Patent US2023423A successfully refreshed from Google Patents.
US4925083A
Expired / Lapsed
US
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Ball bonding method and apparatus for performing the method
Assignee: F&K Delvotec Bondtechnik GmbH
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Filing: 1987-12-09
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Granted: 1990-05-15
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Expires: 2007-12-09
Abstract
Abstract A ball bonding method and apparatus is disclosed including gold wire bonding. The steps include positioning and lowering a bond capillary (10) with a bond wire (11) including a flame-scarfed bond wire ball (12) downwardly onto a first bonding pad (17). The bond wire ball (12) is welded by heating and applying a bonding pressure or ultrasonic, or both. The bond capillary (10) is raised and moved to form a loop (21), followed by the step of welding the bond wire (11) to a second bonding pad (16) using heating and applying pressure, ultrasonic or both. The bond capillary (10) is raised to a tail-length position (29) and the bond wire (11) is broken by a vertical pulling force created by closing a clamp (13) onto the wire and raising the clamp (13) engaging the bond wire (11). The end of the free bond wire is flame-scarfed to form a bond wire ball (12). For the flame-scarfing, the distance travelled by the wire clamp (13) until the bond wire (11) breaks is measured and the flame-scarfing lance (18) is accurately adjusted, or the free wire end after breakage is accurately adjusted.
Inventors
- 👤 Farhad Farassat
- 👤 Walter Birgel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 03:40
CPC Classifications
B; B23; B23K; B23K20/00; B23K20/002; B23K20/004; B23K20/005; B23K20/007; H; H10; H10W; H10W72/00; H10W72/071; H10W72/0711; H10W72/075; H10W72/01; H10W72/015; H10W72/01551; H10W72/07141; H10W72/07502; H10W72/07511; H10W72/07521; H10W72/07531; H10W72/07532; H10W72/07533; H10W72/50; H10W72/531; H10W72/536; H10W72/5363; H10W72/551; H10W72/552; H10W72/5522; H10W90/00; H10W90/701; H10W90/751; H10W90/754; H10W90/756
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
246 words
A ball bonding method including the working steps of: (a) positioning and lowering a bond capillary including a flame-scarfed bond wire ball from an upwardly retracted starting position onto a first bonding pad; (b) welding the bond wire ball by heating and applying a defined bonding pressure and/or ultrasonic assistance; (c) upward-retracting of the bond capillary; (d) forming a loop in the bond wire; (e) welding the bond wire in spaced relation to the bond wire ball to a second bonding pad by heating and applying a defined bonding pressure and/or ultrasonic assistance; (f) upward-retracting of the bond capillary to a predetermined tail-length position, clamping and pulling on said bond wire to break the bond wire; and subsequent upward-retracting of the bond capillary to said starting position; and (g) flame-scarfing the free bond wire end to form a fresh bond wire ball; and the improvement comprising the steps of (h) applying a voltage between said second bonding pad and said clamp exerting said pulling force on the bond wire as soon as the clamp is in the wire clamping position; (i) measuring the distance travelled by the clamp until breakage of the bond wire in accordance with interruption of the electrical connection between the second bonding pad and the clamp, and; (j) locating a flame-scarfing device spaced from the free bond wire end in accordance with distance travelled by the clamp and thereby spacing the flame-scarfing device a predetermined distance from the free bond wire end.
Claim 2
Dependent Claim
246 words
A ball bonding method including the working steps of: (a) positioning and lowering a bond capillary including a flame-scarfed bond wire ball from an upwardly retracted starting position onto a first bonding pad; (b) welding the bond wire ball by heating and applying a defined bonding pressure and/or ultrasonic assistance; (c) upward-retracting of the bond capillary; (d) forming a loop in the bond wire; (e) welding the bond wire in spaced relation to the bond wire ball to a second bonding pad by heating and applying a defined bonding pressure and/or ultrasonic assistance; (f) upward-retracting of the bond capillary to a predetermined tail-length position, clamping and pulling on said bond wire to break the bond wire; and subsequent upward-retracting of the bond capillary to said starting position; and (g) flame-scarfing the free bond wire end to form a fresh bond wire ball; and the improvement comprising the steps of (h) applying a voltage between said second bonding pad and said clamp exerting said pulling force on the bond wire as soon as the clamp is in the wire clamping position; (i) measuring the distance travelled by the clamp until breakage of the bond wire in accordance with interruption of the electrical connection between the second bonding pad and the clamp, and; (j) locating a flame-scarfing device spaced from the free bond wire end in accordance with distance travelled by the clamp and thereby spacing the flame-scarfing device a predetermined distance from the free bond wire end.
Claim 3
Dependent Claim
37 words
The method as claimed in claim 1 including moving said clamp which serves to break the bond wire welded to the second bonding pad in a step-wise sequence and counting the steps until the bond wire breaks.
Claim 4
Dependent Claim
21 words
The method as claimed in claim 2 including resetting of the counting of the steps to zero after the wire breaks.
Claim 5
Dependent Claim
220 words
A ball bonding method including (a) lowering a bond capillary including a wire having a flame-scarfed bond wire ball from an upwardly retracted starting position onto a first bonding pad; and (b) heating said ball and applying bonding pressure and/or ultrasonic force to the ball and pad to weld the ball to the pad; and (c) raising and moving the bond capillary and wire to form a loop aligned with a second bonding pad; (d) welding the bond wire to said second bonding pad including heating and applying bonding pressure and/or ultrasonic force; (e) upward-retracting of the bond capillary to a predetermined tail-length position, breaking of the bond wire by subjecting it to a pulling force by means of a clamp engaging the bond wire, and further upwardretraction to the starting position; and (f) flame-scarfing the free bond wire end to form a fresh bond wire ball; the improvement comprising the steps of (g) locating a flame-scarfing device in the flame-scarfing position prior to flame-scarfing of the free bond wire end; and (h) subsequent to said locating of said device lowering of the bond capillary until the free bond wire end contacts a reference element and then raising the bond capillary a predetermined distance to locate the free bond wire end in a predetermined spacing from the flame scarfing device.
Claim 6
Dependent Claim
220 words
A ball bonding method including (a) lowering a bond capillary including a wire having a flame-scarfed bond wire ball from an upwardly retracted starting position onto a first bonding pad; and (b) heating said ball and applying bonding pressure and/or ultrasonic force to the ball and pad to weld the ball to the pad; and (c) raising and moving the bond capillary and wire to form a loop aligned with a second bonding pad; (d) welding the bond wire to said second bonding pad including heating and applying bonding pressure and/or ultrasonic force; (e) upward-retracting of the bond capillary to a predetermined tail-length position, breaking of the bond wire by subjecting it to a pulling force by means of a clamp engaging the bond wire, and further upwardretraction to the starting position; and (f) flame-scarfing the free bond wire end to form a fresh bond wire ball; the improvement comprising the steps of (g) locating a flame-scarfing device in the flame-scarfing position prior to flame-scarfing of the free bond wire end; and (h) subsequent to said locating of said device lowering of the bond capillary until the free bond wire end contacts a reference element and then raising the bond capillary a predetermined distance to locate the free bond wire end in a predetermined spacing from the flame scarfing device.
Claim 7
Dependent Claim
17 words
The method as claimed in claim 4 including sensing the contacting of the free bond wire end.
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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) | 1993-05-14 | 1993-11-13 | 1994-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-14 | 1997-11-13 | 1998-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-14 | 2001-11-13 | 2002-05-15 | $7700.00 | Window Closed / Lapsed |