TWI819157B - Ultra-thin vapor chamber and manufacturing method thereof - Google Patents

Abstract

The invention relates to an ultra-thin vapor chamber and a manufacturing method thereof. The manufacturing method includes selecting metal powder with good thermal conductivity, mixing the metal powder with good thermal conductivity with a solvent suitable for screen printing, and printing the mixture with screen printing. Form a support part with a predetermined height, area, and shape on a thin first metal plate with good thermal conductivity, and sinter the first metal plate in the aforementioned process to form a porous structure and combine the support part with the first metal plate. The first metal plate and the thin second metal plate with good thermal conductivity are welded and sealed, and then vacuumed and injected with working fluid to form an ultra-thin vapor chamber. The aforementioned metal powder with good thermal conductivity is copper powder. The first metal plate and the second metal plate are The plate system is sealed by diffusion welding.

Description

Ultra-thin vapor chamber and manufacturing method thereof

The invention belongs to the technical field of uniform temperature dissipation. In particular, it refers to a new design of an ultra-thin uniform temperature plate and its manufacturing method, which has an environmentally friendly process and high-efficiency temperature uniformity effect.

According to conventional electronic components, most of them use metal heat sinks or a combination of heat pipes, cooling chips, cooling fans, etc., which generally have shortcomings such as poor heat dissipation effect, insufficient heat dissipation speed, complex heat dissipation module structure, and high cost. .

The heat pipe technology was born as early as 1963 at the Los Alamos National Laboratory in the United States. Its inventor is G.M. Grover. The heat pipe is a heat transfer element that makes full use of the principle of heat conduction and the rapid heat transfer properties of the refrigerant medium. Through the heat pipe, the heat of the heating object is quickly transferred to the outside of the heat source. Its thermal conductivity far exceeds the thermal conductivity of any known metal. . In the past, heat pipe technology has been widely used in aerospace, military and other industries, but it was only introduced into the radiator manufacturing industry in recent years. Why does heat pipe technology have such high performance? We have to look at this issue from the perspective of thermodynamics. The heat absorption and heat release of objects are relative. Whenever there is a temperature difference, heat will inevitably transfer from a high temperature place to a low temperature place. There are three ways of heat transfer: radiation, convection, and conduction, among which heat conduction is the fastest. The heat pipe uses evaporative refrigeration to make the temperature difference between the two ends of the heat pipe very small, allowing the heat to be transferred quickly. Common heat pipes are composed of a tube shell, a liquid-absorbing wick and an end cap. The production method is to pump the inside of the heat pipe to a negative pressure state, and then fill it with an appropriate liquid. This liquid has a very low boiling point and is easy to volatilize. The tube wall has a liquid-absorbent wick, which is made of capillary porous material. hot One end of the tube is the evaporation end, and the other end is the condensation end. When one section of the heat pipe is heated, the liquid in the capillary tube evaporates rapidly. The vapor flows to the other end under a slight pressure difference, releases heat, and condenses back into liquid. The liquid then flows back to the evaporation section along the porous material by capillary force, and the cycle continues. Heat is transferred from one end of the heat pipe to the other end. This cycle is rapid and the heat can be conducted continuously. However, the current fin-type radiator is not very efficient in heat conduction and cannot absorb a large amount of heat instantly. How to combine heat pipes and fin-type radiators to improve heat dissipation efficiency is the invention of the vapor chamber. For example, my country's patent M255446 flat plate heat expansion plate (refer to the patent announcement information on January 11, 2005) mainly includes a pair of shells with good thermal conductivity. The pair of shells has an opening on one side and an appropriate number of pillars inside. An air flow channel is formed. A layer of porous powder layer with good thermal conductivity is sintered on the inner edge of the casing and sealed by a cover to form a plurality of staggered tubular channels inside the casing. After the working fluid is injected and the vacuum is evacuated, the The metal powder layer adsorbs the working fluid to form a flat heat expansion plate. However, the conventional vapor chamber is either made of powder with good thermal conductivity sintered inside the second shell or metal mesh with good thermal conductivity. Although they all have the effect of heat expansion and temperature equalization, they are currently used in electronics in 4G computer rooms. Components may generate high heat in an instant due to large flow rates. The structure of the conventional vapor chamber is not fast enough for heat diffusion and temperature equalization, which may cause overheating, crash or damage to electronic components. The applicant previously applied for a temperature equalizing element (Announcement No. M494289), which mainly includes a pair of metal shells with good thermal conductivity. The pair of shells has a working space inside, and there are an appropriate number of thermal conductive columns in the working space to connect the pair. The shell, by sealing the pair of shells, forms a plurality of staggered channels inside the shell, and then evacuates and injects an appropriate amount of working fluid to form a vapor chamber. The characteristic is: the thermal conductive column is made of powder with good thermal conductivity. The porous structure uses the thermal conductive pillars of the porous structure to absorb the working fluid, which has a better capillary phenomenon during operation, can indeed accelerate the diffusion of temperature, and has a more efficient temperature equalization effect.

Furthermore, heat pipe products (including vapor chambers) transfer heat through the liquid-vapor phase change and flow of the internal working fluid, and their heat conduction and diffusion capabilities are superior to all currently known materials of the same size. If heat pipe products can be introduced into current thin and light mobile device products, and their temperature equalization characteristics can be used to quickly diffuse the waste heat generated by high-heating chips from the direction of the heat pipe, the system operation will be more stable. However, in heat dissipation modules for thin and light mobile device products, most commonly used heat pipes have a diameter of 6mm or 8mm, which is even thicker than that of mobile devices. In addition, the thickness of traditional equalization plates is also more than 2~3mm, so it cannot be directly used in mobile devices. As for the device, it must be made thinner before it can be introduced into a mobile device with limited space. In view of the heat dissipation needs of mobile devices, many heat pipe manufacturers have continuously invested in the development of thin heat pipes or vapor chamber products in recent years as the future direction of industry development, and have released ultra-thin heat pipes or vapor chambers with a thickness of less than 1mm. Heat pipes and vapor chambers operate on much the same principles, so their design principles are almost the same. However, compared with the thin heat pipe, the width is limited and can only be changed in one-dimensional length direction. The advantage of a thin vapor chamber is that its area can be changed according to needs, so the degree of change in design is very high, and it can be regarded as a two-dimensional temperature equalizing body. For example, the Industrial Research Institute developed a silicon-based thin vapor chamber using a micro-electromechanical process. It uses a silicon wafer as a substrate to etch micron-level capillary structures. There are also other companies that use etching processes to prepare traditional metal vapor chambers. However, due to the etching process, The etching solution used is very unenvironmentally friendly. This is a drawback. How to use other environmentally friendly processes to thin the vapor chamber has become a problem that the industry needs to overcome urgently.

In view of the deficiencies in the conventional technology mentioned above, the inventor of the present invention has accumulated professional knowledge in the design and manufacturing of precision ceramic technology industrial products for many years. After continuous research and improvement, he finally successfully developed the present invention and made it public to the world.

The reason is that the main purpose of the present invention is to provide a method for manufacturing an ultra-thin vapor chamber The manufacturing method is to select metal powder with good thermal conductivity (coarser particles are better), mix the metal powder with good thermal conductivity and a solvent suitable for screen printing, and print the aforementioned mixture on a thin surface with good thermal conductivity by screen printing. A support portion with a predetermined height, area, and shape is formed on a metal plate. The first metal plate is sintered through the aforementioned process, so that the support portion forms a porous structure and is combined with the first metal plate. The first metal plate sintered through the aforementioned process is combined with the first metal plate. The thin second metal plate with good thermal conductivity is welded and sealed, and then vacuumed and injected with working fluid to form an ultra-thin vapor chamber.

In the present invention, the inner end surface of the second metal plate is first sintered with a porous structural layer using metal powder with good thermal conductivity, and then welded and sealed with the first metal plate to increase the heat expansion and temperature equalization efficiency.

The aforementioned metal powder with good thermal conductivity in the present invention is copper powder.

According to the present invention, the first metal plate and the second metal plate are sealed by diffusion welding.

Another main object of the present invention is to provide an ultra-thin vapor chamber, which mainly includes a thin first metal plate and a second metal plate with good thermal conductivity. There is a working space between the first metal plate and the second metal plate. The inner edge of the metal plate has a support portion with a predetermined height, area, and shape formed by screen printing. The support portion is made of metal powder with good thermal conductivity sintered into a porous structure. The aforementioned support portion is used when sealing the first metal plate and the second metal plate. Welded to the opposite inner edge of the second metal plate, the first metal plate and the second metal plate are sealed to form a plurality of staggered channels in the internal working spaces of the first metal plate and the second metal plate, and then vacuumed and injected with an appropriate amount of work fluid to form an ultra-thin vapor chamber. Since the support part is made of powder sintered with good thermal conductivity to form a porous structure, the porous structure support part absorbs the working fluid and has better capillary phenomenon during operation to accelerate the temperature change. Diffusion, with more efficient temperature equalization effect.

The inner end surface of the second metal plate of the present invention has a metal powder sintered with good thermal conductivity. The porous structural layer is formed to increase the heat expansion and temperature equalization efficiency.

The aforementioned metal powder with good thermal conductivity in the present invention is copper powder.

(1)‧‧‧Ultra-thin vapor chamber

(2)‧‧‧The 1st metal plate

(3)‧‧‧Second metal plate

(30)‧‧‧Porous structural layer

(4)‧‧‧Work space

(40)‧‧‧Channel

(5)‧‧‧Support part

Figure 1 is a top view of an embodiment of the present invention;

Figure 2 is a partial assembly sectional view of an embodiment of the present invention;

Figure 3 is a partially assembled cross-sectional view of another embodiment of the present invention.

In order to achieve the above-mentioned object of the present invention, the technical means are enumerated and described below together with the drawings, so that the review committee can gain a better understanding of the method, structure, characteristics and achieved effects of the present invention.

The ultra-thin vapor chamber of the present invention usually refers to those with a thickness of less than 1 mm, and also has flexibility (bending), which is called a soft vapor chamber, and can be applied to thin and light mobile devices such as mobile phones.

The manufacturing method of ultra-thin vapor chamber of the present invention is as follows:

Choose metal powder with good thermal conductivity (coarser particles are better);

Mix the aforementioned metal powder with good thermal conductivity and a solvent suitable for screen printing;

The aforementioned mixture is printed on a thin first metal plate with good thermal conductivity by screen printing to form a support portion with a predetermined height, area, and shape (as shown in Figure 1, the shape and area of the support portion, the shape and area of the support portion etc., which are designed in conjunction with the temperature equalization components to be bonded);

The first metal plate is sintered in the aforementioned process, so that the support part forms a porous structure and is combined with the first metal plate, and the screen printing is mixed with the solvent and burned off. The porous structure support part absorbs the working fluid and has better performance during operation. Capillary phenomenon to accelerate the diffusion of temperature and have more efficient In addition, the support part can prevent the surface of the first metal plate and the second metal plate from being dented during subsequent vacuuming and degassing operations inside the vapor chamber, and prevent the vapor chamber from interfacing with the surface of the electronic heating element. During contact, due to the aforementioned dent problem, smooth surface-to-surface contact cannot be achieved, which in turn affects the thermal conductivity efficiency;

Welding and sealing the first metal plate sintered by the aforementioned process and the thin second metal plate with good thermal conductivity;

After vacuuming and injecting working fluid, an ultra-thin vapor chamber is made.

In the present invention, the inner end surface of the second metal plate is first sintered with a porous structural layer using metal powder with good thermal conductivity, and then welded and sealed with the first metal plate to increase the heat expansion and temperature equalization efficiency.

The aforementioned metal powder with good thermal conductivity in the present invention is copper powder.

According to the present invention, the first metal plate and the second metal plate are sealed by diffusion welding. Diffusion Bonding Technology is a solid-state joining technology that uses high temperature and pressure in a vacuum environment to make the distance between the contact surfaces of two workpieces reach the atomic distance, allowing atoms to embed and diffuse into each other to join metals and or ceramics. part. Compared with traditional welding technology, diffusion welding can make the joint surface stronger and reduce deformation.

Please refer to the top view of the embodiment of the present invention in Figure 1 and the partial assembly cross-sectional view of the embodiment of the present invention in Figure 2. It can be seen from the figure that the ultra-thin vapor chamber (1) of the present invention mainly includes a thin and excellent thermal conductivity. A metal plate (2) and a second metal plate (3). There is a working space (4) between the first metal plate (2) and the second metal plate (3). The inner edge of the first metal plate (2) has a mesh The support part (5) is formed by plate printing with a predetermined height, area, and shape. [As shown in the embodiment in Figure 1, the shape and area of the support part (5) are determined according to the shape and area to be pasted. Designed with uniform temperature components], the support part (5) is made of metal powder with good thermal conductivity sintered into a porous structure. The aforementioned support part (5) seals the first metal plate (2) and the second metal The plate (3) is welded to the opposite inner edge of the second metal plate (3), and by sealing the first metal plate (2) and the second metal plate (3), the first metal plate (2) and the second metal plate (3) The internal working space (4) forms a plurality of staggered channels (40), which are then evacuated and injected with an appropriate amount of working fluid to form an ultra-thin vapor chamber (1). Since the support part (5) is thermally conductive The better powder is sintered to form a porous structure, and the porous structure support part (5) absorbs the working fluid, which has better capillary phenomenon during operation, can indeed accelerate the diffusion of temperature, and has a more efficient temperature equalization effect. In addition, the The support part (5) can prevent the surface of the first metal plate (2) and the second metal plate (3) from being dented due to the subsequent vacuuming and degassing operation inside the vapor chamber, and prevent the vapor chamber from interfacing with the electronic heating element. When the surfaces are in contact, it is impossible to achieve smooth surface-to-surface contact due to the aforementioned dent problem, which in turn affects the thermal conductivity efficiency.

Please refer to Figure 3. The inner end surface of the second metal plate (3) of the present invention has a porous structural layer (30) made of sintered metal powder (such as copper powder) with good thermal conductivity to increase the heat expansion and temperature equalization efficiency.

The aforementioned metal powder with good thermal conductivity in the present invention is copper powder.

To sum up, the "ultra-thin vapor chamber and its manufacturing method" disclosed in the present invention is unprecedented and has not been seen in published publications at home and abroad. It is considered to have novelty patent requirements, and the present invention It is clear that the deficiencies in conventional technology can be eliminated and the design purpose has been achieved. It has also fully met the patent requirements. I have submitted the application in accordance with the law. I sincerely ask your review committee to review it favorably and grant the patent to this case. I think it will be very convenient.

However, the above is only one of the best possible embodiments of the present invention and is not intended to limit the scope of the present invention. Anyone familiar with the art can use the description of the present invention and the patent application scope to make alternative methods or Equivalent structural changes should be included in the patent scope of the present invention.

(1)‧‧‧Ultra-thin vapor chamber

(2)‧‧‧The 1st metal plate

(3)‧‧‧Second metal plate

(4)‧‧‧Work space

(40)‧‧‧Channel

(5)‧‧‧Support part

Claims (4)

A method for manufacturing an ultra-thin vapor chamber. The ultra-thin vapor chamber has a thickness of less than 1 mm and is a flexible soft vapor chamber. The manufacturing method is as follows: selecting a thin first metal plate with good thermal conductivity; A second metal plate with good thermal conductivity; select metal powder with good thermal conductivity; mix the aforementioned metal powder with good thermal conductivity with a solvent suitable for screen printing; print the aforementioned mixture on the thin first metal plate with good thermal conductivity by screen printing to form a predetermined The height, area, and shape of the support part; sintering the first metal plate through the aforementioned process, so that the support part forms a porous structure and is combined with the first metal plate; the inner end surface of the thin second metal plate with good thermal conductivity is first used for thermal conductivity The best metal powder is sintered into a porous structure layer; the first metal plate and the second metal plate sintered in the aforementioned process are welded and sealed by diffusion welding; and then the ultra-thin uniform is made by vacuuming and injecting working fluid. Warm plate. In the method for manufacturing an ultra-thin vapor chamber described in item 1 of the patent application, the metal powder with good thermal conductivity is copper powder. An ultra-thin vapor chamber. The ultra-thin vapor chamber has a thickness of less than 1 mm and is a flexible soft vapor chamber. It mainly includes a thin first metal plate and a second metal plate with good thermal conductivity. The third metal plate has a thickness of less than 1 mm and is flexible. There is a working space between a metal plate and the second metal plate. The inner edge of the first metal plate has a support part with a predetermined height, area, and shape formed by screen printing. The support part is made of metal powder with good thermal conductivity sintered into a porous structure. , the aforementioned support portion is welded to the opposite inner edge of the second metal plate when sealing the first metal plate and the second metal plate, and the inner end surface of the aforementioned second metal plate is made of metal with good thermal conductivity. The porous structure layer formed by powder sintering seals the first metal plate and the second metal plate so that the working space inside the first metal plate and the second metal plate forms a plurality of staggered channels, and then is evacuated and An appropriate amount of working fluid is injected to form an ultra-thin vapor chamber. The supporting part of the porous structure absorbs the working fluid and supports, which has a better capillary phenomenon during operation to accelerate the diffusion of temperature and achieve high efficiency. Temperature equalization effect. For example, in the ultra-thin vapor chamber described in item 3 of the patent application, the metal powder with good thermal conductivity is copper powder.

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