Patent Description:
The operation of electronic devices requires satisfactory thermal management to ensure proper function. As electronic devices become heated, the devices can suffer from device degradation, functional failure, and lower lifespan.

A heat sink can be used for removing heat from an electronic device to the ambient. The performance of a heat sink can be characterized by its thermal resistance, with a lower value representing a higher performance level. The thermal resistance generally includes the heat-spreading resistance within the heat sink and the convective resistance between the heat sink surface and the ambient environment. To minimize the heat-spreading resistance, materials with high thermal conductivity (e.g., copper and aluminum) are typically used to make the heat sink. However, this conductive heat transfer through solid materials is generally insufficient to meet the higher cooling requirements of modem electronic devices having large-scale electronic integration and high-performance processors. Thus, more efficient mechanisms have been developed and evaluated, and a vapor chamber has been one of those commonly considered mechanisms.

Vapor chambers make use of the heat pipe principle that combines the principles of thermal conductivity and phase transition to remove heat from an electronic device to the ambient. In a vapor chamber, a working fluid in contact with a first surface of the vapor chamber (e.g., a surface of the vapor chamber in contact with a heat source of the electronic device) turns into a vapor by absorbing heat from that surface. The vapor then travels within the vapor chamber to a second, cooler surface of the vapor chamber and condenses back into a liquid, thus releasing the latent heat. The working fluid then returns to the first surface of the vapor chamber (e.g., through capillary action, centrifugal force, or gravity) and the cycle repeats. Vapor chambers that make use of the heat pipe principle are disclosed in <CIT>, <CIT>, <CIT>, <CIT> and <CIT>. <CIT> discloses a vapor chamber according to the preamble of claim <NUM>.

Despite its advantage over heat sinks, existing vapor chambers may not be effective in dispersing heat from modern electronic devices having one or more high-performance processors that can operate in multiple modes. For example, due to space and form factor constraints, an electronic device may be provided with one vapor chamber. The single vapor chamber may be designed for dissipating heat either when the processor is operating in the steady state power mode or when the processor is operating in the turbo power mode, but may not be suited for both operational states of the processor. For example, when the single vapor chamber is designed for dissipating heat when the processor is operating in the steady state power mode, the amount of coolant in the vapor chamber may be optimized for such a purpose. However, a larger amount of coolant may be needed to dissipate the heat effectively when the processor is operating in the turbo power mode. Consequently, the single vapor chamber designed for dissipating heat when the processor is operating in the steady state power mode would be ineffective in dissipating heat when the processor is operating in the turbo power mode. As another example, when the single vapor chamber is designed for dissipating heat when the processor is operating in the turbo power mode, the amount of coolant in the vapor chamber may be optimised for such purpose. Furthermore, the thickness of such a vapor chamber may be greater. However, the increase in the thickness of such a vapor chamber and the volume of coolant in it can lead to an increase in the thermal resistance of such a vapor chamber. Consequently, the single vapor chamber designed for dissipating heat when the processor is operating in the turbo power mode would be ineffective in dissipating heat when the processor is operating in the steady state power mode.

Therefore, there exists a need for vapor chambers that eliminate or substantially reduce the tradeoff between efficient heat dissipation when the processor is operating in the turbo power mode and efficient heat dissipation when the processor is operating in the steady state power mode. Specifically, there exists a need for vapor chambers that can efficiently dissipate heat from a processor when the processor is operating in the steady state power mode and when the processor is operating in the turbo power mode.

According to a first aspect of the present disclosure, a vapor chamber is provided. The vapor chamber may include a sealed enclosure. The sealed enclosure may include: a main chamber; a first elongate chamber extending laterally from a first side of the main chamber; and a second elongate chamber extending laterally from a second, opposite side of the main chamber. The vapor chamber may further include a first capillary structure lining a first interior surface of the sealed enclosure, and a second capillary structure lining a second, opposite interior surface of the sealed enclosure. Distal portions of the first elongate chamber and the second elongate chamber may be configured as reservoirs that store an excess volume of a working fluid in a liquid state when a heat source is in a first operating state and release the excess volume of the working fluid towards the main chamber when the heat source is in a second operating state.

According to a second aspect of the present disclosure, a vapor chamber is provided. The vapor chamber may include a cover portion secured to a base portion to form a sealed enclosure. The sealed enclosure may include: a main chamber; a first elongate chamber extending laterally in a first direction from a first side of the main chamber; and a second elongate chamber extending laterally in a second, opposite direction from a second, opposite side of the main chamber. A width of the main chamber may be greater than a width of the first elongate chamber and a width of the second elongate chamber. The vapor chamber may further include: a first capillary structure disposed in the main chamber, the first elongate chamber, and the second elongate chamber, the first capillary structure lining a first interior surface of the sealed enclosure; and a second capillary structure disposed in the main chamber, the first elongate chamber, and the second elongate chamber, the second capillary structure lining a second, opposite interior surface of the sealed enclosure. Portions of the first capillary structure and the second capillary structure disposed in distal portions of the first elongate chamber and the second elongate chamber may be configured as reservoirs that modulate a volume of a working fluid circulating in the vapor chamber based on an operating state of a heat source.

According to a third aspect of the present disclosure a system is provided. The system may include a processor and a vapor chamber, where the processor is in physical contact with a surface of the vapor chamber. The vapor chamber may include a sealed enclosure including: a main chamber; a first elongate chamber extending laterally from a first side of the main chamber; and a second elongate chamber extending laterally from a second, opposite side of the main chamber. The vapor chamber may further include a first capillary structure lining a first interior surface of the sealed enclosure, and a second capillary structure lining a second, opposite interior surface of the sealed enclosure. Distal portions of the first elongate chamber and the second elongate chamber may be configured as reservoirs that modulate a volume of a working fluid circulating in the vapor chamber based on an operating state of the processor.

Implementations described below in the context of a device, apparatus, or system are analogously valid for the respective methods, and vice versa. Furthermore, it will be understood that the implementations described below may be combined, for example, a part of one implementation may be combined with a part of another implementation.

It should be understood that the terms "on", "over", "top", "bottom", "down", "side", "back", "left", "right", "front", "lateral", "side", "up", "down" etc., when used in the following description are used for convenience and to aid understanding of relative positions or directions, and not intended to limit the orientation of any device, or structure or any part of any device or structure. In addition, the singular terms "a", "an", and "the" include plural references unless context clearly indicates otherwise. Similarly, the word "or" is intended to include "and" unless the context clearly indicates otherwise.

In some aspects of what is described here, a vapor chamber may include a main, central chamber and elongate chambers that extend laterally in opposite directions from opposite sides of the main chamber. The vapor chamber may include capillary structures in the central and elongate chambers. Each of the elongate chambers may include a reservoir disposed at a distal portion of the respective elongate chamber (e.g., the portion of the elongate chamber farthest from the main, central chamber). In some aspects, the reservoirs may be located outside of a footprint of fin structures that are formed on a planar surface of the vapor chamber. The reservoirs may be configured to store an excess volume of working fluid (e.g., in the liquid state) that can be tapped when a processor is operating in a turbo power mode. Conversely, when the processor is operating in a steady state power mode, a nominal volume of working fluid may be used to dissipate heat from the processor, and the excess volume of the working fluid (e.g., in the liquid state) may be stored in the reservoirs when the processor is operating in the steady state power mode. These portions of the elongate chambers may be suitable as reservoirs since these portions may be the coolest portions of the vapor chamber, thus facilitating the storage of a liquid medium (e.g., working fluid in the liquid state) in the portions of the capillary structures disposed in the reservoirs. Provision of the reservoirs may allow the vapor chamber to modulate the volume of working fluid circulating in the vapor chamber (e.g., used in the evaporation-condensation cycles) based on the operating state of the processor.

In some instances, aspects of the systems and techniques described here provide technical improvements and advantages over existing approaches. For example, the proposed vapor chamber eliminates or substantially reduces the tradeoff between efficient heat dissipation when the processor is operating in the turbo power mode and efficient heat dissipation when the processor is operating in the steady state power mode. Specifically, the proposed vapor chamber can efficiently dissipate heat from a processor when the processor is operating in the steady state power mode and when the processor is operating in the turbo power mode. Furthermore, since the volume of working fluid used in the evaporation-condensation cycles is modulated based on the operating state of the processor, the proposed vapor chamber achieves low thermal resistance regardless of whether the processor is operating in the turbo power mode or in the steady state power mode. The proposed vapor chamber can also offer flexible design capabilities and can allow processors to be run at a high-performance state without compromising heat dissipation and device lifespan.

The following examples pertain to various aspects of the present disclosure.

Example <NUM> is a vapor chamber including: a sealed enclosure. The sealed enclosure includes: a main chamber; a first elongate chamber extending laterally from a first side of the main chamber; and a second elongate chamber extending laterally from a second, opposite side of the main chamber. The vapor chamber also includes a first capillary structure lining a first interior surface of the sealed enclosure, and a second capillary structure lining a second, opposite interior surface of the sealed enclosure. Distal portions of the first elongate chamber and the second elongate chamber are configured as reservoirs that store an excess volume of a working fluid in a liquid state when a heat source is in a first operating state and release the excess volume of the working fluid towards the main chamber when the heat source is in a second operating state.

In Example <NUM>, the subject matter of Example <NUM> may optionally include that the heat source includes a processor, and the first operating state is a steady state power mode of the processor, and the second operating state is a turbo power mode of the processor.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that portions of the first capillary structure and the second capillary structure disposed in the distal portions of the first elongate chamber and the second elongate chamber are configured as the reservoirs.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the excess volume of the working fluid is stored in and released from the portions of the first capillary structure and the second capillary structure disposed in the distal portions of the first elongate chamber and the second elongate chamber.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that each of the first capillary structure and the second capillary structure includes at least one of a sintered metal-containing powder, one or more layers of a metal-containing mesh, one or more layers of a metal-containing foam, or a metal-containing fiber structure.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the distal portions of the first elongate chamber and the second elongate chamber are disposed outside a footprint of a heat dissipation structure disposed on an exterior surface of the vapor chamber.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the heat dissipation structure includes a first fin structure disposed over a portion of the first elongate chamber, where the distal portion of the first elongate chamber is outside of the footprint of the first fin structure.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the heat dissipation structure includes a second fin structure disposed over a portion of the second elongate chamber, where the distal portion of the second elongate chamber is outside of the footprint of the second fin structure.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include a third capillary structure attached to the first capillary structure, where the third capillary structure is positioned between the first capillary structure and the second capillary structure.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that a distance between the first interior surface of the sealed enclosure and the second interior surface of the sealed enclosure in the main chamber is less than a distance between the first interior surface of the sealed enclosure and the second interior surface of the sealed enclosure in the reservoirs.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include a reservoir capillary structure disposed in each of the reservoirs, the reservoir capillary structure positioned between the third capillary structure and the second capillary structure.

Example <NUM> is a vapor chamber including: a cover portion secured to a base portion to form a sealed enclosure. The sealed enclosure includes: a main chamber; a first elongate chamber extending laterally in a first direction from a first side of the main chamber; and a second elongate chamber extending laterally in a second, opposite direction from a second, opposite side of the main chamber, where a width of the main chamber is greater than a width of the first elongate chamber and a width of the second elongate chamber. The vapor chamber also includes: a first capillary structure disposed in the main chamber, the first elongate chamber, and the second elongate chamber, the first capillary structure lining a first interior surface of the sealed enclosure; and a second capillary structure disposed in the main chamber, the first elongate chamber, and the second elongate chamber, the second capillary structure lining a second, opposite interior surface of the sealed enclosure. Portions of the first capillary structure and the second capillary structure disposed in distal portions of the first elongate chamber and the second elongate chamber are configured as reservoirs that modulate a volume of a working fluid circulating in the vapor chamber based on an operating state of a heat source.

In Example <NUM>, the subject matter of Example <NUM> may optionally include that the reservoirs are configured to: store an excess volume of the working fluid in a liquid state when the heat source is in a first operating state; and release the excess volume of the working fluid towards the main chamber when the heat source is in a second operating state.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that: in the first operating state of the heat source, a nominal volume of the working fluid is configured to circulate in the vapor chamber; and in the second operating state of the heat source, the nominal volume of the working fluid and the excess volume of the working fluid are configured to circulate in the vapor chamber.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the nominal volume of the working fluid is substantially equal to the excess volume of the working fluid.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the heat source includes a processor, and the first operating state is a steady state power mode of the processor, and the second operating state is a turbo power mode of the processor.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the heat dissipation structure includes a first fin structure formed on the cover portion and disposed over a portion of the first elongate chamber, where the distal portion of the first elongate chamber is outside of the footprint of the first fin structure.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the heat dissipation structure includes a second fin structure formed on the cover portion and disposed over a portion of the second elongate chamber, where the distal portion of the second elongate chamber is outside of the footprint of the second fin structure.

Example <NUM> is a system including: a processor and a vapor chamber, where the processor is in physical contact with a surface of the vapor chamber. The vapor chamber includes a sealed enclosure including: a main chamber; a first elongate chamber extending laterally from a first side of the main chamber; and a second elongate chamber extending laterally from a second, opposite side of the main chamber. The vapor chamber further includes a first capillary structure lining a first interior surface of the sealed enclosure, and a second capillary structure lining a second, opposite interior surface of the sealed enclosure. Portions of the first capillary structure and the second capillary structure disposed in distal portions of the first elongate chamber and the second elongate chamber are configured as reservoirs that modulate a volume of a working fluid circulating in the vapor chamber based on an operating state of the processor.

In Example <NUM>, the subject matter of Example <NUM> may optionally include that portions of the first capillary structure and the second capillary structure disposed in the distal portions of the first elongate chamber and the second elongate chamber are configured as the reservoirs.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include a circuit board, where the processor is attached to the circuit board and positioned between the circuit board and the vapor chamber.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that in a first operating state of the processor, a nominal volume of the working fluid is configured to circulate in the vapor chamber; and in a second operating state of the processor, the nominal volume and the excess volume of the working fluid are configured to circulate in the vapor chamber.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the reservoirs are configured to: store the excess volume of the working fluid in a liquid state when the processor is in the first operating state; and release the excess volume of the working fluid towards the main chamber when the processor is in the second operating state.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the first operating state is a steady state power mode of the processor, and the second operating state is a turbo power mode of the processor.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the vapor chamber further includes a third capillary structure attached to the first capillary structure, where the third capillary structure is positioned between the first capillary structure and the second capillary structure.

In Example <NUM>, the subject matter of any one of Examples <NUM> to <NUM> may optionally include that the vapor chamber further includes a reservoir capillary structure disposed in each of the reservoirs, the reservoir capillary structure positioned between the third capillary structure and the second capillary structure.

<FIG> is a block diagram showing an example electronic device <NUM>, according to an implementation of the present disclosure. The electronic device <NUM> may be a laptop computer, a desktop computer, a tablet computer, an automobile computer, a game console, a smart phone, a personal digital assistant, a server, or other electronic devices capable of running computer applications. In some implementations, the electronic device <NUM> includes a processor <NUM>, an input/output (I/O) module <NUM>, memory <NUM>, a power unit <NUM>, and one or more network interfaces <NUM>. The electronic device <NUM> can include additional components. In some implementations, the processor <NUM>, input/output (I/O) module <NUM>, memory <NUM>, power unit <NUM>, and the network interface(s) <NUM> are housed together in a common housing or other assembly.

The example processor <NUM> can execute instructions, for example, to generate output data based on data inputs. The instructions can include programs, codes, scripts, modules, or other types of data stored in memory (e.g., memory <NUM>). Additionally or alternatively, the instructions can be encoded as pre-programmed or re-programmable logic circuits, logic gates, or other types of hardware or firmware components or modules. The processor <NUM> may be, or may include, a multicore processor having a plurality of cores, and each such core may have an independent power domain and can be configured to enter and exit different operating or performance states based on workload. Additionally or alternatively, the processor <NUM> may be, or may include, a general-purpose microprocessor, as a specialized co-processor or another type of data processing apparatus. In some cases, the processor <NUM> performs high-level operation of the electronic device <NUM>. For example, the processor <NUM> may be configured to execute or interpret software, scripts, programs, functions, executables, or other instructions stored in the memory <NUM>.

The example I/O module <NUM> may include a mouse, keypad, touch screen, scanner, optical reader, and/or stylus (or other input device(s)) through which a user of the electronic device <NUM> may provide input to the electronic device <NUM>, and may also include one or more of a speaker for providing audio output and a video display device for providing textual, audiovisual, and/or graphical output.

The example memory <NUM> may include computer-readable storage media, for example, a volatile memory device, a non-volatile memory device, or both. The memory <NUM> may include one or more read-only memory devices, random-access memory devices, buffer memory devices, or a combination of these and other types of memory devices. In some instances, one or more components of the memory can be integrated or otherwise associated with another component of the electronic device <NUM>. The memory <NUM> may store instructions that are executable by the processor <NUM>. In some examples, the memory <NUM> may store instructions for an operating system <NUM> and for application programs <NUM>. The memory <NUM> may also store a database <NUM>.

The example power unit <NUM> provides power to the other components of the electronic device <NUM>. For example, the other components may operate based on electrical power provided by the power unit <NUM> through a voltage bus or other connection. In some implementations, the power unit <NUM> includes a battery or a battery system, for example, a rechargeable battery. In some implementations, the power unit <NUM> includes an adapter (e.g., an AC adapter) that receives an external power signal (from an external source) and coverts the external power signal to an internal power signal conditioned for a component of the electronic device <NUM>. The power unit <NUM> may include other components or operate in another manner.

The electronic device <NUM> may be configured to operate in a wireless, wired, or cloud network environment (or a combination thereof). In some implementations, the electronic device <NUM> can access the network using the network interface(s) <NUM>. The network interface(s) <NUM> can include one or more adapters, modems, connectors, sockets, terminals, ports, slots, and the like. The wireless network that the electronic device <NUM> accesses may operate, for example, according to a wireless network standard or another type of wireless communication protocol. For example, the wireless network may be configured to operate as a Wireless Local Area Network (WLAN), a Personal Area Network (PAN), a metropolitan area network (MAN), or another type of wireless network. Examples of WLANs include networks configured to operate according to one or more of the <NUM> family of standards developed by IEEE (e.g., Wi-Fi networks), and others. Examples of PANs include networks that operate according to short-range communication standards (e.g., BLUETOOTH®, Near Field Communication (NFC), ZigBee), millimeter wave communications, and others. The wired network that the electronic device <NUM> accesses may, for example, include Ethernet, SONET, circuit-switched networks (e.g., using components such as SS7, cable, and the like), and others.

In some implementations, the various components of the electronic device <NUM> may be disposed on one or more planar surfaces of a circuit board (e.g., a motherboard) that electrically and communicatively connects the various components of the electronic device <NUM> to one another. <FIG> is a schematic diagram showing a structure of an example circuit board <NUM>, according to an implementation of the present disclosure. The shape of the circuit board <NUM> shown in <FIG> is merely exemplary; the shape of the circuit board <NUM> may be different in other implementations. The circuit board <NUM> may be a motherboard of the electronic device <NUM> and may include a first (e.g., a top) surface <NUM> and a second (e.g., a bottom), opposing surface <NUM>. In some instances, the circuit board <NUM> may define a cutout <NUM> in a corner of the circuit board <NUM>. In the example of <FIG>, the circuit board <NUM> includes a first area <NUM>, a second area <NUM>, a third area <NUM>, and a fourth area <NUM>. The areas <NUM>, <NUM>, <NUM>, <NUM> shown in the <FIG> are merely exemplary, and the number of areas and their relative positions may be different in other implementations. The areas <NUM>, <NUM>, <NUM>, <NUM> may be configured to receive various components of the electronic device <NUM>, examples being the processor <NUM>, I/O module <NUM>, memory <NUM>, power unit <NUM>, and the network interface(s) <NUM> shown in <FIG>. In some instances, these components of the electronic device <NUM> may be mounted on the circuit board <NUM>, and the circuit board <NUM> may connect one or more hardware components of the electronic device <NUM> to the processor <NUM>, distribute power from the power unit <NUM>, or define the types of storage devices, memory modules, and graphics cards (among other expansion cards) that can connect to other components of the electronic device <NUM>.

The processor <NUM> may have multiple operating states, and may be configured to be in different operating states at different times. <FIG> is a diagram showing an example graph <NUM> illustrating processor power levels when a processor is in different operating states, according to an implementation of the present disclosure. The horizontal axis of graph <NUM> denotes time (in arbitrary units), and the vertical axis of the graph <NUM> denotes power (in arbitrary units). As seen in <FIG>, the processor <NUM> may initially be idle during an initial time period T<NUM>. During the initial time period T<NUM>, the processor <NUM> may be in a sleep or low power state and may build up a thermal budget. Following the initial time period T<NUM>, the processor <NUM> may enter a turbo power mode and be in the turbo power mode for a first operating time period T<NUM>. In some implementations, when in the turbo power mode, the processor <NUM> may operate above thermal design power (TDP) specifications. Specifically, after the initial time period T<NUM> (e.g., the processor idle period), the processor <NUM> has accumulated enough thermal budget to accommodate high power/performance for the first operating time period T<NUM>. In some instances, the first operating time period T<NUM> may be in a range from about <NUM> seconds to about <NUM> seconds, although other time durations are possible in other instances.

Following the first operating time period T<NUM>, the thermal budget previously accumulated by the processor <NUM> has been exhausted. Consequently, following the first operating time period T<NUM>, the processor <NUM> may stabilize to a normal operation mode or a steady state power mode. The turbo power mode differs from the steady state power mode in that the processor <NUM>, in the turbo power mode, can operate at one or more of the following compared to the steady state power mode: a higher voltage, a higher current, a higher power, a higher load capacity, or a higher clock speed. Consequently, when in the turbo power mode, the processor <NUM> can operate with greater performance and can perform more processor-intensive computations (e.g., for gaming applications).

In some instances (e.g., as in the example of <FIG>), there may be a transition period ΔT between an end of the turbo power mode and a commencement of the steady state power mode. The processor <NUM> may be in the steady state power mode for a second operating time period T<NUM>. When in the steady state power mode, the processor <NUM> may operate at or below the TDP specifications (e.g., at a sustained power state). In general, the first operating time period T<NUM> is shorter than the second operating time period T<NUM>, since the turbo power mode may be restricted to one or more portions of the processor <NUM> in a given thermal envelope (e.g., where the processor <NUM> includes, or is, a multicore processor). Theoretically, the second operating time period T<NUM> may be indefinitely long (e.g., the the processor <NUM> can operate at the processor sustained power indefinitely).

When in the steady state power mode, the processor sustained power may be in a range from about <NUM> Watts (W) to about <NUM> W (e.g., about <NUM> W), although other ranges are possible in other instances. For example, the processor sustained power may be different for chipsets of different generations, and, in such instances, the processor sustained power can be in one or more of the following ranges: from about <NUM> W to about <NUM> W; from about <NUM> W to about <NUM> W; from about <NUM> W to about <NUM> W; from about <NUM> W to about <NUM> W; or from about <NUM> W to about <NUM> W. In some instances, when in the turbo power mode, the processor <NUM> may operate at a power that is about twice (e.g., in a range from about <NUM> times to about <NUM> times) the processor sustained power. For example, the power consumed by the processor <NUM> when it is in the turbo power mode may be in a range from about <NUM> W to about <NUM> W (e.g., about <NUM> W), although other ranges are possible in other instances. For example, the power consumed by the processor <NUM> when it is in the turbo power mode may be different for chipsets of different generations, and turbo power can be in one or more of the following ranges in some instances: from about <NUM> W to about <NUM> W; from about <NUM> W to about <NUM> W; from about <NUM> W to about <NUM> W; or from about <NUM> W to about <NUM> W. The power unit <NUM> may be configured to power the processor <NUM> when it is in the turbo power mode and the steady state power mode.

The graph <NUM> illustrates a theoretical graph in which transitions from one power level to another power level are instantaneous. <FIG> also shows a graph <NUM> that illustrates real world transitions from one power level to another. <FIG> also shows a graph <NUM> that illustrates the average power as a function of time. As seen in <FIG>, although the instantaneous power may exceed the TDP specifications during the turbo power mode and the transition period ΔT, the average power of the processor <NUM> is within the TDP specifications.

Heat is generated by the processor <NUM> when the processor <NUM> is in operation (e.g., regardless of whether in the turbo power mode or the steady state power mode). At the same time, due to prescribed size, shape, and other physical specifications of the electronic device <NUM>, the electronic device <NUM> may be restricted to having a single vapor chamber to dissipate heat effectively and efficiently from the processor <NUM> when the processor <NUM> is operating in the turbo power mode and in the steady state power mode.

<FIG> is a diagram showing an exploded three-dimensional view of an example vapor chamber <NUM> that may be included in an electronic device, according to an implementation of the present disclosure. <FIG> also shows a frame of reference <NUM> having three orthogonal axes. The frame of reference <NUM> includes a first axis in a first direction (e.g., the X-direction), a second axis in a second direction (e.g., the Y-direction), and a third axis in a third direction (e.g., the Z-direction). The first, second, and third directions are perpendicular to each other. <FIG> is a diagram showing a top-down view of the example vapor chamber <NUM> shown in <FIG>, according to an implementation of the present disclosure. <FIG> is a diagram showing a cross-sectional view of the example vapor chamber <NUM> shown in <FIG>, according to an implementations of the present disclosure. <FIG> also shows the relative positions of the vapor chamber <NUM>, the processor <NUM>, and the circuit board <NUM>, according to an implementation of the present disclosure. The cross-sectional view shown in <FIG> is taken along the line A-A shown in <FIG> and <FIG>.

In contrast to existing vapor chambers (which are optimized for dissipating heat from a processor that is either in a turbo power mode or in a normal operation/steady state power mode, but not both), the vapor chamber <NUM> proposed in this disclosure is optimized to efficiently dissipate heat from the processor <NUM> when the processor <NUM> is in a normal operation/steady state power mode and to efficiently dissipate heat from the processor <NUM> when the processor <NUM> is in a turbo power mode. As an example, as described in further detail below, the vapor chamber <NUM> can modulate the volume of working fluid used in the evaporation-condensation cycles based on the operating state of the processor <NUM>. Furthermore, although various aspects of the present disclosure describe efficiently dissipate heat from the processor <NUM> based on the operating state of the processor <NUM>, the vapor chamber <NUM> can be used for any component in an electronic device that has multiple operating states and that generates heat at each operating state.

As seen in <FIG>, <FIG>, and <FIG>, the vapor chamber <NUM> includes a cover portion <NUM> and a base portion <NUM>. In some implementations, the cover portion <NUM> and the base portion <NUM> may be formed from one or more materials having high thermal conductivity (e.g., a material having thermal conductivity greater than or equal to about <NUM> W/m K). Example materials having high thermal conductivity include copper and aluminum. In some implementations, each of the cover portion <NUM> and the base portion <NUM> has a thickness T (e.g., measured in the third direction) that may be greater than or equal to about <NUM> (e.g., in a range from about <NUM> to about <NUM>).

The cover portion <NUM> has a first surface 402A and a second surface 402B opposite the first surface 402A. Similarly, the base portion <NUM> has a first surface 404A and a second surface 404B opposite the first surface 404A. The first surfaces 402A, 404A of the cover and base portions <NUM>, <NUM> may define the exterior surfaces of the vapor chamber <NUM>. In various aspects, the cover portion <NUM> and the base portion <NUM> may be secured to each other to form a sealed, interior enclosure under vacuum pressure that contains one or more capillary structures and a working fluid under pressure that circulates within a sealed enclosure. For example, as seen in <FIG>, a sealed enclosure <NUM> may be defined by the second surface 402B of the cover portion <NUM> and the second surface 404B of the base portion <NUM>.

As seen in <FIG>, in some aspects, the cover portion <NUM> includes through holes <NUM>, and the base portion <NUM> includes through holes <NUM> that are aligned to the through holes <NUM>. In some instances, the through holes <NUM>, <NUM> can accommodate screws <NUM> that can secure the cover portion <NUM> and the base portion <NUM> to each other, thereby forming the sealed enclosure <NUM> of the vapor chamber <NUM>. In some instances, the circuit board <NUM> may also include through holes that are aligned to the through holes <NUM>, <NUM>. In such instances, the screws <NUM> may also be used to secure the vapor chamber <NUM> to the circuit board <NUM> such that the processor <NUM> is in physical contact with the surface 402A of the cover portion <NUM> (e.g., as seen in the example of <FIG>).

The vapor chamber <NUM> (e.g., the sealed enclosure <NUM> of the vapor chamber <NUM>) may include a main (e.g., central) chamber <NUM>. In some implementations, the processor <NUM> is disposed over a portion of the main chamber <NUM> (e.g., such that the processor <NUM> is in physical contact with the surface 402A of the cover portion <NUM>). The main chamber <NUM> may have a dimension D1 in the first direction (e.g., the farthest lateral extent in the X-direction) and a dimension D2 in the second direction (e.g., the farthest lateral extent in the Y-direction). In some implementations, the dimension D1 may be in a range from about <NUM> to about <NUM>, and the dimension D2 may be in a range from about <NUM> to about <NUM>. The vapor chamber <NUM> may also include a first elongate chamber 604A and a second elongate chamber 604B that extend laterally (e.g., in opposite directions along the second axis) from opposite sides of the central chamber <NUM>. Each of the elongate chambers 604A, 604B may have a dimension D3 in the first direction (e.g., the farthest lateral extent in the X-direction) and a dimension D4 in the second direction (e.g., the farthest lateral extent in the Y-direction). In some implementations, the dimension D3 may be in a range from about <NUM> to about <NUM>, and the dimension D4 may be in a range from about <NUM> to about <NUM>. Furthermore, a ratio of the dimension D2 to the dimension D4 may be in a range from about <NUM> to about <NUM>.

In some implementations, the vapor chamber <NUM> includes a first capillary structure <NUM> that lines the second surface 402B of the cover portion <NUM>, and a second capillary structure <NUM> that lines the first surface 404B of the base portion <NUM>. The surface 402B of the cover portion <NUM> may be referred to as a first interior surface of the sealed enclosure <NUM>, and the surface 404B of the base portion <NUM> may be referred to as a second interior surface of the sealed enclosure <NUM>. The first and second capillary structures <NUM>, <NUM> may be separated from each other (e.g., in the third direction) by an air gap <NUM>. In some instances, the first and second capillary structures <NUM>, <NUM> is evenly (e.g., conformally) formed over an entirety of the surfaces 402B, 404B, respectively, such that the first and second capillary structures <NUM>, <NUM> are disposed in the main chamber <NUM>, the first elongate chamber 604A, and the second elongate chamber 604B of the sealed enclosure <NUM>.

The first and second capillary structures <NUM>, <NUM> may be porous wick structures configured to circulate a working fluid in the sealed enclosure <NUM> by capillary forces. In some instances, the first and second capillary structures <NUM>, <NUM> may be formed from one or more metals (e.g., copper) and may be in a form of a sintered metal-containing powder, one or more layers of a metal-containing mesh, one or more layers of a metal-containing foam, a metal-containing fiber structure, or a combination thereof. Furthermore, the working fluid used in the sealed enclosure <NUM> may be water (e.g., distilled water), although other types of working fluid are possible (e.g., a refrigerant, alcohol, ammonia, etc.). In some implementations, the first and second capillary structures <NUM>, <NUM> are saturated with the working fluid, and the cover and base portions <NUM>, <NUM> (e.g., having the saturated first and second capillary structures <NUM>, <NUM> lining the surfaces 402B, 404B thereof) are secured to each other to form the sealed enclosure <NUM>.

The vapor chamber <NUM> may also include a heat dissipation structure (e.g., a first fin structure 610A and a second fin structure 610B) formed on an exterior surface of the vapor chamber <NUM> for diffusing heat from the vapor chamber <NUM> to the ambient/outside environment. The fin structures 610A, 610B may be formed from one or more materials having high thermal conductivity (e.g., a material having thermal conductivity greater than or equal to about <NUM> W/m K). Example materials having high thermal conductivity include copper and aluminum. The fin structures 610A 610B shown in <FIG>, <FIG>, and <FIG> are merely exemplary, and other types, numbers, arrangements, etc. of fin structures may be possible in other implementations. In some instances, such as in the example of <FIG>, <FIG>, and <FIG>, the fin structures closest to the processor <NUM> may define the boundaries between the main chamber <NUM> and the elongate chambers 604A, 604B. For example, as seen in the example of <FIG>, the fin structure 610A-<NUM> defines a boundary between the main chamber <NUM> and the first elongate chamber 604A, and the fin structure 610B-<NUM> defines a boundary between the main chamber <NUM> and the second elongate chamber 604B. In some instances, the dimensions D2 and D4 may be measured relative to the boundaries between the main chamber <NUM> and the elongate chambers 604A, 604B, as seen in <FIG> and <FIG>.

The fin structures 610A, 610B may be disposed on either the first surface 402A of the cover portion <NUM> or the first surface 404A of the base portion <NUM>. In some instances, the fin structures 610A, 610B may be disposed on both the first surface 402A of the cover portion <NUM> and the first surface 404A of the base portion <NUM> (e.g., as seen in the example of <FIG>, which shows a cross-sectional view of an example vapor chamber <NUM>, according to another implementation of the present disclosure). In the example shown in <FIG>, the first fin structure 610A may be positioned lateral to the processor <NUM> (e.g., in the second direction) and over a portion of the first elongate chamber 604A. Similarly, the second fin structure 610B may be positioned lateral to the processor <NUM> (e.g., in the second direction) and over a portion of the second elongate chamber 604B. In some implementations, a dimension D5 of the first and second fin structures 610A, 610B in the second direction (e.g., the farthest lateral extent in the Y-direction) may be less than the dimension D4. Consequently, as seen in the examples of <FIG> and <FIG>, a portion of the first elongate chamber 604A extends laterally in the second direction beyond a footprint of the first fin structure 610A, and a portion of the second elongate chamber 604B extends laterally in the second direction beyond a footprint of the second fin structure 610B.

The portions of the first and second elongate chambers 604A, 604B that extend laterally beyond (e.g., outside of) the footprints of the heat dissipation structure (e.g., first and second fin structures 610A, 610B, respectively) can be referred to as distal portions of the first and second elongate chambers 604A, 604B. The distal portions of the first and second elongate chambers 604A, 604B can serve as reservoirs 612A, 612B that store an excess volume of the working fluid (e.g., in the liquid state). For example, portions of the capillary structures <NUM>, <NUM> that are disposed in the distal portions of the first and second elongate chambers 604A, 604B can serve as reservoirs 612A, 612B. In some implementations, these portions of the first and second elongate chambers 604A, 604B are suitable as reservoirs <NUM> since these portions may be the coolest portions of the vapor chamber <NUM>, thus facilitating the storage of a liquid medium (e.g., working fluid in the liquid state) in the portions of the first and second capillary structures <NUM>, <NUM> disposed in the reservoirs 612A, 612B.

When the processor <NUM> is operating in the normal operation/steady state power mode, the vapor chamber <NUM> is effective in dissipating the heat generated by the processor <NUM> by circulating a first volume (e.g., a nominal volume) of the working fluid within the sealed enclosure <NUM> (e.g., through repeated evaporation-condensation cycles), without tapping the excess volume of the working fluid (e.g., in the liquid state) stored in the reservoirs 612A, 612B and without increasing the thermal resistance of the vapor chamber <NUM> (e.g., since the excess volume of the working fluid is stored in the reservoirs 612A, 612B and not used in the repeated evaporation-condensation cycles). Conversely, when the processor <NUM> is operating in the turbo power mode, the vapor chamber <NUM> is effective in dissipating the higher amount of heat generated by the processor <NUM> by drawing the excess volume of the working fluid from the reservoirs 612A, 612B via capillary action (e.g., working fluid in the liquid state stored in the portions of the first and second capillary structures <NUM>, <NUM> disposed in the reservoirs 612A, 612B), such that all the working fluid in the vapor chamber <NUM> (e.g., the nominal volume of the working fluid and the excess volume of the working fluid) is circulated within the sealed enclosure <NUM> (e.g., through repeated evaporation-condensation cycles).

In some instances, the amount of the working fluid used in the vapor chamber <NUM> may be in a range from about <NUM> gram to about <NUM> grams (e.g., from about <NUM> to about <NUM> in implementations where the working fluid is water). In some implementations, the nominal volume of the working fluid may be substantially equal to the excess volume of the working fluid. Consequently, twice the volume of working fluid may be circulated within the sealed enclosure <NUM> (e.g., through repeated evaporation-condensation cycles) when the processor <NUM> is operating in the turbo power mode compared to when the processor <NUM> is operating in the normal operation/steady state power mode. In some instances, the nominal volume of the working fluid may be in a range from about <NUM> to about <NUM> (e.g., about <NUM> when the processor <NUM> is operating at a steady state power of about <NUM> W). In such instances, the excess volume of the working fluid may also be in a range from about <NUM> to about <NUM> (e.g., so that about <NUM> is circulated within the sealed enclosure <NUM> when the processor <NUM> is operating at a turbo power of about <NUM> W).

<FIG> is a diagram showing an example flow of working fluid in the vapor chamber <NUM> when the processor <NUM> is operating in the normal operation/steady state power mode, according to an implementation of the present disclosure. <FIG> is a diagram showing an example flow of working fluid in the vapor chamber <NUM> when the processor <NUM> is operating in the turbo power mode, according to an implementation of the present disclosure. As discussed in <FIG>, the processor <NUM> may initially be in a sleep or low power state (e.g., in time period T<NUM> shown in <FIG>). When the processor <NUM> is in the sleep/low power state, the vapor chamber <NUM> is not in operation and therefore, the working fluid is not experiencing evaporation or condensation within the sealed enclosure <NUM>. Consequently, the entire volume of the working fluid within the sealed enclosure <NUM> is in a liquid state. Furthermore, the working fluid evenly saturates the first and second capillary structures <NUM>, <NUM>. Additionally, there is an equal, equilibrium vapor pressure experienced across the entire volume of the air gap <NUM>.

Referring to <FIG>, when the processor <NUM> is in the normal operation/steady state power mode (e.g., in time period T<NUM> shown in <FIG>), the portion <NUM> of the vapor chamber <NUM> that is in physical contact with the processor <NUM> increases in temperature. As a result, the working fluid at the portion <NUM> (e.g., in the first capillary structure <NUM> and in the liquid state) absorbs the heat from the processor <NUM> and vaporizes. The latent heat of vaporization absorbed by the working fluid at the portion <NUM> reduces the temperature at the portion <NUM>, thus dissipating heat from the processor <NUM>. As the vapor travels through the center of the sealed enclosure <NUM> (e.g., illustrated by arrows <NUM>), it leaves the evaporation zone (e.g., an area in the vicinity of the processor <NUM>) and enters a condensation zone (e.g., an area in the vapor chamber <NUM> away from the processor <NUM>). In the condensation zone, the vapor condenses, thus releasing the latent heat into the walls of the vapor chamber <NUM>. In the example of <FIG>, the vapor is captured by, and condenses into, portions of the first and second capillary structures <NUM>, <NUM> that are outside the reservoirs 612A, 612B. As vaporization of the working fluid at the portion <NUM> occurs, working fluid (in the liquid state) is drawn from the condensation zone to the evaporation zone through the first and second capillary structures <NUM>, <NUM> via capillary action (e.g., illustrated by arrows <NUM>). This evaporation-condensation cycle is repeated while the processor <NUM> is in the normal operation/steady state power mode. In the normal operation/steady state power mode, the nominal volume of working fluid is used in the evaporation-condensation cycles, and the excess volume of the working fluid (e.g., in the liquid state) that is stored in the reservoirs 612A, 612B is left unused since the increased vapor pressure in the evaporation zone causes the fluid transfer (e.g., illustrated by arrows <NUM> and <NUM>) to reach an equilibrium before the working fluid in the reservoirs 612A, 612B is used.

Referring to <FIG>, when the processor <NUM> is in the turbo power mode (e.g., in time period T<NUM> shown in <FIG>), the portion <NUM> of the vapor chamber <NUM> that is in physical contact with the processor <NUM> increases by a greater amount of temperature compared to when the processor <NUM> is in the normal operation/steady state power mode. The working fluid at the portion <NUM> (e.g., in the first capillary structure <NUM> and in the liquid state) absorbs the heat from the processor <NUM> and vaporizes. The latent heat of vaporization absorbed by the working fluid at the portion <NUM> reduces the temperature at the portion <NUM>, thus dissipating heat from the processor <NUM>. As the vapor travels through the center of the sealed enclosure <NUM> (e.g., illustrated by arrows <NUM>), it leaves the evaporation zone and enters the condensation zone. The vaporization of the working fluid at the portion <NUM> when the processor <NUM> is in the turbo power mode causes a greater volume of working fluid (in the liquid state) to be drawn from the condensation zone to the evaporation zone through the first and second capillary structures <NUM>, <NUM> via capillary action (e.g., compared to the case of <FIG> and as illustrated by arrows <NUM>). This increase in the volume of working fluid is provided by the excess volume of the working fluid (e.g., in the liquid state) that is stored in the reservoirs 612A, 612B. In the turbo power mode, the entire volume of working fluid in the vapor chamber <NUM> is used in the evaporation-condensation cycles since the greater vapor pressure in the evaporation zone (e.g., compared to the case of <FIG>) causes the fluid transfer (e.g., illustrated by arrows <NUM> and <NUM>) to reach an equilibrium when the excess volume of the working fluid in the reservoirs 612A, 612B is also used in the evaporation-condensation cycles.

Consequently, the vapor chamber <NUM> can modulate the volume of working fluid used in the evaporation-condensation cycles based on the operating state of the processor <NUM>. The vapor chamber <NUM> can therefore be used to efficiently dissipate heat from the processor <NUM> when the processor <NUM> is in a normal operation/steady state power mode and to efficiently dissipate heat from the processor <NUM> when the processor <NUM> is in a turbo power mode. Therefore, in contrast to existing vapor chambers, the vapor chamber <NUM> can be used to dissipate heat when the processor <NUM> is in a turbo power mode (e.g., since both a nominal volume and an excess volume of the working fluid are used in the evaporation-condensation cycles when in the turbo power mode) and can have a lower thermal resistance when the processor <NUM> is in a normal operation/steady state power mode (e.g., since the nominal volume of the working fluid is used in the evaporation-condensation cycles when in the normal operation/steady state power mode).

In some implementations, the internal structure of the vapor chamber <NUM> (e.g. as illustrated in the example of <FIG>) may be modified as seen in <FIG>, <FIG>, and <FIG>. Similar to the vapor chamber <NUM> in the example of <FIG>, in each of the examples shown in <FIG>, <FIG>, and <FIG>, the vapor chamber <NUM> can modulate the volume of working fluid used in the evaporation-condensation cycles based on the operating state of the processor <NUM>, thus allowing the vapor chamber <NUM> to be used to efficiently dissipate heat from the processor <NUM> when the processor <NUM> is in a normal operation/steady state power mode and to efficiently dissipate heat from the processor <NUM> when the processor <NUM> is in a turbo power mode.

<FIG> is a diagram showing a cross-sectional view of the example vapor chamber <NUM> shown in <FIG>, according to another implementation of the present disclosure. <FIG> is a diagram showing an example flow of working fluid in the example vapor chamber of <FIG> when the processor <NUM> is operating in the normal operation/steady state power mode, according to an implementation of the present disclosure. <FIG> is a diagram showing an example flow of working fluid in the example vapor chamber of <FIG> when the processor <NUM> is operating in the turbo power mode, according to an implementation of the present disclosure. In contrast to the example shown in <FIG>, the vapor chamber <NUM> shown in <FIG> includes a third capillary structure <NUM> that is attached to the cover portion <NUM> of the vapor chamber <NUM>. Specifically, the third capillary structure <NUM> may be attached to (e.g., and be in physical contact with) the first capillary structure <NUM> and may be separated from the second capillary structure by the air gap <NUM>. Portions of the capillary structures <NUM>, <NUM>, <NUM> that are disposed in the distal portions of the first and second elongate chambers 604A, 604B can serve as reservoirs 612A, 612B. In some implementations, the third capillary structure <NUM> may be formed from one or more metals (e.g., copper) and may be in a form of a sintered metal-containing powder, one or more layers of a metal-containing mesh, one or more layers of a metal-containing foam, a metal-containing fiber structure, or a combination thereof. As an example, the third capillary structure <NUM> may be a metal-containing fiber structure, while the first capillary structure <NUM> may be in the form of a sintered metal-containing powder, one or more layers of a metal-containing mesh, or one or more layers of a metal-containing foam. In some instances, the first, second, and third capillary structures <NUM>, <NUM>, <NUM> are saturated with the working fluid, and the cover and base portions <NUM>, <NUM> (e.g., having the saturated capillary structures <NUM>, <NUM>, <NUM>) are secured to each other to form the sealed enclosure <NUM>.

As seen in <FIG>, when the processor <NUM> is in the normal operation/steady state power mode, the portion <NUM> of the vapor chamber <NUM> that is in physical contact with the processor <NUM> increases in temperature. As a result, the working fluid at the portion <NUM> (e.g., in the first and third capillary structures <NUM>, <NUM> and in the liquid state) absorbs the heat from the processor <NUM> and vaporizes. The latent heat of vaporization absorbed by the working fluid at the portion <NUM> reduces the temperature at the portion <NUM>, thus dissipating heat from the processor <NUM>. As the vapor travels through the center of the sealed enclosure <NUM> (e.g., illustrated by arrows <NUM>), it leaves the evaporation zone (e.g., an area in the vicinity of the processor <NUM>) and enters a condensation zone (e.g., an area in the vapor chamber <NUM> away from the processor <NUM>). In the condensation zone, the vapor condenses, thus releasing the latent heat into the walls of the vapor chamber <NUM>. In the example of <FIG>, the vapor is captured by, and condenses into, portions of the second and third capillary structures <NUM>, <NUM> that are outside the reservoirs 612A, 612B. As vaporization of the working fluid at the portion <NUM> occurs, working fluid (in the liquid state) is drawn from the condensation zone to the evaporation zone through the capillary structure <NUM>, <NUM>, <NUM> via capillary action (e.g., illustrated by arrows <NUM>). This evaporation-condensation cycle is repeated while the processor <NUM> is in the normal operation/steady state power mode. As in the example shown in <FIG>, in the normal operation/steady state power mode, the nominal volume of working fluid is used in the evaporation-condensation cycles, and the excess volume of the working fluid (e.g., in the liquid state) that is stored in the reservoirs 612A, 612B is left unused since the increased vapor pressure in the evaporation zone causes the fluid transfer (e.g., illustrated by arrows <NUM> and <NUM>) to reach an equilibrium before the working fluid in the reservoirs 612A, 612B is used.

Referring to <FIG>, when the processor <NUM> is in the turbo, the portion <NUM> of the vapor chamber <NUM> that is in physical contact with the processor <NUM> increases by a greater amount of temperature compared to when the processor <NUM> is in the normal operation/steady state power mode. The working fluid at the portion <NUM> (e.g., in the first and third capillary structures <NUM>, <NUM> and in the liquid state) absorbs the heat from the processor <NUM> and vaporizes. The latent heat of vaporization absorbed by the working fluid at the portion <NUM> reduces the temperature at the portion <NUM>, thus dissipating heat from the processor <NUM>. As the vapor travels through the center of the sealed enclosure <NUM> (e.g., illustrated by arrows <NUM>), it leaves the evaporation zone and enters the condensation zone. The vaporization of the working fluid at the portion <NUM> when the processor <NUM> is in the turbo power mode causes a greater volume of working fluid (in the liquid state) to be drawn from the condensation zone to the evaporation zone through the capillary structures <NUM>, <NUM>, <NUM> via capillary action (e.g., compared to the case of <FIG> and as illustrated by arrows <NUM>). This increase in the volume of working fluid is provided by the excess volume of the working fluid (e.g., in the liquid state) that is stored in the reservoirs 612A, 612B. In the turbo power mode, the entire volume of working fluid in the vapor chamber <NUM> is used in the evaporation-condensation cycles since the greater vapor pressure in the evaporation zone (e.g., compared to the case of <FIG>) causes the fluid transfer (e.g., illustrated by arrows <NUM> and <NUM>) to reach an equilibrium when the excess volume of the working fluid in the reservoirs 612A, 612B is also used in the evaporation-condensation cycles.

<FIG> is a diagram showing a cross-sectional view of the example vapor chamber <NUM> shown in <FIG>, according to yet another implementation of the present disclosure. <FIG> is a diagram showing an example flow of working fluid in the example vapor chamber of <FIG> when the processor <NUM> is operating in the normal operation/steady state power mode, according to an implementation of the present disclosure. <FIG> is a diagram showing an example flow of working fluid in the example vapor chamber of <FIG> when the processor <NUM> is operating in the turbo power mode, according to an implementation of the present disclosure. In contrast to the examples shown in <FIG> and <FIG>, the reservoirs 612A, 612B shown in <FIG> have a height H1 that is different from a height H2 of the main chamber <NUM>. As shown in the examples of <FIG>, the heights H1 and H2 may define distances between the surfaces 402B, 404B of the cover and base portions <NUM>, <NUM> of the vapor chamber <NUM> (e.g., as measured in the third direction). The working principle of the vapor chamber <NUM> shown in <FIG> may be similar to the working principle of the vapor chamber <NUM> shown in <FIG>.

Specifically, as seen in <FIG>, when the processor <NUM> is in the normal operation/steady state power mode, the portion <NUM> of the vapor chamber <NUM> that is in physical contact with the processor <NUM> increases in temperature. As a result, the working fluid at the portion <NUM> (e.g., in the first and third capillary structures <NUM>, <NUM> and in the liquid state) absorbs the heat from the processor <NUM> and vaporizes. The latent heat of vaporization absorbed by the working fluid at the portion <NUM> reduces the temperature at the portion <NUM>, thus dissipating heat from the processor <NUM>. As the vapor travels through the center of the sealed enclosure <NUM> (e.g., illustrated by arrows <NUM>), it leaves the evaporation zone (e.g., an area in the vicinity of the processor <NUM>) and enters a condensation zone (e.g., an area in the vapor chamber <NUM> away from the processor <NUM>). In the condensation zone, the vapor condenses, thus releasing the latent heat into the walls of the vapor chamber <NUM>. In the example of <FIG>, the vapor is captured by, and condenses into, portions of the second and third capillary structures <NUM>, <NUM> that are outside the reservoirs 612A, 612B. As vaporization of the working fluid at the portion <NUM> occurs, working fluid (in the liquid state) is drawn from the condensation zone to the evaporation zone through the capillary structure <NUM>, <NUM>, <NUM> via capillary action (e.g., illustrated by arrows <NUM>). This evaporation-condensation cycle is repeated while the processor <NUM> is in the normal operation/steady state power mode. As in the example shown in <FIG>, in the normal operation/steady state power mode, the nominal volume of working fluid is used in the evaporation-condensation cycles, and the excess volume of the working fluid (e.g., in the liquid state) that is stored in the reservoirs 612A, 612B is left unused since the increased vapor pressure in the evaporation zone causes the fluid transfer (e.g., illustrated by arrows <NUM> and <NUM>) to reach an equilibrium before the working fluid in the reservoirs 612A, 612B is used.

<FIG> is a diagram showing a cross-sectional view of the example vapor chamber <NUM> shown in <FIG>, according to a further implementation of the present disclosure. <FIG> is a diagram showing an example flow of working fluid in the example vapor chamber of <FIG> when the processor <NUM> is operating in the normal operation/steady state power mode, according to an implementation of the present disclosure. <FIG> is a diagram showing an example flow of working fluid in the example vapor chamber of <FIG> when the processor <NUM> is operating in the turbo power mode, according to a further implementation of the present disclosure. In contrast to the example shown in <FIG>, the reservoirs 612A, 612B shown in <FIG> accommodate a reservoir capillary structure <NUM> that is disposed between (and that may be in physical contact with) the third capillary structure <NUM> and the second capillary structure <NUM>. Portions of the capillary structures <NUM>, <NUM>, <NUM>, <NUM> that are disposed in the distal portions of the first and second elongate chambers 604A, 604B can serve as reservoirs 612A, 612B. The reservoir capillary structure <NUM> may be formed from one or more metals (e.g., copper) and may be in a form of a sintered metal-containing powder, one or more layers of a metal-containing mesh, one or more layers of a metal-containing foam, a metal-containing fiber structure, or a combination thereof. In some instances, the first, second, third, and reservoir capillary structures <NUM>, <NUM>, <NUM>, <NUM> are saturated with the working fluid, and the cover and base portions <NUM>, <NUM> (e.g., having the saturated capillary structures <NUM>, <NUM>, <NUM>, <NUM>) are secured to each other to form the sealed enclosure <NUM>.

As seen in <FIG>, when the processor <NUM> is in the normal operation/steady state power mode, the portion <NUM> of the vapor chamber <NUM> that is in physical contact with the processor <NUM> increases in temperature. As a result, the working fluid at the portion <NUM> (e.g., in the first and third capillary structures <NUM>, <NUM> and in the liquid state) absorbs the heat from the processor <NUM> and vaporizes. The latent heat of vaporization absorbed by the working fluid at the portion <NUM> reduces the temperature at the portion <NUM>, thus dissipating heat from the processor <NUM>. As the vapor travels through the center of the sealed enclosure <NUM> (e.g., illustrated by arrows <NUM>), it leaves the evaporation zone (e.g., an area in the vicinity of the processor <NUM>) and enters a condensation zone (e.g., an area in the vapor chamber <NUM> away from the processor <NUM>). In the condensation zone, the vapor condenses, thus releasing the latent heat into the walls of the vapor chamber <NUM>. In the example of <FIG>, the vapor is captured by, and condenses into, portions of the second and third capillary structures <NUM>, <NUM> that are outside the reservoirs 612A, 612B. As vaporization of the working fluid at the portion <NUM> occurs, working fluid (in the liquid state) is drawn from the condensation zone to the evaporation zone through the capillary structure <NUM>, <NUM>, <NUM> via capillary action (e.g., illustrated by arrows <NUM>). This evaporation-condensation cycle is repeated while the processor <NUM> is in the normal operation/steady state power mode. As in the example shown in <FIG>, in the normal operation/steady state power mode, the nominal volume of working fluid is used in the evaporation-condensation cycles, and the excess volume of the working fluid (e.g., in the liquid state) that is stored in the reservoir capillary structure <NUM> located in the reservoirs 612A, 612B is left unused since the increased vapor pressure in the evaporation zone causes the fluid transfer (e.g., illustrated by arrows <NUM> and <NUM>) to reach an equilibrium before the working fluid in the reservoir capillary structure <NUM> is used.

Referring to <FIG>, when the processor <NUM> is in the turbo power mode, the portion <NUM> of the vapor chamber <NUM> that is in physical contact with the processor <NUM> increases by a greater amount of temperature compared to when the processor <NUM> is in the normal operation/steady state power mode. The working fluid at the portion <NUM> (e.g., in the first and third capillary structures <NUM>, <NUM> and in the liquid state) absorbs the heat from the processor <NUM> and vaporizes. The latent heat of vaporization absorbed by the working fluid at the portion <NUM> reduces the temperature at the portion <NUM>, thus dissipating heat from the processor <NUM>. As the vapor travels through the center of the sealed enclosure <NUM> (e.g., illustrated by arrows <NUM>), it leaves the evaporation zone and enters the condensation zone. The vaporization of the working fluid at the portion <NUM> when the processor <NUM> is in the turbo power mode causes a greater volume of working fluid (in the liquid state) to be drawn from the condensation zone to the evaporation zone from the reservoir capillary structure <NUM> through the capillary structures <NUM>, <NUM>, <NUM> via capillary action (e.g., compared to the case of <FIG> and as illustrated by arrows <NUM>). This increase in the volume of working fluid is provided by the excess volume of the working fluid (e.g., in the liquid state) that is stored in the reservoir capillary structure <NUM>. In the turbo power mode, the entire volume of working fluid in the vapor chamber <NUM> is used in the evaporation-condensation cycles since the greater vapor pressure in the evaporation zone (e.g., compared to the case of <FIG>) causes the fluid transfer (e.g., illustrated by arrows <NUM> and <NUM>) to reach an equilibrium when the excess volume of the working fluid in the reservoir capillary structure <NUM> is also used in the evaporation-condensation cycles.

<FIG> is a flowchart illustrating a process <NUM> for designing a vapor chamber having reservoirs and configured to modulate a volume of working fluid used in evaporation-condensation cycles based on an operating state of a processor, according to an implementation of the present disclosure. The process <NUM> may include additional or different operations, and the operations shown in <FIG> may be performed in the order shown or in another order. In some cases, one or more of the operations shown in <FIG> are implemented as processes that include multiple operations, sub-processes for other types of routines. In some cases, operations can be combined, performed in another order, performed in parallel, iterated or otherwise repeated or performed in another manner.

At <NUM>, a vapor chamber is designed for a processor in the normal operation/steady state power mode. A result of operation <NUM> is a determination of the dimensions of the vapor chamber (e.g., the dimensions D1, D2, D3, D4, shown in <FIG> and the thickness T shown in <FIG>). Another result of the operation <NUM> is a determination of the nominal volume of the working fluid for the vapor chamber.

At <NUM>, the vapor chamber designed at <NUM> is used to determine the total volume of the working fluid needed when the processor in the turbo power mode.

At <NUM>, one or more reservoirs (e.g., the reservoirs 612A, 612B) are designed to accommodate the excess volume of working fluid (e.g., which may be given by the difference between the total volume of the working fluid needed when the processor in the turbo power mode and the nominal volume of the working fluid). At <NUM>, the reservoir(s) are designed to comply with specifications regarding the electronic device <NUM> (e.g., system space requirements).

At <NUM>, one or more capillary structures are chosen and designed for the reservoir(s) (e.g., the reservoirs 612A, 612B). At <NUM>, the vapor chamber having the reservoir(s) and the capillary structure(s) therein is tested with the processor in the normal operation/steady state power mode and the processor in the turbo power mode.

At <NUM>, a determination is made as to whether the test at <NUM> has passed. In response to a determination that the test at <NUM> has failed, operation <NUM> is repeated and another capillary structure is chosen and designed for the reservoir(s). Following the redesign of the capillary structure, the test at <NUM> and the determination at <NUM> are repeated. In response to a determination that the test at <NUM> has passed, the vapor chamber designed by operations <NUM>, <NUM>, <NUM>, <NUM>, <NUM> is then used (in <NUM>) for the electronic device <NUM> in order to modulate a volume of working fluid used in evaporation-condensation cycles based on an operating state of a processor.

Some of the subject matter and operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. Some of the subject matter described in this specification can be implemented as one or more computer programs, i.e., one or more modules of computer program instructions, encoded on a computer storage medium for execution by, or to control the operation of, data-processing apparatus. A computer storage medium can be, or can be included in, a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination of one or more of them. Moreover, while a computer storage medium is not a propagated signal, a computer storage medium can be a source or destination of computer program instructions encoded in an artificially generated propagated signal.

Some of the operations described in this specification can be implemented as operations performed by a data processing apparatus on data stored on one or more computer-readable storage devices or received from other sources.

A program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code).

Claim 1:
A vapor chamber (<NUM>), comprising:
a sealed enclosure (<NUM>) comprising:
a main chamber (<NUM>),
a first elongate chamber (604A) extending laterally from a first side of the main chamber; and
a second elongate chamber (604B) extending laterally from a second, opposite side of the main chamber;
a first capillary structure (<NUM>) lining a first interior surface of the sealed enclosure; and
a second capillary structure (<NUM>) lining a second, opposite interior surface of the sealed enclosure,
characterised in that distal portions (612A, 612B) of the first elongate chamber and the second elongate chamber are configured as reservoirs that store an excess volume of a working fluid in a liquid state when a heat source is in a first operating state and release the excess volume of the working fluid towards the main chamber when the heat source is in a second operating state.