Heat spreader with flexibly supported heat pipe

Abstract

A heat spreader for dissipating heat generated by at least one heat-generating power semiconductor device which, apart from an improved heat coupling between a chip and a heat sink, also comprise a flexible coupling assembly which can compensate for tolerances in the components and in the assembling process. The heat spreader has a base plate ( 11 ) which is connectable in a heat-conducting manner to the at least one power semiconductor device ( 2 ). The base plate ( 11 ) has at least one recess ( 12 ) in which at least one heat pipe ( 13 ) is arranged for dissipating the generated heat, and wherein the at least one heat pipe ( 13 ) is movably supported in the recess ( 12 ).

1 . A heat spreader for dissipating heat generated by at least one heat-generating power semiconductor device ( 2 ), the heat spreader ( 3 ) comprising
 a base plate ( 11 ) which is connectable in a heat-conducting manner to the at least one power semiconductor device ( 2 ),   wherein the base plate ( 11 ) has at least one recess ( 12 ) in which at least one heat pipe ( 13 ) is arranged for dissipating the generated heat, and wherein the at least one heat pipe ( 13 ) is movably supported in the recess ( 12 ).   
     
     
         2 . The heat spreader according to  claim 1 , further comprising at least one heat coupling element ( 4 ) which is connected in a heat-conducting manner to the at least one power semiconductor device ( 2 ) on the one hand and to the heat pipe ( 13 ) on the other hand. 
     
     
         3 . The heat spreader according to  claim 2 , wherein a contact pressure of the heat coupling element ( 4 ) on the heat pipe ( 13 ) and/or on the power semiconductor device ( 2 ) is adjustable via at least one spring element ( 14 ). 
     
     
         4 . The heat spreader according to  claim 3 , wherein the spring element ( 14 ) includes a spiral spring having a defined spring constant, which resiliently supports the heat coupling element ( 4 ) relative to the base plate ( 11 ). 
     
     
         5 . The heat spreader according to  claim 2 , wherein the heat coupling element ( 4 ) is made from copper, aluminum or magnesium. 
     
     
         6 . The heat spreader according to  claim 1 , wherein the heat pipe ( 13 ) has a flattened cross-section. 
     
     
         7 . The heat spreader according to  claim 6 , wherein the cross section of the heat pipe ( 13 ) is dimensioned such that the heat pipe ( 13 ) has a thickness smaller than or equal to a thickness of the base plate. 
     
     
         8 . The heat spreader according to  claim 1 , wherein the recess ( 12 ) is formed at least in part by an opening extending through the base plate ( 11 ). 
     
     
         9 . The heat spreader according to  claim 1 , wherein the recess ( 12 ) is formed at least in part by a groove in the base plate ( 11 ), so that the heat pipe ( 13 ) is in heat-conducting communication with a wall of the base plate. 
     
     
         10 . The heat spreader according to  claim 1 , wherein the recess ( 12 ) is formed by milling, die casting or eroding. 
     
     
         11 . The heat spreader according to  claim 1 , wherein the base plate ( 11 ) is made of a metal. 
     
     
         12 . The heat spreader according to  claim 1 , wherein the at least one heat pipe ( 13 ) is made of metal. 
     
     
         13 . The heat spreader according to  claim 1 , wherein the base plate ( 11 ), the heat pipe ( 13 ) and/or the heat coupling element ( 4 ) is/are provided with a surface coating. 
     
     
         14 . The heat spreader according to  claim 1 , wherein a heat-conducting interlayer is provided for coupling the at least one power semiconductor device ( 2 ) to the heat spreader ( 3 ). 
     
     
         15 . The heat spreader according to  claim 14 , wherein the interlayer comprises a latent-heat storage material ( 15 ). 
     
     
         16 . The heat spreader according to  claim 14 , wherein the interlayer is mechanically secured on the heat coupling element ( 4 ). 
     
     
         17 . The heat spreader according to  claim 1 , wherein the base plate ( 11 ) is connectable to a heat sink ( 8 ) or a heat-releasing surface structure.