Coolant-liquid reservoir in an immersion-cooling tank with stabilization system

Abstract

A coolant-liquid reservoir fluidically couples to the tank of an immersion-cooling system that is used to dissipate heat from semiconductor die packages. The coolant-liquid reservoir can be used to provide automated control of gas pressure in a headspace of the tank and / or coolant-liquid level in the tank of the immersion-cooling system. Systems for providing treatment of immersion cooling fluid are also disclosed. In an aspect, a reservoir of neutralizing agent is fluidically coupled to one or more reservoirs of immersion cooling fluid. A dispensing means fluidically couples the reservoir of neutralizing agent to the one or more reservoirs of immersion cooling fluid and controls a dispensing of neutralizing agent. A controller may operate the dispensing means in response to signals received by one or more sensors and cause neutralizing agent to be dispensed into the one or more reservoirs of immersion cooling fluid.

Description

COOLANT-LIQUID RESERVOIR IN AN IMMERSION-COOLING TANK WITHSTABILIZATION SYSTEMCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of and priority to U.S. Provisional Application No. 63 / 519,971, filed August 16, 2023, and U.S. Provisional Application No. 63 / 581,094, filed September 7, 2023, which applications are hereby incorporated by reference in their entireties.BACKGROUND

[0002] Section 1: As feature sizes and transistor sizes have decreased for integrated circuits (ICs), the amount of heat generated by a single chip, such as a microprocessor, has increased. Chips that once were air cooled have evolved to chips needing more heat dissipation than can be provided by air alone. In some cases, immersion cooling of chips in a tank containing a coolant liquid is employed to maintain IC chips at appropriate operating temperatures.

[0003] One type of immersion cooling is two-phase immersion cooling, in which heat from a semiconductor die is high enough to boil the coolant liquid. The boiling creates a coolant-liquid vapor in the tank, which is condensed by cooled coils or pipes back to liquid form. Heat from the semiconductor dies during operation can then be sunk into the liquid-to-gas and gas-to-liquid phase transitions of the coolant liquid.

[0004] Section 2: As feature sizes and transistor sizes have decreased for integrated circuits (ICs) including chips and semiconductor dies, the amount of heat generated by a single chip, such as a microprocessor, has increased. Chips that once were air cooled have evolved to chips needing more heat dissipation than can be provided by air alone. In some cases, immersion cooling of chips in a tank containing a cooling fluid is employed to maintain IC chips at appropriate operating temperatures.

[0005] One type of immersion cooling is two-phase immersion cooling, in which heat from a semiconductor die boils the cooling fluid. The boiling creates a cooling-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 cooling fluid. This allows chips to be run at a faster rate and allows for more computationally intensive processes than were previously possible. However, reaction products formed from chemical reactions between the cooling fluid and water may damage ICs and tank components.BRIEF SUMMARY

[0006] Section 1: The present disclosure relates to a coolant-liquid reservoir to aid in controlling pressure and / or the level of coolant liquid in an immersion-cooling tank of an immersion-cooling system. The immersion-cooling system is used to cool semiconductor die packages, which may be mounted in assembled units such as servers. Coolant liquid can be moved by thermal or mechanical means between the immersion-cooling tank and the coolantliquid reservoir to control the pressure and / or the level of the coolant liquid in the immersioncooling tank.

[0007] Some implementations relate to coolant-liquid reservoirs for an immersioncooling system in which semiconductor die packages are immersed in a coolant liquid. Such coolant-liquid reservoirs can comprise: a reservoir tank to contain the coolant liquid; a port to fluidically couple the reservoir tank to an immersion-cooling tank of the immersion-cooling system so that the coolant liquid can flow between the reservoir tank and the immersion-cooling tank when the reservoir tank is fluidically coupled to the immersion-cooling tank; and a temperature-control element that is thermally coupled to the reservoir tank.

[0008] Some implementations relate to methods of controlling pressure in an immersioncooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank. Such methods can comprise acts of: detecting, with a system controller, a pressure above a threshold pressure in a first headspace of the immersioncooling tank; and cooling gas in a second headspace of a reservoir tank that is fluidically coupled to the immersion-cooling tank to reduce the pressure in the immersion-cooling tank, wherein cooling the gas reduces a volume of the gas in the reservoir tank and draws liquid from the immersion-cooling tank into the reservoir tank.

[0009] Some implementations relate to methods of controlling a fluid level in an immersion-cooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank. Such methods can comprise acts of: detecting, with a fluid-level sensor, a fluid level of first coolant liquid in the immersion-cooling tank below a threshold fluid level; determining, with a system controller, that a pressure of a first gas in a first headspace of the immersion-cooling tank is below the threshold pressure; and increasing the fluid level in the immersion-cooling tank by heating, with a temperature-control element that is thermally coupled to a reservoir tank, a second gas in a second headspace of the reservoir tank to force a portion of second coolant liquid from the reservoir tank into theimmersion-cooling tank, wherein the reservoir tank is fluidically coupled to the immersioncooling tank by at least one conduit to transport the portion of coolant liquid.

[0010] Some implementations relate to coolant-liquid reservoirs for an immersioncooling system in which semiconductor die packages are immersed in a coolant liquid. Such coolant-liquid reservoirs can comprise: a reservoir tank to contain the coolant liquid; a port to fluidically couple the reservoir tank to an immersion-cooling tank of the immersion-cooling system so that the coolant liquid can flow between the reservoir tank and the immersion-cooling tank when the reservoir tank is fluidically coupled to the immersion-cooling tank; and a pump that is fluidically coupled to the port.

[0011] Some implementations relate to methods of controlling pressure in an immersioncooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank. Such methods can comprise acts of: detecting, with a system controller, a pressure above a threshold pressure in a first headspace of the immersioncooling tank; and pumping, with a pump that is communicatively coupled to and controlled by the system controller, coolant liquid from the immersion-cooling tank to a reservoir tank that is fluidically coupled to the immersion-cooling tank such that pressure in the headspace of the immersion-cooling tank reduces.

[0012] Some implementations relate to methods of controlling a fluid level in an immersion-cooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank. Such methods can comprise acts of: detecting, with a fluid-level sensor, a fluid level of first coolant liquid in the immersion-cooling tank below a threshold fluid level; determining that a pressure of a first gas in a first headspace of the immersion-cooling tank is below a threshold pressure; and increasing the fluid level in the immersion-cooling tank by pumping, with a pump that is fluidically coupled to a reservoir tank, a portion of second coolant liquid from the reservoir tank into the immersion-cooling tank.

[0013] 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 subject matter appearing in 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.

[0014] Section 2: Two-phase immersion cooling systems remove waste heat from computing hardware such as ICs, chips, and semiconductor dies by immersing the computinghardware in a dielectric immersion cooling fluid (often embodied as a liquid reservoir) that conducts heat better than air but acts as an insulator. When the computing hardware operates, the excess heat causes the immersion cooling fluid to boil, creating immersion cooling vapor. This vapor may then rise into the headspace of an immersion cooling tank, where it may contact condenser tubes and recondense into liquid form. The immersion cooling liquid then falls back into the liquid reservoir.

[0015] The headspace of an immersion cooling tank may contain condenser tubes from a heat exchanger used to cool immersion vapor and condense the immersion cooling vapor back into immersion cooling liquid. These condenser tubes may be filled with large volumes of water flowing at hundreds of gallons per minute. In the event of a leak or crack in these condenser tubes, significant quantities of water may be added to the immersion cooling fluid contained within the immersion cooling tank. The headspace of an immersion cooling tank may additionally contain water vapor from various sources including ambient humidity introduced when a tank lid is opened. Further, if a lid of an immersion cooling tank is open when a fire suppression system is open, water may be introduced to the tank inadvertently.

[0016] When this water comes into contact with immersion cooling vapor, it may react chemically and form reaction products such as acids (e.g., pentafluoropropionic acid (PFPA)) or other corrosive compounds. These reaction products may corrode or otherwise damage components of the immersion cooling system or immersed computing hardware, cause short circuits, reduce the insulative properties of the immersion cooling fluid, clog filters, or otherwise impede operation of the immersion cooling system.

[0017] The inventors have recognized and appreciated the need for systems for mitigating products of reactions between water and immersion cooling vapor. Accordingly, the present invention is directed toward systems for the delivery of a neutralizing agent to one or more containers of immersion cooling fluid, for example as part of an immersion cooling tank.

[0018] In some aspects, the techniques described herein relate to a system for immersion cooling, the system including a reservoir of neutralizing agent and at least one reservoir of immersion cooling fluid. The system further includes a dispensing means fluidically coupling the reservoir of neutralizing agent to the at least one reservoir of immersion cooling fluid. The dispensing means is configured to dispense at least a portion of the neutralizing agent into the at least one reservoir of immersion cooling fluid. An exemplary neutralizing agent may be a fluid, a powder, or a fluid and powder mixed while being dispensed.

[0019] In some aspects, the techniques described herein relate to a system for immersion cooling, the system including a first container containing a neutralizing agent and a plurality of cooling containers fluidically coupled to the first container. The plurality of cooling containers contain immersion cooling fluid. The system further includes at least one sensor disposed in each cooling container of the plurality of cooling containers and a dispensing means configured to dispense the neutralizing agent into at least one of the plurality of cooling containers in response to a signal from the at least one sensor.

[0020] In some aspects, the techniques described herein relate to a system for immersion cooling, the system including a first container containing a neutralizing agent and a second container fluidically coupled to the first container. The second container contains immersion cooling fluid. The system further includes a dispensing means configured to dispense at least a portion of the neutralizing agent into the second container.

[0021] 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 DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0022] 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 and / or structurally similar elements).

[0023] FIG. 1.1 depicts an example of a two-phase immersion-cooling system that can be used to cool semiconductor dies and in which a coolant-liquid reservoir can be used.

[0024] FIG. 1.2 depicts a coolant- liquid reservoir coupled to an immersion-cooling tank that can be used in an immersion-cooling system such as that depicted in FIG. 1.1.

[0025] FIG. 1.3 depicts further details of an implementation of a temperature-control element that can be thermally coupled to a coolant-liquid reservoir of FIG. 1.2 and that comprises a conduit carrying heat-transfer liquid.

[0026] FIG. 1.4 depicts an additional implementation of a coolant- liquid reservoir that uses a pump to transfer coolant liquid between an immersion-cooling tank and reservoir tank to control pressure and / or fluid level in the immersion-cooling tank of FIG. 1.2.

[0027] FIG. 2.1 depicts aspects of an immersion-cooling system for dissipating heat from one or more semiconductor die packages via immersion cooling.

[0028] FIG. 2.2 illustrates a source of neutralizing agent fluidically coupled to a plurality of immersion cooling containers.

[0029] FIG. 2.3 illustrates a container of neutralizing agent fluidically coupled to a plurality of immersion cooling containers.

[0030] FIG. 2.4 illustrates a container of neutralizing agent fluidically coupled to a single immersion cooling container.DETAILED DESCRIPTION

[0031] Section 1: 1,1 Overview of Immersion-Cooling System

[0032] FIG. 1.1 depicts aspects of an immersion-cooling system 1-160 for dissipating heat from one or more semiconductor die packages 1-105 containing semiconductor dies. The heat is dissipated from the packages 1-105 via immersion cooling. FIG. 1.1 depicts an instance of cooling while the semiconductor dies are operating and generating enough heat to boil coolant liquid 1-164 in the immersion-cooling tank 1-107 of the system. Each package 1-105 can include one or more semiconductor dies that produce heat when the semiconductor dies are in operation. The packages 1-105 can be included in an assembled unit 1-210 (e.g., in a server system) which is depicted in FIG. 1.2. The immersion-cooling system 1-160 in the illustrated example of FIG. 1.1 is a two-phase immersion-cooling system, though the invention can also be implemented for single-phase immersion-cooling systems.

[0033] The immersion-cooling system 1-160 includes an immersion-cooling tank 1-107 filled at least in part with coolant liquid 1-164. The immersion-cooling system 1-160 can further include at least one chiller 1-180 that flows a heat-transfer fluid through at least one condenser coil 1-170 or through conduits located in the headspace 1-109 of the tank 1-107. The condenser coil(s) 1-170 or conduits can condense coolant liquid vapor 1-166 into droplets 1-168 that return to the coolant liquid 1-164. The packages 1-105 can be mounted on one or more printed circuitboards (PCBs) 1-157 that are immersed, at least in part, in the coolant liquid 1-164. In some implementations, a foam or froth 1-167 can form in the tank 1-107 above the coolant liquid 1- 164 when the system is in operation. The froth 1-167 can be formed mostly from bubbles 1-165 that collect across the surface of the coolant liquid 1-164 when the coolant liquid boils due to heat generated by the packages 1-105.

[0034] The illustrated example of FIG. 1.1 is not intended to be to scale. The immersioncooling system 1-160 can house and provide coolant liquid 1-164 to tens, hundreds, or even thousands of packages 1-105. In some cases, the tank 1-107 of an immersion-cooling system 1- 160 can be small (e.g., the size of a floor unit air conditioner, approximately 1 meter high, 0.5 meter wide, 0.5 meter deep or long). In some implementations, the tank 1-107 of an immersioncooling system can be large (e.g., the size of an automotive van, approximately 2.5 meters high, 2.5 meters wide, 4 meters deep or long). In some cases, the tank 1-107 of an immersion-cooling system 1-160 can be larger than an automotive van.

[0035] The immersion-cooling system 1-160 can also include a controller 1-102 (e.g., a microcontroller, programmable logic controller, microprocessor, field-programmable gate array, logic circuitry, memory, or some combination thereof) to manage operation of at least the cooling aspects of the immersion-cooling system 1-160. The controller 1-102 can perform various system functions such as monitoring temperatures of system components (such as packages 1-105), monitoring coolant liquid fluid level and temperature, monitoring technician access to the interior of the tank, monitoring pressure in the headspace 1-109, monitoring chiller operation etc. The controller 1-102 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 1-105 and / or assembled units 1-210, changing coolant liquid fluid level, changing the temperature of the heat-transfer fluid circulated by the chiller 1-180, etc. In some implementations, the controller 1-102 can include (or itself be) a baseboard management controller (BMC) 1-104. That is, the BMC 1-104 may monitor and control all aspects of system operation for the immersion-cooling system 1-160 in addition to monitoring and controlling workloads of the semiconductor dies 1-150 in the packages 1-105 and / or workloads among the assembled units 1-210 cooled by the immersion-cooling system 1-160. The immersion-cooling system 1-160 can also include a network interface controller (NIC) 1-103 to allow the system and / or system components to communicate over a network, such as a local area network or wide area network.

[0036] 1.2, Monitoring and Controlling Coolant Liquid Level and Pressure

[0037] When the immersion-cooling system 1-160 is operated over time, gasket degradation and / or servicing of components in the tank during operation can lead to evaporative loss of coolant liquid 1-164 from the tank 1-107. Conventionally, the tank 1-107 would be filled to a desired level with coolant liquid 1-164 prior to operation. Periodically, the level of coolant liquid could be checked manually and replenished manually as needed.

[0038] It can be important to maintain the level of coolant liquid 1-164 in the tank 1-107 within a predetermined range. For example, it would not be desirable if the level of the coolant liquid 1-164 and / or level of the froth 1-167 rose above condenser coils 1-170 within the tank or dropped below semiconductor die packages 1-105 on the PCBs 1-157. In some implementations, there can be other semiconductor devices (such as high bandwidth memory (HBM), for example) in the tank 1-107 that do not need immersion cooling, are not immersed, and for which immersion would not be desired. There may also be feed-through connectors located above the level of the coolant liquid 1-164 for which immersion would not be desired. Such feed-through connectors may be configured to pass power and / or signals through a wall or walls of the tank 1-107.

[0039] In some cases, it can also be desirable to maintain pressure within the headspace 1-109 of the tank within a predetermined range of pressures (e.g., within 25% of the ambient pressure). For example, an increase in vapor pressure within the tank 1-107 can increase the boiling point of the coolant liquid 1-164, which can undesirably reduce cooling capability and increase package temperatures. If the pressure becomes too high, unwanted venting of coolant liquid vapor 1-166 into the ambient environment can occur through a pressure-release valve coupled to the immersion-cooling tank. Such venting of coolant liquid vapor 1-166 incurs a loss of coolant liquid 1-164, contaminates air in the ambient environment, and increases the cost of operating the immersion-cooling system 1-160.

[0040] The inventors have recognized and appreciated that automated control of the coolant liquid level and / or pressure in an immersion-cooling tank 1-107 can be beneficial to operation of an immersion cooling system 1-160. Automated control can reduce the incidences of coolant liquid loss and potentially avoid damage to components in the tank due to loss of the coolant liquid 1-164 causing over-temperature conditions of semiconductor die packages 1-105 during system operation.

[0041] FIG. 1.2 depicts an implementation of an immersion-cooling tank 1-207 that includes a coolant- liquid reservoir 1-209 to aid in pressure and / or fluid level control in the immersion-cooling tank 1-207. The tank design and arrangement of components can be used inthe immersion-cooling system 160 of FIG. 1.1 (instead of the tank 1-107) for immersion-cooling of assembled units 1-210. The assembled units can include PCBs 1-157 and semiconductor die packages 1-105 mounted on the PCBs. The assembled units 1-210 can be loaded into and unloaded from the tank 1-207 through an opening 1-220 that is covered and sealed by an access door 1-212 when the system is in operation. The assembled units 1-210 can be servers, dedicated processing units, data-mining units, high bandwidth memory units, or other types of processing and / or memory units, for example.

[0042] In some implementations, the immersion-cooling tank 1-207 can include compartments 1-205 that are not filled with coolant liquid 1-164. The compartments 1-205 can be outside the main volume of the tank that is filled with coolant liquid 1-164, for example. The compartments 1-205 can be used to house server components, for example, that need not be cooled by liquid (e.g., signal routing electronics and connectors). Condensing pipes 1-270 can be located above and to the side of the assembled units 1-210 so that the assembled units can be lowered into and removed from the tank 1-207 without contacting the condensing pipes 1-270. There can be many more condensing pipes than the number shown in FIG. 1.2.

[0043] There can be one or more sensors mounted in the immersion-cooling tank 1-207. For example, there can be at least one fluid-level sensor 1-228 to sense the level of the coolant liquid 1-164 within the tank 1-207. In some cases, the fluid-level sensor 1-228 can further sense the level of froth 1-167 in the tank 1-207. An example of a fluid- level sensor 1-228 is described in U.S. provisional patent application No. 63 / 512,575, titled “Fluid Sensor for Immersion- Cooling Systems,” filed July 7, 2023, which application is incorporated herein by reference in its entirety. In some implementations, the fluid-level sensor 1-228 can further detect temperature of at least the coolant liquid 1-164.

[0044] At least one pressure sensor 1-225 can also be included within the immersioncooling tank 1-207. The pressure sensor 1-225 can be located in a headspace 1-109 of the tank 1-207. A pressure sensor 1-225 in the tank can be configured to detect the pressure of the gaseous mixture in the tank’s headspace 1-109. In some implementations, a pressure sensor 1- 225 can be configured to detect a differential pressure between the tank’s headspace 1-109 and the ambient environment.

[0045] The pressure sensor(s) 1-225 and fluid-level sensor(s) 1-228 can be communicatively coupled to the system controller 1-102 through wired and / or wireless links. During system operation, the controller 1-102 can regularly receive information about pressure within the tank 1-207 from the pressure sensor(s) 1-225. For example, the pressure informationcan be received at regular time intervals (e.g., at least once per second to at least once every 10 seconds or longer). Similarly, the controller 1-102 can regularly receive information about the level of the coolant liquid 1-164 within the tank 1-207 from the fluid-level sensor(s) 1-228 (e.g., at least once per second to at least once every 10 seconds or longer). The controller 1-102 may further receive information about the level of the froth 1-167 within the tank 1-207 at such regular intervals.

[0046] The coolant-liquid reservoir 1-209 can be fluidically coupled to the immersioncooling tank 1-207. The coolant- liquid reservoir 1-209 can comprise a reservoir tank 1-201 to contain coolant liquid 1-164 and gas in a headspace 1-211 of the coolant-liquid reservoir 1-209. The volume of the reservoir tank 1-201 can be from 5% to 25% of the volume of the immersioncooling tank 1-207 and can be a sealed volume. The reservoir tank 1-201 can be formed from a metal, a polymer, a ceramic, a glass, or some combination of these materials. Preferably, the interior walls of the reservoir tank 1-201 do not react with nor are corroded by the coolant liquid 1-164.

[0047] The coolant-liquid reservoir 1-209 can fluidically connect to the immersioncooling tank 1-207 with a connecting conduit 1-213 located below the normal operating level of coolant liquid 1-164 in the immersion-cooling tank 1-207. The conduit 1-213 can connect to a port 1-202 on the reservoir tank 1-201. The connecting conduit 1-213 (such as a tube or pipe) can be filled with coolant liquid 1-164 isolating the headspace 1-211 in the coolant- liquid reservoir 1-209 from the headspace 1-109 in the immersion-cooling tank 1-207 during operation of the system. The reservoir tank 1-201 surrounding the headspace 1-211 can be a sealed container such that the headspace 1-211 does not fluidically communicate with the ambient environment. In some implementations, a valve 1-240 can be located along the connecting conduit 1-213 to fluidically isolate (when closed) and fluidically couple (when opened) the coolant-liquid reservoir 1-209 and immersion-cooling tank 1-207. When the immersion-cooling system 1-161 is in operation, the immersion-cooling tank 1-207 is also sealed from the ambient environment (e.g., the access door 1-212 is closed and sealed to the immersion-cooling tank 1- 207).

[0048] At least one temperature-control element 1-230 (for heating and / or cooling) can be thermally coupled to the coolant- liquid reservoir 1-209 and / or to the connecting conduit 1- 213. The temperature-control element 1-230 can further be communicatively coupled to and controlled by the system controller 1-102. The temperature-control element(s) 1-230 can be located outside the reservoir tank 1-201 (e.g., arranged to heat and / or cool walls of the reservoirtank 1-201). In some cases, at least one of the temperature-control element(s) 1-230 can be located inside the reservoir tank 1-201. When placed in heating mode by the system controller 1-102, the temperature-control element(s) 1-230 can cause heating of gas in the headspace 1-211 (and may increase evaporation of coolant liquid 1-164) to expand the gas in the headspace 1-211 of the coolant-liquid reservoir 1-209. This expansion can displace and force coolant-liquid from the reservoir tank 1-201 into the immersion-cooling tank 1-207, increasing the fluid level and / or increasing pressure in the headspace 1-109 of the immersion-cooling tank 1-207. When placed in cooling mode by the system controller 1-103, the temperature-control element(s) 1-230 can cause cooling of the gas in the headspace 1-211 (and may condense coolant-liquid vapor 1-166 in the headspace 1-211) to reduce volume of the gas in the headspace 1-211 of the reservoir tank 1-201. This reduction in volume can draw in coolant-liquid 1-164 from the immersion-cooling tank 1-207 into the reservoir tank 1-201, decreasing the fluid level and / or decreasing the pressure in the headspace 1-109 of the immersion-cooling tank 1-207.

[0049] The temperature-control element(s) 1-230 can comprise one or more thermoelectric coolers, one or more resistive heating elements, one or more conduits that carry a heat-transfer liquid, or some combination of these components. The temperature-control element(s) 1-230 can be controlled by the system controller 1-102 responsive to feedback signals received by the system controller 1-102 from the pressure sensor(s) 1-225 and fluid-level sensor(s) 1-228 to control pressure and / or fluid level in the immersion-cooling tank 1-207. For example, if the controller 1-102 detects an increase in pressure or overpressure above a threshold pressure value in the headspace 1-109 of the immersion-cooling tank 1-207, then the controller 1-102 can place the temperature-control element(s) 1-230 in cooling mode to remove coolant liquid 1-164 from the immersion-cooling tank 1-207 and decrease pressure in the headspace 1- 109 of the immersion-cooling tank 1-207.

[0050] FIG. 1.3 depicts one example of a temperature-control element 1-230 that is implemented with conduits that carry heat-transfer liquid. The illustrated temperature-control element 1-230 can include a controlled mixing valve 1-320 that can change a mixing ratio of cooled heat-transfer liquid fluidically coupled by a first tube 1-312 to a cold source and heated heat-transfer liquid fluidically coupled by a second tube 1-314 to a hot source. The mixing valve 1-320 can be communicatively coupled to and controlled by the system controller 1-102. For example, increasing the amount of heat-transfer liquid from the cold source can cool the gas in the headspace 1-211 of the reservoir tank 1-201 to reduce the volume of the gas in the headspace 1-211. The reduced volume can draw in coolant liquid 1-164 from the immersion-cooling tank1-207 and cause a decrease in pressure in the headspace 1-109 of the immersion-cooling tank 1- 207.

[0051] The cold source can be an output from the system’s chiller 1-180, in some implementations, though other cold sources can be used (e.g., a separate chiller or liquid cooled using one or more TECs). The hot source can be taken from a return line to the system chiller 1- 180, though other hot sources can be used (e.g., a source using resistive or microwave heating of liquid). The temperature-control element 1-230 can include at least one conduit 1-330 that passes through the reservoir tank 1-201 and / or is thermally coupled to the reservoir tank 1-201 (e.g., thermally coupled to the exterior of the reservoir tank’s walls). A return line 1-340 can return heat-transfer liquid to the cold and / or hot source(s).

[0052] 1,3. Additional Implementation

[0053] FIG. 1.4 depicts another implementation for controlling fluid level and / or pressure in the immersion-cooling tank 1-207. In this implementation, the coolant-liquid reservoir 1-209 is fluidically coupled to the immersion-cooling tank 1-207 (not shown in FIG. 1.4) with at least one fluid pump 1-410. According to some implementations, the fluid pump 1- 410 is reversible such that it can pump coolant liquid from the immersion-cooling tank 1-207 to the coolant- liquid reservoir 1-209 in a first mode of operation and can also pump coolant liquid from the coolant-liquid reservoir 1-209 to the immersion-cooling tank 1-207 in a second mode of operation. The pump 1-410 can be communicatively coupled to and controlled by the system controller 1-102. The pump’s mode of operation can be selected by the system controller 1-102 responsive to feedback signals received by the system controller 1-102 from the pressure sensor(s) 1-225 and fluid- level sensor(s) 1-228 to control pressure and / or fluid level in the immersion-cooling tank 1-207. A valve 1-240 (also controlled by the system controller 1-102) can be included in the connecting conduit 1-213. The valve 1-240 can be opened when the pump is turned on and closed when the pump 1-410 is turned off to prevent backflow of coolant liquid 1-164. According to some implementations, the coolant-liquid reservoir 1-209 can include an expandable portion 1-415 (such as a flexible polymer diaphragm sealed to the reservoir tank 1- 210) to allow for the influx of coolant liquid from the immersion-cooling tank 1-207 while maintaining a sealed chamber to prevent evaporative loss of coolant liquid. Other examples of an expandable portion 1-415 can be bellows or a pneumatic piston assembly fluidically coupled to the reservoir tank 1-201.

[0054] Although the implementation of FIG. 1.4 is illustrated and described with a single, reversible fluidic pump 1-410, the system can be implemented in other ways. Forexample, two single-direction pumps can be used with two conduits that fluidically couple the reservoir tank 1-201 and immersion-cooling tank 1-207 along separate flow lines. One of the pumps can be activated by the system controller 1-102 to pump coolant liquid from the reservoir tank 1-201 to the immersion-cooling tank 1-207 (e.g., to increase fluid level in the immersioncooling tank 1-207). The other pump can be activated by the system controller 1-102 to pump coolant liquid 1-164 from the immersion-cooling tank 1-207 to the reservoir tank 1-201 (e.g., to decrease gas pressure in the headspace 1-109 of the immersion-cooling tank 1-207). Check valves can be used in each line to prevent backflow after the pumps are turned off.Alternatively, one single-direction pump can be used with multi-way valves (controlled by the system controller 1-102) and additional tubing connections to direct flow from the immersioncooling tank 1-207 to the reservoir tank 1-201 in a first valve configuration and from the reservoir tank 1-201 to the immersion-cooling tank in a second valve configuration.

[0055] 1,4, Operation Examples

[0056] For the implementations of FIG. 1.2 and FIG. 1.3, when an overpressure or high fluid level condition is detected in the immersion-cooling tank 1-207 by the system controller 1- 102, the valve 1-240 can be opened and the temperature-control element 1-230 can be activated by the system controller 1-102 to cool gas in the headspace 1-211 of the reservoir tank 1-201 causing coolant liquid from the immersion-cooling tank 1-207 to be drawn into the reservoir tank 1-201. The valve 1-240 can be closed when a desired pressure and / or fluid level is reached in the immersion-cooling tank 1-207. When an underpressure and / or low fluid level is detected in the immersion-cooling tank 1-207 by the system controller 1-102, the valve 1-240 can be opened and the temperature-control element 1-230 can be activated by the system controller 1-102 to heat gas in the headspace 1-211 of the reservoir tank 1-201 causing coolant liquid from the reservoir tank 1-201 to flow into the immersion-cooling tank 1-207. When a low fluid level is detected, the system controller can first determine that the pressure in the headspace 1-109 of the immersion-cooling tank 1-207 is below an upper threshold pressure so that coolant liquid 1-164 can flow into the tank 1-207 without causing an overpressure event. The valve 1-240 can be closed when a desired pressure and / or fluid level is reached in the immersion-cooling tank 1-207.

[0057] For the implementation of FIG. 1.4, when an overpressure or high fluid level condition is detected in the immersion-cooling tank 1-207 by the system controller 1-102, the valve 1-240 can be opened and the pump 1-410 can be activated by the system controller 1-102 to pump coolant liquid from the immersion-cooling tank 1-207 to the reservoir tank 1-201. The diaphragm 1-415 can deflect and / or stretch to accept added volume of coolant liquid in thereservoir 1-209 and the valve can be closed when a desired pressure and / or fluid level is reached in the immersion-cooling tank 1-207. When an underpressure and / or low fluid level is detected in the immersion-cooling tank 1-207 by the system controller 1-102, the valve 1-240 can be opened and the pump 1-410 can be activated by the system controller 1-102 to pump coolant liquid from the reservoir tank 1-201 to the immersion-cooling tank 1-207. When a low fluid level is detected, the system controller can first determine that the pressure in the headspace 1- 109 of the immersion-cooling tank 1-207 is below an upper threshold pressure so that coolant liquid 1-164 can be pumped back into the tank 1-207 without causing an overpressure event. The valve 1-240 can be closed when a desired pressure and / or fluid level is reached in the immersion-cooling tank 1-207.

[0058] 1.5. Conclusion

[0059] 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 by way of example only and that inventive embodiments may be practiced otherwise than as specifically described. 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.

[0060] 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.

[0061] 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.

[0062] Unless stated otherwise, the terms “approximately” and “about” are used to mean within ± 20% of a target (e.g., dimension or orientation) in some embodiments, within ± 10% of a target in some embodiments, within ± 5% of a target in some embodiments, and yet within ± 2% of a target in some embodiments. The terms “approximately” and “about” can include the target. The term “essentially” is used to mean within ± 3% of a target.

[0063] The indefinite articles “a” and “an,” as used herein, unless clearly indicated to the contrary, should be understood to mean “at least one.”

[0064] The phrase “and / or,” as used herein, 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.

[0065] As used herein, “or” should be understood to have the same meaning as “and / or” as defined above. For example, when separating items in 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 “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,” shall have its ordinary meaning as used in the field of patent law.

[0066] As used herein, 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 everyelement 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 non-limiting 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.

[0067] 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.

[0068] Section 2: Thermal Transfer Fluid Emergency Stabilization System

[0069] FIG. 2.1 depicts aspects of an immersion-cooling system 2-100 for dissipating heat from one or more semiconductor die packages 2-105 via immersion cooling. Each package 2-105 can include one or more semiconductor dies that produce heat when the system is in operation. The immersion-cooling system 2-100 in the illustrated example of FIG. 2.1 is a two- phase immersion-cooling system, though the invention may also be implemented in a singlephase immersion-cooling system.

[0070] The immersion-cooling system 2-100 includes a container such as tank 2-120 filled, at least in part, with immersion cooling liquid 2-164. The immersion-cooling system 2- 100 can further include at least one chiller 2-180 that flows a heat-transfer fluid through at least one condenser coil 2-170 that is disposed in the tank 2-120 and headspace 2-108. Condenser coil 2-170 and chiller 2-180 may be part of a heat exchanger. The packages 2-105 can be mounted on one or more printed circuit boards (PCBs) 2-157 that are immersed, at least in part, in the immersion cooling liquid 2-164. Immersion-cooling system 2-100 may further include a filter 2- 175 disposed adjacent to the tank 2-120.

[0071] Filter 2-175 may include a filtration media, a housing, and a pump configured to force immersion cooling liquid 164 through filter 2-175 to remove contaminants, particulates, or other impurities that may be added to immersion cooling liquid 2-164 during use. Filter 2-175 may be housed outside of tank 2-120 while being in fluidic communication with immersion cooling liquid 2-164 in tank 2-120. Alternatively, filter 2-175 may be submerged within immersion cooling liquid 2-164 inside of tank 2-120.

[0072] Immersion cooling liquid 2-164 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 2-105 more efficiently than air. An example of immersion cooling liquid 2-164 is Novec™ 2-649 produced by 3M™. An exemplary immersion cooling liquid 2-164 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.

[0073] In an embodiment of the invention, immersion cooling liquid 2-164 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 2-100 differs by a threshold amount as compared to unused or pure immersion cooling liquid 2-164. For example, immersion cooling liquid 2-164 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 2-164. In an embodiment, a dielectric constant and / or dielectric loss tangent variation threshold may be 20%, 15%, 5%, 3%, 1%, or any suitable threshold.

[0074] Contamination of the immersion cooling liquid 2-164 and resulting changes to dielectric constant and / or dielectric loss tangent may alter or negatively impact operation of components within immersion cooling liquid 2-164 including semiconductor die(s) 2-150. 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) 2-150 submerged in immersion fluid, and / or signal dissipation through the immersion cooling liquid 2-164. 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) 2-150. 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 losstangent above a dielectric constant and / or dielectric loss tangent baseline. Accordingly, operation of semiconductor die(s) 2-150 may be throttled or suspended when a dielectric constant and / or dielectric loss tangent of immersion cooling liquid 2-164 exceeds a predetermined threshold.

[0075] Changes to dielectric constant and / or dielectric loss tangent may be caused by contaminants within immersion cooling liquid 2-164. In some cases, changes to dielectric constant and / or dielectric loss tangent may be reversed by filtering the contaminants from immersion cooling liquid 2-164. In some embodiments, upon detecting an increase in dielectric constant and / or dielectric loss tangent of immersion cooling liquid 2-164, controller 2-102 may instruct filter 2-175 to increase filtration throughput or notify a user that an immersion cooling liquid 2-164 filtration media may need to be replaced. If a dielectric constant and / or dielectric loss tangent exceeds a predetermined threshold, controller 2-102 may throttle or shut down one or more semiconductor die(s) 2-150, generate a notification that immersion cooling liquid 2-164 should be replaced, trigger an alarm, etc.

[0076] The illustrated example of FIG. 2.1 is not intended to be to scale. The immersioncooling system 2-100 may house and provide immersion cooling liquid 2-164 to tens, hundreds, or even thousands of packages 2-105. In some cases, the immersion-cooling system 2-100 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).

[0077] The immersion-cooling system 2-100 can also include a controller 2-102 (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 2-102 can perform various system functions such as monitoring temperatures of system components, cooling fluid level, tank access, chiller operation etc. The controller 2-102 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 2-180, etc. In some implementations, the controller 2-102 can include (or itself be) a baseboard management controller (BMC) 2-104. That is, the BMC 2-104 may monitor and control all aspects of system operation for the immersion-cooling system 2-100 in addition to monitoring and controlling workloads of the semiconductor dies 2-150 in the packages 2-105 cooled by the system. The immersion-cooling system 2-100 can also include a network interface controller (NIC) 2-103 toallow the system to communicate over a network, such as a local area network or wide area network. The immersion-cooling system 2-100 can further include a fluid sensor array 2-190 having a plurality of fluid sensors 2-110. Fluid sensors 2-110 may include one or more leak detection sensors at least partially submerged in immersion cooling liquid 2-164.

[0078] The semiconductor die(s) 2-150 and can be mounted on and attached to a printed circuit board (PCB) 2-155 (sometimes referred to as a substrate) in device package 2-105. The package 2-105 can be made commercially available as an off-the-shelf (OTS) product. The package 2-105 can be used for single-phase or two-phase immersion cooling of at least one semiconductor die 2-150, such as a microprocessor (e.g., a central processing unit (CPU) and / or graphic processing unit (GPU)), voltage regulator (VR), high bandwidth memory (HBM), a digital signal processing (DSP) die, an application-specific integrated circuit (ASIC), field- programmable gate array (FPGA), and / or other densely patterned semiconductor die.

[0079] In the two-phase immersion-cooling system 2-100 of FIG. 2.1, heat flows from the semiconductor die 2-150 where it is generated into the heat spreader 2-152. The heat spreader 2-152 is in thermal contact with an immersion cooling liquid 2-164 that can flow over and extract heat from the heat spreader 2-152. The amount of heat delivered by the heat spreader 2-152 to the immersion cooling liquid 2-164 is enough to boil the immersion cooling liquid 2- 164 that contacts the heat spreader 2-152 (creating bubbles 2-165 and potentially creating froth 2-167 when bubbles 2-165 reach the surface of immersion cooling liquid 2-164). The vapor 2- 166 from the boiled immersion cooling liquid 2-164 can be cooled and condensed back to liquid droplets 2-168, for example, by the condenser coil 2-170. The heat-transfer fluid, such as chilled water, from the chiller 2-180 can be circulated through the condenser coil 2-170 to lower the temperature of the condenser coil 2-170 below the condensation point in the headspace 2-108 of the tank 2-120. As a result, vapor 2-166 condenses on exterior surfaces of the condenser coil 2- 170 and liquid droplets 2-168 from the condensed vapor can drip and / or flow back to the immersion cooling liquid 2-164. Although a single condenser coil 2-170 is depicted in FIG. 2.1, there can be a plurality of condenser coils 2-170 in the tank 2-120 to condense the vapor 2-166 into droplets. Some or all of the condenser coils 2-170 may or may not be located directly over the PCBs 2-157. Instead, the condenser coil(s) 2-170 can be located near one or more walls of the tank 2-120, such that the condenser coil(s) 2-170 are not directly over the PCBs 2-157 on which the packages 2-105 are mounted.

[0080] To improve thermal performance in two-phase immersion-cooling system 2-100, the heat spreader 2-152 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 100 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 2-152. In some cases, the BEC is applied as particulates to at least one smooth surface of the heat spreader 2-152 and then subsequently sintered to adhere to one another and to the heat spreader 2-152. The BEC provides an improved surface area to contact the immersion cooling liquid 2-164 and can increase the heat transfer coefficient from the heat spreader 2-152 to the immersion cooling liquid 2-164 by up to a factor of 15 versus a smooth surface on the heat spreader 2-152. Accordingly, BECs can increase thermal conductivity to, and accelerate the boiling of, the immersion cooling liquid 2-164.

[0081] FIG. 2.2 illustrates a system 2-200 including a source of neutralizing agent, such as a reservoir of neutralizing agent 2-212 in a neutralizing agent container 2-210, which is fluidically coupled to a plurality of immersion cooling containers 2-220a-p. System 2-200 may be located in a data center or similar location designed for providing large scale and / or cloud computational services such as Al model training, Bitcoin mining, computational modeling, or the like. In an embodiment, immersion cooling containers 2-220a-p may include all immersion cooling containers within a data center. An exemplary neutralizing agent 2-212 may be a fluid, a powder, or a fluid and powder mixed while being dispensed.

[0082] Each immersion cooling container 2-220a-p may contain a reservoir of immersion cooling fluid and may be embodied by or analogous to immersion cooling system 2-100 illustrated in FIG. 2.1. Immersion cooling containers 2-220a-p may be individual immersion cooling tanks containing computing hardware immersed within reservoirs of immersion cooling fluid. System 2-200 may include dispensing means 2-230 to dispense at least a portion of the neutralizing agent into at least one reservoir of immersion cooling fluid contained by containers 2-220a-p. Dispensing means 2-230 may dispense neutralizing agent 2-212 at a predetermined flow rate, for example at a flow rate from about 0.001 gallons per minute (GPM) to about 50 gpm, more particularly from about 0.1 gpm to about 10 gpm, still more particularly about 1 gpm to about 8 gpm, or still more particularly about 0.1 gpm to about 3 gpm, or any value, range, or combination therein.

[0083] Dispensing means 2-230 may provide a fluidic coupling between neutralizing agent container 2-210 and each immersion cooling container 2-220a-p. In an embodiment,dispensing means 2-230 may include one or more tubes, pipes, hoses, conduits, or similar elements for conveying neutralizing agent 2-212 from neutralizing agent container 2-210 to one or more immersion cooling containers 2-220a-p.

[0084] Dispensing means 2-230 may additionally include one or more flow control mechanisms for starting, controlling, and stopping a flow of neutralizing agent 2-212 from neutralizing agent container 2-210 into any one or more of immersion cooling containers 2-220a- p. In an embodiment, dispensing means 2-230 may include one or more valves, gates, shutoffs, or similar mechanisms for starting, controlling, and stopping a flow of neutralizing agent 2-212 from neutralizing agent container 2-210. In an embodiment, dispensing means 2-230 may include one or more flow control mechanisms for each immersion cooling container to which neutralizing agent container 2-210 is connected. For example, dispensing means 2-230 may include one or more valves attached to each individual immersion cooling container 2-220a-p or disposed on a portion of dispensing means 2-230 adjacent to each individual immersion cooling container 2-220a-p, allowing for control of the dispensation of neutralizing agent 2-212 to individual immersion cooling containers. In an embodiment, exemplary flow control mechanisms may be operated both manually and electronically. For example, a flow control mechanism may include a computer-operated valve that can be opened and closed by controller 2-205 and may additionally include a handle, lever, or similar device allowing a human to manually open or close the valve.

[0085] System 2-200 may include controller 2-205 for controlling the dispensing of neutralizing agent 2-212. Controller 2-205 may be communicatively coupled to one or more elements of system 2-200 including neutralizing agent container 2-210, immersion cooling containers 2-220a-p, and dispensing means 2-230. In an embodiment, controller 2-205 may be an element of a centralized control center in a data center in which system 2-200 is located. Controller 2-205 may include software configured to control a plurality of elements within a data center including dispensing means 2-230 (and associated flow control mechanisms), neutralizing agent container 2-210, and immersion cooling containers 2-220a-p.

[0086] Controller 2-205 may control the dispensing of neutralizing agent 2-212 by controlling the operation of one or more components of neutralizing agent container 2-210, immersion cooling containers 2-220a-p, and / or dispensing means 2-230. For example, controller 2-205 may send a signal to open one or more valves within dispensing means 2-230 and dispense a portion of neutralizing agent 2-212 to one or more immersion cooling containers 2-220a-p. Once an appropriate volume of neutralizing agent 2-212 has been dispensed, controller 2-205may send a signal to close the one or more valves and halt the dispensing of neutralizing agent 2- 212.

[0087] Controller 2-205 may initiate a flow of neutralizing agent 2-212 into one or more immersion cooling containers 2-220a-p in response to receiving one or more signals from one or more sensors included in containers 2-220a-p indicating a threshold condition has occurred. For example, controller 2-205 may initiate a flow of neutralizing agent 2-212 into one or more immersion cooling containers 2-220a-p in response to receiving one or more signals from a humidity sensor located within any of immersion cooling containers 2-220a-p that a humidity inside a container is higher than a threshold. In an additional or alternative embodiment, immersion cooling containers 2-220a-p may include flow rate or pressure sensors at an inlet and an outlet of a heat exchanger disposed within each immersion cooling container. Controller 2- 205 may initiate a flow of neutralizing agent 2-212 into one or more immersion cooling containers 2-220a-p in response to receiving one or more signals indicating that a difference between a water flow rate into a heat exchanger and a water flow rate out of a heat exchanger is greater than zero, indicating a leak. Controller 2-205 may utilize one or more sensor readings to determine an amount of water that has been introduced to an immersion cooling container and dispense an appropriate amount of neutralizing agent 2-212 in response to the amount of water determined to have been introduced to the immersion cooling container.

[0088] In an embodiment, a volume of neutralizing agent 2-212 to add to one or more of immersion cooling containers 2-220a-p may be determined by controller 2-205 based on a volume of immersion cooling fluid in one or more immersion cooling containers 2-220a-p, by an estimated or measured amount of water added to one or more of immersion cooling containers 2- 220a-p, by a measured humidity within one or more of immersion cooling containers 2-220a-p, or the like.

[0089] Neutralizing agent container 2-210 and / or dispensing means 2-230 may include a pump for pressurizing and flowing neutralizing agent from a source such as neutralizing agent container 2-210 to one or more immersion cooling containers 2-220a-p.

[0090] FIG. 2.3 illustrates a system 2-300 including a source of neutralizing agent, such as a reservoir of neutralizing agent 2-312 in a neutralizing agent container 2-310, which is fluidically coupled to a plurality of immersion cooling containers 2-320a-f. System 2-300 may be located in a data center or similar location designed for providing large scale and / or cloud computational services such as Al model training, Bitcoin mining, computational modeling, or the like. System 2-300 may be one of several clusters of immersion cooling containers fluidicallycoupled to a single neutralizing agent container 2-310 within a data center. For example, a single data center may contain several systems 2-300. An exemplary neutralizing agent 2-312 may be a fluid, a powder, or a fluid and powder mixed while being dispensed.

[0091] Each immersion cooling container 2-320a-f may contain a reservoir of immersion cooling fluid and may be embodied by or analogous to immersion cooling system 2-100 illustrated in FIG. 2.1. Immersion cooling containers 2-320a-f may be individual immersion cooling tanks containing computing hardware immersed within reservoirs of immersion cooling fluid. System 2-300 may include dispensing means 2-330 to dispense at least a portion of the neutralizing agent into at least one reservoir of immersion cooling fluid contained by containers 2-320a-f.

[0092] Dispensing means 2-330 may provide a fluidic coupling between neutralizing agent container 2-310 and each immersion cooling container 2-320a-f. In an embodiment, dispensing means 2-330 may include one or more tubes, pipes, hoses, conduits, or similar elements for conveying neutralizing agent 2-312 from neutralizing agent container 2-310 to one or more immersion cooling containers 2-320a-f. Dispensing means 2-330 may dispense neutralizing agent 2-312 at a predetermined flow rate, for example at a flow rate from about 0.001 gallons per minute (GPM) to about 50 gpm, more particularly from about 0.1 gpm to about 10 gpm, still more particularly about 1 gpm to about 8 gpm, or still more particularly about 0.1 gpm to about 3 gpm, or any value, range, or combination therein.

[0093] Dispensing means 2-330 may additionally include one or more flow control mechanisms for starting, controlling, and stopping a flow of neutralizing agent 2-312 from neutralizing agent container 2-310 into any one or more of immersion cooling containers 2-320a- f. In an embodiment, dispensing means 2-330 may include one or more valves, gates, shutoffs, or similar mechanisms for starting, controlling, and stopping a flow of neutralizing agent 2-312 from neutralizing agent container 2-310. In an embodiment, dispensing means 2-330 may include one or more flow control mechanisms for each immersion cooling container to which neutralizing agent container 2-310 is connected. For example, dispensing means 2-330 may include one or more valves attached to each individual immersion cooling container 2-320a-f or disposed on a portion of dispensing means 2-330 adjacent to each individual immersion cooling container 2-320a-f, allowing for control of the dispensation of neutralizing agent 2-312 to individual immersion cooling containers. In an embodiment, exemplary flow control mechanisms may be operated both manually and electronically. For example, a flow control mechanism may include a computer-operated valve that can be opened and closed by controller2-305 and may additionally include a handle, lever, or similar device allowing a human to manually open or close the valve.

[0094] System 2-300 may include controller 2-305 for controlling the dispensing of neutralizing agent 2-312. In an embodiment, controller 2-305 may be a data center floor controller or controller local to a group of immersion cooling containers such as 2-320a-f. Controller 2-305 may include a control plane communicatively coupled to system 2-300, a PLC, an FPGA, or other processor programmed to function as an appropriate controller. Controller 2- 305 may include software configured to control a plurality of elements within system 2-300 including dispensing means 2-330 (and associated flow control mechanisms), neutralizing agent container 2-310, and immersion cooling containers 2-320a-f.

[0095] Controller 2-305 may control the dispensing of neutralizing agent 2-312 by controlling the operation of one or more components of neutralizing agent container 2-310, immersion cooling containers 2-320a-f, and / or dispensing means 2-330. For example, controller 2-305 may send a signal to open one or more valves within dispensing means 2-330 and dispense a portion of neutralizing agent 2-312 to one or more immersion cooling containers 2-320a-f. Once an appropriate volume of neutralizing agent 2-312 has been dispensed, controller 2-305 may send a signal to close the one or more valves and halt the dispensing of neutralizing agent 2- 312.

[0096] Controller 2-305 may initiate a flow of neutralizing agent 2-312 into one or more immersion cooling containers 2-320a-f in response to receiving one or more signals from one or more sensors included in containers 2-320a-f indicating a threshold condition has occurred. For example, controller 2-305 may initiate a flow of neutralizing agent 2-312 into one or more immersion cooling containers 2-320a-f in response to receiving one or more signals from a humidity sensor located within any of immersion cooling containers 2-320a-f that a humidity inside a container is higher than a threshold. In an additional or alternative embodiment, immersion cooling containers 2-320a-f may include flow rate or pressure sensors at an inlet and an outlet of a heat exchanger disposed within each immersion cooling container. Controller 2- 305 may initiate a flow of neutralizing agent 2-312 into one or more immersion cooling containers 2-320a-f in response to receiving one or more signals indicating that a difference between a water flow rate into a heat exchanger and a water flow rate out of a heat exchanger is greater than zero, indicating a leak. Controller 2-305 may utilize one or more sensor readings to determine an amount of water that has been introduced to an immersion cooling container anddispense an appropriate amount of neutralizing agent 2-312 in response to the amount of water determined to have been introduced to the immersion cooling container.

[0097] In an embodiment, a volume of neutralizing agent 2-312 to add to one or more of immersion cooling containers 2-320a-f may be determined by controller 2-305 based on a volume of immersion cooling fluid in one or more immersion cooling containers 2-320a-f, by an estimated or measured amount of water added to one or more of immersion cooling containers 2- 320a-f, by a measured humidity within one or more of immersion cooling containers 2-320a-f, or the like.

[0098] Neutralizing agent container 2-310 and / or dispensing means 2-330 may include a pump for pressurizing and flowing neutralizing agent from a source such as neutralizing agent container 2-310 to one or more immersion cooling containers 2-320a-f.

[0099] FIG. 2.4 illustrates a system 2-400 including a source of neutralizing agent, such as a reservoir of neutralizing agent 2-412 in a neutralizing agent container 2-410, which is fluidically coupled to immersion cooling container 2-420. System 2-400 may be located in a data center or similar location designed for providing large scale and / or cloud computational services such as Al model training, Bitcoin mining, computational modeling, or the like. System 2-400 may be one of several similar systems within a data center. An exemplary neutralizing agent 2- 412 may be a fluid, a powder, or a fluid and powder mixed while being dispensed.

[0100] Immersion cooling container 2-420 may contain a reservoir of immersion cooling fluid and may be embodied by or analogous to immersion cooling system 2-100 illustrated in FIG. 2.1. Immersion cooling container 2-420 may be an individual immersion cooling tank containing computing hardware immersed within a reservoir of immersion cooling fluid. System 2-400 may include dispensing means 2-430 to dispense at least a portion of the neutralizing agent into at least one reservoir of immersion cooling fluid contained by containers 2-420a-f.

[0101] Dispensing means 2-430 may provide a fluidic coupling between neutralizing agent container 2-410 and each immersion cooling container 2-420a-f. In an embodiment, dispensing means 2-430 may include one or more tubes, pipes, hoses, conduits, or similar elements for conveying neutralizing agent 2-412 from neutralizing agent container 2-410 to one or more immersion cooling container 2-420. Dispensing means 2-430 may dispense neutralizing agent 2-412 at a predetermined flow rate, for example at a flow rate from about 0.001 gallons per minute (GPM) to about 50 gpm, more particularly from about 0.1 gpm to about 10 gpm, still more particularly about 1 gpm to about 8 gpm, or still more particularly about 0.1 gpm to about 3 gpm, or any value, range, or combination therein.

[0102] Dispensing means 2-430 may additionally include one or more flow control mechanisms for starting, controlling, and stopping a flow of neutralizing agent 2-412 from neutralizing agent container 2-410 into any one or more of immersion cooling container 2-420. In an embodiment, dispensing means 2-430 may include one or more valves, gates, shutoffs, or similar mechanisms for starting, controlling, and stopping a flow of neutralizing agent 2-412 from neutralizing agent container 2-410.

[0103] In an embodiment, dispensing means 2-430 may include one or more flow control mechanisms for each immersion cooling container to which neutralizing agent container 2-410 is connected. For example, dispensing means 2-430 may include one or more valves for controlling a flow of neutralizing agent 2-412 from neutralizing agent container 2-410 into immersion cooling container 2-420. In an embodiment, exemplary flow control mechanisms may be operated both manually and electronically. For example, a flow control mechanism may include a computer-operated valve that can be opened and closed by controller 2-405 and may additionally include a handle, lever, or similar device allowing a human to manually open or close the valve.

[0104] System 2-400 may include controller 2-405 for controlling the dispensing of neutralizing agent 2-412. In an embodiment, controller 2-405 may be a PLC disposed on immersion cooling container 2-420 and configured to monitor sensor readings from within immersion cooling container 2-420. Controller 2-405 may be further configured to transmit messages and / or sensor values to a higher-level controller such as controller 2-205 or controller 2-305.

[0105] Controller 2-405 may include software configured to control a plurality of elements within system 2-400 including dispensing means 2-430 (and associated flow control mechanisms), neutralizing agent container 2-410, and immersion cooling container 2-420. Controller 2-405 may control the dispensing of neutralizing agent 2-412 by the operation of one or more components of neutralizing agent container 2-410, immersion cooling container 2-420, and / or dispensing means 2-430. For example, controller 2-405 may send a signal to open one or more valves within dispensing means 2-430 and dispense a portion of neutralizing agent 2-412 to one or more immersion cooling container 2-420. Once an appropriate volume of neutralizing agent 2-412 has been dispensed, controller 2-405 may send a signal to close the one or more valves and halt the dispensing of neutralizing agent 2-412.

[0106] Controller 2-405 may initiate a flow of neutralizing agent 2-412 into immersion cooling container 2-420 in response to receiving one or more signals from one or more sensorsdisposed on or within immersion cooling container 2-420 indicating a threshold condition has occurred. For example, controller 2-405 may initiate a flow of neutralizing agent 2-412 into immersion cooling container 2-420 in response to receiving one or more signals from a humidity sensor located within immersion cooling container 2-420 that a humidity inside the container is higher than a threshold.

[0107] In an additional or alternative embodiment, immersion cooling container 2-420 may include flow rate or pressure sensors at an inlet and an outlet of a heat exchanger disposed within immersion cooling container 2-420. Controller 2-405 may initiate a flow of neutralizing agent 2-412 into immersion cooling container 2-420 in response to receiving one or more signals indicating that a difference between a water flow rate into a heat exchanger and a water flow rate out of the heat exchanger is greater than zero, indicating a leak. Controller 2-405 may utilize one or more sensor readings to determine an amount of water that has been introduced to an immersion cooling container and dispense an appropriate amount of neutralizing agent 2-412 in response to the amount of water determined to have been introduced to the immersion cooling container.

[0108] In an embodiment, a volume of neutralizing agent 2-412 to add to immersion cooling container 2-420 may be determined by controller 2-405 based on a volume of immersion cooling fluid in immersion cooling container 2-420, by an estimated or measured amount of water added to immersion cooling container 2-420, by a measured humidity within immersion cooling container 2-420, or the like.

[0109] Neutralizing agent container 2-410 and / or dispensing means 2-430 may include a pump for pressurizing and flowing neutralizing agent from neutralizing agent container 2-410 to immersion cooling container 2-420.

[0110] Conclusion

[0111] 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 nomore than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way 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.

[0112] 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.

[0113] 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.

[0114] 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.”

[0115] 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.

[0116] 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 items in a list, “or” or “and / or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, butalso 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.

[0117] 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 non-limiting 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.

[0118] 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.

[0119] A coolant-liquid reservoir for an immersion-cooling system in which semiconductor die packages are immersed in a first coolant liquid, the coolant- liquid reservoir can be summarized as including: a reservoir tank to contain a second coolant liquid; a port to fluidically coupled the reservoir tank to an immersion-cooling tank of the immersion-cooling system so that at least a portion of the first coolant liquid can flow between the reservoir tankand the immersion-cooling tank when the reservoir tank is fluidically coupled to the immersioncooling tank; and a temperature-control element that is thermally coupled to the reservoir tank.

[0120] The temperature-control element includes at least one thermoelectric cooler. The temperature-control element includes at least one conduit to carry heat-transfer liquid. The temperature-control element includes at least one resistive heating element. A volume of the reservoir tank is from 5% to 25% of the volume of the immersion-cooling tank. The reservoir tank includes a metal. The reservoir tank includes a polymer.

[0121] The coolant-liquid reservoir further includes a headspace in the reservoir tank to contain a first gas within a sealed volume of the reservoir tank above the second coolant liquid. The temperature-control element is arranged to heat the first gas within the sealed volume so as to force a portion of the second coolant liquid out of the reservoir tank through the port and to the immersion-cooling tank. The temperature-control element is arranged to cool the first gas within the sealed volume so as to draw at least the portion of the first coolant liquid into the reservoir tank through the port and from the immersion-cooling tank. The coolant-liquid reservoir further includes a connecting tube to fluidically couple the port to the immersioncooling tank; and a valve coupled to the connecting tube to fluidically isolate the reservoir tank from the immersion-cooling tank when the valve is closed.

[0122] The coolant-liquid reservoir in combination with the immersion-cooling tank further includes a pressuring sensor arranged to sense pressure of a second gas in a headspace of the immersion-cooling tank; and a fluid level sensor arranged to sense a level of the first coolant liquid in the immersion-cooling tank. The coolant-liquid reservoir in combination with immersion-cooling tank further includes a system controller communicatively coupled to the pressure sensor, the fluid-level sensor, and to the temperature-control element. The system controller is configured to detect an overpressure condition in the headspace of the immersioncooling tank; and responsive to detecting the overpressure condition, cool the first gas in the headspace of the reservoir tank to draw at least the portion of the first coolant liquid from the immersion-cooling tank into the reservoir tank.

[0123] A method of controlling in an immersion-cooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank can be summarized as including: detecting, with a system controller, a pressure above a threshold pressure for a first gas in a first headspace of the immersion-cooling tank; and reducing the pressure of the first gas in the first headspace of the immersion-cooling tank by cooling a second gas in a second headspace of a reservoir tank, wherein the reservoir tank is fluidically coupled tothe immersion-cooling tank, and cooling the second gas reduces a volume of the second gas in the reservoir tank and draws a first portion of first coolant liquid from the immersion-cooling tank into the reservoir tank.

[0124] Cooling the second gas includes activating, by the system controller, a temperature-control element that is thermally coupled to the reservoir tank. The temperaturecontrol element includes at least one thermoelectric cooler. The temperature-control element includes at least one conduit that carries heat-transfer liquid and that is thermally coupled to the reservoir tank. The system controller can be configured to receive an indication from a fluidlevel sensor that a fluid level in the immersion-cooling tank is below a threshold fluid level; and in response to receiving the indication, determine that the pressure of the first gas in the first headspace of the immersion-cooling tank is below the threshold pressure, and raise the fluid level in the immersion-cooling tank by heating, with the temperature-control element, the second gas in the second headspace of the reservoir tank to force a second portion of second coolant liquid from the reservoir tank into the immersion-cooling tank.

[0125] The method further includes detecting, with a fluid-level sensor, a fluid level in the immersion-cooling tank below a threshold fluid level; determining, with the system controller, that the pressure in the first headspace of the immersion-cooling tank is below the threshold pressure; and heating, with the temperature-control element, the second gas in the second headspace of the reservoir tank to force a second portion of second coolant liquid from the reservoir tank into the immersion-cooling tank.

[0126] A method of controlling fluid level in an immersion-cooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank can be summarized as including: detecting, with a fluid-level sensor, a fluid level of first coolant liquid in the immersion-cooling tank below a threshold fluid level; determining, with a system controller, that a pressure of a first gas in a first headspace of the immersion-cooling tank is below the threshold pressure; and increasing the fluid level in the immersion-cooling tank by heating, with a temperature-control element that is thermally coupled to a reservoir tank, a second gas in a second headspace of the reservoir tank to force a portion of second coolant liquid from the reservoir tank into the immersion-cooling tank, wherein the reservoir tank is fluidically coupled to the immersion-cooling tank by at least one conduit to transport the portion of coolant liquid.

[0127] A coolant-liquid reservoir for an immersion-cooling system in which semiconductor die packages are immersed in a first coolant liquid can be summarized asincluding: a reservoir tank to contain a second coolant liquid; a port to fluidically couple the reservoir tank to an immersion-cooling tank of the immersion-cooling system so that at least a portion of the first coolant liquid can flow between the reservoir tank and the immersion-cooling tank when the reservoir tank is fluidically coupled to the immersion-cooling tank; and a pump that is fluidically coupled to the port.

[0128] The pump is a reversible pump. A volume of the reservoir tank is from 5% to 25% of the volume of the immersion-cooling tank. The reservoir tank includes a metal. The reservoir tank includes a polymer. The coolant-liquid reservoir further includes a first headspace in the reservoir tank to contain a first gas within a sealed volume of the reservoir tank above the coolant liquid. The coolant-liquid reservoir further includes a flexible diaphragm sealed to the reservoir tank to allow for volume expansion of the reservoir tank due to inflow of at least the first portion of the first coolant liquid through the port from the immersion-cooling tank.

[0129] The coolant-liquid reservoir further includes a connecting tube to fluidically couple the pump and to the immersion-cooling tank; and a valve coupled to the connecting tube to fluidically isolate the reservoir tank from the immersion-cooling tank when the valve is closed. The coolant-liquid reservoir in combination with the immersion-cooling tank further includes a pressure sensor arranged to sense pressure of a second gas in a second headspace of the immersion-cooling tank; and a fluid-level sensor arranged to sense a level of the first coolant liquid in the immersion-cooling tank. The coolant-liquid reservoir in combination with the immersion-cooling tank further includes a system controller communicatively coupled to the pressure sensor, to the fluid-level sensor, and to the pump. The system controller is configured to detect an overpressure condition in the headspace of the immersion-cooling tank; and responsive to detecting the overpressure condition, activate the pump to pump at least the portion of the first coolant liquid from the immersion-cooling tank into the reservoir tank.

[0130] A method of controlling pressure of a gas in a first headspace of an immersioncooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank can be summarized as including: detecting, with a system controller, a pressure of the gas above a threshold pressure in the first headspace of the immersion-cooling tank; and reducing the pressure of the gas in the first headspace of the immersion-cooling tank by pumping, with a pump that is communicatively coupled to and controlled by the system controller, at least a first portion of first coolant liquid from the immersion-cooling tank to a reservoir tank that is fluidically coupled to the immersion-cooling tank.

[0131] The system controller is configured to receive an indication from a fluid-level sensor that a fluid level in the immersion-cooling tank is below a threshold fluid level; and in response to receiving the indication, determine that the pressure of the gas in the first headspace of the immersion-cooling tank is below the threshold pressure; and raise the fluid level in the immersion-cooling tank by pumping, with the pump, a second portion of second coolant liquid from the reservoir tank into the immersion-cooling tank.

[0132] The method further includes: detecting, with a fluid-level sensor, a fluid level in the immersion-cooling tank below a threshold fluid level; determining, by the system controller, that the pressure of the gas in the first headspace of the immersion-cooling tank is below the threshold pressure; and raising the fluid level in the immersion-cooling tank by pumping, with the pump, a second portion of second coolant liquid from the reservoir tank into the immersioncooling tank. The pump is a reversible pump.

[0133] A method of controlling fluid level in an immersion-cooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank can be summarized as including: detecting, with a fluid-level sensor, a fluid level of first coolant liquid in the immersion-cooling tank below a threshold fluid level; determining that pressure of a gas in a first headspace of the immersion-cooling tank is below a threshold pressure; and increasing the fluid level in the immersion-cooling tank by pumping, with a pump that is fluidically coupled to a reservoir tank, a portion of second coolant liquid from the reservoir tank into the immersion-cooling tank.

[0134] A system for immersion cooling can be summarized as including: a reservoir of a neutralizing agent; at least one reservoir of an immersion cooling fluid; and a dispensing means fluidically coupling the reservoir of the neutralizing agent to the at least one reservoir of the immersion cooling fluid; wherein the dispensing means is configured to dispense at least a portion of the neutralizing agent into the at least one reservoir of the immersion cooling fluid.

[0135] The at least one reservoir of the immersion cooling fluid includes a plurality of immersion cooling containers at least partially filled with the immersion cooling fluid. The system further includes a controller configured to control the dispensing means by dispensing the at least a portion of the neutralizing agent in response to a signal received from a sensor. The sensor includes at least one of a humidity sensor, a pressure sensor, or a flow rate sensor.

[0136] A system for immersion cooling can be summarized as including: a first container containing a neutralizing agent; a plurality of cooling containers fluidically coupled to the first container, the plurality of cooling containers containing an immersion cooling fluid; at least onesensor disposed in each cooling container of the plurality of cooling containers; and a dispensing means configured to dispense at least a portion of the neutralizing agent into at least one of the plurality of cooling containers in response to a signal from the at least one sensor. The at least one sensor includes at least one of a humidity sensor, a pressure sensor, or a flow rate sensor.

[0137] A system for immersion cooling can be summarized as including: a first container containing a neutralizing agent; a second container fluidically coupled to the first container, the second container containing immersion cooling fluid; and a dispensing means configured to dispense at least a portion of the neutralizing agent into the second container. The system further includes a controller communicatively coupled to the dispensing means, the controller configured to control the dispensing means by dispensing the at least a portion of the neutralizing agent into the second container in response to a signal received from a sensor. The sensor includes a humidity sensor, a pressure sensor, or a flow rate sensor. The dispensing means includes: a tube for conveying a neutralizing agent; and a valve for controlling a flow of the neutralizing agent, wherein the valve may be operated at least one of electronically or manually.

[0138] The various embodiments described above can be combined to provide further embodiments. All of the U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and / or listed in the Application Data Sheet are incorporated herein by reference, in their entirety. Aspects of the embodiments can be modified, if necessary to employ concepts of the various patents, applications and publications to provide yet further embodiments.

[0139] These and other changes can be made to the embodiments in light of the abovedetailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.

Claims

CLAIMS1. A coolant- liquid reservoir for an immersion-cooling system in which semiconductor die packages are immersed in a first coolant liquid, the coolant- liquid reservoir, comprising: a reservoir tank to contain a second coolant liquid; a port to fluidically couple the reservoir tank to an immersion-cooling tank of the immersion-cooling system so that at least a portion of the first coolant liquid can flow between the reservoir tank and the immersion-cooling tank when the reservoir tank is fluidically coupled to the immersion-cooling tank; and a temperature-control element that is thermally coupled to the reservoir tank.

2. The coolant-liquid reservoir of claim 1, wherein the temperature-control element comprises at least one thermoelectric cooler.

3. The coolant-liquid reservoir of claim 1, wherein the temperature-control element comprises at least one conduit to carry heat-transfer liquid.

4. The coolant-liquid reservoir of claim 1, wherein the temperature-control element comprises at least one resistive heating element.

5. The coolant-liquid reservoir of claims 1 through 4, wherein a volume of the reservoir tank is from 5% to 25% of the volume of the immersion-cooling tank.

6. The coolant-liquid reservoir of any one of claims 1 through 5, wherein the reservoir tank comprises a metal.

7. The coolant-liquid reservoir of any one of claims 1 through 5, wherein the reservoir tank comprises a polymer.

8. The coolant-liquid reservoir of any one of claims 1 through 7, further comprising a headspace in the reservoir tank to contain a first gas within a sealed volume of the reservoir tank above the second coolant liquid.

9. The coolant-liquid reservoir of claim 8, wherein the temperature-control element is arranged to heat the first gas within the sealed volume so as to force a portion of the second coolant liquid out of the reservoir tank through the port and to the immersion-cooling tank.

10. The coolant-liquid reservoir of claim 8, wherein the temperature-control element is arranged to cool the first gas within the sealed volume so as to draw at least the portion of the first coolant liquid into the reservoir tank through the port and from the immersion-cooling tank.

11. The coolant-liquid reservoir of any one of claims 1 through 10, further comprising: a connecting tube to fluidically couple the port to the immersion-cooling tank; and a valve coupled to the connecting tube to fluidically isolate the reservoir tank from the immersioncooling tank when the valve is closed.

12. The coolant-liquid reservoir of any one of claims 1 through 11, in combination with the immersion-cooling tank and further comprising: a pressuring sensor arranged to sense pressure of a second gas in a headspace of the immersion-cooling tank; and a fluid-level sensor arranged to sense a level of the first coolant liquid in the immersion-cooling tank.

13. The combination of claim 12, further comprising: a system controller communicatively coupled to the pressure sensor, the fluidlevel sensor, and to the temperature-control element.

14. The combination of claim 13, wherein the system controller is configured to: detect an overpressure condition in the headspace of the immersion-cooling tank; and responsive to detecting the overpressure condition, cool the first gas in the headspace of the reservoir tank to draw at least the portion of the first coolant liquid from the immersioncooling tank into the reservoir tank.

15. A method of controlling in an immersion-cooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank, the method comprising: detecting, with a system controller, a pressure above a threshold pressure for a first gas in a first headspace of the immersion-cooling tank; and reducing the pressure of the first gas in the first headspace of the immersion-cooling tank by cooling a second gas in a second headspace of a reservoir tank, wherein the reservoir tank is fluidically coupled to the immersion-cooling tank, and cooling the second gas reduces a volume of the second gas in the reservoir tank and draws a first portion of first coolant liquid from the immersion-cooling tank into the reservoir tank.

16. The method of claim 15, wherein cooling the second gas comprises activating, by the system controller, a temperature-control element that is thermally coupled to the reservoir tank.

17. The method of claim 16, wherein the temperature-control element comprises at least one thermoelectric cooler.

18. The method of claim 16, wherein the temperature-control element comprises at least one conduit that carries heat-transfer liquid and that is thermally coupled to the reservoir tank.

19. The method of any one of claims 16 through 18, wherein the system controller is configured to: receive an indication from a fluid-level sensor that a fluid level in the immersioncooling tank is below a threshold fluid level; and in response to receiving the indication, determine that the pressure of the first gas in the first headspace of the immersioncooling tank is below the threshold pressure, and raise the fluid level in the immersion-cooling tank by heating, with the temperature-control element, the second gas in the second headspace of the reservoir tank to force a second portion of second coolant liquid from the reservoir tank into the immersioncooling tank.

20. The method of any one of claims 16 through 18, further comprising: detecting, with a fluid-level sensor, a fluid level in the immersion-cooling tank below a threshold fluid level; determining, with the system controller, that the pressure in the first headspace of the immersion-cooling tank is below the threshold pressure; and heating, with the temperature-control element, the second gas in the second headspace of the reservoir tank to force a second portion of second coolant liquid from the reservoir tank into the immersion-cooling tank.

21. A method of controlling fluid level in an immersion-cooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank, the method comprising: detecting, with a fluid-level sensor, a fluid level of first coolant liquid in the immersioncooling tank below a threshold fluid level; determining, with a system controller, that a pressure of a first gas in a first headspace of the immersion-cooling tank is below the threshold pressure; and increasing the fluid level in the immersion-cooling tank by heating, with a temperaturecontrol element that is thermally coupled to a reservoir tank, a second gas in a second headspace of the reservoir tank to force a portion of second coolant liquid from the reservoir tank into the immersion-cooling tank, wherein the reservoir tank is fluidically coupled to the immersioncooling tank by at least one conduit to transport the portion of coolant liquid.

22. A coolant-liquid reservoir for an immersion-cooling system in which semiconductor die packages are immersed in a first coolant liquid, the coolant- liquid reservoir comprising: a reservoir tank to contain a second coolant liquid; a port to fluidically couple the reservoir tank to an immersion-cooling tank of the immersion-cooling system so that at least a portion of the first coolant liquid can flow between the reservoir tank and the immersion-cooling tank when the reservoir tank is fluidically coupled to the immersion-cooling tank; and a pump that is fluidically coupled to the port.

23. The coolant-liquid reservoir of claim 22, wherein the pump is a reversible pump.

24. The coolant-liquid reservoir of claim 22 or 23, wherein a volume of the reservoir tank is from 5% to 25% of the volume of the immersion-cooling tank.

25. The coolant-liquid reservoir of any one of claims 22 through 24, wherein the reservoir tank comprises a metal.

26. The coolant-liquid reservoir of any one of claims 22 through 24, wherein the reservoir tank comprises a polymer.

27. The coolant-liquid reservoir of any one of claims 22 through 26, further comprising a first headspace in the reservoir tank to contain a first gas within a sealed volume of the reservoir tank above the coolant liquid.

28. The coolant-liquid reservoir of any one of claims 22 through 27, further comprising a flexible diaphragm sealed to the reservoir tank to allow for volume expansion of the reservoir tank due to inflow of at least the first portion of the first coolant liquid through the port from the immersion-cooling tank.

29. The coolant-liquid reservoir of any one of claims 22 through 28, further comprising: a connecting tube to fluidically couple the pump and to the immersion-cooling tank; and a valve coupled to the connecting tube to fluidically isolate the reservoir tank from the immersion-cooling tank when the valve is closed.

30. The coolant-liquid reservoir of any one of claims 22 through 29, in combination with the immersion-cooling tank and further comprising: a pressure sensor arranged to sense pressure of a second gas in a second headspace of the immersion-cooling tank; and a fluid-level sensor arranged to sense a level of the first coolant liquid in the immersion-cooling tank.

31. The combination of claim 30, further comprising:a system controller communicatively coupled to the pressure sensor, to the fluidlevel sensor, and to the pump.

32. The combination of claim 31, wherein the system controller is configured to: detect an overpressure condition in the headspace of the immersion-cooling tank; and responsive to detecting the overpressure condition, activate the pump to pump at least the portion of the first coolant liquid from the immersion-cooling tank into the reservoir tank.

33. A method of controlling pressure of a gas in a first headspace of an immersioncooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank, the method comprising: detecting, with a system controller, a pressure of the gas above a threshold pressure in the first headspace of the immersion-cooling tank; and reducing the pressure of the gas in the first headspace of the immersion-cooling tank by pumping, with a pump that is communicatively coupled to and controlled by the system controller, at least a first portion of first coolant liquid from the immersion-cooling tank to a reservoir tank that is fluidically coupled to the immersion-cooling tank.

34. The method of claim 33, wherein the system controller is configured to: receive an indication from a fluid-level sensor that a fluid level in the immersioncooling tank is below a threshold fluid level; and in response to receiving the indication, determine that the pressure of the gas in the first headspace of the immersioncooling tank is below the threshold pressure; and raise the fluid level in the immersion-cooling tank by pumping, with the pump, a second portion of second coolant liquid from the reservoir tank into the immersion-cooling tank.

35. The method of claim 33, further comprising: detecting, with a fluid- level sensor, a fluid level in the immersion-cooling tank below a threshold fluid level; determining, by the system controller, that the pressure of the gas in the first headspace of the immersion-cooling tank is below the threshold pressure; andraising the fluid level in the immersion-cooling tank by pumping, with the pump, a second portion of second coolant liquid from the reservoir tank into the immersion-cooling tank.

36. The method of any one of claims 33 to 35, wherein the pump is a reversible pump.

37. A method of controlling fluid level in an immersion-cooling tank of an immersion-cooling system that is configured to cool semiconductor die packages in the immersion-cooling tank, the method comprising: detecting, with a fluid-level sensor, a fluid level of first coolant liquid in the immersioncooling tank below a threshold fluid level; determining that a pressure of a gas in a first headspace of the immersion-cooling tank is below a threshold pressure; and increasing the fluid level in the immersion-cooling tank by pumping, with a pump that is fluidically coupled to a reservoir tank, a portion of second coolant liquid from the reservoir tank into the immersion-cooling tank.

38. A system for immersion cooling, the system comprising: a reservoir of a neutralizing agent; at least one reservoir of an immersion cooling fluid; and a dispensing means fluidically coupling the reservoir of the neutralizing agent to the at least one reservoir of the immersion cooling fluid; wherein the dispensing means is configured to dispense at least a portion of the neutralizing agent into the at least one reservoir of the immersion cooling fluid.

39. The system of claim 38, wherein the at least one reservoir of the immersion cooling fluid comprises a plurality of immersion cooling containers at least partially filled with the immersion cooling fluid.

40. The system of claim 38, further comprising a controller configured to control the dispensing means by dispensing the at least a portion of the neutralizing agent in response to a signal received from a sensor.

41. The system of claim 40, wherein the sensor comprises at least one of a humidity sensor, a pressure sensor, or a flow rate sensor.

42. A system for immersion cooling, the system comprising: a first container containing a neutralizing agent; a plurality of cooling containers fluidically coupled to the first container, the plurality of cooling containers containing an immersion cooling fluid; at least one sensor disposed in each cooling container of the plurality of cooling containers; and a dispensing means configured to dispense at least a portion of the neutralizing agent into at least one of the plurality of cooling containers in response to a signal from the at least one sensor.

43. The system of claim 42, wherein the at least one sensor comprises at least one of a humidity sensor, a pressure sensor, or a flow rate sensor.

44. A system for immersion cooling, the system comprising: a first container containing a neutralizing agent; a second container fluidically coupled to the first container, the second container containing immersion cooling fluid; and a dispensing means configured to dispense at least a portion of the neutralizing agent into the second container.

45. The system of claim 44, further comprising a controller communicatively coupled to the dispensing means, the controller configured to: control the dispensing means by dispensing the at least a portion of the neutralizing agent into the second container in response to a signal received from a sensor.

46. The system of claim 45, wherein the sensor comprises a humidity sensor, a pressure sensor, or a flow rate sensor.

47. The system of any of claims 38-46, wherein the dispensing means comprises: a tube for conveying a neutralizing agent; anda valve for controlling a flow of the neutralizing agent, wherein the valve may be operated at least one of electronically or manually.

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