Abstract:
A method for cooling an electronic device includes forming a spring structure by coupling a plurality of spring elements with a fin portion oriented at an angle, wherein a first end of the fin portion has a narrowed tip; coupling the spring structure with a planar heat-conducting material to form a first heat-conducting layer; positioning the first heat-conducting layer such that the planar heat-conducting material is on top; and placing the first heat-conducting layer over the electronic device such that the fin portion is oriented at an angle toward the electronic device, and such that the narrowed tip of the fin portion is in contact with the top surface of the electronic device.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of, and claims priority from, commonly-owned and co-pending U.S. patent application Ser. No. 11/151,843, filed on Jun. 14, 2005 under Attorney Docket Number YOR920040495US1. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED-RESEARCH OR DEVELOPMENT 
       [0002]    None. 
       INCORPORATION BY REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC 
       [0003]    None. 
       FIELD OF THE INVENTION 
       [0004]    The invention disclosed broadly relates to the field of cooling devices for electronic components, and more particularly relates to the field of heat sinks for microprocessors. 
       BACKGROUND OF THE INVENTION 
       [0005]    During the normal operation of a computer, integrated circuit devices generate significant amounts of heat. This heat must be continuously removed, or the integrated circuit device may overheat, resulting in damage to the device and possibly a reduction in operating performance. Cooling devices, such as heat sinks, have been used in conjunction with integrated circuit devices in order to avoid such overheating. Generally, a passive heat sink in combination with a system fan has provided a relatively cost-effective cooling solution. Recently, however, the power of integrated circuit devices such as microprocessors has increased exponentially, resulting in a significant increase in the amount of heat generated by these devices, thereby necessitating a more efficient cooling solution. 
         [0006]    It is becoming extremely difficult to extract the heat generated by semiconductor devices (processors, in particular) that continue to generate more and more heat in the same amount of space. Heat is typically extracted by coupling a heat spreader and thermal cap to the semiconductor and a heat sink. This coupling typically involves a thermal paste which serves to not only transfer heat but provide some degree of mechanical compliance to compensate for dimensional changes driven by the high temperatures. This paste is often a weak link in the thermal path. Attempts to thin this layer have resulted in failure of the layer when it is exposed to dimensional changes due to heat. 
         [0007]    One approach to this problem includes the use of spring loaded fingers with thermal paste in between them and a thermal paste interface to the chip. This solution is limited in performance by the thermal paste and in design by the requirement for consistent spring loading. Liquid metal has been proposed on its own as a thermal interface material, but could have significant difficulty dealing with large z-axis thermally induced excursions, requiring some compliance elsewhere in the package or (if the largest spacing seen is still thermally acceptable) some sort of edge reservoir design. 
         [0008]    Therefore, a need exists to overcome the problems with the prior art as discussed above, and particularly for a way to cool small electronic devices using a thermally compliant material. 
       SUMMARY OF THE INVENTION 
       [0009]    Briefly, according to an embodiment of the present invention, a method for cooling an electronic device includes steps or acts of: forming a spring structure by coupling a plurality of spring elements with a fin portion oriented at an angle, wherein a first end of the fin portion has a narrowed tip; coupling the spring structure with a planar heat-conducting material to form a first heat-conducting layer; positioning the first heat-conducting layer such that the planar heat-conducting material is on top; and placing the first heat-conducting layer over the electronic device such that the fin portion is oriented at an angle toward the electronic device, and such that the narrowed tip of the fin portion is in contact with the top surface of the electronic device. 
         [0010]    According to another embodiment of the present invention, a method for cooling an electronic device includes the steps or acts as described above, along with an additional step of applying coolant to fill the gaps within the first heat-conducting layer in order to cool the spring elements. 
         [0011]    In another embodiment of the present invention, a method for cooling an electronic device includes steps or acts of: forming a spring structure by densely packing an array of rod elements formed of a semi-rigid, high thermal conductivity material; coupling the spring structure with a planar conformable high thermo conductivity membrane to form a first compressible heat-conducting layer; introducing a second compressible heat-conducting layer; placing the first compressible heat-conducting layer over the second compressible heat-conducting layer to form a coolant structure. Further, a rigid structure is attached to the printed circuit board or other structure beneath the electronic device. This rigid structure surrounds the periphery of the electronic device and supports the cooling device. Coolant is injected into the cooling device through fluid ingress spots in the rigid structure. The terms “above” and “below” are only used herein to suggest relative positions of the components and do not imply any orientation of the components. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The subject matter which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features and also the advantages of the invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings. 
           [0013]      FIG. 1  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements and a plate, according to one embodiment of the present invention. 
           [0014]      FIG. 2  is another cross-sectional side view of the cooling structure of  FIG. 1 . 
           [0015]      FIG. 3  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements, according to one embodiment of the present invention. 
           [0016]      FIG. 4  is another cross-sectional side view of the cooling structure of  FIG. 3 . 
           [0017]      FIG. 5  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements and a liquid, according to one embodiment of the present invention. 
           [0018]      FIG. 6  is another cross-sectional side view of the cooling structure of  FIG. 5 . 
           [0019]      FIG. 7  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements with fins and a plate, according to one embodiment of the present invention. 
           [0020]      FIG. 8  is another cross-sectional side view of the cooling structure of  FIG. 7 . 
           [0021]      FIG. 9  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements with a fin, a plate and a liquid, according to one embodiment of the present invention. 
           [0022]      FIG. 10  is another cross-sectional side view of the cooling structure of  FIG. 9 . 
           [0023]      FIG. 11  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements with a fin, a plate, a seal and a liquid, according to one embodiment of the present invention. 
           [0024]      FIG. 12  is another cross-sectional side view of the cooling structure of  FIG. 11 . 
           [0025]      FIG. 13  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements with a fin, a plate, liquid inlets/outlets and a liquid, according to one embodiment of the present invention. 
           [0026]      FIG. 14  is another cross-sectional side view of the cooling structure of  FIG. 13 . 
           [0027]      FIG. 15  is a perspective view of a series of spring elements in a stacked arrangement. 
           [0028]      FIG. 16  shows the spring elements of  FIG. 15  in a tighter stacked arrangement. 
           [0029]      FIG. 17  shows the spring elements of  FIG. 15  in an even tighter stacked arrangement. 
           [0030]      FIG. 18  is a cross-sectional side view of spring elements in a stacked arrangement. 
           [0031]      FIG. 19  shows the spring elements of  FIG. 18  in a tighter stacked arrangement. 
           [0032]      FIG. 20  shows the spring elements of  FIG. 18  in an even tighter stacked arrangement. 
           [0033]      FIG. 21  shows the spring elements of  FIG. 18  in an even tighter stacked arrangement. 
           [0034]      FIG. 22  is a perspective view of a spring element. 
           [0035]      FIG. 23  is a perspective view of a series of spring elements of  FIG. 22  in a stacked arrangement. 
           [0036]      FIG. 24  shows the spring elements of  FIG. 23  in a tighter stacked arrangement. 
           [0037]      FIG. 25  shows the spring elements of  FIG. 23  in an even tighter stacked arrangement. 
           [0038]      FIG. 26  is a cross-sectional side view of spring elements in a stacked arrangement. 
           [0039]      FIG. 27  shows the spring elements of  FIG. 26  in a tighter stacked arrangement. 
           [0040]      FIG. 28  shows the spring elements of  FIG. 26  in an even tighter stacked arrangement. 
           [0041]      FIG. 29  shows the spring elements of  FIG. 26  in an even tighter stacked arrangement. 
           [0042]      FIG. 30  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including rod elements and a liquid coolant, according to one embodiment of the present invention. 
           [0043]      FIG. 31  is a high level block diagram showing an information processing system useful for implementing one embodiment of the present invention. 
           [0044]      FIG. 32  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure includes a liquid with vaporizing capability, a compliant membrane and spring elements with fins, according to one embodiment of the present invention. 
           [0045]      FIG. 33  is another cross-sectional side view of the cooling structure of  FIG. 32 . 
           [0046]      FIG. 34  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure includes a container for containing a liquid with vaporizing capability, a compliant membrane and spring elements with fins, according to one embodiment of the present invention. 
           [0047]      FIG. 35  is another cross-sectional side view of the cooling structure of  FIG. 34 . 
           [0048]      FIG. 36  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure includes a container for containing a liquid with vaporizing capability and spring elements with fins, according to one embodiment of the present invention. 
           [0049]      FIG. 37  is another cross-sectional side view of the cooling structure of  FIG. 36 . 
           [0050]      FIG. 38  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure includes a container for containing a liquid with vaporizing capability, a compliant membrane and alternating spring elements with fins, according to one embodiment of the present invention. 
           [0051]      FIG. 39  is another cross-sectional side view of the cooling structure of  FIG. 38 . 
           [0052]      FIG. 40  is a cross-sectional side view of a cooling structure for a reduced-size electronic device, the cooling structure includes a container for containing a liquid with vaporizing capability, a compliant membrane and spring elements with fins, according to one embodiment of the present invention. 
           [0053]      FIG. 41  is another cross-sectional side view of the cooling structure of  FIG. 40 . 
       
    
    
     DETAILED DESCRIPTION 
       [0054]    In one embodiment present invention, an array of high thermal conductivity spring elements (made of copper, for example) with a high packing density is included, wherein the spring elements are attached to or integrated with a thermally conductive plate having either a flexible or somewhat rigid top (such as a heat sink or cold cap side). In another embodiment of the present invention, the array of spring elements can be either coupled or placed in contact with (directly or via an interface material) a subject electronic device, such as a semiconductor device. 
         [0055]    In another embodiment of the present invention, the array of spring elements can be coupled to or integrated with a conformable high thermal conductivity bottom membrane. When coupled with a membrane, the array of spring elements can have a relatively small contact area that rapidly increases in cross section to the full cross section of the spring element. This arrangement prevents the end of the spring elements from adding unwanted rigidity to the conformable membrane with minimal thermal resistance. Similarly, the narrowing cross-section feature can also be implemented in the case where the array of spring elements are either coupled or placed in contact with a subject electronic device. However, if a very thin thermal interface material is present between the array of spring elements and the electronic device and there is high spatial frequency content in the lack of flatness of the electronic device surface, it may be desirable to narrow the spring element ends. 
         [0056]    In another embodiment of the present invention, if pure perpendicular motion is desirable upon compression in the case where the array of spring elements are coupled to or integrated with a conformable high thermo conductivity bottom membrane, the array of spring elements may have narrow sections at the ends where they contact a heat sink. Packing density can be as high as practical without interference within an expected compliance range. In another embodiment of the present invention, the array of spring elements can be a particular thickness through their entire length. 
         [0057]    In another embodiment of the present invention, if the space occupied by the array of spring elements can be sealed without compromising compliance, a thermally conductive liquid (such as liquid metal) can be added to reduce the thermal path length. In this embodiment, the present invention takes advantage of useful thermal and physical characteristics of liquid metal. Liquid metal is used as a thermal interface material between the array of spring elements and a microprocessor or a plate coupled thereto. 
         [0058]    Embodiments of the invention include advantages of providing compliance in a location other than (or in addition to) the gap area between the microprocessor and the heat conducting portion of the invention neighboring the microprocessor. The present invention is further advantageous as the forces on the microprocessor exerted by physical changes brought on by heat in the x, y, and z directions do not vary greatly. Further, the present invention allows for z-compliance by utilizing the array of spring elements. Thus, at least some the embodiments eliminate the necessity for compliance in a film disposed between the microprocessor and a heat spreader or heat sink. Additionally, at least some embodiments not require the use of high-viscosity thermal paste, which is not effective in very thin layers. 
         [0059]      FIG. 1  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements and a plate, according to one embodiment of the present invention.  FIG. 1  shows a heat-producing electronic device, a microprocessor  102 , located along the bottom of the assembly  100 . Disposed on the microprocessor  102  is a first layer  104 , which can be a solid layer for providing a heat path from the microprocessor  102  to the upper elements of the assembly  100 . Examples of a solid heat-conducting layer used for this purpose are a thermally conductive adhesive and a solder such as indium. The first layer  104  is a planar surface that rests in contact with the microprocessor  102 . In another embodiment of the present invention, the first layer  104  can be a conformable high thermal conductivity membrane such as a copper sheet. In an embodiment where the first layer  104  is a membrane, an additional layer of high thermal conductivity material would be disposed between the microprocessor  102  and the membrane. 
         [0060]    The cooling structure assembly  100  further includes an array of spring elements  110  that contact or are coupled with the first layer  104 . The array of spring elements  110  comprise a plurality of springs extending in the upper direction away from the source of the heat, the microprocessor  102 . Each of the array of spring elements  110  draw heat away from the microprocessor  102  and allows the heat to radiate out from the increased surface area of the spring elements  110 . Each of the array of spring elements  110  is comprised of a heat conducting material such as copper. Further, each of the array of spring elements  110  exhibits qualities of a spring, which allows for compression and elongation in the z-direction, i.e., the up and down direction, and in the x, y-directions, i.e., the sideways directions. This provides mechanical compliance in accordance with dimensional changes in the microprocessor  102  during use. Note that while the spring elements are shown all bent in the same direction, the springs may be bent in alternate directions to remove any bias. 
         [0061]    Each of the array of spring elements  110  comprises a spring such as a leaf spring or a helix spring for offering resistance when loaded. Each of the array of spring elements  110  provide compliance between the top layer  106  and the microprocessor  102  and works to keep the top layer  106  in close proximity to the microprocessor  102 . The composition and shape of each of the array of spring elements  110  is described in greater detail below. 
         [0062]    The cooling structure assembly  100  further includes a top layer  106  comprising a planar surface, wherein the array of spring elements  110  contact the top layer  106 . The top layer  106  can be a solid layer for providing a heat path from the microprocessor  102  to the upper elements of the assembly  100 . The top layer  106  can be a solid heat-conducting layer such as a thermally conductive adhesive, solder, or solid metal structure. 
         [0063]      FIG. 2  is another cross-sectional side view of the cooling structure of  FIG. 1 .  FIG. 2  shows the cooling structure assembly  100  comprising the top layer  106 , the first layer  104  and the array of spring elements  110  disposed between them.  FIG. 2  also shows the microprocessor  102  at the bottom of the cooling structure assembly  100 . 
         [0064]      FIG. 3  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements, according to one embodiment of the present invention.  FIG. 3  shows the cooling structure assembly  300  comprising the top layer  106 , the microprocessor  102  at the bottom of the cooling structure assembly  300  and the array of spring elements  110  disposed between them. The cooling structure assembly  300  of  FIG. 3  is similar to the cooling structure assembly  100  of  FIG. 1  except for the presence of the first layer  104 . 
         [0065]    In this embodiment of the present invention, the array of spring elements  110  are either coupled or placed in contact with (directly or within an interface material) the microprocessor  102 . In another embodiment, the array of spring elements  110  can have a relatively small profile at the end  302  of the spring elements that contact the microprocessor  102 . The profile would rapidly increase in size to the full cross section of the spring element at the end  304  of the spring elements that contact the top layer  106 . This arrangement prevents the end  302  of the array of spring elements  101  from adding unwanted rigidity to the microprocessor  102  without any substantial thermal resistance. In another embodiment, if a very thin thermal interface material is present between the array of spring elements  110  and the microprocessor  102  and there is high spatial frequency content in the lack of flatness of the surface of the microprocessor  102 , it may be desirable to narrow the spring element ends. In another embodiment of the present invention, the array of spring elements  110  can be a particular thickness through their entire length. 
         [0066]      FIG. 4  is another cross-sectional side view of the cooling structure of  FIG. 3 .  FIG. 4  shows the cooling structure assembly  300  comprising the top layer  106 , the microprocessor  102  at the bottom of the cooling structure assembly  300  and the array of spring elements  110  disposed between them. 
         [0067]      FIG. 5  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements and a liquid, according to one embodiment of the present invention.  FIG. 5  shows the cooling structure assembly  500  comprising a top layer  106 , a microprocessor  102  at the bottom of the cooling structure assembly  500  and an array of spring elements  110  disposed between them. Also included is a thermal interface material  502  and a seal  504  for containing the thermal interface material  502 . The cooling structure assembly  500  of  FIG. 5  is similar to the cooling structure assembly  300  of  FIG. 3  except for the presence of the thermal interface material  502  and the seal  504 . In this embodiment of the present invention, the array of spring elements  110  are either coupled or placed in contact with (directly or within an interface material) the microprocessor  102 . 
         [0068]    The thermal interface material  502  can be a liquid material or a non-rigid solid material. In one embodiment, the thermal interface material  502  is a non-metal liquid, such as oil or water, or a liquid metal such as mercury, gallium or a gallium alloy such as with tin or indium. A liquid  502  can be sealed with a seal  504  or container so as to restrict the escape of the liquid from the desired area over the microprocessor  102 . The liquid nature of the liquid  502  allows the substance to fill the areas created by the gap created between each of the spring elements  110 . The liquid  502  provides a heat path from the microprocessor  102  to the upper elements of the assembly  500  as the heat travels from the microprocessor  102  to the top layer  106 . 
         [0069]      FIG. 6  is another cross-sectional side view of the cooling structure of  FIG. 5 .  FIG. 6  shows the cooling structure assembly  500  comprising a top layer  106 , a microprocessor  102  at the bottom of the cooling structure assembly  500  and an array of spring elements  110  disposed between them. Also included is a thermal interface material  502  and a seal  504  for containing the thermal interface material  502 . 
         [0070]      FIG. 7  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements with fins and a plate, according to one embodiment of the present invention.  FIG. 7  shows the cooling structure assembly  700  comprising the top layer  106 , the first layer  104  and the array of spring elements  710  disposed between them.  FIG. 7  also shows the microprocessor  102  at the bottom of the cooling structure assembly  700 . In another embodiment of the present invention, the first layer  104  can be a conformable high thermal conductivity membrane such as a copper sheet. In an embodiment where the first layer  104  is a membrane, an additional layer of high thermal conductivity material would be disposed between the microprocessor  102  and the membrane. The cooling structure assembly  700  of  FIG. 7  is similar to the cooling structure assembly  100  of  FIG. 1  except for the presence of the elongated fin portion  702  of each of the array of spring elements  110 . 
         [0071]    In another embodiment of the present invention, a coolant would flow between and among the array of spring elements  710 . The coolant can be a liquid material or a gas material. In one embodiment, the coolant is a non-metal liquid, such as oil or water, or a liquid metal such as mercury, gallium or a gallium alloy such as with tin or indium. The liquid nature of the liquid allows the substance to fill the areas created by the gap created between each of the spring elements  710 . The liquid provides a heat path from the microprocessor  102  to the upper elements of the assembly  700  as the heat travels from the microprocessor  102  to the top layer  106 . 
         [0072]    The portion  702  of each of the array of spring elements  710  comprises a plurality of fins extending in the upper direction away from the source of the heat, the microprocessor  102 . The inclusion of the fins serves to effectively increase the surface area of the surface of the first layer  104 , which serves to dissipate heat into a cooling gas or liquid. Each fin draws heat away from the microprocessor  102  and allows the heat to be conducted out from the increased surface area of the fins. The first layer  104  is a planar surface that rests in contact with the microprocessor  102 . 
         [0073]      FIG. 8  is another cross-sectional side view of the cooling structure of  FIG. 7 .  FIG. 8  shows the cooling structure assembly  700  comprising the top layer  106 , the first layer  104  and the array of spring elements  710  disposed between them.  FIG. 8  also shows the microprocessor  102  at the bottom of the cooling structure assembly  700 . 
         [0074]      FIG. 9  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements with a fin, a plate and a liquid, according to one embodiment of the present invention.  FIG. 9  shows the cooling structure assembly  900  comprising the top layer  106 , the first layer  104  and the array of spring elements  710  disposed between them.  FIG. 9  also shows the microprocessor  102  at the bottom of the cooling structure assembly  900 , a cooling gas or liquid  902  (i.e., coolant), a seal  904  and a cooling gas or liquid inlet/outlet pair  906  and  908 . The cooling structure assembly  900  of  FIG. 9  is similar to the cooling structure assembly  700  of  FIG. 7  except for the provisions for handling a coolant  902 , such as seal  904  and inlet/outlet pair  906  and  908 . The cooling structure  900  can also include a pair of flow-restricting end-plates (not shown in this figure but described in greater detail below). 
         [0075]    The coolant  902  can be a gas, a non-metal liquid material, such as oil or water, or a metal liquid material such as mercury, gallium or a gallium alloy such as with tin or indium. The coolant  902  is described in greater detail with reference to  FIG. 7  above. 
         [0076]      FIG. 9  also shows an inlet/outlet pair  906  and  908  for allowing ingress and egress of the coolant  902 . The inlet  906  allows for the intake of the coolant  902  as it is pumped or otherwise pushed or propelled into the assembly  900 . As the coolant  902  travels in the space filling the areas created by the gap created between the microprocessor  102  and the top layer  106 , the coolant  902  absorbs the heat emanated from the first layer  104  and the array of spring elements  710 , including the fin structure  702 . The outlet  908  allows for the egress of the coolant  902  as it is pumped or otherwise pulled or propelled out of the assembly  900  for cooling and eventual recycling into the assembly  900 . 
         [0077]      FIG. 10  is another cross-sectional side view of the cooling structure of  FIG. 9 .  FIG. 10  shows the cooling structure assembly  900  comprising the top layer  106 , the first layer  104  and the array of spring elements  710  disposed between them.  FIG. 10  also shows the microprocessor  102  at the bottom of the cooling structure assembly  900 , a coolant  902  and a seal  904 . The cooling structure  900  can also include a pair of flow-restricting end-plates  1002  and  1004  that fill the area on either end of the array of spring elements  710  in  FIG. 10 . The purpose of the end-plates  1002  and  1004  is to restrict the flow of the coolant  902  into those spaces so as to force the coolant  902  to flow in the area between the multiple spring elements, which is where a higher degree of heat dissipation occurs. 
         [0078]      FIG. 11  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements with a fin, a plate, a seal and a liquid, according to one embodiment of the present invention.  FIG. 11  shows the cooling structure assembly  1100  comprising the top layer  106 , the first layer  104  and the array of spring elements  710  disposed between them.  FIG. 11  also shows the microprocessor  102  at the bottom of the cooling structure assembly  1100 , a coolant  902 , a seal  904 , an internal seal  1106  and a liquid inlet/outlet pair  1102  and  1104 . The cooling structure assembly  1100  of  FIG. 11  is similar to the cooling structure assembly  900  of  FIG. 9  except for the presence of the internal seal  1106  and the liquid inlet/outlet pair  1102  and  1104 . The cooling structure  1100  can also include a pair of flow-restricting end-plates (not shown in this figure but described in greater detail below). 
         [0079]    The internal seal  1106  provides a seal within the space filling the areas created by the gap created between the microprocessor  102  and the top layer  106 . The internal seal  1106  is located at a point in the cooling structure assembly  1100  where the fin structures  702  of the array of spring elements  710  end. That is, the height of the internal seal  1106  is the height at which the fin structure  702  ends and the spring portion begins, for each of the array of spring elements  710 . This is the ideal location for the internal seal  1106 , as it forces the coolant  902  to travel within the area of the fin structures  702  of the array of spring elements  710 , which is where a higher degree of heat dissipation occurs in the cooling structure assembly  1100 . 
         [0080]      FIG. 11  also shows an inlet/outlet pair  1102  and  1104 . The inlet  1102  allows for the intake of the coolant  902  as it is pumped or otherwise pushed or propelled into the assembly  1100 . As the coolant  902  travels in the space filling the areas created by the gap created between the microprocessor  102  and the top layer  106  (namely, the area of the fin structures  702  of the array of spring elements  710 ), the coolant  902  absorbs the heat emanated from the first layer  104  and the fin structures  702  of the array of spring elements  710 . The outlet  1104  allows for the egress of the coolant  902  as it is pumped or otherwise pulled or propelled out of the assembly  1100  for cooling and eventual recycling into the assembly  1100 . 
         [0081]      FIG. 12  is another cross-sectional side view of the cooling structure of  FIG. 11 .  FIG. 12  shows the cooling structure assembly  1100  comprising the top layer  106 , the first layer  104  and the array of spring elements  710  disposed between them.  FIG. 12  also shows the microprocessor  102  at the bottom of the cooling structure assembly  1100 , a thermal interface material  902 , a seal  904  and an internal seal  1106 . The cooling structure  1100  can also include a pair of flow-restricting end-plates  1202  and  1204  that fill the area on either end of the array of spring elements  710  in  FIG. 12 . The purpose of the end-plates  1202  and  1204  is to restrict the flow of the coolant  902  into those spaces so as to force the coolant  902  to flow in the area between the multiple spring elements, which is where a higher degree of heat dissipation occurs. 
         [0082]      FIG. 13  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure including spring elements with a fin, a plate, inlets/outlets and a coolant, according to one embodiment of the present invention.  FIG. 13  shows the cooling structure assembly  1300  comprising the top layer  106 , the first layer  104  and the array of spring elements  710  disposed between them.  FIG. 13  also shows the microprocessor  102  at the bottom of the cooling structure assembly  1100 , a coolant  902 , a seal  904  and a series of inlets/outlets. The cooling structure assembly  1300  of  FIG. 13  is similar to the cooling structure assembly  1100  of  FIG. 11  except for the presence of the series of inlets/outlets and the lack of the internal seal  1106 . The cooling structure  1300  can also include a pair of flow-restricting end-plates (not shown in this figure but described in greater detail below). 
         [0083]      FIG. 13  also shows a series of inlets/outlets. Orifices  1302 ,  1304 ,  1306 ,  1308 ,  1310  and  1312  are designated as inlets. Orifices  1314 ,  1316 ,  1318 ,  1320  and  1322  are designated as outlets. The inlets allow for the intake of the coolant  902  as it is pumped or otherwise pushed or propelled into the assembly  1300 . As the coolant  902  travels in the space filling the areas created by the gap created between the microprocessor  102  and the top layer  106  (namely, the area of the array of spring elements  710 ), the coolant  902  absorbs the heat emanated from the first layer  104  and the array of spring elements  710 . The outlets allow for the egress of the coolant  902  as it is pumped or otherwise pulled or propelled out of the assembly  1300  for cooling and eventual recycling into the assembly  1300 . 
         [0084]      FIG. 14  is another cross-sectional side view of the cooling structure of  FIG. 13 .  FIG. 14  shows the cooling structure assembly  1300  comprising the top layer  106 , the first layer  104  and the array of spring elements  710  disposed between them.  FIG. 14  also shows the microprocessor  102  at the bottom of the cooling structure assembly  1300 , a coolant  902  and a seal  904 . The cooling structure  1300  can also include a pair of flow-restricting end-plates  1402  and  1404  that fill the area on either end of the array of spring elements  710  in  FIG. 14 . 
         [0085]      FIG. 15  is a perspective view of a series of spring elements in a stacked arrangement. A uniform first distance exists between each spring element. Note each of the spring elements comprises a single sheet of material, such as a thermally conductive sheet of metal such as copper, that includes sections that are drilled out or removed. The spring elements of  FIG. 15  are examples of spring elements that can be used in any of the cooling structure assemblies  100 ,  300 ,  500 ,  700 ,  900 ,  1100  and  1300 . The stacked nature of the spring elements of  FIG. 15  show how the spring elements can be arranged for inclusion into any of the aforementioned cooling structure assemblies. Note that  FIGS. 15-17  show the series of spring elements as they are stacked during assembly of a microprocessor assembly that includes the present invention, in one embodiment. 
         [0086]      FIG. 16  shows the spring elements of  FIG. 15  in a tighter stacked arrangement. A uniform second distance exists between each spring element, wherein the second distance is shorter than the first distance.  FIG. 17  shows the spring elements of  FIG. 15  in an even tighter stacked arrangement. A uniform third distance exists between each spring element, wherein the third distance is shorter than the second distance. 
         [0087]      FIG. 18  is a cross-sectional side view of spring elements in a stacked arrangement. A uniform first distance exists between each spring element. Compared to the spring elements of  FIG. 15 , note that the spring elements of  FIG. 18  each include an additional element  1802  on the top end of the spring elements and an additional element  1804  on the bottom end of the spring elements. Note that  FIGS. 18-20  show the series of spring elements as they are stacked during assembly of a microprocessor assembly that includes the present invention, in one embodiment. 
         [0088]      FIG. 19  shows the spring elements of  FIG. 18  in a tighter stacked arrangement. A uniform second distance exists between each spring element, wherein the second distance is shorter than the first distance.  FIG. 20  shows the spring elements of  FIG. 18  in an even tighter stacked arrangement. A uniform third distance exists between each spring element, wherein the third distance is shorter than the second distance.  FIG. 21  shows the spring elements of  FIG. 18  in an even tighter stacked arrangement. A uniform fourth distance exists between each spring element, wherein the fourth distance is shorter than the third distance. Note in  FIG. 21  that the additional element  1802  on the top end of the spring elements and the additional element  1804  on the bottom end of the spring elements has been removed. That is, the spring elements have been trimmed. Note also that the purpose of the contact regions at the top and bottom of the elements is to set the spacing between the spring elements. 
         [0089]      FIG. 22  is a perspective view of a spring element. Note that the spring element comprises a single sheet of material, such as a thermally conductive sheet of metal such as copper, that includes sections that are drilled out or removed. The spring element of  FIG. 15  is an example of a spring element that can be used in any of the cooling structure assemblies  100 ,  300 ,  500 ,  700 ,  900 ,  1100  and  1300 .  FIG. 23  is a perspective view of a series of spring elements of  FIG. 22  in a stacked arrangement. A uniform first distance exists between each spring element. The stacked nature of the spring elements of  FIG. 23  show how the spring elements can be arranged for inclusion into any of the aforementioned cooling structure assemblies. 
         [0090]      FIG. 24  shows the spring elements of  FIG. 23  in a tighter stacked arrangement. A uniform second distance exists between each spring element, wherein the second distance is shorter than the first distance.  FIG. 25  shows the spring elements of  FIG. 23  in an even tighter stacked arrangement. A uniform third distance exists between each spring element, wherein the third distance is shorter than the second distance. 
         [0091]      FIG. 26  is a cross-sectional side view of spring elements in a stacked arrangement. A uniform first distance exists between each spring element. Compared to the spring elements of  FIG. 23 , note that the spring elements of  FIG. 26  each include an additional element  2602  on the top end of the spring elements and an additional element  2604  on the bottom end of the spring elements.  FIG. 27  shows the spring elements of  FIG. 26  in a tighter stacked arrangement. A uniform second distance exists between each spring element, wherein the second distance is shorter than the first distance.  FIG. 28  shows the spring elements of  FIG. 26  in an even tighter stacked arrangement. A uniform third distance exists between each spring element, wherein the third distance is shorter than the second distance.  FIG. 29  shows the spring elements of  FIG. 26  in an even tighter stacked arrangement. A uniform fourth distance exists between each spring element, wherein the fourth distance is shorter than the third distance. Note in  FIG. 29  that the additional element  2602  on the top end of the spring elements and the additional element  2604  on the bottom end of the spring elements has been removed. 
         [0092]      FIG. 30  is a cross-sectional side view of a cooling structure  3000  for an electronic device. The cooling structure  3000  includes rod elements  3020  and a liquid coolant  3024 , according to one embodiment of the present invention.  FIG. 30  shows a heat-producing electronic device  3002 , such as a microprocessor, located along the bottom of the assembly  3000 . The microprocessor  3002  is disposed, such as through welding or soldering, onto a circuit board  3030 . An attachment  3022  surrounds the microprocessor  3002  and provides a base for placing a rigid structure  3028  such that it is located above or over the microprocessor  3002 . The structure  3010  is also a rigid structure that may be integrated with or separate from the rigid structure  3028 . Disposed on the microprocessor  3002  is a first layer  3004 , which is a conformable high thermo conductivity membrane for providing a heat path from the microprocessor  3002  to the upper elements of the assembly  3000 . The first layer  3004  is a planar surface that rests in contact with the microprocessor  3002 . Disposed above the first layer  3004  is a second layer  3006 , which can also be a conformable high thermo conductivity membrane for providing a heat path from the microprocessor  3002  to the upper elements of the assembly  3000 . The second layer  3006  is a planar surface that rests in contact with a compressible material layer  3008 , such as rubber. The layer  3006  is used as an adhesion/water-seal layer that is soft or pliable. 
         [0093]    The term membrane refers to a thin substrate used to separate different layers or materials. There is no inherent application of tension assumed in conjunction with use of this term. The membranes described above can be foils or flexible sheets. 
         [0094]    The cooling structure assembly  3000  further includes an array of rigid rod elements  3020  that contact or are coupled with the first layer  3004  and the second layer  3006 . The array of rigid rod elements  3020  are disposed between the first layer  3004  and the second layer  3006 . The array of rod elements  3020  comprises a plurality of rods or small cylinders extending in a direction away from the source of the heat, the microprocessor  3002 . Each of the array of rod elements  3020  draw heat away from the microprocessor  3002  and allows the heat to radiate out from the increased surface area of the rod elements  3020 . Each of the array of rod elements  3020  comprises a semi-rigid, high thermal conductivity material, such as copper. Further, the array of rod elements  3020  are packed densely. Equivalently, a set of fins can be used in place of the rods. 
         [0095]    Due to the conformable nature of the first layer  3004  and the second layer  3006 , each individual rod element has the freedom to move upwards or downwards. Further, due to the compressible nature of the compressible material layer  3008 , each individual rod element has the freedom to move upwards into the compressible material layer  3008  or downwards away from compressible material layer  3008 , as the dimensions of the microprocessor  3002  change due to heat buildup during use. Thus, the compressible material layer  3008  allows for compression and elongation in the z-direction, i.e., the up and down direction, and in the x, y-directions, i.e., the sideways directions. This provides heat compliance in accordance with dimensional changes in the microprocessor  102  during use. 
         [0096]      FIG. 30  also shows that a thermal interface material  3024  can be located in the gap created between the structure  3010  and the structure  3028  and in the area between first layer  3004  and the second layer  3006 . The thermal interface material  3024  can be a non-metal liquid thermal interface material, such as oil or water, or a metal liquid thermal interface material such as mercury, gallium or a gallium alloy such as with tin or indium. The liquid  3024  can be sealed so as to restrict the escape of the liquid from the desired area over the microprocessor  3002 . The liquid nature of the liquid  3024  allows the substance to fill the areas created by the gap created between the structure  3010  and the structure  3028  and in the area between first layer  3004  and the second layer  3006 . The liquid  3024  provides a heat path from the microprocessor  3002  to the upper elements of the assembly  3000  as the heat travels from the microprocessor  3002  upwards. 
         [0097]      FIG. 30  also shows a liquid inlet/outlet pair  3016  and  3018 . The liquid inlet  3016  allows for the intake of the liquid thermal interface material  3024  as it is pumped or otherwise pushed or propelled into the assembly  3000 . As the liquid thermal interface material  3024  travels in the space filling the areas created by the gap created between the structure  3010  and the structure  3028  and in the area between first layer  3004  and the second layer  3006 , the liquid thermal interface material  3024  absorbs the heat emanated from the first layer  3004  and the array of rod elements  3020 . The liquid outlet  3018  allows for the egress of the liquid thermal interface material  3024  as it is pumped or otherwise pulled or propelled out of the assembly  3000  for cooling and eventual recycling into the assembly  3000 . 
         [0098]      FIG. 32  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure includes a liquid with vaporizing capability, a compliant membrane and spring elements with fins, according to one embodiment of the present invention. 
         [0099]      FIG. 32  shows the cooling structure assembly  3200  comprising a top layer  3206 , a microprocessor  3202  at the bottom of the cooling structure assembly  3200  and an array of spring elements  3210  disposed between them. In the space between the top layer  3206  and the microprocessor  3202  is the presence of a vaporizing liquid  3201 . The cooling structure assembly  3200  of  FIG. 32  is similar to the cooling structure assembly  500  of  FIG. 5  except for the presence of the vaporizing liquid  3201  and the wicking capabilities of the spring elements  3210 . Wicking can be generated by the surface tension in the narrow spaces between the elements and/or by porous coatings in the surfaces of the elements. In this embodiment of the present invention, the array of spring elements  3210  are coupled or placed in contact with a compliant interface substrate  3203  disposed over the microprocessor  3202 . 
         [0100]    The liquid  3201  can be any liquid that can be used to cool the microprocessor  3202 , including any commercially available microprocessor. Such a liquid  3201  can have qualities such that it evaporates or vaporizes at temperatures that are normally reached by the microprocessor  3202  during use. The vapor typically moves upwards toward the top layer  3206  and away through the spaces between the spring elements, areas which are further away from the microprocessor  3202  and thus at a lower temperature. This leads to condensation whereby the vapor returns to liquid form. Upon returning to liquid form, the substance is pulled by wicking forces and/or gravity back into the area above the microprocessor  3202  whereby the liquid  3201  resumes its heat absorbing function. The spring portion of the array of spring elements  3210  may serve as a pathway for returning the condensed liquid  3201  to the area above the microprocessor  3202 . The larger diameter passageways formed near the base of the elements  3210  where they narrow and attach to membrane  3203  provide low resistance flow channels to allow fluid  3201  to distribute easily across the stack of elements  3210 . The liquid  3201  can be sealed with a seal or container so as to restrict the escape of the liquid from the desired area over the microprocessor  3202 . The liquid nature and surface tensions of the liquid  3201  allows the substance to fill the areas created by the gap created between each of the spring elements  3210 . The lower portions of the spring elements  3210  provide a heat path into the liquid, causing vaporization as well as providing a conduction path to the top surface  3206 . 
         [0101]      FIG. 33  is another cross-sectional side view of the cooling structure of  FIG. 32 . The cooling structure assembly  3200  of  FIG. 33  is similar to the cooling structure assembly  600  of  FIG. 6  except for the presence of the vaporizing liquid  3201  and the wicking capabilities of the spring elements  3210 . 
         [0102]      FIG. 34  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure includes a container for containing a liquid with vaporizing capability, a compliant membrane and spring elements with fins, according to one embodiment of the present invention. 
         [0103]      FIG. 34  shows the cooling structure assembly  3400  comprising a top layer  3406 , a microprocessor  3402  at the bottom of the cooling structure assembly  3400  and an array of spring elements  3410  disposed between them. The cooling structure assembly  3400  of  FIG. 34  is similar to the cooling structure assembly  500  of  FIG. 5  except for the presence of a vaporizing liquid, the wicking capabilities of the spring elements  3410  and the seal  3430 . In this embodiment of the present invention, the array of spring elements  3410  are either coupled or placed in contact with (directly or within an interface material) the microprocessor  3402 . 
         [0104]    In the space between the top layer  3406  and the microprocessor  3402  can be a vaporizing liquid, identical to the liquid  3201  above. The liquid can be sealed with a seal  3430  or container so as to restrict the escape of the liquid from the desired area over the microprocessor  3402 . The liquid nature of the liquid allows the substance to fill the areas created by the gap created between each of the spring elements  3410 . The lower portions of the spring elements  3410  provide a heat path into the liquid, causing vaporization as well as providing a conduction path to the top surface  3406 . 
         [0105]    In another embodiment of the present invention, the cooling structure includes a condenser coupled to the seal  3430 , whereby the condenser allows the liquid in a vaporized form to enter into the condenser, condense into a liquid form and then exit the condenser and return to the space contained by seal  3430 . 
         [0106]      FIG. 35  is another cross-sectional side view of the cooling structure of  FIG. 34 . The cooling structure assembly  3400  of  FIG. 35  is similar to the cooling structure assembly  600  of  FIG. 6  except for the presence of a vaporizing liquid, the wicking capabilities of the spring elements  3410  and the seal  3430 . 
         [0107]    One embodiment of the invention comprises creating a locally and globally compliant cooling structure with an integrated vapor chamber made of a high thermal conductivity material, such as copper, wherein the vapor chamber structure wicks the liquid, heats and evaporates the liquid into vapor, and includes liquid return paths when the vapor condenses. At least some embodiments allow the use of very thin thermal interface materials of lower thermal conductivity. At least some embodiments provide reasonable compliance in the X-Y plane as well due to the thin bottom layer  3403 . Virtually any thermal interface material (TIM) may be used. A heat-generating electronic device package can be created with a much larger surface area to which a heat sink or cold cap can be coupled. This provides for very high heat removal capability. 
         [0108]    At least some embodiments comprise creating an array of high thermal conductivity (such as copper) elements comprising both a spring portion (potentially doubling as a liquid return path) and a wicking fin portion with a high packing density attached to or integrated into either a flexible or relatively rigid top plate. 
         [0109]    The wicking fin portion can also provide liquid distribution channels below the surface of the evaporating liquid, for lower pressure drop and higher peak heat transfer capability. The aforementioned elements are also attached to/integrated into a conformable high thermal conductivity bottom (i.e., chip-side) membrane. When attached to a membrane, the spring elements have a small contact area that rapidly increase in cross section to the full cross section of the spring elements. This prevents the ends of the spring elements from adding unwanted rigidity to the conformable membrane without adding substantial thermal resistance. Packing density is as high as practical without interference within the expected compliance range while maintaining vapor chamber performance. Packing density and surface finish in the wicking region can be optimized to improve capillary action and provide enhanced heat-transfer/boiling surfaces. 
         [0110]    In an embodiment of the present invention, the spring elements can have a particular thickness through their entire length, unlike what is shown in the  FIGS. 32-35 . 
         [0111]    In another embodiment of the present invention, while the spring and wicking portions can comprise differing sections of each array element, as shown in  FIG. 32 , the functions of wicking and spring force can be more integrated. Such an arrangement serves to separately optimize the behavior of each section (spring and wicking) of the array elements. 
         [0112]      FIG. 34  shows one implementation for sealing the apparatus and allowing for liquid return paths within the array assembly.  FIG. 34  shows the vapor chamber significantly larger than the chip. This implementation provides for a larger contact area for the heat sink or cold cap and allows more reservoir space that is not in close proximity to the chip. Note that nothing prevents the use of a separate condenser by routing the vapor away to the condenser and returning the condensate to the wicking area. 
         [0113]      FIG. 36  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure includes a container for containing a liquid with vaporizing capability and spring elements with fins, according to one embodiment of the present invention. 
         [0114]      FIG. 36  shows the cooling structure assembly  3600  comprising a top layer  3606 , a microprocessor  3602  at the bottom of the cooling structure assembly  3600  and an array of spring elements  3610  disposed between them. The cooling structure assembly  3600  of  FIG. 36  is similar to the cooling structure assembly  500  of  FIG. 5  except for the presence of a vaporizing liquid, the wicking capabilities of the spring elements  3610  and the seal  3630 . In this embodiment of the present invention, the array of spring elements  3610  are either coupled or placed in contact with (directly or within an interface material) the microprocessor  3602 . 
         [0115]    In the space between the top layer  3606  and the microprocessor  3602  can be a vaporizing liquid, identical to the liquid  3601  above. The liquid can be sealed with a seal  3630  or container so as to restrict the escape of the liquid from the desired area over the microprocessor  3602  and to maintain the liquid and vapor separate from the external atmosphere as it&#39;s pressure may be substantially different from atmospheric pressure. The nature of the liquid allows the substance to fill the areas created by the gap created between each of the spring elements  3610 . The liquid provides a heat path from the microprocessor  3602  to the upper elements of the assembly  3600  as the heat travels from the microprocessor  3602  to the top layer  3606 . 
         [0116]    In another embodiment of the present invention, the cooling structure includes a condenser coupled to the seal  3630 , whereby the condenser allows the liquid in a vaporized form to enter into the condenser, condense into a liquid form and then exit the condenser and return to the space contained by seal  3630 . Additional seal  3603  provides a seal for the liquid  3601  at the juncture between the microprocessor  3602  and the seal  3630 . 
         [0117]      FIG. 37  is another cross-sectional side view of the cooling structure of  FIG. 34 . The cooling structure assembly  3600  of  FIG. 37  is similar to the cooling structure assembly  600  of  FIG. 6  except for the presence of a vaporizing liquid, the wicking capabilities of the spring elements  3610  and the seal  3630 . 
         [0118]      FIG. 38  is a cross-sectional side view of a cooling structure for an electronic device, the cooling structure includes a container for containing a liquid with vaporizing capability, a compliant membrane and alternating spring elements with fins, according to one embodiment of the present invention. 
         [0119]      FIG. 38  shows the cooling structure assembly  3800  comprising a top layer  3806 , a microprocessor  3802  at the bottom of the cooling structure assembly  3800  and an array of spring elements  3810  disposed between them. The cooling structure assembly  3800  of  FIG. 38  is similar to the cooling structure assembly  500  of  FIG. 5  except for the presence of a vaporizing liquid, the wicking capabilities of the spring elements  3810  and the seal  3830 . In this embodiment of the present invention, the array of spring elements  3810  are either coupled or placed in contact with (directly or within an interface material) the microprocessor  3802 . 
         [0120]    In the space between the top layer  3806  and the microprocessor  3802  can be a vaporizing liquid, identical to the liquid  3801  above. The liquid can be sealed with a seal  3830  or container so as to restrict the escape of the liquid from the desired area over the microprocessor  3802 . The liquid nature of the liquid allows the substance to fill the areas created by the gap created between each of the spring elements  3810 . The liquid provides a heat path from the microprocessor  3802  to the upper elements of the assembly  3800  as the heat travels from the microprocessor  3802  to the top layer  38606 . 
         [0121]    In another embodiment of the present invention, the spring elements  3810  alternate in length and size, as shown by alternating spring elements  3850  and  3851 . 
         [0122]      FIG. 39  is another cross-sectional side view of the cooling structure of  FIG. 38 . The cooling structure assembly  3800  of  FIG. 39  is similar to the cooling structure assembly  600  of  FIG. 6  except for the presence of a vaporizing liquid, the wicking capabilities of the spring elements  3810  and the seal  3830 . 
         [0123]      FIG. 40  is a cross-sectional side view of a cooling structure for a reduced-size electronic device, the cooling structure includes a container for containing a liquid with vaporizing capability, a compliant membrane and spring elements with fins, according to one embodiment of the present invention. 
         [0124]      FIG. 40  shows the cooling structure assembly  4000  comprising a top layer  4006 , a microprocessor  4002  at the bottom of the cooling structure assembly  4000  and an array of spring elements  4010  disposed between them. The cooling structure assembly  4000  of  FIG. 40  is similar to the cooling structure assembly  500  of  FIG. 5  except for the presence of a vaporizing liquid, the wicking capabilities of the spring elements  4010  and the seal  4030 . In this embodiment of the present invention, the array of spring elements  4010  are either coupled or placed in contact with (directly or within an interface material) the microprocessor  4002 . 
         [0125]    In the space between the top layer  4006  and the microprocessor  4002  can be a vaporizing liquid, identical to the liquid  3201 . The liquid can be sealed with a seal  4030  or container so as to restrict the escape of the liquid from the desired area over the microprocessor  4002 . The liquid nature and surface tension of the liquid allows the substance to fill the areas created by the gap created between each of the spring elements The lower portions of the spring elements  4010  provide a heat path into the liquid, causing vaporization as well as providing a conduction path to the top surface  4006 . 
         [0126]    In another embodiment of the present invention, the cooling structure includes a condenser coupled to the seal  4030 , whereby the condenser allows the liquid in a vaporized form to enter into the condenser, condense into a liquid form and then exit the condenser and return to the space contained by seal  4030 . 
         [0127]      FIG. 41  is another cross-sectional side view of the cooling structure of  FIG. 40 . The cooling structure assembly  4000  of  FIG. 41  is similar to the cooling structure assembly  600  of  FIG. 6  except for the presence of a vaporizing liquid, the wicking capabilities of the spring elements  4010  and the seal  4030 . 
         [0128]    The present invention can be utilized for cooling any of a variety of electronic devices. In one embodiment of the present invention, the present invention is used to cool a microprocessor of an information processing system such as a computer.  FIG. 31  is a high level block diagram showing an information processing system useful for implementing one embodiment of the present invention. The computer system includes one or more processors, such as processor  3104 . The processor  3104  is connected to a communication infrastructure  3102  (e.g., a communications bus, cross-over bar, or network). Various software embodiments are described in terms of this exemplary computer system. After reading this description, it will become apparent to a person of ordinary skill in the relevant art(s) how to implement the invention using other computer systems and/or computer architectures. 
         [0129]    The computer system can include a display interface  3108  that forwards graphics, text, and other data from the communication infrastructure  3102  (or from a frame buffer not shown) for display on the display unit  3110 . The computer system also includes a main memory  3106 , preferably random access memory (RAM), and may also include a secondary memory  3112 . The secondary memory  3112  may include, for example, a hard disk drive  3114  and/or a removable storage drive  3116 , representing a floppy disk drive, a magnetic tape drive, an optical disk drive, etc. The removable storage drive  3116  reads from and/or writes to a removable storage unit  3118  in a manner well known to those having ordinary skill in the art. Removable storage unit  3118 , represents a floppy disk, a compact disc, magnetic tape, optical disk, etc. which is read by and written to by removable storage drive  3116 . As will be appreciated, the removable storage unit  3118  includes a computer readable medium having stored therein computer software and/or data. 
         [0130]    In alternative embodiments, the secondary memory  3112  may include other similar means for allowing computer programs or other instructions to be loaded into the computer system. Such means may include, for example, a removable storage unit  3122  and an interface  3120 . Examples of such may include a program cartridge and cartridge interface (such as that found in video game devices), a removable memory chip (such as an EPROM, or PROM) and associated socket, and other removable storage units  3122  and interfaces  3120  which allow software and data to be transferred from the removable storage unit  3122  to the computer system. 
         [0131]    The computer system may also include a communications interface  3124 . Communications interface  3124  allows software and data to be transferred between the computer system and external devices. Examples of communications interface  3124  may include a modem, a network interface (such as an Ethernet card), a communications port, a PCMCIA slot and card, etc. Software and data transferred via communications interface  3124  are in the form of signals which may be, for example, electronic, electromagnetic, optical, or other signals capable of being received by communications interface  3124 . These signals are provided to communications interface  3124  via a communications path (i.e., channel)  3126 . This channel  3126  carries signals and may be implemented using wire or cable, fiber optics, a phone line, a cellular phone link, an RF link, and/or other communications channels. 
         [0132]    In this document, the terms “computer program medium,” “computer usable medium,” and “computer readable medium” are used to generally refer to media such as main memory  3106  and secondary memory  3112 , removable storage drive  3116 , a hard disk installed in hard disk drive  3114 , and signals. These computer program products are means for providing software to the computer system. The computer readable medium allows the computer system to read data, instructions, messages or message packets, and other computer readable information from the computer readable medium. The computer readable medium, for example, may include non-volatile memory, such as a floppy disk, ROM, flash memory, disk drive memory, a CD-ROM, and other permanent storage. It is useful, for example, for transporting information, such as data and computer instructions, between computer systems. Furthermore, the computer readable medium may comprise computer readable information in a transitory state medium such as a network link and/or a network interface, including a wired network or a wireless network, that allow a computer to read such computer readable information. 
         [0133]    Computer programs (also called computer control logic) are stored in main memory  3106  and/or secondary memory  3112 . Computer programs may also be received via communications interface  3124 . Such computer programs, when executed, enable the computer system to perform the features of the present invention as discussed herein. In particular, the computer programs, when executed, enable the processor  3104  to perform the features of the computer system. Accordingly, such computer programs represent controllers of the computer system. 
         [0134]    Although specific embodiments of the invention have been disclosed, those having ordinary skill in the art will understand that changes can be made to the specific embodiments without departing from the spirit and scope of the invention. The scope of the invention is not to be restricted, therefore, to the specific embodiments. Furthermore, it is intended that the appended claims cover any and all such applications, modifications, and embodiments within the scope of the present invention.