Flexible printed circuit board having integrated circuit die or the like affixed thereto

• US 4,677,528 A
• Filed: 01/27/1986
• Issued: 06/30/1987
• Est. Priority Date: 05/31/1984
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Miniet, Jay J.
• Primary Examiner(s): Kucia, R. R.
• Application Number:
  US06/822,935
• Time in Patent Office: 519 Days
• Field of Search: 361/398, 361/401, 361/414, 361/394, 361/395, 361/399, 361/415, 361/395, 361/914, 235/488, 235/492
• US Class Current: 361/751
• CPC Class Codes: H01L 2224/2612 Auxiliary members for layer connectors, e.g. spacers
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48472 the other connecting portion not on the bonding area also being a wedge bond, i.e. wedge-to-wedge
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 23/5387 Flexible insulating substrates H01L23/5388 takes precedence
• CPC Class Codes: H01L 24/32 of an individual layer connector
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01029 Copper [Cu]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01082 Lead [Pb]
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/15153 the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/1517 : Multilayer substrate
• CPC Class Codes: H01L 2924/16195 : Flat cap [not enclosing an internal cavity]

Abstract

A flexible printed circuit board assembly having an integrated circuit die bonded directly thereto. A first layer of the flexible printed circuit board assembly includes a plurality of conductive paths and geometrical patterns on each of its surfaces. The conductive patterns include pads for mounting the integrated circuit die and connecting the wires from the integrated circuit. Additional intermediate layers of the flexible printed circuit board assembly, having an aggregate thickness greater than the height of the integrated circuit die and associated leads bonded thereto, surround the integrated circuit die. The top layer of the flexible printed circuit board provides for total encapsulation of the integrated circuit die for protection thereof. In the preferred embodiment that portion of the top layer which covers the integrated circuit die is opaque to prevent the passage of ultraviolet light which might otherwise cause damage to the integrated circuit.

Claims

1. A flexible circuit board assembly, suitable for insertion into a protective housing, said flexible circuit board assembly comprising in combination:

a first flexible layer having a printed circuit geometrical pattern;

first and second integrated circuit dies bonded respectively to first and second areas of said first flexible layer, said dies being electrically connected to said printed circuit pattern;

first and second intermediate layers each having an opening for respectively receiving said first and second dies, each of said intermediate layers having first and second surfaces wherein each of said first surfaces is bonded to said first flexible layer and each of said second surfaces respectively extends beyond said first and second dies, said first and second intermediate layers being separated by a gap; and

first and second cover layers respectively bonded to said second surface of said first and second intermediate layers, thereby encapsulating said first and second dies;

whereby said assembly can be folded along said gap and inserted into said protective cover.

2. The flexible circuit board assembly, according to claim 1, wherein one of said cover layers includes a sheet of opaque polyimide film, thereby protecting one of said integrated circuit die from ultra-violet light.

3. The flexible circuit board assembly of claim 1, wherein each intermediate layer includes a plurality of sheets of polyimide film bonded to one another.