US5173451A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Soft bond for semiconductor dies
Assignee: Round Rock Research LLC
•
Filing: 1992-05-26
•
Granted: 1992-12-22
•
Expires: 2012-05-26
Abstract
Abstract On a semiconductor integrated circuit die, a semipermanent electrical connection is effected by the use of wirebond techniques, in which the parameters of the wirebond are controlled, so that less bonding force retains the leadwires to the bondpads than the attachment strength of the bondpads to the die. The wirebond techniques include attaching leadwires to bondpads on the die, using ultrasonic wedge bonding. The strength of the bond between the leadwires is significantly less than the attachment strength of the bondpads, preferably by a ratio which ensures that the bondpads are not lifted from the die when the leadwires are removed by breaking the bond between the leadwires and the bondpads. Subsequent to testing and burnin, the bond between the leadwires and the bondpads is severed. The die are then removed from the die cavity plate and the bondpads may then be attached by conventional means. The technique is useful in providing known good die.
Inventors
- 👤 Larry D. Kinsman
- 👤 Derek J. Gochnour
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:35
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/40; H05K3/4007; G; G01; G01R; G01R1/00; G01R1/02; G01R1/04; G01R1/0408; G01R1/0433; G01R1/0441; G01R1/0466; G01R1/0483; G01R31/00; G01R31/28; G01R31/2851; G01R31/2893; H10; H10P; H10P72/00; H10P72/70; H10P72/74; H10P74/00; H10P74/23; H10W; H10W70/00; H10W70/60; H10W70/62; H10W70/65; H10W70/67; H10W70/68; H10W90/00; H10W90/701; G01R1/06; G01R1/067; G01R1/073; G01R1/07307; G01R1/0735; G01R3/00; G01R31/2855; G01R31/286; G01R31/2863; H05K2201/00; H05K2201/01; H05K2201/0104; H05K2201/0133; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0347; H05K2201/0364; H05K2201/0367; H05K2201/0388; H05K2201/0394; H05K2201/09; H05K2201/09209; H05K2201/09372; H05K2201/09481; H05K2201/095; H05K2201/09563; H05K2203/00; H05K2203/03; H05K2203/0307; H05K2203/07; H05K2203/0703; H05K2203/0723; H05K3/0058; H05K3/0067; H05K3/42; H05K3/423; H10W70/654; H10W70/655; H10W70/681; H10W70/682; H10W72/00; H10W72/071; H10W72/0711; H10W72/07141; H10W72/075; H10W72/07502; H10W72/07504; H10W72/07531; H10W72/07532; H10W72/07533; H10W72/07535; H10W72/50; H10W72/531; H10W72/5363; H10W72/541; H10W72/5449; H10W72/551; H10W72/552; H10W72/5524; H10W72/851; H10W72/874; H10W72/884; H10W72/90; H10W72/931; H10W72/932; H10W90/20; H10W90/24; H10W90/721; H10W90/722; H10W90/731; H10W90/734; H10W90/751; H10W90/754; H10W90/756
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
283 words
Method for connecting a semiconductor circuit die external equipment for testing purposes and testing the die, whereby the die may be subsequently disconnected, characterized by: a) placing the die in a die carrier having a die receiving portion thereon, said die carrier having a plurality of connectors thereon for connection to test circuitry, and said die carrier having a plurality of bondpads in close proximity of the die receiving portion; b) attaching leadwires to the die at bondpads on the die and attaching the leadwires to the bondpads on the die carrier, said attachment of leadwires to the bondpads on the die being with sufficient bonding force to provide an electrical connection and to retain the leadwires on the bondpads on the die during a test sequence, and said bonding force being less than an attachment force of the bondpads on the die to the die and less than the tensile strength of the leadwires separate from the bondpads; c) providing signals to at least one of the bondpads on the die carrier in response to signals to at least one of the connectors, and providing signals to at least one of the connectors in response to signals at least one of the bondpads; d) removing the leadwires from the bondpads on the die by mechanically applying force to the wires, the force applied to the wires resulting in the attachment of the leadwires to the bondpads on the die, wherein, for a given force applied to the leadwires, the bond attachment of the leadwires to the bondpads on the die is removed while the leadwires may remain unsevered and the bondpads remain intact; and e) removing the die from the die carrier.
Claim 2
Dependent Claim
283 words
Method for connecting a semiconductor circuit die external equipment for testing purposes and testing the die, whereby the die may be subsequently disconnected, characterized by: a) placing the die in a die carrier having a die receiving portion thereon, said die carrier having a plurality of connectors thereon for connection to test circuitry, and said die carrier having a plurality of bondpads in close proximity of the die receiving portion; b) attaching leadwires to the die at bondpads on the die and attaching the leadwires to the bondpads on the die carrier, said attachment of leadwires to the bondpads on the die being with sufficient bonding force to provide an electrical connection and to retain the leadwires on the bondpads on the die during a test sequence, and said bonding force being less than an attachment force of the bondpads on the die to the die and less than the tensile strength of the leadwires separate from the bondpads; c) providing signals to at least one of the bondpads on the die carrier in response to signals to at least one of the connectors, and providing signals to at least one of the connectors in response to signals at least one of the bondpads; d) removing the leadwires from the bondpads on the die by mechanically applying force to the wires, the force applied to the wires resulting in the attachment of the leadwires to the bondpads on the die, wherein, for a given force applied to the leadwires, the bond attachment of the leadwires to the bondpads on the die is removed while the leadwires may remain unsevered and the bondpads remain intact; and e) removing the die from the die carrier.
Claim 3
Dependent Claim
30 words
Method as described in claim 1, further comprising: the step of placing the die in a die carrier including securing the die in the die carrier with a thermoplastic adhesive.
Claim 4
Dependent Claim
33 words
Method as described in claim 2, further comprising: the step of removing the die from the die carrier including application of thermal energy to the adhesive, thereby loosening the die from the adhesive.
Claim 5
Dependent Claim
51 words
Method as described in claim 1, further comprising: the step of placing the die in a die carrier including securing the die in the die carrier with a material having a property of exhibiting a static charge sufficient and coefficient of friction sufficient to hold the die in place without adhesive.
Claim 6
Dependent Claim
42 words
Method as described in claim 1, further comprising: the step of placing the die in a die carrier including securing the die in the die carrier with a silicon strip which exhibits a static charge sufficient to hold the die in place.
Claim 7
Dependent Claim
58 words
Method as described in claim 1, further comprising: the step of placing the die in a die carrier including securing the die in the die carrier with a silicon strip which exhibits a static charge sufficient to hold the die in place within the die carrier during the attachment of the leadwires to the bondpads on the die.
Claim 8
Dependent Claim
32 words
Method as described in claim 6, further comprising: placing a lid over the die carrier after the die has been placed in the die carrier, the lid securing the die from movement.
Claim 9
Dependent Claim
27 words
Method as described in claim 1, further comprising: said attachment of the leadwires to the die being accomplished by applying ultrasonic energy applied through an ultrasonic wirebonder.
Claim 10
Dependent Claim
37 words
Method as described in claim 8, further comprising: said attachment of the leadwires to the die being effected with a bond strength which is less than one fourth the attachment strength of the bondpads to the die.
Claim 11
Dependent Claim
36 words
Method as described in claim 8, further comprising: said attachment of the leadwires to the die being effected with a bond strength which is less than half the attachment strength of the bondpads to the die.
Claim 12
Dependent Claim
37 words
Method as described in claim 8, further comprising: said attachment of the leadwires to the die being effected with a bond strength which is less than two thirds the attachment strength of the bondpads to the die.
Claim 13
Dependent Claim
58 words
Method as described in claim 1, further comprising: said attachment of the leadwires to the die being accomplished by applying ultrasonic energy applied through an ultrasonic wirebonder to aluminum leadwire, whereby, the wirebonder is selected to provide a bond size which is less than 0.25 ×the bond size which is appropriate for a permanent wirebond for the die.
Claim 14
Dependent Claim
55 words
Method as described in claim 1, further comprising: said attachment of the leadwires to the die being accomplished by applying ultrasonic energy applied through an ultrasonic wirebonder, whereby, the wirebonder is selected to provide a bond size which is less than 0.1 ×the bond size which is appropriate for a permanent wirebond for the die.
Claim 15
Dependent Claim
255 words
Method for temporarily connecting a semiconductor circuit die to external equipment for testing purposes in order to generate reliability and test data concerning the die, characterized by: a) placing the die in a die carrier having a die receiving portion thereon, said die carrier having a plurality of connectors thereon for connection to test circuitry, and said die carrier having a plurality of bondpads in close proximity of the die receiving portion, the bondpads communicating with the connectors; b) attaching leadwires to the die at bondpads on the die and attaching the leadwires to the bondpads o the die carrier by applying ultrasonic energy applied through an ultrasonic wirebonder, said attachment of leadwires to the bondpads on the die being with sufficient bonding force to provide a electrical connection and to retain the leadwires on the bondpads on the die during a test sequence, and said bonding force being less than an attachment force of the bondpads on the die to the die and less than the tensile strength of the leadwires separate from the bondpads c) removing the leadwires from the bondpads on the die by mechanically applying force to the wires, the force applied to the wires resulting in the attachment of the leadwires to the bondpads on the die, wherein, for a given force applied to the leadwires, the bond attachment of the leadwires to the bondpads on the die is removed while the leadwires may remain unsevered and the bondpads remain intact; and d) removing the die from the die carrier.
Claim 16
Dependent Claim
255 words
Method for temporarily connecting a semiconductor circuit die to external equipment for testing purposes in order to generate reliability and test data concerning the die, characterized by: a) placing the die in a die carrier having a die receiving portion thereon, said die carrier having a plurality of connectors thereon for connection to test circuitry, and said die carrier having a plurality of bondpads in close proximity of the die receiving portion, the bondpads communicating with the connectors; b) attaching leadwires to the die at bondpads on the die and attaching the leadwires to the bondpads o the die carrier by applying ultrasonic energy applied through an ultrasonic wirebonder, said attachment of leadwires to the bondpads on the die being with sufficient bonding force to provide a electrical connection and to retain the leadwires on the bondpads on the die during a test sequence, and said bonding force being less than an attachment force of the bondpads on the die to the die and less than the tensile strength of the leadwires separate from the bondpads c) removing the leadwires from the bondpads on the die by mechanically applying force to the wires, the force applied to the wires resulting in the attachment of the leadwires to the bondpads on the die, wherein, for a given force applied to the leadwires, the bond attachment of the leadwires to the bondpads on the die is removed while the leadwires may remain unsevered and the bondpads remain intact; and d) removing the die from the die carrier.
Claim 17
Dependent Claim
30 words
Method as described in claim 14, further comprising: the step of placing the die in a die carrier including securing the die in the die carrier with a thermoplastic adhesive.
Claim 18
Dependent Claim
33 words
Method as described in claim 15, further comprising: the step of removing the die from the die carrier including application of thermal energy to the adhesive, thereby loosening the die from the adhesive.
Claim 19
Dependent Claim
51 words
Method as described in claim 14, further comprising: the step of placing the die in a die carrier including securing the die in the die carrier with a material having a property of exhibiting a static charge sufficient and coefficient of friction sufficient to hold the die in place without adhesive.
Claim 20
Dependent Claim
42 words
Method as described in claim 14, further comprising: the step of placing the die in a die carrier including securing the die in the die carrier with a silicon strip which exhibits a static charge sufficient to hold the die in place.
Claim 21
Dependent Claim
58 words
Method as described in claim 14, further comprising: the step of placing the die in a die carrier including securing the die in the die carrier with a silicon strip which exhibits a static charge sufficient to hold the die in place within the die carrier during the attachment of the leadwires to the bondpads on the die.
Claim 22
Dependent Claim
32 words
Method as described in claim 19, further comprising: placing a lid over the die carrier after the die has been placed in the die carrier, the lid securing the die from movement.
Claim 23
Dependent Claim
27 words
Method as described in claim 14, further comprising: said attachment o the leadwires to the die being accomplished by applying ultrasonic energy applied through an ultrasonic wirebonder.
Claim 24
Dependent Claim
37 words
Method as described in claim 21, further comprising: said attachment of the leadwires to the die being effected with a bond strength which is less than one fourth the attachment strength of the bondpads to the die.
Claim 25
Dependent Claim
36 words
Method as described in claim 21, further comprising: said attachment of the leadwires to the die being effected with a bond strength which is less than half the attachment strength of the bondpads to the die.
Claim 26
Dependent Claim
37 words
Method as described in claim 21, further comprising: said attachment of the leadwires to the die being effected with a bond strength which is less than two thirds the attachment strength of the bondpads to the die.
Claim 27
Dependent Claim
57 words
Method as described in claim 14, further comprising: said attachment of the leadwires to the die being accomplished by applying ultrasonic energy applied through an ultrasonic wirebonder to aluminum leadwire, whereby, the wirebonder is selected to provide a bond size which is less than 0.25×the bond size which is appropriate for a permanent wirebond for the die.
Claim 28
Dependent Claim
54 words
Method as described in claim 14, further comprising: said attachment of the leadwires to the die being accomplished by applying ultrasonic energy applied through an ultrasonic wirebonder, whereby, the wirebonder is selected to provide a bond size which is less than 0.1×the bond size which is appropriate for a permanent wirebond for the die.
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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) | 1995-12-22 | 1996-06-22 | 1996-12-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-12-22 | 2000-06-22 | 2000-12-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-12-22 | 2004-06-22 | 2004-12-22 | $7700.00 | Window Closed / Lapsed |