LOC semiconductor assembled with room temperature adhesive

• US 5,840,598 A
• Filed: 08/14/1997
• Issued: 11/24/1998
• Est. Priority Date: 08/14/1997
• Status: Expired due to Term

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Farnworth, Warren M., Grigg, Ford B.
• Primary Examiner(s): Niebling, John
• Assistant Examiner(s): Jones, Josetta I.
• Application Number:
  US08/916,977
• Time in Patent Office: 467 Days
• Field of Search: 438/118, 438/611, 438/366, 438/106, 156/326, 156/335
• US Class Current: 438/118
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/32014 the layer connector being smaller than the bonding area, e.g. bond pad
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48 of an individual wire connector
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/4824 Connecting between the body and an opposite side of the item with respect to the body
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/4826 Connecting between the body and an opposite side of the item with respect to the body
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/73215 Layer and wire connectors
• CPC Class Codes: H01L 2224/743 Apparatus for manufacturing layer connectors
• CPC Class Codes: H01L 2224/83 using a layer connector
• CPC Class Codes: H01L 2224/83101 as prepeg comprising a layer connector, e.g. provided in an insulating plate member
• CPC Class Codes: H01L 2224/83192 wherein the layer connectors are disposed only on another item or body to be connected to the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/8385 using a polymer adhesive, e.g. an adhesive based on silicone, epoxy, polyimide, polyester
• CPC Class Codes: H01L 2224/85 using a wire connector
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 2224/92 Specific sequence of method steps
• CPC Class Codes: H01L 2224/92147 : the second connecting process involving a wire connector
• CPC Class Codes: H01L 2224/92247 : the second connecting process involving a wire connector
• CPC Class Codes: H01L 23/4951 : Chip-on-leads or leads-on-chip techniques, i.e. inner lead fingers being used as die pad
• CPC Class Codes: H01L 23/49513 : having bonding material between chip and die pad
• CPC Class Codes: H01L 24/27 : Manufacturing methods
• CPC Class Codes: H01L 24/28 : Structure, shape, material or disposition of the layer connectors prior to the connecting process
• CPC Class Codes: H01L 24/29 : of an individual layer connector
• 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 24/743 : Apparatus for manufacturing layer connectors
• CPC Class Codes: H01L 24/83 : using a layer 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 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/078 : Adhesive characteristics other than chemical
• CPC Class Codes: H01L 2924/07802 : not being an ohmic electrical conductor
• CPC Class Codes: H01L 2924/12044 : OLED
• CPC Class Codes: H01L 2924/207 : Diameter ranges
• CPC Class Codes: Y10T 428/24207 : with strand[s] or strand-portion[s] between layers [e.g., upholstery trim, etc.]

Abstract

A semiconductor device assembly has a lead frame and a semiconductor device configured to be attached to each other. An adhesive is applied at room temperature through a stencil to the lead frame. The semiconductor device is urged against the adhesive to effect the attachment between the semiconductor device and the lead frame. The adhesive preferably is from about 75 percent to about 95 percent isobutyl acetal diphenol copolymer and from about 25 percent to about 5 percent, respectively, of titanium oxide.

Claims

1. A method of assembling a semiconductor device assembly, said method comprising:

providing a lead frame having a plurality of lead fingers thereon, at least one lead finger of said plurality of lead fingers having an attaching surface;

providing a semiconductor device having an active surface having at least one bond pad thereon configured for electrical connection to said at least one lead finger of said plurality of lead fingers of said lead frame;

selecting a non-conductive polymer adhesive from a group of copolymers that includes isobutyl compounds;

applying said non-conductive polymer adhesive to one of said active surface of said semiconductor device and said attaching surface of said at least one lead finger of said plurality of lead fingers of said lead frame;

retaining said semiconductor device, said lead frame, and said non-conductive polymer adhesive at room temperature;

urging said active surface of said semiconductor device and said attaching surface of said at least one lead finger of said plurality of lead fingers of said lead frame together at room temperature to attach said semiconductor device and said at least one lead finger of said plurality of lead fingers of said lead frame together, thereby effecting connection between said attaching surface of said at least one lead finger of said plurality of lead fingers of said lead frame and said active surface of said semiconductor device.

2. The method of claim 1, wherein a first portion of said non-conductive polymer adhesive is isobutyl acetal diphenol copolymer.

3. The method of claim 1, wherein said non-conductive polymer adhesive includes a first material from a group of copolymers that includes isobutyl acetal diphenol copolymer and a second material that is from a group of metal oxides that includes titanium dioxide.

4. The method of claim 3, wherein said non-conductive polymer adhesive has from about 75 percent to about 95 percent by weight of isobutyl acetal diphenol copolymer and from about 25 percent to about 5 percent by weight, respectively, of titanium dioxide.

5. A method of assembling a semiconductor device assembly, said method comprising:

providing a lead frame having an attaching surface;

providing a semiconductor device having an active surface having at least one bond pad thereon configured for electrical connection to said lead frame;

selecting a non-conductive polymer adhesive which includes a first material from a group of copolymers that includes isobutyl acetal diphenol copolymer and a second material that is from a group of metal oxides that includes titanium dioxide;

applying said non-conductive polymer adhesive to one of a portion of said active surface of said semiconductor device and said attaching surface of said lead frame;

retaining said lead frame, said semiconductor device, and said non-conductive polymer adhesive at room temperature; and

urging said active surface of said semiconductor device and said attaching surface of said lead frame together to attach said semiconductor device and said lead frame together, thereby effecting connection between said attaching surface of said lead frame and said active surface of said semiconductor device.

6. A method of assembling a semiconductor device assembly, said method comprising:

providing a lead frame having a plurality of lead fingers, each lead finger of said plurality of lead fingers having an attaching surface;

providing a semiconductor device having an active surface having a plurality of bond pads located thereon configured for electrical connection to said plurality of lead fingers of said lead frame;

selecting an adhesive that includes from about 75 percent to about 95 percent of isobutyl acetal diphenol copolymer and from about 25 percent to about 5 percent, respectively, of titanium dioxide;

applying said adhesive to one of said active surface of said semiconductor device and said attaching surface of each lead finger of said plurality of lead fingers of said lead frame;

retaining said semiconductor device, said lead frame, and said adhesive at room temperature; and

urging said active surface of said semiconductor device and said attaching surfaces of said plurality of lead fingers of said lead frame together at room temperature to attach said semiconductor device and said lead frame together, thereby effecting connections between said attaching surfaces of said lead fingers of said plurality of lead fingers of said lead frame and said portions of active surface of said semiconductor device.

7. A method of assembling a semiconductor device assembly, said method comprising:

providing a lead frame having an attaching surface;

providing a semiconductor device having a plurality of bond pads located on an active surface thereof configured for electrical connection to said lead frame;

providing a stencil;

forming a selected pattern in said stencil;

selecting a non-conductive polymer adhesive from a group of copolymers that includes isobutyl compounds and is applicable to a substrate through a stencil;

positioning said stencil and one of said attaching surface of said lead frame and said active surface of said semiconductor device relative to each other;

applying said non-conductive polymer adhesive to one of said active surface of said semiconductor device and said attaching surface of said lead frame through said stencil;

retaining said semiconductor device, said lead frame, and said non-conductive polymer adhesive at room temperature;

positioning said attaching surface of said lead frame and said active surface of said semiconductor device relative to each other; and

urging said active surface of said semiconductor device and said attaching surface of said lead frame together to attach said semiconductor device and said lead frame together, thereby effecting electrical connection between said attaching surface of said lead frame and said active surface of said semiconductor device.

8. A method of assembling a semiconductor device assembly, said method comprising:

providing a lead frame having an attaching surface;

providing a semiconductor device having a plurality of bond pads located on an active surface thereof configured for electrical connection to said lead frame;

providing a stencil;

forming a selected pattern in said stencil;

selecting a non-conductive polymer adhesive which includes a first material from a group of copolymers that includes isobutyl acetal diphenol copolymer and a second material that is from a group of metal oxides that includes titanium dioxide;

positioning said stencil and one of said attaching surface of said lead frame and said active surface of said semiconductor device relative to each other;

applying said non-conductive polymer adhesive through said stencil to one of said active surface of said semiconductor device and said attaching surface of said lead frame;

retaining said semiconductor device, said lead frame, and said non-conductive polymer adhesive at room temperature;

positioning said attaching surface of said lead frame and said active surface of said semiconductor device relative to each other; and

urging said active surface of said semiconductor device and said attaching surface of said lead frame together at room temperature to attach said semiconductor device and said lead frame together, thereby effecting an electrical connection between said attaching surface of said lead frame and said active surface of said semiconductor device.

9. A method of assembling a semiconductor device assembly said method comprising:

providing a lead frame having an attaching surface;

providing a semiconductor device having at least one bond pad on an active surface thereof configured for electrical connection to said lead frame;

providing a stencil;

forming a selected pattern in said stencil;

selecting an adhesive that includes from about 75 percent to about 95 percent of isobutyl acetal diphenol copolymer and from about 25 percent to about 5 percent, respectively, of titanium dioxide;

positioning said stencil and one of said lead frame and said semiconductor device relative to each other;

applying said adhesive through said stencil to one of said semiconductor device and said lead frame;

retaining said semiconductor device, said lead frame, and said adhesive at room temperature;

positioning said lead frame and said semiconductor device relative to each other; and

urging said semiconductor device and said lead frame together to attach said semiconductor device and said lead frame together, thereby effecting an electrical connection between said attaching surface of said lead frame and said active surface of said semiconductor device.