Stress-resistant circuit board
AssigneeW. L. Gore & Associates, Inc.
InventorsC. Thomas Rosenmayer, Paul Fischer
Life of this patent
Estimating the term…
Abstract
A circuit board resists shear stress caused by the unequal thermal coefficients of expansion of a mounted electronic component and a circuit board upon which it is mounted. The circuit board is defined by a support layer, a shear stress-relieving layer and a conductive layer. The shear stress-relieving layer comprises a layer of expanded polytetrafluoroethylene having a compressive modulus of less than 50,000 pounds per square inch.
Claims8
A circuit board having first and second surfaces, the circuit board mounting at least one electronic component on a predetermined circuit board surface, the circuit board comprising:
- a support layer having a top and a bottom surface;
- means for absorbing shear stress caused by unequal thermal coefficients of expansion between the at least one electronic component and the circuit board, the shear stress absorbing means comprising a layer of expanded polytetrafluroethylene having a compressive modulus of less than 50,000 PSI, the layer of expanded polytetrafluroethylene being completely bonded to the top surface of the support layer;
- bonding medium for completely bonding the shear stress absorbing means to the support layer;
- a conductive layer bonded to the shear stress absorbing means;
- and
- at least one electronic component electrically connected to the conductive layer.
A circuit board which resists shear stress caused by thermal expansion, the circuit board having first and second surfaces and comprising:
- a support layer having a top and a bottom surface;
- a layer of expanded polytetrafluoroethylene having a compressive modulus of less than 50,000 PSI, the layer of expanded polytetrafluroethylene having a thickness from about 0.002 to 0.025 inches and being completely bonded to the top surface of the support layer;
- a conductive layer bonded to the layer of expanded polytetrafluroethylene;
- and
- at least one electronic component electrically connected to the conductive layer.
A circuit board comprising:
- a support layer having a top and a bottom surface;
- a layer of expanded polytetrafluoroethylene having a compressive modulus of less than 50,000 PSI, the layer of expanded polytetrafluroethylene having a thickness from about 0.002 to 0.025 inches and being completely adhesively bonded to the top surface of the support layer;
- a conductive layer bonded to the layer of expanded polytetrafluroethylene means;
- and
- at least one conductively plated aperture formed completely through the circuit board to provide electrical contact between the first and second circuit board surfaces.
A circuit board which resists strain caused by thermal expansion, the circuit board having first and second surfaces and comprising:
- a support layer having a top and a bottom surface;
- a layer of expanded polytetrafluoroethylene having a compressive modulus of less than 50,000 PSI, the layer of expanded polytetrafluroethylene having a thickness from about 0.002 to 0.025 inches and being completely adhesively bonded to the top surface of the support layer;
- and
- a conductive layer bonded to the layer of expanded polytetrafluroethylene.
Dependencies are inferred from the claim text.