US5609290A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluxless soldering method
Assignee: University of North Carolina at Charlotte
•
Filing: 1995-04-20
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Granted: 1997-03-11
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Expires: 2015-04-20
Abstract
Abstract A fluxless soldering method utilizing a strongly internally bonded fluorine containing gas such as hydrogen fluoride (HF). The solder surface is exposed to the gas in place of a flux treatment, resulting in a modified surface layer which allows reflow or joining for an extended period.
Inventors
- 👤 Stephen M. Bobbio
- 👤 Thomas D. DuBois
- 👤 Farid M. Tranjan
- 👤 George K. Lucey, Jr.
- 👤 James D. Geis
- 👤 Robert F. Lipscomb
- 👤 Timothy Piekarski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 00:15
CPC Classifications
B; B23; B23K; B23K1/00; B23K1/20
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
77 words
A fluxless soldering method, comprising: (a) selecting a strongly internally bonded fluorine-containing gas; and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas at a temperature of about 10°-250° C., wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein the surface is selected from the group consisting of solder precoated on a surface, tin, copper and gold.
Claim 2
Dependent Claim
77 words
A fluxless soldering method, comprising: (a) selecting a strongly internally bonded fluorine-containing gas; and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas at a temperature of about 10°-250° C., wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein the surface is selected from the group consisting of solder precoated on a surface, tin, copper and gold.
Claim 3
Dependent Claim
20 words
The method of claim 1, wherein the substance is solder when it is exposed to the strongly bonded fluorine-containing gas.
Claim 4
Dependent Claim
14 words
The method of claim 2, wherein the substance is solder precoated on a surface.
Claim 5
Dependent Claim
12 words
The method of claim 2, wherein the substance is a solder preform.
Claim 6
Dependent Claim
15 words
The method of claim 1, wherein the substance is a solder in a powder form.
Claim 7
Dependent Claim
12 words
The method of claim 1, wherein the substance is a molten solder.
Claim 8
Dependent Claim
142 words
A fluxless soldering method, comprising: (a) selecting a strongly internally bonded fluorine-containing gas; and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas, wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein said substance is selected from the group consisting of solder precoated on a surface, solder preform, solder in a powder form which will be incorporated in a solder paste at a future time, and molten solder and said surface is selected from the group consisting of: (a) solder precoated on a surface, tin, copper, and gold, which have been treated with said strongly internally bonded fluorine-containing gas; and (b) solder precoated on a surface, tin, copper, and gold, which have not been treated with said strongly internally bonded fluorine-containing gas.
Claim 9
Dependent Claim
142 words
A fluxless soldering method, comprising: (a) selecting a strongly internally bonded fluorine-containing gas; and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas, wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein said substance is selected from the group consisting of solder precoated on a surface, solder preform, solder in a powder form which will be incorporated in a solder paste at a future time, and molten solder and said surface is selected from the group consisting of: (a) solder precoated on a surface, tin, copper, and gold, which have been treated with said strongly internally bonded fluorine-containing gas; and (b) solder precoated on a surface, tin, copper, and gold, which have not been treated with said strongly internally bonded fluorine-containing gas.
Claim 10
Dependent Claim
117 words
A fluxless soldering method, comprising: (a) selecting a strongly internally bonded fluorine-containing gas; and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas, wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein said solder is selected from the group consisting of untreated solder precoated on a surface, untreated solder preform, untreated solder in a powder form which has been incorporated in a solder paste, and molten solder, and said surface is selected from the group consisting of solder precoated on a surface, tin, copper, and gold, which have been treated with said strongly internally bonded fluorine-containing gas.
Claim 11
Dependent Claim
117 words
A fluxless soldering method, comprising: (a) selecting a strongly internally bonded fluorine-containing gas; and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas, wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein said solder is selected from the group consisting of untreated solder precoated on a surface, untreated solder preform, untreated solder in a powder form which has been incorporated in a solder paste, and molten solder, and said surface is selected from the group consisting of solder precoated on a surface, tin, copper, and gold, which have been treated with said strongly internally bonded fluorine-containing gas.
Claim 12
Dependent Claim
15 words
The method of claim 1, wherein the strongly internally bonded fluorine-containing gas is hydrogen fluoride.
Claim 13
Dependent Claim
57 words
The method of claim 9, further comprising obtaining said hydrogen fluoride by a method selected from the group consisting of: (a) utilizing anhydrous HF; (b) evaporation from aqueous HF; (c) utilizing a chemical reaction to form HF; and (d) utilizing electrical discharge to form HF, where the HF is extracted from the discharge in the effluent flow.
Claim 14
Dependent Claim
116 words
The method of claim 10, wherein hydrogen fluoride is obtained by utilizing electrical discharge to form HF in an effluent, said electrical discharge being obtained by a method selected from the group consisting of: (a) glow discharge at low pressure where the discharge is produced by a component selected from the group consisting of: (i) an inductively coupled electrical generator; (ii) a capacitively coupled electrical generator; and (iii) a microwave generator; (b) high pressure discharge where the discharge is produced by a component selected from the group consisting of: (i) a corona discharge electrode; (ii) spark-gap electrodes; (iii) a gas filled plasma coupled electrode; (iv) an inductively coupled electrical generator; and (v) a focussed microwave generator.
Claim 15
Dependent Claim
16 words
The method of claim 1, wherein the method is performed at or near ambient atmospheric pressure.
Claim 16
Dependent Claim
18 words
The method of claim 12, wherein the method is performed at a pressure lower than ambient atmospheric pressure.
Claim 17
Dependent Claim
25 words
The method of claim 1, wherein the method is performed in an evacuated chamber at low pressure in the range where glow discharge can occur.
Claim 18
Dependent Claim
21 words
The method of claim 1, wherein the method is performed at an exposure time of between 0.5 minute and one hour.
Claim 19
Dependent Claim
19 words
The method according to claim 15, wherein the temperature is 80° C. and the exposure time is 1.5 minute.
Claim 20
Dependent Claim
13 words
The method according to claim 1, wherein said substance is tin lead solder.
Claim 21
Independent Claim
81 words
A method of improving soldering processes employing flux, comprising: (a) selecting a strongly internally bonded fluorine-containing gas; and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas at a temperature of about 10°-250° C., wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein the surface is selected from the group consisting of solder precoated on a surface, tin, copper and gold.
Claim 22
Independent Claim
81 words
A method of improving soldering processes employing flux, comprising: (a) selecting a strongly internally bonded fluorine-containing gas; and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas at a temperature of about 10°-250° C., wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein the surface is selected from the group consisting of solder precoated on a surface, tin, copper and gold.
Claim 23
Dependent Claim
20 words
The method of claim 18, wherein the substance is solder when it is exposed to the strongly bonded fluorine-containing gas.
Claim 24
Dependent Claim
14 words
The method of claim 19, wherein the substance is solder precoated on a surface.
Claim 25
Dependent Claim
12 words
The method of claim 19, wherein the substance is a solder preform.
Claim 26
Dependent Claim
15 words
The method of claim 18, wherein the substance is a solder in a powder form.
Claim 27
Independent Claim
144 words
A method of improving soldering processes employing flux, comprising: (a) selecting a strongly internally bonded fluorine-containing gas: and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas, wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein said substance is selected from the group consisting of solder precoated on a surface, solder preform, and solder in a powder form which will be incorporated in a solder paste at a future time, and said surface is selected from the group consisting of: (a) solder precoated on a surface, tin, copper, and gold, which have been treated with said strongly internally bonded fluorine-containing gas; and (b) solder precoated on a surface, tin, copper, and gold, which have not been treated with said strongly internally bonded fluorine-containing gas.
Claim 28
Independent Claim
144 words
A method of improving soldering processes employing flux, comprising: (a) selecting a strongly internally bonded fluorine-containing gas: and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas, wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein said substance is selected from the group consisting of solder precoated on a surface, solder preform, and solder in a powder form which will be incorporated in a solder paste at a future time, and said surface is selected from the group consisting of: (a) solder precoated on a surface, tin, copper, and gold, which have been treated with said strongly internally bonded fluorine-containing gas; and (b) solder precoated on a surface, tin, copper, and gold, which have not been treated with said strongly internally bonded fluorine-containing gas.
Claim 29
Independent Claim
120 words
A method of improving soldering processes employing flux, comprising: (a) selecting a strongly internally bonded fluorine-containing gas; and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas, wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein said solder is selected from the group consisting untreated solder precoated on a surface, untreated solder preform, untreated solder in a powder form which has been incorporated in a solder paste, and molten solder, and said surface is selected from the group consisting of solder precoated on a surface, tin, copper and gold, which have been treated with said strongly internally bonded fluorine-containing gas.
Claim 30
Independent Claim
120 words
A method of improving soldering processes employing flux, comprising: (a) selecting a strongly internally bonded fluorine-containing gas; and (b) exposing a substance to be soldered to the strongly internally bonded fluorine-containing gas, wherein said method results in a treatment of said substance which enables solder to be reflowed on a surface at a later time, wherein said solder is selected from the group consisting untreated solder precoated on a surface, untreated solder preform, untreated solder in a powder form which has been incorporated in a solder paste, and molten solder, and said surface is selected from the group consisting of solder precoated on a surface, tin, copper and gold, which have been treated with said strongly internally bonded fluorine-containing gas.
Claim 31
Dependent Claim
15 words
The method of claim 18, wherein the strongly internally bonded fluorine-containing gas is hydrogen fluoride.
Claim 32
Dependent Claim
57 words
The method of claim 25, further comprising obtaining said hydrogen fluoride by a method selected from the group consisting of: (a) utilizing anhydrous HF; (b) evaporation from aqueous HF; (c) utilizing a chemical reaction to form HF; and (d) utilizing electrical discharge to form HF, where the HF is extracted from the discharge in the effluent flow.
Claim 33
Dependent Claim
116 words
The method of claim 26, wherein hydrogen fluoride is obtained by utilizing electrical discharge to form HF in an effluent, said electrical discharge being obtained by a method selected from the group consisting of: (a) glow discharge at low pressure where the discharge is produced by a component selected from the group consisting of: (i) an inductively coupled electrical generator; (ii) a capacitively coupled electrical generator; and (iii) a microwave generator; (b) high pressure discharge where the discharge is produced by a component selected from the group consisting of: (i) a corona discharge electrode; (ii) spark-gap electrodes; (iii) a gas filled plasma coupled electrode; (iv) an inductively coupled electrical generator; and (v) a focussed microwave generator.
Claim 34
Dependent Claim
16 words
The method of claim 18, wherein the method is performed at or near ambient atmospheric pressure.
Claim 35
Dependent Claim
18 words
The method of claim 28, wherein the method is performed at a pressure lower than ambient atmospheric pressure.
Claim 36
Dependent Claim
25 words
The method of claim 18, wherein the method is performed in an evacuated chamber at low pressure in the range where glow discharge can occur.
Claim 37
Dependent Claim
21 words
The method of claim 18, wherein the method is performed at an exposure time of between 0.5 minute and one hour.
Claim 38
Dependent Claim
19 words
The method according to claim 31, wherein the temperature is 80° C. and the exposure time is 1.5 minute.
Claim 39
Dependent Claim
13 words
The method according to claim 18, wherein said substance is tin lead solder.
References Cited (Backward Citations)
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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) | 2000-03-10 | 2000-09-09 | 2001-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-03-10 | 2004-09-09 | 2005-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-03-10 | 2008-09-09 | 2009-03-11 | $7700.00 | Window Closed / Lapsed |