Patent Application
20250066926
This application claims priority to Chinese Patent Application No. 202211111691.3, titled “LIQUID METAL SUBSTRATE CLEANING METHOD AND CLEANING AND COATING INTEGRATED DEVICE”, filed on Sep. 13, 2022, which are incorporated herein by reference in their entirety.
The present disclosure herein relates to the technical field of thermal interface materials construction, in particular to a liquid metal substrate cleaning method and cleaning and coating integrated device.
Compared with the traditional silicone grease, liquid metal is difficult to be coated on the surface of the chip and the radiator because of the large surface tension. Poor coating will seriously affect the heat dissipation performance of the chip and cause product defects. At present, there are mainly two ways: first, the liquid metal is modified to increase the viscosity of the liquid metal at the expense of some thermal conductivity, which can reduce the difficulty of coating the liquid metal on the substrate to some extent; secondly, solving the coating problem of liquid metal by repeatedly brushing for dozens of times. The principle is similar to that of modification treatment, which also sacrifices part of thermal conductivity and shortens the service life of liquid metal. Neither of the two methods can solve the wetting problem between liquid metal and substrate well. Therefore, it is necessary to find a method that can solve the wetting problem between liquid metal and substrate without reducing the performance of liquid metal, and at the same time ensure the convenience of manufacturing and mass production.
Because liquid metal is a new industry, there is no integrated device suitable for liquid metal substrate cleaning and liquid metal coating in the current market. The traditional solution is to use multiple single-function devices together, which is not conducive to the promotion and application of the industry.
The information disclosed in this background is only intended to increase the understanding of the general background of the present disclosure, and should not be taken as an admission or any form of suggestion that this information constitutes the prior art that is known to those skilled in the art.
In order to solve the technical problems in the prior art that liquid metal coating is difficult and the thermal conductivity of liquid metal is sacrificed, a liquid metal substrate cleaning method and cleaning and coating integrated device are provided.
The present disclosure is mainly realized by cleaning the chip and radiator, Although the chip and radiator are relatively clean to human eyes, there is actually a thin layer of stains on their surfaces, which mainly contain organic matter and inorganic matter. As long as these two kinds of substances are cleaned, liquid metal has good wettability to the chip and radiator in theory.
In the first aspect of the present disclosure, a cleaning method for a liquid metal substrate is provided, comprising a substrate cleaning and a cleaning qualification inspection, and the steps are as follows:
In some embodiments, the inorganic cleaning reagent is selected from one of a sodium bicarbonate solution, a low-concentration strong acid solution, a high-concentration weak acid solution, a low-concentration strong alkali solution and a high-concentration weak alkali solution.
In some embodiments, the strong acid solution is selected from one or more of dilute hydrochloric acid, dilute sulfuric acid, dilute nitric acid, hydrobromic acid, hydroiodic acid, phosphoric acid and permanganic acid;
In some embodiments, the organic reagent is selected from one or more of alcohols, hydrocarbons, ethers, esters and ketones.
In some embodiments, the organic reagent is selected from one or more of ethanol, methanol, dipropylene glycol butyl ether, diethylene glycol butyl ether, hydrocarbon, acetone, toluene, ethyl acetate and ethyl ether.
In some embodiments, the substrate cleaning includes the following method steps:
The above cleaning methods are one or a combination of cleaning methods, and the above methods can be selected according to actual needs.
In some embodiments, the inorganic cleaning reagent is sodium bicarbonate solution, and the organic reagent is anhydrous ethanol.
In the second aspect of the present disclosure, a liquid metal substrate cleaning and coating integrated device is provided, comprising an integration platform, a cleaning unit, an erasing unit, a coating unit and an image sensor are installed on the integration platform, and the integration platform is installed on a moving mechanism. The functions of cleaning, erasing and coating are integrated into one device, and the image information is captured by the image sensor and transmitted to the control system, to realize the movement and positioning of the device. Then, the substrate is repeatedly cleaned and erased according to the program, so that the oil stains on the surface of the substrate are thoroughly cleaned, and the cleaned substrate is directly coated, eliminating the intermediate transfer step and avoiding secondary pollution.
In some embodiments, the cleaning unit includes a plurality of cleaning devices, the erasing unit is provided with at least one erasing device, and the coating unit is provided with at least one coating device. Preferably, the cleaning device comprises a plasma cleaning machine, a first wiping head and a second wiping head, wherein the first wiping head is filled with the above-mentioned inorganic reagent, and the second wiping head is filled with the above-mentioned organic reagent.
The above-mentioned working method of the integrated device comprises the following steps:
In some embodiments, the working units of the cleaning device, the erasing device and the coating device are all exposed outside the integration platform, and face vertically downwards. The plug-in design is compatible with the installation of most traditional production lines.
In some embodiments, the cleaning device and the coating device are respectively provided with accommodating cavities for holding cleaning liquid and liquid metal.
In some embodiments, the cleaning device comprises the plasma cleaning machine, the first wiping head and the second wiping head, wherein the first wiping head is filled with sodium bicarbonate solution, and the second wiping head is filled with anhydrous ethanol.
In some embodiments, the moving mechanism comprises an X-direction sliding table and a Z-direction sliding table, and the integration platform can move left or right relative to the X-direction sliding table, and can move up or down relative to the Z-direction sliding table, respectively.
In some embodiments, the moving mechanism further comprises a Y-direction sliding table, and the integration platform can move back or forth relative to the Y-direction sliding table. The movement of the integrated platform in three-dimensional space is realized by setting the X-direction sliding table, the Z-direction sliding table and the Y-direction sliding table.
In some embodiments, the integrated device further comprises a first supporting frame and a second supporting frame, wherein the first supporting frame is fixedly connected with one end of the X-direction sliding table, and the second supporting frame is fixedly connected with the other end of the X-direction sliding table.
In some embodiments, the bottom of the first supporting frame and the second supporting frame are respectively provided with connectors. The first supporting frame and the second supporting frame are fixed to the production line platform via the connectors.
Compared with the prior art, the present disclosure has the following technical effects:
In the figures:
In the following, the technical scheme of the present disclosure will be explained through specific embodiments with the accompanying drawings. It should be understood that one or more steps mentioned in the present disclosure do not exclude the existence of other methods and steps before and after the combination step, or other methods and steps can be inserted between these explicitly mentioned steps. It should also be understood that these examples are only used to illustrate the present disclosure and are not used to limit the scope of the present disclosure. Unless otherwise specified, the numbering of each method step is only for the purpose of identifying each method step, and does not limit the arrangement order of each method or limit the scope of implementation of the present disclosure. The change or adjustment of its relative relationship can also be regarded as the scope of implementation of the present disclosure without changing the substantive technical content.
The raw materials and instruments used in the embodiments have no specific restrictions on their sources, and can be purchased in the market or prepared by conventional methods familiar to those skilled in the art.
As shown in
The cleaning unit comprises a plasma cleaning machine 21, a first wiping head 22 and a second wiping head 23, wherein the first wiping head 22 is a sodium bicarbonate solution wiping head and the second wiping head 23 is an anhydrous alcohol wiping head; the erasing unit 3 is provided with an erasing device; and the coating unit 4 is provided with a coating device; each device is arranged in turn in the transverse direction, and the working units of each device are exposed outside the integration platform 1, perpendicular to a substrate sample 10; and each cleaning device is respectively provided with an accommodating cavity for holding a cleaning reagent, and the coating device is provided with an accommodating cavity for holding liquid metal.
The moving mechanism 6 comprises an X-direction sliding table 61 and a Z-direction sliding table 62, and the integration platform 1 can move left or right relative to the X-direction sliding table 61, and can move up or down relative to the Z-direction sliding table 62, respectively, and also comprises a Y-direction sliding table 63, and the integration platform 1 can move back and forth relative to the Y-direction sliding table 63.
The moving mechanism 6 is any device in the prior art that can realize two-dimensional or three-dimensional space movement. In this embodiment, the integration platform 1 is fixedly connected with a fixing piece, and the fixing piece is slid and installed on the Z-direction sliding table 62; two ends of the X-direction sliding table 61 are respectively fixed on a first supporting frame 71 and a second supporting frame 72. Specifically, a first groove 711 is arranged on the first supporting frame 71, a second groove 721 is arranged on the second supporting frame, one end of the X-direction sliding table 61 is installed on the first groove 711, and the other end is installed on the second groove 721. The Z-direction sliding table 62 is slid and installed on the X-direction sliding table 61, and the Z-direction sliding table 62 can drive the integration platform 1 and its devices to move left or right along the X-direction sliding table; and in order to increase the function of forward or backward movement of the integration platform 1, both ends of the X-direction sliding table 61 slide the Y-direction sliding table 62 respectively, thus realizing the forward or backward movement of the integration platform 1 along the Y-axis direction.
The bottom of the first supporting frame 71 and the second supporting frame 72 are respectively provided with connectors 8, which are integrated devices and fixed on both sides of the production line platform 9.
In this embodiment, each cleaning device, erasing device, coating device and image sensor 5 are connected with the Programmable Logic Controller (PLC) control system, and automation is realized through PLC control.
The working process of the liquid metal substrate cleaning and coating integrated device is as follows:
After the cleaning step is completed, the cleaning is detected qualified or not based on the diffusion area of the organic reagent, and the larger the diffusion area, the cleaner the substrate is. Specifically, the computer controls the anhydrous ethanol wiping head to drop a drop of anhydrous ethanol on the work piece, and then controls the image sensor 5 to collect images and upload the images to the computer, and the computer calculates that the maximum area of anhydrous ethanol after diffusion is not less than 6.5 times of the area just dropped, and if it is less than the set value, it will enter the cleaning step again, and if it is greater than or equal to the set value, it will enter the next step;
The computer controls the liquid metal coating device to coat the work piece with liquid metal.
Comparative experiment:
Comparing
Obviously, the problem that liquid metal and the substrate are not wetted can be fundamentally solved by repeatedly cleaning nickel-plated copper blocks using the integrated device of the present disclosure.
The sodium bicarbonate solution used in the present disclosure can be replaced by aqueous solutions of dilute hydrochloric acid, dilute sulfuric acid, dilute nitric acid, hydrobromic acid, hydroiodic acid, phosphoric acid, permanganic acid, carbonic acid, acetic acid, hydrofluoric acid, sodium hydroxide, potassium hydroxide, barium hydroxide and sodium carbonate;
The foregoing description of specific exemplary embodiments of the present disclosure is for the purpose of explanation and illustration. These descriptions are not intended to limit the present disclosure to the precise form disclosed, and obviously, many changes and variations may be made in accordance with the above teachings. The purpose of selecting and describing exemplary embodiments is to explain the particular principle of the present disclosure and its practical application, so as to enable those skilled in the art to realize and utilize various exemplary embodiments and various choices and changes of the present disclosure. The scope of the present disclosure is intended to be defined by the claims and their equivalents.
In the description of the present disclosure, it should be understood that the terms “center”, “vertical”, “horizontal”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc. indicate that the orientation or position relationship is based on the orientation or position relationship shown in the accompanying drawings, and is only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, therefore it cannot be understood as limitations to the present disclosure.
In addition, the terms “first”, “second” and so on are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. In the description of the present disclosure, “a plurality of” means more than two, unless otherwise specifically defined.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202211111691.3 | Sep 2022 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2023/070416 | 1/4/2023 | WO |
