Patent US5083007A successfully refreshed from Google Patents.
US5083007A
Expired / Lapsed
US
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Bonding metal electrical members with a frequency doubled pulsed laser beam
Assignee: Microelectronics and Computer Technology Corp
•
Filing: 1990-08-01
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Granted: 1992-01-21
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Expires: 2010-08-01
Abstract
Abstract Metal electrical members bonded by coupling to at least one member a frequency doubled pulsed Nd:YAG laser comprising 533 and 1064 nm wavelengths is described. Frequency doubling is accomplished by directing a 1064 nm wavelength pulsed Nd:YAG laser at an intracavity nonlinear crystal such as potassium titanyl phosphate between a highly reflective mirror and a partially reflective mirror to produce frequency doubling. An infrared reflector outside the cavity can reduce the 1064 nm wavelength thereby increasing the percentage of 533 nm wavelength. Alternatively the laser beam can be split and the separate wavelengths directed to separate attenuators to allow the percentage of both 533 nm and 1064 nm wavelengths to be adjusted. A gold bump on an integrated circuit can be bonded to a gold plated copper TAB tape lead.
Inventors
- 👤 Philip J. Spletter
- 👤 Rama R. Goruganthu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:10
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/106; H01S3/108; H01S3/109; B; B23; B23K; B23K26/00; B23K26/02; B23K26/06; B23K26/0604; B23K26/0613; B23K26/062; B23K26/0622; B23K26/067; H01S3/09; H01S3/091; H01S3/0915; H01S3/092; H01S3/093; H01S3/0931; H01S3/23; H01S3/2383
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
71 words
A method for laser bonding electrical members, comprising: contacting first and second metal electrical members to form a bond interface therebetween; generating a pulsed laser beam comprising a first wavelength and a second wavelength between 300-600 nm measuring one-half the first wavelength; and directing the pulsed laser beam to focus upon and couple to at least one of the members, thereby bonding the first and second members at the bond interface.
Claim 2
Independent Claim
71 words
A method for laser bonding electrical members, comprising: contacting first and second metal electrical members to form a bond interface therebetween; generating a pulsed laser beam comprising a first wavelength and a second wavelength between 300-600 nm measuring one-half the first wavelength; and directing the pulsed laser beam to focus upon and couple to at least one of the members, thereby bonding the first and second members at the bond interface.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein said at least 3% of the total beam energy is at least 3 millijoules.
Claim 4
Dependent Claim
18 words
The method of claim 2 wherein said at least one of the members comprises copper, gold or tin.
Claim 5
Dependent Claim
22 words
The method of claim 3 wherein said pulsed laser beam includes a pulsed solid state laser beam with 1064 nm wavelength radiation.
Claim 6
Independent Claim
67 words
A method for laser bonding electrical members, comprising: contacting first and second metal electrical members to form a bond interface therebetween; and directing a frequency doubled pulsed solid state laser beam comprising a first wavelength and a second wavelength measuring one-half the first wavelength to focus upon and couple to at least one of the members, thereby bonding the first and second members at the bond interface.
Claim 7
Independent Claim
67 words
A method for laser bonding electrical members, comprising: contacting first and second metal electrical members to form a bond interface therebetween; and directing a frequency doubled pulsed solid state laser beam comprising a first wavelength and a second wavelength measuring one-half the first wavelength to focus upon and couple to at least one of the members, thereby bonding the first and second members at the bond interface.
Claim 8
Dependent Claim
28 words
The method of claim 5 wherein the frequency doubled pulsed laser beam comprises a first wavelength of about 1064 nm and a second wavelength of about 533 nm.
Claim 9
Dependent Claim
41 words
The method of claim 6 further comprising the steps of: generating a 1064 nm wavelength pulsed solid state laser beam, and directing the pulsed 1064 nm wavelength laser beam at a nonlinear crystal to produce the frequency doubled pulsed laser beam.
Claim 10
Dependent Claim
27 words
The method of claim 7 wherein the nonlinear crystal is selected from the group consisting of lithium iodate, lithium niobate, potassium titanyl phosphate and beta barium borate.
Claim 11
Dependent Claim
27 words
The method of claim 7 wherein the first member is a metal bonding pad on an integrated circuit and the second member is a TAB tape lead.
Claim 12
Dependent Claim
20 words
The method of claim 9 wherein the bonding pad is gold and the TAB tape lead is gold plated copper.
Claim 13
Dependent Claim
21 words
The method of claim 7 wherein the frequency doubled laser pulses have a total pulse energy of at least 30 millijoules.
Claim 14
Dependent Claim
15 words
The method of claim 7 wherein the pulse time is between 0.5 and 5.0 milliseconds.
Claim 15
Dependent Claim
15 words
The method of claim 7 wherein the pulse time is between 0.6 and 1.75 milliseconds.
Claim 16
Dependent Claim
19 words
The method of claim 7 wherein the 533 nm wavelength forms at least 3% of the laser beam power.
Claim 17
Dependent Claim
18 words
The method of claim 14 wherein the 533 nm wavelength forms between 3%-33% of the laser beam power.
Claim 18
Dependent Claim
18 words
The method of claim 7 wherein said at least one of the members comprises copper, gold or tin.
Claim 19
Dependent Claim
21 words
The method of claim 7 wherein upon coupling to a member the total pulse energy is between 3 and 150 millijoules.
Claim 20
Dependent Claim
21 words
The method of claim 7 wherein the upon coupling to a member average pulse power is between 6 and 250 watts.
Claim 21
Dependent Claim
32 words
The method of claim 7 wherein upon coupling to a member the total pulse energy is between 3 and 150 millijoules, and the average pulse power is between 6 and 250 watts.
Claim 22
Dependent Claim
15 words
The method of claim 7 wherein the generated laser beam is a Nd:YAG laser beam.
Claim 23
Dependent Claim
15 words
The method of claim 7 wherein the generated laser beam is a Nd:YLF laser beam.
Claim 24
Dependent Claim
15 words
The method of claim 7 wherein the generated laser beam is a Nd:YAP laser beam.
Claim 25
Independent Claim
114 words
A method of laser bonding electrical members, comprising: contacting first and second metal electrical members to form a bond interface therebetween; generating a 1064 nm wavelength pulsed solid state laser beam; directing the 1064 nm wavelength pulsed laser beam at a nonlinear crystal to produce a frequency doubled pulsed laser beam comprising 1064 nm and 533 nm wavelengths; directing the frequency doubled pulsed laser beam at an infrared reflector to reduce but not eliminate the 1064 nm wavelength power in the laser beam; and directing the frequency doubled pulsed laser beam to focus upon and couple to at least one of the members, thereby bonding the first and second members at the bond interface.
Claim 26
Independent Claim
114 words
A method of laser bonding electrical members, comprising: contacting first and second metal electrical members to form a bond interface therebetween; generating a 1064 nm wavelength pulsed solid state laser beam; directing the 1064 nm wavelength pulsed laser beam at a nonlinear crystal to produce a frequency doubled pulsed laser beam comprising 1064 nm and 533 nm wavelengths; directing the frequency doubled pulsed laser beam at an infrared reflector to reduce but not eliminate the 1064 nm wavelength power in the laser beam; and directing the frequency doubled pulsed laser beam to focus upon and couple to at least one of the members, thereby bonding the first and second members at the bond interface.
Claim 27
Dependent Claim
27 words
The method of claim 23 wherein the nonlinear crystal is selected from the group consisting of lithium iodate, lithium niobate, potassium titanyl phosphate and beta barium borate.
Claim 28
Dependent Claim
34 words
The method of claim 23 wherein after passing through the infrared reflector the frequency doubled pulsed laser beam energy comprises at least 3%-33% at 533 nm wavelength with the remainder at 1064 nm wavelength.
Claim 29
Dependent Claim
32 words
The method of claim 23 wherein upon coupling to a member the total pulse energy is between 3 and 150 millijoules and the average pulse power is between 6 and 250 watts.
Claim 30
Dependent Claim
12 words
The method of claim 23 wherein the laser is a Nd:YAG laser.
Claim 31
Independent Claim
164 words
An apparatus for generating a frequency doubled pulsed Nd:YAG laser, comprising: a laser cavity; means for generating a 1064 wavelength pulsed Nd:YAG laser beam in the cavity; means for frequency doubling the Nd:YAG laser beam in the cavity, wherein 1064 nm wavelength radiation is input and 533 nm and 1064 nm wavelengths radiation are output; first and second reflector means at opposite ends of the cavity for reflecting the laser beam back and forth, wherein the second reflector means releases a frequency doubled pulsed Nd:YAG laser beam comprising 533 nm and 1964 nm wavelength radiation with at least 3 millijoules of 533 nm wavelength radiation; means for separating the 533 nm and 1064 nm wavelengths; means for attenuating the separated 533 nm wavelength; means for attenuating the separated 1064 nm wavelength; and means for combining the separated and attenuated 533 nm and 1064 nm wavelengths, thereby allowing the percentage of 533 nm and 1064 nm wavelength radiation in the laser beam to be adjusted.
Claim 32
Independent Claim
164 words
An apparatus for generating a frequency doubled pulsed Nd:YAG laser, comprising: a laser cavity; means for generating a 1064 wavelength pulsed Nd:YAG laser beam in the cavity; means for frequency doubling the Nd:YAG laser beam in the cavity, wherein 1064 nm wavelength radiation is input and 533 nm and 1064 nm wavelengths radiation are output; first and second reflector means at opposite ends of the cavity for reflecting the laser beam back and forth, wherein the second reflector means releases a frequency doubled pulsed Nd:YAG laser beam comprising 533 nm and 1964 nm wavelength radiation with at least 3 millijoules of 533 nm wavelength radiation; means for separating the 533 nm and 1064 nm wavelengths; means for attenuating the separated 533 nm wavelength; means for attenuating the separated 1064 nm wavelength; and means for combining the separated and attenuated 533 nm and 1064 nm wavelengths, thereby allowing the percentage of 533 nm and 1064 nm wavelength radiation in the laser beam to be adjusted.
Claim 33
Independent Claim
211 words
An apparatus for generating a frequency doubled pulsed Nd:YAG laser, comprising: a Nd:YAG cavity with first and second opposite ends; a photonic energy source for generating a 1064 nm wavelength pulsed Nd:YAG laser beam inside the cavity; a nonlinear crystal inside the cavity for frequency doubling the pulsed Nd:YAG laser beam, wherein 1064 nm wavelength radiation is input and 533 nm and 1064 nm wavelength radiation is output; a first highly reflective reflector mirror positioned at the first end of the cavity; a second partially reflective reflector mirror positioned at the second end of the cavity opposite the first mirror, wherein the laser beam is reflected back and forth between the first and second mirrors and through the nonlinear crystal therebetween, and a frequency doubled pulsed Nd:YAG laser beam comprising 533 nm and 1064 nm wavelength radiation with at least 3 millijoules at 533 nm wavelength is released from the cavity through the second mirror; means for separating the 533 and 1064 nm wavelengths; means for attenuating the separated 533 nm wavelength; means for attenuating the separated 1064 nm wavelength; and means for combining the separated and attenuated 533 and 1064 nm wavelengths, thereby allowing the percentage of 533 nm and 1064 nm wavelengths in the laser beam to be adjusted.
Claim 34
Independent Claim
211 words
An apparatus for generating a frequency doubled pulsed Nd:YAG laser, comprising: a Nd:YAG cavity with first and second opposite ends; a photonic energy source for generating a 1064 nm wavelength pulsed Nd:YAG laser beam inside the cavity; a nonlinear crystal inside the cavity for frequency doubling the pulsed Nd:YAG laser beam, wherein 1064 nm wavelength radiation is input and 533 nm and 1064 nm wavelength radiation is output; a first highly reflective reflector mirror positioned at the first end of the cavity; a second partially reflective reflector mirror positioned at the second end of the cavity opposite the first mirror, wherein the laser beam is reflected back and forth between the first and second mirrors and through the nonlinear crystal therebetween, and a frequency doubled pulsed Nd:YAG laser beam comprising 533 nm and 1064 nm wavelength radiation with at least 3 millijoules at 533 nm wavelength is released from the cavity through the second mirror; means for separating the 533 and 1064 nm wavelengths; means for attenuating the separated 533 nm wavelength; means for attenuating the separated 1064 nm wavelength; and means for combining the separated and attenuated 533 and 1064 nm wavelengths, thereby allowing the percentage of 533 nm and 1064 nm wavelengths in the laser beam to be adjusted.
Claim 35
Dependent Claim
27 words
The apparatus of claim 29 wherein the nonlinear crystal is selected from the group consisting of lithium iodate, lithium niobate, potassium titanyl phosphate and beta barium borate.
Claim 36
Independent Claim
180 words
An apparatus for generating a frequency doubled pulsed Nd:YAG laser, comprising: a Nd:YAG cavity with first and second opposite ends; a photonic energy source for generating a 1064 nm wavelength pulsed Nd:YAG laser beam inside the cavity; a nonlinear crystal inside the cavity for frequency doubling the pulsed Nd:YAG laser beam, wherein 1064 nm wavelength radiation is input and 533 nm and 1064 nm wavelength radiation is output; a first highly reflective reflector mirror positioned at the first end of the cavity; a second partially reflective reflector mirror positioned at the second end of the cavity opposite the first mirror, wherein the laser beam is reflected back and forth between the first and second mirrors and through the nonlinear crystal therebetween, and a frequency doubled pulsed Nd:YAG laser beam comprising 533 nm and 1064 nm wavelength radiation with at least 3 millijoules at 533 nm wavelength is released from the cavity through the second mirror; and an infrared reflector to which the laser beam is directed for reducing but not eliminating the 1064 nm wavelength power in the laser beam.
Claim 37
Independent Claim
180 words
An apparatus for generating a frequency doubled pulsed Nd:YAG laser, comprising: a Nd:YAG cavity with first and second opposite ends; a photonic energy source for generating a 1064 nm wavelength pulsed Nd:YAG laser beam inside the cavity; a nonlinear crystal inside the cavity for frequency doubling the pulsed Nd:YAG laser beam, wherein 1064 nm wavelength radiation is input and 533 nm and 1064 nm wavelength radiation is output; a first highly reflective reflector mirror positioned at the first end of the cavity; a second partially reflective reflector mirror positioned at the second end of the cavity opposite the first mirror, wherein the laser beam is reflected back and forth between the first and second mirrors and through the nonlinear crystal therebetween, and a frequency doubled pulsed Nd:YAG laser beam comprising 533 nm and 1064 nm wavelength radiation with at least 3 millijoules at 533 nm wavelength is released from the cavity through the second mirror; and an infrared reflector to which the laser beam is directed for reducing but not eliminating the 1064 nm wavelength power in the laser beam.
Claim 38
Dependent Claim
12 words
The method of claim 1, wherein the pulsed laser is not Q-switched.
Claim 39
Dependent Claim
32 words
The method of claim 1, wherein before the temperature of said at least one of the members increases, the second wavelength provides significantly more absorption of laser energy than the first wavelength.
Claim 40
Dependent Claim
32 words
The method of claim 33, wherein as the temperature of said at least one of the members increases, the optical absorption of said at least one of the members increases as well.
Claim 41
Dependent Claim
14 words
The method of claim 34, wherein said bonding step comprises welding the members together.
Claim 42
Dependent Claim
19 words
The method of claim 35, wherein the first wavelength is 1064 nm and the second wavelength is 533 nm.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1995-01-20 | 1995-07-22 | 1996-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-01-20 | 1999-07-22 | 2000-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-01-20 | 2003-07-22 | 2004-01-21 | $7700.00 | Window Closed / Lapsed |