US5164566A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for fluxless solder reflow
Assignee: Microelectronics and Computer Technology Corp
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Filing: 1990-06-12
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Granted: 1992-11-17
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Expires: 2010-06-12
Abstract
Abstract A method for reflowing solder without flux includes the steps of placing a first metallic element in contact with a second, solder-plated element, thereby defining a bond site; and causing a laser beam to impinge on the bond site. An apparatus for performing the above method is also disclosed.
Inventors
- 👤 Philip J. Spletter
- 👤 Claire T. Galanakis
- 👤 William G. Flynn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:24
CPC Classifications
B; B23; B23K; B23K1/00; B23K1/005; B23K1/0056; H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/341; H05K3/3421; H05K3/3494; H10; H10W; H10W72/00; H10W72/071; H10W72/072; H10W72/07231; H10W72/07235; H10W72/07236; H10W72/07251; H10W72/077; H10W72/20; H10W72/251; H10W72/252
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
40 words
A method of soldering without the need for fluxing agents, comprising the steps of: creating a bond site having solder thereat; causing a pulsed laser beam to impinge upon said bond site; and reflowing said solder at said bond site.
Claim 2
Independent Claim
40 words
A method of soldering without the need for fluxing agents, comprising the steps of: creating a bond site having solder thereat; causing a pulsed laser beam to impinge upon said bond site; and reflowing said solder at said bond site.
Claim 3
Dependent Claim
26 words
The method of claim 1 wherein said bond site comprises a first surface with solder thereon and a second surface placed in contact with said solder.
Claim 4
Dependent Claim
23 words
The method of claim 2 wherein said first surface and said second surface are solder joined together without a need for post-soldering cleaning.
Claim 5
Dependent Claim
29 words
The method of claim 1 wherein said step of causing a pulsed laser beam to impinge comprises the step of generating a laser beam with a pulsed YAG laser.
Claim 6
Dependent Claim
17 words
The method of claim 4 wherein said pulsed YAG laser beam is focused on said bond site.
Claim 7
Dependent Claim
24 words
The method of claim 5 wherein said pulsed YAG laser beam is caused to deliver in the range of 40-660 millijoules of total energy.
Claim 8
Dependent Claim
24 words
The method of claim 6 wherein said pulsed YAG laser beam is caused to deliver in the range of 150-400 millijoules of total energy.
Claim 9
Dependent Claim
14 words
The method of claim 2 wherein said first surface comprises a printed wiring board.
Claim 10
Dependent Claim
16 words
The method of claim 8 wherein said first surface further comprises at least one copper trace.
Claim 11
Dependent Claim
17 words
The method of claim 9 wherein tin/lead solder is disposed on said at least one copper trace.
Claim 12
Independent Claim
42 words
A method for reflowing solder without flux, said method comprising the steps of: placing a first metallic element in contact with a second, solder-plated element, thereby defining a bond site; and causing a pulsed laser beam to impinge upon said bond site.
Claim 13
Independent Claim
42 words
A method for reflowing solder without flux, said method comprising the steps of: placing a first metallic element in contact with a second, solder-plated element, thereby defining a bond site; and causing a pulsed laser beam to impinge upon said bond site.
Claim 14
Dependent Claim
10 words
The method of claim 11 wherein said solder comprises tin.
Claim 15
Dependent Claim
11 words
The method of claim 12 wherein said solder further comprises lead.
Claim 16
Dependent Claim
14 words
The method of claim 13 wherein said tin/lead solder is reflowed prior to bonding.
Claim 17
Independent Claim
40 words
An apparatus for reflowing solder without flux comprising: means for placing a first surface in contact with a second, solder-plated surface, thereby defining a bond site; and means for causing a pulsed laser beam to impinge upon said bond site.
Claim 18
Independent Claim
40 words
An apparatus for reflowing solder without flux comprising: means for placing a first surface in contact with a second, solder-plated surface, thereby defining a bond site; and means for causing a pulsed laser beam to impinge upon said bond site.
Claim 19
Dependent Claim
16 words
The apparatus of claim 15 wherein said pulsed laser beam is output by a YAG laser.
Claim 20
Dependent Claim
11 words
The apparatus of claim 16 wherein said YAG laser is pulsed.
Claim 21
Dependent Claim
20 words
The apparatus of claim 17 wherein said output energy of said pulsed YAG laser is in the range 40-660 millijoules.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-11-17 | 1996-05-18 | 1996-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-11-17 | 2000-05-18 | 2000-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-11-17 | 2004-05-18 | 2004-11-17 | $7700.00 | Window Closed / Lapsed |