Thermal interface material structures for directing heat in three-dimensional space

Abstract

A thermal interface material (TIM) structure for directing heat in three-dimensional space includes a TIM sheet having a lower portion along a lower plane, a first lateral portion along a first lateral plane, a first upper portion along an upper plane, a first fold line between the lower portion and the first lateral portion that positions the first lateral portion substantially perpendicular to the lower portion, and a second fold line between the first lateral portion and the first upper portion that positions the first upper portion substantially perpendicular to the first lateral portion and substantially parallel to the lower portion.

Description

[Technical field]

[0001] The field of the invention is data processing, or more specifically, methods and systems for thermal interface material constructions for directing heat in three-dimensional space. [Background technology]

[0002] The development of the EDVAC computer system in 1948 is often referred to as the beginning of the computer age. Since that time, computer systems have evolved into extremely complex devices. Today's computers are much more sophisticated than early systems such as the EDVAC. A computer system typically includes a combination of hardware and software components, application programs, operating systems, processors, buses, memory, input / output devices, etc. As advances in semiconductor processing and computer architectures have enabled computers to become more and more powerful, more sophisticated computer software has evolved to take advantage of the higher performance of the hardware, resulting in today's computer systems that are much more powerful than those of just a few years ago.

[0003] These advances in computer systems have created a need for more efficient thermal management within these complex systems. To obtain the best performance from some components, particularly central processing units and image processing units, heat must be removed quickly and efficiently from these components and nearby areas. However, these components often generate less heat and are located near other components that also require fast and efficient heat removal. To further complicate things, different components may have different loading requirements in order to maintain operable temperatures. Summary of the Invention

[0004] A thermal interface material structure for directing heat in three-dimensional space can include a thermal interface material (TIM) sheet including a lower portion along a lower plane, a first lateral portion along a first lateral plane, a first upper portion along an upper plane, a first fold between the lower portion and the first lateral portion that positions the first lateral portion substantially perpendicular to the lower portion, and a second fold between the first lateral portion and the first upper portion that positions the first upper portion substantially perpendicular to the first lateral portion and substantially parallel to the lower portion.

[0005] Advantages provided by such embodiments of thermal interface material structures for directing heat in three-dimensional space include providing thermal interconnects between heat exchangers and / or heat spreader plates and components at various heights relative to the circuit board. Advantages further include providing thermal interconnects between components having various load requirements. The three-dimensional shape of the TIM sheet allows for precise placement and retention of the TIM during manufacturing. The larger surface area provides continuous heat transfer and spreading. The three-dimensional TIM sheet is highly compressible, highly conductive at smaller loads, and provides various gap-filling capabilities for small gaps. Finally, the TIM sheet is easily assembled, easily reworked, and easily rearranged. These advantages are obtained by using a single TIM sheet that is folded to provide a thermal interconnect between at least two planes in the system.

[0006] In one optional embodiment, the TIM sheet may further include a second lateral portion along the second lateral plane, a second upper portion along the upper plane, a third fold between the lower portion and the second lateral portion that positions the second lateral portion substantially perpendicular to the lower portion, and a fourth fold between the second lateral portion and the second upper portion that positions the second upper portion substantially perpendicular to the second lateral portion and substantially parallel to the lower portion, providing the advantage of providing an additional portion of the TIM sheet that extends the thermal interconnect into another portion of the upper plane.

[0007] In one optional embodiment, the thermal interface material structure for directing heat in three-dimensional space can further include a gap filler pad in thermal contact with the first upper portion, which provides the advantage of ensuring reliable thermal contact with elements above and below the upper portion of the TIM sheet, such as a heat spreader plate or a heat exchanger.

[0008] In one optional embodiment, the upper portion of the TIM sheet can include additional alternating folds or rolled upper portions that create adjacent layers of the TIM sheet, providing the advantage of additional gap filling for various types of gaps while maintaining a thermal interconnect with the TIM sheet.

[0009] A thermal interface material structure for directing heat in three-dimensional space can include a system including a circuit board having a first component having a first load requirement and a second component having a second load requirement, a heat exchanger, and a heat spreader plate in thermal contact with the first component, the heat spreader plate having a cavity exposing the second component, a thermal interface material (TIM) sheet having a lower portion positioned between and in thermal contact with the second component and the heat exchanger, a first upper portion positioned between and in thermal contact with the heat spreader plate, the heat exchanger, and the second component, and a first lateral portion connecting the lower portion to the first upper portion.

[0010] Advantages provided by such embodiments of thermal interface material structures for directing heat in three-dimensional space include providing thermal interconnects between components at various heights relative to the circuit board and the heat exchanger. Advantages further include providing thermal interconnects between components having different load requirements. These advantages are obtained by using a single TIM sheet that is folded to provide thermal interconnects between circuit board components, heat spreader plates, and heat exchangers that are in different planes within the system.

[0011] In one optional embodiment, the system includes a heat spreader plate positioned between and in thermal contact with the second component and the first upper portion, the heat spreader plate including a cavity exposing the first component, and the first side portion connecting the lower portion to the first upper portion through the cavity of the heat spreader plate, thereby providing an advantage of providing a heat spreading agent between the second component and the TIM sheet.

[0012] In one optional embodiment, the TIM sheet further comprises gap filler pads between and in thermal contact with the first upper portion and the heat exchanger, which provides the advantage of ensuring reliable thermal contact between the heat spreader plates above and below the upper portion of the TIM and the heat exchanger.

[0013] In one optional embodiment, the TIM sheet may further include a second upper portion positioned between and in thermal contact with the heat spreader plate and the heat exchanger, and a second lateral portion passing through the cavity in the heat spreader plate and connecting the lower portion to the second upper portion, providing the advantage of adding a portion of the TIM that extends the thermal interconnect to another portion of the upper plane between the heat spreader plate and the heat exchanger.

[0014] In an optional embodiment, the thermal interface material structure for directing heat in three-dimensional space can further include an upper portion with additional alternating folds or a rolled upper portion that creates adjacent layers of the TIM sheet, providing the advantage of additional gap filling for various types of gaps while maintaining a thermal interconnect with the TIM sheet.

[0015] A method for forming a thermal interface material structure for directing heat in three-dimensional space can include positioning a TIM sheet between an upper forming tool and a lower forming tool and pressing the upper forming tool against the lower forming tool to create a first fold and a second fold in the TIM sheet, the first fold being between a lower portion of the TIM sheet and a first side portion of the TIM sheet, the first fold positioning the first side portion of the TIM sheet substantially perpendicular to the lower portion of the TIM sheet, and the second fold being between the first side portion of the TIM sheet and a first upper portion of the TIM sheet, the second fold positioning the first upper portion of the TIM sheet substantially perpendicular to the first side portion of the TIM sheet and substantially parallel to the lower portion of the TIM sheet.

[0016] Advantages provided by such embodiments for forming a thermal interface material structure for directing heat in three-dimensional space include forming a three-dimensional TIM sheet that provides a thermal interconnect between a heat exchanger and / or heat spreader plate and components at various heights relative to a circuit board. Advantages further include forming a TIM sheet that provides a thermal interconnect between components having various loading requirements. These advantages are obtained by folding a single TIM sheet to provide a thermal interconnect between at least two planar surfaces in a system.

[0017] In an optional embodiment, the method for forming a thermal interface material structure for directing heat in three-dimensional space can further include pressing an upper forming tool against a lower forming tool to compress an upper portion of the TIM sheet without compressing a lower portion of the TIM sheet, which provides the advantage that a three-dimensional TIM sheet is formed without unnecessarily compressing and avoiding degradation of the lower portion that may be used to make thermal contact with components that generate more heat and have lower load requirements.

[0018] In one optional embodiment, pressing the upper forming tool against the lower forming tool further creates a third fold and a fourth fold in the TIM sheet, the third fold being between the lower portion of the TIM sheet and the second side portion of the TIM sheet, the third fold positioning the second side portion of the TIM sheet substantially perpendicular to the lower portion of the TIM sheet, and the fourth fold being between the second side portion of the TIM sheet and the second upper portion of the TIM sheet, the fourth fold positioning the second upper portion of the TIM sheet substantially perpendicular to the second side portion of the TIM sheet and substantially parallel to the lower portion of the TIM sheet, providing the advantage of adding a portion of the TIM sheet that extends the thermal interconnect into another portion of the upper plane.

[0019] In one optional embodiment, pressing the upper forming tool against the lower forming tool creates an adjacent layer of the TIM sheet adjacent and substantially parallel to the first upper portion or creates additional folds that coil the first upper portion, providing the advantage of additional gap filling for various types of gaps while maintaining a thermal interconnect with the TIM sheet.

[0020] The above and other objects, features, and advantages of the present invention will become apparent from the following more particular description of illustrative embodiments of the invention, as illustrated in the accompanying drawings in which like reference numerals generally represent like parts of the illustrative embodiments of the invention. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 illustrates an exemplary thermal interface material (TIM) sheet for directing heat in three-dimensional space, in accordance with an embodiment of the present invention. [Diagram 2] FIG. 1 illustrates an exemplary system comprising a TIM structure for directing heat in three-dimensional space, in accordance with an embodiment of the present invention. [Diagram 3] FIG. 1 illustrates an exemplary system comprising a TIM structure for directing heat in three-dimensional space, in accordance with an embodiment of the present invention. [Figure 4] 1 illustrates an exemplary TIM structure for directing heat in three-dimensional space, in accordance with an embodiment of the present invention. [Diagram 5] FIG. 1 illustrates an exemplary TIM sheet for directing heat in three-dimensional space, in accordance with an embodiment of the present invention. [Figure 6] FIG. 1 is a diagram of an exemplary system for creating a TIM sheet for directing heat in three-dimensional space, in accordance with an embodiment of the present invention. [Figure 7] FIG. 1 is a diagram of an exemplary system for creating a TIM sheet for directing heat in three-dimensional space, in accordance with an embodiment of the present invention. [Figure 8]1 is a flow chart illustrating an exemplary method for creating a thermal interface material structure for directing heat in three-dimensional space, in accordance with an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] A diagram illustrating an exemplary thermal interface material (TIM) sheet for directing heat in three-dimensional space, according to an embodiment of the present invention, is shown in Figure 1. As shown in Figure 1, the TIM sheet (100) includes a lower portion (102), two upper portions, upper portion A (104A) and upper portion B (104B), and two side portions, side portion A (106A) and side portion B (106B).

[0023] The TIM sheet (100) is a single continuous sheet of thermally conductive material. The TIM sheet may be a single material type, such as a graphite TIM sheet. Alternatively, the TIM sheet may be a composite material, such as a particle-filled silicone or fiber-filled silicone and / or acrylate TIM sheet. Additionally, the TIM sheet may be a cured or partially cured elastomeric matrix, such as silicone, filled with any number of thermally conductive materials. Such thermally conductive materials may include ceramic particles, such as, but not limited to, aluminum nitride, boron nitride, zinc oxide, or aluminum oxide. Such thermally conductive materials may also include metal particles or metal plated particles, such as, but not limited to, aluminum, copper, silver, gold, or tungsten, and particulate fillers with various carbon morphologies, including, for example, graphite flakes, carbon fibers, carbon nanotubes, or crystalline diamond particles. Non-silicone elastomeric matrices with the various fillers listed above may also be used in the TIM pad. The folded TIM sheet can be made from a polymer phase change material matrix filled with the above sets of particulate materials. The folded TIM sheet can also be made from metals such as, but not limited to, indium or aluminum clad indium. Additionally, the TIM sheet can be compressible in that the thickness of the TIM sheet can be reduced when pressure is applied to the TIM sheet.

[0024] As shown in FIG. 1, the lower portion (102) of the TIM sheet is aligned along a lower plane. The side portions (side portion A (106A), side portion B (106B)) are aligned along two lateral planes that are substantially parallel to each other. The folds between the lower portion (102) and the side portions (side portion A (106A), side portion B (106B)) position the side portions (side portion A (106A), side portion B (106B)) substantially perpendicular to the lower portion (102) and substantially parallel to the other side portion. The upper portions (upper portion A (104A), upper portion B (104B)) are aligned along an upper plane that is substantially parallel to the lower plane. The folds between the side portions (side portion A (106A), side portion B (106B)) and the upper portion (upper portion A (104A), upper portion B (104B)) position the upper portion (upper portion A (104A), upper portion B (104B)) substantially perpendicular to the side portions (side portion A (106A), side portion B (106B)) and substantially parallel to the lower portion (102).

[0025] The embodiment including a lower portion (102), a single side portion (e.g., side portion (106A)), and a single upper portion (e.g., upper portion A (104A)) has the advantage of providing a thermal interconnect between components on different planes by using a single TIM sheet to accommodate different operating heights of the hardware while reducing formation complexity since only two folds of TIM material are required. The embodiment including a lower portion (102), two upper portions (upper portion A (104A), upper portion B (104B)), and two side portions (side portion A (106A), side portion B (106B)) has the advantage of providing a larger thermal interconnect between components on multiple different planes by using a single TIM sheet to accommodate different operating heights of the hardware.

[0026] Although the TIM sheet (100) in Figure 1 is shown with four folds, each at a 90 degree angle, other embodiments include a different number of folds at various angles, which can also provide a TIM sheet that thermally couples two layers in three-dimensional space.

[0027] FIG. 2 depicts an exemplary system with a TIM structure for directing heat in three-dimensional space, according to an embodiment of the present invention. The exemplary system includes a heat exchanger (200), a TIM sheet (100), a heat spreader plate (202), and a circuit board (204). The heat spreader plate (202) includes a heat spreader plate cavity (208). The circuit board (204) includes multiple components below the heat spreader plate (202), including a processing unit (206) that is visible through the heat spreader plate cavity (208). Although depicted as being generally surrounded by the heat spreader plate (202), the heat spreader plate cavity (208) may be only partially surrounded by the heat spreader plate (202).

[0028] A circuit board (204) is a collection of electronic components, typically connected to layers of conductive and non-conductive substrates. Some of the components on the circuit board (204) require or benefit from thermal contact with a heat dissipation mechanism. Figure 2 depicts a heat spreader plate (202) on top of the circuit board, which is in thermal contact with multiple components on the circuit board (204) either directly or through a thermal interface material (TIM) (e.g., TIM sheet, TIM grease, etc.) that is not visible in Figure 2.

[0029] The heat spreader plate (202) is a plate of thermally conductive material that transfers heat from components on the circuit board (204) thermally connected to the heat spreader plate (202) toward the heat exchanger (200). The heat exchanger (200) is a mechanism, such as a cooling plate, that transfers and dissipates heat from the heat spreader plate (202) and the processing unit (206) to a fluid medium. The heat exchanger (200) can be liquid or air cooled. As shown in FIG. 2, the heat exchanger can be used in combination with the heat spreader plate (202). Alternatively, the heat exchanger (200) can be used without the heat spreader plate, with a TIM sheet (100) disposed between the heat exchanger (200) and the components of the circuit board (204).

[0030] Various components on the circuit board (204), such as the processing unit (206), may have different heat removal and load requirements. Specifically, the processing unit (206) may generate more heat than other components on the circuit board (not shown) and may have less load requirements than other components on the circuit board (204). The cavities in the heat spreader plate (202) allow the heat exchanger (200) to have more direct access to the processing unit (206) to more effectively remove heat from the processing unit (206). The cavities in the heat spreader plate (202) also allow the load on the processing unit (206) to be different than the loads applied to other components in thermal contact with the heat spreader.

[0031] To accommodate the aforementioned configuration of the circuit board (204), heat spreader plate (202), and heat exchanger (200), the TIM sheet (100) provides a thermal interconnect between the processing unit (206), the heat spreader plate (202), and the heat exchanger (200). The bottom of the lower portion of the TIM sheet (100) is in thermal contact with the processing unit (206). The top of the lower portion of the TIM sheet (100) is in thermal contact with the heat exchanger (200). The bottom of the upper portion of the TIM sheet (100) is in thermal contact with the heat spreader plate (202). Finally, the top of the upper portion of the TIM sheet (100) is in thermal contact with the heat exchanger (200) (optionally with a gap filler as shown in Figures 4 and 5 and discussed in the associated text). The side portions of the TIM sheet (100) provide thermal interconnections between each other portion of the TIM sheet (100) and elements in thermal contact with those portions of the TIM sheet (100).

[0032] Load requirements for a component, such as the processing unit (206), refer to limits (upper or lower) on the amount of pressure that can be applied to the component for optimal functionality or to avoid negative effects on functionality. Two components on the circuit board (204) may have different load requirements, so that a single element may not be able to provide that load. As shown in FIG. 2, some components of the circuit board (204) are loaded by the heat spreader plate (202), and the processing unit (206) is loaded by the heat exchanger (200) and the TIM sheet (100). This configuration allows different load levels to be applied to the various components on the circuit board (204).

[0033] A diagram illustrating an exemplary system with a TIM structure for directing heat in three-dimensional space, according to an embodiment of the present invention, is shown in Figure 3. Specifically, Figure 3 illustrates the fully assembled elements of Figure 2 with a TIM sheet (100) disposed between a heat exchanger (200) and a heat spreader plate (202) attached to a circuit board (204). The heat exchanger (200) is in thermal contact with a processing unit (206) through the TIM sheet (100) and through the heat spreader plate cavity (208).

[0034] A diagram depicting an exemplary TIM structure for directing heat in three-dimensional space in accordance with an embodiment of the present invention is shown in Figure 4. As shown in Figure 4, the TIM structure (400) includes a lower portion (102), two upper portions (upper portion A (104A), upper portion B (104B)), and two side portions (side portion A (106A), side portion B (106B)) of a TIM sheet.

[0035] The TIM structure (400) of FIG. 4 also includes two gap filler pads (Gap Filler Pad A (402A) and Gap Filler Pad B (402B)). The gap filler pads (Gap Filler Pad A (402A) and Gap Filler Pad B (402B)) are in thermal contact with a first upper portion (Upper Portion A (104A) and Upper Portion B (104B)) of the TIM sheet. The gap filler pads (Gap Filler Pad A (402A) and Gap Filler Pad B (402B)) are positioned between the TIM sheet and a heat exchanger such as a cooling plate. The gap filler pads (Gap Filler Pad A (402A), Gap Filler Pad B (402B)) can be used to create proper thermal contact between the upper portion of the TIM sheet (Upper Part A (104A), Upper Part B (104B)) and the heat exchanger. The embodiment of the TIM structure including the gap filler pads (Gap Filler Pad A (402A), Gap Filler Pad B (402B)) has the advantage that an adjustable thermal contact point between the upper portion of the TIM sheet (Upper Part A (104A), Upper Part B (104B)) and the heat exchanger is provided. The gap filler pads (Gap Filler Pad A (402A), Gap Filler Pad B (402B)) may be made of a variety of different thermally conductive materials.

[0036] FIG. 5 depicts an exemplary TIM sheet for directing heat in three-dimensional space, according to an embodiment of the present invention. As shown in FIG. 5, the TIM sheet (100) includes a lower portion (102), two upper portions (upper portion A (104A), upper portion B (104B)), and two side portions (side portion A (106A), side portion B (106B)). As shown in FIG. 5, the upper portions (upper portion A (104A), upper portion B (104B)) of the TIM sheet (500) include alternating additional folds that create a contiguous layer of the TIM sheet (500) on the upper portions (upper portion A (104A), upper portion B (104B)).

[0037] The embodiment including alternating folds creating adjacent layers of the TIM sheet has the advantage of providing adjustable thermal contact points between the upper portions of the TIM sheet (upper portion A (104A), upper portion B (104B)) and the heat exchanger. Additionally, the alternating folds of the TIM sheet themselves are used as gap fillers to provide a continuous thermal interconnect that efficiently transfers heat from the upper portions of the TIM sheet (upper portion A (104A), upper portion B (104B)) to the heat exchanger.

[0038] In a similar embodiment, one or more of the upper portions of the TIM sheet (upper portion A (104A), upper portion B (104B)) may be rolled. The upper portions (upper portion A (104A), upper portion B (104B)) may be rolled into a spiral cylinder about an axis. The embodiment including a rolled upper portion has the advantage that it fills any cylindrical gaps that may exist between the heat spreader plate, the upper portions of the TIM sheet, and the heat exchanger.

[0039] An exemplary system for creating a TIM sheet for directing heat in three-dimensional space is shown in Figure 6, according to an embodiment of the present invention. As shown in Figure 6, the system includes an upper forming tool (602) and a lower forming tool (604), with the TIM sheet (100) disposed between the upper forming tool (602) and the lower forming tool (604). Figure 6 depicts the forming tools and the TIM sheet (100) prior to engagement and forming.

[0040] FIG. 7 illustrates an exemplary system for creating a TIM sheet for directing heat in three-dimensional space, according to an embodiment of the present invention. As shown in FIG. 7, the system includes an upper forming tool (602) and a lower forming tool (604), and the TIM sheet (100) is pressed between the upper forming tool (602) and the lower forming tool (604). FIG. 7 illustrates the forming tools and the TIM sheet (100) after engagement and forming. Specifically, pressing the upper forming tool (602) and the lower forming tool (604) creates creases between the TIM lower portion (102) and the TIM side portions (side portion A (106A), side portion B (106B)) and between the TIM side portions (side portion A (106A), side portion B (106B)) and the TIM upper portion (upper portion A (104A), upper portion B (104B)).

[0041] As shown in Figure 6, pressing the upper forming tool against the lower forming tool compresses the upper portion of the TIM sheet without compressing the lower portion of the TIM sheet. The embodiment of pressing the upper forming tool against the lower forming tool and compressing the upper portion of the TIM sheet without compressing the lower portion of the TIM sheet has the advantage that the compressible integrity of the lower portion of the TIM sheet is maintained during formation of the three-dimensional TIM sheet. Maintaining the integrity of the lower portion of the TIM sheet during formation may result in better performance of the lower portion of the TIM sheet when in thermal contact with a component that produces large amounts of heat.

[0042] The modified forming tool may be used to create adjacent layers of the TIM sheet adjacent and substantially parallel to the upper portion of the TIM sheet (as depicted in FIG. 5). The modified forming tool may also be used to coil the first upper portion (as described in the discussion of FIG. 5).

[0043] Prior to pressing the upper forming tool against the lower forming tool, the TIM sheet may be scored along the expected fold line. Specifically, the TIM sheet may be scored between the lower portion of the TIM sheet and the first side portion of the TIM sheet, and between the first side portion of the TIM sheet and the first upper portion of the TIM sheet. Score the TIM sheet prior to folding has the advantage that the location of the creases in the TIM sheet is precisely guided, improving the accuracy of forming the TIM sheet.

[0044] For further explanation, FIG. 8 depicts a flowchart illustrating another exemplary method for forming a thermal interface material structure for directing heat in three-dimensional space in accordance with an embodiment of the present invention, the method including a forming tool (800) that positions a thermal interface material (TIM) sheet between an upper forming tool and a lower forming tool (802) and presses the upper forming tool against the lower forming tool to create a first fold and a second fold in the TIM sheet (804), the first fold being between a lower portion of the TIM sheet and a first side portion of the TIM sheet, the first fold positioning the first side portion of the TIM sheet substantially perpendicular to the lower portion of the TIM sheet, and the second fold being between a first side portion of the TIM sheet and a first upper portion of the TIM sheet, the second fold positioning the first upper portion of the TIM sheet substantially perpendicular to the first side portion of the TIM sheet and substantially parallel to the lower portion of the TIM sheet.

[0045] By pressing the upper forming tool against the lower forming tool, the upper portion of the TIM sheet can be compressed without compressing the lower portion of the TIM sheet, which has the advantage that the compressible integrity of the lower portion of the TIM sheet is maintained during formation of the three-dimensional TIM sheet.

[0046] It will be understood from the foregoing description that modifications and changes may be made to the various embodiments of the present invention without departing from the true spirit thereof. The description herein is for illustrative purposes only and should not be construed in a limiting sense. The scope of the present invention is limited only by the language of the appended claims.

Claims

1. A system comprising: a circuit board including a first component having a first limit on applied pressure and a second component having a second limit on applied pressure; A heat exchanger; A thermal interface material (TIM) sheet comprising: a lower portion positioned between and in thermal contact with the first component and the heat exchanger; a first upper portion positioned between and in thermal contact with the heat exchanger and at least a portion of the second component; a first lateral portion connecting said lower portion to said first upper portion; a first fold between the lower portion and the first side portion; and a second fold between the first side portion and the first upper portion the first fold line positions the lower portion and the first side portion such that the first side portion is generally perpendicular to the lower portion, and the second fold line positions the first side portion and the first upper portion such that the first upper portion is generally perpendicular to the first side portion and generally parallel to the lower portion; a heat spreader plate positioned between and in thermal contact with the at least a portion of the second component and the first upper portion; the heat spreader plate comprising a cavity exposing the first component, and the first side portion connecting the lower portion to the first upper portion through the cavity of the heat spreader plate.

2. 1. A system comprising: a circuit board including a first component having a first limit on applied pressure and a second component having a second limit on applied pressure; A heat exchanger; A thermal interface material (TIM) sheet comprising: a lower portion positioned between and in thermal contact with the first component and the heat exchanger; a first upper portion positioned between and in thermal contact with the heat exchanger and the second component; and a first side portion connecting said lower portion to said first upper portion; the thermal interface material (TIM) sheet comprising: a heat spreader plate positioned between and in thermal contact with the second component and the first upper portion; wherein the heat spreader plate includes a cavity exposing the first component, and the first side portion connects the lower portion to the first upper portion through the cavity of the heat spreader plate.

3. A method comprising: placing a thermal interface material (TIM) sheet between an upper forming tool and a lower forming tool; pressing the upper forming tool against the lower forming tool to create a first crease and a second crease in the TIM sheet; Including, the first fold line is between a lower portion of the TIM sheet and a first side portion of the TIM sheet, the first fold line positions the lower portion and the first side portion such that the first side portion of the TIM sheet is substantially perpendicular to the lower portion of the TIM sheet; the second fold line is between the first side portion of the TIM sheet and the first upper portion of the TIM sheet, the second fold line positions the first side portion and the first upper portion such that the first upper portion of the TIM sheet is generally perpendicular to the first side portion of the TIM sheet and generally parallel to the lower portion of the TIM sheet; The method, wherein the resulting TIM sheet is configured to be repositionable, and pressing the upper forming tool against the lower forming tool includes partially pressing the TIM sheet with the upper forming tool and the lower forming tool leaving a space between the lower forming tool and the lower portion of the TIM sheet to compress the first upper portion of the TIM sheet without compressing the lower portion of the TIM sheet.

4. 1. A method comprising: placing a thermal interface material (TIM) sheet between an upper forming tool and a lower forming tool; pressing the upper forming tool against the lower forming tool to create a first crease and a second crease in the TIM sheet; Including, the first fold line is between a lower portion of the TIM sheet and a first side portion of the TIM sheet, the first fold line positions the first side portion of the TIM sheet substantially perpendicular to the lower portion of the TIM sheet; the second fold is between the first side portion of the TIM sheet and a first upper portion of the TIM sheet, the second fold being positioned with the first upper portion of the TIM sheet generally perpendicular to the first side portion of the TIM sheet and generally parallel to the lower portion of the TIM sheet, and pressing the upper forming tool against the lower forming tool includes partially pressing the TIM sheet with the upper forming tool and the lower forming tool leaving a space between the lower forming tool and the lower portion of the TIM sheet to compress the first upper portion of the TIM sheet without compressing the lower portion of the TIM sheet.

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