Heat conduction for chip stacks and 3-d circuits

Abstract

A semiconductor device assembly and method can include a single semiconductor layer or stacked semiconductor layers, for example semiconductor wafers or wafer sections (semiconductor dice). On each semiconductor layer, a diamond layer formed therethrough can aid in the routing and dissipation of heat. The diamond layer can include a first portion on the back of the semiconductor layer, and one or more second portions which extend vertically into the semiconductor layer, for example completely through the semiconductor layer. Thermal contact can then be made to the diamond layer to conduct heat away from the one or more semiconductor layers. A conductive via can be formed through the diamond layers to provide signal routing and heat dissipation capabilities.

1 . A semiconductor assembly, comprising;
 a semiconductor layer comprising a front side, a back side, and an opening therethrough extending from the back side to the front side; and   a diamond layer extending through the opening and comprising a first surface at the front side of the semiconductor layer and a second surface at the back side of the semiconductor layer.   
     
     
         2 . The semiconductor assembly of  claim 1 , wherein:
 the diamond layer provides an electrical connector; or   the diamond layer provides a nonconductive heat sink.   
     
     
         3 . The semiconductor assembly of  claim 1  wherein the diamond layer comprises:
 a first portion extending through the opening; and 
 a second portion covering the back side of the semiconductor layer. 
 
     
     
         4 . The semiconductor assembly of  claim 1  wherein the semiconductor layer is a first semiconductor layer, and the semiconductor assembly further comprises:
 a second semiconductor layer attached to the front side of the first semiconductor layer, wherein the second semiconductor layer comprises: 
 a back side, a front side, and an opening extending from the back side of the second semiconductor layer to the front side of the second semiconductor layer; 
 a diamond layer extending through the opening in the second semiconductor layer and comprising a first exposed surface at the front side of the second semiconductor layer and a second surface at the back side of the second semiconductor layer; and 
 a thermally conductive connection to the diamond layer, wherein the thermally conductive connection is adapted to conduct heat away from the first and second semiconductor layers during operation of the semiconductor assembly. 
 
     
     
         5 . The semiconductor assembly of  claim 1 , further comprising:
 the diamond layer is an electrical insulator; and   a conductive via within the diamond layer and contacting the diamond layer, wherein the conductive via is electrically isolated from the semiconductor layer by the diamond layer.   
     
     
         6 . The semiconductor assembly of  claim 5 , further comprising:
 at least a portion of the conductive via is directly interposed between portions of the semiconductor layer; and   at least a portion of the diamond layer is directly interposed between portions of the semiconductor layer.   
     
     
         7 . The semiconductor assembly of  claim 1 , further comprising:
 the diamond layer is an electrical conductor and comprises an opening therein; and   a conductive via within the opening in the diamond layer and contacting the diamond layer, wherein the conductive via is electrically connected to the semiconductor layer through the diamond layer.   
     
     
         8 . The semiconductor assembly of  claim 1 , further comprising:
 the diamond layer is an electrical conductor and comprises an opening therein;   a dielectric liner which lines the opening in the diamond layer; and   a conductive via within the opening in the diamond layer, wherein the dielectric liner electrically isolates the conductive via from the diamond layer.   
     
     
         9 . The semiconductor assembly of  claim 1 , further comprising:
 the diamond layer is an electrical insulator;   an electrically conductive layer attached to the diamond layer, wherein the electrically conductive layer is adapted to conduct heat to or away from the diamond layer, and is not adapted to conduct an electrical signal during operation of the semiconductor assembly.   
     
     
         10 . The semiconductor assembly of  claim 1 , wherein the diamond layer extending through the opening is electrically conductive. 
     
     
         11 . The semiconductor assembly of  claim 1 , wherein the diamond layer extending through the opening is an electrical insulator. 
     
     
         12 . The semiconductor assembly of  claim 1  wherein the opening is a first opening and the semiconductor assembly further comprises:
 the semiconductor layer further comprises a second opening therethrough extending from the back side to the front side; and 
 a conductive layer which fills the second opening in the semiconductor layer. 
 
     
     
         13 . The semiconductor assembly of  claim 12 , wherein the diamond layer is an electrically conductive diamond layer. 
     
     
         14 . The semiconductor assembly of  claim 12 , further comprising a p-type dopant within the diamond layer at a concentration sufficient to result in an electrically conductive diamond layer. 
     
     
         15 . The semiconductor assembly of  claim 12 , wherein the diamond layer is an electrical insulator. 
     
     
         16 . A semiconductor assembly, comprising:
 a semiconductor layer having a front side, a back side, and an opening therethrough extending from the back side to the front side;   a first portion of a diamond layer extending through the opening and comprising a first surface at the front side of the semiconductor layer and a second surface at the back side of the semiconductor layer;   a second portion of a diamond layer covering the back side of the semiconductor layer;   an opening extending through both the first portion of the diamond layer and the second portion of the diamond layer; and   a conductor that fills the opening extending through both the first portion of the diamond layer and the second portion of the diamond layer to provide a conductive path extending between the front side of the semiconductor layer and the back side of the semiconductor layer.   
     
     
         17 . The semiconductor assembly of  claim 16 , further comprising:
 the conductor that fills the opening provides a conductive path extending between a front surface of the first portion of the diamond layer and a back surface of the second portion of the diamond layer.   
     
     
         18 . The semiconductor assembly of  claim 17 , further comprising:
 the first portion of the diamond layer is an electrical insulator; and   the conductor that fills the opening is electrically isolated from the semiconductor layer by the first portion of the diamond layer.   
     
     
         19 - 25 . (canceled) 
     
     
         26 . A semiconductor assembly, comprising:
 a semiconductor layer comprising a front side, a back side, and an opening therethrough extending from the back side to the front side, the opening defining a perimeter of an isolated portion of the semiconductor layer;   a diamond layer on the back side of the semiconductor layer; and   a diamond portion extending through the opening.   
     
     
         27 . The semiconductor assembly of  claim 26 , wherein the diamond portion is electrically insulating thereby electrically isolating the isolated portion of the semiconductor layer from other portions of the semiconductor layer. 
     
     
         28 . The semiconductor assembly of  claim 26 , one or more conductive through substrate vias extending through the isolated portion of the semiconductor layer and the diamond layer.