Coating system and coating method

Abstract

The application discloses a coating system and a coating method, and belongs to the technical field of coating. The coating system comprises a reaction cavity and a gas inlet device. The gas inlet device is provided with two branch distribution pipes. A plurality of cavity gas inlet pipes are arranged on the two pipes and correspondingly distributed along the height direction of the cavity. The gas flow directions in the two pipes are opposite. The pipe diameters of the cavity gas inlet pipes on each branch distribution pipe gradually increase along the gas flow direction. The pipe diameter sequences of the two pipes are inverse sequences. The application effectively overcomes the problem of uneven gas distribution in the vertical direction in a large-size ALD+Parylene integrated coating equipment through the double-branch pipe structure with opposite flow directions and inverse sequence increasing pipe diameters. Excellent uniformity of the ALD coating thickness on the substrate is achieved. The coating quality and batch consistency are significantly improved. The precursor raw material is saved. The complete conformal deposition of the Parylene layer is ensured. Therefore, the coating performance and overall process efficiency of the system are synergistically enhanced.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of coating, and particularly relates to a coating system and a coating method. BACKGROUND

[0002] Atomic layer deposition (ALD) and Parylene chemical vapor deposition are two key technologies widely used in high-performance packaging and protective coating. In recent years, an "ALD+Parylene integrated coating equipment" that integrates these two technologies in the same device has appeared on the market, in order to complete the deposition of a dense ALD barrier layer and a highly conformal Parylene protective layer in a single process chamber, thereby significantly improving the water and oxygen barrier life of the device. This integrated coating equipment often needs to handle a large number of workpieces at the same time, so its reaction chamber often has a large size barrel structure (height of 600mm~1000mm).

[0003] ALD is a surface self-limiting reaction, and its film thickness uniformity directly depends on whether the number of precursor molecules adsorbed on the surface of each substrate in each cycle is absolutely equal. For large-size chambers, any slight unevenness in gas distribution will be amplified. The precursor (such as TMA) usually has a large molecular weight and is easily affected by gravity to form a vertical concentration gradient in long-path diffusion. The existing top gas inlet or equal-diameter distribution scheme cannot compensate for the inherent pressure loss along the pipeline of the gas, resulting in differences in the actual amount of precursor received by the upper and lower substrates in the chamber, making it difficult to achieve the ALD film thickness uniformity required for Parylene coating on top.

[0004] Although Parylene coating is less sensitive to gas flow distribution than ALD, its monomer is mainly deposited by uniform gas-phase dispersion. However, the final protective effect of the Parylene layer (especially the water resistance) is greatly dependent on the defect-free and ultra-high uniformity of the underlying ALD film. If the ALD layer has thickness differences or local defects due to uneven gas distribution, these imperfections will become channels for water penetration and will be inherited and amplified during subsequent Parylene deposition, resulting in a sharp decline in the water resistance of the overall device and poor batch consistency. Therefore, to achieve high barrier performance and high reliability of the final product of the integrated coating equipment, it is first necessary to ensure that the underlying ALD coating has extremely high uniformity.

[0005] The design goal of the general fluid distribution scheme in the prior art is usually to achieve macro flow balance or reduce pressure loss, rather than to meet the stringent requirements of ALD process on molecular level dose uniformity and surface reaction consistency. These general schemes have never considered, nor can they solve the problem of how to offset the coupled negative effects of gravity sedimentation and pressure loss along the way on two different mechanism film coating processes (especially ALD) in a vertical space of up to 600-1000 mm, nor can they meet the requirements of performing Parylene film coating on the ALD layer.

[0006] Therefore, there is an urgent need in the art for a gas distribution scheme specially used for large-size ALD+Parylene integrated film coating equipment.

[0007] It should be noted that this part of the present application only provides background related to the present application, and does not necessarily constitute prior art or known technology. SUMMARY

[0008] The present application provides a film coating system and a film coating method, which at least solves the technical problem of poor ALD film coating uniformity caused by uneven distribution of reaction gas in the vertical direction in the prior art large-size ALD+Parylene integrated film coating equipment, thereby causing poor overall device barrier performance and low batch consistency.

[0009] In order to achieve the above-mentioned purpose, in a first aspect, the present application provides a film coating system, comprising a reaction cavity, a sample table and at least one gas inlet device arranged in the reaction cavity; the sample table is used for carrying a substrate; the gas inlet device comprises a first branch distribution pipe and a second branch distribution pipe, a plurality of first cavity gas inlet pipes are arranged on the first branch distribution pipe, a plurality of second cavity gas inlet pipes are arranged on the second branch distribution pipe, and the plurality of first cavity gas inlet pipes and the plurality of second cavity gas inlet pipes correspond one by one in the height direction of the reaction cavity; the gas flow direction in the first branch distribution pipe is opposite to the gas flow direction in the second branch distribution pipe; in each branch distribution pipe, the pipe diameter of the plurality of cavity gas inlet pipes gradually increases along the gas flow direction, and the pipe diameter value sequence of the plurality of first cavity gas inlet pipes and the pipe diameter value sequence of the plurality of second cavity gas inlet pipes are inverse sequences.

[0010] Preferably, the gas inlet device further comprises a main gas inlet pipe, the top and bottom of the main gas inlet pipe are independently communicated with one end of the first branch distribution pipe and the second branch distribution pipe, respectively.

[0011] Preferably, the sample table is rotatably arranged at the center of the reaction cavity, the sample table is divided into a plurality of layers for carrying a plurality of substrates along the height direction of the reaction cavity, and the number of layers of the sample table is the same as the number of the first cavity gas inlet pipes or the second cavity gas inlet pipes.

[0012] Preferably, the outlet direction of the first and second cavity gas inlet pipes is configured such that the lower edge of the outflow is flush with the bottom surface of the corresponding layer, and the central axis of the outflow points to the region of the corresponding layer away from the center of the sample table.

[0013] Preferably, in each branch distribution pipe, the maximum pipe diameter of the cavity gas inlet pipe satisfies the following relationship:

[0014]

[0015] wherein, is the maximum pipe diameter of the cavity gas inlet pipe in each branch distribution pipe;

[0016] k is a proportional coefficient, and k is in the range of 0.25-0.4;

[0017] h is the height of a single layer of the sample table.

[0018] Preferably, in each branch distribution pipe, the cavity gas inlet pipe is vertically inserted into the branch distribution pipe;

[0019] In each branch distribution pipe, the length of the cavity gas inlet pipe satisfies the following relationship:

[0020]

[0021] wherein, L is the length of the cavity gas inlet pipe in each branch distribution pipe;

[0022] d is the outer diameter of each branch distribution pipe;

[0023] G is the gap between the outermost periphery of the sample table and the inner wall of the reaction cavity.

[0024] Preferably, in each branch distribution pipe, the increase ratio of the pipe diameter of adjacent cavity gas inlet pipes along the gas flow direction is 10%-30%.

[0025] Preferably, the number of gas inlet devices is two, which are a first gas inlet device and a second gas inlet device arranged at intervals; the first gas inlet device is used to deliver the gas required for the atomic layer deposition process to the reaction cavity, and the second gas inlet device is used to deliver the gas required for the parathyroid hormone chemical vapor deposition process to the reaction cavity.

[0026] Preferably, the coating system further comprises an external gas source assembly connected with the first gas inlet device, the external gas source assembly comprising a first feed source, a second feed source, a first purge source and a second purge source; the first feed source is connected with the reaction cavity through a first feed pipeline, and a first feed valve is arranged between the first feed source and the first feed pipeline; the second feed source is connected with the reaction cavity through a second feed pipeline, and a second feed valve is arranged between the second feed source and the second feed pipeline; the first purge source is also connected with the reaction cavity through the first feed pipeline, and a first flow meter is arranged between the first purge source and the first feed pipeline, and the first purge source and the first feed source are connected in parallel; the second purge source is also connected with the reaction cavity through the second feed pipeline, and a second flow meter is arranged between the second purge source and the second feed pipeline, and the second purge source and the second feed source are connected in parallel.

[0027] Preferably, the first feed source is trimethylaluminum, the second feed source is ozone, and the first purge source and the second purge source are nitrogen.

[0028] Preferably, the coating system further comprises a gas outlet device, the gas outlet device comprising a gas outlet distribution pipe group which is mirror-symmetric with the first gas inlet device, and a gas extraction assembly which is in communication with the gas outlet distribution pipe group.

[0029] In a second aspect, the present application provides a coating method based on the coating system of the first aspect, the coating method comprising uniformly delivering reaction gas to the surface of the substrate in the reaction cavity by using the gas inlet device.

[0030] The coating method comprises at least one atomic layer deposition process and / or one paralyne deposition process.

[0031] Preferably, the coating method specifically comprises:

[0032] Through the first gas inlet device, the first precursor and the second precursor are alternately pulsed into the reaction cavity, and purge gas is introduced after each pulse to form an atomic layer deposition film on the surface of the substrate;

[0033] Through the second gas inlet device, paralyne gas is introduced into the reaction cavity to deposit a paralyne film on the atomic layer deposition film.

[0034] The present application has the following beneficial effects:

[0035] The application solves the core problem of uneven gas distribution in the vertical direction caused by long gas diffusion path, pressure loss along the path and gravity settlement in the 600-1000mm large-size ALD+Parylene integrated coating equipment by adopting the double-branch distribution pipe structure with opposite gas flow direction, increasing pipe diameter along the flow direction and opposite sequence, thereby realizing excellent film thickness uniformity of ALD coating on multi-layer substrates; this not only significantly improves the coating quality and batch consistency, greatly reduces the waste of expensive precursors, but also ensures the conformal deposition of the subsequent Parylene layer due to the uniform and defect-free ALD bottom layer, finally cooperatively improves the barrier performance and process efficiency of the whole device, and reduces the equipment maintenance cost. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments, and it should be understood that the following drawings only show some embodiments of the application, and therefore should not be regarded as a limitation to the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0037] Figure 1 The structural schematic diagram of the coating system provided by the embodiment of the application is shown in the figure.

[0038] Figure 2 The structural schematic diagram of the coating system provided by the embodiment of the application is shown in the figure.

[0039] Explanation of reference signs:

[0040] 10, reaction cavity; 20, sample table; 21, baffle; 30, gas inlet device; 31, main gas inlet pipe; 32, first branch distribution pipe; 321, first cavity gas inlet pipe; 33, second branch distribution pipe; 331, second cavity gas inlet pipe; 40, gas outlet device; 41, gas extraction assembly; 50, external gas source assembly; 51, first feed source; 52, second feed source; 53, first purge source; 54, second purge source; 55, first feed valve; 56, second feed valve; 57, first flow meter; 58, second flow meter. DETAILED DESCRIPTION

[0041] In the application, the positional words such as "up, down, left and right" are generally understood in combination with the positions shown in the drawings and actual applications, unless otherwise stated.

[0042] In addition, the terms "first", "second", etc. are used herein only to describe different instances, and are not used to denote or imply relative importance or a number of indications of the technical features indicated. Thus, the technical features defined with "first", "second", etc. can explicitly or implicitly include one or more of the technical features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0043] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature can be "above", "over" and "on" the second feature, which can be that the first feature is directly above or obliquely above the second feature, or only means that the first feature is horizontally higher than the second feature. The first feature can be "under", "below" and "underneath" the second feature, which can be that the first feature is directly below or obliquely below the second feature, or only means that the first feature is horizontally lower than the second feature.

[0044] The endpoints of the ranges and any values disclosed herein are not limited to the precise values recited as the exact dimensions are not, in some cases, critical to the application. Any numerical value, however, can be expressed as a range to include any and all expressed values between the two values. For example, if a range is stated as 1% to 90%, it is intended that all individual values, or sub-ranges between the upper and lower limits of that range are expressly enumerated. Where a range of values is provided, it is intended to include all values outside of that range as well as those in the range. In other words, "between a and b" encompasses a and b and all integers between a and b. It is further intended that each range include every combination of any of the range limits. For example, a range from 1 to 10 is specifically intended to include individual ranges from 1 to 3, 4, or 5, 6, or 7, 8, or 9, as well as 2 to 10, 3 to 10, 4 to 10, 5 to 10, 6 to 10, and 7 to 10. The same applies to any "and more than" or "or less than" statements. Any reference to a number of an item also means one or more of that item. For example, a reference to "a number of items" means one or more items. The terms "optional", "optionally", and "may" mean that the subsequently described event or circumstance can or can not occur, or that the subsequently described item can or can not be present, and that the description includes items where the event or circumstance occurs or is present and items where it does not.

[0045] As shown in Figure 1 and Figure 2 The present application provides a coating system, which comprises a reaction cavity 10, a sample table 20 and at least one gas inlet device 30 arranged in the reaction cavity 10; the sample table 20 is used for carrying a substrate; the gas inlet device 30 comprises a first branch distribution pipe 32 and a second branch distribution pipe 33, a plurality of first cavity gas inlet pipes 321 are arranged on the first branch distribution pipe 32, a plurality of second cavity gas inlet pipes 331 are arranged on the second branch distribution pipe 33, and the plurality of first cavity gas inlet pipes 321 and the plurality of second cavity gas inlet pipes 331 correspond to each other in the height direction of the reaction cavity 10; the gas flow direction in the first branch distribution pipe 32 is opposite to the gas flow direction in the second branch distribution pipe 33; in each branch distribution pipe, the pipe diameter of the plurality of cavity gas inlet pipes gradually increases along the gas flow direction, and the pipe diameter value sequence of the plurality of first cavity gas inlet pipes 321 and the pipe diameter value sequence of the plurality of second cavity gas inlet pipes 331 are inverse sequences.

[0046] It can be understood that the most core point of the application is the design of the air inlet device 30, which is embodied in "the diameters of the plurality of cavity air inlet pipes gradually increase along the gas flow direction in the branch distribution pipe" and "two branch distribution pipes with opposite gas flow directions and reverse pipe diameter sequences are adopted".

[0047] Regarding "the diameters of the plurality of cavity air inlet pipes gradually increase along the gas flow direction in the branch distribution pipe", this design is mainly to compensate for the pressure loss along the flow path of the gas when flowing through the distribution pipe. When the gas enters from one end of the branch distribution pipe and flows forward, friction will occur between the fluid and the pipe wall, causing the static pressure of the gas to gradually decrease along the flow direction. If the diameters of all cavity air inlet pipes connected to the branch distribution pipe are the same, the air inlet pipe at the front section of the branch pipe (close to the air inlet) will have a larger air outlet flow due to the higher static pressure, while the air inlet pipe at the end section of the branch pipe (far from the air inlet) will have a smaller air outlet flow due to the decay of static pressure. This flow difference will directly lead to uneven gas concentration in different height regions of the reaction cavity 10, thereby destroying the uniformity of the film coating. By gradually increasing the diameters of the cavity air inlet pipes along the gas flow direction, this pressure loss can be effectively compensated. The increase in diameter means that the flow resistance of the air outlet is reduced, so that even at a lower static pressure, a substantially equal air outlet flow can be achieved through the physical mechanism of balancing with the air outlet of the small-diameter, high-flow-resistance air inlet pipe at the front end, thereby ensuring that the gas flow from each cavity air inlet pipe is substantially consistent.

[0048] Regarding the adoption of "two branch distribution pipes with opposite gas flow directions" and "pipe diameter sequences in reverse order", this is a further optimization of the above-mentioned single-pipe variable-diameter compensation scheme, aiming to achieve higher precision uniformity. Even if a single branch distribution pipe adopts a variable-diameter design, the compensation effect may still have slight deviations due to processing errors, gas flow fluctuations, or incomplete accuracy of the calculation model. For example, Figure 1 and Figure 2As shown, the arrows in the figure point to the direction of the flow of the gas, and the application ingeniously provides two branch distribution pipes, one of which sends gas from top to bottom, and the diameter of the gas inlet pipe thereon is arranged from small to large; the other sends gas from bottom to top, and the sequence of the diameter of the gas inlet pipe thereon is just the reverse of the above set, i.e. from large to small. In this way, for the same height layer in the reaction cavity 10, it will simultaneously receive gas from two branch distribution pipes: one from the first cavity gas inlet pipe 321 with larger diameter (smaller flow resistance) in the first branch distribution pipe 32, and the other from the second cavity gas inlet pipe 331 with smaller diameter (larger flow resistance) in the second branch distribution pipe 33. Since the flow directions of the two branch distribution pipes are opposite, they naturally form a complement in flow resistance and pressure distribution. Any slight flow imbalance that cannot be completely compensated in a single branch distribution pipe will be compensated and neutralized again at the intersection of the other reverse sequence branch distribution pipe. This two-way hedging design greatly improves the control ability and robustness of the gas distribution uniformity in the vertical direction of the entire reaction cavity 10.

[0049] In summary, the above arrangement solves the problem of uniform gas distribution in the large-size ALD+Parylene integrated coating equipment. The application solves the core problem of uneven gas distribution in the vertical direction in large-size ALD+Parylene integrated coating equipment caused by long gas diffusion path, pressure loss along the way and gravity settlement by adopting a double-branch distribution pipe structure with opposite gas flow directions, increasing pipe diameters along the flow direction, and reverse sequences. Thus, excellent film thickness uniformity of ALD coating on the substrate is achieved; this not only significantly improves the coating quality and batch consistency, greatly reduces the waste of expensive precursors, but also ensures the conformal deposition of the subsequent Parylene layer due to the uniform and defect-free ALD bottom layer, ultimately synergistically improves the barrier performance and process efficiency of the overall device, while reducing the equipment maintenance cost.

[0050] Preferably, as Figure 1 and Figure 2As shown, the gas inlet device 30 further comprises a main gas inlet pipe 31, the top and bottom of which are respectively and independently communicated with one end of the first branch distribution pipe 32 and the second branch distribution pipe 33. The above arrangement aims to construct a symmetrical distribution system capable of naturally forming reverse airflow. Specifically, the middle part of the main gas inlet pipe 31 is provided with a total gas inlet for accessing external gas source. When the reaction gas or purge gas enters the main gas inlet pipe 31 from the middle gas inlet, the airflow will naturally flow to the upper and lower ends of the main gas inlet pipe 31 according to the principle of fluid dynamics. The gas flowing out of the top of the main gas inlet pipe 31 will enter one end of the first branch distribution pipe 32, while the gas flowing out of the bottom of the main gas inlet pipe 31 will enter one end of the second branch distribution pipe 33. Since the two gas flows are from the same main pipe in opposite directions, their flow directions in the first branch distribution pipe 32 and the second branch distribution pipe 33 are naturally set to be opposite. For example, if the gas in the first branch distribution pipe 32 flows from top to bottom, the gas in the second branch distribution pipe 33 must flow from bottom to top. This single-point gas inlet, two-way gas distribution design efficiently and reliably realizes the prerequisite of opposite gas flow directions in the two branch distribution pipes without complex valves or control systems.

[0051] It should be particularly pointed out that this connection mode of middle gas inlet through the main gas inlet pipe 31 is only a preferred embodiment for realizing the above-mentioned reverse airflow effect, and is not a limitation of the present application. The core idea of realizing opposite gas flow directions in the two branch distribution pipes can be implemented in various ways. For example, the middle gas inlet main gas inlet pipe 31 can be removed, and two external gas inlets can be respectively and independently arranged at the top end of the first branch distribution pipe 32 and the bottom end of the second branch distribution pipe 33 (or the bottom end of the first branch distribution pipe 32 and the top end of the second branch distribution pipe 33). As long as the relative directions of gas entering the two branch distribution pipes are opposite, the technical solution requirements can also be met.

[0052] Preferably, as shown in Figure 1 and Figure 2 The sample table 20 is rotatably arranged at the center of the reaction cavity 10, and the sample table 20 is divided into multiple layers along the height direction of the reaction cavity 10 for carrying multiple substrates, and the number of layers of the sample table 20 is the same as the number of the first cavity gas inlet pipe 321 or the second cavity gas inlet pipe 331.

[0053] The present application sets the sample table 20 as a multi-layer structure along the height direction of the cavity, which can maximize the production capacity of a single process operation. Through the stacking of vertical space, this design enables one reaction cavity 10 to simultaneously carry and process multiple substrates, which greatly improves the space utilization and production throughput of the equipment compared with the traditional single-layer sample table 20, and significantly reduces the production cost per unit product.

[0054] The number of layers of the sample table 20 is the same as the number of cavity gas inlet pipes on one branch distribution pipe, which can ensure that the gas uniform distribution technology of the present application can act on each layer of substrate. The core of the present application is to establish a uniform gas concentration distribution in the cavity height direction through the gas inlet device 30, and each cavity gas inlet pipe is responsible for providing reaction gas for a specific height area. If the number of layers of the sample table 20 does not match the number of gas inlet pipes, some layers will not be supplied with gas, or some gas inlet pipes will waste gas in the empty area, thereby destroying the overall uniformity.

[0055] The multi-layer sample table 20 of the present application has a rotating function, which can solve the problem of uniformity of film coating in the substrate plane (i.e. the circumferential direction). Although the gas inlet device 30 ensures the uniformity in the vertical direction, the gas may still have distribution differences in the horizontal plane due to slight flow field disturbance, temperature gradient or asymmetric cavity structure after entering the cavity. By rotating the sample table 20 and all the substrates carried thereon at a uniform speed, it can be ensured that each point on the substrate can obtain a uniform film thickness distribution.

[0056] More preferably, as shown in Figure 1 and Figure 2 , the outermost side of the sample table 20 is also provided with a ring of baffle 21 along its circumferential direction, which can solve the problem of local over-concentration caused by the direct impact of gas on the edge of the substrate. When the reaction gas is sprayed from the lateral distribution pipe, the flow has a certain initial kinetic energy and directionality. In the case where no baffle 21 is provided, this part of the gas flow will directly impact the edge area of the substrate on the outermost periphery of the high-speed rotating sample table 20. The provision of the baffle 21 can effectively block the direct impact of the inlet gas flow on the edge of the substrate, so that the gas flow is buffered, scattered and redistributed before reaching the substrate surface, so as to enter the process area enclosed by the baffle 21 in a more gentle and uniform manner.

[0057] Preferably, as shown in Figure 1 and Figure 2 , the outlet directions of the first cavity gas inlet pipe 321 and the second cavity gas inlet pipe 331 are configured such that the lower edge of the outlet gas flow is flush with the bottom surface of the corresponding layer of substrate, and the central axis of the outlet gas flow points to the area of the corresponding layer away from the center of the sample table 20. The above-mentioned arrangement can effectively avoid the local over-concentration caused by the direct impact of the reaction gas on the substrate surface while ensuring that the gas can efficiently and uniformly cover the entire substrate area, especially the edge portion away from the center.

[0058] Preferably, in each branch distribution pipe, the maximum pipe diameter of the cavity gas inlet pipe satisfies the following relationship:

[0059]

[0060] wherein, is the maximum tube diameter of the cavity gas inlet tube in each branch distribution tube; it can be understood that the maximum tube diameter here refers to the inner diameter, because the inner diameter is directly related to the cross-sectional area and flow distribution of gas flow, and is a key parameter affecting film uniformity.

[0061] k is a proportionality coefficient, the value range of k is 0.25-0.4, which can be 0.25, 0.26, 0.27, 0.28, 0.29, 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.4 and any value between them, preferably the value of k is 0.3. The value range of k is obtained on the basis of theoretical calculation, simulation and experimental verification, and the value of k can be fine-tuned according to the type of gas (such as molecular weight);

[0062] h is the single-layer height of the sample table 20.

[0063] The above setting is a comprehensive consideration of the gas diffusion characteristics and the space constraint of the cavity. When the value of k is not less than 0.25, the tube size can ensure that the gas has sufficient initial dispersion ability after being sprayed out, ensuring that the maximum tube diameter can provide sufficient gas flux and diffusion cross-sectional area, so that it can quickly and uniformly diffuse in the corresponding single-layer height space, effectively covering the entire target area, avoiding the gas jet being too concentrated and difficult to spread due to the too small tube diameter. At the same time, the upper limit of k is set to 0.4, which is a necessary restriction on mechanical space, preventing the maximum tube diameter from occupying too much vertical space, thereby avoiding interference with the gas flow field of adjacent layers or structural interference with components such as the sample table 20 and the inner wall of the reaction cavity 10, and ensuring the feasibility of the multi-layer stacking design.

[0064] Preferably, in each branch distribution tube, the cavity gas inlet tube is vertically inserted on the branch distribution tube;

[0065] In each branch distribution tube, the length of the cavity gas inlet tube satisfies the following relationship:

[0066]

[0067] wherein, L is the length of the cavity gas inlet tube in each branch distribution tube;

[0068] d is the outer diameter of each branch distribution tube;

[0069] G is the gap between the outermost periphery of the sample table 20 and the inner wall of the reaction cavity 10.

[0070] ​The length of the cavity gas inlet pipe meets the above relationship, because it ensures that the entire gas inlet device can work safely and reliably in the limited physical space of the reaction cavity 10, while not affecting the core process performance. Meeting the above relationship can prevent the high-speed rotating sample table 20 or the substrate carried thereon from colliding or scratching with the static gas inlet distribution pipe set during operation, thereby ensuring the safe operation of the equipment. In addition, this size limitation also ensures that the gas inlet device 30 does not protrude excessively into the flow field, avoiding the destruction of the laminar flow pattern in the cavity or the generation of unnecessary turbulence due to physical obstruction.

[0071] Preferably, in each branch distribution pipe, the increase ratio of the pipe diameter of the adjacent cavity gas inlet pipe along the gas flow direction is 10% to 30%, which can be 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, and any value therebetween.

[0072] The present application sets the increase ratio of the pipe diameter of the adjacent cavity gas inlet pipe to be 10% to 30%, which is an engineering optimization range determined based on the required flow resistance adjustment range for effective compensation of the pressure loss along the branch distribution pipe. The purpose of setting this ratio range is to balance the pressure decay caused by pipe friction by precisely regulating the flow resistance of each gas outlet. If the increase ratio of the adjacent pipe diameter is less than 10%, the flow resistance reduction will not be sufficient to compensate for the pressure loss from the previous pipe section to the next pipe section, resulting in a significant decrease in the gas outlet flow rate at the end of the branch pipe, which cannot achieve uniform distribution. Conversely, if the increase ratio exceeds 30%, the flow resistance of the outlet of the next section pipe may decrease sharply, resulting in a flow rate that is much greater than that of the previous section, causing new flow unevenness. Therefore, this empirical ratio range of 10% to 30% is a key parameter obtained through fluid mechanics theory calculation, a large number of simulations and experimental tests, which ensures that the flow rate of each gas outlet can be adjusted to a highly consistent state when the gas flows through the entire branch distribution pipe.

[0073] In a specific embodiment, the total height of the reaction cavity of the coating system is 600 mm, the sample table is a rotatable five-layer structure, each layer has a height h = 100 mm, and is used to carry five substrates. Correspondingly, five cavity gas inlet pipes are arranged on each of the first branch distribution pipe and the second branch distribution pipe to realize one-to-one correspondence with the sample table layers. Taking the first branch distribution pipe (gas flow direction from top to bottom) as an example, the inner diameters of the five first cavity gas inlet pipes thereon are designed according to the principle of increasing the pipe diameter along the flow direction, and the specific numerical sequence is: 17.2 mm, 19.6 mm, 22.5 mm, 25.9 mm, 30.0 mm. Among them, the maximum pipe diameter =30.0mm, according to the single layer height h, the scale factor k=0.3 can be obtained, which falls within the preferred range of 0.25~0.4 of the present application, ensuring sufficient diffusion capacity of the gas in the single layer space. At the same time, the increasing proportion of the adjacent pipe diameter is about 14.0%, 14.8%, 15.1% and 15.8% in turn, all of which meet the interval of 10%~30%. The inner diameter sequence of the five second cavity inlet pipes on the second branch distribution pipe (the gas flow direction is from bottom to top) is strictly inverse to that of the first branch distribution pipe, i.e. 30.0mm, 25.9mm, 22.5mm, 19.6mm, 17.2mm. This pipe diameter sequence design, combined with the opposite gas flow direction in the two pipes, constitutes the core reverse compensation mechanism of the present application. In a 600mm high cavity, this specific embodiment successfully realizes that the ALD thin films on the five layers of substrates all have excellent thickness uniformity.

[0074] Preferably, as shown in Figure 1 and Figure 2 , the number of gas inlet devices 30 is two, which are a first gas inlet device and a second gas inlet device arranged at intervals; the first gas inlet device is used to deliver the gas required for the atomic layer deposition process to the reaction cavity 10, and the second gas inlet device is used to deliver the gas required for the parviline chemical vapor deposition process to the reaction cavity 10.

[0075] Preferably, as shown in Figure 1 , the coating system further comprises an external gas source assembly 50 connected with the first gas inlet device; the external gas source assembly 50 comprises a first feed source 51, a second feed source 52, a first purge source 53 and a second purge source 54; the first feed source 51 is connected with the reaction cavity 10 through a first feed pipeline, and a first feed valve 55 is arranged between the first feed source 51 and the first feed pipeline; the second feed source 52 is connected with the reaction cavity 10 through a second feed pipeline, and a second feed valve 56 is arranged between the second feed source 52 and the second feed pipeline; the first purge source 53 is also connected with the reaction cavity 10 through the first feed pipeline, and a first flow meter 57 is arranged between the first purge source 53 and the first feed pipeline, and the first purge source 53 and the first feed source 51 are connected in parallel; the second purge source 54 is also connected with the reaction cavity 10 through the second feed pipeline, and a second flow meter 58 is arranged between the second purge source 54 and the second feed pipeline, and the second purge source 54 and the second feed source 52 are connected in parallel.

[0076] Preferably, the first feed source 51 is trimethylaluminum (TMA), the second feed source is ozone, and the first purge source 53 and the second purge source 54 are nitrogen. The chemical system applicable to the present system is extensive. In addition to TMA / O3 for depositing Al2O3, by replacing the precursor source in the external gas source assembly 50, the present system can be used to deposit thin films of other types of materials, such as other metal oxides (such as TiO2, HfO2), nitrides (such as TiN) or metals, etc.

[0077] The following describes a typical ALD working cycle of the system with the deposition of aluminum oxide (Al2O3) film as an example to demonstrate its working principle:

[0078] S1, open the first feed valve 55, and the TMA precursor vapor is carried by the nitrogen carrier gas into the main gas inlet pipe 31, and then uniformly delivered to the multiple layers of the rotating sample table 20 through the first branch distribution pipe 32 and the second branch distribution pipe 33, and chemically adsorbed on the substrate surface.

[0079] S2, close the first feed valve 55, and the nitrogen continues to enter the reaction chamber 10 through the pipeline to completely remove the residual TMA molecules and reaction byproducts in the chamber through the mirror-symmetrical gas outlet device 40.

[0080] S3, open the second feed valve 56, and the ozone is uniformly delivered to the multiple layers of the sample table 20 through the gas distribution system of the application, and reacts with the TMA adsorbed on the substrate surface to form an aluminum oxide layer.

[0081] S4, close the second feed valve 56, and the nitrogen enters the chamber again to remove excess ozone and reaction byproducts.

[0082] By repeating the above four steps, an aluminum oxide film of the desired thickness can be grown on the substrate surface atom by atom. The system ensures that the precursor dose received by each substrate surface in each ALD cycle is highly consistent through precise and balanced gas distribution, thereby achieving excellent film thickness uniformity.

[0083] After forming an atomic layer deposition film on the substrate surface through the first gas inlet device, a parylene film can also be deposited on the substrate surface that has completed atomic layer deposition through the second gas inlet device. The specific film plating method can be referred to in the Chinese patent with the publication number CN120082871B, which will not be described here in detail.

[0084] Preferably, as shown in Figure 1 and Figure 2 The film plating system further comprises a gas outlet device 40, which comprises a set of mirror-symmetrical gas outlet distribution pipes with the first gas inlet device, and an exhaust assembly 41 communicating with the set of gas outlet distribution pipes. The gas outlet device 40 is mirror-symmetrical in structure with the first gas inlet device. It also contains a set of branch distribution pipes and chamber outlet pipes with the same structure, arranged on the side opposite to the first gas inlet device in the reaction chamber 10. The gas outlet device 40 is in communication with the exhaust assembly 41 (such as a vacuum pump) through a pipeline.

[0085] The mirror-symmetrical gas outlet design is not only for discharging exhaust gas. Its key role is to maintain and guide the gas flow pattern. After the gas enters from the nozzles of each layer of the first gas inlet device, it will flow horizontally across the substrate surface under the driving of pressure difference, and then be captured by the suction port of the corresponding gas outlet device 40 at the same height and discharged. This establishes a series of relatively independent and parallel horizontal gas flow channels for each layer of substrate. This design effectively avoids the vertical turbulent flow of gas in the cavity, ensures that the gas entering from the nth layer can be mainly discharged from the nth layer, prevents cross contamination and turbulence between layers, and ensures that the gas remains uniform in height after crossing the reaction cavity 10.

[0086] It can be understood that the gas outlet device 40 is opposite to the first gas inlet device, and the second gas inlet device is spaced apart from the first gas inlet device to facilitate the arrangement of external devices.

[0087] Each improvement of the mechanical structure of the film coating system provided by the present application is a targeted design closely around the core goal of "how to achieve ALD film coating ultra-high uniformity in a large-size ALD+parathyroid hormone integrated film coating equipment". Those skilled in the art should understand that the application scenario, design purpose and technical effect of the mechanical structure in the present application have specificity.

[0088] The proportional parameters (such as an increase of 15%~35%, and the maximum pipe diameter coefficient k=0.25~0.4) of the variable-diameter design of the present application are determined by accurate calculation and simulation of the fluid dynamics characteristics of ALD precursors (such as TMA) under specific process pressure and flow rate, aiming to compensate the precursor dose uniformity which is crucial in ALD process, rather than simply balancing the flow. The design goal is to make the number of molecules chemisorbed on each piece of substrate surface consistent, which is the prerequisite for achieving atomic-level uniform deposition.

[0089] A single variable-diameter branch pipe may improve uniformity to some extent, but it is difficult to make ALD layers stable and uniform enough to perform parathyroid hormone coating on them in a large-scale cavity. The "double gas flow collision, pipe diameter sequence reverse" design of the present application constitutes a cooperative compensation system. It not only compensates for the pressure loss along the way, but also actively corrects systematic errors caused by factors such as gravity, temperature fluctuations, and cavity geometric asymmetry. This design ensures that even at the topmost and bottommost layers, the substrate can receive precisely compensated gas flow from two directions, thereby reducing the vertical concentration gradient to near zero.

[0090] The first gas inlet device of the present application cooperates with the mirror-symmetrical gas outlet device 40 to establish stable and parallel horizontal laminar flow in the cavity for each layer of substrate. This flow field form is optimal for the surface reaction of ALD and avoids the shadow effect of film plating caused by vortex flow. More importantly, the uniform ALD bottom layer enables the conformal deposition of the parylene layer thereon without defects, and the combination of the two ultimately achieves the ultimate film thickness uniformity and excellent barrier performance that cannot be achieved by a single process.

[0091] Therefore, the mechanical structure of the present application is an organic whole constructed to solve the specific technical problem (excellent uniformity) in the specific application scenario (ALD + parylene integrated film plating equipment). It realizes the uniformity of ALD film plating and parylene film plating in a large-scale cavity, which is unpredictable and unachievable by any general or target different gas distribution scheme in the prior art.

[0092] The present application also provides a film plating method, which comprises uniformly delivering reaction gas to the surface of the substrate in the reaction cavity 10 by using the gas inlet device 30.

[0093] The film plating method at least comprises one atomic layer deposition and / or one parylene deposition process.

[0094] Preferably, the film plating method specifically comprises:

[0095] Through the first gas inlet device, the first precursor and the second precursor are alternately pulsed into the reaction cavity 10, and a purge gas is introduced after each pulse to form an atomic layer deposition film on the surface of the substrate.

[0096] Through the second gas inlet device, parylene gas is introduced into the reaction cavity 10 to deposit a parylene film on the atomic layer deposition film.

[0097] The film plating method of the present application establishes a highly uniform gas distribution field in the reaction cavity 10 by using the gas inlet device 30 with a double inverse sequence variable diameter structure, so that each layer of substrate surface can obtain a completely consistent precursor adsorption dose during the atomic layer deposition stage, thereby realizing excellent film thickness uniformity. The parylene deposition carried out on this basis can realize complete conformal deposition due to the uniform and defect-free coverage of the ALD film, and the synergistic effect of the two not only significantly improves the overall density and barrier performance of the composite film layer, but also fundamentally guarantees the high consistency of product performance between batches, while reducing the waste of precursors through precise gas control, thereby improving the process efficiency and product yield.

[0098] The preferred embodiments of the present application are described in detail above, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including that each technical feature is combined in any other suitable manner. These simple modifications and combinations should also be considered as disclosed by the present application and fall within the protection scope of the present application.

Claims

1. A coating system, characterized by, The coating system comprises a reaction cavity, a sample table and at least one gas inlet device arranged in the reaction cavity; the sample table is used for carrying substrates; The gas inlet device comprises: a first branch distribution pipe and a second branch distribution pipe, a plurality of first cavity gas inlet pipes are arranged on the first branch distribution pipe, a plurality of second cavity gas inlet pipes are arranged on the second branch distribution pipe, and the plurality of first cavity gas inlet pipes and second cavity gas inlet pipes correspond to each other in the height direction of the reaction cavity; The gas flow direction in the first branch distribution pipe is opposite to the gas flow direction in the second branch distribution pipe; In each branch distribution pipe, the pipe diameter of the plurality of cavity gas inlet pipes gradually increases along the gas flow direction, and the pipe diameter value sequence of the plurality of first cavity gas inlet pipes and the pipe diameter value sequence of the plurality of second cavity gas inlet pipes are inverse sequences of each other; The sample table is rotatably arranged at the center of the reaction cavity, the sample table is divided into a plurality of layers along the height direction of the reaction cavity for carrying a plurality of substrates, and the number of layers of the sample table is the same as the number of the first cavity gas inlet pipes or the second cavity gas inlet pipes; The outlet direction of the first cavity gas inlet pipe and the second cavity gas inlet pipe is configured such that the lower edge of the gas outlet flow is flush with the bottom surface of the corresponding layer of substrates, and the central axis of the gas outlet flow points to the area of the corresponding layer away from the center of the sample table; In each branch distribution pipe, the maximum pipe diameter of the cavity gas inlet pipe satisfies the following relationship: wherein, assigning a maximum pipe diameter of the lumen intake pipe to each branch; k is a proportionality coefficient, and the value range of k is 0.25-0.4; h is the height of a single layer of the sample table; In each branch distribution pipe, the increase ratio of the pipe diameter of adjacent cavity gas inlet pipes along the gas flow direction is 10%-30%.

2. The coating system of claim 1, wherein, The gas inlet device further comprises a main gas inlet pipe, the top and bottom of the main gas inlet pipe are respectively and independently communicated with one end of the first branch distribution pipe and the second branch distribution pipe.

3. The coating system of claim 1, wherein, In each branch distribution pipe, the cavity gas inlet pipe is vertically inserted on the branch distribution pipe; In each branch distribution pipe, the length of the cavity gas inlet pipe satisfies the following relationship: Wherein, L is the length of the cavity gas inlet pipe in each branch distribution pipe; d is the outer diameter of each branch distribution pipe; G is the gap between the outermost periphery of the sample table and the inner wall of the reaction cavity.

4. The coating system according to any one of claims 1 to 3, characterized in that The number of the gas inlet device is two, which are a first gas inlet device and a second gas inlet device arranged at intervals; the first gas inlet device is used for conveying the gas required by the atomic layer deposition process to the reaction cavity, and the second gas inlet device is used for conveying the gas required by the parvulin chemical vapor deposition process to the reaction cavity.

5. The coating system of claim 4, wherein, The coating system further comprises an external gas source assembly connected with the first gas inlet device, and the external gas source assembly comprises: a first feed source, the first feed source is connected with the reaction cavity through a first feed pipeline, and a first feed valve is arranged between the first feed source and the first feed pipeline; a second feed source, the second feed source is connected with the reaction cavity through a second feed pipeline, and a second feed valve is arranged between the second feed source and the second feed pipeline; A first purging source is also connected with the reaction cavity through a first feeding pipeline, a first flow meter is arranged between the first purging source and the first feeding pipeline, and the first purging source and the first feeding source are connected in parallel; A second purging source is also connected with the reaction cavity through a second feeding pipeline, a second flow meter is arranged between the second purging source and the second feeding pipeline, and the second purging source and the second feeding source are connected in parallel.

6. The coating system of claim 5, wherein, The first feeding source is trimethylaluminum, the second feeding source is ozone, and the first purging source and the second purging source are nitrogen.

7. The coating system of claim 4, wherein, The coating system further comprises an air outlet device, the air outlet device comprises a set of air outlet distribution pipes which are mirror-symmetric with the first air inlet device, and an air extraction assembly which communicates with the set of air outlet distribution pipes.

8. A coating method based on the coating system according to any one of claims 1 to 7, characterized in that, The coating method comprises uniformly feeding reaction gas to the surface of the substrate in the reaction cavity by using the air inlet device; The coating method comprises at least one atomic layer deposition process and / or one Parylene deposition process.

9. The coating method according to claim 8, wherein The coating method specifically comprises: Through the first air inlet device, the first precursor and the second precursor are alternately pulsed into the reaction cavity, and purging gas is introduced after each pulse to form an atomic layer deposition film on the surface of the substrate; Through the second air inlet device, Parylene gas is introduced into the reaction cavity to deposit a Parylene film on the atomic layer deposition film.

Images