US5756370A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compliant contact system with alignment structure for testing unpackaged semiconductor dice
Assignee: Micron Technology Inc
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Filing: 1996-02-08
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Granted: 1998-05-26
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Expires: 2016-02-08
Abstract
Abstract A compliant contact system for making a temporary electrical connection with a semiconductor die for testing and a method for fabricating the compliant contact system are provided. The compliant contact system is adapted for use with a test apparatus for known good die. The compliant contact system includes an interconnect, and can include an alignment fixture for aligning the die with the interconnect. The interconnect includes a pattern of compliant contacts adapted to contact the bond pads on the die. The compliant contacts are formed as metal traces on a silicon substrate. The end portions of the metal traces are cantilevered over a pit etched into the substrate, and are adapted to flex to compensate for dimensional variations in the bond pads and to provide a bias force against the bond pads.
Inventors
- 👤 Warren M. Farnworth
- 👤 Salman Akram
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:01
CPC Classifications
G; G01; G01R; G01R1/00; G01R1/02; G01R1/06; G01R1/067; G01R1/073; G01R1/07307; G01R1/07342; G01R1/06711; G01R1/06733; G01R1/06738; G01R1/06755; G01R3/00
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
114 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming a first layer on the substrate; forming a metal trace on the first layer, the metal trace having a thickness "t", a width "w" and a modulus of elasticity "E"; etching the first layer to undercut a portion of the first layer supporting an end portion of the metal trace and form a pit proximate to the end portion, with the end portion having a length "l" cantilevered over the pit and adapted to flex upon contact with the contact location; and selecting "t", "w", "E" and "l" to form the end portion with a desired spring constant "C".
Claim 2
Independent Claim
114 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming a first layer on the substrate; forming a metal trace on the first layer, the metal trace having a thickness "t", a width "w" and a modulus of elasticity "E"; etching the first layer to undercut a portion of the first layer supporting an end portion of the metal trace and form a pit proximate to the end portion, with the end portion having a length "l" cantilevered over the pit and adapted to flex upon contact with the contact location; and selecting "t", "w", "E" and "l" to form the end portion with a desired spring constant "C".
Claim 3
Dependent Claim
17 words
The method as claimed in claim 1 further comprising forming a metal bump on the end portion.
Claim 4
Dependent Claim
25 words
The method as claimed in claim 2 wherein forming the metal bump comprises a process selected from the group consisting of metallization, plating and evaporation.
Claim 5
Dependent Claim
24 words
The method as claimed in claim 1 wherein the substrate comprises a wafer and the wafer is singulated to form a plurality of interconnects.
Claim 6
Dependent Claim
28 words
The method as claimed in claim 1 further comprising providing an alignment fixture with an alignment opening for the die and attaching the alignment fixture to the substrate.
Claim 7
Dependent Claim
27 words
The method as claimed in claim 1 wherein the metal trace comprises a metal selected from the group consisting of tungsten, titanium, nickel, platinum, iridium and vanadium.
Claim 8
Dependent Claim
31 words
The method as claimed in claim 1 wherein the metal trace includes a bump comprising a metal selected from the group consisting of tungsten, titanium, nickel, platinum, iridium, gold and copper.
Claim 9
Dependent Claim
27 words
The method as claimed in claim 7 further comprising forming the bump with a rough textured surface having asperities for penetrating the contact location on the die.
Claim 10
Independent Claim
134 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate wafer; forming a first layer on the substrate wafer; forming a plurality of metal traces on the first layer, each metal trace having a thickness "t", a width "w" and a modulus of elasticity "E"; etching the first layer to undercut portions of the first layer supporting end portions of the metal traces and form a pit proximate to the end portions, with the end portions of each metal trace having a length "l" cantilevered over the pit and adapted to flex upon contact with a contact location on the die; singulating the substrate wafer to define a periphery of the interconnect; and selecting "t", "w", "E" and "l" to form the end portions with a desired spring constant "C".
Claim 11
Independent Claim
134 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate wafer; forming a first layer on the substrate wafer; forming a plurality of metal traces on the first layer, each metal trace having a thickness "t", a width "w" and a modulus of elasticity "E"; etching the first layer to undercut portions of the first layer supporting end portions of the metal traces and form a pit proximate to the end portions, with the end portions of each metal trace having a length "l" cantilevered over the pit and adapted to flex upon contact with a contact location on the die; singulating the substrate wafer to define a periphery of the interconnect; and selecting "t", "w", "E" and "l" to form the end portions with a desired spring constant "C".
Claim 12
Dependent Claim
33 words
The method as claimed in claim 9 further comprising providing an alignment wafer having a plurality of alignment openings and attaching the alignment wafer to the substrate wafer prior to the singulating step.
Claim 13
Dependent Claim
16 words
The method as claimed in claim 9 further comprising forming metal bumps on the end portions.
Claim 14
Dependent Claim
18 words
The method as claimed in claim 11 further comprising forming a rough textured surface on the metal bumps.
Claim 15
Dependent Claim
21 words
The method as claimed in claim 9 wherein the substrate comprises silicon and the first layer comprises an electrically insulating material.
Claim 16
Dependent Claim
26 words
The method as claimed in claim 9 wherein the substrate wafer comprises a material selected from the group consisting of silicon, silicon-on-glass, silicon-on-sapphire, germanium, or ceramic.
Claim 17
Dependent Claim
26 words
The method as claimed in claim 9 wherein the metal traces comprise a material selected from the group consisting of tungsten, titanium, nickel, platinum and iridium.
Claim 18
Independent Claim
115 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming a first layer on the substrate; forming a metal trace on the first layer, the metal trace having a thickness "t", a width "w" and a modulus of elasticity "E", the metal trace having a contact portion configured to electrically engage a contact location on the die; etching the first layer to an endpoint of the substrate to undercut a portion of the first layer supporting the contact portion, and to cantilever the contact portion over the substrate by a length "l"; and selecting "t", "w", "E" and "l" to form the contact portion with a desired spring constant "C".
Claim 19
Independent Claim
115 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming a first layer on the substrate; forming a metal trace on the first layer, the metal trace having a thickness "t", a width "w" and a modulus of elasticity "E", the metal trace having a contact portion configured to electrically engage a contact location on the die; etching the first layer to an endpoint of the substrate to undercut a portion of the first layer supporting the contact portion, and to cantilever the contact portion over the substrate by a length "l"; and selecting "t", "w", "E" and "l" to form the contact portion with a desired spring constant "C".
Claim 20
Dependent Claim
25 words
The method as claimed in claim 16 further comprising following the etching step, forming a second layer on the substrate proximate to the contact portion.
Claim 21
Dependent Claim
33 words
The method as claimed in claim 16 further comprising following the etching step, etching the substrate proximate to the end portion to form a pit in the substrate proximate to the contact portion.
Claim 22
Dependent Claim
18 words
The method as claimed in claim 16 further comprising forming a rough textured surface on the contact portion.
Claim 23
Dependent Claim
17 words
The method as claimed in claim 16 further comprising forming a metal bump on the contact portion.
Claim 24
Independent Claim
105 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming a first layer on the substrate; forming a metal trace on the first layer, the metal trace having a thickness "t", a width "w" and a modulus of elasticity "E", the metal trace having a contact portion configured to electrically engage a contact location on the die; etching the first layer to form a pit proximate to the contact portion, with the contact portion having a length "l" cantilevered over the pit; and selecting "t", "w", "E" and "l" to form the contact portion with a desired spring constant "C".
Claim 25
Independent Claim
105 words
A method for fabricating an interconnect for a semiconductor die comprising: providing a substrate; forming a first layer on the substrate; forming a metal trace on the first layer, the metal trace having a thickness "t", a width "w" and a modulus of elasticity "E", the metal trace having a contact portion configured to electrically engage a contact location on the die; etching the first layer to form a pit proximate to the contact portion, with the contact portion having a length "l" cantilevered over the pit; and selecting "t", "w", "E" and "l" to form the contact portion with a desired spring constant "C".
Claim 26
Dependent Claim
16 words
The method as claimed in claim 21 further comprising etching the substrate to form the pit.
Claim 27
Dependent Claim
38 words
The method as claimed in claim 21 further comprising forming the first layer with a second thickness and endpointing the etching step on the substrate such that the pit has a depth approximately equal to the second thickness.
Claim 28
Dependent Claim
21 words
The method as claimed in claim 21 further comprising following the etching step forming an electrically insulating layer on the pit.
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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) | 2001-05-25 | 2001-11-24 | 2002-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-25 | 2005-11-24 | 2006-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-05-25 | 2009-11-24 | 2010-05-26 | $7700.00 | Window Closed / Lapsed |