Method and system for manufacturing a MEMS-based cooling system

Abstract

A method for providing a cooling system is described. The method includes providing a plurality of sheets. Each sheet includes at least one structure for a level in each of a plurality of cooling cells. A particular level of each cooling cell includes a cooling element having a first side and a second side. The cooling element is configured to undergo a vibrational motion to drive fluid from the first side to the second side. The method also includes aligning the sheets, attaching the sheets to form a laminate including the cooling cells, and separating the laminate into segments. Each segment includes at least one cooling cell.

Description

[0001] Cross-references to related applications This application claims priority to U.S. Provisional Patent Application No. 63 / 079,460, filed September 16, 2020, entitled “METHOD AND SYSTEM FOR FABRICATING MEMS-BASED COOLING SYSTEMS”, which is incorporated herein by reference for all purposes. Background Technology

[0002] As computing devices increase in speed and computing power, the heat generated by them also increases. Various mechanisms have been proposed to address heat generation. Active cooling devices (such as fans) can be used to drive air through larger computing devices (such as laptops or desktop computers). Passive cooling devices (such as heat sinks) can be used in smaller mobile computing devices (such as smartphones, virtual reality devices, and tablets). However, such active and passive cooling devices may not adequately cool both mobile devices (such as smartphones) and larger devices (such as laptops and desktop computers). Therefore, additional cooling solutions for computing devices are desired. Attached Figure Description

[0003] Various embodiments of the invention are disclosed in the following detailed description and accompanying drawings.

[0004] Figure 1A-1F An embodiment of an active cooling system including a cooling element anchored at the center is described.

[0005] Figure 2A-2B An embodiment of a cooling element that can be used in an active cooling system including a centrally anchored cooling element is described.

[0006] Figures 3A-3B An embodiment of a cooling element that can be used in an active cooling system including a centrally anchored cooling element is described.

[0007] Figures 4A-4B An embodiment of an active cooling system including a cooling element anchored at the center is described.

[0008] Figures 5A-5E An embodiment of an active cooling system formed in a tile is described.

[0009] Figure 6 This is a flowchart depicting an embodiment of a method for providing (multiple) cooling systems using sheet level fabrication.

[0010] Figures 7A-7GAn embodiment of a lamination cooling system during manufacturing is described.

[0011] Figures 8A-8C These are diagrams depicting embodiments of laminated cooling systems 800A, 800B, and 800C, illustrating manufacturing processes using sheet-layer fabrication.

[0012] Figure 9 This is a diagram depicting an embodiment of a cooling system used during manufacturing and in which welded parts are employed.

[0013] Figure 10 This is a flowchart depicting an embodiment of a method for providing (multiple) cooling systems using sheet layer manufacturing.

[0014] Figure 11A-11D An embodiment of a lamination cooling system during manufacturing is described.

[0015] Figure 12A-12D An embodiment of a cooling element formed using sheet layer manufacturing is depicted. Detailed Implementation

[0016] This invention can be embodied in a variety of ways, including as a process; an apparatus; a system; a composition of matter; a computer program product embodied on a computer-readable storage medium; and / or a processor, such as a processor configured to execute instructions stored in and / or provided thereto in memory coupled to and / or to a processor. In this specification, these embodiments or any other forms in which the invention may take are referred to as techniques. Generally, within the scope of this invention, the order of steps of the disclosed process may be varied. Unless otherwise stated, components such as processors or memory described as configured to perform a task may be implemented as general-purpose components temporarily configured to perform the task at a given time or manufactured as special-purpose components to perform that task. As used herein, the term "processor" means one or more means, circuits, and / or processing cores configured to process data such as computer program instructions.

[0017] The following provides a detailed description of one or more embodiments of the invention, along with accompanying drawings illustrating the principles of the invention. The invention has been described in conjunction with such embodiments, but is not limited to any particular embodiment. The scope of the invention is limited only by the claims, and the invention covers numerous alternatives, modifications, and equivalents. Numerous specific details are set forth in the following description to provide a thorough understanding of the invention. These details are provided for illustrative purposes, and the invention may be practiced without some or all of these specific details. For clarity, technical materials known in the art related to the invention have not been described in detail so as not to unnecessarily obscure the invention.

[0018] As semiconductor devices become increasingly powerful, the heat generated during operation also increases. For example, processors used in mobile devices such as smartphones, tablets, laptops, and virtual reality devices can operate at high clock speeds, but generate a significant amount of heat. Due to this heat, the processor may only run at full speed for a relatively short period. After this period, throttling occurs (e.g., the processor clock speed is slowed down). While throttling reduces heat generation, it also negatively impacts processor speed and, consequently, the performance of the devices using the processor. This problem is expected to worsen as technology advances towards 5G and beyond.

[0019] Larger devices, such as laptops or desktop computers, include electric fans with rotating blades. These fans are powered in response to rising temperatures in the internal components. The fan drives air through the larger device to cool the internal components. However, such fans are often too large for mobile devices like smartphones or thinner devices like tablets. Fans can also be limited in effectiveness due to the boundary layer of air present at the surface of the components, providing limited airflow velocity across the hot surfaces to be cooled, and may generate excessive noise. Passive cooling solutions may include components such as radiators and heat pipes or vapor chambers to transfer heat to heat exchangers. While radiators mitigate temperature rises at hot spots to some extent, they may not adequately address the heat generated in current and future devices. Similarly, heat pipes or vapor chambers may not provide sufficient heat transfer to remove excess generated heat.

[0020] The diverse configurations of computing devices further complicate thermal management. For example, computing devices such as laptops are often open to the external environment, while other computing devices such as smartphones are largely closed. Therefore, active thermal management solutions (such as fans) for open devices may not be suitable for closed devices. A fan that drives heated fluid from the inside of the computing device to the external environment may be too large for a closed computing device such as a smartphone and may provide limited fluid flow. Furthermore, even if a fan could be incorporated into a closed computing device, there is no outlet for the heated fluid. Therefore, thermal management provided by such an open device structure may have limited effectiveness. Even for open computing devices, the location of the inlet and / or outlet can be configured differently for different devices. For example, in a laptop, it might be desirable to have the outlet for the fan-driven fluid flow away from the user's hand or located within other structural placements within the outflow of heated fluid. Such a configuration not only prevents user discomfort but also allows the fan to provide the desired cooling. Other mobile devices with different configurations may require different inlet and / or outlet configurations, which could reduce the effectiveness of such a thermal management system and may hinder its use. Therefore, mechanisms for improving cooling in computing devices are desired.

[0021] A method for providing a cooling system is described. The method includes providing a plurality of sheets. Each sheet includes at least one structure for a layer in each of a plurality of cooling cells. A particular layer in each cooling cell includes a cooling element having a first side and a second side. The cooling element is configured to undergo vibratory motion to drive fluid from the first side to the second side. The method also includes aligning the sheets, attaching the sheets to form a laminate including cooling cells, and separating the laminate into segments. Each segment includes at least one cooling cell.

[0022] The sheet material may include an orifice plate sheet, an active element sheet, and a top plate sheet. The orifice plate sheet includes orifices. The active element sheet includes cooling elements for each cooling cell. The cooling elements have a central region and a periphery. The top plate sheet includes at least one vent for each of the cooling cells. In some such embodiments, alignment includes positioning the active element sheet between the top plate sheet and the orifice plate sheet. Attachment sheets may include attachment sheets such that the active element sheet is attached to the orifice plate sheet, the frame sheet is attached to the active element sheet, and the top plate sheet is attached to the frame sheet. A frame sheet may also be provided. A portion of the frame sheet forms a cell wall for each cooling cell.

[0023] In some embodiments, providing the active element sheet further includes selectively etching a substrate to provide multiple regions having multiple heights. Additionally, a piezoelectric layer is provided on a portion of the substrate. In some such embodiments, providing the active element sheet further includes providing an insulating barrier on a steel substrate and providing a bottom electrode on the insulating barrier. The piezoelectric layer is located on the bottom electrode. The method may also include connecting the bottom electrode to the substrate. Connecting the bottom electrode may include providing a bridge between the bottom electrode and the substrate, or providing vias(s) in the insulating barrier and providing vias(s) in the vias(s) prior to providing the bottom electrode. The substrate may include one or more of steel (e.g., stainless steel), Al (e.g., Al alloys), and / or Ti (e.g., Ti alloys such as Ti6Al-4V), or materials thereof. As part of providing the active element sheet, a support structure for cooling elements may be defined from a portion of the active element sheet.

[0024] A cooling system is also described. The cooling system includes: a laminated cooling cell comprising a plurality of sheets. Each sheet includes at least one structure for a hierarchy within the laminated cooling cell. An active element sheet includes a cooling element having a first side and a second side. The cooling element is configured to undergo vibratory motion to drive fluid from the first side to the second side. The sheets may further include an orifice plate sheet and a top plate sheet. The orifice plate sheet includes orifices. The top plate sheet has at least one vent therein. The active element sheet is located between the orifice plate sheet and the top plate sheet. The cooling element has a central region and a periphery configured to undergo vibratory motion. In some embodiments, the active element sheet further includes a support structure at the central region of the cooling element. The active element sheet is coupled to the orifice plate sheet by the support structure. In some embodiments, the active element sheet includes a piezoelectric layer. In such embodiments, the cooling element includes a substrate, an insulating barrier on the substrate, a bottom electrode on the insulating barrier, and an electrical connector between the bottom electrode and a stainless steel substrate. The piezoelectric layer is located on the bottom electrode. The sheet may further include a frame sheet. A portion of the frame sheet forms the cell wall for the laminated cooling unit. The frame sheet may be located between the active element sheet and the top plate sheet.

[0025] A cooling system comprising multiple laminated cooling cells is described. Each laminated cooling cell comprises multiple sheets. Each sheet includes at least one structure for a layer within the laminated cooling cell. The sheets further comprise an orifice plate sheet, an active element sheet, and a top plate sheet. The orifice plate sheet has multiple orifices therein for each cooling cell. The active element sheet includes a cooling element for each laminated cooling cell. The cooling element has a first side and a second side. The cooling element is configured to undergo vibratory motion to drive fluid from the first side to the second side. In some embodiments, the cooling element has a central region and at least one cantilever. The cantilever(s) undergo vibratory motion. The active element sheet may also include a support structure for the cooling element. The support structure is located at the central portion of the cooling element and is coupled to the orifice plate. The top plate sheet has at least one vent therein for each of the laminated cooling cells. The active element sheet is located between the orifice plate sheet and the top plate sheet. The sheets may further include a frame sheet. A portion of the frame sheet forms a cell wall for each of the laminated cooling cells. In some embodiments, the frame sheet is located between the active element sheet and the top plate sheet.

[0026] Figure 1A-1F This is a diagram depicting an exemplary embodiment of an active cooling system 100 that can be used with the heat-generating structure 102 and includes a centrally anchored cooling element 120 or 120'. The cooling element 120... Figure 1A-1E As shown, and the cooling element 120' is in Figure 1F As shown in the figure. For clarity, only certain components are shown. Figure 1A-1F Not drawn to scale. Although shown as symmetrical, the cooling system 100 is not necessarily symmetrical.

[0027] Cooling system 100 includes a top plate 110 having vents 112 therein, a cooling element 120, an orifice plate 130 having openings 132 therein, a support structure (or “anchor”) 160, and a top chamber 140 and a bottom chamber 150 (collectively referred to as top chamber 140 / bottom chamber 150) formed therein. Cooling element 120 is supported by anchor 160 at its central region. The portion closer to the periphery of the cooling element and the region including it (e.g., end 121) vibrates upon actuation. In some embodiments, end 121 of cooling element 120 includes the peripheral portion furthest from anchor 160 and experiences the greatest deflection during actuation of cooling element 120. For clarity, in Figure 1A The only end 121 of the cooling element 120 is marked in the middle.

[0028] Figure 1A The cooling system 100 is depicted in a neutral position. Therefore, the cooling element 120 is shown as substantially flat. For in-phase operation, the cooling element 120 is driven to... Figure 1B and Figure 1C The system vibrates between the locations shown. This vibrational motion draws fluid (e.g., air) into the vent 112 at high speed and / or high flow rate, through the top chamber 140 and the bottom chamber 150, and out of the orifice 132. For example, the fluid impacting the heat-generating structure 102 may be at a speed of at least thirty meters per second. In some embodiments, the fluid is driven toward the heat-generating structure 102 by the cooling element 120 at a speed of at least forty-five meters per second. In some embodiments, the fluid is driven toward the heat-generating structure 102 by the cooling element 120 at a speed of at least sixty meters per second. Other speeds are also possible in some embodiments. The cooling system 100 is also configured such that little or no fluid is drawn back into the top chamber 140 / bottom chamber 150 by the vibrational motion of the cooling element 120 through the orifice 132.

[0029] The heat-generating structure 102 is expected to be cooled by the cooling system 100. In some embodiments, the heat-generating structure 102 generates heat. For example, the heat-generating structure may be an integrated circuit. In some embodiments, the heat-generating structure 102 is expected to be cooled but not generate heat itself. The heat-generating structure 102 may conduct heat (e.g., from a nearby object that generates heat). For example, the heat-generating structure 102 may be a heat sink or a vapor chamber. Thus, the heat-generating structure 102 may include semiconductor components, including individual integrated circuit components such as processors, multiple other integrated circuits and / or multiple chip packages; multiple sensors; multiple optical devices; one or more batteries; multiple other components of electronic devices such as computing devices; heat sinks; heat pipes; multiple other electronic components and / or multiple other devices that are expected to be cooled. In some embodiments, the heat-generating structure 102 may be a thermally conductive portion of a module comprising the cooling system 100. For example, the cooling system 100 may be attached to the heat-generating structure 102, which may be coupled to other heat sinks, vapor chambers, integrated circuits, or other individual structures that are expected to be cooled.

[0030] Devices in which the cooling system 100 is intended to be used may also have limited space to house the cooling system. For example, the cooling system 100 may be used in a computing device. Such computing devices may include, but are not limited to, smartphones, tablets, laptops, tablets, 2-in-1 laptops, handheld gaming systems, digital cameras, virtual reality headsets, augmented reality headsets, mixed reality headsets, and other thinner devices. The cooling system 100 may be a microelectromechanical system (MEMS) cooling system capable of being located within a mobile computing device and / or other device having limited space in at least one dimension. For example, the total height of the cooling system 100 (from the top of the heat-generating structure 102 to the top of the top plate 110) may be less than 2 mm. In some embodiments, the total height of the cooling system 100 may not exceed 1.5 mm. In some embodiments, the total height may not exceed 1.1 mm. In some embodiments, the total height may not exceed 1 mm. In some embodiments, the total height may not exceed 250 micrometers. Similarly, the distance y between the bottom of the perforated plate 130 and the top of the heat-generating structure 102 may be small. In some embodiments, y is at least 200 micrometers and not more than 1.2 mm. In some embodiments, y is at least 500 micrometers and no more than 1 millimeter. In some embodiments, y is at least 200 micrometers and no more than 300 micrometers. Therefore, the cooling system 100 can be used in computing devices and / or other devices with limited space in at least one dimension. However, this does not preclude the use of the cooling system 100 in devices with less space constraints and / or for purposes other than cooling. Although one cooling system 100 (e.g., a cooling cell) is shown, multiple cooling systems 100 can be used in conjunction with the heat-generating structure 102. For example, a one-dimensional or two-dimensional array of cooling cells can be utilized.

[0031] The cooling system 100 is in fluid communication with the heat-generating structure 102 for cooling. The fluid may be a gas or a liquid. For example, the fluid may be air. In some embodiments, the fluid includes fluid from outside the device where the cooling system 100 is located (e.g., provided through an external vent in the device). In some embodiments, the fluid circulates within the device where the cooling system is located (e.g., in a closed device).

[0032] The cooling element 120 can be considered as dividing the interior of the active cooling system 100 into a top chamber 140 and a bottom chamber 150. The top chamber 140 is formed by the cooling element 120, sides, and a top plate 110. The bottom chamber 150 is formed by a perforated plate 130, sides, the cooling element 120, and anchors 160. The top chamber 140 and the bottom chamber 150 are connected at the periphery of the cooling element 120 and together form the top chamber 140 / bottom chamber 150 (e.g., the interior chamber of the cooling system 100).

[0033] The size and configuration of the top chamber 140 may depend on the size of the individual cell (cooling system 100), the frequency of movement and operation of the cooling element 120. The top chamber 140 has a height h1. The height of the top chamber 140 may be selected to provide sufficient pressure to drive fluid at a desired flow rate and / or velocity to the bottom chamber 150 and through the orifice 132. The top chamber 140 is also high enough that the cooling element 120 does not contact the top plate 110 when actuated. In some embodiments, the height of the top chamber 140 is at least fifty micrometers and no more than five hundred micrometers. In some embodiments, the top chamber 140 has a height of at least two hundred and no more than three hundred micrometers.

[0034] The bottom chamber 150 has a height h2. In some embodiments, the height of the bottom chamber 150 is sufficient to accommodate the movement of the cooling element 120. Therefore, during normal operation, no part of the cooling element 120 contacts the orifice plate 130. The bottom chamber 150 is generally smaller than the top chamber 140 and can help reduce fluid backflow into the orifice 132. In some embodiments, the height of the bottom chamber 150 is the maximum deflection of the cooling element 120 plus at least five micrometers and no more than ten micrometers. In some embodiments, the deflection of the cooling element 120 (e.g., the deflection of the end 121) z has an amplitude of at least ten micrometers and no more than one hundred micrometers. In some such embodiments, the deflection amplitude of the cooling element 120 is at least ten micrometers and no more than sixty micrometers. However, the deflection amplitude of the cooling element 120 depends on factors such as the desired flow rate through the cooling system 100 and the construction of the cooling system 100. Therefore, the height of the bottom chamber 150 depends generally on the flow rate through other components of the cooling system 100.

[0035] The top panel 110 includes a vent 112 through which fluid is drawn into the cooling system 100. The top vent 112 may have a size selected based on the desired sound pressure level in the top chamber 140. For example, in some embodiments, the width w of the vent 112 is at least 500 micrometers and no more than 1,000 micrometers. In some embodiments, the width of the vent 112 is at least 250 micrometers and no more than 2,000 micrometers. In the illustrated embodiment, the vent 112 is a centrally located aperture in the top panel 110. In other embodiments, the vent 112 may be located elsewhere. For example, the vent 112 may be closer to one of the edges of the top panel 110. The vent 112 may have a circular, rectangular, or other shaped footprint. Although a single vent 112 is shown, multiple vents may be used. For example, the vents may be offset toward the edge of the top chamber 140 or located on one or more sides of the top chamber 140. Although the top plate 110 is shown as substantially flat, in some embodiments, grooves and / or other structures may be provided in the top plate 110 to modify the construction of the top chamber 140 and / or the area above the top plate 110.

[0036] Anchor 160 (support structure) supports the cooling element 120 at its central portion. Therefore, at least a portion of the periphery of the cooling element 120 is unpinned and can vibrate freely. In some embodiments, the anchor 160 is positioned along the central axis of the cooling element 120 (e.g., perpendicular to...). Figure 1A-1E (The page in the document extends). In such embodiments, a portion of the vibrating cooling element 120 (e.g., including end 121) moves in a cantilever manner. Therefore, portions of the cooling element 120 can move in a manner similar to butterfly wings (i.e., in phase) and / or similar to a seesaw (i.e., out of phase). Thus, portions of the cantilever-vibrating cooling element 120 are in phase in some embodiments and out of phase in others. In some embodiments, the anchor 160 does not extend along the axis of the cooling element 120. In such embodiments, all portions of the periphery of the cooling element 120 are free to vibrate (e.g., similar to a jellyfish). In the illustrated embodiment, the anchor 160 supports the cooling element 120 from the bottom. In other embodiments, the anchor 160 may support the cooling element 120 in other ways. For example, the anchor 160 may support the cooling element 120 from the top (e.g., the cooling element 120 is suspended from the anchor 160). In some embodiments, the width 'a' of the anchor 160 is at least 0.5 mm and no more than 4 mm. In some embodiments, the width of the anchor 160 is at least two millimeters and no more than 2.5 millimeters. The anchor 160 may occupy at least 10 percent and no more than 50 percent of the cooling element 120.

[0037] The cooling element 120 has a first side away from the heat-generating structure 102 and a second side adjacent to the heat-generating structure 102. Figure 1A-1E In the illustrated embodiment, the first side of the cooling element 120 is the top of the cooling element 120 (closer to the top plate 110) and the second side is the bottom of the cooling element 120 (closer to the perforated plate 130). Figure 1A-1EAs shown, cooling element 120 is actuated to undergo vibratory motion. This vibratory motion drives fluid from a first side of cooling element 120 away from heat-generating structure 102 (e.g., from top chamber 140) to a second side of cooling element 120 adjacent to heat-generating structure 102 (e.g., to bottom chamber 150). The vibratory motion also draws fluid through vent 112 and into top chamber 140; forces fluid from top chamber 140 to bottom chamber 150; and drives fluid from bottom chamber 150 through orifice 132 of orifice plate 130. Thus, cooling element 120 can be considered an actuator. Although described in the context of a single, continuous cooling element, in some embodiments, cooling element 120 may be formed of two (or more) cooling elements. One portion of each cooling element is fixed (e.g., supported by anchor 160) and the opposing portions are not fixed. Therefore, a single centrally supported cooling element 120 may be formed by a combination of multiple cooling elements supported at the edges.

[0038] The cooling element 120 has a length L, which depends on the desired frequency of vibration of the cooling element 120. In some embodiments, the length of the cooling element 120 is at least four millimeters and no more than ten millimeters. In some such embodiments, the cooling element 120 has a length of at least six millimeters and no more than eight millimeters. The depth of the cooling element 120 (e.g., perpendicular to...) Figure 1A-1E The plane shown can vary from one-quarter to twice the length of L. For example, the cooling element 120 may have a depth equal to its length. The thickness t of the cooling element 120 may vary based on the construction of the cooling element 120 and / or the frequency at which the cooling element 120 is expected to be actuated. In some embodiments, for a cooling element 120 having a length of eight millimeters and driven at a frequency of at least twenty kilohertz and no more than twenty-five kilohertz, the cooling element thickness is at least two hundred micrometers and no more than three hundred and fifty micrometers. The length C of the top chamber 140 / bottom chamber 150 is close to the length L of the cooling element 120. For example, in some embodiments, the distance d between the edge of the cooling element 120 and the wall of the top chamber 140 / bottom chamber 150 is at least one hundred micrometers and no more than five hundred micrometers. In some embodiments, d is at least two hundred micrometers and no more than three hundred micrometers.

[0039] Cooling element 120 can be driven at or near the resonant frequency of the acoustic resonance of the pressure wave in the fluid in top chamber 140 and the resonant frequency of the structural resonance of cooling element 120. The portion of cooling element 120 experiencing vibrational motion is driven at or near the resonance (“structural resonance”) of cooling element 120. In some embodiments, this vibrating portion of cooling element 120 may be a cantilever segment. The vibrational frequency of structural resonance is called the structural resonance frequency. Using the structural resonance frequency in driving cooling element 120 reduces the power consumption of cooling system 100. Cooling element 120 and top chamber 140 may also be configured such that the structural resonance frequency corresponds to the resonance (acoustic resonance of top chamber 140) of the pressure wave in the fluid driving through top chamber 140. The frequency of such pressure wave is called the acoustic resonance frequency. Under acoustic resonance, pressure nodes appear near vent 112 and pressure antinodes appear near the periphery of cooling system 100 (e.g., near the end 121 of cooling element 120 and near the junction between top chamber 140 and bottom chamber 150). The distance between these two regions is C / 2. Therefore, C / 2 = nλ / 4, where λ is the acoustic wave length of the fluid, and n is an odd number (e.g., n = 1, 3, 5, etc.). For the lowest order mode, C = λ / 2. Since the length of the top chamber 140 (e.g., C) is close to the length of the cooling element 120, in some embodiments, L / 2 = nλ / 4 is also approximately correct, where λ is the acoustic wave length of the fluid, and n is an odd number. Therefore, the frequency ν driving the cooling element 120 is at or near the structural resonant frequency of the cooling element 120. The frequency ν is also at or near the acoustic resonant frequency of at least the top chamber 140. Compared to the structural resonant frequency of the cooling element 120, the acoustic resonant frequency of the top chamber 140 changes less drastically with parameters such as temperature and size. Therefore, in some embodiments, the cooling element 120 may be driven at (or closer to) the structural resonant frequency rather than the acoustic resonant frequency.

[0040] An orifice plate 130 has orifices 132 therein. Although a specific number and distribution of orifices 132 are shown, other numbers and / or other distributions may be used. A single orifice plate 130 is used for a single cooling system 100. In other embodiments, multiple cooling systems 100 may share an orifice plate. For example, multiple cooling systems 100 may be provided together in a desired configuration. In such embodiments, cooling systems 100 may be of the same size and configuration or (multiple) different sizes and / or configurations. The orifice 132 is shown as having an axis oriented normally to the surface of the heat-generating structure 102. In other embodiments, the axes of one or more orifices 132 may be at other angles. For example, the angle of the axis may be selected from a substantially zero degree and a non-zero acute angle. The orifice 132 also has sidewalls that are substantially parallel to the normal to the surface of the orifice plate 130. In some embodiments, the orifice may have sidewalls at a non-zero angle to the normal to the surface of the orifice plate 130. For example, the orifice 132 may be tapered. Furthermore, although the orifice plate 130 is shown as substantially flat, in some embodiments, grooves and / or other structures may be provided in the orifice plate 130 to modify the configuration of the bottom chamber 150 and / or the region between the orifice plate 130 and the heat generation structure 102.

[0041] The size, distribution, and location of orifice 132 are selected to control the flow rate of fluid driven to the surface of heat-generating structure 102. The location and configuration of orifice 132 can be configured to increase / maximize fluid flow from bottom chamber 150 through orifice 132 to the injection channel (the region between the bottom of orifice plate 130 and the top of heat-generating structure 102). The location and configuration of orifice 132 can also be selected to reduce / minimize suction flow (e.g., backflow) from injection channel through orifice 132. For example, it is desirable that the orifice be located sufficiently far from end 121 to reduce suction during the upward stroke of cooling element 120 (when end 121 moves away from orifice plate 13), which draws fluid through orifice 132 into bottom chamber 150. It is also desirable that the orifice be located sufficiently close to end 121 so that suction during the upward stroke of cooling element 120 also allows higher pressure from top chamber 140 to push fluid from top chamber 140 into bottom chamber 150. In some embodiments, the ratio (“net flow ratio”) of the flow velocity entering the bottom chamber 150 from the top chamber 140 during the upward stroke to the flow velocity passing through the orifice 132 from the injection channel is greater than 2:1. In some embodiments, the net flow ratio is at least 85:15. In some embodiments, the net flow ratio is at least 90:10. To provide the desired pressure, flow rate, suction, and net flow ratio, it is desirable that the orifice 132 is at least r1 from the end 121 and no more than r2 from the end 121 of the cooling element 120. In some embodiments, r1 is at least one hundred micrometers (e.g., r1 ≥ 100 μm), while r2 is no more than one millimeter (e.g., r2 ≤ 1000 μm). In some embodiments, the orifice 132 is at least two hundred micrometers from the end 121 of the cooling element 120 (e.g., r1 ≥ 200 μm). In some such embodiments, the orifice 132 is at least three hundred micrometers from the end 121 of the cooling element 120 (e.g., r1 ≥ 300 μm). In some embodiments, orifice 132 has a width σ of at least 100 micrometers and no more than 500 micrometers. In some embodiments, orifice 132 has a width of at least 200 micrometers and no more than 300 micrometers. In some embodiments, the orifice spacing s is at least 100 micrometers and no more than 1 millimeter. In some such embodiments, the orifice spacing is at least 400 micrometers and no more than 600 micrometers. In some embodiments, it is also desirable for orifice 132 to occupy a specific share of the area of ​​orifice plate 130. For example, orifice 132 may cover at least 5% and no more than 15% of the occupied area of ​​orifice plate 130 in order to achieve a desired flow rate of fluid through orifice 132. In some embodiments, orifice 132 covers at least 8% and no more than 12% of the occupied area of ​​orifice plate 130.

[0042] In some embodiments, the cooling element 120 is actuated using a piezoelectric element. Therefore, the cooling element 120 may be a piezoelectric cooling element. The cooling element 120 may be driven by a piezoelectric element mounted on or integrated into the cooling element 120. In some embodiments, the cooling element 120 is driven in other ways, including but not limited to disposing the piezoelectric element on other structures within the cooling system 100. The cooling element 120 and similar cooling elements are hereinafter referred to as piezoelectric cooling elements, but mechanisms other than piezoelectric elements may be used to drive the cooling element. In some embodiments, the cooling element 120 includes a piezoelectric layer on a substrate. The substrate may be a stainless steel, Ni alloy, and / or Hastelloy substrate. In some embodiments, the piezoelectric layer includes a plurality of sublayers formed as thin films on the substrate. In other embodiments, the piezoelectric layer may be a body layer attached to the substrate. Such a piezoelectric cooling element 120 also includes electrodes for activating the piezoelectric element. In some embodiments, the substrate serves as the electrode. In other embodiments, a bottom electrode may be disposed between the substrate and the piezoelectric layer. The piezoelectric cooling element may include other layers, including but not limited to a seed layer, a capping layer, a passivation layer, or other layers. Therefore, the cooling element 120 can be actuated using a piezoelectric material.

[0043] In some embodiments, the cooling system 100 includes vents (not shown) or other conduits. Such conduits provide a path for heated fluid to flow away from the heat-generating structure 102. In some embodiments, the conduits return fluid to the side of the top plate 110 away from the heat-generating structure 102. In some embodiments, the conduits may instead direct fluid away from the heat-generating structure 102 in a direction parallel to or perpendicular to the heat-generating structure 102 but in the opposite direction (e.g., towards the bottom of the page). For devices using external fluids in the cooling system 100, the conduits may direct heated fluid to vents. In such embodiments, additional fluid may be provided from the inlet vent. In embodiments where the device is closed, the conduits may provide a circuitous path back to an area near the vent 112 and away from the heat-generating structure 102. Such a path allows the fluid to dissipate heat before being reused to cool the heat-generating structure 102. In other embodiments, the conduits may be omitted or otherwise constructed. Thus, the fluid is allowed to carry heat away from the heat-generating structure 102.

[0044] exist Figure 1A-1E The operation of the cooling system 100 is described in the context of specific pressures, clearance sizes, and flow times. Although described in the context of specific pressures, clearance sizes, and flow times, the operation of the cooling system 100 does not depend on the interpretation herein. Figure 1B-1C The in-phase operation of the cooling system 100 is depicted. See also... Figure 1B The cooling element 120 is actuated, causing its end 121 to move away from the top plate 110. Therefore, it can be considered that... Figure 1BThe end of the downward stroke of the cooling element 120 is depicted. Due to the vibratory motion of the cooling element 120, the size of the gap 152 in the bottom chamber 150 decreases and is shown as gap 152B. Conversely, the size of the gap 142 in the top chamber 140 increases and is shown as gap 142B. During the downward stroke, when the cooling element 120 is in the neutral position, a lower (e.g., minimum) pressure is formed at the periphery. As the downward stroke continues, as... Figure 1B As shown, the size of the bottom chamber 150 decreases while the size of the top chamber 140 increases. Therefore, fluid is driven out of the orifice 132 in a direction perpendicular to or nearly perpendicular to the surface of the orifice plate 130 and / or the top surface of the heat-generating structure 102. The fluid is driven from the orifice 132 toward the heat-generating structure 102 at a high speed (e.g., exceeding thirty-five meters per second). In some embodiments, the fluid then travels along the surface of the heat-generating structure 102 and toward the periphery of the heat-generating structure 102, where the pressure is lower than near the orifice 132. Also during the downstroke, the size of the top chamber 140 increases and a lower pressure exists in the top chamber 140. As a result, fluid is drawn into the top chamber 140 through the vent 112. The fluid entering the vent 112, passing through the orifice 132, and moving along the surface of the heat-generating structure 102... Figure 1B The arrow in the middle is not marked.

[0045] The cooling element 120 is also actuated, causing the end 121 to move away from the heat-generating structure 102 and toward the top plate 110. Therefore, it can be considered that... Figure 1C The end of the upward stroke of cooling element 120 is depicted. Due to the movement of cooling element 120, the size of gap 142 decreases and is shown as gap 142C. The size of gap 152 increases and is shown as gap 152C. During the upward stroke, when cooling element 120 is in the neutral position, a higher (e.g., maximum) pressure is formed at the periphery. As the upward stroke continues, as... Figure 1C As shown, the size of the bottom chamber 150 increases while the size of the top chamber 140 decreases. Therefore, fluid is driven from the top chamber 140 (e.g., the periphery of the top chamber 140 / bottom chamber 150) to the bottom chamber 150. Thus, as the end 121 of the cooling element 120 moves upward, the top chamber 140 acts as a nozzle to accelerate the incoming fluid and drive it toward the bottom chamber 150. The movement of fluid into the bottom chamber 150... Figure 1CThe image is shown by an unmarked arrow. The location and configuration of the cooling element 120 and orifice 132 are chosen to reduce suction and thus reduce fluid backflow from the injection channel (between the heat-generating structure 102 and the orifice plate 130) into the orifice 132 during the upward stroke. Therefore, the cooling system 100 is able to drive fluid from the top chamber 140 to the bottom chamber 150 without excessive backflow of heated fluid from the injection channel into the bottom chamber. Furthermore, the cooling system 100 is operable such that fluid is drawn in through the vent 112 and driven out through the orifice 132, while the cooling element 120 does not contact the top plate 110 or the orifice plate 130. Thus, as described herein, pressure is created within the top chamber 140 and the bottom chamber 150, which effectively opens and closes the vent 112 and the orifice 132, allowing fluid to be driven through the cooling system 100.

[0046] repeat Figure 1B and Figure 1C The movement between the positions shown. Therefore, the cooling element 120 experiences... Figure 1A-1C The vibrational movements indicated herein are used to draw fluid from the distal side of the top plate 110 through the vent 112 into the top chamber 140; to transfer fluid from the top chamber 140 to the bottom chamber 150; and to push fluid through the orifice 132 and toward the heat-generating structure 102. As described above, the cooling element 120 is driven to vibrate at or near its structural resonant frequency. Furthermore, the structural resonant frequency of the cooling element 120 is configured to align with the acoustic resonance of the top chamber 140 / bottom chamber 150. The structural resonant frequency and the acoustic resonant frequency are generally selected to be within the ultrasonic range. For example, the vibrational movements of the cooling element 120 may be at frequencies from 15 kHz to 30 kHz. In some embodiments, the cooling element 120 vibrates at one or more frequencies of at least 20 kHz and no more than 30 kHz. The structural resonant frequency of the cooling element 120 is within ten percent of the acoustic resonant frequency of the cooling system 100. In some embodiments, the structural resonant frequency of the cooling element 120 is within five percent of the acoustic resonant frequency of the cooling system 100. In some embodiments, the structural resonant frequency of the cooling element 120 is within three percent of the acoustic resonant frequency of the cooling system 100. Therefore, efficiency and flow rate can be improved. However, other frequencies can be used.

[0047] Fluid driven toward the heat-generating structure 102 can move substantially normal (perpendicular) to the top surface of the heat-generating structure 102. In some embodiments, the fluid movement can have a non-zero acute angle relative to the normal of the top surface of the heat-generating structure 102. In either case, the fluid can thin and / or form pores in the boundary layer of the fluid at the heat-generating structure 102. As a result, heat transfer from the heat-generating structure 102 can be improved. The fluid deflects away from the heat-generating structure 102 to travel along the surface of the heat-generating structure 102. In some embodiments, the fluid moves in a direction substantially parallel to the top of the heat-generating structure 102. Therefore, heat from the heat-generating structure 102 can be extracted by the fluid. The fluid can exit the region between the orifice plate 130 and the heat-generating structure 102 at the edge of the cooling system 100. Vents or other conduits (not shown) at the edge of the cooling system 100 allow fluid to be carried away from the heat-generating structure 102. In other embodiments, the heated fluid can be further transferred from the heat-generating structure 102 in other ways. The fluid can exchange heat transferred from the heat-generating structure 102 to other structures or to the surrounding environment. Therefore, the fluid at the distal end of the top plate 110 can remain relatively cool to allow for additional heat extraction. In some embodiments, the fluid is circulated to return to the distal end of the top plate 110 after cooling. In other embodiments, the heated fluid is carried away and replaced by fresh fluid at the distal end of the cooling element 120. As a result, the heat-generating structure 102 can be cooled.

[0048] Figure 1D-1E An embodiment of an active cooling system 100 including a centrally anchored cooling element 120 is depicted, wherein the cooling element is driven out of phase. More specifically, sections of the cooling element 120 on opposite sides of the anchor 160 (and thus on opposite sides of the central region of the cooling element 120 supported by the anchor 160) are driven to vibrate out of phase. In some embodiments, the sections of the cooling element 120 on opposite sides of the anchor 160 are driven at or near 180 degrees out of phase. Thus, one section of the cooling element 120 vibrates toward the top plate 110, while another section of the cooling element 120 vibrates toward the orifice plate 130 / heat generation structure 102. The movement of the section of the cooling element 120 toward the top plate 110 (upward stroke) drives fluid in the top chamber 140 to the bottom chamber 150 on the side of the anchor 160. The movement of the section of the cooling element 120 toward the orifice plate 130 drives fluid through the orifice 132 and toward the heat generation structure 102. Therefore, fluid traveling at high speed (e.g., relative to the speed described in the in-phase operation) is alternately driven out of the orifices 132 on opposite sides of the anchor 160. The movement of the fluid is caused by... Figure 1D and Figure 1E The unmarked arrows are shown.

[0049] repeat Figure 1D and Figure 1E The movement between the positions shown. Therefore, the cooling element 120 experiences... Figure 1A , Figure 1D and Figure 1E The vibrational movements indicated herein alternately draw fluid from the distal side of the top plate 110 through vents 112 into each side of the top chamber 140 for cooling element 120; transfer fluid from each side of the top chamber 140 to the corresponding side of the bottom chamber 150; and propel fluid through orifices 132 on each side of the anchor 160 and toward the heat-generating structure 102. As described above, cooling element 120 is driven to vibrate at or near its structural resonant frequency. Furthermore, the structural resonant frequency of cooling element 120 is configured to align with the acoustic resonance of the top chamber 140 / bottom chamber 150. The structural resonant frequency and the acoustic resonant frequency are generally selected to be within the ultrasonic range. For example, the vibrational movements of cooling element 120 may be at frequencies described for in-phase vibration. The structural resonant frequency of cooling element 120 is within ten percent of the acoustic resonant frequency of cooling system 100. In some embodiments, the structural resonant frequency of cooling element 120 is within five percent of the acoustic resonant frequency of cooling system 100. In some embodiments, the structural resonant frequency of the cooling element 120 is within three percent of the acoustic resonant frequency of the cooling system 100. Therefore, efficiency and flow rate can be improved. However, other frequencies can be used.

[0050] Fluid driven toward the heat-generating structure 102 to perform out-of-phase vibrations can move substantially normal (perpendicular) to the top surface of the heat-generating structure 102 in a manner similar to that described above for in-phase operation. Similarly, vents or other conduits (not shown) at the edges of the cooling system 100 allow fluid to be removed from the heat-generating structure 102. In other embodiments, heated fluid can be further transferred from the heat-generating structure 102 in other ways. The fluid can exchange heat transferred from the heat-generating structure 102 to other structures or to the surrounding environment. Thus, the fluid at the distal side of the top plate 110 can remain relatively cool to allow for additional heat extraction. In some embodiments, the fluid is circulated to return to the distal side of the top plate 110 after cooling. In other embodiments, heated fluid is carried away and replaced by fresh fluid at the distal side of the cooling element 120. As a result, the heat-generating structure 102 can be cooled.

[0051] Despite Figure 1A-1E The cooling system 100 is shown in the context of a uniform cooling element, but the cooling system 100 may utilize cooling elements of different shapes. Figure 1FAn embodiment of an engineered cooling element 120' is depicted, having a customized geometry and usable in a cooling system such as cooling system 100. Cooling element 120' includes an anchoring region 122 and a cantilever 123. The anchoring region 122 is supported (e.g., held in place) in cooling system 100 by anchors 160. The cantilever 123 undergoes vibratory movement in response to an actuated cooling element 120'. Each cantilever 123 includes a stepped region 124, an extension region 126, and an outer region 128. Figure 1F In the illustrated embodiment, the anchoring region 122 is centrally located. A stepped region 124 extends outward from the anchoring region 122. An extension region 126 extends outward from the stepped region 124. An outer region 128 extends outward from the extension region 126. In other embodiments, the anchoring region 122 may be located at one edge of the actuator, while the outer region 128 may be located at the opposite edge. In such embodiments, the actuator is edge-anchored.

[0052] The extension region 126 has a thickness (extension thickness) that is less than the thickness of the step region 124 (step thickness) and less than the thickness of the outer region 128 (outer thickness). Therefore, the extension region 126 can be considered recessed. The extension region 126 can also be considered to provide a larger bottom chamber 150. In some embodiments, the outer thickness of the outer region 128 is the same as the step thickness of the step region 124. In some embodiments, the outer thickness of the outer region 128 is different from the step thickness of the step region 124. In some embodiments, the outer region 128 and the step region 124 each have a thickness of at least 320 micrometers and no more than 360 micrometers. In some embodiments, the outer thickness is at least 50 micrometers thicker than the extension thickness and no more than 200 micrometers. In other words, the step (the difference between the step thickness and the extension thickness) is at least 50 micrometers and no more than 200 micrometers. In some embodiments, the outer step (the difference between the outer thickness and the extension thickness) is at least 50 micrometers and no more than 200 micrometers. The outer region 128 may have a width of at least 100 micrometers and no more than 300 micrometers. In some embodiments, the extension region has a length e extending outward from the stepped region by at least 0.5 mm and no more than 1.5 mm. In some embodiments, the outer region 128 has a higher mass per unit length than the extension region 126 in the direction from the anchoring region 122. This mass difference may be due to the larger size of the outer region 128, density differences between portions of the cooling element 120, and / or other mechanisms.

[0053] The use of engineered cooling element 120' further improves the efficiency of cooling system 100. The extended region 126 is thinner than the stepped region 124 and the outer region 128. This results in a cavity in the bottom of cooling element 120' corresponding to the extended region 126. The presence of this cavity contributes to improved efficiency of cooling system 100. Each cantilever 123 vibrates towards the top plate 110 during the upward stroke and vibrates away from the top plate 110 during the downward stroke. When the cantilever 123 moves towards the top plate 110, the higher pressure fluid in the top chamber 140 resists the movement of the cantilever 123. Furthermore, the suction in the bottom chamber 150 also resists the upward movement of the cantilever 123 during the upward stroke. During the downward stroke of the cantilever 123, the increased pressure in the bottom chamber 150 and the suction in the top chamber 140 resist the downward movement of the cantilever 123. However, the presence of the cavity in the cantilever 123 corresponding to the extended region 126 mitigates the suction in the bottom chamber 150 during the upward stroke. This cavity also reduces the pressure increase in the bottom chamber 150 during the downward stroke. Because the suction and pressure increase are reduced in magnitude, the cantilever 123 can move more easily through the fluid. This is achieved while substantially maintaining the higher pressure of the driving fluid in the top chamber 140 flowing through the cooling system 100. Furthermore, the presence of the outer region 128 improves the cantilever 123's ability to move through the fluid driven through the cooling system 100. The outer region 128 has a higher mass per unit length and therefore a higher momentum. Thus, the outer region 128 improves the cantilever 123's ability to move through the fluid driven through the cooling system 100. The magnitude of the cantilever 123's deflection can also be increased. These benefits can be achieved while maintaining the stiffness of the cantilever 123 by using a thicker stepped region 124. Furthermore, the greater thickness of the outer region 128 helps to pinch off the flow at the bottom of the downward stroke. Therefore, the cooling element 120''s ability to provide a valve to prevent backflow through the orifice 132 is improved. Therefore, the performance of the cooling system 100 employing cooling element 120' can be improved.

[0054] Using a cooling system 100 actuated to in-phase or out-of-phase vibrations for cooling elements 120 and / or 120', fluid drawn in through vent 112 and driven through orifice 132 can effectively dissipate heat from the heat-generating structure 102. Because the fluid impacts the heat-generating structure at a sufficient velocity (e.g., at least thirty meters per second) and, in some embodiments, substantially normal to the heat-generating structure, the boundary layer of the fluid at the heat-generating structure can be thinned and / or partially removed. Therefore, heat transfer between the heat-generating structure 102 and the moving fluid is improved. Due to the more efficient cooling of the heat-generating structure, the corresponding integrated circuit can operate at higher speeds and / or power for longer periods. For example, if the heat-generating structure corresponds to a high-speed processor, such a processor may operate for longer periods before throttling. Therefore, the performance of devices utilizing the cooling system 100 can be improved. Furthermore, the cooling system 100 can be a MEMS device. Therefore, the cooling system 100 is suitable for use in smaller devices and / or mobile devices with limited available space, such as smartphones, other mobile phones, virtual reality headsets, tablets, 2-in-1 computers, wearable devices, and handheld game consoles. Therefore, the performance of such a device can be improved. Since the cooling elements 120 / 120' may vibrate at frequencies of 15 kHz or higher, the user may not hear any noise associated with the actuation of the cooling elements. If the actuation is performed at or near the structural resonant frequency and / or acoustic resonant frequency, the power used to operate the cooling system can be significantly reduced. The cooling elements 120 / 120' do not physically contact the top plate 110 or the orifice plate 130 during vibration. Therefore, it is easier to maintain the resonance of the cooling elements 120 / 120'. More specifically, physical contact between the cooling elements 120 / 120' and other structures disrupts the resonant conditions of the cooling elements 120 / 120'. Disruption of these conditions may drive the cooling elements 120 / 120' out of resonance. Therefore, additional power will be required to maintain the actuation of the cooling elements 120 / 120'. Furthermore, the fluid flow driven by the cooling elements 120 / 120' can be reduced. As mentioned above, these problems can be avoided by using pressure differentials and fluid flow. The benefits of improved, quieter cooling can be achieved using limited additional power. Furthermore, the out-of-phase vibration of the cooling elements 120 / 120' allows the center of mass of the cooling system 100 to remain more stable. Although torque is applied to the cooling elements 120 / 120', the forces caused by the movement of the center of mass are reduced or eliminated. As a result, vibrations caused by the movement of the cooling elements 120 / 120' are reduced. Moreover, the efficiency of the cooling system 100 can be improved by using out-of-phase vibration motion on both sides of the cooling elements 120 / 120'. Therefore, the performance of the device incorporating the cooling system 100 can be improved. Furthermore, the cooling system 100 can be used in other applications where higher fluid flow and / or velocity are desired (e.g., with or without the heat-generating structure 102).

[0055] Figure 2A-2B A plan view depicting embodiments of cooling systems 200A and 200B, which are similar to active cooling systems such as cooling system 100. Figure 2A and Figure 2B Not drawn to scale. For simplicity, only portions of cooling elements 220A and 220B, and anchors 260A and 260B are shown. Cooling elements 220A and 220B are similar to cooling elements 120 / 120'. Therefore, the size and / or material for cooling elements 220A and / or 220B may be similar to the size and / or material for cooling elements 120 / 120'. Anchors (support structures) 260A and 260B are similar to anchor 160 and are indicated by dashed lines.

[0056] For cooling elements 220A and 220B, anchors 260A and 260B are centrally located and extend along the central axes of cooling elements 220A and 220B, respectively. Therefore, cantilever portions actuated to vibrate are located on the right and left sides of anchors 260A and 260B. In some embodiments, cooling elements(s) 220A and / or 220B are a continuous structure, with both portions actuated (e.g., cantilever portions outside anchors 260A and 260B). In some embodiments, cooling elements(s) 220A and / or 220B include separate cantilever portions, each of which is attached to and actuated by anchors 260A and 260B, respectively. The cantilever portions of cooling elements 220A and 220B can therefore be configured to vibrate in a manner similar to butterfly wings (in-phase) or similar to a seesaw (out-of-phase). Figure 2A and Figure 2B In this context, L represents the length of the cooling element, similar to... Figure 1A-1E The length described in the text. Also in... Figure 2A and Figure 2B The depth P of cooling elements 220A and 220B is indicated in the text.

[0057] exist Figure 2A-2B The piezoelectric element 223 is also shown by dashed lines. The piezoelectric element 223 is used to actuate cooling elements 220A and 220B. In some embodiments, the piezoelectric element 223 may be located in other regions and / or have a different configuration. Although described in the context of a piezoelectric element, other mechanisms for actuating cooling elements 220A and 220B may be used. Such other mechanisms may be located at the location of the piezoelectric element 223 or may be located elsewhere. In cooling element 220A, the piezoelectric element 223 may be attached to a cantilever portion or may be integrated into cooling element 220A. Furthermore, although the piezoelectric element 223 is... Figure 2A and Figure 2B It is shown as having a specific shape and size, but other constructions can be used.

[0058] exist Figure 2A In the illustrated embodiment, anchor 260A extends the entire depth of cooling element 220A. Therefore, a portion of the periphery of cooling element 220A is fixed. The unfixed portion of the periphery of cooling element 220A is the part of the cantilever section that experiences vibrational movement. In other embodiments, the anchor does not need to extend the entire length of the central axis. In such embodiments, the entire periphery of the cooling element is unfixed. However, such a cooling element still has a cantilever section configured to vibrate in the manner described herein. For example, in Figure 2B In this configuration, anchor 260B does not extend to the periphery of cooling element 220B. Therefore, the periphery of cooling element 220B is not fixed. However, anchor 260B still extends along the central axis of cooling element 220B. Cooling element 220B is still actuated, causing the cantilever portion to vibrate (e.g., similar to a butterfly's wing).

[0059] Although the cooling element 220A is depicted as rectangular, the cooling element may have other shapes. In some embodiments, the corners of the cooling element 220A may be rounded. Figure 2B The cooling element 220B has a rounded cantilever section. Other shapes are also possible. Figure 2B In the illustrated embodiment, anchor 260B is hollow and includes a hole 263. In some embodiments, cooling element 220B has a plurality of holes in the region of anchor 260B. In some embodiments, cooling element 220B includes multiple portions such that a plurality of holes exist in the region of anchor 260B. As a result, fluid can be drawn through cooling element 220B and through anchor 260B. Therefore, cooling element 220B can be used in place of a top plate such as top plate 110. In such embodiments, the holes and holes 263 in cooling element 220B can function in a manner similar to vent 112. Furthermore, although cooling systems 200A and 200B are depicted as supported in a central region, in some embodiments, a cantilever section of cooling element 220A and / or 220B may be omitted. In such embodiments, cooling element 220A and / or 220B can be considered as supported or anchored at or near an edge, while at least a portion of the edge is free to undergo vibrational movement. In some such embodiments, cooling elements 220A and / or 220B may include a single cantilever segment that undergoes vibrational motion.

[0060] Figures 3A-3B Plan views depicting embodiments of cooling systems 300A and 300B, which are similar to active cooling systems such as cooling system 100. Figure 3A and Figure 3BNot drawn to scale. For simplicity, only cooling elements 320A and 320B, and anchors 360A and 360B are shown. Cooling elements 320A and 320B are similar to cooling elements 120 / 120'. Therefore, the size and / or material for cooling elements 320A and / or 320B may be similar to the size and / or material for cooling elements 120 / 120'. Anchors 360A and 360B are similar to anchor 160 and are indicated by dashed lines.

[0061] For cooling elements 320A and 320B, anchors 360A and 360B are respectively confined to the central regions of cooling elements 320A and 320B. Therefore, the regions surrounding anchors 360A and 360B experience vibratory movement. Cooling elements 320A and 320B can thus be configured to vibrate in a manner similar to the opening / closing of a jellyfish or an umbrella. In some embodiments, the entire periphery of cooling elements 320A and 320B vibrates in phase (e.g., all move upwards or downwards together). In other embodiments, the peripheral portions of cooling elements 320A and 320B vibrate out of phase. Figure 3A and Figure 3B In this context, L is the length (e.g., diameter) of the cooling element, similar to... Figure 1A-1E The length is depicted in the figure. Although cooling elements 320A and 320B are depicted as circular, cooling elements may have other shapes. Furthermore, piezoelectric elements ( Figures 3A-3B (not shown) and / or other mechanisms to drive the vibrational movement of cooling elements 320A and 320B.

[0062] exist Figure 3B In the illustrated embodiment, anchor 360B is hollow and has pores 363. In some embodiments, cooling element 320B has pores(s) in the region of anchor 360B. In some embodiments, cooling element 320B comprises multiple portions such that pores(s) exist in the region of anchor 360B. As a result, fluid can be drawn through cooling element 320B and through anchor 360B. Fluid can exit through pores 363. Therefore, cooling element 320B can be used in place of a top plate such as top plate 110. In such embodiments, the pores and pores 363 in cooling element 320B can function similarly to vent 112.

[0063] Cooling systems such as cooling system 100 can utilize multiple cooling elements 220A, 220B, 320A, 320B and / or similar cooling elements. Such cooling systems can also share the benefits of cooling system 100. Cooling systems using multiple cooling elements 220A, 220B, 320A, 320B and / or similar cooling elements can more effectively drive fluid at high speed toward the heat-generating structure. Therefore, heat transfer between the heat-generating structure and the moving fluid is improved. Because the heat-generating structure is cooled more effectively, the corresponding device can exhibit improved operation, such as operating at higher speeds and / or power for longer periods. Cooling systems employing multiple cooling elements 220A, 220B, 320A, 320B and / or similar cooling elements are suitable for use in smaller devices and / or mobile devices with limited available space. Therefore, the performance of such devices can be improved. Because the cooling elements(s) 220A, 220B, 320A, 320B and / or similar cooling elements may vibrate at frequencies of 15 kHz or higher, the user may not hear any noise associated with the actuation of the cooling elements. If the cooling elements(s) 220A, 220B, 320A, 320B and / or similar cooling elements are driven at or near their acoustic and / or structural resonant frequencies, the power used in the operating cooling system can be significantly reduced. The cooling elements(s) 220A, 220B, 320A, 320B and / or similar cooling elements may not physically contact the plate during use, allowing for easier maintenance of resonance. The benefits of improved, quieter cooling can be achieved with limited additional power. Therefore, the performance of devices incorporating the cooling elements(s) 220A, 220B, 320A, 320B and / or similar cooling elements can be improved.

[0064] Figures 4A-4B An embodiment of an active cooling system 400 including a cooling element anchored at the top center is depicted. Figure 4A A side view of the cooling system 400 in a neutral position is depicted. Figure 4B A top view of the cooling system 400 is depicted. Figures 4A-4B Not drawn to scale. For simplicity, only a portion of the cooling system 400 is shown. See also Figure 4A-10 B. Cooling system 400 is similar to cooling system 100. Therefore, similar components have similar markings. For example, cooling system 400 is used in conjunction with heat generation structure 402, which is similar to heat generation structure 102.

[0065] The cooling system 400 includes a top plate 410 with a vent 412, a cooling element 420, an orifice plate 430 with an opening 432, a top chamber 440 with a gap, a bottom chamber 450 with a gap, flow chambers 440 / 450, and anchors (i.e., support structures) 460, which are respectively similar to the top plate 110 with a vent 112, the cooling element 220, the orifice plate 130 with an opening 132, the top chamber 140 with a gap 142, the bottom chamber 150 with a gap 152, the flow top chamber 140 / bottom chamber 150, and the anchors 160 (i.e., support structures). Therefore, the cooling element 420 is centrally supported by the anchors 460, such that at least a portion of the periphery of the cooling element 420 is free to vibrate. In some embodiments, the anchors 460 extend along the axis of the cooling element 420 (e.g., in a manner similar to anchors 260A and / or 260B). In other embodiments, anchor 460 is only located near the central portion of cooling element 420 (e.g., similar to anchors 460C and / or 460D). Although in Figure 4A and Figure 4B While not explicitly labeled, cooling element 420 includes an anchoring region and cantilevered regions including a stepped region, an extension region, and an outer region, which are similar to the anchoring region 122, cantilever 123, stepped region 124, extension region 126, and outer region 128 of cooling element 120'. In some embodiments, the cantilevered regions of cooling element 420 are driven in phase. In some embodiments, the cantilevered regions of cooling element 420 are driven out of phase. In some embodiments, a simple cooling element such as cooling element 120 may be used.

[0066] Anchor 460 supports cooling element 420 from above. Therefore, cooling element 420 is suspended from anchor 460. Anchor 460 is suspended from top plate 410. Top plate 410 includes vent 413. Vent 412 on the side of anchor 460 provides a path for fluid to flow into the side of chamber 440.

[0067] As discussed above with respect to cooling system 100, cooling element 420 can be driven to vibrate at or near its structural resonant frequency. Furthermore, the structural resonant frequency of cooling element 420 can be configured to align with the acoustic resonance of chamber 440 / 1050. The structural and acoustic resonant frequencies are generally chosen to be within the ultrasonic range. For example, the vibrational motion of cooling element 420 can be at the frequencies described with respect to cooling system 100. Therefore, efficiency and flow rate can be improved. However, other frequencies can be used.

[0068] Cooling system 400 operates in a manner similar to cooling system 100. Cooling system 400 therefore shares the benefits of cooling system 100. Consequently, the performance of devices employing cooling system 400 can be improved. Furthermore, suspending cooling element 420 on anchor 460 further enhances performance. In particular, vibrations in cooling system 400 that could affect other cooling cells (not shown) can be reduced. For example, less vibration can be induced in top plate 410 due to the movement of cooling element 420. Therefore, crosstalk between cooling system 400 and other cooling systems (e.g., other cells) or other parts of the device incorporating cooling system 400 can be reduced. Thus, performance can be further enhanced.

[0069] Figures 5A-5E An embodiment of an active cooling system 500 is described, which includes multiple cooling cells configured as tiles or arrays. Figure 5A The top view is depicted, while Figure 5B-5E A side view is depicted. Figures 5A-5E Not drawn to scale. Cooling system 500 includes four cooling cells 501A, 501B, 501C, and 501D (collectively or commonly referred to as 501), which are similar to one or more cooling systems described herein. More specifically, cooling cell 501 is similar to cooling systems 100 and / or 400. Although four cooling cells 501 in a 2x2 configuration are shown, other numbers and / or other configurations of cooling cells 501 may be used in some embodiments. In the illustrated embodiment, cooling cell 501 includes a shared top plate 510 with orifices 512, cooling elements 520, a shared perforated plate 530 including orifices 532, a top chamber 540, a bottom chamber 550, and anchors (support structures) 560, which are similar to a top plate 110 with vents 112, cooling elements 120, a perforated plate 130 with orifices 132, a top chamber 140, a bottom chamber 150, and anchors 160. In some embodiments, cooling cells 501 may be manufactured together and separated, for example, by cutting through the top plate 510, the sidewalls between cooling cells 501, and the perforated plate 530. Thus, although described in the context of a shared top plate 510 and a shared perforated plate 530, cooling cells 501 can be separated after manufacturing. In some embodiments, tabs (not shown) and / or other structures such as anchors 560 may connect cooling cells 501. Furthermore, the cooling system 500 may be attached to a heat-generating structure (e.g., a heat sink, integrated circuit, or other structure), which may be part of an integrated system including the cooling system 500 or may be detachable from the cooling system 500. Additionally, shrouds or other mechanisms may be included for directing fluid flow to the exterior of the cooling cells 501, for mechanical stability, or for protection. Electrical connections to the cooling cells 501 are also not specified. Figures 5A-5E As shown in the diagram, the cooling element 520 is driven in a non-phase manner (i.e., in a seesaw-like manner). Furthermore, as... Figures 5B-5C and Figure 5D-5E As can be seen, the cooling element 520 in one cell is driven in a different phase than the cooling elements 520 in (multiple) adjacent cells. Figures 5B-5C In this configuration, the cooling elements 520 in a row are driven in opposite phases. Therefore, the cooling element 520 in cell 501A is out of phase with the cooling element 520 in cell 501B. Similarly, the cooling element 520 in cell 501C is out of phase with the cooling element 520 in cell 501D. Figure 5D-5E In this system, the cooling elements 520 in one column are driven in opposite phases. Therefore, the cooling element 520 in cell 501A is in opposite phases to the cooling element 520 in cell 501C. Similarly, the cooling element 520 in cell 501B is in opposite phases to the cooling element 520 in cell 501D. By driving the cooling elements 520 in opposite phases, vibration in the cooling system 500 can be reduced.

[0070] The cooling cells 501 of the cooling system 500 operate in a manner similar to or analogous to the cooling systems 100, 400 and / or similar systems. Therefore, the benefits described herein can be shared by the cooling system 500. Vibration in the cooling system 500 is reduced due to the out-of-phase driving of the cooling elements in adjacent cells. The cooling system 500 enjoys enhanced cooling capacity due to the use of multiple cooling cells 501. Furthermore, multiple individual cooling cells 501 and / or the cooling system 500 can be combined in various ways to achieve the desired footprint of the cooling cells.

[0071] Figure 6 This is a flowchart depicting an embodiment of a method 600 for forming (multiple) cooling systems using sheet layer manufacturing. For simplicity, not all steps are shown. Furthermore, the steps may be performed in other orders, include sub-steps, and / or be combined. Method 600 is primarily described in the context of manufacturing multiple cooling systems. However, a single cooling system may be formed.

[0072] At 602, multiple sheets of various structures for a cooling system are provided. Each sheet includes at least one structure for a level in each cooling cell. Each sheet also generally includes multiple structures for multiple cooling cells. A specific level of a cooling cell includes a cooling element having a first side and a second side. Once the multiple cooling cells are manufactured, the cooling element is configured to undergo vibratory motion to drive fluid from the first side to the second side. For example, as part of 602, an active element sheet may be formed. The active element sheet includes a cooling element and is located at a specific level of a cooling cell. Thus, as part of forming the active element sheet at 602, a substrate and multiple piezoelectric layers for cooling elements such as cooling elements 120, 420, and / or 520 may be provided for each cell. Similarly, as part of 602, a perforated plate sheet including a perforated plate for each cell and / or a top plate sheet including a top plate for each cell may be provided. Therefore, perforated plates 130, 430, and / or 530 and top plates 110, 410, and / or 510 can be formed. At 602, structures are also provided in and / or on the sheets. Thus, cavities, trenches, through holes, tapered shapes, and other features can be etched into various sheets. For example, orifices can be formed for each perforated plate in a perforated plate sheet. Vents can be formed in each top plate of a top plate sheet. Stepped regions, extension regions, and outer regions of simple cooling elements and / or engineered cooling elements can be formed for each cooling element in an active element sheet. In some embodiments, as part of 602, anchors are formed from the active element sheet. For example, a substrate for the sheet can be etched to form the anchors and cooling elements. Alternatively, anchors can be formed separately from different sheets. As part of 602, piezoelectric layers, insulating layers, conductive layers, and / or other components can also be fabricated on the sheets. In some embodiments, some or all of such structures can be provided on the corresponding sheets after the sheet has been attached to one or more other sheets. Therefore, at 602, cooling elements, anchors, perforated plates, top plates, orifices, vents, chamber walls, and / or other structural features may be formed. In some embodiments, at 602, a structure for a single cell is formed individually. In some embodiments, at 602, a structure for multiple cells is formed. For example, at 602, a single large perforated plate including multiple sets of orifices may be provided for multiple cells. The sheets manufactured at 602 are independent and, in some embodiments, are physically separate. Therefore, each sheet manufactured at 602 can be separated from other sheets.

[0073] At 604, the sheets are aligned. At 606, the sheets are attached to form cooling cells. In some embodiments, at 606, the sheets are laminated to form a larger sheet comprising multiple cooling cells. Processes 604 and 606 may be performed alternately. For example, the active element sheet may be aligned with the orifice plate sheet at 604 and the two sheets may be attached at 606. In some embodiments, portions of the chamber wall for individual cells are fabricated on the orifice plate sheet and / or the top plate sheet. In some embodiments, the frame and / or additional components forming the chamber wall are aligned at 604 and mounted on the orifice plate sheet and / or the active element sheet at 606. At 604 and 606, the top plate sheet is aligned and mounted to the cooling element or frame sheet. Thus, layers for cooling cells are aligned and assembled. Other configurations and sequences of the sheets are possible.

[0074] In some embodiments, at 606, epoxy resin, welding, and / or other types of adhesives and / or processes are used to attach the layers. In some embodiments, liquid epoxy resin may be dispensed and cured. In some embodiments, a mold is used to align and attach the layers of the cooling system. In some embodiments, at 606, various adhesives are used to attach the components of the cooling cells. The adhesive may include fillers to provide desired properties. For example, the adhesive may include conductive fillers, fillers that increase Young's modulus, fillers for controlling the height of the formed cooling cells, and / or fillers for other purposes. In some embodiments, welds may be used to attach some or all of the structure. For example, lines, dots, and / or combinations of patterns of welds, as well as filler welds, filler welds, through welds, and / or other welds may be used. Thus, at 606, a laminate comprising a plurality of laminated cooling cells may be formed.

[0075] At 608, the cooling cell is optionally separated into multiple segments. Each segment includes at least one cooling cell. For example, if a large sheet comprising multiple cooling cells is formed at 606, individual cells (e.g., cooling system 100) or panels (e.g., cooling system 500) can be cut from the sheet at 608. Thus, at 608, a 2x2 array of cells can be formed. In some embodiments, at 608, arrays of cells(s) of other sizes can be separated. 608 can be performed, for example, to separate individual cells, 4x4 arrays of cells, and / or other configurations from the sheet. Cells within a panel can be separated from each other to improve vibration isolation. For example, orifices and / or top plates may be connected only by tabs. In some embodiments, 608 includes laser-cutting of panels and / or cells. In some embodiments, 608 may include additional cuts for other purposes such as vibration isolation.

[0076] Using method 600, cooling systems, tiles, and / or cooling cells, such as 100, 400, 500, and / or 501, can be formed. Therefore, the benefits of such cooling systems, tiles, and / or cooling cells can be realized. Furthermore, manufacturing is simplified, and large quantities of tiles and / or cooling cells can be easily produced on a scale.

[0077] For example, Figures 7A-7G An embodiment of a lamination cooling system during manufacturing using method 600 is depicted. For simplicity, only some components are shown, and not all discussed structures are labeled. In other embodiments, other components and / or other arrangements may be used. Figures 7A-7G It is not drawn to scale. Although a specific number of cooling cells are shown, the sheet and / or laminate may include other numbers of cooling cells. Figure 7A , Figures 7B-7C and Figure 7D A top plate sheet 710, an active element sheet 721, and an orifice plate sheet 730 are depicted. In some embodiments, the top plate sheet 710, the active element sheet 721, and / or the orifice plate sheet 730 may comprise or be sheets at least fifty micrometers thick and no more than one millimeter thick before processing. For example, the sheets (such as the active element sheet 721) may comprise or be composed of one or more of steel, Al (e.g., Al alloys), and / or Ti (e.g., Ti alloys such as Ti6Al-4V). Figure 7A The top plate sheet 710 is a top plate sheet. Therefore, as part of 602, the vent 712 has been formed in the top plate sheet 710. For example, the vent 712 may be etched into the top plate sheet 710. Figure 7D A perforated sheet 730 formed at 602 is depicted. Therefore, orifices 732 have been etched into the perforated sheet 730. Two sets of orifices 732 are formed for each cooling cell to be provided. In some embodiments, other structures may be formed in or on the top sheet 710 and / or 720.

[0078] Figure 7B and Figure 7C A cross-sectional view and a top view of the active element sheet 721 formed at 602 are depicted. Therefore, a cooling element 720 and an anchor 760 are formed as part of 602. Apertures 725 are also formed. Therefore, the cooling element 720 and the anchor 760 are part of an integrated structure. Therefore, the active element sheet 721 can be selectively etched to form the anchor 760, the cooling element 720, and the apertures 725 separating the cooling element 720 from the cooling cell walls. Figures 7B-7C Only a portion of the cooling element 720 formed from the active element sheet 721 is explicitly depicted. For example, the piezoelectric element and / or other structures used to drive the cooling element 720 are not shown. Figures 7B-7C As shown in the image. Figure 7C As can be seen, a large number of cooling elements 720 can be formed from the same active element sheet 721. Figure 7C In the illustrated embodiment, the cooling elements 720 are formed as groups 724 to facilitate the formation of a tile such as the cooling system 500. Thus, four cooling elements 720 are formed as groups 724 for use in a four-cell tile such as the cooling system 500. The top plate sheet 710 and the perforated plate sheet 730 may also have a structure formed as groups similar to group 724. In the illustrated embodiment, the perforations 725 are etched through and therefore... Figure 7C Shown in black. The outline of group 724 and the boundaries between the cooling elements 720 of the different cells in group 724 may be partially etched through or otherwise defined to facilitate the separation of group 724 and individual cells later in manufacturing.

[0079] Figure 7C Tabs 726 are also depicted. Tabs 726 mechanically connect individual cells within group 724 or cladding. In the illustrated embodiment, tabs 726 are outside the occupied area of ​​group 724. In other embodiments, tabs may be located within the occupied area of ​​group 724. For example, tabs may be located directly between cooling elements 720 within group 724. Although shown only with respect to active element sheet 721, tabs 726 may be part of multiple sheets, including but not limited to top plate sheet 710 and perforated plate sheet 730. Furthermore, some or all of tabs 726 may be removed later in manufacturing. In some embodiments, tabs 726 are retained in the final device and provide additional mechanical stability.

[0080] Figure 7E The image depicts a top plate sheet 710, an active element sheet 721, and a perforated plate sheet 730 aligned at 606, with a laminate 700 attached thereafter at 608. Figure 7EA frame 780 is also shown for spaced between the top plate sheet 710 and the active element sheet 721. Although not shown, piezoelectric layers, electronics, and / or other components for actuating the cooling element 720 are also provided. In some embodiments, as part of 602, these components are formed before the active element sheet 721 is aligned and attached to the perforated plate sheet 730 and / or the top plate sheet 710. In some embodiments, as part of 602, these components are formed after the active element sheet 721 is aligned and attached to the perforated plate sheet but before the top plate sheet 710 is added. Epoxy resin or multiple other adhesives (including welds) 770 for attaching the top plate sheet 710, the active element sheet 721, the perforated plate sheet 730, and the frame 780 are also shown. The coefficients of thermal expansion (CTE) of the active element sheet 721, the perforated plate sheet 730, and (in some embodiments) the epoxy resin 770 used to attach the active element sheet 721 and the perforated plate sheet 730 can be closely matched. For example, the CTE can be matched to within 10 percent in some embodiments, and to within 5 percent in some such embodiments. Such CTE can improve the geometric control of the cooling cell being manufactured and reduce stress between the structures of the active element sheet 721 and the perforated plate sheet 730. Dashed lines indicate separable areas of the cooling cell. For example, cutting, such as laser cutting, can be performed at or near the dashed lines. In some embodiments, at least some of the pores defining individual cells already exist. For example, pre-existing pores define... Figure 7C Group 724 is shown. Therefore, the laminate 700 includes a plurality of fabricated, aligned and attached sheets to form a cooling cell.

[0081] Figure 7F Another embodiment of the laminate 700' is depicted. The laminate 700' includes: a top plate sheet 710 including a vent 712, a frame 780, an active element sheet 721 having a cooling element 720, a perforated plate sheet 730 having orifices 732, and epoxy resin or (a plurality of) other adhesives 770. Dashed lines indicate areas that can be separated into individual cells, for example, by laser or other cutting. Anchors 760' are also shown, formed therefrom. Thus, anchors 760' are attached to the perforated plate sheet 730 via epoxy resin or (a plurality of) other adhesives 770. Anchors 760' are attached to the active element sheet 721 via epoxy resin 770' or other adhesives. The laminate 700' thus includes a plurality of cooling cells, wherein the anchors 760' are individually manufactured as sheets and bonded to the active element sheet 721.

[0082] Figure 7GAnother embodiment of the laminate 700'' is depicted. The laminate 700'' includes: a top plate sheet 710 including a vent 712, a frame 780, an active element sheet 721 having a cooling element 720, a perforated plate sheet 730 having orifices 732, and epoxy resin or (a plurality of) other adhesives 770. Dashed lines indicate areas that can be separated into individual cells, for example, by laser or other cutting. Instead of anchoring sheets or integrated anchors, epoxy resin and / or (a plurality of) other adhesives are formed Anchors 760 / 770''. The laminate 700' therefore includes multiple cooling cells, wherein anchors 760' are formed individually during the bonding of the active element sheet 721 and the perforated sheet 730. In another embodiment, the anchors may be formed from the perforated sheet 730. For example, the perforated sheet 730 may be etched to not only form the orifice 732, but also remove material around the area where the anchor is to be formed. In some embodiments, the anchoring structure may be fabricated on the perforated sheet 730 in other ways.

[0083] Therefore, laminated cooling cells and / or cooling tiles can be formed. This allows for the realization of the benefits of such cooling systems, tiles, and / or cooling cells. Furthermore, manufacturing is simplified, and large quantities of tiles and / or cooling cells can be easily produced on a scale.

[0084] Figures 8A-8C These figures depict embodiments of cooling systems 800A, 800B, and 800C, illustrating manufacturing using sheet-layer lamination. Therefore, cooling systems 800A, 800B, and 800C are laminated cooling systems. For simplicity, only some components are shown, and not all discussed structures are labeled. In other embodiments, other components and / or other arrangements may be used. Figures 8A-8C Not drawn to scale. Cooling systems 800A, 800B, and 800C may also be part of a tiling such as cooling system 500. Cooling systems 800A, 800B, and 800C can therefore be considered as laminated cooling cells.

[0085] Figure 8A A cooling system 800A is depicted. The cooling system 800A includes a top plate 810 with orifices 812, a cooling element 820, an orifice plate 830 including openings, a top chamber, a bottom chamber, and anchors (support structures) 860, which are similar to a top plate 110 with vents 112, a cooling element 120, an orifice plate 130 with openings 132, a top chamber 140, a bottom chamber 150, and anchors 160. The location of a heat-generating structure 802 intended for use with the cooling system 800A is indicated by dashed lines.

[0086] like Figure 8AAs can be seen, a multi-layered structure has been fabricated, attached, and, in some embodiments, separated to form the cooling system 800A. Therefore, in addition to the structures described above, bonding layers 880, 882, 884, and 886 are also shown. Such bonding layers are used to attach structures such as the perforated plate 830, the frame 870, and the top plate 810. In some embodiments, the frame 870 is nominally one hundred micrometers thick. However, other thicknesses may be used. A bonding layer 824 for the cooling element 820 is also shown, which may be formed at 602 and is used to attach the piezoelectric element 826 to the substrate 822. In some embodiments, the substrate 822 may be stainless steel, an Al alloy (including only Al), and / or a Ti alloy such as Ti6Al-4V. When the piezoelectric element 826 is actuated, the substrate 822 can be considered to be bent. Therefore, in some embodiments, the substrate 822 is considered to be an actuator for the cooling element 820. In some embodiments, all of the elements in the cooling element 820 can be considered to be actuators. Bonding layers 824, 880, 882, 884, and / or 886 can be formed using epoxy resin adhesives. Such epoxy adhesives can have a high modulus. In some embodiments, the epoxy adhesive can be applied as a film or sheet, dispensed as a liquid via needle, screen printing, inkjet, or spraying. Thermosetting or UV-cured epoxy resins can also be used. Other adhesives, such as pressure-sensitive adhesives, acrylic adhesives, etc., can also be used.

[0087] In some embodiments, the adhesive can be filled to customize properties. For example, fillers can be used to adjust thermal conductivity, electrical conductivity, thickness (e.g., bonding height), modulus, and / or other properties. Figure 8B A cooling system 800B, similar to a cooling system 800, is depicted. The cooling system 800B includes components similar to those in the cooling system 800. Such components have similar markings. Furthermore, filler joints 882B and 824B, similar to bonding layers 882 and 824, are shown respectively. Filler joint 882B includes filler for controlling the height of the cooling system 800B. Filler joint 824B includes conductive filler. Therefore, a piezoelectric element 826 can be electrically connected to filler joint 824B. Additionally, filler joint 824B can be electrically connected to substrate 822.

[0088] In some embodiments, one or more structures may be welded. For example, cooling system 800C depicts a cooling cell in which welded sections are used to attach anchors to an orifice plate, to a cooling element, and to a chamber wall. Figure 8CThe diagram also indicates the areas where the patterns of weld portions 890 and 892 are formed. In the illustrated embodiment, the higher-density weld portion 890 is used for the anchor 860. The lower-density weld portion 892 can be used for the edges (walls) of the cooling systems 800A and / or 800B. Welding may be desirable because it produces a joint with higher mechanical strength. Figure 8C As indicated, different solder joint patterns can be used to mitigate heat and substrate deformation.

[0089] Figures 8A-8C The formation of the system shown can be performed using method 600. Furthermore, multiple cooling systems can be formed together. For example, for cooling system 800, at 602, the substrate 822 of cooling element 820, bonding layer 824, and piezoelectric element 826 can be formed in a sheet. Also at 602, an anchor 860 can be formed by removing a portion of the substrate 822. In such an embodiment, the anchor 860 is integrated into the cooling element 820. If the cooling element 820 has a shape similar to cooling element 120', the substrate 822 can be etched to form stepped regions, extended regions, and outer regions. Since multiple cooling elements 820 can be formed in a sheet, multiple anchors 860 are formed at 602. Also at 602, individual cooling elements 820 can be separated from the sheet for assembly. In some embodiments, the cooling elements are separated later during manufacturing. Also at 602, orifices in a perforated plate 830 can be formed. The perforated plate 830 can also be formed in a sheet including multiple sets of orifices corresponding to the perforated plate 830. At 602, apertures 812 in the top plate 810 may also be provided. The top plate 810 may also be formed in a sheet including a plurality of apertures 812 corresponding to the top plate 810. At 604 and 606, the structure is aligned and attached to its desired location. In some embodiments, individual cooling elements 820 are aligned with the area between the apertures and attached to the sheet for the aperture plate 830. In some embodiments, the sheet for the cooling elements 820 is aligned and attached, for example, via bonding layers 880 and / or 884. In embodiments where the anchor 860 is not integrated into the cooling element 820, the anchor 860 is attached separately to the sheet containing the aperture plate 830. The sheet may then be etched to separate the cooling elements 820 from the chamber wall. Also at 606, the frame 870 (provided as part of 602) may be attached via bonding layer 886. The sheet containing the top plate 810 is also aligned and attached via bonding layer 882. Then at 608, the individual cooling system 800 or a group of cooling systems (e.g., tilings) can be separated from the sheet. A similar process can be used to manufacture cooling systems 800B and / or 800C.

[0090] Figure 9This is a diagram depicting an embodiment of a cooling system 900 in which the welded parts are used during manufacturing. Therefore, a portion of the cooling system 900 is shown. For simplicity, only some components are shown, and not all discussed structures are labeled. In other embodiments, other components and / or other arrangements may be used. Figure 9 It was not drawn to scale.

[0091] The cooling system 900 includes a cooling element 920, an orifice plate 930, and an anchor 960. A top plate and other structures completing the cooling system 900 are not shown. Furthermore, orifices similar to orifices 132, 432, 532, 732, and 832 are not shown. More specifically, various welds are used for the anchor 960 and the actuator / cooling element 920. Figure 9 As indicated, laser welding can be used to attach anchors to corresponding holes in the perforated plate. Laser welding filler may also be provided. Cooling element 920 may also be attached to anchor 960 using welds(multiple) welds. In such embodiments, methods 604 and 606 of 600 may include aligning anchor 960 with corresponding holes in the sheet containing the perforated plate, completing various welds, aligning the sheet containing cooling element 920 with its desired position, and completing a weld between anchor 960 and cooling element 920. Thus, a variety of configurations can be used in a manufacturing cooling cell manufactured via sheet layers.

[0092] Figure 10 This is a flowchart depicting an embodiment of a method 1000 for providing multiple cooling systems using sheet-layer manufacturing. For simplicity, not all steps are shown. Furthermore, the steps may be performed in other orders, include sub-steps, and / or be combined. Method 1000 is primarily described in the context of manufacturing multiple cooling systems. However, a single cooling system may be formed.

[0093] At 1002, each sheet is selectively etched to form a desired structure. For example, areas of the sheet can be masked and etched to form pores therein. The mask can be removed and replaced, and the sheet etched to change the sheet thickness. Such variations in thickness can be used to provide structures or other features such as anchors. Furthermore, since the sheets are physically separable, only the top, only the bottom, or both the top and bottom of the sheet can be etched. For example, pores in the top sheet can be formed by etching the sheet from both sides. Similarly, engineered cooling elements with variations in both the top (facing the top plate) surface and the bottom (facing the perforated plate) surface can be formed.

[0094] At 1004, additional components for each sheet are provided on the sheets. For example, a piezoelectric layer, a seed layer, and / or other electrical connection layers may be provided on the active element sheet. Since the sheets are physically separable, structures may be provided on the top and / or bottom of the sheets. In some embodiments, 1002 and 1004 are performed when a particular sheet is free. In some embodiments, 1002 and / or 1004 may be performed when a sheet is attached to another sheet. Thus, 1002 and 1004 can be considered to correspond to 602 of method 600.

[0095] At point 1006, the fabrication of the laminate is completed. For example, each sheet can be aligned and attached to the remaining sheets(s), individual cells and / or collages can be separated, and / or additional structures can be formed.

[0096] Figure 11A-11D An embodiment of a lamination cooling system during manufacturing using method 1000 is depicted. Specifically, active element sheet 1121 is shown. For simplicity, only some components are shown, and not all discussed structures are labeled. In other embodiments, other components and / or other arrangements may be used. Figure 11A-11D It is not drawn to scale. Although a specific number of cooling cells are shown, the sheet and / or laminate may include other numbers of cooling cells.

[0097] Figure 11A The active element sheet 1121 before processing is depicted. In some embodiments, the active element sheet 1121 is a stainless steel sheet, an Al alloy sheet, or a Ti alloy sheet such as Ti6Al-4V. Figure 11B An active element sheet 1121 is depicted after forming a aperture 1125 as part of 1002. The aperture 1125 separates the formed cooling element from the walls of the cooling cell. However, in some embodiments, a portion of the cooling element (not shown) remains connected. The aperture 1125 can be fabricated by etching the top and / or back sides of the active element sheet 1121. Figure 11C The active element sheet 1121, as part of 1002, is depicted after further etching. Anchor 1160 is thus formed. Additionally, an engineered cooling element 1120 with varying thickness is manufactured. Therefore, portions of the back side of the active element sheet 1121 can be etched to form the cooling element 1120 and / or the anchor 1160. Figure 11D The active element sheet 1121 is depicted after the piezoelectric layer 1127 is provided as part of 1004. Other structures may also be provided as part of 1004. At 1006, a laminated cooling cell (not shown) comprising the active element sheet 1121 is formed.

[0098] Therefore, the sheet material can be manufactured and integrated into laminated cooling cells and / or laminated cooling tilings. This allows for the realization of the benefits of such cooling systems, tilings, and / or cooling cells. Furthermore, manufacturing is simplified, and large-scale production of tilings and / or cooling cells is easily achieved.

[0099] Figure 12A-12D Embodiments of portions of cooling elements 1200A, 1200B, 1200C, and 1200D are depicted, illustrating a fabrication process that allows for electrical connection of the substrate to the electrodes. For example... Figure 12A As seen in 12B, 12C, and 12D, cooling elements 1200A, 1200B, 1200C, and 1200D each respectively include at least a first insulator 1220, a stainless steel, Al alloy, and / or Ti alloy substrate 1210 (e.g., a sheet), and second insulators 1230A, 1230B, 120C, and 1230D. Cooling elements 1200A, 1200B, 1200C, and 1200D also include electrodes (e.g., bottom electrodes) 1240A, 1240B, 1240C, and 1240D, which can also be used as seed layers for piezoelectric layers 1250A, 1250B, 1250C, and 150D, respectively. Cooling element 1200B includes an additional conductive layer 1260B. To form an electrical contact between the substrate 1210 and the electrode 1240C, the cooling element 1200C includes a metal layer 1270C or a jumper. To ensure contact between the substrate 1210 and the electrode 1240C, a portion of the insulator 1230C is removed. In the cooling element 1200D, this electrical contact is achieved by forming a through-hole in the second insulator 1230D prior to the deposition of the electrode layer 1240D. Therefore, the substrate 1210 can be electrically connected to the bottom electrodes 1240A, 1240B, 1240C, or 1240D.

[0100] Laminated sections comprising multiple cooling elements formed from sheets can be manufactured. Individual laminated cooling cells and / or laminated panels can be separated from the laminate. Therefore, the benefits of such cooling systems, panels, and / or cooling cells can be realized while simplifying manufacturing. Such manufacturing also allows for easy scale-up production of large quantities of panels and / or cooling cells. This improves the performance and manufacturing of the cooling cells.

[0101] Although the foregoing embodiments have been described in detail for clarity of understanding, the invention is not limited to the details provided. Many alternative ways of carrying out the invention exist. The disclosed embodiments are exemplary and not restrictive.

Claims

1. A method for providing a cooling system, comprising: A plurality of sheets are provided, each of the plurality of sheets including at least one structure for a layer in each of a plurality of cooling cells, wherein a particular layer of each of the plurality of cooling cells includes a cooling element having a first side and a second side, the cooling element being configured to undergo a vibratory motion to drive fluid from the first side to the second side. Align the plurality of sheets; The plurality of sheets are attached to form a laminate, the laminate including the plurality of cooling cells; as well as The laminate is divided into multiple segments, each of which includes at least one of the multiple cooling cells.

2. The method according to claim 1, wherein, The provision of the plurality of sheets further includes: A perforated plate sheet is provided, the perforated plate sheet having a plurality of orifices therein; An active element sheet is provided, the active element sheet comprising the cooling element for each of the plurality of cooling cells, the cooling element having a central region and a periphery, at least a portion of the periphery being freely subjected to the vibratory motion; and A top plate sheet is provided, the top plate sheet including at least one vent for each of the plurality of cooling cells.

3. The method according to claim 2, wherein, The alignment further includes: The active element sheet is placed between the top plate sheet and the perforated plate sheet.

4. The method according to claim 2, wherein, The provision of the plurality of sheets further includes: A frame sheet is provided, a portion of which forms a cell wall for each of the plurality of cooling cells.

5. The method according to claim 4, wherein, The appendix further includes: The plurality of sheets are attached such that the active element sheet is attached to the perforated plate sheet, the frame sheet is attached to the active element sheet or the top plate sheet, and the top plate sheet is attached to the frame sheet or is attached to the frame sheet in the same way as it is attached to the active element sheet.

6. The method according to claim 2, wherein, The provision of the active element sheet further includes: Selectively etching a substrate to provide multiple regions with multiple heights, said substrate comprising at least one of stainless steel, Al alloy, and Ti alloy; and A piezoelectric layer is provided on a portion of the substrate.

7. The method according to claim 6, wherein, The provision of the active element sheet further includes: An insulating barrier is provided on the substrate; A bottom electrode is provided on the insulating barrier, and the piezoelectric layer is located on the bottom electrode; and Connecting the bottom electrode to the substrate, the connection of the bottom electrode includes a process selected from: providing a jumper between the bottom electrode and the substrate, and providing at least one through-hole in the insulating barrier prior to providing the bottom electrode.

8. The method according to claim 2, wherein, Providing the active element sheet further includes: a support structure defined from a portion of the active element sheet for the cooling element, the support structure being located at a central region of the cooling element, the support structure being configured to be attached to another sheet of the plurality of sheets such that at least a portion of the periphery undergoes a vibrational movement relative to the central region of the cooling element in response to actuation of the cooling element.

9. A cooling system manufactured by the method according to any one of claims 1-8, comprising: A laminated cooling cell comprising multiple sheets, each of the multiple sheets including at least one structure for a layer in the laminated cooling cell, wherein an active element plate in the multiple sheets includes a cooling element having a first side and a second side, the cooling element being configured to undergo vibratory motion to drive fluid from the first side to the second side.

10. The cooling system according to claim 9, wherein, The plurality of sheets further include: A perforated sheet having a plurality of openings therein; and A top plate sheet having at least one vent therein, an active element sheet located between the perforated plate sheet and the top plate sheet, and a cooling element having a central region and a periphery configured to undergo the vibrational motion.

11. The cooling system according to claim 10, wherein, The active element sheet further includes a support structure at the central region of the cooling element, the active element sheet being connected to the perforated plate sheet by the support structure, such that at least a portion of the periphery undergoes a vibrational movement relative to the central region of the cooling element in response to actuation of the cooling element.

12. The cooling system according to claim 10, wherein, The plurality of sheets further include: A frame sheet, a portion of which forms the cell wall for the laminated cooling cell.

13. The cooling system according to claim 12, wherein, The frame sheet is located between the active element sheet and the top plate sheet.

14. The cooling system according to claim 10, wherein, The active element sheet further includes a piezoelectric layer.

15. The cooling system according to claim 14, wherein, The cooling element further includes: A substrate, the substrate comprising at least one selected from stainless steel, Al alloy and Ti alloy; The insulating barrier on the substrate; The bottom electrode is located on the insulating barrier, and the piezoelectric layer is situated on the bottom electrode; and The electrical connector between the bottom electrode and the substrate.

16. A cooling system manufactured by the method according to any one of claims 1-8, comprising: The plurality of laminated cooling cells comprise multiple sheets, each of the plurality of sheets comprising at least one structure for a layer in the laminated cooling cell of the plurality of laminated cooling cells, the plurality of sheets further comprising: A perforated sheet having a plurality of openings therein for each of the plurality of laminated cooling cells; An active element sheet comprising a cooling element for each of the plurality of laminated cooling cells, the cooling element having a first side and a second side, the cooling element configured to undergo vibratory motion to drive fluid from the first side to the second side; and A top plate sheet having at least one vent for each of the plurality of laminated cooling cells, the active element sheet being located between the perforated plate sheet and the top plate sheet.

17. The cooling system according to claim 16, wherein, The cooling element has a central region and at least one cantilever, which undergoes the vibrational motion.

18. The cooling system according to claim 16, wherein, The plurality of sheets further include: A frame sheet, a portion of which forms the cell wall for each of a plurality of laminated cooling cells.

19. The cooling system according to claim 18, wherein, The frame sheet is located between the active element sheet and the top plate sheet.

20. The cooling system according to claim 18, wherein, The cooling element has a central region and a periphery, and the active element sheet further includes: A support structure for the cooling element, the support structure being located at the central region of the cooling element, the support structure being coupled to the perforated plate, such that at least a portion of the periphery undergoes a vibrational movement relative to the central region of the cooling element in response to actuation of the cooling element.

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