US4975312A
Expired / Lapsed
US
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Multiaxially oriented thermotropic polymer substrate for printed wire board
Assignee: Vencore Services and Solutions Inc
•
Filing: 1988-06-20
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Granted: 1990-12-04
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Expires: 2008-06-20
Abstract
Abstract The present invention is directed to the use of multiaxially oriented (e.g., biaxially) thermotropic polymers as a substrate material for the preparation of printed wire boards (PWB). In preferred embodiments, the PWB of the present invention comprises a generic, high density, organic multilayer PWB comprising XYDAR® and/or VECTRA® films, capable of being employed as a high density leadless perimeter and in grid array ceramic chip packages.
Inventors
- 👤 Richard W. Lusignea
- 👤 James L. Racich
- 👤 Andrew C. Harvey
- 👤 Ruby R. Chandy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:18
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B38/00; B32B38/0008; H; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/0313; B32B2255/00; B32B2255/10; B32B2255/20; B32B2255/205; B32B2307/00; B32B2307/50; B32B2307/514; B32B2307/542; B32B2307/546; B32B2307/70; B32B2307/724; B32B2307/7242; B32B2307/7246; B32B2310/00; B32B2310/14; B32B2311/00; B32B2311/12; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24917; Y10T428/26; Y10T428/266; Y10T428/31504; Y10T428/31533
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
44 words
As an article of manufacture, a printed wire board substrate prepared from a multiaxially oriented thermotropic liquid crystalline polymer film having a tailored coefficient of thermal expansion in the X-Y direction wherein the thickness of the film is not more than about 0.004 in.
Claim 2
Dependent Claim
44 words
As an article of manufacture, a printed wire board substrate prepared from a multiaxially oriented thermotropic liquid crystalline polymer film having a tailored coefficient of thermal expansion in the X-Y direction wherein the thickness of the film is not more than about 0.004 in.
Claim 3
Dependent Claim
23 words
The printed wire board substrate of claim 1, which further has the following characteristics: (a) is non-electrically conducting; and (b) has low-moisture absorption.
Claim 4
Dependent Claim
19 words
The printed wire board substrate of claim 2, wherein the moleculally oriented polymer is selected from XYDAR® or VECTRA®.
Claim 5
Dependent Claim
16 words
The printed wire board substrate of claim 3, which further comprises a copper layer bonded thereto.
Claim 6
Dependent Claim
32 words
The printed wire board substrate of claim 3, which has the following additional property: tailorable coefficient of thermal expansion (CTE) (X-Y direction) in range of from about 3 to 7×10 -6 in./in./°C.
Claim 7
Dependent Claim
23 words
The printed wire board substrate of claim 4, which has the following additional property: CTE of thickness (Z direction) approaching that of copper.
Claim 8
Dependent Claim
24 words
The printed wire board substrate of claim 3, which has the following additional property: low-moisture absorption, i.e., not exceeding about 0.5 percent at saturation.
Claim 9
Dependent Claim
28 words
The printed wire board substrate of claim 3, which further comprises a plurality of layers of molecularly oriented thermotropic liquid crystalline film, making up a multilayer laminated board.
Claim 10
Dependent Claim
16 words
The printed wire board substrate of claim 8, which further comprises a copper layer bonded thereto.
Claim 11
Dependent Claim
25 words
The printed wire board substrate of claim 8, which has the following additional property: maximum thickness of a single layer not exceeding about 0.0025 in.
Claim 12
Dependent Claim
25 words
The printed wire board substrate of claim 8, which has the following additional property: interlaminar shear strength greater than glass/Kerimid 601 or equal to glass/epoxy.
Claim 13
Dependent Claim
20 words
The printed wire board substrate of claim 8, which has the following additional property: flexural strength equivalent to glass/ polyimide.
Claim 14
Dependent Claim
31 words
The printed wire board substrate of claim 8, which has the following additional property: dielectric constant not exceeding about 3.5 over the functional frequency range of 1 kHz to 500 MHz.
Claim 15
Dependent Claim
27 words
The printed wire board substrate of claim 8, which is capable of being employed as a high density substrate for leadless perimeter and grid array chip packages.
Claim 16
Dependent Claim
41 words
The printed wire board substrate of claim 14, wherein the chip package density requirements include 0.020-in. centers with up to 300 input/outputs (I/Os) for perimeter type packages and 0.050-in. center grid array type packages with up to 240 I/Os per device.
Claim 17
Dependent Claim
19 words
The copper coated PWB substrate of claim 4, wherein the copper has been deposited by means of plasma coating.
Claim 18
Dependent Claim
19 words
The copper coated PWB substrate of claim 4, wherein the copper has been deposited by means of ion plating.
Claim 19
Dependent Claim
19 words
The copper coated PWB substrate of claim 9, wherein the copper has been deposited by means of plasma coating.
Claim 20
Dependent Claim
19 words
The copper coated PWB substrate of claim 9, wherein the copper has been deposited by means of ion plating.
Claim 21
Independent Claim
53 words
A method of forming a multilayer PWB substrate, comprising bonding together several layers of multiaxially oriented Xydar and/or Vectra film, the film having a tailored coefficient of thermal expansion, none of which layers exceeds about 0.0025 inches in thickness, thereby forming a multilayer board having a plurality of laminated multiaxially oriented film layers.
Claim 22
Independent Claim
53 words
A method of forming a multilayer PWB substrate, comprising bonding together several layers of multiaxially oriented Xydar and/or Vectra film, the film having a tailored coefficient of thermal expansion, none of which layers exceeds about 0.0025 inches in thickness, thereby forming a multilayer board having a plurality of laminated multiaxially oriented film layers.
Claim 23
Dependent Claim
12 words
The article of claim 1, wherein the multiaxial orientation is balanced biaxial.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-03 | 1994-06-04 | 1994-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-03 | 1998-06-04 | 1998-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-03 | 2002-06-04 | 2002-12-04 | $7700.00 | Window Closed / Lapsed |