US4951400A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for processing plastic packaged electronic devices
Assignee: Teradata US Inc
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Filing: 1988-12-27
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Granted: 1990-08-28
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Expires: 2008-12-27
Abstract
Abstract The subject invention is a method for processing a plastic packaged electronic device with soldered leads. The solder has a critical temperature which if exceeded more than once results in its oxidation. The method comprises protecting the device with a carrier, and baking the device and carrier in a low pressure environment and at a temperature sufficiently high enough to drive off moisture previously absorbed by the plastic but lower than the critical temperature of the solder.
Inventors
- 👤 Blaine K. Elliott
- 👤 Duane A. Briggs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 05:55
CPC Classifications
H; H10; H10W; H10W74/00; H10W74/01; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/341; H05K2201/00; H05K2201/10; H05K2201/10613; H05K2201/10621; H05K2201/10689; H05K2203/00; H05K2203/11; H05K2203/1105; H05K2203/30; H05K2203/304; Y; Y02; Y02P; Y02P70/00; Y02P70/50
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
32 words
A method for processing an electronic device packaged in plastic comprising: protecting said device with a carrier; and baking said device and carrier to controllably drive off moisture absorbed by said plastic.
Claim 2
Independent Claim
32 words
A method for processing an electronic device packaged in plastic comprising: protecting said device with a carrier; and baking said device and carrier to controllably drive off moisture absorbed by said plastic.
Claim 3
Dependent Claim
25 words
The method of claim 1, wherein said baking step comprises: placing said device and carrier in an oven; depressurized said oven; and heating said device.
Claim 4
Dependent Claim
24 words
The method of claim 2, wherein said step of depressurizing said oven includes reducing the pressure within said oven to less than atmospheric pressure.
Claim 5
Dependent Claim
25 words
The method of claim 3, wherein said step of depressurizing said oven further includes reducing the pressure within said oven at less than 35 torr.
Claim 6
Dependent Claim
26 words
The method of claim 4, wherein said step of heating said device includes raising the temperature within said oven to between 35° C. and 40° C.
Claim 7
Dependent Claim
42 words
The methood of claim 5, wherein said step of depressurizing said oven includes reducing the pressure within said oven to about 30 torr, and wherein said step of heating said device includes raising the temperature within said oven to about 35° C.
Claim 8
Dependent Claim
49 words
The method of claim 2, wherein said carrier has acritical temperature at which its structure degrades, said critical temperature being less than the melting point of said plastic package and wherein said heating step includes heating said device to a temperature less than the critical temperature of said carrier.
Claim 9
Dependent Claim
23 words
The method of claim 7, wherein said carrier indludes a tube and wherein said protecting step comprises inserting said device in said tube.
Claim 10
Dependent Claim
23 words
The method of claim 7, wherein said carrier includes a tape and wherein said protecting step comprises afixing said device to said tape.
Claim 11
Dependent Claim
52 words
The method of claim 7, wherein said plastic package electronic device has leads coated with solder, said solder having a critical temperature which if exceeded more than one results in its oxidation, and wherein said heating step includes heating said device to a temperature less than the critical temperature of said solder.
Claim 12
Independent Claim
67 words
A method for processing an electronic device packaged in plastic having leads coated with solder, said solder having a critical temperature which if exceeded more than once results in its oxidation, said method comprising: baking said device in a low pressure environment and at a temperature sufficiently high enough to drive off moisture previously absorbed by said plastic but lower than the critical temperature of said solder.
Claim 13
Independent Claim
67 words
A method for processing an electronic device packaged in plastic having leads coated with solder, said solder having a critical temperature which if exceeded more than once results in its oxidation, said method comprising: baking said device in a low pressure environment and at a temperature sufficiently high enough to drive off moisture previously absorbed by said plastic but lower than the critical temperature of said solder.
Claim 14
Dependent Claim
13 words
The method of claim 11, wherein said pressure is less than atmospheric pressure.
Claim 15
Dependent Claim
13 words
The method of claim 12, wherein said pressure is less than 35 torr.
Claim 16
Dependent Claim
20 words
The method of claim 13, wherein said baking step includes heating said device to between 35° C. and 40° C.
Claim 17
Dependent Claim
24 words
The method of claim 14, wherein said pressure is about 30 torr, and said baking step includes heating said device to about 35° C.
Claim 18
Independent Claim
74 words
A method for processing a plastic packaged electronic device having leads coated with solder, said solder having a critical temperature which if exceeded more than once results in its oxidation, said method comprising: protecting said device with a carrier; placing said device and carrier in an oven; depressurizing said oven; and heating said device to a temperature less than the critical temperature of said solder to controllably drive off moisture absorbed by said plastic.
Claim 19
Independent Claim
74 words
A method for processing a plastic packaged electronic device having leads coated with solder, said solder having a critical temperature which if exceeded more than once results in its oxidation, said method comprising: protecting said device with a carrier; placing said device and carrier in an oven; depressurizing said oven; and heating said device to a temperature less than the critical temperature of said solder to controllably drive off moisture absorbed by said plastic.
Claim 20
Dependent Claim
50 words
The method of claim 16, wherein said carrier has a critical temperature at which its structure degrades, said critical temperature being less than the melting point of said plastic package and wherein said heating step includes heating said device to a temperature less than the critical temperature of said carrier.
Claim 21
Dependent Claim
24 words
The method of claim 17, wherein said step of depressurizing said oven includes reducing the pressure within said oven to less than atmospheric presure.
Claim 22
Dependent Claim
25 words
The method of claim 18, wherein said step of depressurizing said oven further includes reducing the pressure within said oven to less than 35 torr.
Claim 23
Dependent Claim
25 words
The method of claim 19, wherein said step of heating said device includes raising the temperature within oven to between 35° C. and 40° C.
Claim 24
Dependent Claim
42 words
The method of claim 20, wherein said step of depressurizing said oven includes reducing the pressure within said oven to about 30 torr; and wherein said step of heating said device includes raising the temperature within said oven to about 35° C.
Claim 25
Dependent Claim
23 words
The method of claim 21, wherein said carrier includes a tube and wherein said protecting step comprises inserting said device in said tube.
Claim 26
Dependent Claim
23 words
The method of claim 21, wherein said carrier includes a tape and wherein said protecting step comprises affixing said device to said tape.
Claim 27
Independent Claim
28 words
A method for processing an electronic device packaged in plastic comprising: baking said device at less than atmospheric pressure to drive off moisture previously absorbed by said plastic.
Claim 28
Independent Claim
28 words
A method for processing an electronic device packaged in plastic comprising: baking said device at less than atmospheric pressure to drive off moisture previously absorbed by said plastic.
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) | 1993-08-27 | 1994-02-26 | 1994-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-27 | 1998-02-26 | 1998-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-27 | 2002-02-26 | 2002-08-28 | $7700.00 | Window Closed / Lapsed |