US3846905A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Assembly method for semiconductor chips
Assignee: Texas Instruments Inc
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Filing: 1973-07-09
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Granted: 1974-11-12
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Expires: 1993-07-09
Abstract
Abstract A method is described in the assembly of integrated circuits that utilizes laser scribing while protecting the integrated circuit components and which enables use of automated machineoriented bonding techniques. The method includes aligning a slice of semiconductor material so that the integrated circuits thereon are oriented in a desired manner, the surface of the integrated circuits being covered with a protective wax and secured to a support. Infrared radiation is utilized to align the slice and to illuminate the scribe lines so they are detectable from the back surface of the slice. The slice is then separated along the scribe lines by partially cutting the slice from the back surface of the slice with a laser, the front surface of the slice being protected from the slag produced by the cutting action of the laser. Contacts on the respective chips are then bonded to metal leads by a method which enables utilization of a constant temperature source.
Inventors
- 👤 J Harper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:47
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0446; H10W; H10W70/00; H10W70/60; H10W70/67; H10W70/688
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
153 words
A method for bonding a metal lead which is formed on one surface of a plastic strip to extend over an edge of an aperture therethrough to a contact on a surface of a semiconductor body comprising the steps of: a. positioning said lead adjacent a support which is maintained at a constant elevated temperature sufficient for alloying said lead to said contact; b. aligning said semiconductor body with said aperture in said plastic strip such that said contact directly overlies said metal lead; c. inserting said body through said aperture such that said contact deflects said lead into thermal contact with said support, thereby heating said lead and said contact to alloy a portion of said lead to said contact; and d. withdrawing said body from said aperture, the tension of said deflected lead maintaining contact between said lead and said contact during the interval required for said alloyed portion to solidify.
Claim 2
Independent Claim
153 words
A method for bonding a metal lead which is formed on one surface of a plastic strip to extend over an edge of an aperture therethrough to a contact on a surface of a semiconductor body comprising the steps of: a. positioning said lead adjacent a support which is maintained at a constant elevated temperature sufficient for alloying said lead to said contact; b. aligning said semiconductor body with said aperture in said plastic strip such that said contact directly overlies said metal lead; c. inserting said body through said aperture such that said contact deflects said lead into thermal contact with said support, thereby heating said lead and said contact to alloy a portion of said lead to said contact; and d. withdrawing said body from said aperture, the tension of said deflected lead maintaining contact between said lead and said contact during the interval required for said alloyed portion to solidify.
Claim 3
Dependent Claim
319 words
An automated method for sequentially bonding electrical contacts on semiconductor chips to corresponding sets of metal leads on a continuous plastic strip wherein said plastic strip has a plurality of apertures therein for respectively receiving a semiconductor chip, each aperture having associated therewith a set of metal leads which are formed on one surface of said strip adjacent each aperture, a portion of each lead extending over an edge of the aperture, comprising the steps of: a. positioning said strip such that a first aperture overlies a support which is maintained at a constant temperature which is sufficient for alloying said electrical contacts to corresponding set of leads, said one surface of said strip disposed adjacent the surface of said support. b. aligning a first semiconductor chip over said first aperture, the electrical contacts on said chip adjacent and in alignment with a set of corresponding leads; c. inserting said first chip through first aperture such that said contacts deflect said set of leads into thermal contact with said support, thereby allowing a portion of each lead to its corrEsponding contact; d. withdrawing said chip from said aperture, the tension of said deflected leads maintaining contact between said ends and said contacts during the interval required for said alloy portions to solidify; e. positioning said strip such that a second aperture and its corresponding set of leads overlies said support; f. aligning a second semiconductor chip over said second aperture and inserting it through said second aperture such that the electrical contacts on said second chip deflect said corresponding set of leads associated with said second aperture into thermal contact with said support to effect alloying a portion of each lead to its associated contact; and g. withdrawing said second chip from said second aperture, the tension of said deflected leads maintaining contact between said leads and said contacts during the interval required for said alloyed portions to solidify.
Claim 4
Dependent Claim
319 words
An automated method for sequentially bonding electrical contacts on semiconductor chips to corresponding sets of metal leads on a continuous plastic strip wherein said plastic strip has a plurality of apertures therein for respectively receiving a semiconductor chip, each aperture having associated therewith a set of metal leads which are formed on one surface of said strip adjacent each aperture, a portion of each lead extending over an edge of the aperture, comprising the steps of: a. positioning said strip such that a first aperture overlies a support which is maintained at a constant temperature which is sufficient for alloying said electrical contacts to corresponding set of leads, said one surface of said strip disposed adjacent the surface of said support. b. aligning a first semiconductor chip over said first aperture, the electrical contacts on said chip adjacent and in alignment with a set of corresponding leads; c. inserting said first chip through first aperture such that said contacts deflect said set of leads into thermal contact with said support, thereby allowing a portion of each lead to its corrEsponding contact; d. withdrawing said chip from said aperture, the tension of said deflected leads maintaining contact between said ends and said contacts during the interval required for said alloy portions to solidify; e. positioning said strip such that a second aperture and its corresponding set of leads overlies said support; f. aligning a second semiconductor chip over said second aperture and inserting it through said second aperture such that the electrical contacts on said second chip deflect said corresponding set of leads associated with said second aperture into thermal contact with said support to effect alloying a portion of each lead to its associated contact; and g. withdrawing said second chip from said second aperture, the tension of said deflected leads maintaining contact between said leads and said contacts during the interval required for said alloyed portions to solidify.
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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) | 1977-11-11 | 1978-05-13 | 1978-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-11 | 1982-05-13 | 1982-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-11 | 1986-05-13 | 1986-11-12 | $7700.00 | Window Closed / Lapsed |