Method to transfer heat from small form factor pluggable connector to remote heat sink

Abstract

An apparatus for distributing heat from a component in a computing system such as a small form-factor pluggable (SFP) connector may include a heat distribution means configured to receive excess heat from the component and to transfer the excess heat to a distant cooling medium. The heat distribution means may include solid blocks of heat conducting material such as copper, heat pipes, and liquid loops. The apparatus includes an attachment means for securing the position of the heat distribution means relative to the component. A floating ride-on plate ensures continuous contact with a surface of the component, and a thermal interface material ensures proper heat transfer between the floating ride-on plate and the heat distribution means.

Description

METHOD TO TRANSFER HEAT FROM SMALL FORM FACTOR PLUGGABLE CONNECTOR TO REMOTE HEAT SINKCROSS-REFERENCE TO RELATED APPLICATION

[0001] This Application claims the benefit of provisional U.S. Application No. 63 / 625,548, filed on January 26, 2024, and entitled “METHOD TO TRANSFER HEAT FROM SMALL FORM FACTOR PLUGGABLE CONNECTOR TO REMOTE HEAT SINK” which is hereby incorporated by reference in its entirety.

[0002] In cases where the present application conflicts with a document incorporated by reference, the present application controls.BACKGROUND

[0003] As feature sizes and transistor sizes have decreased for computing hardware such as integrated circuits (ICs) including chips and semiconductor dies, the amount of heat generated by a single chip, such as a microprocessor, has increased. Computing hardware that has traditionally been air cooled has evolved to levels of power consumption requiring more heat dissipation than can be provided by air alone. In some cases, immersion cooling of ICs in a tank containing a coolant fluid is employed to maintain ICs at appropriate operating temperatures.

[0004] One type of immersion cooling is two-phase immersion cooling, in which heat from a semiconductor die is high enough to boil the coolant fluid. The boiling creates a coolant fluid vapor in the tank, which is condensed by cooling coils back to liquid form. Heat from the semiconductor dies can then be sunk into the liquid-to-gas and gas-to-liquid phase transitions of the coolant fluid with the result that the semiconductor dies are kept at an acceptable temperature.

[0005] In many immersion cooling systems, space within an immersion cooling tank is limited. Total submersion in immersion cooling fluid is typically reserved for computing hardware such as graphics processing units (GPUs) in order to maximize computational density. However, other components may still generate significant amounts of heat that must be dissipated to ensure proper operation. No present solution exists to utilize thegreatly improved heat transfer capability of two-phase immersion cooling liquid for components that are not totally submerged in the immersion cooling liquid.SUMMARY

[0006] Transceivers, such as QSFPs (Quad Small Form-Factor Pluggable) and OSFPs (Octal Small Form-Factor Pluggable), are commonly housed within Small Form-Factor Pluggable (SFP) cages. These cages may employ air-cooled ride-on heat sinks without a thermal interface material due to the hot-swappable nature of the transceivers. Network data transfer capacities have rapidly grown in recent years, and this increased data throughput means network components including SFPs are exposed to increasing heat loads from data transfer waste heat.

[0007] When the cooling capacity of ride-on heat sinks is exceeded (usually constrained by the space atop the SPF cages), remote heat sinks with better cooling capability are introduced to dissipate the heat in a space away from the SFP. Various heat transfer mechanisms, including copper slabs, heat pipes, or liquid loops, may be employed to establish a heat transfer pathway from the SFP to the remote heat sink. However, the rigidity or lack of flexibility (floating) in these heat transfer devices may result in inadequate surface contact with the transceiver module within the SFP cage, leading to suboptimal thermal resistance and the potential overheating of transceivers.

[0008] In an aspect, the present technology may combine a floating ride-on plate, a thermal interface material (TIM), and a long-distance heat transfer device (LDHTD) to establish an effective heat transfer pathway from a hot-swappable transceiver module in an SFP cage to a remote heat sink. The ride-on plate, which may be made of high thermal conductivity materials like copper or aluminum, captures heat from the transceiver module in the SFP cage. The heat then conducts through a thermal interface material to the LDHTD before reaching the remote heat sink. The ride-on plate may be designed to “float” relative to the LDHTD since it isn't fixed to the rigid LDHTD, ensuring an optimal surface contact with the transceiver top surface.

[0009] To apply contact pressure, an attachment means generates a downward force. In an embodiment, an attachment means may include a backing plate with spring clips configured to interface with hooks on the SFP cage. The TIM serves to absorb any variations in surface contact between the ride-on plate and LDHTD, providing anappropriate thermal interface. Importantly, as the TIM doesn't directly interface with the hot-swappable transceivers, the TIM doesn't need to withstand frequent abrasion, mitigating potential reliability challenges.

[0010] The present technology includes a combined floating ride-on plate, a thermal interface material, a long-distance heat transfer device and mechanical retention structure to form an effective heat transfer pathway from a hot swappable transceiver module in a SFP cage to a remote heat sink.

[0011] In some aspects, the techniques described herein relate to an apparatus for transferring heat, the apparatus including a heat distribution means configured to distribute heat from a component to a cooling medium; a thermal interface material disposed in thermal contact with at least one surface of the heat distribution means and at least one surface of a floating ride-on plate, wherein the floating ride-on plate is in thermal contact with the component; and an attachment means configured to secure a position of the heat distribution means relative to the component.

[0012] In some aspects, the techniques described herein relate to an apparatus, wherein the attachment means does not directly contact the heat distribution means.

[0013] In some aspects, the techniques described herein relate to an apparatus, further including a backing plate disposed in physical contact with the heat distribution means and attachment means; and wherein the backing plate is configured to transfer a force from the attachment means to the heat distribution means.

[0014] In some aspects, the techniques described herein relate to an apparatus, wherein the heat distribution means includes one or more of a heat pipe, a liquid loop, or a solid block.

[0015] In some aspects, the techniques described herein relate to an apparatus, wherein the solid block includes copper, aluminum, or silver.

[0016] In some aspects, the techniques described herein relate to an apparatus, wherein the floating ride-on plate includes copper, aluminum, or silver.

[0017] In some aspects, the techniques described herein relate to an apparatus, wherein the component includes a small form-factor pluggable (SFP) connector.

[0018] In some aspects, the techniques described herein relate to an apparatus, wherein the SFP connector includes a quad small form-factor pluggable (QSFP) connector or an octal small form-factor pluggable (OSFP) connector.

[0019] In some aspects, the techniques described herein relate to an apparatus, wherein the apparatus is disposed inside of an immersion cooling container, and a first end of the heat distribution means is immersed in an immersion cooling fluid.

[0020] In some aspects, the techniques described herein relate to an apparatus, wherein the attachment means secures the position of the heat distribution means relative to the component by exerting a first force on the heat distribution means and a second force on the component; and wherein the second force is substantially equal and opposite to the first force.

[0021] In some aspects, the techniques described herein relate to an apparatus, wherein the attachment means includes at least one of a clip, a screw, a band, a magnet, a bracket, or a bolt.

[0022] All combinations of the foregoing concepts and additional concepts discussed in greater detail below (provided such concepts are not mutually inconsistent) are part of the inventive subject matter disclosed herein. In particular, all combinations of claimed subject matter appearing at the end of this disclosure are part of the inventive subject matter disclosed herein. The terminology used herein that also may appear in any disclosure incorporated by reference should be accorded a meaning most consistent with the particular concepts disclosed herein.BRIEF DESCRIPTIONS OF THE DRAWINGS

[0023] The skilled artisan will understand that the drawings primarily are for illustrative purposes and are not intended to limit the scope of the inventive subject matter described herein. The drawings are not necessarily to scale; in some instances, various aspects of the inventive subject matter disclosed herein may be shown exaggerated or enlarged in the drawings to facilitate an understanding of different features. In the drawings, like reference characters generally refer to like features (e.g., functionally similar and / or structurally similar elements).

[0024] FIG. 1A illustrates a heat transfer apparatus in accordance with the present technology.

[0025] FIG. IB illustrates a front and side view of an attachment means in accordance with the present technology.

[0026] FIG. 2 illustrates a front view of a heat transfer apparatus in accordance with the present technology.

[0027] FIG. 3 depicts aspects of an immersion cooling system for dissipating heat from one or more heat-generating components such as semiconductor die packages via immersion cooling.DETAILED DESCRIPTION

[0028] FIG. 1A illustrates a heat transfer apparatus 100 in accordance with the present technology. The heat transfer apparatus 100 may include a heat distribution means 110 configured to distribute heat from a component 170 to a cooling medium. Heat transfer apparatus 100 may include a floating ride-on plate 120 and a thermal interface material (TIM 130) disposed between and in thermal contact with at least one surface of heat distribution means 110 and at least one surface of floating ride-on plate 120. TIM 130 may be a deformable material configured to conform to a surface of one or more objects in order to improve a transfer of heat between from the one or more objects through the TIM 130. In an embodiment, the positions of heat distribution means 110 and floating ride-on plate 120 may be fixed relative to one another without being in physical contact with one another.

[0029] Heat transfer apparatus 100 may include an attachment means 140 configured to secure heat distribution means 110 relative to component 170, for example through a combination of friction and compression or a rigid mechanical connection such as a screw that fixes heat distribution means 110 to component 170. An attachment means 140 may include a plurality of elements that interface with backing plate 142 to mechanically contact heat distribution means 110 and exert a downward force on heat distribution means 110. Attachment means 140 may include securing mechanism 144 configured to provide a mechanical coupling between backing plate 142 and component 170, and protrusions 146 configured to interface with securing mechanism 144 and hold securing mechanism 144 in place, which in turn holds backing plate 142 in place, which in turn holds heat distribution means 110, floating ride-on plate 120, and TIM 130 in place.

[0030] Heat transfer apparatus 100 may be disposed within an immersion cooling system, the immersion cooling system including an immersion cooling container containing a reservoir of immersion cooling fluid. The immersion cooling system may include computing hardware such as one or more servers, graphics processing units (GPUs), central processing units (CPUs), tensor processing units (TPUs), data processing units (DPUs), microprocessors, field-programmable gate arrays (FPGAs), programmable logic controllers (PLCs), application-specific integrated circuits (ASICs), digital signal processors (DSPs), artificial intelligence (Al) accelerators, memory modules such as a dynamic random access memory (DRAM) module, a static random access memory (SRAM) module, a flash memory module, a solid-state drive (SSD), a non-volatile random access memory (NVRAM) module, a read-only memory (ROM) module (such as a floating-gate ROM, erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), one-time programmable ROM (OTPROM), or the like), any suitable type of memory module, or any suitable computing hardware.

[0031] Heat distribution means 110 may transfer heat through conduction, convection, radiation, or any suitable heat transfer mechanism. Heat distribution means 110 may be a solid block of material (e.g., a block of metal such as copper, aluminum, silver; a slab of carbon-based material such as graphene or graphite; or any suitable solid heat conducting material), a heat pipe, a liquid loop, or any suitable heat transfer mechanism.

[0032] In an embodiment, heat distribution means 110 may be a heat pipe configured to transfer heat from a source such as component 170 to a cooling medium. A heat pipe may be a hollow tube or pipe with one or more wicks (e.g., a substantially cylindrical wire or other material) configured to assist a liquid in moving from one area within the heat pipe to another through capillary action and / or surface tension. A heat pipe may contain a thermal transfer medium such as deionized water that may act to transfer heat through two-phase evaporative cooling. A portion of the heat pipe containing liquid may be disposed adjacent to a heat source. Heat from the heat source may cause the liquid to boil and the boiled vapor may travel through the heat pipe to a cooler portion of the heat pipe. The vapor may recondense into liquid form and transfer heat to the heat pipe and then out to a surrounding medium. The recondensed liquid may travel back down the heat pipe and continue cooling the heat source.

[0033] Additionally or alternatively, heat distribution means 110 may be a liquid loop, which is a heat pipe where the pipe is a continuous loop instead of a pipe having distinct ends.

[0034] Heat distribution means 110 may include a first end and a second end. A first end of heat distribution means 110 may be immersed in an immersion cooling fluid, for example an immersion cooling liquid or an immersion cooling vapor. In an embodiment, a first end of heat distribution means 110 may include a heat sink such as a copper block configured to improve the dissipation of heat from heat distribution means 110 into a cooling medium such as immersion cooling fluid.

[0035] Heat transfer apparatus 100 may include floating ride-on plate 120. Floating ride- on plate 120 may be configured to mechanically and thermally interface with component 170 and may be dimensioned to improve contact (and therefore heat transfer) between the floating ride-on plate 120 and component 170. Floating ride-on plate 120 may provide a more consistent and efficient heat transfer mechanism between heat distribution means 110 and component 170 than physically contacting component 170 with heat distribution means 110.

[0036] In an embodiment, floating ride-on plate 120 may be a solid block of copper, aluminum, silver, graphene, or other material suitable for transferring heat through conduction or other suitable means. Floating ride-on plate 120 may have at least one surface shaped to conform to a corresponding surface of component 170. Floating ride-on plate 120 may be held in place relative to component 170 by an attachment means 140 and backing plate 142 providing a combination of a compressive force and friction. In an embodiment, floating ride-on plate 120 is not rigidly fixed to component 170 but instead is held in place only using friction. Alternatively, floating ride-on plate 120 may be rigidly fixed to component 170 (e.g., through one or more screws, pins, adhesives, guide rails, etc.).

[0037] Heat transfer apparatus 100 may further include a thermal interface material (TIM 130), which may be a pliable or otherwise mechanically compliant material configured to conform to one or more surfaces of an object with which TIM 130 is in contact. TIM 130 may be made of a solid silicone elastomer, graphite, paraffin wax, liquid metal, or other suitable material or may be a paste, gel, grease, or other semi-fluid material. TIM 130 may help to improve transfer of heat from component 170, through floating ride-on plate 120,and into heat distribution means 110, which may keep component 170 at a lower or more optimal operating temperature.

[0038] Heat transfer apparatus 100 may further include an attachment means 140 configured to secure a position of the heat distribution means 110 relative to the component 170. Preferably, attachment means 140 does not directly contact the heat distribution means 110. A front and side view of attachment means 140 are illustrated in FIG. IB. In an embodiment, attachment means 140 may include securing mechanism 144 and protrusions 146. Securing mechanism 144 may be mechanically attached to backing plate 142. Securing mechanism 144 may include springs, tabs (e.g., plastic, metal, or other suitable material), ties, wires, pins, guides, or other suitable connection mechanism. Protrusions 146 may include hooks, bumps, stubs, stumps, or any material affixed to or extending out from component 170 and configured to interface with securing mechanism 144 such that heat transfer apparatus 100 is secured to component 170.

[0039] Attachment means 140 may secure a position of the heat distribution means 110 relative to component 170 by exerting a first force on heat distribution means 110 and a second force on component 170. The second force may be substantially equal and opposite to the first force. Heat distribution means 110 may subsequently exert a force equal to the first force on TIM 130, which in turn exerts an equal force on floating ride-on plate 120, which in turn exerts an equal force on component 170, which is balanced by the second force.

[0040] In an alternative embodiment, backing plate 142 and securing mechanism 144 may be a single contiguous element.

[0041] In an embodiment, attachment means 140 may include one or more clips, screws, bands, magnets, brackets, bolts, or other suitable securing mechanism. Attachment means 140 may attach to backing plate 142 to secure the position of the heat distribution means 110 relative to the component 170. In such an embodiment, protrusions 146 may be omitted as the one or more clips, screws, bands, magnets, brackets, bolts, or other suitable securing mechanisms may work to affix backing plate 142 to heat distribution means 110, floating ride-on plate 120, TIM 130, and component 170.

[0042] Component 170 may include one or more networking connectors such as a small form-factor pluggable (SFP) connector. In an embodiment, an SFP connector may include a quad SFP (QSFP) connector, an octal SFP (OSFP) connector, or any suitable connector.In an additional or alternative embodiment, component 170 may further include one or more processors, memory modules, integrated circuits (ICs; such as logic ICs, memory ICs, or other ICs), three-dimensional integrated circuit (3DIC) stacks, network switches, sensors, baseboard management controllers (BMCs), electrical cables, network cables, passthroughs, or any suitable component that generates heat.

[0043] Component 170 may be mounted to a printed circuit board (PCB 180). For example, component 170 may be an SFP connector mounted to a network card PCB, a server motherboard, a network card PCB, or any suitable PCB. Component 170 may be communicatively, physically, thermally, electrically, and / or mechanically coupled to PCB 180. PCB 180 may be further coupled one or more additional components including one or more processors, memory modules, integrated circuits (ICs; such as logic ICs, memory ICs, or other ICs), three-dimensional integrated circuit (3DIC) stacks, network switches, sensors, baseboard management controllers (BMCs), electrical cables, network cables, passthroughs, or the like.

[0044] In an embodiment, heat distribution means 110 may include a remote heat sink or remote boiler disposed on a first end of heat distribution means 110. A remote heat sink or remote boiler may include a solid or hollow structure made, for example, of copper. A remote heat sink may have one or more chambers and be fluidically coupled with one or more heat pipes, the heat pipes functioning as heat distribution means 110 or disposed on heat distribution means 110. Further examples of remote heat sinks that may be used with heat transfer apparatuses in accordance with the present technology are described in U.S. Provisional Patent Applications 63 / 583,557, filed September 18, 2023 and entitled “Remote Boiler,” and 63 / 612,059, filed December 19, 2023 and entitled “Systems and Methods for Distributed Heat Transfer,” both of which are incorporated herein by reference in their entirety.

[0045] FIG. 2 illustrates a front view of heat transfer apparatus 100 including heat distribution means 110, floating ride-on plate 120, TIM 130, attachment means 140, backing plate 142, securing mechanism 144, and protrusions 146. FIG. 2 additionally illustrates a front view of component 170 and PCB 180. FIG. 2 shows securing mechanism 144 interfaced with protrusions 146. Securing mechanism 144 is mechanically attached to backing plate 142 and exerts a downward force on heat distribution means 110, which inturn exerts a downward force on floating ride-on plate 120 through TIM 130 and keeps floating ride-on plate 120 in contact with component 170.

[0046] FIG. 3 depicts aspects of an immersion cooling system 300 for dissipating heat from one or more heat-generating components such as semiconductor die packages 305 via immersion cooling. Each package 305 can include one or more semiconductor dies that produce heat when the system is in operation. The immersion cooling system 300 in the illustrated example of FIG. 3 is a two-phase immersion cooling system, though the invention may also be implemented in a single-phase immersion cooling system. The present technology may provide a mechanism to transfer excess waste heat from one or more components located outside of the immersion cooling liquid 364 into the immersion cooling liquid 364 and take advantage of the beneficial heat transfer properties of immersion cooling fluid.

[0047] Immersion cooling systems may provide particular advantage to 3DIC stacks due to the lower surface area to volume ratio of a 3DIC stack compared to the individual components of the 3DIC stack (e.g., a bonded logic IC and memory module will have a lower surface area to volume ratio than the combined logic IC and memory module when physically separated) as well as the additional heat generated by state of the art logic ICs. This lower surface area to volume ratio means waste heat generated by the 3DIC stack may not be as efficiently dissipated and may require better cooling performance than air cooling can provide. Two-phase immersion cooling in particular can provide this additional heat removal required by 3DIC stacks.

[0048] Immersion cooling system 300 includes a container such as tank 320 filled, at least in part, with immersion cooling liquid 364. The immersion cooling system 300 can further include at least one chiller 380 that flows a heat-transfer fluid through at least one condenser coil 370 that is disposed in the tank 320 and headspace 308. Condenser coil 370 and chiller 380 may be part of a heat exchanger. The packages 305 can be mounted on one or more printed circuit boards (PCBs) 357 that are immersed, at least in part, in the immersion cooling liquid 364. Immersion-cooling system 300 may further include a filter 375 disposed adjacent to the tank 320.

[0049] Filter 375 may include a filtration media, a housing, and a pump configured to force immersion cooling liquid 364 through filter 375 to remove contaminants, particulates, or other impurities that may be added to immersion cooling liquid 364 duringuse. Filter 375 may be housed outside of tank 320 while being in fluidic communication with immersion cooling liquid 364 in tank 320. Alternatively, filter 375 may be submerged within immersion cooling liquid 364 inside of tank 320.

[0050] Immersion cooling liquid 364 may be a hydrocarbon, a fluoroketone, an oil, or a similar dielectric liquid that will act as an insulator while simultaneously transferring heat from package 305 more efficiently than air. An example of immersion cooling liquid 364 is Novec™ 649 produced by 3M™. An exemplary immersion cooling liquid 364 used in accordance with embodiments of the present invention may have a dielectric constant baseline value of about 1.8-2 at a frequency of about 1 kHz.

[0051] In an embodiment of the invention, immersion cooling liquid 364 may be considered unacceptably contaminated if the dielectric constant and / or dielectric loss tangent of immersion cooling fluid being used in an immersion cooling system 300 differs by a threshold amount as compared to unused or pure immersion cooling liquid 364. For example, immersion cooling liquid 364 may be considered unacceptably contaminated or degraded if the dielectric constant and / or dielectric loss tangent differs by a threshold of 10% or more as compared to unused or pure immersion cooling liquid 364. In an embodiment, a dielectric constant and / or dielectric loss tangent variation threshold may be 20%, 15%, 5%, 3%, 1%, or any suitable threshold.

[0052] Contamination of the immersion cooling liquid 364 and resulting changes to dielectric constant and / or dielectric loss tangent may alter or negatively impact operation of components within immersion cooling liquid 364 including semiconductor die(s) 350. An altered dielectric constant and / or dielectric loss tangent may result in undesirable cross-talk between components on a PCB, additional noise or reduction in signal strength transmitted along exposed wires of a PCB or semiconductor die(s) 350 submerged in immersion fluid, and / or signal dissipation through the immersion cooling liquid 364. Signal loss may be severe enough that two elements may be effectively represented as being separated by an open circuit despite being physically connected. In an embodiment, a dielectric constant and / or dielectric loss tangent variation threshold may be selected based on an observed or inferred effect on one or more submerged semiconductor die(s) 350. For example, an increase in PCIe bit error rate above an error rate baseline may be correlated with an increase in dielectric constant and / or dielectric loss tangent above a dielectric constant and / or dielectric loss tangent baseline. Accordingly, operation ofsemiconductor die(s) 350 may be throttled or suspended when a dielectric constant and / or dielectric loss tangent of immersion cooling liquid 364 exceeds a predetermined threshold.

[0053] Changes to dielectric constant and / or dielectric loss tangent may be caused by contaminants within immersion cooling liquid 364. In some cases, changes to dielectric constant and / or dielectric loss tangent may be reversed by filtering the contaminants from immersion cooling liquid 364. In some embodiments, upon detecting an increase in dielectric constant and / or dielectric loss tangent of immersion cooling liquid 364, controller 302 may instruct filter 375 to increase filtration throughput or notify a user that an immersion cooling liquid 364 filtration media may need to be replaced. If a dielectric constant and / or dielectric loss tangent exceeds a predetermined threshold, controller 302 may throttle or shut down one or more semiconductor die(s) 350, generate a notification that immersion cooling liquid 364 should be replaced, trigger an alarm, etc.

[0054] The illustrated example of FIG. 3 is not intended to be to scale. The immersion cooling system 300 may house and provide immersion cooling liquid 364 to tens, hundreds, or even thousands of packages 305. In some cases, the immersion cooling system 300 can be small (e.g., the size of a floor unit air conditioner, approximately 1 meter high, 0.5 meter width, 0.5 meter depth or length). In some implementations, the immersion cooling system can be large (e.g., the size of a van or larger, approximately 2.5 meters high, 2.5 meters width, 4 meters depth or length).

[0055] The immersion cooling system 300 can also include a controller 302 (e.g., a microcontroller, programmable logic controller (PLC), microprocessor, field- programmable gate array, logic circuitry, memory, or some combination thereof) to manage system operation. Controller 302 can perform various system functions such as monitoring temperatures of system components, cooling fluid level, tank access, chiller operation etc. The controller 302 can further issue commands to control system operation such as executing a start-up sequence, executing a shut-down sequence, assigning workloads among the packages, changing cooling fluid level, changing the temperature of the heat-transfer fluid circulated by the chiller 380, etc. In some implementations, controller 302 can include (or itself be) a baseboard management controller (BMC) 304. That is, the BMC 304 may monitor and control all aspects of system operation for the immersion cooling system 300 in addition to monitoring and controlling workloads of the semiconductor dies 350 in the packages 305 cooled by the system. The immersion coolingsystem 300 can also include a network interface controller (NIC 303) to allow the system to communicate over a network, such as a local area network or wide area network. The immersion cooling system 300 can further include a fluid sensor array 390 having a plurality of fluid sensors 310. Fluid sensors 310 may include one or more leak detection sensors at least partially submerged in immersion cooling liquid 364.

[0056] The semiconductor die(s) 350 and can be mounted on and attached to a printed circuit board (PCB) 355 (sometimes referred to as a substrate) in device package 305. The package 305 can be made commercially available as an off-the-shelf (OTS) product. The package 305 can be used for single-phase or two-phase immersion cooling of at least one semiconductor die 350, such as a microprocessor (e.g., a central processing unit (CPU) and / or graphics processing unit (GPU)), voltage regulator (VR), high bandwidth memory (HBM), a digital signal processing (DSP) die, an artificial intelligence (Al) accelerator, an application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), and / or other densely patterned semiconductor die.

[0057] In the two-phase immersion cooling system 300 of FIG. 3, heat flows from the semiconductor die 350 where it is generated into the heat spreader 352. The heat spreader 352 is in thermal contact with an immersion cooling liquid 364 that can flow over and extract heat from the heat spreader 352. The amount of heat delivered by the heat spreader 352 to the immersion cooling liquid 364 is enough to boil the immersion cooling liquid 364 that contacts the heat spreader 352 (creating bubbles 365 and potentially creating froth 367 when bubbles 365 reach the surface of immersion cooling liquid 364). The vapor 366 from the boiled immersion cooling liquid 364 can be cooled and condensed back to liquid droplets 368, for example, by the condenser coil 370. The heat-transfer fluid, such as chilled water, from the chiller 380 can be circulated through the condenser coil 370 to lower the temperature of the condenser coil 370 below the condensation point in the headspace 308 of the tank 320. As a result, vapor 366 condenses on exterior surfaces of the condenser coil 370 and liquid droplets 368 from the condensed vapor can drip and / or flow back to the immersion cooling liquid 364. Although a single condenser coil 370 is depicted in FIG. 3, there can be a plurality of condenser coils 370 in tank 320 to condense the vapor 366 into droplets. Some or all of the condenser coils 370 may or may not be located directly over the PCBs 357. Instead, the condenser coil(s) 370 can be located near one or more walls of the tank 320, such that the condenser coil(s) 370 are not directly overthe PCBs 357 on which the packages 305 are mounted.

[0058] To improve thermal performance in two-phase immersion cooling system 300, the heat spreader 352 can include a boiling enhancement coating (BEC) on at least one surface. The BEC can be formed from copper or a copper alloy and can be porous, for example, though BECs can take various forms. In some cases, the BEC is a micro porous copper coating having a thickness from approximately or exactly 50 microns to 500 microns thick (which may be produced by electroplating and / or etching). In some implementations, the BEC comprises a mesh copper layer bonded (e.g., via resistance heating) to at least an outer surface of the heat spreader 352. In some cases, the BEC is applied as particulates to at least one smooth surface of the heat spreader 352 and then subsequently sintered to adhere to one another and to the heat spreader 352. The BEC provides an improved surface area to contact the immersion cooling liquid 364 and can increase the heat transfer coefficient from the heat spreader 352 to the immersion cooling liquid 364 by up to a factor of 15 versus a smooth surface on the heat spreader 352. Accordingly, BECs can increase thermal conductivity to, and accelerate the boiling of, the immersion cooling liquid 364.

[0059] Further implementations of boiling enhancement coatings and enclosures are possible. Additional arrangements, applications, and methods of use of boiling enhancement coatings and enclosures, including with semiconductor dies and 3DIC stacks, are described in the below U.S. Patent Applications.

[0060] U.S. Patent Application No. 18 / 327,615, filed June 1, 2023 and entitled "Boiler Enhancement Coatings with Active Boiling Management,” discloses heat spreader and boiling enhancement enclosure architectures thermally and / or mechanically coupled to one or more semiconductor dies or logic ICs that may be used for passive and / or active management of immersion cooling fluid boiling, including through the use of valves to control pressure of boiling immersion cooling fluid within a boiling enhancement chamber, particularly in paragraphs

[0018] -

[0039] and FIGS. 3-5B. The entirety of U.S. Patent Application No. 18 / 327,615 is incorporated herein by reference.

[0061] U.S. Provisional Patent Application No. 63 / 500,167, filed May 4, 2023, and entitled “Direct to Chip Heat Spreader and Boiler Enhancement Coatings for Microelectronics,” discloses heat spreader and BECs thermally and / or mechanically coupled to one or more semiconductor dies, logic ICs, and / or 3DIC stacks, particularly inparagraphs

[0015] -

[0033] and FIGS. 2A-4. BEC form factors may include graphite heat spreader architectures, vapor chambers, heat pipes, copper plates, fins, and the like. BEC form factors may be thermally and / or mechanically coupled to the one or more semiconductor dies, logic ICs, and / or 3DIC stacks through a thermally conductive epoxy, and may have varying dimensions relative to a surface to which the semiconductor dies and / or logic ICs are mounted. The entirety of U.S. Provisional Patent Application No. 63 / 500,167 is incorporated herein by reference.

[0062] U.S. Patent Application No. 18 / 460,091, filed September 1, 2023, and entitled “Direct to Chip Application of Boiling Enhancement Coating,” discloses BECs and methods for applying BECs to semiconductor dies, logic ICs, and / or 3DIC stacks in accordance with the present technology. In particular, paragraphs

[0024] -

[0046] and FIGS. 2A-5 disclose embodiments of BEC layers, adhesives, solders, sintering, laser ablation, meshes, and other BECs and BEC application methods. The entirety of U.S. Patent Application No. 18 / 460,091 is incorporated herein by reference.

[0063] U.S. Provisional Patent Application No. 63 / 506,945, filed June 8, 2023 and entitled “Vapor- Shedding Structures for Boiler Plates in Two-Phase Immersion Cooling Systems,” discloses structures that may be thermally and / or mechanically coupled to computing hardware such as one or more semiconductor dies, logic ICs, and / or 3DIC stacks to enable the shedding of immersion cooling vapors generated from the boiling of immersion cooling fluid during operation of the computing hardware. In particular, paragraphs

[0021] -

[0039] and FIGS. 3A-5 disclose vapor-shedding structures including varying porosities, constituent materials, and geometries relative to the computing hardware on which they are mounted. The entirety of U.S. Provisional Patent Application No. 63 / 506,945 is incorporated herein by reference.

[0064] U.S. Provisional Application No. 63 / 513,828, filed July 14, 2023 and entitled “Grinding Apparatuses and Methods for Mechanically Modifying Surfaces of Processors to Promote Boiling of a Coolant Liquid,” discloses methods for creating boiling enhancement modifications to surfaces such as the surfaces of computing hardware such as one or more semiconductor dies, logic ICs, and / or 3DIC stacks, particularly in paragraphs

[0036] -

[0095] and FIGS. 2A-8. For example, grooves, patterns, gouges, trenches, or other structures may be added to a surface or lid of a processor, semiconductor die, logic IC, 3DIC stack component, and / or BEC to encourage nucleation sites forbubbles of immersion cooling vapor to form during a cooling process, thus decreasing the thermal resistance between the processor, semiconductor die, logic IC, and / or 3DIC stack component and the surrounding immersion cooling fluid. The entirety of U.S. Provisional Application No. 63 / 513,828 is incorporated herein by reference.

[0065] U.S. Provisional Patent Application No. 63 / 513,829, filed July 14, 2023 and entitled “Electrical Connector Having a Heater to Facilitate Boiling of a Coolant Liquid to Improve Signal Integrity in Immersion Cooling Environment,” discloses heaters for promoting boiling of immersion cooling fluid near electrical connectors such as connections between components of a 3DIC stack and enable improved impedances at those connectors, particularly in paragraphs

[0019] -

[0052] and FIGS. 1A-3B. The entirety of U.S. Provisional Patent Application No. 63 / 513,829 is incorporated herein by reference.

[0066] U.S. Provisional Patent Application No. 63 / 603,242, filed November 28, 2023 and entitled “Woven Boiler Enhancement Coatings,” provides additional examples of BECs including woven BECs with variable weave patterns, densities, attachment mechanisms, and materials (including copper and tungsten) that may be attached to computing hardware such as one or more semiconductor dies, logic ICs, and / or 3DIC stacks in order to promote more efficient heat transfer and immersion cooling vapor nucleation, particularly in paragraphs

[0031] -

[0055] and FIGS. 3-7. The entirety of U.S. Provisional Patent Application No. 63 / 603,242 is incorporated herein by reference.Conclusion

[0067] While various inventive embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and / or structures for performing the function and / or obtaining the results and / or one or more of the advantages described herein, and each of such variations and / or modifications is deemed to be within the scope of the inventive embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and / or configurations will depend upon the specific application or applications for which the inventive teachings is / are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented byway of example only and that, within the scope of the appended claims and equivalents thereto, inventive embodiments may be practiced otherwise than as specifically described and claimed. Inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and / or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and / or methods, if such features, systems, articles, materials, kits, and / or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure.

[0068] Also, various inventive concepts may be embodied as one or more methods, of which an example has been provided. The acts performed as part of the method may be ordered in any suitable way. Accordingly, embodiments may be constructed in which acts are performed in an order different than illustrated, which may include performing some acts simultaneously, even though shown as sequential acts in illustrative embodiments.

[0069] All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms.

[0070] The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.”

[0071] The phrase “and / or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with “and / or” should be construed in the same fashion, i.e., “one or more” of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the “and / or” clause, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, a reference to “A and / or B”, when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to A only (optionally including elements other than B); in another embodiment, to B only (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.

[0072] As used herein in the specification and in the claims, “or” should be understood to have the same meaning as “and / or” as defined above. For example, when separating itemsin a list, “or” or “and / or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as “only one of’ or “exactly one of,” or, when used in the claims, “consisting of,” will refer to the inclusion of exactly one element of a number or list of elements. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives (i.e., “one or the other but not both”) when preceded by terms of exclusivity, such as “either,” “one of,” “only one of,” or “exactly one of.” “Consisting essentially of,” when used in the claims, shall have its ordinary meaning as used in the field of patent law.

[0073] As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified. Thus, as a nonlimiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and / or B”) can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc.

[0074] In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “composed of,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of’ and “consisting essentially of’ shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03.

Claims

CLAIMS1. An apparatus for transferring heat, the apparatus comprising: a heat distribution means configured to distribute heat from a component to a cooling medium; a thermal interface material disposed in thermal contact with at least one surface of the heat distribution means and at least one surface of a floating ride-on plate, wherein the floating ride-on plate is in thermal contact with the component; and an attachment means configured to secure a position of the heat distribution means relative to the component.

2. The apparatus of claim 1, wherein the attachment means is not in physical contact with the heat distribution means.

3. The apparatus of claim 2, further comprising a backing plate disposed in physical contact with the heat distribution means and attachment means; wherein the backing plate is configured to transfer a force from the attachment means to the heat distribution means.

4. The apparatus of claim 1, wherein the heat distribution means comprises one or more of a heat pipe, a liquid loop, or a solid block.

5. The apparatus of claim 4, wherein the solid block comprises copper, aluminum, or silver.

6. The apparatus of claim 1, wherein the floating ride-on plate comprises copper, aluminum, or silver.

7. The apparatus of claim 1, wherein the component comprises a small form-factor pluggable (SFP) connector.

8. The apparatus of claim 7, wherein the SFP connector comprises a quad small formfactor pluggable (QSFP) connector or an octal small form-factor pluggable (OSFP)connector.

9. The apparatus of claim 1, wherein the apparatus is disposed inside of an immersion cooling container, and a first end of the heat distribution means is immersed in a cooling medium.

10. The apparatus of claim 1, wherein the attachment means secures the position of the heat distribution means relative to the component by exerting a first force on the heat distribution means and a second force on the component; and wherein the second force is substantially equal and opposite to the first force.

11. The apparatus of claim 1, wherein the attachment means comprises at least one of a clip, a screw, a band, a magnet, a bracket, or a bolt.

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