Claims
- 1. A reduced CTE laminate circuitized structure having a specified CTE; comprising:a. resin; b. first and second woven glass mats impregnated with the resin and a curing agent and B-stage cured; c. a conductive metal layer; and d. at least one non-woven quartz or glass mat having a weight per unit area of less than about 34 grams/meters2 and sandwiched between the first and second woven glass mats; wherein the amount of resin, woven glass cloth and metal are determined as a specified volume percent of the reduced CTE structure, and wherein the amount of non-woven quartz or glass mat is determined according to the following formula: VOLF=(CTER)(MODR)(VOLR)+(CTEW)(MODW)(VOLW)+(CTEM)(MODM)(VOLM)(CTECOMP)(MODF)-(CTEF)(MODF)-(CTECOMP)(MODR)(VOLR)-(CTECOMP)(MODW)(VOLW)-(CTECOMP)(MODM)(VOLM)(CTECOMP)(MODF)-(CTEF)(MODF); wherein the values of said formula are CTECOMP=CTE of the circuitized structure, CTER=CTE of the resin, MODR=Modulus of the resin, VOLR=specified volume percent of the resin, CTEW=CTE of the woven glass cloth, MODW=Modulus of the woven glass cloth, VOLW=specified volume percent of the woven glass cloth, CTEM=CTE of the metal, MODM=Modulus of the metal, VOLM=specified volume percent of the metal, CTEF=CTE of the at least one non-woven quartz or non-woven glass mat, MODF=Modulus of the at least one non-woven quartz or non-woven glass mat, and VOLF=specified volume percent of the at least one non-woven quartz or non-woven glass mat.
- 2. The reduced CTE laminate circuitized structure of claim 1 wherein the resin is epoxy resin.
- 3. The reduced CTE laminate circuitized structure of claim 1 wherein the woven cloth is E-glass.
- 4. The reduced CTE laminate circuitized structure of claim 1 wherein the structure has a percent voids of from about 0 to 5% by volume.
- 5. The reduced CTE laminate of claim 1, wherein the non-woven mat is a non-woven quartz mat.
- 6. The reduced CTE laminate of claim 1, wherein the non-woven mat is a non-woven glass mat.
- 7. The reduced CTE laminate of claim 1, wherein the first and second layers of woven glass mats have an extent of full cure and are B-stage cured to an extent of not more than about 40% of full cure.
- 8. The reduced CTE laminate of claim 1, wherein the first and second layer of woven glass mats have an extent of fill cure and are B-stage cured to an extent of not more than about 20% of full curve.
- 9. The reduced CTE laminate of claim 1 wherein the non-woven mat has a weight and comprises randomly oriented fibers held together by a binder, said binder comprising from about 5 to 15% of the non-woven mat weight.
- 10. The reduced CTE laminate of claim 9 wherein the fibers have an average length of from about 0.25 to 3.0 inches.
- 11. The reduced CTE laminate of claim 10 wherein the fibers have an average diameter of from about 5 to 12 microns.
- 12. The reduced CTE laminate of claim 1 wherein the non-woven mat has at least about 50% void space prior to being impregnated with the resin.
REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of a previous application filed in the United States Patent and Trademark Office by Lawrence Robert Blumberg, Robert Maynard Japp, William John Rudik, and John Frank Surowka on Jun. 13, 1997, titled “METHOD FOR REDUCING COEFFICIENT OF THERMAL EXPANSION IN CHIP ATTACH PACKAGES” and assigned Ser. No. 08/874,902 now U.S. Pat. No. 6,136,733.
US Referenced Citations (10)
Foreign Referenced Citations (1)
Number |
Date |
Country |
2224293 |
Oct 1974 |
FR |
Non-Patent Literature Citations (3)
Entry |
IBM Research Disclosure n252 04-85, “Dry Process for Laminating Boards” by Chellis et al, Apr., 1985. |
IBM Technical Disclosure Bulletin 09-84, p. 1964, “Substrate for Surface Solder Devices” by Chellis et al. |
IBM Technical Disclosure Bulletin 04-78, p. 4723, “Prepreg Manufacturing Process” by Haining et al. |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
08/874902 |
Jun 1997 |
US |
Child |
09/693766 |
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US |