Undoped silicon heat spreader window

Abstract

A system and method for thermal management of a device under test (DUT). In particular, a system is described for performing optical microscopy. The system includes a heat spreader window that consists of substantially undoped silicon. The window is configured to be coupled to a back side of a substrate of a DUT such that thermal energy from the DUT is spread to the heat spreader window. A contact region is coupled to the heat spreader window. The contact region is configured for contact with a solid immersion lens (SIL) optical system for optical examination of the DUT. A heat exchanger is coupled to the heat spreader window for removing the thermal energy from the DUT during its operation, wherein the heat exchanger is configured to allow access to the heat spreader window.

1 . A method of preparing a heat sink for thermal conduction from a device under test (DUT), comprising:
 fabricating a heat spreader window by reducing to size a substrate consisting essentially of substantially undoped silicon, such that the heat spreader is sized to be coupled to a back side of the DUT so that thermal energy from said DUT is spread to said heat spreader window;   lapping said heat spreader window to a desired thickness; and,   polishing said heat spreader window to a desired optical quality.   
     
     
         2 . The method of  claim 1 , further comprising configuring said heat spreader window to be coupled to a heat exchanger that is configured to remove said thermal energy away from said DUT, wherein said heat exchanger is configured to allow access to said heat spreader window. 
     
     
         3 . The method of  claim 1 , wherein said reducing to size comprises:
 cleaving a semiconductor wafer of substantially undoped silicon to said size of said heat spreader window.   
     
     
         4 . The method of  claim 1 , wherein said lapping said heat spreader window comprises:
 grinding a surface of said heat spreader window to said desired thickness.   
     
     
         5 . The method of  claim 1 , wherein said polishing said heat spreader window comprises:
 polishing at least one surface of said heat spreader window to said desired optical quality.   
     
     
         6 . The method of  claim 2 , wherein said configuring said heat spread window to be coupled to a heat exchanger further comprises:
 coupling a thermally conductive plating around said heat spreader window to facilitate removal of said thermal energy from said heat spreader window to said heat exchanger when said heat exchanger is coupled to said heat spreader window.   
     
     
         7 . The method of  claim 1 , further comprising:
 providing an anti-reflective coating (ARC) onto said heat spreader window.   
     
     
         8 . The method of  claim 1 , wherein the thickness of said heat spreader window is approximately 300 micrometers. 
     
     
         9 . A method of thermal conduction, comprising:
 coupling a heat spreader window consisting essentially of substantially undoped silicon to a heat exchanger, wherein said heat exchanger is configured to allow optical access to said heat spreader window;   coupling said heat spreader window to a back side of a substrate of a device under test (DUT);   coupling an optical sensor system to the heat exchanger; and   receiving energy from said DUT during its operation by the optical sensor system through the optical access in the heat exchanger.   
     
     
         10 . The method of  claim 9 , wherein said coupling an optical sensor system to the heat exchanger comprises:
 bringing into contact a solid immersion lens (SIL) of said optical sensor system with said heat spreader window.   
     
     
         11 . The method of  claim 9 , wherein said coupling an optical sensor system to the heat exchanger comprises:
 configuring an air coupled optical lens of said optical sensor system to receive said energy.   
     
     
         12 . The method of  claim 9 , further comprising:
 configuring said heat spreader window such that a first index of refraction of said heat spreader window is substantially similar to a second index of refraction of said substrate.   
     
     
         13 . The method of  claim 10 , further comprising:
 configuring said heat spreader window such that said first index of refraction of said heat spreader window is substantially similar to a third index of refraction of a solid immersion lens (SIL) of said optical sensor system.   
     
     
         14 . The method of  claim 9 , wherein said coupling a heat spreader window comprises:
 coupling a thermally conductive plating around said heat spreader window; and   coupling said heat conductive plating to said heat exchanger to facilitate removal of said thermal energy from said heat spreader window to said heat exchanger.   
     
     
         15 . The method of  claim 14 , further comprising coupling a spray cooling system to said heat spreader window. 
     
     
         16 . The method of  claim 1 , further comprising:
 providing an anti-reflective coating (ARC) onto said heat spreader window.   
     
     
         17 . A method for performing optical microscopy on a device under test (DUT), comprising:
 coupling a heat spreader window consisting essentially of substantially undoped silicon to a back side of a substrate of said DUT, such that thermal energy from said DUT is spread to said heat spreader window;   contacting a solid immersion lens (SIL) optical system to said heat spreader window for optical examination of said DUT; and   coupling a heat exchanger coupled to said heat spreader window for removing said thermal energy from said DUT during its operation, wherein said heat exchanger is configured to allow optical access to said heat spreader window by said optical system.   
     
     
         18 . The method of  claim 17 , further comprising:
 coupling a heat conductive plate to said heat spreader window for coupling said heat spreader window to said heat exchanger.   
     
     
         19 . The system of  claim 17 , further comprising:
 providing an anti-reflective coating (ARC) onto said heat spreader window.   
     
     
         20 . The system of  claim 1 , further comprising coupling a spray cooling system to said heat spreader window.