US3876460A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fine-line thick-film substrate fabrication
Assignee: FRENCHTOWN AMERICAN Corp A CORP OF NJ
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Filing: 1974-01-24
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Granted: 1975-04-08
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Expires: 1994-01-24
Abstract
Abstract Ceramic substrates having screened and plated conductive lines 3 mils wide with 3 mil spacing are reliably produced by screening onto calcined but not sintered substrates, allowance being made for subsequent shrinkage on sintering to the fully cured state. In addition to better line definition, the process is simpler and more economic than methods currently employed.
Inventors
- 👤 William M Flock
- 👤 Lawrence F Cochran
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 00:23
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/10; H05K3/12; H05K3/1283; H05K3/1291; C; C04; C04B; C04B41/00; C04B41/009; C04B41/45; C04B41/50; C04B41/51; C04B41/80; C04B41/81; C04B41/85; C04B41/88; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; H05K1/09; H05K1/092; H05K2203/00; H05K2203/11; H05K2203/1126; H05K2203/14; H05K2203/1476; H05K3/1216
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
102 words
A METHOD FOR PRODUCING METALLIZED PATTERNS ON CERAMIC BODIES COMPRISING: FORMING AN UNFIRED CERAMIC BODY IN A DESIRED SHAPE, SAID SHAPE TAKING INTO ACCOUNT SHRINKAGE THAT WILL OCCUR ON FIRING; CALCINING SAID BODY AT AN ELEVATED TEMPERATURE SUFFICIENT TO FORM A MONOLITHIC BUT POROUS BODY, SAID CALCINING BEING INSUFFICIENT TO CAUSE ANY SIGNIFICANT SHRINKAGE; APPLYING A METALLIZED COATING IN A DESIRED PATTERN ON SAID CALCINED BODY, SAID PATTERN TAKING INTO ACCOUNT SHRINKAGE THAT WILL OCCUR ON FIRING; AND FIRING SAID BODY AT AN ELEVATED TEMPERATURE SUFFICIENT TO FULLY CURE AND DENSIFY SAID BODY, SAID FIRING BEING CARRIED OUT IN A REDUCING ATMOSPHERE.
Claim 2
Independent Claim
102 words
A METHOD FOR PRODUCING METALLIZED PATTERNS ON CERAMIC BODIES COMPRISING: FORMING AN UNFIRED CERAMIC BODY IN A DESIRED SHAPE, SAID SHAPE TAKING INTO ACCOUNT SHRINKAGE THAT WILL OCCUR ON FIRING; CALCINING SAID BODY AT AN ELEVATED TEMPERATURE SUFFICIENT TO FORM A MONOLITHIC BUT POROUS BODY, SAID CALCINING BEING INSUFFICIENT TO CAUSE ANY SIGNIFICANT SHRINKAGE; APPLYING A METALLIZED COATING IN A DESIRED PATTERN ON SAID CALCINED BODY, SAID PATTERN TAKING INTO ACCOUNT SHRINKAGE THAT WILL OCCUR ON FIRING; AND FIRING SAID BODY AT AN ELEVATED TEMPERATURE SUFFICIENT TO FULLY CURE AND DENSIFY SAID BODY, SAID FIRING BEING CARRIED OUT IN A REDUCING ATMOSPHERE.
Claim 3
Dependent Claim
27 words
The method as claimed in claim 1, wherein said unfired ceramic body is a pressed compact of a high alumina material, formed about 16 to 22% larger
Claim 4
Dependent Claim
24 words
The method as claimed in claim 2, wherein said calcining is carried out at a temperature in the range of 850.degree. to 1200.degree.C., and
Claim 5
Dependent Claim
12 words
The method as claimed in claim 1, wherein said metallized pattern is
Claim 6
Dependent Claim
24 words
The method as claimed in claim 1, and additionally comprising applying a dielectric coating over at least portions of said body and said metallized
Claim 7
Dependent Claim
23 words
The method as claimed in claim 5, wherein said dielectric coating is screen printed, and produces a coating of similar composition to said
Claim 8
Dependent Claim
14 words
The method as claimed in claim 1, wherein said firing is carried out at
Claim 9
Dependent Claim
24 words
The method as claimed in claim 1, and additionally comprising plating a metal onto at least portions of said metallized coating after said firing.
Claim 10
Dependent Claim
24 words
The method as claimed in claim 5, and additionally comprising plating a metal onto portions of said pattern not covered by said dielectric coating
Claim 11
Independent Claim
127 words
A method for producing patterns on thick film ceramic substrates as fine as three mils wide with three mil spacing comprising: forming an unfired ceramic substrate in a desired size and shape, said size taking into account shrinkage that will occur on firing; calcining said substrate at an elevated temperature sufficient to form a monolithic but porous body, said calcining being of insufficient intensity to cause any significant shrinkage; screen printing a metallizing paste in a desired pattern on said substrate, said pattern including lines and spaces proportionally larger than desired final size to take into account shrinkage that will occur on firing; and firing said substrate at an elevated temperature sufficient to fully cure and densify said substrate, said firing being carried out in a reducing
Claim 12
Independent Claim
127 words
A method for producing patterns on thick film ceramic substrates as fine as three mils wide with three mil spacing comprising: forming an unfired ceramic substrate in a desired size and shape, said size taking into account shrinkage that will occur on firing; calcining said substrate at an elevated temperature sufficient to form a monolithic but porous body, said calcining being of insufficient intensity to cause any significant shrinkage; screen printing a metallizing paste in a desired pattern on said substrate, said pattern including lines and spaces proportionally larger than desired final size to take into account shrinkage that will occur on firing; and firing said substrate at an elevated temperature sufficient to fully cure and densify said substrate, said firing being carried out in a reducing
Claim 13
Dependent Claim
24 words
The method as claimed in claim 10, wherein said unfired ceramic substrate is a pressed compact of a high alumina material, formed about 16
Claim 14
Dependent Claim
38 words
The method as claimed in claim 11, wherein said calcining is carried out at a temperature in the range of 850.degree. to 1200.degree.C. for at least one hour, and shrinkage during said calcining is no more than 1%.
Claim 15
Dependent Claim
46 words
The method as claimed in claim 10, and additionally comprising screen printing a dielectric coating over at least portions of said substrate and said pattern prior to said firing, said dielectric coating being adapted to provide a layer of similar composition to said substrate after firing.
Claim 16
Dependent Claim
25 words
The method as claimed in claim 10, wherein said firing is carried out at a temperature in the range of 1400.degree. to 1700.degree.C. for at
Claim 17
Dependent Claim
23 words
The method as claimed in claim 10, and additionally comprising plating a metal onto at least portions of said metallized pattern after said
Claim 18
Dependent Claim
27 words
The method as claimed in claim 13, and additionally comprising plating a metal onto portions of said pattern not covered by said dielectric coating after said firing.
References Cited (Backward Citations)
US3497384A
Cited
US3661635A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-07 | 1978-10-07 | 1979-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-07 | 1982-10-07 | 1983-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-07 | 1986-10-07 | 1987-04-08 | $7700.00 | Window Closed / Lapsed |