Rotary coating device and control method thereof

Abstract

The invention provides a rotary coating device and a control method thereof, and relates to the technical field of control. In the invention, at least one gas path is respectively communicated with the inner cavity of the reaction chamber; wherein each gas path is sequentially provided with a gas supply device, an MFC and a reaction source supply device in the direction from the gas path to the inner cavity, the MFC is used for controlling the gas flow of inert gas provided by the gas supply device, and the inert gas is used for introducing a reaction source provided by the reaction source supply device into the inner cavity; the motor controller is used for receiving a first message sent by the MFC, determining the target motor rotating speed of the rotating motor according to the gas flow carried by the first message, and sending a control instruction to the rotating motor; wherein the rotating motor is rotationally connected with a working disc in the inner cavity, the working disc is used for bearing a semiconductor to be coated, and the control instruction is used for instructing the rotating motor to drive the working disc to rotate according to the target motor rotating speed. Therefore, the uniformity of semiconductor coating is improved.

Description

Technical Field

[0001] The present application relates to the field of control technology, and in particular to a rotary coating device and a control method thereof. Background Art

[0002] In the thin film deposition (i.e. coating) process of semiconductor manufacturing, Figure 1 The coating device shown is for semiconductor (e.g., wafer) coating, and by alternately introducing reaction sources (e.g., source_1 and source_2), a thin film is deposited layer by layer on the surface of the wafer on the working disk. Figure 1 As shown, first, the gas flow rate can be controlled by an inert gas (such as nitrogen (N2)) and a first mass flow controller (MFC). Under the inert gas, source_1 is introduced into the inner cavity of the reaction chamber, and source_1 forms a single adsorption layer on the surface of the wafer. Next, the unadsorbed source_1 and by-products can be purged with an inert gas and discharged from the reaction chamber. Furthermore, the gas flow rate can be controlled by an inert gas and a second MFC. Under the inert gas, source_2 is introduced into the inner cavity of the reaction chamber, and source_2 reacts chemically with the adsorbed source_1 on the wafer surface, so that a thin film (such as an atomic layer film) is generated on the wafer surface. Further, the unreacted source_2 and by-products can be purged with an inert gas and discharged from the reaction chamber. Finally, by cyclically introducing source_1 and source_2 alternately, a thin film is deposited layer by layer until the desired thickness is reached.

[0003] However, the use of the above coating device will cause the semiconductor (such as wafer) coating to have uneven coating due to the uneven gas flow field in the vacuum chamber; and a simple adjustment process cannot solve this problem. Therefore, how to improve the uniformity of semiconductor coating is an urgent problem to be solved. Summary of the invention

[0004] The embodiment of the present application provides a rotary coating device and a control method thereof, which are used to improve the uniformity of semiconductor coating.

[0005] In a first aspect, an embodiment of the present application provides a spin coating device, the device comprising: at least one gas path, a reaction chamber, a motor controller and a rotating motor; wherein: The at least one gas path is respectively connected to the inner cavity of the reaction chamber; wherein each gas path is sequentially provided with a gas supply device, a mass flow controller MFC and a reaction source supply device in a direction along the gas path to the inner cavity, the MFC is used to control the gas flow rate of the inert gas provided by the gas supply device, and the inert gas is used to introduce the reaction source provided by the reaction source supply device into the inner cavity; The motor controller is used to receive a first message sent by the MFC, and determine the target motor speed of the rotating motor according to the gas flow rate carried by the first message, and send a control instruction to the rotating motor; wherein the rotating motor is rotationally connected to a working disk in the inner cavity, the working disk is used to carry a semiconductor to be coated, and the control instruction is used to instruct the rotating motor to drive the working disk to rotate according to the target motor speed.

[0006] In an optional embodiment, a first valve is provided on the gas path between the MFC and the reaction source supply device, and the first valve is used to open the gas path between the MFC and the reaction source supply device when the reaction source supply device provides the reaction source to the reaction chamber; Furthermore, a second valve is provided on the gas path between the reaction source supply device and the reaction chamber, and the second valve is used to open the gas path between the reaction source supply device and the reaction chamber when the reaction source supply device provides the reaction source to the reaction chamber.

[0007] In an optional embodiment, each gas path is further provided with a gas branch, and the gas branch is connected with the MFC and the inner cavity through a corresponding gas path; A third valve is arranged on the gas branch line, and the third valve is used to open the gas branch line within a set time range when the reaction source supply device stops providing the reaction source to the reaction chamber, so that the inert gas provided by the gas supply device can purge the reaction source remaining in the corresponding gas path into the inner cavity, and / or purge the reaction source remaining in the inner cavity out of the inner cavity.

[0008] In an optional embodiment, if the gas flow rate is less than a set first flow rate threshold, the target motor speed is 0; If the gas flow rate is greater than or equal to the first flow rate threshold and less than a set second flow rate threshold, the target motor speed is determined according to the gas flow rate, the motor speed coefficient and the first motor speed, wherein the motor speed coefficient is used to characterize the correlation between the gas flow rate and the target motor speed, and the first motor speed is the motor speed when the gas flow rate is the first flow rate threshold; If the gas flow rate is greater than or equal to the second flow rate threshold, the target motor speed is the second motor speed, and the second motor speed is the motor speed when the gas flow rate is the second flow rate threshold.

[0009] In an optional embodiment, the MFC is used to detect the gas flow rate, and when it is determined that the gas flow rate is greater than or equal to the first flow rate threshold, send the first message to the MFC.

[0010] In an optional embodiment, the device further includes a vacuum pump, which is used to extract the original gas in the reaction chamber before performing a coating operation on the semiconductor to be coated, until the reaction chamber is in a vacuum state.

[0011] In an optional embodiment, the gas outlets of the at least one gas path are the same.

[0012] In a second aspect, an embodiment of the present application further provides a method for controlling the spin coating device as described in the first aspect, the method comprising: In the process of coating a semiconductor to be coated on a working disk in an inner cavity of a reaction chamber by a reaction source provided by a reaction source supply device, detecting a gas flow rate of an inert gas provided by a gas supply device; determining a target motor speed of the rotating motor according to the gas flow rate; The rotating motor is controlled to drive the working disk to rotate according to the target motor speed.

[0013] In an optional embodiment, before detecting the gas flow rate of the inert gas provided by the gas supply device, the method further includes: In response to a reaction source supply request from the reaction source supply device, a first valve and a second valve are opened; the first valve and the second valve are used to open a gas path between the reaction source supply device, the mass flow controller MFC and the reaction chamber when the reaction source supply device provides the reaction source to the reaction chamber; The reaction source is introduced into the inner cavity by the inert gas provided by the gas supply device.

[0014] In an optional embodiment, determining the target motor speed of the rotating motor according to the gas flow rate includes: If the gas flow rate is less than a set first flow rate threshold, determining the target motor speed to be 0; If the gas flow rate is greater than or equal to the first flow rate threshold and less than a set second flow rate threshold, the target motor speed is determined according to the gas flow rate, the motor speed coefficient and the first motor speed; wherein the motor speed coefficient is used to characterize the correlation between the gas flow rate and the target motor speed, and the first motor speed is the motor speed when the gas flow rate is the first flow rate threshold; If the gas flow rate is greater than or equal to the second flow rate threshold, the target motor speed is determined to be the second motor speed; the second motor speed is the motor speed when the gas flow rate is the second flow rate threshold.

[0015] The beneficial effects of this application are as follows: In the rotary coating device provided in the embodiment of the present application, the motor controller can receive the gas flow rate of the inert gas introduced into the gas path reported in real time by the MFC, and determine and adjust the target motor speed of the rotary motor according to the gas flow rate, thereby controlling the rotary motor to drive the working disk carrying the semiconductor to be coated to rotate according to the target motor speed, thereby improving the problem that the semiconductor cannot be uniformly coated by the reaction source due to the uneven gas flow field in the reaction chamber.

[0016] In addition, other features and advantages of the present application will be described in the subsequent description, and partly become apparent from the description, or be understood by practicing the present application. The purpose and other advantages of the present application can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described here are used to provide a further understanding of the present application, constitute a part of the present application, and do not constitute an improper limitation on the present application. In the drawings: Figure 1 A schematic structural diagram of an existing semiconductor coating device provided in an embodiment of the present application; Figure 2 A method based on the embodiment of the present application is provided Figure 1 Schematic diagram of the gas flow field; Figure 3 A schematic structural diagram of a rotating body coating device provided in an embodiment of the present application; Figure 4 A schematic structural diagram of another rotating body coating device provided in an embodiment of the present application; Figure 5 A schematic diagram of a speed partition of a target motor speed provided in an embodiment of the present application; Figure 6A method based on the embodiment of the present application is provided Figure 3 or Figure 4 Schematic diagram of the gas flow field; Figure 7 A method based on the embodiment of the present application is provided Figure 3 or Figure 4 Schematic diagram of the implementation flow of the control method; Figure 8 A logic diagram of a control method for a rotary coating device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] The embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be construed as being limited to the embodiments described herein. Instead, these embodiments are provided to provide a more thorough and complete understanding of the present application. It should be understood that the drawings and embodiments of the present application are only for exemplary purposes and are not intended to limit the scope of protection of the present application.

[0019] It should be understood that the various steps described in the method implementation of the present application can be performed in different orders and / or performed in parallel. In addition, the method implementation may include additional steps and / or omit the steps shown. The scope of the present application is not limited in this respect.

[0020] The term "including" and its variations used in this document are open inclusions, that is, "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments". Relevant definitions of other terms will be given in the description below. It should be noted that the concepts of "first", "second", etc. mentioned in this application are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0021] It should be noted that the modifications of "one" and "plurality" mentioned in the present application are illustrative rather than restrictive, and those skilled in the art should understand that unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0022] The names of the messages or information exchanged between multiple devices in the embodiments of the present application are only used for illustrative purposes and are not used to limit the scope of these messages or information.

[0023] Some of the terms used in the embodiments of the present application are explained below to facilitate understanding by those skilled in the art.

[0024] (1) Wafer: refers to the silicon wafer used to make silicon semiconductor circuits. The raw material is silicon. High-purity polycrystalline silicon is dissolved and mixed with silicon crystal seeds, and then slowly pulled out to form cylindrical single crystal silicon. After grinding, polishing and slicing, the silicon crystal rod is formed into a silicon wafer, also known as a wafer. Domestic wafer production lines are mainly 8-inch and 12-inch.

[0025] (2) Gas circuit: refers to laboratory gas engineering, that is, the connecting pipeline from the gas cylinder to the instrument terminal. In the embodiment of the present application, the gas circuit refers to the gas channel or gas pipeline from the equipment providing inert gas and the reaction source to the reaction chamber used for semiconductor coating.

[0026] (3) Cavity: It describes an object that is sealed off from the outside and hollow inside.

[0027] (4) Purge: Also known as cleaning. In the semiconductor process, a large amount of gas that does not react easily with other gases is usually introduced into the reaction chamber to discharge the unnecessary gas in the chamber. This process is usually called the purge process. The gas used in this process is called purge gas, which is usually an inert gas.

[0028] (5) Reaction source: In the thin film deposition process of semiconductor manufacturing, the reaction source is a key material. It is mainly used in the vapor deposition (for example, physical vapor deposition (PVD), chemical vapor deposition (CVD) and atomic layer deposition (ALD)) coating process to form the thin film materials required for semiconductor manufacturing. It can also be used for semiconductor epitaxial growth, etching, ion implantation doping and cleaning.

[0029] For example, assuming that reaction source 1 is trimethylaluminum (TMA) and reaction source 2 is water (H2O), then the thin film formed on the semiconductor surface through the reaction between reaction source 1 and reaction source 2 may be aluminum dioxide (Al2O3).

[0030] Based on the above-mentioned nouns and related terminology explanations, the design concept of the embodiments of the present application is briefly introduced below: like Figure 1As shown, taking the existing coating device as an ALD coating device as an example, the ALD coating device has a single chamber (i.e., only one reaction chamber) and a single exhaust outlet structure (i.e., the gas outlets of multiple gas paths finally entering the reaction chamber are the same outlet), and by alternately introducing two reaction sources (i.e., source_1 and source_2), a semiconductor to be coated (i.e., a wafer) carried on a workbench (or work disk) is deposited layer by layer (i.e., coated).

[0031] Exemplarily, the main steps of coating a wafer with the ALD coating device include the following: 1) Reaction source adsorption: The gas flow rate of the first gas path is controlled by the first MFC, and source_1 is introduced into the inner cavity of the reaction chamber under the influence of an inert gas (eg, N2), and source_1 forms a single adsorption layer on the surface of the wafer.

[0032] 2) The first purge process: Use inert gas to clean or purge source_1 and by-products that are not adsorbed on the wafer surface and discharge them out of the reaction chamber.

[0033] 3) Reaction to form a thin film: The gas flow rate of the second gas path is controlled by the second MFC. Under the influence of an inert gas (such as N2), source_2 is introduced into the inner cavity of the reaction chamber. On the surface of the wafer, source_2 reacts chemically with the adsorbed source_1, so that a thin film (such as an atomic layer film) is formed on the surface of the wafer, that is, the wafer is coated.

[0034] 4) Second purge process: Use inert gas to clean or purge source_2 and by-products that are not adsorbed on the wafer surface and discharge them out of the reaction chamber.

[0035] 5) Repeat the cycle: By alternately introducing source_1 and source_2, thin films are deposited layer by layer until the desired thickness is reached.

[0036] However, in Figure 1 In the coating device shown, due to the non-uniformity of the gas flow field in the vacuum reaction chamber and the fixed structure of the working plate, the wafer may be coated unevenly. Figure 2 As shown, the flow field near the working disk can be divided into a core flow field area and an edge flow field area. In addition, a simple adjustment process cannot solve the above problems.

[0037] In view of this, in order to solve the problem that the gas flow field in the reaction chamber is uneven, resulting in the inability to effectively and uniformly coat each area of ​​the semiconductor (such as a wafer). Figure 3As shown, the spin coating device may include: at least one gas path 11 (for example, Figure 3 The gas path 11a and the gas path 11b shown in the figure), the reaction chamber 12, the motor controller 13 and the rotating motor 14; wherein, The gas path 11a and the gas path 11b are respectively connected to the inner cavity 12a of the reaction chamber 12. Each gas path may be provided with a gas supply device, an MFC and a reaction source supply device in sequence along the direction from the gas path to the inner cavity 12a. Figure 3 As shown, a gas supply device 151, an MFC 161 and a reaction source supply device 171 are sequentially arranged along the direction from the gas path 11a to the inner cavity 12a, and a gas supply device 152, an MFC 162 and a reaction source supply device 172 are sequentially arranged along the direction from the gas path 11b to the inner cavity 12a. Each MFC can be used to control the gas flow rate of the inert gas provided by the corresponding gas supply device, and the inert gas can be used to introduce the reaction source provided by the corresponding reaction source supply device into the inner cavity 12a.

[0038] It should be noted that the gas supply device 151 and the gas supply device 152, as well as the MFC 161 and the MFC 162 can be different devices (such as Figure 2 As shown), of course, it can also be the same device, and this embodiment of the present application is not limited to this.

[0039] The motor controller 13 may be configured to receive a first message sent by the MFC 161 and / or the MFC 162 , determine a target motor speed of the rotating motor 14 according to the gas flow rate carried in the first message, and send a control instruction to the rotating motor 14 .

[0040] The rotating motor 14 is rotatably connected to the working disk 12a1 in the inner cavity 12a. The working disk 12a1 can be used to carry the semiconductor to be coated (not in Figure 3 As shown), the control instruction can be used to instruct the rotating motor 14 to drive the working disk 12a1 to rotate according to the target motor speed.

[0041] The following is a brief introduction to the various modules and components involved in the above-mentioned spin coating device: In the embodiments of the present application, the number of gas paths in the spin coating device is not specifically limited. For example, there may be more gas paths (for example, 3 gas paths), or of course, there may be fewer gas paths (for example, only 1 gas path).

[0042] In addition, the gas outlets of different gas paths can be the same or different. Figure 1 or Figure 2As shown, the gas outlets of different gas paths are the same, that is, the same gas outlet. In order to ensure the stability of the gas flow field in the reaction chamber, the gas outlets of at least one gas path 11 (ie, gas path 11a and gas path 11b) in the embodiment of the present application are the same.

[0043] Optionally, the gas flow direction of the gas outlet can be parallel to the disk surface of the working disk 12a1, or can be perpendicular to the disk surface of the working disk 12a1. Of course, it can also be other relationships, which is not limited to the embodiments of the present application.

[0044] In order to further ensure the smooth progress of semiconductor coating, the reaction chamber 12 may also include an outer cavity 12b, and a rotating rod connecting the rotating motor 14 and the working disk 12a1 passes through the outer cavity 12b and the inner cavity 12a. In this way, since there is an outer cavity 12b in addition to the inner cavity 12a used for semiconductor coating, the airtightness of the inner cavity 12a can be ensured, that is, when the inner cavity 12a is coating the semiconductor, the inner cavity 12a is still in a state of being filled with inert gas. In addition, the inner cavity 12a can be a covered structure, that is, including an inner cavity cover, or a coverless structure, which is not limited in the embodiments of the present application.

[0045] Moreover, the above-mentioned design of "inner cavity 12a+outer cavity 12b" can reduce the consumption of reaction sources to a certain extent. Moreover, a heating device (such as a heating wire) is provided on the outer cavity 12b, which can well improve the required heat of the inner cavity. In this way, there is no need to arrange a heating device in the inner cavity, which can reduce pollution and improve the coating quality.

[0046] The motor controller 13 can be electrically connected to the MFC 161 and / or MFC 162 to ensure that the MFC 161 and / or MFC 162 can send the first message carrying the gas flow to the motor controller 13. In other words, the motor controller 13 and the MFC 161 and / or MFC 162 can communicate with each other by wire.

[0047] Optionally, wireless communication can also be used between the motor controller 13 and the MFC 161 and / or MFC 162. Exemplarily, the motor controller 13 can access the network through cellular mobile communication technology to communicate with the MFC 161 and / or MFC 162. The cellular mobile communication technology, for example, includes the fifth generation mobile communication (5th generation mobile networks, 5G) technology or the next generation mobile communication technology. For another example, the motor controller 13 can access the network through short-range wireless communication to communicate with the MFC 161 and / or MFC 162. The short-range wireless communication method, for example, includes wireless fidelity (wireless fidelity, Wi-Fi) technology.

[0048] Similarly, the motor controller 13 can be electrically connected to the rotating motor 14 to ensure that the motor controller 13 can send the control instruction of the rotating motor 14 determined according to the gas flow to the rotating motor 14. Optionally, wireless communication can also be used between the motor controller 13 and the rotating motor 14.

[0049] Exemplarily, the rotating motor 14 may also be a servo motor, that is, an engine or motor that controls the operation of a mechanical element in a servo system. The servo motor can accurately control speed and position accuracy, and can convert a voltage signal into torque and speed to drive a controlled object. Optionally, the rotating motor 14 may also be other types of motors, which are not specifically limited in the embodiments of the present application.

[0050] In addition, since the inner diameter of at least one gas path 11 is usually fixed, MFC 161 and / or MFC 162 can also control the gas flow rate of the inert gas to achieve the purpose of controlling the gas flow rate of the inert gas. Optionally, MFC 161 and / or MFC 162 can send a first message carrying the gas flow rate of the inert gas to the motor controller 13. After receiving the first message, the motor controller 13 determines the gas flow rate of the inert gas at this time according to the first message, thereby calculating the gas flow rate of the inert gas in combination with the inner diameter of the gas path, and then determining the target motor speed of the rotating motor 14.

[0051] In an optional implementation, Figure 3 Or see Figure 4 As shown, the rotary coating device may also include a vacuum pump 18, which may be used to extract the original gas in the reaction chamber 12 before coating the semiconductor to be coated, until the reaction chamber 12 is in a vacuum state. That is, the original gas in the gas path and the reaction chamber 12 is completely exhausted, and the reaction chamber 12 is pumped to the vacuum pressure value of the semiconductor coating process to ensure the reliability of the semiconductor coating. In this way, the inert gas provided by the gas supply device 151 or the gas supply device 152 can be reduced, saving the cost required for semiconductor coating.

[0052] Optional, still as Figure 4 As shown, a first valve 191a may be provided on the gas path between the MFC 161 and the reaction source supply device 171. The first valve 191a may be used to open the gas path between the MFC 161 and the reaction source supply device 171 when the reaction source supply device 171 provides the first reaction source to the reaction chamber 12, that is, the first valve 191a is in an open state.

[0053] In addition, a second valve 192a may be provided on the gas path between the reaction source supply device 171 and the reaction chamber 12. The second valve 192a may be used to open the gas path between the reaction source supply device 171 and the reaction chamber 12 when the reaction source supply device 171 provides the first reaction source to the reaction chamber 12, that is, the valve 192a is in an open state.

[0054] Similarly, a first valve 191b may also be provided on the gas path between MFC 162 and the reaction source supply device 172. The first valve 191b may be used to open the gas path between MFC 162 and the reaction source supply device 172 when the reaction source supply device 172 provides the second reaction source to the reaction chamber 12, that is, the first valve 191b is in an open state.

[0055] In addition, a second valve 192b may be provided on the gas path between the reaction source supply device 172 and the reaction chamber 12. The second valve 192 may be used to open the gas path between the reaction source supply device 172 and the reaction chamber 12 when the reaction source supply device 172 provides the second reaction source to the reaction chamber 12, that is, the valve 192b is in an open state.

[0056] It should be noted that the gas path between the MFC 161 and the reaction source supply device 171 can be referred to as the first sub-gas path, and the gas path between the reaction source supply device 171 and the reaction chamber 12 can be referred to as the second sub-gas path. The gas path between the MFC 162 and the reaction source supply device 172 can be referred to as the third sub-gas path, and the gas path between the reaction source supply device 172 and the reaction chamber 12 can be referred to as the fourth sub-gas path. Of course, the aforementioned four sub-gas paths can also have other names, which are not limited in the present embodiment.

[0057] Based on the above method, the gas path between the gas supply device 151 and the gas supply device 152 to the reaction chamber 12 is opened. In this way, the MFC 161 can assist the first reaction source provided by the reaction source supply device 171 to enter the reaction chamber 12 by controlling the gas flow rate of the inert gas provided by the gas supply device 151, and the MFC 162 can assist the second reaction source provided by the reaction source supply device 172 to enter the reaction chamber 12 by controlling the gas flow rate of the inert gas provided by the gas supply device 152, thereby ensuring that the semiconductor can be smoothly plated later. In addition, the automatic control of the opening and closing of the aforementioned gas path can be realized according to the first valve 191a, the first valve 191b, the second valve 192a and the second valve 192b.

[0058] Optionally, each of the above gas paths may also be provided with a gas branch, and the gas branch is connected to the MFC and the inner cavity 12 through the corresponding gas path. Figure 3As shown, the gas circuit 11a is provided with a gas circuit branch 11a1, which communicates with the MFC 161 and the inner cavity 12a through the gas circuit 11a. Also, the gas circuit 11b is provided with a gas circuit branch 11b1, which communicates with the MFC 162 and the inner cavity 12a through the gas circuit 11b.

[0059] Optionally, a third valve may be provided on the gas branch line. The third valve may be used to open the gas branch line within a set time range (e.g., 30s) when the reaction source supply device stops providing the first reaction source or the second reaction source to the reaction chamber, so that the inert gas provided by the gas supply device can purge the first reaction source or the second reaction source remaining in the corresponding gas path into the inner cavity 12a, and / or purge the first reaction source or the second reaction source remaining in the inner cavity 12a out of the inner cavity 12a.

[0060] It should be noted that the above-mentioned set time range in which the reaction source supply device stops providing the first reaction source or the second reaction source to the reaction chamber is also the set time range in which the first valve is closed and the second valve is closed.

[0061] like Figure 3 As shown, a third valve 193a is provided on the gas branch 11a1. The third valve 193a can be used to open the gas branch 11a1 within a set time range when the reaction source supply device 171 stops providing the first reaction source to the reaction chamber 12, so that the inert gas provided by the gas supply device 151 can purge the first reaction source remaining in the corresponding gas path into the inner cavity 12a, and / or purge the first reaction source provided by the reaction source supply device 171 remaining in the inner cavity 12a out of the inner cavity 12a.

[0062] In addition, a third valve 193b is provided on the gas branch 11b1. The third valve 193b can be used to open the gas branch 11b1 within a set time range when the reaction source supply device 172 stops providing the second reaction source to the reaction chamber 12, so that the inert gas provided by the gas supply device 152 can purge the second reaction source remaining in the corresponding gas path into the inner cavity 12a, and / or purge the second reaction source provided by the reaction source supply device 172 remaining in the inner cavity 12a out of the inner cavity 12a.

[0063] Based on the above method, the gas supply device 151 and the gas supply device 152 introduce inert gas into the gas path 11a1 and the gas path 11b1 to purge the first reaction source and / or the second reaction source remaining in the corresponding gas path and the inner cavity 12a, thereby ensuring the purity of the semiconductor coating, that is, improving the quality of the semiconductor coating.

[0064] Specifically, after the first reaction source provided by the reaction source supply device 171 has been attached to the semiconductor to be coated, the inert gas introduced into the gas path 11a1 by the gas supply device 151 can remove the first reaction source that has not been successfully attached (i.e., remains) in the gas path 11a1 and the inner cavity 12a, so that the second reaction source provided by the subsequent reaction source supply device 172 can be stably attached to the first reaction source, so that the two reaction sources can react better. In addition, after the second reaction source provided by the reaction source supply device 172 has been attached, the inert gas introduced into the gas path 11b1 by the gas supply device 152 can remove the second reaction source that has not been successfully attached (i.e., remains) in the gas path 11b1 and the inner cavity 12a and / or the compounds generated by the first reaction source and the second reaction source, thereby improving the quality of semiconductor coating.

[0065] In addition, since the inert gas introduced into the gas path 11a1 and the gas path 11b1 by the gas supply device 151 and the gas supply device 152 can ensure that the residual first reaction source and / or the second reaction source are purged into the inner cavity 12a to achieve sufficient film coating of the semiconductor. Therefore, the utilization rate of the first reaction source provided by the reaction source supply device 171 and the second reaction source provided by the reaction source supply device 172 is also improved to a certain extent.

[0066] In an optional implementation, after receiving the first message carrying the gas flow of the inert gas sent by MFC 161 and / or MFC 162, the motor controller 13 can parse the gas flow of the inert gas from the first message, and then determine the target motor speed of the rotating motor 14 according to the size of the gas flow.

[0067] For example, the target motor speed of the rotating motor 14 may be determined according to the magnitude relationship between the gas flow rate and the set gas flow rate threshold, which may specifically include the following three situations: Case 1: If the gas flow rate is less than the set first flow rate threshold, the target motor speed is 0.

[0068] The determination method of the target motor speed in the above situation 1 can be expressed as: ,but .in, Indicates the gas flow rate, Indicates the set first flow threshold, Indicates the target motor speed.

[0069] Optionally, the first flow rate threshold may be related to the process of semiconductor coating. For example, the first flow rate threshold may be related to the type of reaction source and the type of semiconductor to be coated, or may be related to the interaction between the reaction source and the semiconductor to be coated, which is not limited in the embodiments of the present application.

[0070] It should also be noted that when the gas flow rate is less than the first flow rate threshold, there is almost no uneven coating or the problem of uneven coating is not obvious when coating the semiconductor. However, when the gas flow rate is greater than or equal to the first flow rate threshold, uneven semiconductor coating is very likely to occur. The first flow rate threshold can be determined based on multiple experimental measurements.

[0071] In an optional implementation, when the gas flow rate is less than the first flow rate threshold, it can also be regarded that the current semiconductor coating does not meet the process requirements of the spin coating. At this time, in order to improve the efficiency of the semiconductor coating, the motor controller 13 can also issue an alarm or other prompt information, and then adjust the gas flow rate to meet the process requirements of the spin coating.

[0072] In situation 1, the working disk 12a1 can be effectively rotated only after the gas flow rate of the inert gas introduced by MFC 161 and / or MFC 162 reaches the requirements of the semiconductor coating process, that is, the rotating motor 14 works.

[0073] On the contrary, when the gas flow rate of the inert gas introduced by MFC 161 and / or MFC 162 does not meet the semiconductor spin coating process, the working disk 12a1 and the rotating motor 14 do not work. In this way, the energy consumption caused by the working disk 12a1 and the rotating motor 14 working all the time can be saved to a certain extent.

[0074] Case 2: If the gas flow rate is greater than or equal to the first flow rate threshold and less than the set second flow rate threshold, the target motor speed may be determined according to the gas flow rate, the motor speed coefficient and the first motor speed.

[0075] The motor speed coefficient can be used to characterize the correlation between the gas flow rate and the target motor speed, for example, the degree of linear correlation. The first motor speed can be the motor speed when the gas flow rate is the first flow rate threshold.

[0076] For example, the calculation formula of the target motor speed in situation 2 can be specifically expressed as follows:

[0077] in, Indicates the target motor speed, Indicates the motor speed coefficient, Indicates the gas flow rate, represents the first motor speed. Therefore, the determination method of the target motor speed in the above situation 2 can be expressed as: ,but .in, Indicates the set second flow threshold.

[0078] Optionally, the motor speed factor above It can be determined based on actual experience or based on a large amount of experimental data including gas flow and motor speed. Of course, the motor speed coefficient mentioned above It may also be determined according to other calculation methods, and the embodiments of the present application do not specifically limit this.

[0079] By adopting the above method, when the gas flow rate of the inert gas introduced by MFC 161 and / or MFC 162 reaches the requirements of the semiconductor coating process, the rotation speed of the working disk 12a1 and the rotating motor 14 can be adjusted in real time as the gas flow rate reported by MFC 161 and / or MFC 162 changes at any time, thereby eliminating the influence of the gas flow in the reaction chamber, ensuring that the semiconductor to be coated can be uniformly coated through the reaction source.

[0080] Case 3: If the gas flow rate is greater than or equal to the second flow rate threshold, the target motor speed is the second motor speed, and the second motor speed is the motor speed when the gas flow rate is the second flow rate threshold.

[0081] The determination method of the target motor speed in the above situation 3 can be expressed as: ,but .in, Indicates the set first flow threshold, Indicates the gas flow rate, Indicates the target motor speed, Indicates the speed of the second motor.

[0082] In addition, assuming that there is a positive correlation between the gas flow rate and the target motor speed, the second motor speed mentioned above can also be understood as the maximum speed value of the target motor speed determined under situation 2.

[0083] In case 3, it can be ensured that after the gas flow rate of the inert gas introduced by MFC 161 and / or MFC 162 exceeds the upper limit value required by the semiconductor spin coating process, the semiconductor to be coated will not be thrown out by the high-speed rotating working disk, so as to ensure the safety of the semiconductor coating process. In other words, when the gas flow rate is greater than or equal to the second flow rate threshold, the working disk 12a1 and the rotating motor 14 will rotate at a constant speed at the maximum operating speed (i.e., the second motor speed).

[0084] It should be noted that the gas flow controlled by MFC 161 or MFC 162 may also have a certain effective range, thereby further improving the safety of the semiconductor coating process. Optionally, the maximum value in the aforementioned effective range may be a set soft limit or a physical limit set for MFC 161 or MFC 162 (i.e., the maximum gas flow that can be controlled). Once the aforementioned soft limit is triggered, a corresponding alarm prompt may be issued.

[0085] It should be understood that the above-mentioned soft limit is also soft protection, and the above-mentioned physical limit is also hard protection.

[0086] Furthermore, in order to improve the utilization rate of the first reaction source provided by the reaction source supply device 171 and the second reaction source provided by the reaction source supply device 172, MFC 161 and MFC 162 can determine the maximum gas flow rate of the inert gas introduced into the gas path according to the second flow threshold, that is, reduce the gas flow rate of the inert gas currently introduced by MFC 161 and MFC 162.

[0087] Optionally, the second motor speed can be determined based on the mass of the semiconductor to be coated and the friction factor between the working disk 12a1 and the contact surface of the semiconductor to be coated. Of course, the second motor speed can also be determined through multiple experimental measurements, which is not specifically limited in the present embodiment.

[0088] For example, see Figure 5 As shown, based on the above cases 1 to 3, the target motor speed can be divided into three speed areas according to the gas flow rate. Dead zone: At this time, the gas flow rate Less than the set first flow threshold ; Speed ​​change area: At this time, the gas flow rate Greater than or equal to the first flow threshold , and is less than the set second flow threshold ; Constant speed zone: At this time, the gas flow rate Greater than or equal to the second flow threshold .

[0089] In an optional implementation, in order to save the signaling overhead required for communication between MFC 161 and / or MFC 162 and the motor controller 13, MFC 161 or MFC 162 can be used to detect the gas flow rate, and when it is determined that the gas flow rate is greater than or equal to the first flow rate threshold set above, send a first message to the motor controller 13.

[0090] In addition, when the gas flow rate is less than the first flow rate threshold set above, the motor controller 13 will not receive the first message from MFC 161 or MFC 162, and does not need to determine the target motor speed of the rotating motor 14 according to the gas flow rate carried in the first message, and does not need to send a control instruction to the rotating motor 14. Therefore, while saving the signaling overhead required for communication between the rotating motor 14 and the motor controller 13, the load of the motor controller 13 is also reduced.

[0091] Since the reaction chamber 12 is in an atmospheric pressure environment before the semiconductor to be coated is coated, in order to ensure the reliability of the semiconductor coating, the air in the reaction chamber 12 needs to be exhausted. Therefore, the gas supply device (gas supply device 151 or gas supply device 152) can introduce an inert gas for a set time (e.g., 5 minutes) into the gas circuit 11a (or gas circuit 11b) before the reaction source supply device (reaction source supply device 171 or reaction source supply device 172) provides the reaction source (first reaction source or second reaction source) to the reaction chamber 12, until the original gas in the reaction chamber 12 and the gas circuit 11a (or gas circuit 11b) is exhausted. It should be understood that the aforementioned set time is also the time required for the gas circuit 11a (or gas circuit 11b) and the reaction chamber 12 to be filled with the inert gas.

[0092] Based on the structural design of the above-mentioned rotary coating device, the working disk 12a1 is driven by the rotary motor 14 to rotate, so that the working disk 12a1 carrying the semiconductor to be coated can automatically adjust the rotation speed of the rotary motor 14 according to the numerical value of the inert gas intake (i.e., the gas flow rate), so that when the flow rate is large, the working disk 12a1 rotates fast, and when the flow rate is small, the working disk 12a1 rotates slowly, thereby ensuring that the reaction source is not affected by the flow rate and the gas path flow field in the reaction chamber 12, so that the reaction source is fully and evenly coated on the semiconductor to be coated. For example, refer to Figure 6 As shown, the flow field near the working disk is basically the core flow field area, with only a small part of the edge flow field area.

[0093] To summarize, in the rotary coating device provided in the embodiment of the present application, the motor controller can receive the gas flow rate of the inert gas introduced into the gas path reported in real time by the MFC, and determine and adjust the target motor speed of the rotary motor according to the gas flow rate, thereby controlling the rotary motor to drive the working disk carrying the semiconductor to be coated to rotate according to the target motor speed, thereby improving the problem that the semiconductor cannot be uniformly coated by the reaction source due to the uneven gas flow field in the reaction chamber.

[0094] Furthermore, based on the same technical concept, the embodiment of the present application also provides a control method for a rotary coating device, which is used to improve the problem of poor uniformity of semiconductor coating caused by uneven gas flow field in the reaction chamber. Figure 7 As shown, it is a schematic diagram of the implementation process of a control method for a spin coating device provided in an embodiment of the present application, and the execution subject is as follows Figure 3 or Figure 4 Taking the spin coating device shown in the figure as an example, the specific implementation process of the method is as follows: S701: In the process of coating a semiconductor to be coated on a working disk in an inner cavity of a reaction chamber by using a reaction source provided by a reaction source supply device, a gas flow rate of an inert gas provided by a gas supply device is detected.

[0095] Exemplarily, when executing step S701, the rotary coating device can monitor the change of the gas flow rate of the inert gas (such as N2) in real time through the MFC when the inert gas passes through the MFC, and report the gas flow rate of the inert gas to the motor controller. At this time, the inert gas passing through the MFC will pass through the reaction source supply device, thereby bringing the reaction source provided by the reaction source supply device into the reaction chamber, and then coating the semiconductor to be coated on the working disk in the inner cavity.

[0096] In an optional implementation, the spin coating device may also respond to a source supply request of the source supply device to open the first valve and the second valve before detecting the gas flow rate of the inert gas provided by the gas supply device. The first valve and the second valve are used to open the gas path between the source supply device, the MFC and the reaction chamber when the source supply device provides the reaction source to the reaction chamber. That is, the gas path is opened to ensure that the inert gas provided by the gas supply device can bring the reaction source provided by the source supply device into the reaction chamber.

[0097] It should be noted that before the rotary coating device performs coating operation on the semiconductor to be coated, it is also necessary to extract the original gas in the reaction chamber through a vacuum pump to ensure the reliability of semiconductor coating. Optionally, a second message can be sent to the vacuum pump through the control system so that the vacuum pump starts working after receiving the second message until the original gas in the reaction chamber is exhausted, that is, the reaction chamber is pumped to the vacuum pressure value of the semiconductor coating process.

[0098] S702: Determine the target motor speed of the rotating motor according to the gas flow rate.

[0099] Optionally, if the gas flow rate is less than the first flow rate threshold value set above, the motor controller can determine that the target motor speed of the rotating motor is 0. If the gas flow rate is greater than or equal to the first flow rate threshold value set above, and less than the second flow rate threshold value set above, the motor controller can determine the target motor speed of the rotating motor according to the gas flow rate, the motor speed coefficient and the first motor speed. If the gas flow rate is greater than or equal to the second flow rate threshold value set above, the motor controller can determine that the target motor speed is the second motor speed.

[0100] For example, when executing step S702, the rotary coating device can receive the first message carrying the gas flow reported by the MFC through the motor controller, and determine the target motor speed of the rotary motor according to the target motor speed determination method corresponding to the gas flow. Further, the motor controller can also generate a control instruction for the rotary motor according to the target motor speed.

[0101] S703: Control the rotating motor to drive the working disk to rotate according to the target motor speed.

[0102] Exemplarily, when executing step S703, the rotary coating device can send a control instruction carrying a target motor speed to the rotary motor after the motor controller generates a control instruction for the rotary motor, so that the rotary motor drives the working disk to rotate according to the target motor speed, thereby improving the uniformity of the semiconductor coating.

[0103] Based on the control method described in the above steps S701 to S703, it is assumed that two reaction sources (i.e., a first reaction source (e.g., source_1) and a second reaction source (e.g., source_2)) and two gas paths are used as an example. Figure 8 As shown, it is a logic diagram of a control method of a rotary coating device provided by an embodiment of the present application. The rotary coating device can realize the semiconductor coating process of "introducing source_1, and the working disk rotates → single layer → purging → introducing source_2, and the working disk rotates → coating → purging". The rotating working disk drives the semiconductor to pass through the airflow outlet area in turn, and the rotation speed is based on the MFC (such as Figure 3 The gas flow rate measured by the MFC1 or MFC2 shown in the figure is transmitted to the motor controller in real time by the MFC signal value (i.e., the first message). The motor controller drives the rotating motor to automatically adjust the speed in real time, and finally the working disk automatically adjusts the speed in real time, thereby ensuring that source_1 and source_2 are fully and evenly coated on the semiconductor. After source_1 and source_2 are attached to the semiconductor, they can be purged to complete the semiconductor coating.

[0104] Furthermore, the coated semiconductor will be transferred out of the reaction chamber, and then the next uncoated semiconductor will be transferred into the reaction chamber and placed on the work plate to start the next semiconductor coating process. Optionally, when coating a semiconductor to be coated, this process can be repeated for multiple film formations according to different film thickness requirements.

[0105] It can be seen that the gas flow rate measured and reported in real time by MFC can be used to adjust the motor speed of the rotating motor at any time, and then the working disk is driven to rotate by the rotating motor to ensure that the semiconductor to be coated on the working disk is evenly coated and is not affected by the gas flow field in the reaction chamber. This can improve the utilization rate of the reaction source while improving the semiconductor coating process.

[0106] Furthermore, it should be understood that what is disclosed above is only a preferred embodiment of the present application, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope covered by the present application.

Claims

1. A spin coating device, characterized in that: include: At least one gas circuit, a reaction chamber, a motor controller and a rotating motor; wherein, The at least one gas path is respectively connected to the inner cavity of the reaction chamber; wherein each gas path is sequentially provided with a gas supply device, a mass flow controller MFC and a reaction source supply device in a direction along the gas path to the inner cavity, the MFC is used to control the gas flow rate of the inert gas provided by the gas supply device, and the inert gas is used to introduce the reaction source provided by the reaction source supply device into the inner cavity; The motor controller is used to receive a first message sent by the MFC, and determine the target motor speed of the rotating motor according to the gas flow rate carried by the first message, and send a control instruction to the rotating motor; wherein the rotating motor is rotationally connected to a working disk in the inner cavity, the working disk is used to carry a semiconductor to be coated, and the control instruction is used to instruct the rotating motor to drive the working disk to rotate according to the target motor speed.

2. The device according to claim 1, characterized in that A first valve is provided on the gas path between the MFC and the reaction source supply device, and the first valve is used to open the gas path between the MFC and the reaction source supply device when the reaction source supply device provides the reaction source to the reaction chamber; Furthermore, a second valve is provided on the gas path between the reaction source supply device and the reaction chamber, and the second valve is used to open the gas path between the reaction source supply device and the reaction chamber when the reaction source supply device provides the reaction source to the reaction chamber.

3. The device according to claim 2, characterized in that Each gas path is also provided with a gas branch, and the gas branch is connected with the MFC and the inner cavity through the corresponding gas path; A third valve is arranged on the gas branch line, and the third valve is used to open the gas branch line within a set time range when the reaction source supply device stops providing the reaction source to the reaction chamber, so that the inert gas provided by the gas supply device can purge the reaction source remaining in the corresponding gas path into the inner cavity, and / or purge the reaction source remaining in the inner cavity out of the inner cavity.

4. The device according to any one of claims 1 to 3, characterized in that If the gas flow rate is less than the set first flow rate threshold, the target motor speed is 0; If the gas flow rate is greater than or equal to the first flow rate threshold and less than a set second flow rate threshold, the target motor speed is determined according to the gas flow rate, the motor speed coefficient and the first motor speed, wherein the motor speed coefficient is used to characterize the correlation between the gas flow rate and the target motor speed, and the first motor speed is the motor speed when the gas flow rate is the first flow rate threshold; If the gas flow rate is greater than or equal to the second flow rate threshold, the target motor speed is the second motor speed, and the second motor speed is the motor speed when the gas flow rate is the second flow rate threshold.

5. The device according to claim 4, characterized in that The MFC is used to detect the gas flow rate, and when it is determined that the gas flow rate is greater than or equal to the first flow rate threshold, send the first message to the MFC.

6. The device according to any one of claims 1 to 3, characterized in that The device also includes a vacuum pump, which is used to extract the original gas in the reaction chamber before performing a coating operation on the semiconductor to be coated, until the reaction chamber is in a vacuum state.

7. The device according to any one of claims 1 to 3, characterized in that The gas outlet of the at least one gas path is the same.

8. A control method for a spin coating device as claimed in any one of claims 1 to 7, characterized in that: include: In the process of coating a semiconductor to be coated on a working disk in an inner cavity of a reaction chamber by a reaction source provided by a reaction source supply device, detecting a gas flow rate of an inert gas provided by a gas supply device; determining a target motor speed of the rotating motor according to the gas flow rate; The rotating motor is controlled to drive the working disk to rotate according to the target motor speed.

9. The method according to claim 8, characterized in that Before the gas flow rate of the inert gas provided by the gas supply device is detected, the method further includes: In response to a reaction source supply request from the reaction source supply device, a first valve and a second valve are opened; the first valve and the second valve are used to open a gas path between the reaction source supply device, the mass flow controller MFC and the reaction chamber when the reaction source supply device provides the reaction source to the reaction chamber; The reaction source is introduced into the inner cavity by the inert gas provided by the gas supply device.

10. The method according to claim 8 or 9, characterized in that The step of determining a target motor speed of the rotating motor according to the gas flow rate comprises: If the gas flow rate is less than a set first flow rate threshold, determining the target motor speed to be 0; If the gas flow rate is greater than or equal to the first flow rate threshold and less than a set second flow rate threshold, the target motor speed is determined according to the gas flow rate, the motor speed coefficient and the first motor speed; wherein the motor speed coefficient is used to characterize the correlation between the gas flow rate and the target motor speed, and the first motor speed is the motor speed when the gas flow rate is the first flow rate threshold; If the gas flow rate is greater than or equal to the second flow rate threshold, the target motor speed is determined to be the second motor speed; the second motor speed is the motor speed when the gas flow rate is the second flow rate threshold.

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