초록 ▼

A heat spreader having at least two adjoining layers each having at least two pyrolytic graphite strips cut from a sheet of pyrolytic graphite along the z direction. Thermal conductivity in the xy plane of the graphite sheet is greater than in the z direction. The z direction cut provides strips whi

A heat spreader having at least two adjoining layers each having at least two pyrolytic graphite strips cut from a sheet of pyrolytic graphite along the z direction. Thermal conductivity in the xy plane of the graphite sheet is greater than in the z direction. The z direction cut provides strips which are each oriented 90 degrees such that the thickness direction of the original sheet becomes the width or length of the cut strip. A side of a first strip adjoins a side of a second strip in each layer. Because of the greater thermal conductivity in the xy plane of the strips as compared to the z direction heat transfers more rapidly in the length and thickness direction of the strips than across adjoining sides of the oriented strips in each layer. The first layer strips are oriented about 90 degrees from the orientation of the second layer strips.

대표청구항 ▼

We claim: 1. A heat spreader comprising:a) a first planar element of pyrolytic graphite having a relatively high thermal conductivity in a direction of a first lateral dimension of a first plane of the first planar element and in a thickness direction of the first planar element and having a relativ

We claim: 1. A heat spreader comprising:a) a first planar element of pyrolytic graphite having a relatively high thermal conductivity in a direction of a first lateral dimension of a first plane of the first planar element and in a thickness direction of the first planar element and having a relatively low thermal conductivity in a direction of second lateral dimension of the first planar element, the first planar element having a first side which extends in a direction out of the first plane of the first planar element and a second side which extends in the direction of relatively high thermal conductivity of the first planar element,b) a second planar element of pyrolytic graphite having a relatively high thermal conductivity in a direction of a first lateral dimension of a second plane of the second planar element and in a thickness direction of the second planar element and having a relatively low thermal conductivity in a direction of a second lateral dimension of the second planar element, the second planar element having a third side which extends in a direction out of the second plane of the second planar element and a fourth side which extends in the direction of relatively high thermal conductivity of the second planar element,wherein at least a portion of the first side of the first planar element which extends in a direction out of the first plane of the first planar element adjoins at least a portion of the third side of the second planar element which extends in a direction out of the second plane of the second planar element, andc) a third planar element of pyrolytic graphite having a relatively high thermal conductivity in a direction of a first lateral dimension of a third plane of the third planar element and in a thickness direction of the third planar element and having a relatively low thermal conductivity in a direction of a second lateral dimension of the third planar element, the third planar element having a fifth side which extends in the direction of relatively high thermal conductivity of the third planar element, the fifth side of the third planar element adjoining the second side of the first planar element and the fourth side of the second planar element, and the orientation of the direction of relatively low thermal conductivity of the first planar element and second planar element is at a different angle with respect to the direction of relatively low thermal conductivity of the third planar element.