Vapor chamber structure with improved wick and method for manufacturing the same

• US 20090025910A1
• Filed: 07/27/2007
• Published: 01/29/2009
• Est. Priority Date: 07/27/2007
• Status: Abandoned Application

• Current Assignee: Amulaire Thermal Technology, Inc.
• Original Assignee: Amulaire Thermal Technology, Inc.
• Inventors: Hoffman, Paul, Hong, Chu-wan, Semenic, Tadej, Lee, Che-Yin, Tandon, Rajiv, Remsburg, Ralph
• Application Number:
  US11/878,809
• Publication Number:
  US 20090025910A1
• Time in Patent Office: Days
• US Class Current: 165/104.260
• CPC Class Codes: F28D 15/046 characterised by the material or the construction of the capillary structure
• CPC Class Codes: H01L 23/427 Cooling by change of state, e.g. use of heat pipes by liquefied gas H01L23/445
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: Y10T 29/49353 Heat pipe device making

Abstract

A vapor chamber structure includes a casing, a working fluid, and an improved wick layer. The casing has an airtight vacuum chamber. The working fluid is filled into the airtight vacuum chamber. The wick layer is formed on a surface of the airtight vacuum chamber. Therefore, the present invention can increase the backflow velocity of the working fluid and improve the boiling of the working fluid due to the match of the improved wick structure. Because the backflow velocity and boiling of the working fluid is increased, the heat-transmitting efficiency is increased.

Claims

1. A vapor chamber structure, comprising:

a casing having an upper casing and a lower casing to form an airtight vacuum chamber;

a working fluid filled into the airtight vacuum chamber;

and an improved wick layer formed on an internal surface of the airtight vacuum chamber.

2. The vapor chamber structure as claimed in claim 1, wherein the improved wick layer is in a discontinuous fashion and at least one separated portion of the wick is disposed to isolate the wick layer.

3. The vapor chamber structure as claimed in claim 1, further comprising at least one structure strengthening body arranged in the airtight vacuum chamber for supporting the upper casing and the lower casing.

4. The vapor chamber structure as claimed in claim 3, wherein one or more structure strengthening bodies has a solid post and a wick layer circumferentially covering an external surface of the solid post.

5. The vapor chamber structure as claimed in claim 1, wherein one or more backflow accelerating bodies has a wick post and a metal solid layer covered circumferentially on an external surface of the wick post.

6. The vapor chamber structure as claimed in claim 1, wherein at least one channel and at least one micro-channel are disposed on the casing.

7. The vapor chamber structure as claimed in claim 6, wherein a width of each channel is greater than 200 microns and a width of each micro-channel is smaller than 200 microns.

8. The vapor chamber structure as claimed in claim 1, wherein at least one channel is disposed on the lower casing, the improved wick layer comprises a first wick layer formed by a first wick element contacting the upper casing and a second wick layer formed by a second wick element contacting the lower casing.

9. The vapor chamber structure as claimed in claim 8, wherein a size of the second wick element is different from a size of the first wick element.

10. The vapor chamber structure as claimed in claim 8, wherein each channel is filled by the first wick element.

11. The vapor chamber structure as claimed in claim 1, wherein the thickness of the improved wick layer is variable depending on a travel path of the working fluid.

12. The vapor chamber structure as claimed in claim 11, wherein the thickness of a central portion of the improved wick layer disposed on the upper casing is thinner than the thickness of a peripheral portion.

13. The vapor chamber structure as claimed in claim 12, wherein at least one micro-channel is formed on the improved wick layer disposed on the upper casing.

14. The vapor chamber structure as claimed in claim 11, wherein the thickness of a central portion of the improved wick layer disposed on the lower casing is thicker than the thickness of a peripheral portion.

15. The vapor chamber structure as claimed in claim 14, wherein at least one micro-channel is formed on the improved wick layer disposed on the lower casing.

16. The vapor chamber structure as claimed in claim 1, wherein the improved wick has at least one wick layer formed by second wick elements are respectively placed in predetermined patches in the wick layer formed by first wick elements.

17. The vapor chamber structure as claimed in claim 16, wherein each wick layer formed by second wick elements are placed in an isolated patch in the wick layer formed by first wick elements.

18. The vapor chamber structure as claimed in claim 16, wherein the wick layer formed by second wick elements has interdigitated portions with respect to the first wick layer in a plan direction.

19. The vapor chamber structure as claimed in claim 16, wherein the wick layer formed by second wick elements has interdigitated portions with respect to the first wick layer in a height direction.

20. The vapor chamber structure as claimed in claim 16, wherein the wick layer formed by second wick elements has radial portions in a plan direction.

21. The vapor chamber structure as claimed in claim 16, wherein the wick layer formed by second wick elements has circular portions in a plan direction.

22. The vapor chamber structure as claimed in claim 1, wherein the improved wick layer comprises wick elements having at least two sizes.

23. The vapor chamber structure as claimed in claim 22, wherein the wick elements having different sizes are arranged in a continuous gradient or step-wise gradient of element sizes to form into the wick layer.

24. The vapor chamber structure as claimed in claim 22, wherein the improved wick layer is a wick structure formed by a plurality of wick clusters and each wick cluster is formed by combining wick elements having different sizes with each other.

25. The vapor chamber structure as claimed in claim 22, wherein the wick layer is formed by stacking the wick elements upon each other in decreasing sizes with the largest wick elements on the bottom.

26. The vapor chamber structure as claimed in claim 22, wherein the wick layer is formed by stacking the wick elements upon each other in increasing sizes with the smallest wick elements on the bottom.

27. The vapor chamber structure as claimed in claim 1, wherein each exterior surface of one or more of the wick elements has a coated layer.

28. The vapor chamber structure as claimed in claim 1, wherein at least one portion of the wick layer comprises a multi-layered wick layer formed by stacking at least one first wick layer and at least one second wick layer upon each other layer with the first wick layer on the bottom.

29. The vapor chamber structure as claimed in claim 28, wherein the second wick layer between two first layers in the multi-layered wick layer is separated into at least one isolated portion.

30. The vapor chamber structure as claimed in claim 1, wherein wick elements of the wick layer completely fill the airtight vacuum chamber.

31. The vapor chamber structure as claimed in claim 30, wherein at least one second wick layer formed by second wick elements are embedded inside the chamber to form a multi-layered structure.

32. The vapor chamber structure as claimed in claim 1, wherein at least one protrusion with predetermined height extends from the casing forming an extended surface and each extended surface is coated with the wick layer.

33. The vapor chamber structure as claimed in claim 1, wherein at least one depression is disposed on the casing forming an extended surface and each extended surface is coated with the wick layer.

34. The vapor chamber structure as claimed in claim 1, further comprising at least one filling pipe communicated with the airtight vacuum chamber via a joint opening of the casing.

35. The vapor chamber structure as claimed in claim 1, wherein the length of the filling pipe is larger than a double length of a diameter of the filling pipe.

36. The vapor chamber as claimed in claim 1, wherein the wick layer is pre-fabricated outside of and free from the casing, and is subsequently affixed to the interior of the casing.

37. The vapor chamber structure as claimed in claim 36, wherein the wick layer is in a discontinuous fashion and at least one separated portion of the wick is disposed to isolate the wick layer.

38. The vapor chamber structure as claimed in claim 36, further comprising at least one structure strengthening body arranged in the wick for supporting the upper casing and the lower casing.

39. The vapor chamber structure as claimed in claim 36, wherein one or more structure strengthening bodies has a solid post and a wick layer circumferentially covering an external surface of the solid post.

40. The vapor chamber structure as claimed in claim 36, wherein one or more backflow accelerating bodies has a wick post and a metal solid layer covered circumferentially on an external surface of the wick post.

41. The vapor chamber structure as claimed in claim 36, wherein at least one channel and at least one micro-channel are disposed on the casing.

42. The vapor chamber structure as claimed in claim 41, wherein a width of each channel is greater than 200 microns and a width of each micro-channel is smaller than 200 microns.

43. The vapor chamber structure as claimed in claim 36, wherein at least one channel is disposed on the lower casing, the wick layer comprises a first wick layer formed by a first wick element contacting the upper casing and a second wick layer formed by a second wick element contacting the lower casing.

44. The vapor chamber structure as claimed in claim 43, wherein a size of the second wick element is different from a size of the first wick element.

45. The vapor chamber structure as claimed in claim 43, wherein each channel is filled by the first wick element.

46. The vapor chamber structure as claimed in claim 36, wherein the thickness of the wick layer is variable depending on a travel path of the working fluid.

47. The vapor chamber structure as claimed in claim 46, wherein the thickness of a central portion of the wick layer disposed on the upper casing is thinner than the thickness of a peripheral portion.

48. The vapor chamber structure as claimed in claim 47, wherein at least one micro-channel is formed on the wick layer disposed on the upper casing.

49. The vapor chamber structure as claimed in claim 46, wherein the thickness of a central portion of the wick layer disposed on the lower casing is thicker than the thickness of a peripheral portion.

50. The vapor chamber structure as claimed in claim 49, wherein at least one micro-channel is formed on the wick layer disposed on the lower casing.

51. The vapor chamber structure as claimed in claim 36, wherein at least one wick layer formed by second wick elements are respectively placed in predetermined patches in the wick layer formed by first wick elements.

52. The vapor chamber structure as claimed in claim 51, wherein each wick layer formed by second wick elements are placed in an isolated patch in the wick layer formed by first wick elements.

53. The vapor chamber structure as claimed in claim 51, wherein the wick layer formed by second wick elements has interdigitated portions with respect to the first wick layer in a plan direction.

54. The vapor chamber structure as claimed in claim 51, wherein the wick layer formed by second wick elements has interdigitated portions with respect to the first wick layer in a height direction.

55. The vapor chamber structure as claimed in claim 51, wherein the wick layer formed by second wick elements has radial portions in a plan direction.

56. The vapor chamber structure as claimed in claim 51, wherein the wick layer formed by second wick elements has circular portions in a plan direction.

57. The vapor chamber structure as claimed in claim 36, wherein the wick layer comprises wick elements having at least two sizes.

58. The vapor chamber structure as claimed in claim 57, wherein the wick elements having different sizes are arranged in a continuous gradient or step-wise gradient of wick element sizes to form into the wick layer.

59. The vapor chamber structure as claimed in claim 57, wherein the wick layer is a wick structure formed by a plurality of wick clusters and each wick cluster is formed by combining wick elements having different sizes with each other.

60. The vapor chamber structure as claimed in claim 57, wherein the wick layer is formed by stacking the wick elements upon each other in decreasing sizes with the largest wick elements on the bottom.

61. The vapor chamber structure as claimed in claim 57, wherein the wick layer is formed by stacking the wick elements upon each other in increasing sizes with the smallest wick elements on the bottom.

62. The vapor chamber structure as claimed in claim 36, wherein each exterior surface of one or more of the wick elements has a coated layer.

63. The vapor chamber structure as claimed in claim 36, wherein at least one portion of the wick layer comprises a multi-layered wick layer formed by stacking at least one first wick layer and at least one second wick layer upon each other layer with the first wick layer on the bottom.

64. The vapor chamber structure as claimed in claim 63, wherein the second wick layer between two first layers in the multi-layered wick layer is separated into at least one isolated portion.

65. The vapor chamber structure as claimed in claim 36, wherein wick elements of the wick layer completely fill the airtight vacuum chamber.

66. The vapor chamber structure as claimed in claim 65, wherein at least one second wick layer formed by second wick elements are embedded inside the wick to form a multi-layered structure.

67. The vapor chamber structure as claimed in claim 36, wherein at least one protrusion with predetermined height extends from the casing forming an extended surface and each extended surface is coated with the wick layer.

68. The vapor chamber structure as claimed in claim 36, wherein at least one depression is disposed on the casing forming an extended surface and each extended surface is coated with the wick layer.

69. The vapor chamber structure as claimed in claim 36, further comprising at least one filling pipe communicated with the airtight vacuum chamber via a joint opening of the casing.

70. The vapor chamber structure as claimed in claim 36, wherein the length of the filling pipe is larger than a double length of a diameter of the filling pipe.

71. A method for manufacturing a vapor chamber structure, comprising:

providing a casing composed of an upper casing and a lower casing;

forming a wick layer on an internal surface of the casing;

assembling the upper casing and the lower casing together to form a chamber;

pumping away air from the chamber; and

filling a working fluid into the chamber and sealing the casing.

72. The method for manufacturing a vapor chamber structure as claimed in claim 71, wherein a plurality of structures are arranged between the upper casing and the lower casing and comprise at least one backflow accelerating body, or at least one channel, or at least one micro-channel, or a multi-layered wick layer.

73. A method for manufacturing a vapor chamber structure, comprising:

providing a casing composed of an upper casing and a lower casing;

pre-fabricating a wick layer outside of and free from the casing, and subsequently affixing the wick layer to the interior of the casing;

assembling the upper casing and the lower casing together to form a chamber;

pumping away air from the chamber; and

filling a working fluid into the chamber and sealing the casing.

74. The method for manufacturing a vapor chamber structure as claimed in claim 73, wherein a plurality of structures are arranged between the upper casing and the lower casing and comprise at least one backflow accelerating body, or at least one channel, or at least one micro-channel, or a multi-layered wick layer.

75. The method for manufacturing a pre-fabricated improved wick outside and apart from the vapor chamber, such wick layer formed by a plurality of wick elements adjoined to each other such that they create a continuous, porous layer.

76. The method as claimed in claim 75 wherein the joining method for the wick elements is by a high temperature process over 350 degrees Celsius.

77. The method as claimed in claim 76 wherein the joining method is chosen from sintering, diffusion bonding, copper-copper oxide eutectic bonding, or brazing.

78. The method as claimed in claim 75 wherein the method reduces the wick layer thickness in certain locations.

79. The method as claimed in claim 78 wherein wick elements are reduced in number or eliminated in those areas of reduced wick layer thickness.

80. The method as claimed in claim 79 wherein adjoined wick elements are compressed in those areas of reduced wick layer thickness.

81. The method as claimed in claim 75 wherein the method increases the wick layer thickness in certain locations.

82. The method as claimed in claim 81 wherein wick elements are increased in number in those areas of increased wick layer thickness.

83. The method as claimed in claim 75 wherein the method includes the addition of structure strengthening bodies to the wick layer in certain locations.

84. The method as claimed in claim 75 wherein the method includes the addition of backflow accelerating bodies to the wick layer in certain locations.

85. The method as claimed in claim 75 wherein the method includes bending or forming the wick layer in certain locations.

86. The method as claimed in claim 75 wherein the method includes the use of wick elements of different sizes or types.

87. The method as claimed in claim 86 wherein the method includes arranging certain of the wick elements by size or type within certain areas of the wick.

88. The method as claimed in claim 87 wherein the method arranges wick elements by size in the vertical direction with either the smallest elements on top or conversely with the largest elements on top to form a piece-wise continuous or continuous gradient of wick element sizes.

89. The method as claimed in claim 87 wherein the method arranges wick elements by size in the plan or horizontal direction from elements of smaller to larger size to form a piece-wise continuous or continuous gradient of wick element sizes.

90. The method as claimed in claim 87 wherein the method arranges wick elements of different sizes or types in multiple layers, with at least one layer of one size or type of wick element and another layer of a second size or type of wick element.

91. The method as claimed in claim 90 wherein the method arranges wick elements of different sizes or types in multiple layers, with at least one layer of one size or type of wick element and another layer of a second size or type of wick element, and also provides communication or a via in certain locations from a first wick layer to a third wick layer through an intervening second wick layer.

92. The method as claimed in claim 87 wherein the method arranges wick elements of different sizes or types such that one or more patches of a wick element of one size or type are arranged within a field of substantially a wick element of a second size or type.

93. The method as claimed in claim 92 wherein the method arranges wick elements of different sizes or types such that more than one patches of a wick element of one size or type are arranged within a field of substantially a wick element of a second size or type, and there is a communication between the wick elements of the first size or type.

94. The method as claimed in claim 93 wherein the method provides communication between patches by creating pathways between patches of the same wick element that forms the patches.

95. The method as claimed in claim 93 wherein the method provides communication between patches by using wick elements of a third type or by no wick elements at all to create the communication pathways, as distinguished from using the first wick elements or the second wick elements.

96. The method as claimed in claim 87 wherein the method arranges wick elements of different sizes or types both in multiple layers and with patches of wick elements of different sizes or types within a field comprised of wick elements of a different size or type within certain layers, and providing for communication between patches within layers horizontally and for communication between layers vertically, such method consisting of the structured arrangement of wick elements of different sizes or types in certain locations starting with a first layer and subsequently adding additional layers one atop the other with the structured arrangement of wick elements of different sizes or types in certain locations on each subsequent layer.