TW201500711A - Microchannel heat sink having porous heat-sink elements and its heat-sink approach - Google Patents

Abstract

The present invention relates to a microchannel heat sink having porous heat- sink elements and its heat-sink approach. The microchannel heat sink comprises a base body within which a plurality of microchannels with an axial length located, wherein the microchannels run through the base body. Each of the microchannels includes an entrance end, an exit end, and a channel-shaped space which connects the entrance end and the exit end and has a first side and a second side located thereon. The microchannel heat sink further comprises a plurality of porous heat-sink element being located on the first and second sides of each channel-shaped space and forming a flow channel between two of the porous heat-sink elements. The porous heat-sink elements enhance the local convection of the fluid passing through the channel-shaped space, while the flow channel formed between two of the porous heat-sink elements reduces the pressure drop that needs more output power, so as to improve the heat dissipation efficiency and effect.

Description

Microchannel heat sink with porous heat sink and heat dissipation method thereof

The invention relates to a microchannel heat sink with a porous heat sink and a heat dissipating method thereof, in particular to a partial convection of a liquid passing through a porous material, and a porous material distribution in the microchannel to form a part The flow path, thereby reducing the voltage drop, avoids the need for a larger output power, to improve the heat dissipation performance of the micro flow path heat sink and its heat dissipation method.

With the rapid development of technology and the development of information, electronics, automation and network technologies, highly integrated micro-systems will become the key to the success of modern and future technologies, all of which use microelectronics as the basis for computing. However, the current process scale of microchips has gradually decreased from 0.35 μm to 65 nm. In the future, it will inevitably become more miniaturized. As the electronic components become smaller, the density of crystals will increase greatly. Often, the miniaturized electronic components will have more heat as the data they are responsible for computing and storing. It also increases. At the same time, as the size of the electronic component is smaller, the assembly density is also gradually increased, which tends to cause a higher heat flux density inside the wafer (it is expected that the generated heat flux density may be as high as 1000 W/cm ² ). Therefore, if the heat generated by the operation of the wafer cannot be removed in time, the internal temperature is inevitably increased, which will affect the stability and reliability of the wafer operation. Past research indicates that when the wafer temperature is around 70~80 °C, the reliability of operation will decrease by 5% for every 1 °C increase in temperature. Therefore, it is very urgent and important to solve the heat dissipation problem of microelectronic devices.

Various heat dissipation technologies are used today to thermally manage or dissipate wafers, such as fans, air conditioners, cold plates, heat sinks, and thermal contact surfaces. Among them, the conventional fan, air conditioner, and cold plate can only meet the heat dissipation requirement when the heat flux density is small. With the high-density assembled electronic components, the aforementioned heat dissipation method cannot load a higher heat load, and in view of this, Some companies have developed a "microchannel heat sink" such as the Republic of China Patent Bulletin No. M430821. The above-mentioned creation is a microchannel heat sink. The microchannel heat sink has at least a first-class channel inside, and the flow prop has a liquid inlet and a The liquid outlet, the cross-sectional area of the flow channel is tapered from the liquid inlet port toward the liquid outlet.

There is still a deficiency in the use of the previous case. The reason is that the former case is only a simple type of channel that is tapered, thus forming a large pressure drop. When the temperature of the unit heat source is too high, the tapered channel cannot be formed. Effectively increase local convection. Under the fixed input pump power, it is easy to cause the problem of poor heat dissipation.

In view of the above-mentioned shortcomings in the use of microchannel heat sinks, a manufacturer has developed a new type of patent publication No. M442534, "Microfluidic heat sink and heat sink", the aforementioned creation is a micro The flow channel heat dissipating device comprises: a heat dissipating block having a body and a plurality of auxiliary heat dissipating bodies, wherein the block body is internally provided with a plurality of micro flow channels, each of the plurality of micro flow channels having an inlet, an outlet and a circulation space. The inlet and the outlet are both connected to the circulation space, the number of auxiliary heat sinks are disposed in each of the flow spaces of the plurality of microchannels, and the plurality of auxiliary heat sinks are each formed with a plurality of holes; and a fluid controller is The pipeline is connected to the seat body and communicates with each of the flow spaces of the plurality of microchannels. The foregoing creation can reduce the thickness of the local boundary layer generated when the working fluid passes, so as to increase the fluidity mixing and convection and conduction. In turn, the heat energy is quickly taken away and the local heat dissipation effect is effectively improved.

There are still deficiencies in the use of the previous case, the reasons are:

1. In the previous case, although the auxiliary heat dissipation system is provided as a porous material, and the filling is disposed in each of the circulation spaces, the pressure drop in the circulation space increases as the fluid passes, resulting in a decrease in fluidity.

2. If the previous case is to reduce the pressure drop, it is necessary to increase the area of the circulation space, so that the volume of the micro-channel heat sink is increased, and the installation space needs to be redesigned.

3. Although the prior case provides an auxiliary heat sink disposed in the micro flow channel to increase the fluidity mixing and convection, the liquid needs to flow into the porous material to require a larger output rate to drive, resulting in an increase in cost.

Therefore, in order to further effectively solve the traditional microchannel heat sink can not effectively increase the local convection, it is easy to cause poor heat dissipation, and the provision of porous material in the microchannel heat sink can increase the fluid flow mixing and convection, but The pressure drop caused by the liquid flowing into the porous material requires a larger output power to drive, resulting in an increase in cost. The present inventors have made efforts to study and propose a microchannel heat sink having a porous heat sink, including: a body The internal micro-channels have an axial length, and the micro-channels respectively include an inlet end, an outlet end, and a channel space. The inlet end communicates the channel space to the outlet end, and the channel space is set. There is a first side and a second side; a plurality of porous heat sinks are disposed on the first side and the second side of each channel space, and form a first-class track between the two porous heat sinks.

Further, the plurality of microchannels are equidistantly spaced inside the housing.

Further, the first side and the second side are the inner walls of the microchannel, and the two porous heat sinks are respectively disposed on the first side and the second side, and are consistent with the axial length of the microchannel. The aforementioned flow path is formed between the two porous heat sinks.

Further, the porous heat dissipation system is sintered into copper, aluminum or iron into a minute long plate block.

Further, the porous heat sink had a hole permeability of 0.66 and a permeability of 2.47e-10 m ² .

Another object of the present invention is a microchannel heat dissipation method with a porous heat dissipating body, comprising: a microchannel heat sink having a porous heat sink as claimed in claim 1 disposed on a heat source body; The liquid circulates in each of the channel spaces of the microchannel heat sink; in the channel space, the liquid is simultaneously passed through the two porous heat sinks and the two porous heat sinks to form a flow passage therethrough, and the heat source is taken away from the microchannel Heat sink

Further, a flow controller is used to transport the liquid to circulate in each channel space of the microchannel heat sink;

Further, the liquid system is water.

The effect of the invention is:

1. The present invention moves the tropic by a liquid flowing through the space of the channel, and the liquid can be water. The viscosity is low, the thermal conductivity is high, and the cost is low, which is easy to obtain.

2. The microchannel of the present invention has a simple structure and a manufacturing technique that is not complicated.

3. The porous heat sink of the present invention has good heat conduction effect, and the heat source can be quickly conducted to the liquid, and then the heat source is taken away from the microchannel heat sink.

4. The porous heat dissipating body is respectively disposed on both sides of the channel space of the present invention, and a flow channel is formed between the two porous heat dissipating bodies, so that the liquid passes through the porous heat dissipating body and the flow channel respectively, and the flow channel portion can avoid the liquid only The pressure drop is increased by the porous heat sink, resulting in a decrease in fluidity.

5. The flow controller of the present invention can arbitrarily control the output of the working fluid, and provides the user with the pressure drop in the microchannel heat sink to avoid excessive cost waste.

In combination with the above technical features, the main effects of the microchannel heat sink of the present invention having a porous heat sink and the heat dissipation method thereof will be clearly shown in the following embodiments.

At present, the conventional microchannel heat sink is constructed as described in the sixth figure. Generally, the microchannel heat sink provides a heat sink (5) that can be matched with a fluid circulation system, and the heat sink (5) is placed in a heat source body. (54) The heat dissipation seat (5) is internally spaced apart by a plurality of passage spaces (53) each having an inlet end (51) and an outlet end (52), each connected by a pipeline. The fluid circulation system circulates the working liquid through the passage space (53) and carries the heat source absorbed by the heat sink (5), thereby achieving the purpose of heat dissipation, but the structure is only a simple channel When the working liquid is in contact with only the inner wall of the passage space (53), the working liquid only takes away part of the heat source.

Therefore, in order to solve the above problems, the present invention provides a microchannel heat sink with a porous heat sink and a heat dissipation method thereof. For the first embodiment of the present invention, please refer to the first figure, including:

a body (1) and a plurality of porous heat sinks (2), the base body (1) is internally equidistantly spaced apart by a plurality of microchannels (11) extending through, each microchannel (11) extending an axial length The microchannel (11) is provided with an inlet end (111), an outlet end (112) and a passage space (113), and the inlet end (111) circulates the passage space (113) to the outlet end (112), The passage space (113) is available for a working liquid (12) to be circulated therein, and the working liquid (12) is water.

As shown in the second figure, a first side (113A) and a second side (113B) are respectively disposed on the left and right sides of the inner wall of the channel space (113), and the two porous heat sinks (2) are taken. Placed on the first side (113A) and the second side (113B) respectively, and conform to the axial length of the microchannel (11), and a through hole is reserved between the two porous heat sinks (2) The flow channel (21), the porous heat sink (2) has a plurality of irregular holes (22) arranged to flow in the working liquid (12) to reduce the thickness of the local boundary layer and increase the mixing of the fluid. And further increase the local working fluid flow rate, and the porous heat sink (2) is a material having better thermal conductivity such as copper, aluminum, tantalum or iron. In this embodiment, each of the plurality of holes (22) of the porous heat sink (2) preferably has a porosity, that is, a total volume of the plurality of holes (22) occupies the total of the porous heat sink (2). The volume ratio is in the range of 0.55 to 0.85, and the permeability is 8.15e-11 to 2.71e-9 meters square, especially for the through holes of the plurality of holes (22) of the porous heat sink (2). The property is 0.85, and the permeability is 2.71×10 -9 m square. It can quickly pass the working liquid (12) and take away the heat energy to achieve better heat dissipation.

Referring to the third and fourth figures, the microchannel heat sink with the porous heat sink of the present invention is first placed on the surface of a heat source body (54), which is an electronic component and a semiconductor. Etc., a component having a high unit heat load, a flow controller (4) is connected to a pipeline to each channel space (113) of the microchannel heat sink, and the flow controller (4) adjusts the output power for output. a working fluid (12) of a suitable flow rate, which is discharged from the flow controller (4) and flows into the inlet end (111), while the microchannel heat sink surface in contact with the heat source body (3) is introduced into the heat. After the working liquid (12) enters the passage space (113), the working liquid (12) can simultaneously pass the porous heat sink (2) on the left and right sides and the flow passage (21) penetrating in the middle to make the working liquid (12) flowing in a plurality of holes (22) of the porous heat sink (2), thereby increasing local convection in the channel space (113), and effectively carrying away the body (1) And a heat source absorbed by the porous heat sink (2), wherein a flow path sandwiched between the two porous heat sinks (2) allows the working fluid (12) to quickly pass through the passage space (113), thereby avoiding The pressure drop caused by the working fluid (12) through the porous heat sink (2) causes a decrease in fluidity.

The microchannel heat sink with a porous heat sink of the present invention and a heat dissipating method thereof are arranged on the heat source body as shown in the fifth step, and the liquid is transported by the flow controller (4) ( 12) circulating in each channel space (113) of the microchannel heat sink, and returning to a water storage unit (41) of the flow controller (4) to complete a cycle step, wherein the channel space (113) The liquid (12) is simultaneously passed through the two porous heat sinks (2) and the flow passage (21) penetrating therethrough, so that the working liquid (12) can flow through the plurality of holes (22) of the porous heat sink (2). Thereby increasing the local convection in the channel space (113), the porous heat sink (2) has good heat conduction effect, and the heat source can be quickly transmitted to the liquid (12), so as to effectively carry away from the seat body (1) and the porous body. The heat source absorbed by the heat sink (2), and providing the flow channel (21) in the middle, to prevent the working liquid (12) from easily increasing the pressure drop only through the porous heat sink (2). The decrease in fluidity leads to problems such as greater output power and increased cost, so that the working fluid (12) can be stably circulated in each of the passage spaces (113) of the porous heat sink (2) to achieve rapid heat dissipation. .

In view of the foregoing description of the embodiments, the operation and the use of the present invention and the effects of the present invention are fully understood, but the above described embodiments are merely preferred embodiments of the present invention, and the invention may not be limited thereto. </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt;

(1) ‧ ‧ ‧ body

(52) ‧‧‧export end (11)‧‧‧microchannel (53)‧‧‧channel space (111)‧‧ ‧ entrance end (54) ‧‧ ‧ heat source (112) ‧ ‧ exit end (113 )‧‧‧Channel space (113A)‧‧‧1st side (113B)‧‧‧Second side (12)‧‧‧Working liquid (2)‧‧‧Porous heat sink (21)‧‧‧ flow path (22) ‧ ‧ holes (3) ‧ ‧ heat source (4) ‧ ‧ flow controller (41) ‧ ‧ water storage unit (5) ‧ ‧ ‧ known heat sink (51) ‧ ‧ entrance end

[First figure] is a partial exploded view of the components of the microchannel heat sink of the present invention. [Second figure] is a schematic view of the components of the microchannel heat sink of the present invention. [Third image] is a schematic diagram of the circulation flow path of the microchannel heat sink of the present invention. [Fourth figure] is a schematic diagram of the working liquid flow of the microchannel heat sink of the present invention. [Fifth] is a flow chart of the method for dissipating heat of the microchannel of the present invention. [Sixth] Schematic diagram of the conventional microchannel heat sink.

Claims (8)

A microchannel heat sink having a porous heat sink, comprising: a body, wherein a plurality of microchannels are provided with an axial length, the microchannels respectively comprise an inlet end, an outlet end and a channel space, The inlet end communicates with the channel space to the outlet end, and the channel space is provided with a first side and a second side; a plurality of porous heat sinks are disposed on the first side and the second side of each channel space, and The porous heat sink forms a first-class track. The microchannel heat sink with a porous heat sink according to claim 1, wherein the plurality of microchannels are disposed at equal intervals in the interior of the body. The microchannel heat sink having a porous heat sink according to the first aspect of the invention, wherein the first side and the second side are inner walls of the microchannel, and the two porous heat sinks are respectively disposed on the The first side and the second side are in conformity with the axial length of the microchannel, and the aforementioned flow path is formed between the two porous heat sinks. The microchannel heat sink with a porous heat sink according to the first aspect of the invention, wherein the porous heat dissipation system is copper, aluminum, tantalum or iron sintered into a long plate block. The microchannel heat sink having a porous heat sink according to the first aspect of the invention, wherein the porous heat sink has a through hole of 0.66 and a permeability of 2.74-10 m ² . A microchannel heat dissipation method with a porous heat sink includes: a microchannel heat sink having a porous heat sink as described in item 1 in a heat source body; and a liquid circulation in the microchannel heat sink Each channel space; in the channel space, the liquid is simultaneously passed through the two porous heat sinks and the two porous heat sinks to form a flow passage therethrough, and the heat source is carried away from the microchannel heat sink. The microchannel heat dissipation method with a porous heat sink according to claim 6, wherein a flow controller is used to transport the liquid to each channel space of the microchannel heat sink. The microchannel heat dissipation method with a porous heat sink according to claim 6, wherein the liquid system is water.