Thermal Cycling Apparatus and Method for Providing Thermal Uniformity

Abstract

An apparatus and method for rapid thermal cycling including a thermal diffusivity plate. The thermal diffusivity plate can provide substantial temperature uniformity throughout the thermal block assembly during thermal cycling by a thermoelectric module. An edge heater can provide substantial temperature uniformity throughout the thermal block assembly during thermal cycling.

What is claimed is: 
     
         1 . An apparatus for thermally cycling biological samples comprising:
 a thermal block assembly for receiving said biological samples;   a thermoelectric module coupled to said thermal block assembly; and   a heat sink, wherein said heat sink is coupled to said thermoelectric module with a thermal interface medium, wherein said heat sink comprises a base plate, fins, and a thermal diffusivity plate, and wherein said thermal diffusivity plate comprises a different material than said base plate and fins,   wherein said thermal diffusivity plate provides substantial temperature uniformity to said thermal block assembly during thermal cycling.   
     
     
         2 . The apparatus of  claim 1 , wherein said thermal diffusivity plate is positioned to couple to said thermoelectric module with the thermal interface medium. 
     
     
         3 . The apparatus of  claim 1 , wherein said thermal block assembly comprises at least one of silver, gold, aluminum, silicone carbide, and magnesium. 
     
     
         4 . The apparatus of  claim 1 , wherein said thermoelectric module comprises a thermoelectric gap, wherein said thermoelectric gap provides substantial temperature uniformity throughout said thermal block assembly. 
     
     
         5 . The apparatus of  claim 1 , further comprising an edge heater, wherein said edge heater is coupled to the perimeter of said thermal block assembly. 
     
     
         6 . The apparatus of  claim 1 , wherein said apparatus provides a PCR cycle time of less than thirty seconds. 
     
     
         7 . The apparatus of  claim 1 , wherein said thermoelectric module comprises at least two power regions. 
     
     
         8 . The apparatus of  claim 1 , further comprising a seal positioned on top of said thermal block assembly. 
     
     
         9 . The apparatus of  claim 1 , wherein said thermal diffusivity plate is positioned within said base plate. 
     
     
         10 . The apparatus of  claim 1 , wherein said thermoelectric module's horizontal surface area overlaps said thermal diffusivity plate's horizontal surface area. 
     
     
         11 . The apparatus of  claim 10 , wherein said thermoelectric module's horizontal surface area is larger than said thermal diffusivity plate's horizontal surface area. 
     
     
         12 . The apparatus of  claim 10 , wherein said thermal diffusivity plate's horizontal surface area is larger than said thermoelectric module's horizontal surface area. 
     
     
         13 . An apparatus for thermally cycling biological samples comprising:
 a thermal block assembly for receiving said biological samples;   a thermoelectric module capable of heating and cooling, wherein the thermoelectric module is coupled to said thermal block assembly;   a heat sink; and   a thermal diffusivity plate comprising copper coupled to said thermoelectric module with a thermal interface medium and coupled to said heat sink, wherein said thermal diffusivity plate is positioned between said thermoelectric module and said heat sink and has a significantly greater thermal diffusivity than said heat sink, and provides substantial temperature uniformity to said thermal block assembly during thermal cycling.   
     
     
         14 . The apparatus of  claim 13 , wherein said substantial temperature uniformity provides cooling of at least 10° C. in at most ten seconds for said thermal block assembly. 
     
     
         15 . The apparatus of  claim 13 , wherein said thermoelectric module comprises a thermoelectric gap, wherein said thermoelectric gap provides substantial temperature uniformity throughout said thermal block assembly. 
     
     
         16 . The apparatus of  claim 13 , further comprising an edge heater, wherein said edge heater is coupled to the perimeter of said thermal block assembly. 
     
     
         17 . The apparatus of  claim 13 , wherein said thermoelectric module's horizontal surface area overlaps said thermal diffusivity plate's horizontal surface area. 
     
     
         18 . The apparatus of  claim 17 , wherein said thermoelectric module's horizontal surface area is larger than said thermal diffusivity plate's horizontal surface area. 
     
     
         19 . The apparatus of  claim 17 , wherein said thermal diffusivity plate's horizontal surface area is larger than said thermoelectric module's horizontal surface area. 
     
     
         20 . The apparatus of  claim 13 , wherein said thermal diffusivity plate is positioned within a base plate of said heat sink.