US5834366A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for fabricating microbump interconnect for bare semiconductor dice
Assignee: Micron Technology Inc
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Filing: 1997-08-19
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Granted: 1998-11-10
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Expires: 2017-08-19
Abstract
Abstract A method for forming an interconnect for making a temporary or permanent electrical connection to a semiconductor dice is provided. The method includes forming a substrate with an insulating layer and a pattern of conductors thereon. The conductors are formed as a bi-metal stack including a barrier layer formed of an inert metal and a conductive layer formed of a highly conductive metal. Microbumps are formed on the conductors by deposition through a mask using an electroplating, electroless plating, screen printing or evaporation process. 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.
Inventors
- 👤 Salman Akram
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:03
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/40; H05K3/4007; H10; H10W; H10W70/00; H10W70/099; H10W72/00; H10W72/01; H10W72/012; H10W72/019; H10W72/20; H10W78/00; H10W90/00; H10W90/701; H05K1/00; H05K1/02; H05K1/0271; H05K2201/00; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0347; H05K2201/0364; H05K2201/0367; H05K2201/10; H05K2201/10613; H05K2201/10742; H05K2201/1075; H05K2201/10848; H05K3/30; H05K3/32; H05K3/325; H05K3/326; H10W72/251; H10W72/252; H10W72/261; H10W72/29; H10W72/851; H10W72/874; H10W72/90; H10W72/941; H10W72/9415; H10W72/951
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
98 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming an electrically insulating polymer layer on the substrate; forming a plurality of conductors on the polymer layer; forming a mask on the substrate comprising a plurality of openings to the conductors corresponding to a pattern of contacts on a die; forming microbumps on the conductors by depositing a metal in the openings, the microbumps configured to electrically engage the contacts on the die and to flex with the polymer layer to accommodate dimensional variations in the microbumps and contacts; and removing the mask.
Claim 2
Independent Claim
98 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming an electrically insulating polymer layer on the substrate; forming a plurality of conductors on the polymer layer; forming a mask on the substrate comprising a plurality of openings to the conductors corresponding to a pattern of contacts on a die; forming microbumps on the conductors by depositing a metal in the openings, the microbumps configured to electrically engage the contacts on the die and to flex with the polymer layer to accommodate dimensional variations in the microbumps and contacts; and removing the mask.
Claim 3
Dependent Claim
16 words
The method of claim 1 wherein the substrate comprises silicon and the polymer layer comprises polyimide.
Claim 4
Dependent Claim
17 words
The method of claim 1 wherein the microbumps are configured to flex to accommodate z-direction dimensional variations.
Claim 5
Independent Claim
99 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming an electrically insulating polymer layer on the substrate; forming a plurality of conductors on the polymer layer; forming a mask on the substrate comprising a plurality of openings to the conductors corresponding to a pattern of contacts on the die; forming microbumps on the conductors by depositing a metal in the openings, the microbumps configured to electrically enrage the contacts on the die and to flex with the compliant layer to accommodate z-direction dimensional variations in the microbumps and contacts; and removing the mask.
Claim 6
Independent Claim
99 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming an electrically insulating polymer layer on the substrate; forming a plurality of conductors on the polymer layer; forming a mask on the substrate comprising a plurality of openings to the conductors corresponding to a pattern of contacts on the die; forming microbumps on the conductors by depositing a metal in the openings, the microbumps configured to electrically enrage the contacts on the die and to flex with the compliant layer to accommodate z-direction dimensional variations in the microbumps and contacts; and removing the mask.
Claim 7
Dependent Claim
13 words
The method of claim 4 further comprising bonding the microbumps to the contacts.
Claim 8
Dependent Claim
19 words
The method of claim 4 further comprising placing the substrate in a test fixture configured to test the die.
Claim 9
Independent Claim
109 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming an electrically insulating polymer layer on the substrate; forming a plurality of conductors on the polymer layer; forming a mask on the substrate comprising a plurality of openings on the conductors corresponding to a pattern of contacts on the die; depositing a metal in the openings to form a plurality of microbumps configured to electrically engage the contacts on the die and to flex with the polymer layer to accommodate z-direction dimensional variations in the microbumps and contacts; removing the mask; and placing the substrate in a test fixture configured to test the die.
Claim 10
Independent Claim
109 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming an electrically insulating polymer layer on the substrate; forming a plurality of conductors on the polymer layer; forming a mask on the substrate comprising a plurality of openings on the conductors corresponding to a pattern of contacts on the die; depositing a metal in the openings to form a plurality of microbumps configured to electrically engage the contacts on the die and to flex with the polymer layer to accommodate z-direction dimensional variations in the microbumps and contacts; removing the mask; and placing the substrate in a test fixture configured to test the die.
Claim 11
Dependent Claim
10 words
The method of claim 7 wherein the substrate comprises silicon.
Claim 12
Dependent Claim
16 words
The method of claim 7 wherein the substrate comprises silicon and the polymer layer comprises polyimide.
Claim 13
Independent Claim
103 words
A method for fabricating a multi chip module comprising: providing a die comprising a plurality of contacts; providing a substrate; forming an electrically insulating polymer layer on the substrate; forming a plurality of conductors on the polymer layer; forming a mask on the substrate comprising a plurality of openings to the conductors; forming microbumps on the conductors by depositing a metal in the openings; removing the mask; placing the die on the substrate with the microbumps electrically contacting the contacts and flexing with the compliant layer to accommodate z-direction dimensional variations in the microbumps and contacts; and bonding the microbumps to the contacts.
Claim 14
Independent Claim
103 words
A method for fabricating a multi chip module comprising: providing a die comprising a plurality of contacts; providing a substrate; forming an electrically insulating polymer layer on the substrate; forming a plurality of conductors on the polymer layer; forming a mask on the substrate comprising a plurality of openings to the conductors; forming microbumps on the conductors by depositing a metal in the openings; removing the mask; placing the die on the substrate with the microbumps electrically contacting the contacts and flexing with the compliant layer to accommodate z-direction dimensional variations in the microbumps and contacts; and bonding the microbumps to the contacts.
Claim 15
Dependent Claim
10 words
The method of claim 10 wherein the metal comprises solder.
Claim 16
Dependent Claim
13 words
The method of claim 10 bonding the microbumps comprises flip chip optical alignment.
Claim 17
Independent Claim
121 words
A method for fabricating a test assembly for a semiconductor die comprising: providing a substrate; forming an electrically insulating polymer layer on the substrate; forming a plurality of conductors on the polymer layer; forming a mask on the substrate comprising a plurality of openings to the conductors corresponding to a pattern of contacts on the die; forming microbumps on the conductors by depositing a metal in the openings, each microbump configured to electrically contact a contact on the die and to flex with the polymer layer to accommodate z-direction dimensional variations; removing the masks; providing a test fixture configured to test the die; and placing the substrate in the test fixture with the conductors in electrical communication with the test fixture.
Claim 18
Independent Claim
121 words
A method for fabricating a test assembly for a semiconductor die comprising: providing a substrate; forming an electrically insulating polymer layer on the substrate; forming a plurality of conductors on the polymer layer; forming a mask on the substrate comprising a plurality of openings to the conductors corresponding to a pattern of contacts on the die; forming microbumps on the conductors by depositing a metal in the openings, each microbump configured to electrically contact a contact on the die and to flex with the polymer layer to accommodate z-direction dimensional variations; removing the masks; providing a test fixture configured to test the die; and placing the substrate in the test fixture with the conductors in electrical communication with the test fixture.
Claim 19
Dependent Claim
18 words
The method as claimed in claim 13 wherein the substrate comprises silicon and the polymer layer comprises polyimide.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-11-09 | 2002-05-11 | 2002-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-11-09 | 2006-05-11 | 2006-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-11-09 | 2010-05-11 | 2010-11-10 | $7700.00 | Window Closed / Lapsed |