Class Codes: C25D 5/02 Electroplating of selected surface areas
• CPC Class Codes: H05K 3/202 using self-supporting metal foil pattern
• CPC Class Codes: H05K 3/241 characterised by the electroplating method; means therefor, e.g. baths or apparatus
• CPC Class Codes: H05K 3/243 characterised by selective plating, e.g. for finish plating of pads selective plating for making the circuit pattern H05K3/108, H05K3/182

Abstract

A plating mask of molded unitary configuration with electrolyte admitting openings held to very accurate position and dimension by a molding process in which the mask is formed between two separable molds with forms supported therebetween to exclude material from both mask penetrating and transverse circulation passageways.

Claims

1. A plating mask having a first resilient layer forming a sealing face for facing contact with a surface to be plated, a backing structure supporting said sealing face, said backing structure comprising first and second planar rigidizing support members with a second resilient layer therebetween, first electrolyte fluid passageways extending through said first and second planar support members and said second resilient layer and said sealing face, to selected areas of said surface, second electrolyte passageways in said second resilient layer generally transverse to, and in communication with, said first passageways, said plating mask formed by the process of molding a resilient material between front and back molds held apart by removable spacers, said front and back molds containing therebetween first and second forms to exclude said resilient material from the passageways, the first forms creating said first passageways and being mounted on said front mold and the second forms creating said passageways and being held in place by being fastened in the first forms, said second planar support member being disposed between said first and second forms.

2. The mask of claim 1 in which said removable spacers are disposed between said front and back molds and about the perimeter of said front and back molds so as to enclose the space between the molds and contain said resilient material therein.

3. A plating mask having a sealing face for facing contact with a surface to be plated, a backing structure supporting said sealing face, first electrolyte fluid passageways extending from and through said backing structure, through said sealing face, to selected areas of said surface, second electrolyte passageways inside said backing structure generally transverse to, and in communication with, said first passageways, said plating mask including a rigidizing planar member parallel to and behind said sealing face with apertures therein corresponding in location to said first passageways, the edges of said apertures extending inwards toward the first passageways farther than the edges of the corresponding opening in the sealing face so as to help prevent said sealing face from curling over the edge of the planar member and into said first passageway.

4. The process of forming a plating mask having a sealing face for facing contact with a surface to be plated, a backing structure supporting said sealing face, first electrolyte fluid passageways extending from and through said backing structure, through said sealing face, to selected areas of said surface, second electrolyte passageways inside said backing structure generally transverse to, and in communication with, said first passageways, comprising the steps of molding material on a mold to form said sealing face, placing a rigidizing member thereon, placing spacers about the perimeter of the mold to contain said material, placing inserts on said rigidizing member to exclude molding material from the passageways, adding more molding material, adding an additional rigidizing member to the assembled components, and curing the molding material into a resilient integrated structurally supporting continuous medium throughout said plating mask.