Microelectronic refrigeration system and method

Abstract

A microelectronic refrigeration system is provided for cooling an electronic device. The microelectronic refrigeration system is configured to contain a refrigerant, a low concentration solution, and an intermediary gas. The microelectronic refrigeration system includes: (i) an evaporator configured to be thermally coupled to the electronic device, to receive and vaporize the refrigerant, and to receive the intermediary gas; and (ii) an absorber fluidly coupled to the evaporator. The absorber is configured to receive the low concentration solution and the vaporized refrigerant, which dissolves in the low concentration solution to produce a high concentration solution. The system further includes an intermediary gas return duct fluidly coupled to the evaporator and to the absorber. The intermediary gas return duct is configured to direct the intermediary gas received from the absorber to the evaporator.

1 . A microelectronic refrigeration system for cooling an electronic device, the microelectronic refrigeration system configured to contain a refrigerant, a low concentration solution, and an intermediary gas, the microelectronic refrigeration system comprising:
 an evaporator configured to be thermally coupled to the electronic device, to receive and vaporize the refrigerant, and to receive the intermediary gas;   an absorber fluidly coupled to the evaporator, the absorber configured to receive the vaporized refrigerant and the low concentration solution, the vaporized refrigerant dissolving in the low concentration solution to produce a high concentration solution; and   an intermediary gas return duct fluidly coupled to the evaporator and to the absorber, the intermediary gas return duct configured to direct the intermediary gas received from the absorber to the evaporator.   
     
     
         2 . A microelectronic refrigeration system according to  claim 1  further comprising:
 a desorber fluidly coupled to the absorber and configured to receive the high concentration solution therefrom;   a heat source thermally coupled to the desorber and configured to heat the desorber to evaporate the refrigerant from the high concentration solution to yield a low concentration solution; and   a low concentration solution return duct fluidly coupled between the desorber and the absorber, the low concentration solution return duct directing the low concentration solution received from the desorber back to an inlet of the absorber.   
     
     
         3 . A microelectronic refrigeration system according to  claim 2  further comprising a condenser fluidly coupled between the desorber and the evaporator, the condenser configured to condense the vaporized refrigerant to a liquid state. 
     
     
         4 . A microelectronic refrigeration system according to  claim 2  further comprising:
 a flow passage fluidly coupled between the absorber and the desorber; and   a solution heat exchanger fluidly coupled to the flow passage and to the low concentration solution return duct.   
     
     
         5 . A microelectronic refrigeration system according to  claim 2  further comprising:
 a flow passage fluidly coupled between the evaporator and the absorber; and   a gas heat exchanger fluidly coupled to the flow passage and to the intermediary gas return duct.   
     
     
         6 . A microelectronic refrigeration system according to  claim 3  wherein the electronic device comprises an integrated circuit supported by a printed circuit board, and wherein the evaporator and condenser are mounted to opposing surfaces of the printed circuit board. 
     
     
         7 . A microelectronic refrigeration system for cooling an electronic device, the microelectronic refrigeration system configured to contain an intermediary gas, the microelectronic refrigeration system comprising:
 a flow assembly, comprising:
 an evaporator configured to be thermally coupled to the electronic device; 
 an absorber fluidly coupled to the evaporator, the absorber located at a position in the flow assembly that is lower than the position of the evaporator; and 
 a first return duct fluidly coupled to the absorber and to the evaporator; 
   a solvent disposed in the flow assembly; and   a refrigerant disposed in the flow assembly and dissolvable in the solvent;   wherein the flow assembly is configured such that the intermediary gas causes the downward flow of the refrigerant from the evaporator to the absorber.   
     
     
         8 . A microelectronic refrigeration system according to  claim 7  wherein the boiling point of the refrigerant is less than that of the solvent. 
     
     
         9 . A microelectronic refrigeration system according to  claim 7  further comprising:
 a desorber fluidly coupled to the absorber;   a heat source thermally coupled to the desorber; and   a condenser fluidly coupled between the desorber and the evaporator.   
     
     
         10 . A microelectronic refrigeration system according to  claim 9  further comprising a second return duct fluidly coupled to the desorber and to the absorber. 
     
     
         11 . A microelectronic refrigeration system according to  claim 10  wherein the flow assembly is structurally arranged such that the solvent circulates from the absorber, through the desorber, and through the second return duct before returning to the absorber. 
     
     
         12 . A microelectronic refrigeration system according to  claim 7  wherein the flow assembly is structurally arranged such the intermediary gas circulates from the evaporator, through the absorber, and through the first return duct before returning to the absorber. 
     
     
         13 . A microelectronic refrigeration system according to  claim 9  wherein the flow assembly is structurally arranged such that the refrigerant circulates from the evaporator, through the absorber, through the desorber, and through the condenser before returning to the evaporator. 
     
     
         14 . A microelectronic refrigeration system according to  claim 9  wherein the heat source comprises an electrical resistor. 
     
     
         15 . A microelectronic refrigeration system according to  claim 7  further comprising:
 a flow passage fluidly coupled between the evaporator and the absorber; and   a gas heat exchanger fluidly coupled to the flow passage and to the first return duct.   
     
     
         16 . A microelectronic refrigeration system according to  claim 9  further comprising:
 a flow passage fluidly coupled between the absorber and the desorber; and   a liquid head exchanger fluidly coupled to the flow passage and to the second return duct.   
     
     
         17 . A microelectronic refrigeration system according to  claim 7  wherein the solvent comprises water. 
     
     
         18 . A microelectronic refrigeration system according to  claim 17  wherein the refrigerant comprises ammonia. 
     
     
         19 . A method for cooling a microelectronic device that generates heat during operation, the method comprising:
 vaporizing a refrigerant utilizing the generated heat;   introducing an intermediary gas that reacts with the refrigerant to produce a gas-refrigerant composition;   exposing the gas-refrigerant composition to a solvent such that the gas dissociates from the gas-refrigerant composition and the refrigerant dissolves in the solvent to produce a high concentration solution;   heating the high concentration solution to evaporate the refrigerant from the gas-refrigerant solution to yield a low concentration solution and a vaporized refrigerant; and   condensing the vaporized refrigerant to return the refrigerant to a liquid state.   
     
     
         20 . A method according to  claim 19  further comprising the step of selecting the intermediary gas from the group consisting of hydrogen, argon, and helium.