Thermal management of printed circuit board components

Abstract

A first thermal management approach involves an air flow through cooling mechanism with multiple airflow channels for dissipating heat generated in a PCA. The air flow direction through at least one of the channels is different from the air flow direction through at least another of the channels. Alternatively or additionally, the airflow inlet of at least one channel is off-axis with respect to the airflow outlet. A second thermal management approach involves the fabrication of a PCB with enhanced durability by mitigating via cracking or PTH fatigue. At least one PCB layer is composed of a base material formed from a 3D woven fiberglass fabric, and conductive material deposited onto the base material surface. A conductive PTH extends through the base material of multiple PCB layers, where the CTE of the base material along the z-axis direction substantially matches the CTE of the conductive material along the x-axis direction.

What is claimed is: 
     
         1 - 10 . (canceled) 
     
     
         11 . A printed circuit board (PCB) with enhanced durability, said PCB comprising a plurality of PCB layers, wherein at least one of said PCB layers comprises:
 a base material formed from a three-dimensional (3D) woven fiberglass fabric impregnated with a resin, said 3D woven fiberglass fabric comprising:   a first group of fibers arranged in a plurality of parallel layers, where each layer comprises a plurality of fibers extending along at least a first (x-axis) direction and aligned in a first (x-y) plane, and where said parallel layers are arranged along a second (z-axis) direction that is orthogonal to said first (x-y) plane; and   a second group of fibers extending along at least said second (z-axis) direction, said second group of fibers being interlaced with said first group of fibers;   a layer of conductive material deposited onto a surface of said base material; and   at least one conductive plated through hole (PTH) extending through said base material of a plurality of said PCB layers, wherein the coefficient of thermal expansion (CTE) of said base material along said second (z-axis) direction substantially matches the CTE of said conductive material along said first (x-axis) direction.   
     
     
         12 . The PCB of  claim 11 , wherein said second group of fibers are interlaced with said first group of fibers in a non-orthogonal weaving pattern. 
     
     
         13 . The PCB of  claim 12 , wherein said non-orthogonal weaving pattern is selected from the list consisting of:
 an angle interlock weaving pattern; and   a multilayer weaving pattern.   
     
     
         14 . The PCB of  claim 11 , wherein said second group of fibers extend along a direction that is at a non-perpendicular angle with respect to said second (z-axis) direction. 
     
     
         15 . The PCB of  claim 11 , wherein the geometry of at least one of: said first group of fibers; and said second group of fibers, is selected from the list consisting of:
 a solid geometry;   a hollow geometry;   a shell geometry; and   a nodal geometry.   
     
     
         16 . The PCB of  claim 11 , wherein said 3D woven fiberglass fabric is selected from the list consisting of:
 E-glass fibers; and   FR-4 fiberglass.   
     
     
         17 . The PCB of  claim 11 , wherein said PTH is copper-plated. 
     
     
         18 . A method for fabricating a PCB with enhanced durability, the method comprising the procedures of:
 forming a base material for at least one PCB layer from a three-dimensional (3D) woven fiberglass fabric, said 3D woven fiberglass fabric comprising:   a first group of fibers arranged in a plurality of parallel layers, where each layer comprises a plurality of fibers extending along a first (x-axis) direction and aligned in a first (x-y) plane, and where said parallel layers extend along a second (z-axis) direction that is orthogonal to said first (x-y) plane; and   a second group of fibers extending along at least said second (z-axis) direction, said second group of fibers being interlaced with said first group of fibers;   impregnated said base material with a resin;   depositing a layer of conductive material onto a surface of said base material; and   forming at least one conductive plated through hole (PTH) extending through said base material of a plurality of layers of said PCB, wherein the coefficient of thermal expansion (CTE) of said base material along said second (z-axis) direction substantially matches the CTE of said conductive material along said first (x-axis) direction.   
     
     
         19 . The method of  claim 18 , wherein said second group of fibers are interlaced with said first group of fibers in a non-orthogonal weaving pattern. 
     
     
         20 . The method of  claim 19 , wherein said non-orthogonal weaving pattern is selected from the list consisting of:
 an angle interlock weaving pattern; and   a multilayer weaving pattern.