Microelectric packages having deformed bonded leads and methods therefor

• US 6,848,173 B2
• Filed: 01/22/2001
• Issued: 02/01/2005
• Est. Priority Date: 07/07/1994
• Status: Expired due to Fees

• Current Assignee: Tessera, Inc. (Adeia Inc.)
• Original Assignee: Tessera, Inc. (Adeia Inc.)
• Inventors: Beroz, Masud, Haba, Belgacem, Fjelstad, Joseph, Smith, John W.
• Primary Examiner(s): TUGBANG, ANTHONY D
• Application Number:
  US09/766,814
• Publication Number:
  US 20020068426A1
• Time in Patent Office: 1,471 Days
• Field of Search: 298/30, 298/32, 298/40, 29842-843, 29854-855, 298/57, 298/61, 298/41, 298/60, 438107-109, 257777-778, 257/783, 228/180.21, 228/180.5, 228/215, 156/307.3, 156/313, 156/275.5
• US Class Current: 29/840
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/05553 being rectangular
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/131 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/29 of an individual layer connector
• CPC Class Codes: H01L 2224/29099 Material
• CPC Class Codes: H01L 2224/29101 the principal constituent melting at a temperature of less than 400°C
• CPC Class Codes: H01L 2224/2919 with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/29199 Material of the matrix
• CPC Class Codes: H01L 2224/2929 with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/29299 Base material
• CPC Class Codes: H01L 2224/293 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/32145 the bodies being stacked
• 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 2224/4824 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 2224/49431 : on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73203 : Bump and layer connectors
• CPC Class Codes: H01L 2224/73204 : the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 2224/73257 : Bump and wire connectors
• CPC Class Codes: H01L 2224/73265 : Layer and wire connectors
• CPC Class Codes: H01L 2224/78 : Apparatus for connecting with wire connectors
• CPC Class Codes: H01L 2224/83138 : the guiding structures being at least partially left in the finished device
• CPC Class Codes: H01L 2224/8319 : Arrangement of the layer connectors prior to mounting
• CPC Class Codes: H01L 2224/838 : Bonding techniques
• CPC Class Codes: H01L 2224/8393 : Reshaping
• CPC Class Codes: H01L 2224/85186 : connecting first outside the semiconductor or solid-state body, i.e. off-chip, reverse stitch
• CPC Class Codes: H01L 2224/85205 : Ultrasonic bonding
• CPC Class Codes: H01L 2224/85207 : Thermosonic bonding
• CPC Class Codes: H01L 2224/85399 : Material
• CPC Class Codes: H01L 2224/8593 : Reshaping, e.g. for severing the wire, modifying the wedge or ball or the loop shape
• CPC Class Codes: H01L 2224/92247 : the second connecting process involving a wire connector
• CPC Class Codes: H01L 2225/0651 : Wire or wire-like electrical connections from device to substrate
• CPC Class Codes: H01L 2225/06558 : the devices having passive surfaces facing each other, i.e. in a back-to-back arrangement
• CPC Class Codes: H01L 23/49811 : Additional leads joined to the metallisation on the insulating substrate, e.g. pins, bumps, wires, flat leads H01L23/49827 takes precedence
• CPC Class Codes: H01L 24/16 : of an individual bump connector
• 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 24/49 : of a plurality of wire connectors
• CPC Class Codes: H01L 24/50 : Tape automated bonding [TAB] connectors, i.e. film carriers; Manufacturing methods related thereto thin flexible metallic tape with or without a film carrier H01L23/49572, flexible insulating substrates H01L23/4985, H01L23/5387
• CPC Class Codes: H01L 24/73 : Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 24/78 : Apparatus for connecting with wire connectors
• CPC Class Codes: H01L 24/83 : using a layer connector
• CPC Class Codes: H01L 24/85 : using a wire connector wire bonding in general B23K20/004
• CPC Class Codes: H01L 24/86 : using tape automated bonding [TAB]
• CPC Class Codes: H01L 25/0657 : Stacked arrangements of devices
• 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 2924/00013 : Fully indexed content
• 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 2924/01023 : Vanadium [V]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/0665 : Epoxy resin
• CPC Class Codes: H01L 2924/10161 : with a rectangular active surface
• CPC Class Codes: H01L 2924/15311 : being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/1815 : Shape
• CPC Class Codes: Y10T 29/4913 : Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49144 : by metal fusion
• CPC Class Codes: Y10T 29/49149 : by metal fusion bonding
• CPC Class Codes: Y10T 29/49169 : Assembling electrical component directly to terminal or elongated conductor
• CPC Class Codes: Y10T 29/49179 : by metal fusion bonding

Abstract

A method of making a microelectronic assembly includes juxtaposing a first element, such as a dielectric sheet having conductive leads thereon with a second element, such as a semiconductor chip, having contact thereon, and wire bonding the conductive leads on the first element to the contacts on the second element so that elongated bonding wires extend between the conductive leads and the contacts. After the wire bonding step, the first and second elements are moved through a pre-selected displacement relative to one another so as to deform the bonding wires. A flowable dielectric material may be introduced between the first and second elements and around the bonding wires during or after the moving step. The flowable material may be cured to form an encapsulant around at least a portion of the bonding wires.

Claims

1. A method of making a microelectronic assembly comprising:

(a) providing a connection component having a first surface including conductive leads and contacts, said conductive leads having terminal ends permanently secured to said connection component and tip ends releasably secured to said connection component;

(b) juxtaposing a first microelectronic element having contacts with the first surface of said connection component and attaching the contacts of said first microelectronic element to the tip ends of said leads;

(c) attaching a second microelectronic element having contacts to a back surface of said first microelectronic element, wherein the contacts of said second microelectronic element face away from the first surface of said connection component;

(d) wire bonding the contacts on said connection component with the contacts of said second microelectronic element so that elongated bonding wires extend between the contacts of said connection component and the contacts of said second microelectronic element; and

(e) after the wire bonding step, moving said first and second microelectronic elements through a preselected displacement relative to said connection component so as to deform the bonding wires and the leads.

2. The method as claimed in claim 1, wherein the moving step further comprises:

releasing the tip ends of said leads from the top surface of said connection component; and

bending said leads into a substantially s-shaped configuration.

3. The method as claimed in claim 1, wherein said bonding wires flex and bend during the moving step for maintaining an electrical connection between the contacts of said second microelectronic element and the contacts of said connection component.

4. The method as claimed in claim 1, further comprising introducing a curable liquid material between a top surface of said connection component and a contact bearing face of said first microelectronic element.

5. The method as claimed in claim 4, wherein said curable liquid material is introduced during the moving step so that said first and second microelectronic elements move away from said connection component at least partially under the influence of pressure of said curable liquid material.

6. The method as claimed in claim 4, wherein the introducing the curable liquid material step includes encapsulating said first and second microelectronic elements, the contacts of said second microelectronic element, and said conductive wires with said curable liquid material.

7. The method as claimed in claim 4, further comprising curing said curable liquid material so as to provide a compliant layer that enables said first and second microelectronic elements to move relative to said connection component during thermal cycling of said microelectronic assembly.

8. The method as claimed in claim 7, wherein said compliant layer enables said conductive wires and conductive leads to flex and bend during thermal cycling for maintaining reliable electrical interconnections within said microelectronic assembly.

9. The method as claimed in claim 1, wherein said connection component comprises a flexible dielectric sheet having the first surface and a second surface remote therefrom.

10. The method as claimed in claim 9, wherein said connection component includes one or more terminals accessible at the second surface thereof, said terminals being electrically interconnected with the permanently secured ends of said leads or to the contacts of said connection component.

11. The method as claimed in claim 10, further comprising attaching one or more conductive masses to the terminals of said connection component.

12. The method as claimed in claim 11, further comprising bonding said microelectronic assembly to a printed circuit board.

13. The method as claimed in claim 1, wherein said first microelectronic element includes one or more semiconductor chips.

14. The method as claimed in claim 1, wherein said second microelectronic element includes one or more semiconductor chips.

15. The method as claimed in claim 1, wherein said conductive wires have first ends bonded to one of the contacts of said second microelectronic element and second ends bonded to the contacts of said connection component.

16. The method as claimed in claim 1, wherein said first microelectronic element or said second microelectronic element includes a semiconductor wafer.

17. The method as claimed in claim 1, further comprising attaching rear surfaces of said first and second microelectronic elements to one another.

18. The method as claimed in claim 17, wherein the attaching step includes providing an adhesive between the rear surfaces of said first and second microelectronic elements.

19. The method as claimed in claim 17, wherein said adhesive is a thermally conductive adhesive.

20. The method as claimed in claim 1, further comprising electrically interconnecting one or more of said leads of said connection component with one or more of said contacts of said connection component.

21. A method of making a microelectronic assembly comprising:

(a) providing a connection component having a first surface including conductive leads and contacts, said conductive leads having terminal ends permanently secured to said connection component and tip ends releasably secured to said connection component;

(b) juxtaposing a first microelectronic element having contacts with the first surface of said connection component and attaching the contacts of said first microelectronic element to the tip ends of said leads;

c) attaching a second microelectronic element having contacts to a back surface of said first microelectronic element, wherein the contacts of said second microelectronic element face away from the first surface of said connection component;

d) wire bonding the contacts on said connection component with the contacts of said second microelectronic element so that elongated bonding wires extend between the contacts of said connection component and the contacts of said second microelectronic element;

e) after the wire bonding step, moving said first and second microelectronic elements through a preselected displacement relative to said connection component so as to deform the bonding wires and the leads; and

f) introducing a curable liquid material between at top surface of said connection component and a contact bearing face of said first microelectronic element, wherein said curable liquid material is introduced during or after the moving step.

22. A method of making a microelectronic assembly comprising:

(a) providing a connection component having a first surface including conductive leads and contacts, said conductive leads having terminal ends permanently secured to said connection component and tip ends releasably secured to said connection component;

(b) juxtaposing a first microelectronic element having contacts with the first surface of said connection component and attaching the contacts of said first microelectronic element to the tip ends of said leads;

c) attaching a second microelectronic element having contacts to a back surface of said first microelectronic element, wherein the contacts of said second microelectronic element face away from the first surface of said connection component;

(d) wire bonding the contacts on said connection component with the contacts of said second microelectronic element so that elongated bonding wires extend between the contacts of said connection component and the contacts of said second microelectronic element;

e) after the wire bonding step, moving said first and second microelectronic elements through a preselected displacement relative to said connection component so as to deform the bonding wires and the leads; and

(f) providing an expandable structure between said first microelectronic element and said connection component and expanding said expandable structure during the moving step.