US3790738A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulsed heat eutectic bonder
Assignee: WELDMATIC CORP
•
Filing: 1972-05-30
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Granted: 1974-02-05
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Expires: 1992-05-30
Abstract
Abstract A pulsed heat hybrid semiconductor die bonding apparatus utilizing a pair of heating electrodes which bracket a die collet and contact the substrate area immediately adjacent each side of the die or chip to be bonded. A heating pulse of a predetermined magnitude and duration produces localized substrate heating via a discharge of current to the metalization under the chip. A conductivity monitor connected to the electrodes indicates the quality of the electrical contact of the heating electrodes with the substrate. Simultaneous with the substrate heating current pulse, a low frequency, unidirectional mechanical scrubbing motion is applied to the arm holding the die collet. The arm is supported in the apparatus by means of a flexure type of mounting. The combination of heating current applied to the substrate in pulses with scrubbing action precisely controls the heating and eutectic bonding of the substrate and chip, preventing subsequent unbonding or heat damage to the semiconductor die. The bonding arm mechanism accepts quickly interchangeable, floating die collet tools.
Inventors
- 👤 J Laub
- 👤 D Griffiths
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:54
CPC Classifications
B; B23; B23K; B23K20/00; B23K20/02; B23K20/023; B23K11/00; B23K11/10; B23K11/12
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
164 words
A pulse heated eutectic bonding apparatus for attaching semiconductor dies to a metalized substrate of material comprising: a housing; a die pickup and bonding tool; a bonding arm connected to and supported by the housing; a holder for the tool supported by the bonding arm; electrode means supported by the bonding arm adjacent the bonding tool for selectively contacting and supplying heating current to the substrate area at the die attachment location during the interval of contact of the bonding tool with the substrate area; electric power supply means; means interconnecting the power supply and the electrodes for supplying an electric current heating pulse to the electrode means during the bonding interval to raise the substrate area to a eutectic bonding temperature; electromagnetic vibrating means coupled between the bonding arm and the holder for vibrating the tool at a predetermined frequency during the heating of the substrate; and control means for producing the heating pulse and vibration simultaneously for a predetermined length of time.
Claim 2
Dependent Claim
164 words
A pulse heated eutectic bonding apparatus for attaching semiconductor dies to a metalized substrate of material comprising: a housing; a die pickup and bonding tool; a bonding arm connected to and supported by the housing; a holder for the tool supported by the bonding arm; electrode means supported by the bonding arm adjacent the bonding tool for selectively contacting and supplying heating current to the substrate area at the die attachment location during the interval of contact of the bonding tool with the substrate area; electric power supply means; means interconnecting the power supply and the electrodes for supplying an electric current heating pulse to the electrode means during the bonding interval to raise the substrate area to a eutectic bonding temperature; electromagnetic vibrating means coupled between the bonding arm and the holder for vibrating the tool at a predetermined frequency during the heating of the substrate; and control means for producing the heating pulse and vibration simultaneously for a predetermined length of time.
Claim 3
Dependent Claim
27 words
A bonding apparatus according to claim 1 including monitoring means electrically coupled to the electrode means for sensing electrical contact between the substrate and the electrode means.
Claim 4
Dependent Claim
44 words
A bonding apparatus according to claim 2 including a flexure linkage coupling the vibrating means between the bonding arm and the holder, the flexure linkage being deflectable in the direction of the vibrating action and rigid in the direction transverse to the vibrating action.
Claim 5
Dependent Claim
31 words
A bonding apparatus according to claim 3 wherein the flexure linkage includes a pair of flexures vertically oriented in a parallelogram configuration for transmitting horizontal vibrations to the holder and tool.
Claim 6
Dependent Claim
37 words
A bonding apparatus according to claim 4 wherein the electromagnetic vibrating means includes a permanent magnet secured to the holder and a solenoid secured to a frame member of the apparatus in operative relation with the magnet.
Claim 7
Dependent Claim
39 words
A bonding apparatus according to claim 5 including means for controlling the amplitude and frequency of an excitation signal applied to the solenoid for controlling the amplitude and frequency of motion of the magnet and vibration of the tool.
Claim 8
Dependent Claim
52 words
A bonding apparatus according to claim 6 wherein the electrode means include a first and second electrode supported by the bonding arm and located on opposite sides of the tool, the electrodes having at least one extended dimension for producing an evenly distributed electric current density in the substrate beneath the die.
Claim 9
Dependent Claim
36 words
A bonding apparatus according to claim 7 wherein the pickup and bonding tool is retained in a slip fit mounting in the holder for floating action during bonding and easy insertion and removal from the holder.
Claim 10
Dependent Claim
29 words
A bonding apparatus according to claim 8 wherein the bonding tool includes a weight secured thereto for applying a predetermined amount of bonding force to the die during bonding.
Claim 11
Dependent Claim
61 words
A bonding apparatus according to claim 9 including a die pickup stage for storing dies to be bonded and a bonding stage for holding the substrate in position supported by the apparatus housing, the two stages being movable relative to the tool to permit selective location of the die pickup stage or substrate stage in precise alignment with the bonding tool.
Claim 12
Dependent Claim
26 words
A bonding apparatus according to claim 10 wherein the pickup stage and bonding stage are supported on a common manipulator platform mounted on the apparatus housing.
Claim 13
Dependent Claim
23 words
A bonding apparatus according to claim 11 including selectively applied air bearing means for slidably supporting the manipulator platform on the bonding apparatus.
Claim 14
Dependent Claim
16 words
A bonding apparatus according to claim 12 including means for heating the pickup and bonding tool.
Claim 15
Dependent Claim
16 words
A bonding apparatus according to claim 13 including auxiliary heating means for heating the bonding stage.
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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) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |