Patent Publication Number: US-2019178582-A1

Title: Cooling plate

Description:
CLAIM OF PRIORITY 
     This application claims priority to Chinese Patent Application 201711297818.4, filed Dec. 8, 2017, the entire contents of which are fully incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure relates to the technical filed of cooling equipment in the vacuum coating filed, and particularly to a cooling plate. 
     BACKGROUND 
     The cooling plate in vacuum coating is usually installed in the processing chamber and wafer-output side of the coating equipment. It can dissipate the heat continuously through the circulating cooling liquid thereof, thereby accelerating the cooling rate of the substrate, effectively reducing the temperature of the substrate when exposed to the atmosphere, and shortening the overall process cycle time of the equipment. 
     The existing cooling plates in the field of vacuum coating mostly adopt a structure directly bent by the single-loop water channels and water pipes machined with deep hole drill in the thick plate. Such structure of the pipes machined with deep hole drill in the thick plate is restricted to the processing technology. Most of them are a single-loop water channel with one inlet and one outlet. The cooling efficiency is low, the temperature difference between the water-inlet side and the water-return side is large, and the temperature uniformity of the entire plate is poor, which seriously affects the overall process cycle time of the equipment; in addition, due to many gaps between each pipe, and the pipes are mostly fixed on the plate when used in a large area, the calandria structure bent by water pipes has a poor heat conduction effect between the pipes and the plate, and needs a lot of maintenance and cleaning work. 
     SUMMARY 
     (I) Technical Problem to be Solved 
     The present disclosure provides a cooling plate, so as to solve the technical problem of the temperature non-uniformity of the cooling plate. 
     (II) Technical Solutions 
     In order to solve the technical problem above, the present disclosure provides a cooling plate, including a cooling plate body and a circulating water channel arranged in the cooling plate body; wherein a water-inlet channel and a water-return channel of the circulating water channel are in parallel. 
     In an embodiment of the present disclosure, the cooling plate body is divided into a plurality of subsections of an integral structure, each subsection is provided with a set of independent circulating water channel. 
     In an embodiment of the present disclosure, each subsection of the cooling plate body is a groove having side walls shared by adjacent subsections, each circulating water channel is arranged in the corresponding groove. 
     In an embodiment of the present disclosure, the circulating water channel comprises water grooves milled on a surface of the groove with parallel water inlet and return, and/or water pipes with parallel water inlet and return. 
     In an embodiment of the present disclosure, bottom plates are further arranged on the cooling plate body; the cooling plate body is divided into four rectangular grooves with two center lines thereof as base lines; each groove is inlaid with a bottom plate sealingly connected with the groove. 
     In an embodiment of the present disclosure, a plurality of bosses are arranged on the cooling plate body at positions staggered to the circulating water channel; accommodating holes corresponding to the bosses are arranged on the bottom plate; the boss is disposed in the accommodating hole and is connected to the bottom plate. 
     In an embodiment of the present disclosure, air distribution pipes are arranged on the bottom plate; penetrated air holes are further arranged on the cooling plate body at positions staggered to the circulating water channel; vent holes corresponding to the air holes are arranged on the bottom plate; air injection holes communicating with the air holes and the vent holes are arranged on the air distribution pipes. 
     In an embodiment of the present disclosure, an air distribution pipe is arranged on a diagonal line of each bottom plate respectively, and air inlet pipes are arranged on each air distribution pipe. 
     In an embodiment of the present disclosure, a main air inlet pipe and a plurality of the air distribution pipes are arranged on the bottom plate, the air distribution pipes communicate with the main air inlet pipe. 
     In an embodiment of the present disclosure, strip bulges are arranged on the circulating water channel in a water flowing direction. 
     In an embodiment of the present disclosure, the cooling plate body is provided with a thermocouple detecting a temperature uniformity of the cooling plate and/or a flow controllable circulating water bump. 
     (III) Advantageous Effects 
     The technical solutions of the present disclosure have the following advantages: by arranging the circulating water channel in which the water-inlet channel and the water-return channel are in parallel in the cooling plate body, the cooling plate provided by the present disclosure solves the problem of the temperature non-uniformity of the entire cooling plate due to the temperature difference of the inlet water and returned water. 
     In addition to the above-mentioned technical problems solved by the present disclosure, the technical features of the technical solutions formed and the merits brought by the technical features of these technical solutions, the other technical features of the present disclosure and the merits brought by these technical features will be further described with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an assembly diagram of the cooling plate according to an embodiment of the present disclosure; 
         FIG. 2  is a plan sketch of the cooling plate according to an embodiment of the present disclosure; 
         FIG. 3  is a sectional view of A-A in  FIG. 2 ; 
         FIG. 4  is an enlarged view of part B in  FIG. 3 ; 
         FIG. 5  is an enlarged view of part C in  FIG. 3 ; 
         FIG. 6  is an enlarged view of part D in  FIG. 3 . 
     
    
    
     In the drawings:  1 : cooling plate body;  11 : boss;  12 : air hole;  2 : bottom plate;  21 : first bottom plate;  22 : second bottom plate;  23 : third bottom plate;  24 : fourth bottom plate;  25 : welding position of the bottom plate and the cooling plate body;  3 : circulating water channel;  31 : comb-shaped structure;  4 : water-inlet pipe;  5 : water-return pipe;  6 : pipe joint;  7 : sleeve joint;  8 : air distribution pipe;  81 : welding position of the air distribution pipe and the bottom plate;  82 : air injection hole;  9 : air inlet pipe;  91 : welding point of the air inlet pipe and the air distribution pipe;  92 : VCR male joint;  93 : VCR male nut. 
     DETAILED DESCRIPTION 
     In order to make the objectives, technical solutions, and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be described clearly with reference to the accompanying drawings hereinafter. Obviously, the described embodiments are merely some but not all of the embodiments of the present disclosure. On the basis of the embodiments of the present disclosure, all other embodiments obtained by the person of ordinary skill in the art without creative work shall fall within the protection scope of the present disclosure. 
     In the description of the present disclosure, it should be noted that unless specifically defined or limited, the terms “mount”, “connect to”, and “connect with” should be understood in a broad sense, for example, they may be fixed connections or may be removable connections, or integrated connections; may be mechanical connections or electrical connections; they may also be direct connections or indirect connections through intermediate medium, or may be internal communication of two components. For a person of ordinary skill in the art, the specific meanings of the terms above in the present disclosure can be understood according to specific situations. 
     In addition, in the description of the present disclosure, unless specified otherwise, “plurality”, means two or more, “a number of”, means one or more. 
     As shown in FIG. 1 , the cooling plate provided by the embodiments of the present disclosure includes a cooling plate body  1 , and a circulating water channel  3  arranged in the cooling plate body  1 ; wherein the circulating water channel  3  is a water channel in which a water-inlet channel and a water-return channel are in parallel. 
     It needs to be noted that, the water-inlet channel and the water-return channel are in parallel means that the water-inlet channel and the water-return channel have a same or similar shape and are adjacent to each other, meanwhile the inlet of the water-inlet channel and the outlet of the water-return channel are at the same end, and the outlet of the water-inlet channel communicates with the inlet of the water-return channel, or the rear end of the water-inlet channel is directly integrated with the front end of the water-return channel. 
     For example, the circulating water channel may be S-shaped. In this case, the water-inlet channel and the water-return channel have a same S-shape, the same ends of the two S-shaped channels are respectively a water inlet and a water outlet, the opposite ends are an integrally intercommunicated structure. It is equivalent to a pipeline completed by two S-shapes, and the two openings are a water inlet and a water outlet respectively. 
     Of course, the shape of the circulating water channel is not limited to the S-shape above, and can be other shapes such as Z-shape or snake-shape. 
     It can be understood that, by arranging the circulating water channel  3  in which the water-inlet channel and the water-return channel are in parallel, in one aspect, the heat exchange area between the cooling plate and the liquid in the circulating water channel  3  is increased, thereby improving the heat exchange efficiency of the cooling plate; in another aspect, by applying the circulating water channel  3  in which the water-inlet channel and the water-return channel are in parallel, the problem of the temperature non-uniformity of the entire cooling plate due to the temperature difference of the inlet water and returned water is solved. 
     Preferably, the circulating water channel in the embodiments of the present disclosure is hollow square. As the first specific embodiment of the present disclosure, the circulating water channel  3  is directly milled on the bottom surface of the cooling plate body  1 , and a bottom plate is welded on the bottom surface of the cooling plate body to seal the circulating water channel, that is, the circulation water channel  3  is formed by fitting the circulating water grooves on the bottom surface of the cooling plate body  1  with the bottom plate. 
     As the second specific embodiment of the present disclosure, the circulating water channel  3  includes water pipes arranged on the bottom plate of the cooling plate body. It needs to be noted that the circulating water channel in the form of water pipes may be directly arranged in the grooves of the first specific embodiment, or may be fixed in other forms. 
     As the third specific embodiment of the present disclosure, the circulating water channel  3  may be a combination of the first specific embodiment and the second specific embodiment, that is, a section of the circulating water channel may be milled grooves, and the other section of the circulating water channel may be in the form of water pipes communicating with the grooves. 
     The fourth specific embodiment of the present disclosure further arranges air holes on the basis of the first specific embodiment, the second specific embodiment or the third specific embodiment. Specifically, a plurality of air holes are provided at the positions on the cooling plate body that stagger to the circulating water channel. It can be understood that, by placing air holes on the cooling plate body, the air can be blown from the bottom to the top when the cooling liquid passes, which effectively dissipates the heat and enhances the heat exchange capacity between the cooling plate and the substrate. 
     Wherein, the air feed equipment for the air holes may be an air distribution pipe disposed under the cooling plate body, and the air injection holes arranged on the air distribution pipe communicate with the air holes. The air feed equipment of the air holes may also be other components, such as a vent plate, etc. 
     As the fifth specific embodiment of the present disclosure, the cooling plate body  1  is divided into a plurality of subsections of an integral structure, and each subsection is provided with a set of independent circulating water channel  3 . It needs to be noted that the specific arrangement of the circulating water channel of the present embodiment may adopt any of the forms of the first specific embodiment, the second specific embodiment or the third specific embodiment, or arrange the air holes of the fourth specific embodiment. 
     It can be understood that the plurality of subsections can shorten the heat exchange time of the circulating liquid in the cooling plate body  1 , so that a large temperature difference between the circulating liquid and the cooling plate of each part can be maintained, thereby improving the heat exchange efficiency, and accordingly shortening the circulation range of each set of circulating water channel, so as to further improve the temperature uniformity of the cooling plate. 
     The cooling plate of the present disclosure will be described in detail hereinafter by taking an example that the cooling plate body is divided into four subsections to cool respectively. 
     As shown in FIG. 1 , the bottom of the cooling plate body of the cooling plate of the present embodiment is divided into four equally divided grooves with two center lines thereof as base lines, wherein adjacent grooves share side walls, and the grooves form rectangles. The four circulating water channels  3  are respectively arranged in four grooves, each of which is inlaid with a bottom plate  2 . For the convenience of description, the bottom plates are defined as a first bottom plate  21 , a second bottom plate  22 , a third bottom plate  23  and a fourth bottom plate  24  respectively. The first bottom plate  21 , the second bottom plate  22 , the third bottom plate  23  and the fourth bottom plate  24  are respectively fully welded with the corresponding grooves. In  FIG. 2 , reference numeral  25  indicates the welding position of the bottom plate and the cooling plate body. 
     On the diagonal lines of the grooves corresponding to the bottom plate  2  and the cooling plate body  1 , a plurality of air holes  12  penetrating the cooling plate body  1  are disposed at the positions staggering to the circulating water channel  3 . The bottom plate  2  is also provided with vent holes (not shown in the drawings) at corresponding positions. Four air distribution pipes  8  corresponding to the diagonal line (that is, in the direction of 45° to the bottom plate  2 ) of each groove respectively are welded on the outer surface of each bottom plate  2 . And each air distribution pipe  8  is provided with air injection holes  82  corresponding to the air holes  12 , and communicating with the air holes  12  and the vent holes.  FIG. 6  is a specific schematic diagram of the air hole  12  and the air injection hole  82 . In  FIG. 2 , reference numeral  81  indicates the welding position of the air distribution pipe and the bottom plate. It can be understood that, by applying the diagonal line, the maximum air injection range can be formed and at the center of the bottom plate  2 , which facilitates the uniformity of the air coming out of the air holes  12 . At the same time, by using the structure that the air distribution pipe  8  is welded to the bottom plate  2 , the air inlet side of the air injection hole can be sealed. 
     Meanwhile, as shown in  FIG. 1 or 2 , each air distribution pipe  8  is connected with an air inlet pipe  9 . Each air inlet pipe  9  extends to the middle position of the cooling plate and is welded to the side of the air distribution pipe  8 , so as to hermetically seal the air inlet pipe and the air distribution pipe. In  FIG. 2 , reference numeral  91  indicates the welding point of the air inlet pipe and the air distribution pipe. A joint is welded at the other end of the air inlet pipe, the joint is preferably to be a VCR male joint  92  on which a VCR male nut  93  is fitted. 
     It can be understood that the air inlet pipe  9  extends to the middle position of the cooling plate, so that the length of the inlet pipe is increased, therefore the inlet pipe is connected with the inlet of the vacuum chamber of air with certain flexibility. That is, the length of the air inlet pipe is increased, so that when it is docked with the inlet of the vacuum chamber, even if the position of the inlet of the vacuum chamber is slightly deviated, the rigid air inlet pipe will not be damaged. 
     Wherein, as shown in  FIG. 2  (only shown in the groove in the lower right corner), the circulating water channel  3  is milled on the surface of the groove. It should be noted that the lower right corner of  FIG. 2  is to show the structure of the circulating water channel, therefore the structure of the bottom plate is removed. 
     It can be understood that, the milled circulating water channel  3  can avoid the water pipe being bent and damaged easily when used for the disk layout. 
     In order to enhance the fixing of the bottom plate  2  with the cooling plate body  1 , as shown in  FIG. 4 , a plurality of bosses  11  are reserved on the cooling plate body  1  at positions staggered to the circulating water channel  3 , and accommodating holes corresponding to the bosses  11  are arranged on the bottom plate. The boss  11  is disposed in the accommodating hole and is connected to the bottom plate by welding. The welding manner is specifically shown in  FIG. 4 . It can be understood that the engagement between the boss  11  and the accommodating hole forms auxiliary welding joints of the bottom plate  2 , and the welding points on the larger surface of the bottom plate  2  are increased, which improves the rigidity of the larger surface of the bottom plate  2 . 
     Preferably, as shown in  FIG. 5 , the bottom surface of the cross section of the circulating water channel  3  is a comb-shaped structure  31 . The comb-shaped structure  31  is a plurality of strip bulges arranged on the circulating water channel  3  and in the flowing direction of the liquid in the circulating water channel  3 . It can be understood that the comb-shaped structure  31  can effectively increase the heat exchange area of the liquid with the cooling plate body  1  when water is flowing, and improve the heat exchange efficiency. 
     The specific processing of the cooling plate of the embodiment of the present disclosure is given below:
     1. cooling plate machining:
       a. machining four grooves on the bottom of the cooling plate (at the inlaying and welding position of the bottom plate), reserving a plurality of bosses  11  on the cooling plate body  1  at positions staggered to the water channels (at the auxiliary welding position with the bottom plate, so as to increase the welding points on the larger surface of the bottom plate, and improve the rigidity of the larger surface of the bottom plate).   b. milling the circulating water channels on the four grooves (as shown in  FIG. 2 ) respectively, wherein each circulating water channel is a two-channel parallel loop, and the water-inlet channel and the water-return channel are in parallel, which facilitates the heat exchange between the higher temperature of returned water (40-60° C.) and the lower temperature of inlet water (16-20° C.), and reduces the effect on the thermal uniformity of the entire plate; the cross section of the water channel is processed into a “comb-shaped structure” (as shown in  FIG. 5 ), which effectively increases the heat exchange area when water is flowing and improves the heat exchange efficiency. The four independent circulating channels increase the flow rate of water that passes through the cooling plate with a unit time, which can effectively improve the cooling efficiency of the cooling plate.   c. machining water-inlet holes and water-return holes at the positions corresponding to the water channel openings on the two sides of the cooling plate, corresponding to the welding positions of the water pipe joints  7 ;   d. as shown in FIG. 2 : forming the air injection holes evenly in the direction of  45  degrees; injecting air can effectively improve the heat exchange efficiency between the cooling plate and the substrate;   
       2. inlaying the first bottom plate, the second bottom plate, the third bottom plate and the fourth bottom plate into the corresponding grooves of the cooling plate, and welding fully to be integrated; performing the leak detection after welding to ensure the sealing, so as to seal the circulating water channels in the cooling plate;   3. welding the air outlets of the four air inlet pipes with the corresponding air distribution pipes respectively, and welding the air inlets of the four air inlet pipes to the VCR male joints respectively;   4. fully welding the air distribution pipes integrated with the air inlet pipes with the first bottom plate, the second bottom plate, the third bottom plate, and the fourth bottom plate respectively, so as to achieve the communication between the main air inlet pipe and each air injection vent on the cooling plate, and forms an air injection pipe passage;   5. welding the pipe joints  6  and the sleeve joints  7  for connecting pipes of the water-inlet pipes  4  and water-return pipes  5  in each subsection.   

     For the plurality of parallel loops of the cooling plate in the embodiments of the present disclosure, the independent circulating water channels are machined in multiple areas of the cooling plate body portion, and the water channels are sealed by welding the bottom plate. Each water-inlet channel and water-return channel of the cooling plate of the embodiments of the present disclosure are parallel, which improves the temperature uniformity of the entire plate due to the temperature difference of inlet water and return water; the cross section of the water channel is a comb-shaped structure, which increases the heat exchange area and improves the heat exchange efficiency; a plurality of areas have independent water circulations, which increases the overall water-flowing capacity of the entire plate, enhances the heat exchange capacity of the cooling plate, and improves the cooling rate of the substrate. Meanwhile, by placing air holes on the cooling plate, the air can be blown from the bottom to the top when the cooling liquid passes, which effectively dissipates the heat and enhances the heat exchange capacity between the cooling plate and the substrate. 
     At the same time, for the cooling plate of the embodiments of the present disclosure, a thermocouple can be arranged on the cooling plate to measure the temperature, so as to detect the uniformity of the cooling plate; in addition to the thermocouple arranged on the cooling plate, a flow controllable circulating water bump also can be supplied to the periphery of the cooling plate, so that an automatic temperature control function of the cooling temperature on the surface of the cooling plate can be achieved. Meanwhile, it is also a feasible solution of the present disclosure that water pipes are arranged in the grooves to form a parallel water inlet and return without sealing the bottom plate. 
     In the embodiments specifically described above, the air inlet thereof is not limited to, as described in the embodiments, that the four air distribution pipes are respectively connected to one air inlet pipe; it may also be achieved by connecting the four air distribution pipes to a main air inlet pipe, that is, one main air inlet pipe communicates with a plurality of air distribution pipes. At the same time, the arrangement of the air distribution pipe is not limited to, as described above, being arranged on the diagonal line; it may also be that a main air inlet pipe is directly placed at the center, and a plurality of air distribution pipes are connected to the two sides of the main air inlet pipe from different positions; for example, air holes are arranged in an approximate “ ” shape at the positions staggered to the circulating water channel, correspondingly, the plurality of air distribution pipes are also connected to the two sides of the main air inlet pipe to form an approximate “ ” shape. 
     In summary, the cooling plate of the embodiments of the present disclosure enhances the cooling effect, improves the efficiency of the cooling plate cooling the substrate, and reduces the effect of the cooling time on the overall process cycle time of the equipment; in addition, the overall temperature uniformity of the cooling plate of the embodiments of the present disclosure is better; and a welded integrated structure is adopted, which facilitates the maintenance at a later stage. 
     Finally, it should be noted that the embodiments above are only used to illustrate rather than to limit the technical solutions of the present disclosure; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or equivalently replace some of the technical features therein; and these modifications or replacements do not separate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of each of the embodiments of the present disclosure.