CN1233038C - Microjet array cooling heat sink - Google Patents

Abstract

The present invention relates to micro-jet array cooling heat sink which belongs to the technical field of microelectronic technology, and the present invention relates to a cooling device. The cooling device comprises an overflowing piece (1), a jet inlet piece (2), a jet nozzle piece (3), a jet outlet piece (4) and a heat transfer piece (5), wherein a liquid inlet and a liquid outlet are arranged on the overflowing piece (1), and a jet inlet, a liquid inlet hole and a liquid outlet hole are arranged on the jet inlet piece (2). A jet nozzle which is communicated with the jet inlet and the jet outlet which is arranged on the jet outlet piece (4), a liquid inlet flow guiding channel which is communicated with the liquid inlet hole and the jet inlet, and a liquid outlet flow guiding channel which is communicated with the liquid outlet hole and the jet outlet are arranged on the jet nozzle piece (3), and the jet outlet is arranged on the jet outlet piece (4). High-heat flux heat transfer is achieved by the cooling device, and the cooling device has high heat transfer speed rate. Temperature on a heat exchange surface of an electronic device is effectively reduced, and the homogeneity of heat exchanger surface temperature can be enhanced.

Description

Microfluidic array cooling heat sink

technical field

The invention belongs to the technical field of microelectronics and relates to a cooling device.

Background technique:

With the continuous development of industrial technology, all kinds of electronic products are developing in the direction of small size, light weight and high heat flux. Therefore, for the new generation of electronic equipment, the design limit and manufacturing technology of the traditional cooler can no longer meet the requirements. The development of micro-coolers stems from solving the heat dissipation problem of high-speed integrated circuits. At present, it has developed into various high heat flux fields with weight restrictions and volume restrictions, such as aerospace industry, cooling of electronic components, cooling of high-power semiconductor lasers, chemical process heat transfer etc. Its main purpose is to reduce the probability of failure and damage of electronic equipment due to overheating, and at the same time improve the performance and reliability of electronic equipment.

At present, micro-coolers that are being actively researched and applied at home and abroad include: micro-heat exchangers, micro-refrigerators, micro-channel heat sinks, micro-heat pipe heat spreaders, and integrated micro-coolers. Among them, the microchannel heat sink has been proved to be one of the cooling methods with the best heat transfer performance and the most application potential.

Two representative microchannel cooling heat sinks generally recognized at present are: traditional microchannel type (Traditional Microchannel Type, TMC) and manifold microchannel type (Manifold Microchannel Type, MMC). The characteristic of TMC heat sink is that the inlet and outlet are respectively located at both ends of the cooled component. Although the TMC heat sink has high cooling capacity, two design limitations limit its wide application. One is the large pressure drop due to the small size; the other is the huge temperature change between the inlet and outlet of the heat source. The MMC heat sink has multiple inlet and outlet channels, which are alternately distributed in the channel length direction at a certain interval. At a fixed flow rate, according to the number of inlets/outlets of the manifold channel, the flow resistance is correspondingly reduced, the range of temperature variation is correspondingly reduced, and the total heat transfer resistance is also correspondingly reduced. Therefore, compared with TMC heat sinks, MMC heat sinks have great advantages. However, whether it is a TMC heat sink or an MMC heat sink, the cooling mechanism is the forced convection heat transfer of the fluid in the channel. The result is that the fluid temperature at the inlet of the channel is low and the cooling effect is good, while the fluid temperature at the outlet is high and the cooling effect is relatively poor, resulting in uneven temperature distribution of the heat exchange surface. The temperature distribution (especially the highest temperature) in this local area is the key to affect the working characteristics of the cooled device, and it is also an important index to evaluate the performance of the microchannel heat sink.

Invention content:

The object of the present invention is to provide a cooling heat sink to overcome the above-mentioned shortcomings of the two microchannel cooling heat sinks.

A kind of cooling heat sink of micro-jet array, it is characterized in that, as shown in Figure 1, comprises flow-through plate 1 that overlaps and packs together successively, jet flows into mouth piece 2, jet nozzle piece 3, jet flows out mouth piece 4, transmission Heat sheet 5; liquid inlet 6 and liquid outlet 7 connected to the external pipeline are opened on the flow sheet 1; injection mouth 8 is provided on the injection mouth sheet 2, and the liquid inlet with the flow sheet 1 The positions corresponding to the mouth 6 and the liquid outlet 7 are respectively provided with a liquid inlet hole 9 and a liquid outlet hole 10, and the jet inlet mouth 8 is not connected with the liquid inlet hole 9 and the liquid outlet hole 10 on the jet inlet mouth piece 2; The mouthpiece 4 is provided with a jet out of the mouth 14 at a position corresponding to the jet into the mouth 8 of the jet into the mouthpiece 2; The jet nozzle 11 composed of an array of holes connected to the outflow mouth 14 communicates with the liquid inlet hole 9 and the liquid inlet guide channel 12 of the jet inflow mouth 8 , and communicates with the liquid outlet hole 10 and the liquid outlet guide channel 13 of the jet outlet mouth 14 .

As shown in Figure 8, on the jet outlet mouthpiece 4 of the present invention, there are liquid inlet holes 9 and liquid outlet holes 10 at positions corresponding to the liquid inlet 6 and the liquid outlet 7 on the flow sheet 1, and the heat transfer A liquid inlet 6 and a liquid outlet 7 are respectively opened on the sheet 5 at positions corresponding to the liquid inlet 6 and the liquid outlet 7 on the flow sheet 1 .

As shown in FIG. 4 , the present invention adopts a jet outlet mouth 14 with microchannels 17 on the jet outlet mouth piece 4 , and the number and positions of the microchannels 17 correspond to the holes in the jet nozzle 11 .

The micro-jet array cooling heat sink proposed by the present invention is based on the theory of jet impingement heat transfer. During jet impingement cooling, the fluid normal impacts the heat transfer surface, forming a very thin velocity and temperature boundary layer, so it has a high heat transfer rate. At the same time, the uniformity of the temperature distribution of the cooled surface can be greatly improved by adopting a reasonable arrangement of micro-jet arrays. Therefore, the micro-fluidic array cooling heat sink is an effective method to reduce the maximum temperature of the heat exchange surface of electronic devices and reduce the temperature change.

As shown in FIG. 2 , the heat sink 15 is cooled by combining and packaging the heat sink to form a micro-fluidic array. A closed fluid circulation can be formed inside the heat sink. The sequence of fluid flow is: liquid inlet 6, liquid inlet hole 9, liquid inlet diversion channel 12, jet inlet mouth 8, jet nozzle 11, jet outlet mouth 14, liquid outlet The guide channel 13 , the liquid outlet 10 , and the liquid outlet 7 , the fluid is sprayed vertically on the heat transfer sheet 5 at a relatively high speed through the jet nozzle 11 , realizing high heat flux and heat transfer.

The heat exchange medium can be air, water, refrigerant and so on. According to the working fluid used and the optimum operating temperature range of the device, a single-phase fluid jet impingement heat exchange and jet impingement phase exchange heat will be formed on the heat transfer surface to meet the cooling technical requirements.

The heat sink can be made of oxygen-free copper, silicon wafer, silver and other materials, and the overall geometric shape and size can be determined according to the size of the cooled device and the overall packaging requirements.

Jet impingement cooling is a strong convective heat transfer method, especially in micro-scale conditions, jet impingement heat transfer has a very high heat transfer rate. The present invention makes full use of the characteristic of extremely high micro-jet impact heat transfer coefficient, and uses the micro-jet array heat sink to cool microelectronic devices. latent heat to achieve higher heat flux.

Description of drawings:

Fig. 1: the structure schematic diagram of jet nozzle with circular hole array of the present invention;

In the figure: 1. flow-through sheet, 2. injection-into-mouth sheet, 3. jet-flow nozzle sheet, 4. jet-outlet-mouth sheet, 5. heat-transfer sheet, 6. liquid inlet, 7. liquid outlet, 8. injection Inflow mouth, 9, liquid inlet hole, 10, liquid outlet hole, 11, jet nozzle, 12, liquid inlet diversion channel, 13, liquid outlet diversion channel, 14, jet flow out of oral cavity;

Fig. 2: the schematic diagram of the present invention having the structure shown in Fig. 1;

In the figure: 15, cooling heat sink;

Fig. 3: the schematic diagram of cooling semiconductor laser bar of the present invention;

In the figure: 16, semiconductor laser bar;

Fig. 4: the structure schematic diagram that has circular hole array jet nozzle and microchannel of the present invention;

In the figure: 17, micro channel;

Fig. 5: the structural representation of jet nozzle with rectangular hole array of the present invention;

Figure 6: a schematic diagram of the present invention having the structure shown in Figure 5;

Fig. 7: the schematic diagram of cooling high-power semiconductor laser array of the present invention;

In the figure: 18, positive pole of power supply, 19, insulating layer, 20, light, 21, inlet pipe, 22, outlet pipe, 23, sealing ring;

Figure 8: Schematic diagram of the structure of the cooling heat sink with liquid inlet and outlet holes on the jet outlet and liquid inlet and outlet on the heat transfer sheet.

Detailed ways

Example 1:

As shown in Figure 3, the semiconductor laser bar 16 is cooled by a micro ^- fluidic array heat sink. The length, width and thickness of a typical semiconductor laser bar 16 are 10000×1000×115 microns, and there are several evenly arranged laser emitters The micro-jet array heat sink 15 is welded sequentially by the flow plate 1, the jet inlet mouth piece 2, the jet nozzle piece 3, the jet outlet mouth piece 4, and the heat transfer piece 5 shown in Fig. 1, and each piece is rectangular , the width is the same as the length of the semiconductor laser bar 16, the semiconductor laser bar 16 is fixed on the heat transfer sheet 5, the jet nozzle 11 is made up of a row of round holes with a diameter of 70 microns, and the depth of the round holes is the thickness of the jet nozzle sheet 3, The number and position of the circular holes correspond to the number and position of the laser emitters in the laser bar. The thickness of the jet outlet mouth piece 4 is 200 microns. The thickness is 300 microns. A closed fluid circulation can be formed inside the heat sink of the micro-jet array, and the sequence of fluid flow is: liquid inlet 6, liquid inlet hole 9, liquid inlet diversion channel 12, jet into the mouth 8, jet nozzle 11, jet out of the mouth 14 , a liquid outlet diversion channel 13 , a liquid outlet hole 10 , and a liquid outlet 7 . The fluid is sprayed vertically on the heat transfer sheet 5 at a high speed through the jet nozzle 11, and takes away the heat generated by the laser emitter and transferred to the heat transfer sheet 5, thereby realizing high heat flux heat transfer.

Example 2:

As shown in Figure 4, the jet outlet mouth 14 on the jet outlet mouth piece 4 has a microchannel 17, the quantity and position of the microchannel 17 are corresponding to the round hole in the jet nozzle 11, and the width of the microchannel 17 is 300- 500 microns. After the processing of each piece is completed, they are welded together in turn to form a micro-jet cooling heat sink. The flow sequence of the fluid inside the heat sink is: liquid inlet 6, liquid inlet hole 9, liquid inlet diversion channel 12, jet flow Mouth 8, jet nozzle 11, microchannel 17, jet exit mouth 14, liquid outlet guide channel 13, liquid outlet 10, liquid outlet 7; High speed, vertical spraying on the heat transfer sheet 5 realizes high heat flux heat transfer, and then the fluid flows through the microchannel 17 to the jet outlet cavity 14, realizing heat exchange with the heat transfer surface, making full use of the jet impact heat transfer Cooling method combined with forced convection heat transfer in the channel.

Example 3:

As shown in Figure 5, two jet nozzle sheets 3 with a thickness of 200 microns are used, and the jet nozzle 11 is composed of a row of evenly arranged rectangular holes with a width of 40 microns and a length of 500 microns. is 200 microns, and the thickness of the flow plate 1, the injection cavity plate 2, and the heat transfer plate 5 are all 300 microns, as shown in FIG. 6 is a schematic diagram of the heat sink with the structure in FIG. 5. The flow sequence of the fluid inside the heat sink is: liquid inlet 6, liquid inlet hole 9, liquid inlet diversion channel 12, jet inlet mouth 8, jet nozzle 11, jet outlet mouth 14, liquid outlet diversion channel 13, liquid outlet Hole 10, liquid outlet 7. The fluid is sprayed vertically and at high speed on the heat transfer sheet 5 through the rectangular hole of the jet nozzle 11 in a plane jet manner, so as to realize the cooling of some devices with long and narrow heat-generating regions.

Example 4:

As shown in Figure 7, adopt cooling high-power semiconductor laser array of the present invention, this array is made up of M light-emitting units, in the present embodiment M=4, is coated with insulating layer 19 between each light-emitting unit; Each light-emitting unit comprises 1. Power supply positive pole 18, cooling heat sink 15, and semiconductor laser bar 16 and insulating layer 19 placed between them, cooling heat sink 15 as power supply negative pole simultaneously, semiconductor laser bar 16 emits light 20 under the effect of electric field. The fluid enters each cooling heat sink 15 through the inlet pipe 21 and flows out through the outlet pipe 22; there is a rubber sealing ring 23 between the inlet pipe 21, the outlet pipe 22 and the cooling heat sink 15 for sealing.

In this embodiment, the uppermost cooling heat sink 15 has the same structure as that shown in Figure 1, that is, there are no liquid inlet and outlet holes on the jet outlet sheet 4 and the heat transfer sheet 5, and the jet flow of the lower cooling heat sink 15 exits the oral cavity. Sheet 4 and heat transfer sheet 5 are respectively processed with inlet and outlet holes and inlet and outlet ports, as shown in Figure 8, so that the cooling fluid can enter each heat sink through the same inlet pipe, and pass through the same outlet The flow out of the tube realizes the cooling of the high-power semiconductor laser array.

Claims (3)

1, a kind of micro-jet array cooling heat sink, it is characterized in that, comprise the flow-through plate (1) that overlaps and packs together successively, injection mouth piece (2), jet nozzle piece (3), jet outlet piece (4) ), the heat transfer fin (5); the liquid inlet (6) and the liquid outlet (7) connected to the external pipeline are opened on the overflow sheet (1); the jet inlet (2) is provided with a jet inlet The mouth (8) has a liquid inlet (9) and a liquid outlet (10) at the positions corresponding to the liquid inlet (6) and the liquid outlet (7) on the flow plate (1), and the jet flows into The oral cavity (8) and the liquid inlet hole (9) and the liquid outlet hole (10) are not connected to each other on the injection mouth piece (2); The position corresponding to the mouth (8) is provided with a jet outlet mouth (14); the jet nozzle sheet (3) is provided with a jet outlet mouth (8) and a jet outlet mouth (14) arranged on the jet outlet mouth piece (4). ) connected to the jet nozzle (11) composed of hole arrays, connected to the liquid inlet hole (9) and the liquid inlet diversion channel (12) of the jet inflow mouth (8), connected to the liquid outlet hole (10) and the jet outlet mouth ( 14) out of the liquid guide channel (13). 2. A cooling heat sink for a micro-fluidic array according to claim 1, characterized in that, the liquid inlet (6) and outlet of the jet outlet piece (4) on the flow piece (1) A liquid inlet (9) and a liquid outlet (10) are respectively opened at positions corresponding to the liquid port (7); ) and the positions corresponding to the liquid outlet (7) respectively have a liquid inlet hole (6) and a liquid outlet hole (7). 3. A micro-fluidic array cooling heat sink according to claim 1, characterized in that, the jet outlet cavity (14) with a microchannel (17) is adopted on the jet outlet cavity sheet (4), and the microchannel The number and position of (17) correspond to the holes in the jet nozzle (11).

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