Cooling mechanism for stacked die package and method of manufacturing the same

Abstract

An apparatus for cooling a stacked die package comprises a first die provided above a substrate; a second die above the first die; a cooling fluid in fluid communication with the first die and the second die, the cooling fluid for absorbing thermal energy from the first and the second die; a housing containing the first and second dies, the housing sealing the first and second dies from an environment, wherein the housing further includes a first opening and a second opening, the first and second openings being vertically displaced from one another; a conduit having one end connected to the first opening and the other end connected to the second opening, the conduit allowing the cooling liquid to circulate from the first opening to the second opening; a first temperature sensor being arranged to provide an output that is dependent on a local temperature at the first opening; and a second temperature sensor being arranged to provide an output that is dependent on a local temperature at the second opening, wherein the outputs of the first and second temperature sensors relative to each other are indicative of a level of the cooling fluid.

What is claimed is: 
     
         1 . An apparatus for cooling a stacked die package, comprising:
 a first die above a substrate;   a second die above the first die;   a cooling fluid in fluid communication with the first die and the second die, the cooling fluid for absorbing thermal energy from the first and the second die;   a housing containing the first and second dies, the housing sealing the first and second dies from an environment, wherein the housing includes a first opening and a second opening, the first and second openings being vertically displaced from one another;   a conduit having one end connected to the first opening and the other end connected to the second opening, the conduit allowing the cooling liquid to circulate from the first opening to the second opening;   a first temperature sensor being arranged to provide an output that is dependent on a local temperature at the first opening; and   a second temperature sensor being arranged to provide an output that is dependent on a local temperature at the second opening, wherein the outputs of the first and second temperature sensors relative to each other are indicative of a level of the cooling fluid.   
     
     
         2 . The apparatus of  claim 1 , wherein the first and second temperature sensors are positioned at exterior portions of the housing. 
     
     
         3 . The apparatus of  claim 1 , wherein the second opening is higher than the first opening. 
     
     
         4 . The apparatus of  claim 1 , wherein the second temperature sensor is located proximate to the second opening at a level just below a minimum prescribed cooling fluid level. 
     
     
         5 . The apparatus of  claim 1 , wherein the apparatus is arranged so that a warning signal is initiated when a drop in the level of the cooling fluid below a predetermined threshold level is detected. 
     
     
         6 . The apparatus of  claim 1 , wherein the first and the second temperature sensors are resistive temperature sensors that indicate a change in temperature by a change in electrical resistance. 
     
     
         7 . The apparatus of  claim 1 , comprising a computer arranged to read the measured outputs of the temperature sensors and provide information indicative of an operation property from the measured temperatures. 
     
     
         8 . The apparatus of  claim 7 , wherein the computer is arranged to compare the information indicative of an operating property with information associated with an expected predetermined operating property. 
     
     
         9 . The apparatus of  claim 7 , wherein the computer is arranged to calculate a value that is associated with a level of the cooling fluid. 
     
     
         10 . The apparatus of  claim 1 , further comprising a pump coupled to the conduit for pumping the cooling fluid from the first opening to the second opening. 
     
     
         11 . The apparatus of  claim 10 , wherein the pump pumps the cooling fluid from a bottom region of the housing to an upper region of the housing. 
     
     
         12 . An apparatus for cooling a multi-chip package system, comprising:
 a multi-chip package having two or more dies;   a cooling fluid in fluid communication with the two or more dies, the cooling fluid for absorbing thermal energy from the two or more dies;   a housing containing the multi-chip package, the housing sealing the multi-chip package from the environment, wherein the housing includes a first opening and a second opening, the first and second openings being vertically displaced from one another;   a conduit having one end connected to the first opening and the other end connected to the second opening, the conduit allowing circulating the cooling liquid to circulate from the first opening to the second opening;   a first temperature sensor being arranged to provide an output that is dependent on a local temperature at the first opening; and   a second temperature sensor being arranged to provide an output that is dependent on a local temperature at the second opening, wherein the outputs of the first and second temperature sensors relative to each other are indicative of a level of the cooling fluid.   
     
     
         13 . The apparatus of  claim 12 , wherein the first and second temperature sensors are positioned at exterior portions of the housing. 
     
     
         14 . The apparatus of  claim 12 , wherein the second opening is higher than the first opening. 
     
     
         15 . The apparatus of  claim 12 , wherein the second temperature sensor is located proximate the second opening at a level just below a minimum prescribed cooling fluid level. 
     
     
         16 . The apparatus of  claim 12 , wherein the apparatus is arranged so that a warning signal is initiated when a drop in the level of the cooling fluid below a predetermined threshold level is detected. 
     
     
         17 . The apparatus of  claim 12 , wherein the first and the second temperature sensors are resistive temperature sensors that indicate a change in temperature by a change in electrical resistance. 
     
     
         18 . The apparatus of  claim 12 , comprising a computer arranged to read the measured outputs of the temperature sensors and provide information indicative of an operation property from the measured temperatures. 
     
     
         19 . The apparatus of  claim 18 , wherein the computer is arranged to compare the information indicative of an operating property with information associated with an expected predetermined operating property. 
     
     
         20 . The apparatus of  claim 18 , wherein the computer is arranged to calculate a value that is associated with a level of the cooling fluid.