WikiPatents - Community Patent Review
Create Free Account  |  License or Sell Your Patent  |  WikiPatents Marketplace  |  WikiPatents Blog
Username:  Password:  
    
Advanced Search
Microbump interconnect for semiconductor dice    
United States Patent6127736   
Link to this pagehttp://www.wikipatents.com/6127736.html
Inventor(s)Akram; Salman (Boise, ID)
AbstractA method for forming an interconnect for making a temporary or permanent electrical connection to a semiconductor dice is provided. The interconnect includes a rigid substrate on which an insulating layer and a pattern of conductors are formed. A compliant layer is formed on the insulating layer of a material such as polyimide. Vias are formed in the compliant layer with metal contacts in electrical communication with the conductors. Microbumps are formed on the compliant layer in electrical communication with the contacts and are adapted to flex with the compliant layer. The interconnect can be used to provide a temporary electrical connection for testing bare semiconductor dice. Alternately the interconnect can be used for flip chip mounting dice for fabricating multi chip modules and other electronic devices.
   














 Title Information Submit all comments and votes
 
Patent Text Patent PDF Print Page Summary File History
Plain text PDF images Print Summary File History
Drawing from US Patent 6127736
Microbump interconnect for semiconductor dice - US Patent 6127736 Drawing
Microbump interconnect for semiconductor dice
Inventor     Akram; Salman (Boise, ID)
Owner/Assignee     Micron Technology, Inc. (Boise, ID)
Patent assignment
All assignments
Publication Date     October 3, 2000
Application Number     09/127,652
PAIR File History     Application Data   Transaction History
Image File Wrapper   Patent Term   Fees
Litigation
Filing Date     July 31, 1998
US Classification     257/780 257/48 257/781 257/E23.067
Int'l Classification    
Examiner     Clark; Sheila V.
Assistant Examiner    
Attorney/Law Firm     Gratton; Stephen A.
Address
Parent Case     CROSS REFERENCE TO RELATED APPLICATIONS This application is a division of application Ser. No. 08/617,283, filed on Mar. 18, 1996, U.S. Pat. No. 5,789,271.
Priority Data    
USPTO Field of Search     257/783 257/782 257/780 257/781 257/778 257/48
Patent Tags     microbump interconnect semiconductor dice
   
Enter a comma (,) or semicolon (;) between multiple tag words/phrases.
Describe this patent:
 Amusing   
 Clever   
 Complex   
 Efficient   
 Historic   
 Important   
 Innovative   
 Interesting   
 Practical   
 Simple   
[no votes]
Patent WIKI

Share information and news about this patent, including information and news about the technology, inventors, company, ligation and licensing.

 References Submit all comments and votes
 
*references marked with an asterisk below are user-added references
 U.S. References
 
Add a new US reference:  
ReferenceRelevancyCommentsReferenceRelevancyComments
5872404
Lynch et al.

Feb,1999

[0 after 0 votes]
5869904
Shoji et al.

Feb,1999

[0 after 0 votes]
5834366
Akram

Nov,1998

[0 after 0 votes]
5808360
Akram

Sep,1998

[0 after 0 votes]
5801449
Dehaine et al.

Sep,1998

[0 after 0 votes]
5789271
Akram

Aug,1998

[0 after 0 votes]
5753973
Yasunaga et al.

May,1998

[0 after 0 votes]
5757078
Matsuda et al.

May,1998

[0 after 0 votes]
5678301
Gochnour et al.

Oct,1997

[0 after 0 votes]
5661336
Phelps, Jr. et al.

Aug,1997

[0 after 0 votes]
5656858
Kondo et al.

Aug,1997

[0 after 0 votes]
5602422
Schueller et al.

Feb,1997

[0 after 0 votes]
5569960
Kumazawa et al.

Oct,1996

[0 after 0 votes]
5534465
Frye et al.

Jul,1996

[0 after 0 votes]
5492235
Crafts et al.

Feb,1996

[0 after 0 votes]
5487999
Farnworth

Jan,1996

[0 after 0 votes]
5461261
Nishiguchi

Oct,1995

[0 after 0 votes]
5440240
Wood et al.

Aug,1995

[0 after 0 votes]
5438223
Higashi et al.

Aug,1995

[0 after 0 votes]
5426072
Finnila

Jun,1995

[0 after 0 votes]
5408190
Wood et al.

Apr,1995

[0 after 0 votes]
5376584
Agarwala

Dec,1994

[0 after 0 votes]
5367253
Wood et al.

Nov,1994

[0 after 0 votes]
5329423
Scholz

Jul,1994

[0 after 0 votes]
5308796
Feldman

May,1994

[0 after 0 votes]
5302891
Wood et al.

Apr,1994

[0 after 0 votes]
5289631
Koopman

Mar,1994

[0 after 0 votes]
5262718
Svendsen et al.

Nov,1993

[0 after 0 votes]
5225037
Elder et al.

Jul,1993

[0 after 0 votes]
5169680
Ting et al.

Dec,1992

[0 after 0 votes]
5123850
Elder et al.

Jun,1992

[0 after 0 votes]
5090118
Kwon et al.

Feb,1992

[0 after 0 votes]
5072289
Sugimoto et al.

Dec,1991

[0 after 0 votes]
4970571
Yamakawa et al.

Nov,1990

[0 after 0 votes]
4927505
Sharma et al.

May,1990

[0 after 0 votes]
4764804
Sahara et al.

Aug,1988

[0 after 0 votes]
4661375
Thomas

Apr,1987

[0 after 0 votes]
4005472
Harris et al.

Jan,1977

[0 after 0 votes]
3809625
Brown et al.

May,1974

[0 after 0 votes]
3461357
Mutter et al.

Aug,1969

[0 after 0 votes]
 Foreign References
 Other References
 Market Review Submit all comments and votes
   
Market Size
Estimate the gross annual revenues of the relevant market sector:
> $10B
$5B - $10B
$2B - $5B
$500M - $2B
$100M - $500M
$10M - $100M
$1M - $10M
$500K - $1M
$100K - $500K
< $100K
[No votes]
$0
 
$0   $2.5B   $5B   $7.5B   $10B
Market Share
Estimate the percentage of the relevant market sector this invention will capture:
75% - 100%
50% - 74.99%
25% - 49.99%
10 - 24.99%
5 - 9.99%
2 - 4.99%
1 - 1.99%
< 1%
[No votes]
0.0%
 
0%   25%   50%   75%   100%
Reasonable Royalty
What percentage of gross sales should the inventor or assignee be paid?
75% - 100%
50% - 74.99%
25% - 49.99%
10 - 24.99%
5 - 9.99%
2 - 4.99%
1 - 1.99%
< 1%
[No votes]
0.0%
 
0%   25%   50%   75%   100%
Public's "Guesstimation" of Royalty Value
Market SizeN/A[No votes]
xMarket ShareN/A[No votes]
xReasonable RoyaltyN/A[No votes]

N/A

License Availablity
If you are NOT the owner or assignee, answer here:
Yes, license is available for purchase

No, license is not currently available



[No votes]
License Availablity
If you ARE the owner or assignee, answer here:
Yes, license is available for purchase

No, license is not currently available



[No votes]
Competitive Advantage
Does this invention have a significant competitive advantage over similar technologies?
Yes

No



[No votes]
Most helpful competitive advantage comment
[No comments]

Commercial Alternatives
Are there viable commercial alternatives for this invention?
Yes

No



[No votes]
Most helpful commercial alternative comment
[No comments]

 Technical Review Submit all comments and votes
 Claims Submit all comments and votes
 


What is claimed is:

1. An interconnect configured for use in a test apparatus for testing a semiconductor die having a plurality of contacts in a first pattern comprising:

a substrate comprising an electrically insulating first layer;

a plurality of conductors on the first layer;

an electrically insulating second layer on the conductors comprising a compliant polymeric material;

a plurality of vias through the second layer to the conductors having a second pattern matching the first pattern; and

a plurality of microbumps on the second layer aligned with the vias and in electrical communication with the conductors, the microbumps substantially larger than the vias such that the microbumps are supported by the second layer and can flex with the second layer to make temporary electrical connections with the contacts on the die upon application of a force by the test apparatus.

2. The interconnect of claim 1 wherein the substrate comprises a material selected from the group consisting of silicon, silicon-on-glass, silicon-on-sapphire, germanium, and ceramic.

3. The interconnect of claim 1 wherein the second layer comprises polyimide having a thickness of from about 0.5 .mu.m to 15 .mu.m.

4. The interconnect of claim 1 wherein the second layer comprises a tape applied to the substrate.

5. The interconnect of claim 1 wherein the contacts comprise bond pads and the microbumps have a generally hemispherical shape.

6. The interconnect of claim 1 wherein the microbumps have a diameter of from about 15 .mu.m to 10 .mu.m.

7. The interconnect of claim 1 wherein the vias comprise second contacts bonded to the microbumps.

8. A multi chip module comprising:

a substrate comprising an electrically insulating first layer;

a plurality of conductors on the first layer;

an electrically insulating second layer on the conductors comprising a compliant polymeric material;

a plurality of vias through the second layer to the conductors having a first diameter and a first pattern;

a plurality of microbumps in the vias in electrical communication with the conductors, the microbumps having a second diameter substantially larger than the first diameter such that the microbumps are supported by the second layer and can flex with the second layer upon application of an external force; and

at least one semiconductor die flip chip mounted to the substrate comprising a plurality of contacts in a second pattern matching the first pattern and bonded to the microbumps.

9. The multi chip module of claim 8 wherein the substrate comprises a material selected from the group consisting of silicon, silicon-on-glass, silicon-on-sapphire, germanium, and ceramic.

10. The multi chip module of claim 8 wherein the second layer comprises polyimide having a thickness of from about 0.5 .mu.m to 15 .mu.m.

11. The multi chip module of claim 8 wherein the contacts comprise bond pads and the microbumps have a Generally hemispherical shape.

12. The multi chip module of claim 8 wherein the microbumps comprise solder and the vias comprise solder wettable contacts.

13. The multi chip module of claim 8 wherein the second layer comprises a tape applied to the substrate.

14. An interconnect configured for use in a test apparatus for testing a semiconductor die having a plurality of contacts in a first pattern comprising:

a substrate;

a plurality of conductors on the substrate;

an electrically insulating layer on the conductors comprising a compliant polymeric material;

a plurality of vias through the layer to the conductors having a second pattern matching the first pattern; and

a plurality of microbumps supported by the layer and aligned with the vias in electrical communication with the conductors, the microbumps configured to make temporary electrical connections with the contacts on the die, and to flex with the layer during application of an external force by the test apparatus to accommodate dimensional variations in the contacts or the microbumps.

15. The interconnect of claim 14 wherein the compliant polymeric material comprises a layer of tape.

16. The interconnect of claim 14 wherein the contacts on the die comprise bond pads and the microbumps have a generally hemispherical shape.

17. The interconnect of claim 14 wherein the microbumps have a diameter of from about 15 .mu.m to 100 .mu.m.

18. The interconnect of claim 14 wherein the polymeric material has a thickness of from about 0.5 .mu.m to 15 .mu.m.

19. An interconnect configured for use in a test apparatus for testing a semiconductor die having a plurality of contacts in a first pattern comprising:

a substrate;

a plurality of conductors on the substrate;

an electrically insulating compliant layer on the conductors comprising a polymeric material;

a plurality of vias through the compliant layer to the conductors, the vias having a first diameter and a second pattern matching the first pattern; and

a plurality of microbumps on the compliant layer configured to make temporary electrical connections with the contacts on the die, the microbumps aligned with the vias in electrical communication with the conductors, the microbumps having a second diameter substantially larger than the first diameter such that the microbumps can flex with the compliant layer during application of an external force by the test apparatus to accommodate dimensional variations in the contacts or the microbumps during making of the temporary electrical connections.

20. The interconnect of claim 19 wherein the compliant layer comprises polyimide.

21. The interconnect of claim 19 wherein the compliant layer comprises polyimide tape.

22. A multi chip module comprising:

a substrate;

at least one semiconductor die flip chip mounted to the substrate comprising a plurality of contacts in a first pattern;

a plurality of conductors on the substrate;

an electrically insulating compliant layer on the conductors comprising a polymeric material;

a plurality of vias through the compliant layer to the conductors having a second pattern matching the first pattern;

a plurality of microbumps supported by the compliant layer and aligned with the vias in electrical communication with the conductors, the microbumps bonded to the contacts on the die, and configured to flex with the compliant layer upon application of an external force to accommodate dimensional variations in the contacts or the microbumps.

23. The multi chip module of claim 22 wherein the vias have a first diameter and the microbumps have a second diameter substantially larger than the first diameter.
 Description Submit all comments and votes
 


FIELD OF THE INVENTION

This invention relates generally to semiconductor manufacture and specifically to a method for fabricating a microbump interconnect for a bare semiconductor die.

BACKGROUND OF THE INVENTION

In the manufacture of unpackaged semiconductor dice it is sometimes necessary to make an electrical connection with the bond pads of the dice for testing or other purposes. For example, burn-in and full functionality tests are used to certify each unpackaged die as a known good die (KGD). During the test procedures test apparatus for a single bare die (also referred to as carriers) take the place of conventional plastic or ceramic semiconductor packages. Exemplary test apparatus are disclosed in U.S. Pat. Nos. 5,302,891; 5,408,190 and 5,495,179 to Wood et al.

This type of test apparatus typically includes an interconnect component for making the temporary electrical connection between the die and test apparatus. For example, U.S. Pat. No. 5,483,741 to Akram et al. discloses a method for fabricating an interconnect with silicon contact members.

Another type of interconnect for these test apparatus is formed with microbump contact members. For example, U.S. Pat. No. 5,487,999 to Farnworth discloses an interconnect for bare dice that includes microbump contact members. Microbump interconnects can be fabricated using TAB tape developed for tape automated bonding of semiconductor dice. This type of TAB tape is sold by Nitto Denko America, Inc. under the trademark ASMATTM.

The microbump contact members comprise metal bumps formed on an insulative polyimide film. The microbumps can be formed on metal filled vias using an electroplating process. In addition, conductive traces formed of patterned metal foil are also mounted to the polyimide film to establish a circuit path to the microbumps. For forming an interconnect for testing bare dice, the polyimide film with the microbumps and conductive traces thereon, can be mounted to a rigid substrate.

With this type of microbump interconnect, the manufacturing process for the microbumps is complicated and requires specialized manufacturing equipment. Following the microbump manufacturing process, the polyimide film must be cut to shape and mounted on the substrate. This can also be a complicated and tedious process. In particular, the polyimide film is fragile and difficult to cut and attach to the rigid substrate. In addition, an adhesive layer must be formed between the polyimide film and the rigid substrate. The thickness and compressive properties of this adhesive layer can have a profound effect on the function of the microbump interconnect. Accordingly, undesirable variables can be introduced by the steps and materials used during the substrate mounting process.

The present invention is directed to a simplified method for forming microbump interconnects directly on a rigid substrate. This eliminates a separate substrate mounting step for the microbumps. In addition, fabrication of the microbumps is simplified and an improved low resistance microbump structure is provided.

In view of the foregoing, it is an object of the present invention to provide an improved method for forming a microbump interconnect for bare semiconductor dice.

It is a further object of the invention to provide an improved method for forming a microbump interconnect having a rigid substrate and low resistance microbumps formed on a flexible compliant