Surface treatment apparatus and pressure control method thereof

Abstract

To provide a technology that can avoid a problem caused by gas supply, improve a rate of non-defective products, and avoid mass production of defective products.SOLUTION: A surface treatment device includes a sample stage on which a workpiece is mounted, and in which a process gas is supplied to the workpiece on the sample stage during process processing, and a gas in the processing chamber is discharged from around the sample stage when surface treating the workpiece in the processing chamber isolated from the atmosphere includes an exhaust port arranged on an outer periphery of the sample stage on which the workpiece is placed and an exhaust path corresponding to the exhaust port, and a pressure regulating valve is disposed within the exhaust path, and opens and closes the pressure regulating valve to control gas exhaust.SELECTED DRAWING: Figure 2a

Description

Technical Field

[0001] The present invention relates to a pressure control method for exhausting gas from a reactor and its surface treatment apparatus. In particular, the present invention is used for a surface treatment apparatus that processes a workpiece using gases such as etching, CVD (chemical vapor deposition), ion diffusion, ion implantation, ashing, and surface modification, and relates to a pressure control method for gas exhaust for controlling the gas flow direction, flow path, and gas flow rate for each flow path to the surface treatment apparatus, and its pressure control apparatus and its pressure control method.

Background Art

[0002] For example, in the production of electrical components such as semiconductor elements, liquid crystal elements, solar cells, MEMS and their measuring instruments, and micro mechanical components, a surface treatment apparatus that processes the surface of a workpiece such as a semiconductor wafer using high purity process gases having various gas characteristics is an important industrial machine that is indispensable in today's world. The surface treatment apparatus can also be referred to as a semiconductor manufacturing apparatus, a substrate processing apparatus, a plasma processing apparatus, or a vacuum processing apparatus.

[0003] In these surface treatment apparatuses, a plurality of each processing chamber, measurement chamber, or pre-treatment chamber and post-treatment chamber are arranged continuously side by side in a cluster shape, and wafers and other workpieces are transferred between the respective chambers, and a cluster apparatus that enables not only single processing but also continuous processing in a plurality of chambers is common. In order to achieve simple and fast conveyance, the conveyance height, wafer lift-up height, and transfer position are standardized in each chamber. By doing so, it becomes easy to change the chamber configuration of the cluster apparatus or replace the chamber itself with a new one in case of failure, improving convenience. Also, with the progress of microfabrication of workpieces, in order to ensure the processing accuracy, it has become essential to convey and process wafers and other workpieces one by one, and it is needless to say that single-piece conveyance is the mainstream.

[0004] In each of these chambers, a stage (electrode) for mounting one workpiece is positioned approximately in the center of the processing chamber. The stage has an internal lift pin that moves up and down to hold the workpiece upwards, or conversely, the stage itself can descend, leaving the workpiece on the lift pin that stops lowered higher, thus allowing the workpiece to be placed on the stage (see Japanese Patent Publication No. 3398936, etc.). A transport wand is inserted into the gap between the stage and the supported workpiece, and the wand can rise to receive the workpiece and then retract to remove the workpiece. Loading the workpiece is achieved by advancing the wand, which is loaded with the workpiece, above the lift pin, descending to transfer the workpiece onto the lift pin, and then the empty wand exiting to remove the workpiece.

[0005] The stage is equipped with temperature control means, electrostatic adsorption means, electromagnetic field application means, and shutter functions for shielding charged particles, sputtered particles, neutral particles, or electromagnetic waves including light, according to the requirements of each processing step.

[0006] A gas outlet is located above the stage, opposite it. The gases, which are supplied as a mixed gas or as individual gases via a flow controller, are grouped according to their properties, such as flammability or combustion supporting properties, and introduced into the processing chamber from multiple gas outlets. Some of the introduced gas is excited and, through reactions with the workpiece, diffusion into the chamber, deposition on the inner surface of the chamber, and collisions with the sputter target surface and chamber walls, is replaced by other substances (reaction products), or remains in the workpiece or chamber. Some clustered particles in the gas phase are discharged from the processing chamber along with unreacted supply gas, reaction products, and volatile gases from the surface.

[0007] There are three possible directions for the discharge of gas in the gas phase. The most commonly used is downward discharge from the cylindrical space between the side of the stage and the wall of the processing chamber. In addition, the gas can be discharged laterally from the outer periphery of the side of the processing chamber, away from the workpiece (see Japanese Patent Publication No. 2015-2349, etc.). Although not put into practical use, attempts were made to discharge the gas upward by alternately providing gas outlets and gas discharge ports. However, with upward gas discharge, it is difficult to avoid the problem of solidified material in the exhaust piping falling or being blown onto the workpiece and adhering as foreign matter, and there are still no examples of this being widely used in mass production machines.

[0008] Incidentally, with the advancement of microfabrication, pulsed discharge, which intermittently applies high-frequency current, and intermittent gas supply have been introduced, and processing rooms capable of accommodating these have also been constructed. Furthermore, processing rooms equipped with gas supply systems that support new gas types that enable processes such as Atomic Layer Etching (ALE), which utilizes chemical reactions to control each step of etching (gas deposition, reaction layer formation, reaction vaporization, and gas replacement) by changing the type of gas used at each stage, and Atomic Layer Deposition (ALD) in thin-film deposition, are also becoming available.

[0009] Furthermore, regarding the challenges of particles incident on the surface of a workpiece at low angles during miniaturization, there is a document titled "Motofumi Suzuki, "Nanomorphic Control of Thin Films by Physical Vapor Deposition Method," Proceedings of the 52nd Joint Conference on Vacuum, Vol. 55, No. 3, 2012, pp. 91-96." [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] Japanese Patent Publication No. 2015-2349 [Patent Document 2] U.S. Patent No. 4,393,896 [Patent Document 3] Japanese Patent Publication No. 2003-45854 [Patent Document 4] Patent No. 3398936 [Non-patent literature]

[0011] [Non-Patent Document 1] Motofumi Suzuki, "Control of Nano-Morphology of Thin Films by Physical Vacuum Deposition Method," Proceedings of the 52nd Joint Conference on Vacuum, Vol. 55, No. 3, 2012, pp. 91-96. [Overview of the project] [Problems that the invention aims to solve]

[0012] In surface reactions such as DCR (Dry Chemical Removal), including plasma ashing, performance is greatly influenced not only by the properties of the workpiece and its controlled temperature, but also by the properties of the gas molecules and reaction products. Gas properties such as size, temperature, mean free path, adhesion probability, reaction probability, diffusion coefficient in the depth direction, surface migration, and the volatility (ease of desorption) of the reaction products all play a role. Generally, increasing the flow rate of the process gas and supplying a large volume to the processing chamber eliminates the gas supply limitation, allowing the reaction rate to stabilize beyond the range affected by insufficient gas supply, improving in-plane uniformity and reproducibility for each process. However, the amount of gas adsorbed to contribute to the surface reaction is less at lower pressures, requiring more time to cover the reaction surface. To achieve precise surface control at a suitable reaction rate in a vacuum, gas control in the so-called intermediate flow region is preferable.

[0013] For gas control in this intermediate flow, we would like to use either a combination of a composite-blade turbomolecular pump (TMP) and a small dry pump (DP), or a large-capacity dry pump (DP) capable of handling high flow rates. Furthermore, since a stage for mounting the workpiece will be provided in the center of the processing chamber, the treated gas exhaust will be discharged horizontally or downwards, as in conventional systems. Similar to processing chambers using TMPs for other low-pressure (0.1-50 Pa) processing, we would like to arrange the TMP, pressure control mechanism, and exhaust piping around the lower part of the stage.

[0014] Incidentally, in the viscous flow and intermediate flow regions, even with equipment configurations that position outlets and exhaust ports coaxially with the gas supply and exhaust, exhaust bias is likely to occur, leading to turbulence where the direction and velocity of gas flow on the workpiece surface are uneven. Due to the significant influence of gas viscosity on gas flow, subtle warping of the workpiece surface, tilt from the chamber's central axis, and the shape of the surrounding walls can all contribute to turbulence. As a result, the surface treatment results become uneven depending on the workpiece's position, reducing the performance of the surface treatment. Furthermore, thermal deformation of the workpiece during processing and complex distortion also contribute to the generation of turbulence. In the past, these problems were solved by rotating the workpiece or by rotating and revolving multiple workpieces. However, this makes the support and handling of the workpieces complicated. In addition, some surface treatment equipment uses electrostatic adsorption of the workpiece onto a stage (electrode) to correct it to be nearly flat along the stage (electrode) surface, but electrostatic adsorption can cause scratches on the back surface of the workpiece, leading to the generation of foreign matter. Furthermore, the stress generated in the workpiece due to shape correction can affect the surface treatment reaction, so electrostatic adsorption is not always possible. Currently, while it is possible to infer the occurrence of non-uniform gas supply and turbulence after treatment from the performance measurement results, there is no way to even know if non-uniform gas flow occurs during the treatment.

[0015] The so-called shower plate method is common, in which gas is ejected from the upper center of the processing chamber relative to the workpiece, and the gas is discharged from the periphery of the workpiece surface, such as the side of the stage or the lower periphery of the stage. As a result, the center of the workpiece surface is affected by a gas component with a high concentration derived from the supplied gas, and as the gas approaches the periphery of the workpiece surface, the concentration of reaction products gradually increases, or the concentration of components derived from the supplied gas decreases. Conventionally, for example, in etching, the temperature of the periphery of the wafer, which is the workpiece, was relatively increased to compensate for the increased reaction rate at the periphery of the wafer and obtain uniform etching performance. Specifically, the temperature of the workpiece surface was controlled by temperature adjustment that increased the temperature towards the approximately concentric periphery of the stage on which the workpiece is mounted. In film deposition, conversely, the temperature was lowered at the periphery of the workpiece surface to compensate for the increased adhesion probability and thus increase the film thickness. However, problems that cannot be solved by this temperature correction alone, such as microscopic shape differences after etching, have become new challenges.

[0016] This is related to narrowing the space above the workpiece and bringing the top plate closer to the workpiece surface in order to control the gas flow and reduce the influence of the surrounding walls. Narrowing the space above the workpiece surface causes the gas flow to flow parallel to the workpiece surface, spreading from the center of the workpiece surface outwards along the surface. This is similar to the case of deposition described in the aforementioned document, "Motofumi Suzuki, "Nanomorphic Control of Thin Films by Physical Vapor Deposition Method", Proceedings of the 52nd Joint Conference on Vacuum, Vol. 55, No. 3, 2012, pp. 91-96," where, upon surface incidence of gas, a shadow area (where the incidence of gas molecules is suppressed) is created on the pattern sidewalls of a certain height. This is a problem not only for film deposition similar to that described in the document, but also when removing workpieces from the workpiece surface during etching. The etching removal reaction is accelerated or decelerated in the shadow area of ​​the gas flow moving from the center outwards of the workpiece surface, which is complexly controlled by the temperature of the workpiece surface, the properties of the incoming gas components, the adhesion probability, the reaction probability, and even the desorption coefficient. For processes that are susceptible to the effects of gas flow, measures are needed to mitigate these effects.

[0017] In particular, in atomic layer-level reaction processes such as ALE and ALD, the influence of the direction of gas incidence on the workpiece surface, caused by the presence of patterns and gas flow, has become significant and cannot be ignored.

[0018] In response to these problems, the example described in Patent Document 1 (Japanese Patent Application Publication No. 2015-2349), which discloses a means for exhausting gas from the side wall of the chamber around the workpiece, collects the gas in a circumferential exhaust passage provided on the outer circumference of the chamber and exhausts it to one location in a circumferential exhaust path along the chamber. Therefore, even if non-uniform gas flow occurs in the viscous flow or intermediate flow regions, there is no means to correct it.

[0019] Furthermore, conventional surface treatment devices have a single pressure control valve for the chamber, but the gas flow changes significantly depending on the installation position and degree of opening of the pressure control valve, which is one of the factors that generates turbulence. The structure utilizes the outer perimeter space of the stage for exhaust, and the gas collected directly below the stage is exhausted by the pressure control valve, but there is no means to control the gas flow in the circumferential direction of the workpiece on the stage.

[0020] Furthermore, in the example described in Patent Document 2 (U.S. Patent No. 4,393,896), if, for example, this pressure regulating valve is placed directly below the stage and the TMP is placed below it to perform pressure control, when high-precision pressure control is required, only one of the many rotor blades is operated. Therefore, if the stage is placed directly above it, the pressure regulating valve itself causes uneven exhaust, which is a problem.

[0021] Furthermore, in the example described in Patent Document 3 (Japanese Patent Publication No. 2003-45854), the pressure in the chamber is controlled by the up-and-down movement of the valve body, but since the exhaust passages around the workpiece are opened and closed simultaneously, there is no means to eliminate the unevenness of the exhaust generated around the workpiece.

[0022] In a process processing chamber disposed in a currently mainstream cluster-type device (cluster type: a configuration in which a plurality of chambers (processing chambers) are arranged in a star shape around a transfer chamber), it is desired that the arrangement state and maintenance method do not vary for each chamber. For this purpose, it is necessary to make the chamber shape and the exhaust path, which is a major component, as uniform as possible to form the same device form.

Means for Solving the Problem

[0023] First, regarding the problem of non-uniform gas flow due to exhaust, the exhaust paths on the side of the stage or the side wall of the stage, or the exhaust paths on the inner wall of the processing chamber are divided into several systems, and a pressure regulating valve is provided for each exhaust system to enable adjustment of the exhaust gas volume for each exhaust system. The several exhaust paths are merged after pressure adjustment and connected to an exhaust means (a combination of a turbo molecular pump (TMP) and a small dry pump (DP), or a dry pump (DP) with a large exhaust volume corresponding to a large flow rate) in a single system.

[0024] This makes it possible to freely control the strengthening or weakening of the exhaust of any exhaust system around the stage. By independently controlling the pressure regulating valve of each system, it becomes possible to swirl and exhaust the process gas supplied above the stage around the stage, or exhaust it uniformly in the direction of each system.

[0025] In order to monitor this exhaust state, perform feedback control, or perform AI control (artificial intelligence control) learned in relation to the surface treatment result, etc., a pressure gauge may be provided for each exhaust system. Based on the value of the pressure gauge monitoring the pressure above or on the stage, the value of the pressure gauge of the collective exhaust pipe after the confluence of each system, and the value of the pressure gauge of each exhaust system, the pressure regulating valve is controlled according to the purpose. A diaphragm pressure gauge is used for the pressure gauge provided in each exhaust system so that the process gas does not directly enter the measurement side. Also, in order to prevent film formation in this diaphragm pressure gauge, the diaphragm pressure gauge may be heated.

[0026] The exhaust port from each chamber in this exhaust system is designed to have an exhaust resistance of less than half the exhaust conductance when the pressure regulating valve is at its maximum opening. In other words, the conductance of the exhaust port is smaller than the conductance when the pressure regulating valve is fully open. Therefore, although the exhaust volume increases when the pressure regulating valve is opened to a larger degree, the pressure felt by the pressure gauge decreases, resulting in a pressure drop. By implementing this basic control so that the pressure gauge values ​​for each exhaust system are the same, uniform exhaust can be achieved from around the stage. Conversely, to randomize the direction of gas exhaust, the opening degree of the pressure regulating valve in each exhaust system can be increased or decreased at regular control intervals according to the program or AI control, thereby changing the pattern of exhaust direction.

[0027] Furthermore, for surface treatments such as etching, ALD, and ALE, which are affected by the presence of patterns and the direction of gas molecule supply, multiple gas supply systems to the chamber are provided symmetrically around the stage, not just the exhaust system. The primary supply gas system and the exhaust system are controlled to be diagonally opposite the stage, and the gas is controlled to traverse the stage. In addition, the gas is made to swirl around the stage. This ensures that gas flows from all directions onto the workpiece surface on the stage, preventing the creation of areas with poor supply (areas with infrequent supply).

[0028] For lateral exhaust, multiple exhaust ports are provided at a position higher than the workpiece transport level in the chamber, and these are divided into four rectangular sections, with the exhaust flowing through four vertical holes on the side of the stage. Each section is equipped with a pressure regulating valve, and these are integrated on the side of the stage in a manner similar to a tournament bracket. This allows the chambers to be arranged even in cluster-type equipment layouts without becoming misaligned. [Effects of the Invention]

[0029] According to one embodiment of the pressure control method and surface treatment apparatus, malfunctions caused by gas supply can be avoided, the yield rate of good products can be improved, and the mass production of defective products can be avoided. Furthermore, since exhaust piping can be collected around the stage and discharged from the bottom of the chamber, the arrangement of the exhaust system of a cluster-type apparatus can be standardized regardless of the exhaust means (TMP+DP or DP). Unstable gas flow in the intermediate flow region can also be detected and corrected by the pressure gauge of each exhaust pipe. In addition, the incident direction of gas molecules caused by gas flow can be controlled by the pressure regulating valve, so surface treatments that obtain suitable performance independent of gas injection, such as etching, ALD, and ALE, can be performed. [Brief explanation of the drawing]

[0030] [Figure 1] Figure 1 shows an example of the configuration of equipment in a surface treatment apparatus, including a supply gas valve. [Figure 2a] Figure 2a is a schematic longitudinal cross-sectional view of a surface treatment apparatus having multiple exhaust paths according to an embodiment. [Figure 2b] Figure 2b is a three-dimensional schematic diagram with a portion cut out for illustrative purposes. [Figure 2c] Figure 2c is a cross-sectional view AA of Figure 2a, showing the operation of the rotor blade. [Figure 3] Figure 3 is a schematic diagram relating to another embodiment, showing the shape of the rotor blades for pressure adjustment and the position of the rotor blades at different opening angles. [Figure 4a] Figure 4a relates to another embodiment and shows the shape, position, and configuration of the rotor blades for pressure adjustment, and shows the rotor blades in the fully open state. [Figure 4b] Figure 4b relates to another embodiment and shows the shape, position, and configuration of the rotor blades for pressure adjustment, and shows the state when the rotor blades are fully closed. [Figure 5a] Figure 5a is a schematic longitudinal cross-sectional view of a surface treatment apparatus having a single exhaust path according to another embodiment. [Figure 5b] Figure 5b shows the rotor blades in Figure 5a at their fully open position. [Figure 5c]Figure 5c shows the fully closed position of the rotor blades in Figure 5a. [Figure 6a] Figure 6a relates to another embodiment and shows the shape, installation position, and configuration of the rotor blades for pressure adjustment, showing the state when the rotor blades are fully closed. [Figure 6b] Figure 6b is a cross-sectional view of the rotor blade as seen from the EE direction in Figure 6a. [Figure 7a] Figure 7a is a schematic longitudinal cross-sectional view relating to another embodiment, showing the position and configuration of the rotor blades for pressure adjustment. [Figure 7b] Figure 7b shows the rotor blades in Figure 7a when fully extended. [Figure 7c] Figure 7c shows the rotor blades in Figure 7a when fully closed. [Figure 8a] Figure 8a is a schematic longitudinal cross-sectional view of a surface treatment apparatus having an exhaust path in the lateral direction, relating to another embodiment. [Figure 8b] Figure 8b is a cross-sectional view of the exhaust passage shown in Figure 8a. [Figure 8c] Figure 8c is a schematic diagram showing the configuration of the exhaust path in Figure 8a. [Figure 8d] Figure 8d is a schematic diagram showing other configurations of the exhaust path in Figure 8a. [Modes for carrying out the invention]

[0031] Examples and embodiments will be described below with reference to the drawings. However, in the following description, the same reference numerals will be used for the same components, and repeated descriptions may be omitted. In addition, the drawings may be more schematic than the actual embodiments in order to make the explanation clearer, but they are merely examples and do not limit the interpretation of the present invention.

[0032] This invention describes the gas flow and gas flow path of a surface treatment apparatus, which is the subject of this invention, and a method for controlling them. Figure 1 shows an example of a surface treatment apparatus. This surface treatment apparatus 110 is a process apparatus (which performs gas treatment; the entire apparatus is not shown) and is shown schematically. A stage 2 on which a workpiece 1 is mounted is housed inside a chamber (reactor, etc.) 3 that is isolated from the atmosphere, where gas etching, film deposition, etc., are performed. Gas dispersion chambers (sub-chambers) 4a, 4b, and 4c are provided above the chamber 3 facing the stage 2. These gas dispersion chambers 4a, 4b, and 4c are made up of spacers 6a, 6b, and 6c, gas dispersion plates 7a and 7b, and a shower plate 8, forming the upper chamber structure 5. In this embodiment, the upper chamber structure 5 is mainly responsible for supplying gas, but it may also be a chamber upper structure that has a high-frequency application means, a heating means, or a means for measuring film thickness, temperature, etc., either individually or in combination with multiple such means. In this embodiment, a halogen lamp 10 is installed on the atmospheric side as a source of visible to infrared light, orbiting the upper chamber structure 5, and the generated light can be irradiated into the chamber 3, including the workpiece 1, through the transmissive window 11. A gate valve 15 for loading and unloading the workpiece 1 is attached to the end of the side wall of the chamber opening 3a.

[0033] Inside chamber 3, directly below stage 2, are the main valve 22 and exhaust port 18. Below these, directly above the turbomolecular pump (TMP) 23, is a pressure regulating valve 21 for adjusting the pressure inside chamber 3. The turbomolecular pump (TMP) 23 uses a composite vane shape that allows for a relatively high intake pressure at the inlet. The gas from the exhaust port of the turbomolecular pump (TMP) 23 is exhausted by a dry pump 26 through exhaust pipes 20a and 20b, and then transported through exhaust pipe 27 to the building's exhaust gas treatment device (not shown). The pressure in chamber 3 and the pressure in exhaust pipe 20a are monitored by diaphragm pressure gauges 28 and 29, respectively.

[0034] The gas box (MFC Unit) 30 in Figure 1 is a component unit consisting of multiple gas flow controllers (not shown), multiple solenoid valves that control the opening and closing of air-operated valves, a gas leak detection function, a function to exhaust the housing through a duct in the event of a gas leak, and a function and components to constantly monitor the negative pressure (indicating exhaust) inside the gas box 30. Gases from multiple gas sources are introduced into the gas box 30 in Figure 1, the flow rate of each gas is controlled, and a mixed gas is formed as needed before being sent to the chamber 3 and exhaust pipe 20a. Basically, by controlling the flow so that one of the gases, including an inert gas, is always flowing during processing, the gas that flows from the final discharge valve G1E to the exhaust system does not flow back into the chamber 3 and does not contribute to the processing reaction of the workpiece 1.

[0035] In this embodiment, only one gas line was used for the process gas line and the exhaust gas line. However, in the surface treatment apparatus 110, multiple gas piping systems may be connected according to their respective purposes. Systems may be separated based on the properties of the gas (flammable, oxidizing, and spontaneously combusting), or systems may be separated by application, such as dedicated gas lines for purging and venting.

[0036] A transport chamber 24, which houses a hand (end effector) 25 and its drive mechanism (not shown) for loading the workpiece 1 into and out of the chamber 3, is connected to the chamber 3 via a gate valve 15. Several other chambers are connected by the transport chamber 24, forming a cluster-type surface treatment apparatus 110. In other words, the surface treatment apparatus 110 has a sample stage 2 on which the workpiece 1 is mounted when surface treating the workpiece 1 in a treatment chamber 3 isolated from the atmosphere. During the process, process gas is supplied to the workpiece 1 on the sample stage 2, and the gas in the treatment chamber 3 is discharged from around the sample stage 2.

[0037] Next, the process procedure in this embodiment will be described. In a vacuum or purged environment, the gate valve 15 is opened and the workpiece 1 mounted on the hand 25 is transferred to the upper surface of the stage 2. In many cases, the workpiece 1 is received by the tips of multiple lift pins (not shown) that are incorporated into the stage 2 and can move up and down relative to each other, and then transferred onto the stage. After closing the gate valve 15, the surface treatment begins. The temperature of the workpiece 1 is adjusted, the gas pressure is adjusted, and then, if necessary, surface treatments such as external surface heating, gas plasma generation, physicochemical attack and adhesion by ion attraction, and diffusion are performed. After the treatment, the gas in the chamber 3 is exhausted or purged to clean it, and then, in a vacuum or purged environment again, the gate valve 15 is opened and the treated workpiece 1 is transferred to the hand 25 and collected in the transport chamber 24. By repeating this process in multiple chambers, multiple different surface treatments can be applied to the workpiece 1. Furthermore, by processing multiple workpieces of the same type within the same processing lot in multiple chambers of the same specifications, the number of pieces processed per unit time can be increased, thereby increasing productivity.

[0038] In conventional cluster-type processing chambers, including the cluster-type surface treatment apparatus 110 shown in Figure 1, the pressure in the chamber 3 is adjusted by driving the pressure regulating valve 21 based on the value of a pressure gauge 28 that measures the chamber pressure, so that the desired pressure is obtained. Conventionally, the workpiece 1 and the pressure regulating valve 21 have been arranged coaxially to prevent exhaust eccentricity, but this has not always been well controlled. There is a bias in the opening shape of the rotor blades of the pressure regulating valve 21 in the direction in which they open. Also, the opening of the turbomolecular pump (TMP) 23 is basically circular, and it has blades around the periphery, resulting in a characteristic where the exhaust velocity is higher at the periphery, so there is also a bias in the exhaust velocity on the exhaust surface of the turbomolecular pump (TMP) 23. Furthermore, there is a problem that the gas flow, the direction and amount of exhaust gas flow, and the flow velocity change when the opening degree of the pressure regulating valve is different. Due to these factors, exhaust eccentricity relative to the workpiece 1 inevitably occurred. Furthermore, the presence of the main valve drive shaft 22a, the stage introduction section 2a supporting stage 2, the asymmetry of the internal shape of chamber 3, the inclination of the mounting surface of stage 2, and the deformation of the workpiece all result in uneven exhaust resistance. This, combined with subtle differences in the circumferential direction and the viscosity of the gas, causes exhaust eccentricity where the gas flow differs in the circumferential direction. 2w is the workpiece mounting surface of the stage.

[0039] Figure 2a shows a schematic longitudinal cross-sectional view of a surface treatment apparatus according to one embodiment. Figure 2a is a schematic longitudinal cross-sectional view of a surface treatment apparatus having multiple exhaust paths according to the embodiment. Susceptors 2c are arranged around the workpiece mounting surface of stage 2. The stage introduction section 2b, and the piping, wires, and signal lines housed inside stage 2 have been omitted. These are used for temperature control of the workpiece 1 and as high-frequency waveguides for ion drawing. The drive mechanism for the lift pin (not shown) has also been omitted.

[0040] Although the surface treatment apparatus 110 in Figure 1 is described as a process apparatus that activates the gas and promotes the reaction by supplying thermal energy to the workpiece 1 with a halogen lamp 10, even if other gas excitation means are used, such as plasma generated by a high-frequency power supply or heating the gas dispersion chamber 4 to form an activated gas beforehand and blowing it onto the workpiece 1, the configuration of the process gas supply device and the gas control method remain the same as in this embodiment, although the timing of excitation for processing may differ. Measuring instruments such as optical instruments for measuring film thickness and the progress of processing may also be incorporated.

[0041] Furthermore, regarding the exhaust means 31 from the chamber 3, in this embodiment, exhaust was performed using a turbomolecular pump (TMP) 23 and an auxiliary dry pump (not shown). However, the exhaust may be guided from the space at the bottom of the chamber 3 through a large-diameter exhaust pipe (not shown) to a large dry pump (not shown), and the dry pump alone may be used as a process processing apparatus with a large exhaust capacity. Also, using other exhaust means such as a mechanical booster pump does not change the basic gas control method and control device of this embodiment in any way.

[0042] Figures 2a and 2b illustrate an embodiment of a surface treatment apparatus that can be incorporated into the same cluster-type surface treatment apparatus as the surface treatment apparatus 110 described in Figure 1. Figure 2a is a schematic longitudinal cross-sectional view, and Figure 2b is a schematic stereoscopic perspective view with a portion of the parts of Figure 2a cut out. The upper chamber structure 5 is equipped with a gas supply unit as in Figure 1, but also has other functions for performing surface treatment, such as a high-frequency application means. Furthermore, details of parts such as the lift pin drive mechanism inside the stage 2, the electrostatic chuck function, part of the vacuum sealing member, the high-frequency application function for ion attraction, and small bolts and nuts have been omitted.

[0043] 51 is an exhaust plate, and in this embodiment, six exhaust holes 52, which serve as exhaust ports, are provided at equal intervals around the outer circumference of the stage 2. 55 is a partition plate, which is a set of six plates inserted into grooves provided in the side walls of the stage and exhaust mounting base 64 and the side wall of the stage 2, in order to divide the cylindrical space between the outside of the stage 2 and the stage and exhaust mounting base 64 into six sections in the circumferential direction. One exhaust hole 52 is positioned above each exhaust path separated by the partition plate 55. In this embodiment, the space is divided into six locations, but it is not a problem to increase or decrease the number of divided spaces (e.g., 3 to 16 locations) depending on the size of the workpiece 1, the exhaust volume, and the number of control systems, or to control multiple spaces together as a group. Below the stage 2, a rotational force drive and introduction device 56 is provided. Basically, it has a rotational drive mechanism (motor, swivel air cylinder, etc.), a reduction gear (harmonic gear, etc.) as needed, and a sealing mechanism between the atmosphere and the vacuum. Pressure gauges 68 are installed in the middle of each of the six fan-shaped vertical spaces, which are divided into six sections by partition plates 55. The number of sections may be reduced to three, and two spaces may be controlled together. 65 is a TMP base for mounting a turbomolecular pump (TMP) 23, and 66 is the rotation and vertical movement mechanism for the TMP base 65.

[0044] The swivel plate (rotating blade) 62 is attached to the tip of the rotational force drive and introduction device 56 and can swivel (rotate) across the space between the side wall of the stage 2 and the stage and exhaust mounting base 64. In other words, the rotational force drive and introduction device 56, which is the power device for driving the swivel plate (rotating blade) 62, which is the pressure regulating valve 21, is housed within the structure of the sample stage 2. An upper opening plate 58 is attached to the bottom of the stage 2, and an upper opening (upper opening) 59 is provided in the upper opening plate 58. A lower opening plate 60 is located in close contact with the periphery of the upper opening plate 58, and a lower opening (lower opening) 61 is provided in the lower opening plate 60. A space for the swivel plate 62 to swivel is provided between the upper opening plate 58 and the lower opening plate 60. In other words, the swivel plate (rotating blade) 62, which is the pressure control valve (pressure regulating valve 21), has an exhaust path corresponding to the exhaust port 52 and is located on the outer circumference of the sample stage 2 on which the sample is placed. Then, the rotation direction of the rotor blade 62 of the pressure regulating valve is shielded from the opening 61 so as to be approximately perpendicular to the direction of gas flow from upstream to downstream in the exhaust path. In this embodiment, the upper opening 59 and the lower opening 61 are made of the same shape, but there is no problem if they are made of different shapes. Also, there is no problem if only one of the upper opening plate 58 or the lower opening plate 60 is provided.

[0045] The upper opening plate 58 is assembled to the bottom surface 2z of the stage, and the lower opening plate 60 is assembled after the rotating plate 62 is attached. The rotating space of the rotating plate 62 is thin and is in close contact with the upper opening 59 and the lower opening 61, so the exhaust resistance is large (exhaust conductance is small) and it has sufficient gas shielding capacity.

[0046] Figure 2c is a plan view as seen from AA in Figure 2a. In Figure 2c, the upper diagram is a hatched diagram, and the lower diagram is the upper diagram with the hatching removed. In this embodiment, the space around stage 2 is divided into six sections, and these six sections are formed by insertable partition plates 55, which are also inserted into the upper opening plate 58. The swivel plate 62 can be retracted to directly below the stage 2, and the swivel plate 62 can also be shielded across the space between the upper opening 59 and the lower opening 60. In other words, when the rotor blade (swivel plate 62), which is a pressure regulating valve, is fully opened, the rotor blade of the pressure regulating valve can be retracted to a position that does not obstruct the gas flow within the bottom surface of the lower part of the structure of the sample stage 2. For this reason, unlike the surrounding area, the lower half of the upper opening plate 58 is counterbore in a shape not shown in the cross-section of the figure, and this counterbore is used as the space in which the swivel plate 62 moves.

[0047] Figure 2c shows the state where the opening degree of each of the six swivel plates 62 in the exhaust space is different. Around the outside of Figure 2c, the rotation angle and opening degree [%] of each swivel plate 62 are shown.

[0048] The pressure control method of this embodiment will be explained using Figures 2a, 2b, and 2c. First, we will describe the case where the workpiece 1 mounted on the upper surface of the stage 2 is exhausted evenly from the periphery. When processing of the workpiece 1 begins, process gas is supplied to the chamber 3 at a control value set in the processing recipe or a flow rate calculated by AI. The opening of the swivel plate 62 is controlled so that each pressure gauge 68 installed in each exhaust space shows basically the same pressure. Each of the exhaust holes 52 provided in the exhaust plate 51 is opened with the same opening shape and area, and if the vacuum pressure shown by each pressure gauge 68 is the same, the gas flow rate drawn in from each exhaust hole 52 is basically the same. In short, the opening of the swivel plate 62 is feedback controlled based on the vacuum level shown by each pressure gauge 68. Of course, the control pressure value may be slightly changed by calculating with AI, taking into account the presence of the stage introduction section 2b, etc. By controlling in this way, it is possible to exhaust gas with a uniform gas flow rate from the periphery of the workpiece 1. In other words, by providing multiple process gas outlets above the workpiece 1, approximately opposite the workpiece 1, and controlling whether or not to allow the process gas to flow, or varying the gas flow rate, and further controlling this in conjunction with the control of a pressure regulating valve (swivel plate 62), the gas flow direction can be controlled to ensure that the process gas flows evenly and horizontally over time to the workpiece surface within the workpiece 1.

[0049] Next, a control method for increasing the process gas flow rate in a certain direction within the processing surface of the workpiece 1 will be explained. Such control is used to correct in-plane defects that occurred in the previous process. For example, when forming an insulating film of a multilayer film, if non-uniformity of in-plane film deposition is found in the film deposition in a separate device or chamber in the previous process and it is desired to correct it, or when performing surface reactions of etching a multilayer film, if the amount of material removed in a direction differs within the surface of the workpiece 1 in the previous process, it is necessary to correct this in the chamber. Basically, the gas passage holes formed by the opening of the upper opening 59, lower opening 61 and the swivel plate 62 corresponding to the exhaust space in which more gas is to be drawn in are enlarged relative to the vacuum value indicated by each pressure gauge 68, and the pressure gauge 68 is controlled to be lower than the vacuum level indicated by the other pressure gauges 68, thereby varying the gas flow rate into the exhaust space and making it greater than that of the other exhaust spaces. Naturally, the direction and flow rate of the gas flowing over the workpiece 1 also change. Needless to say, the degree of correction can be controlled by increasing or decreasing the difference in the controlled vacuum value, or by changing the control time interval, depending on the degree and extent of the correction.

[0050] Furthermore, this paper describes a control method for surface treatment of a workpiece 1 by varying the gas flow rate using a swirling flow. In the latest miniaturization of the semiconductor industry, the processing speed is often reduced from conventional speeds to a few tens of nanometers per minute, and sometimes to a few nanometers. This is to control the processing with higher precision. In addition, for processes affected by the direction of process gas supply or the flow of products after the reaction, it is necessary to eliminate or average out the effects of these flows. In such control cases, the opening degree of each swirling plate 62 can be changed programmatically or by calculation using AI control to change the gas flow rate and direction flowing over the workpiece 1. Since the processing speed is reduced, the opening degree of the swirling plate 62 can be changed mechanically to symmetrically swirl the gas flow around the workpiece 1 or to flow randomly. Furthermore, the process gas outlet of the upper chamber structure 5 may be divided into six sections corresponding to the exhaust spaces, and each section may be placed above the workpiece 1 on the symmetrical side, so that the process gas is exhausted only from the exhaust space on the opposite side of the position where it flows into the chamber 3. If this is repeated for six different positions, the gas flow direction of the workpiece 1 and the resulting difference in incident molecules can be mitigated. In particular, the effect of gas incidence on shadowed areas caused by the presence of fine patterns (micro-shadowing phenomenon) can be reduced. In this case, the temporal change in the vacuum value measured by the pressure gauge 68 may be used as a means to determine whether the flow rate control is working properly.

[0051] Next, another embodiment will be described using Figure 3. Figure 3 is a schematic diagram relating to another embodiment, showing the shape of the rotor blades for pressure adjustment and the position of the rotor blades at each opening. In Figure 3, the upper diagram is a hatched diagram, and the lower diagram is the upper diagram with the hatching removed. The embodiment in Figure 3 is a view looking upward from the TMP base 65 in Figure 2a (that is, upward at the height of B shown in Figure 2a). Unlike in Figures 2a-2c, where the exhaust space is divided into six by partition plates 55, the stage and exhaust mounting base 64' in Figure 3 have 12 exhaust cylinders 57 on the outer circumference of the stage 2 to form the exhaust space. An exhaust plate 51 (not shown) having exhaust holes 52 for drawing in gas from the chamber 3 may be provided on the upper part of the exhaust cylinders 57, similar to Figures 2a-2c. In short, there is no change in the fact that exhaust ports are provided axially symmetric to the workpiece 1. The rotary drive shaft from the rotary drive device 56' is positioned perpendicular to the hole in the exhaust cylinder 57. Twelve flap swivel plates (rotating blades) 62f, slightly smaller in diameter than the exhaust cylinder 57, are attached to the rotary drive shaft to form a so-called flapper-type pressure control valve (also called a pressure regulating valve) inside the exhaust cylinder 57. The blade surfaces of the pressure regulating valve's rotating blades 62f are designed to rotate approximately 90 degrees in the direction of the gas flow from upstream to downstream in the exhaust path, from a position where they coincide (fully open) to a position where they are vertical and shielding (fully closed). A pressure gauge 68 may be provided above the pressure control valve in the exhaust cylinder 57 (towards the back of the page), as in Figures 2a-2c. In other words, the exhaust cylinder 57, which serves as an exhaust port, and the flap swivel plates (rotating blades) 62f, which serve as a pressure control valve (pressure regulating valve) and have an exhaust path corresponding to the exhaust cylinder 57, are arranged within the exhaust path. Figure 3 schematically shows the rotational positions of the flap rotors 62f in fully closed, 15° open, 30° open, 45° open, 60° open, 75° open, and fully open positions using 12 flap rotors (rotating blades) 62f.

[0052] The pressure control method in Figure 3 can also be controlled in the same way as in Figures 2a-2c.

[0053] Figures 4a and 4b show other embodiments. Figure 4a relates to another embodiment and shows the shape, position, and configuration of the rotor blades for pressure adjustment, showing the state when the rotor blades are fully open. Figure 4b relates to another embodiment and shows the shape, position, and configuration of the rotor blades for pressure adjustment, showing the state when the rotor blades are fully closed. Figure 4a shows the state in which all 12 flap swivel plates 62f1 are open, and Figure 4b shows the state in which all 12 flap swivel plates 62f1 are closed. In the height direction, Figures 4a and 4b are views from above at the height B shown, from the TMP base 65 in Figure 2a, similar to Figure 3. 2z is the bottom surface of the stage 2, and openings 63 are provided around it. There are 12 openings 63, and they are not cylindrical in shape as shown in Figure 3. The stage and exhaust mounting base 64o in Figure 4 are larger than the diameter of the upper mounting flange of the turbomolecular pump (TMP) (not shown), and the flap swivel plate 62f1 can be retracted to the larger outer circumference. In other words, the flap swivel plate (rotating blade) 62f1, which serves as a pressure control valve (pressure regulating valve) and has an exhaust path corresponding to the opening 63, is located on the outer circumference of the sample stage 2 on which the sample is placed. The shape was designed to open up an effective exhaust space between the bottom surface 2z of the stage and the diameter of the upper mounting flange of the turbomolecular pump (TMP) (not shown) over the largest possible area. The openings 63 are separated from each other by a space on the far side of the paper, and an exhaust plate (not shown) with an exhaust hole for drawing in gas from the chamber 3 may be provided above the openings 63, as in Figures 2a-2c. Also, a pressure gauge 68 may be provided above the pressure control valve of the opening 63 (far side of the paper), as in Figures 2a-2c. The flap swivel plate 62f1 is structured to be able to swivel around the axis of the pivot point 69, and is designed to swivel in contact with the rotary drive unit 56a. Needless to say, in order to rotate the rotary drive unit 56a and the stage and exhaust unit mounting base 64o through the flange surface from the atmospheric pressure side on the back side, it has a rotary drive mechanism (motor, swivel-type air cylinder, etc.), a reduction gear (harmonic gear, etc.) if necessary, and a sealing mechanism between the atmosphere and the vacuum.In other words, the rotary drive unit 56a, which is the power device for driving the rotation of the pressure regulating valve, is located on the outside atmospheric side of the exhaust path at the bottom of the processing chamber 2. Furthermore, although the rotary drive unit 56a is shown in direct contact with the outer circumference of the flap rotation plate 62f1, a link-type method for rotating the flap rotation plate 62f1 is also acceptable.

[0054] The pressure control method shown in Figures 4a and 4b can also be controlled in the same way as in Figures 2a and 2c.

[0055] Figures 5a and 5c show a pressure control unit illustrating another embodiment of the present invention. Figure 5a is a schematic longitudinal cross-sectional view of a surface treatment apparatus having a single exhaust path according to another embodiment. Figure 5b shows the fully open position of the rotor blade in Figure 5a. Figure 5c shows the fully closed position of the rotor blade in Figure 5a. The difference from the embodiments of the present invention described above is that the cylindrical space around the workpiece 1 is a common exhaust path, but multiple pressure control valves are provided on the lower side of the stage 2 of the stage and exhaust section mounting base 64i. The substantially cylindrical space between the sample stage 2 and the side wall of the processing chamber 3 is used as a common exhaust path, and 12 flap swivel plates 62f2, which are multiple independently controlled pressure regulating valves, are provided circumferentially at the lower part of the structure of the sample stage 2. Another difference is that the rotor blade and other swivel blades in the direction of rotation overlap sequentially in the vertical direction. In other words, the rotor blades (12 flap swivel plates 62f2) of the pressure regulating valves are configured to partially overlap in the direction of gas flow, without interfering with each other, and allowing for independent opening settings. Figure 5a is a schematic longitudinal section view, and Figures 5b and 5c are plan views looking upward from the CC shown in Figure 5a. Figure 5b shows the state where all 12 flap swivel plates 62f2 are open (opening degree 60°), while Figures 5a and 5c show the state where all 12 flap swivel plates 62f2 are closed (resisting the gas flow: opening degree 0°). As shown in Figure 5b, when fully open, the swivel plates 62f2 can be retracted to the underside of the stage bottom surface 2z. The swivel plates 62f2 are also attached to the vacuum-side tip of the rotational force drive and introduction device 56i, and are shaped to gradually droop with distance from the mounting position. This prevents adjacent swivel plates 62f2 from interfering with each other when they overlap in the vertical direction. In other words, the sample stage 2 on which the sample is placed has an exhaust path arranged around its outer circumference, and a swivel plate 62f2, which serves as a pressure control valve (pressure regulating valve), is located within the exhaust path. Although not shown, a pressure gauge 68 may be installed in the same way as shown in Figure 2a. Note that, to avoid cluttering the diagram, only one of the 12 swivel plates 62f2 is labeled, but the rest are configured similarly.

[0056] Furthermore, multiple gas pipes 71 may be connected to the stage and exhaust mounting base 64i. Upstream of these gas pipes 71, a final-stage gas supply valve 73, a flow rate controller (not shown), etc., are installed, allowing noble gases such as argon (Ar) or inert gases such as nitrogen (N2) or carbon dioxide (CO2) to flow as single gases or mixed gases. In other words, a function (71, 73, flow rate controller, etc.) is provided to allow gas (noble gases such as argon (Ar) or inert gases such as nitrogen (N2) or carbon dioxide (CO2) to flow as single gases or mixed gases) to flow separately and independently into the exhaust path downstream of the workpiece 1 in the processing chamber 3, unlike the outflow of process gas. It is also possible to change the exhaust of gas around the workpiece 1 by deciding whether or not to flow that gas, or by varying the gas flow rate of that gas.

[0057] The pressure control shown in Figures 5a-5c will now be explained. Each rotational force drive and introduction device 56i can independently control the opening degree of the flap swivel plate 62f2. The rotational force drive and introduction device 56i control the opening degree of the flap swivel plate 62f2 by program control or AI control. This makes it possible to exhaust gas with a uniform gas flow around the workpiece 1, eccentric exhaust, or programmatically or randomly change the gas flow.

[0058] Furthermore, during the processing of the workpiece 1, the opening and closing of multiple gas supply valves 73 upstream of each gas pipe 71, or the gas flow rate of a flow controller (not shown), are controlled by program or AI while maintaining a constant gas flow rate from all gas pipes 71. The pressure in the chamber 3 near the workpiece 1 is determined by the gas conductance, which is determined by the gas flow rate of the process gas from the gas supply section of the opposing chamber upper structure 5, the gas flow rate from this gas pipe 71, and the opening degree of the swivel plate 62f2 in Figures 5a-5c, as well as the gas conductance of the pump (turbomolecular pump (TMP) 23 or dry pump 26') and the exhaust pipes in the exhaust path. However, by closing the gas supply valves 73 of the other gas pipes 71, for example, leaving one open, the gas supply is cut off, and gas is supplied from only one location. As a result, the discharge of process gas supplied to the workpiece 1 is weakened, and eccentric exhaust of process gas from the workpiece 1 can be achieved. This can be used to control the discharge of process gas, the direction of gas flow to the workpiece 1, and the gas flow rate.

[0059] Next, other embodiments of the present invention will be described using Figures 6a and 6b. Figure 6a relates to another embodiment and shows the shape, installation position, and configuration of the rotor blade for pressure adjustment, showing the rotor blade in the fully closed state. Figure 6b is a cross-sectional view of the rotor blade as seen from the EE direction in Figure 6a. In Figure 6a, the upper view is a hatched view, and the lower view is the upper view with the hatching removed. Figure 6a is a view looking upward from the TMP base 65 of Figure 5a, at a height D shown. As in the case of Figure 5a, the exhaust space is common around the entire perimeter of the stage 2 on which the workpiece 1 is mounted. In Figure 5a, the rotational force drive and introduction equipment 56i was mounted to rotate at the bottom of the stage 2, but in Figure 6a, it is mounted on the side of the stage 2. 79 is the rotation drive shaft. The fan-shaped flap rotation plates (rotor blades) 62f3 attached to the rotation drive shaft 79 do not overlap with adjacent flap rotation plates 62f3. Figure 6a shows the position of the flap swivel plate 62f3 when fully closed (opening 0°). Figure 6b shows a diagram including a cross-section of the flap swivel plate 62f3 as seen from the EE direction shown in Figure 6a. The swivel range of the flap swivel plate 62f3 is indicated by arrows. The outer peripheral support ring 77 is fitted inside the stage and the exhaust section mounting base 64f, but a protrusion is provided to reduce the gap that occurs when the flap swivel plate 62f3 is fully closed and horizontal, thereby increasing the exhaust resistance. In other words, there is an exhaust path arranged on the outer circumference of the sample stage 2 on which the sample is placed, and the flap swivel plate 62f3, which is a pressure control valve (pressure regulating valve), is located within the exhaust path.

[0060] The pressure control method in the embodiments shown in Figures 6a and 6b is the same as the control method in Figures 5a-5c, and pressure control and gas flow control can be performed in the same way.

[0061] Next, other embodiments of the present invention will be described using Figures 7a, 7b, and 7c. Figure 7a is a schematic longitudinal cross-sectional view relating to another embodiment, showing the position and configuration of the rotor blades for pressure adjustment. Figure 7b shows the rotor blades of Figure 7a in the fully open position. Figure 7c shows the rotor blades of Figure 7a in the fully closed position. Figure 7a is a schematic longitudinal cross-sectional view, but differs from the embodiments in Figures 5a to 5c in that the rotational force drive and introduction equipment 56o is attached to the atmospheric-side flange of the stage and exhaust section mounting base 56o, rather than inside the stage 2, and the flap swivel plate 62f4 attached to the tip retracts to the outside of the exhaust path, rather than to the bottom of the stage 2, when fully open. The power equipment 56o for driving the swivel of the flap swivel plate 62f4, which is a pressure adjustment valve, is configured to circulate on the atmospheric side outside the exhaust path at the bottom of the processing chamber. Figures 7b and 7c are plan views looking upward from the FF shown in Figure 7a. Figure 7b shows the state where all 12 flap swivel plates 62f4 are open (opening angle 30°), while Figures 7a and 7c show the state where all 12 flap swivel plates 62f4 are closed (resisting gas flow: opening angle 0°). The 12 flap swivel plates 62f4 hang down towards the tip so as not to interfere with each other. Although not shown, a pressure gauge 68 may be installed in the same way as shown in Figure 2a. Note that, to avoid cluttering the diagram, only one of the 12 flap swivel plates 62f4 is labeled, but the rest are configured similarly. In other words, there is an exhaust path arranged around the outer circumference of the sample stage 2 on which the sample is placed, and the flap swivel plates 62f4, which serve as pressure control valves (pressure regulating valves), are located within the exhaust path.

[0062] The pressure control method in the embodiments shown in Figures 7a, 7b, and 7c is the same as the control method in Figures 5a to 5c, and pressure control and gas flow control can be performed in the same way.

[0063] Figures 8a, 8b, 8c, and 8d illustrate other embodiments of the present invention. Figure 8a is a schematic longitudinal cross-sectional view of a surface treatment apparatus having a lateral exhaust path, relating to another embodiment. Figure 8b is a cross-sectional view of the exhaust path in Figure 8a. In Figure 8b, the upper view is a hatched view, and the lower view is the upper view with the hatching removed. Figure 8c is a schematic diagram showing the configuration of the exhaust path in Figure 8a. Figure 8d is a schematic diagram showing another configuration of the exhaust path in Figure 8a. Figure 8a is a schematic longitudinal cross-sectional view cut along the line indicated by GOH in Figure 8b. The mounting frame, the internal contents of the chamber upper structure 5, and the internal contents of stage 2' are not shown. Also omitted are the sealing material for vacuum, the structure for mounting it, and small bolts and nuts. Stage 2' can be raised and lowered inside chamber 3'. The details of the lifting mechanism 2m are also omitted. The GO cross section (left half) of Figure 8a shows the state when the workpiece has been loaded (or just before unloading), with the workpiece 1 supported above the upper surface 2y of the stage 2' by the stage lift pin 2p. During the process, as shown in the OH cross section (right half), the stage 2' rises together with the shield 101 installed on the outer circumference of the stage 2', forming a small chamber space 3b. Next, the gas discharge path will be explained. The gas supplied from the stage upper structure 5 reaches this small chamber space 3b, and the workpiece 1 is processed. After processing, the gas is discharged through an exhaust ring 91 provided on the inner wall of the processing chamber 3, and through multiple exhaust holes 92 provided in the exhaust ring 91 to the corresponding circumferential exhaust passages 93. Since the multiple circumferential exhaust passages 93 are separated in four places by spacers 100, the gas flowing in from two exhaust holes 92 at each location does not mix with the gas from the other exhaust holes 92. The gas in one circumferential exhaust passage 93 is discharged through the square of chamber 3' into a corresponding lateral exhaust passage 94 connected to the circumferential exhaust passage 93, and then into a corresponding vertical exhaust passage 95. A pressure regulating valve 98 is attached to an exhaust flange 97 mounted on chamber 3', and an exhaust pipe 99 is attached downstream of it. A vacuum gauge 96 is inserted from the corner side at the intersection of the lateral exhaust passage 94 and the vertical exhaust passage 95.In other words, the sample stage 2' on which the sample is placed has an exhaust path (multiple exhaust holes 92, multiple circumferential exhaust passages 93, multiple lateral exhaust passages 94, multiple vertical exhaust passages 95, multiple discharge flanges 97, and multiple discharge pipes 99) arranged on its outer circumference, and a pressure regulating valve 98 is located within the exhaust path. Furthermore, an exhaust port (exhaust hole 92) is provided on the inner wall of the processing chamber 3 on the side of the workpiece 1 during process processing, and multiple exhaust paths (vertical exhaust passages 95) are provided that penetrate the processing chamber 3 vertically from the exhaust port, with a pressure regulating valve 98 that can be independently controlled placed in each exhaust path (vertical exhaust passage 95).

[0064] The subsequent gas discharge path is explained in Figure 8c. In Figure 8a, the inlets of the vertical exhaust passage 95 are marked with points E1 to E4. Figure 8c schematically shows the subsequent exhaust. The pressure regulating valve 98 is attached to the square discharge flange 97 on the lower surface of the chamber 3'. Downstream of the pressure regulating valve 98, E1 and E2 on the right side and E3 and E4 on the left side are integrated when viewed from the opposite inlet of the chamber 3'. In this embodiment, the pipes E1 to E4 were integrated with a pipe having twice the cross-sectional area of ​​the inner cross-sectional area of ​​the pipes. Further downstream, the two exhaust pipes integrated on the left and right sides were further integrated into one. The inner cross-sectional area of ​​this exhaust pipe was made twice the cross-sectional area, that is, the same as the sum of the inner cross-sectional areas of E1 to E4.

[0065] Unlike Figure 8c, Figure 8d shows an exhaust chamber 102 with four pressure regulating valves 98 evenly spaced near it, and exhaust piping connected from each pressure regulating valve 98 to multiple discharge flanges 97 at the bottom of chamber 3'. This exhaust system configuration provides more layout flexibility when the equipment placement at the bottom of chamber 3' is crowded.

[0066] Even when exhausting laterally as shown in Figures 8a, 8b, 8c, and 8d, the pressure control method can be controlled in the same way as in Figures 2a-2c. It is possible to exhaust uniformly in the circumferential direction from the workpiece 1, or to exhaust eccentrically in a programmable or AI-controlled manner. As in Figures 2a-2c, the outlet position of the gas supplied from the stage upper structure 5 may be controlled to be approximately diagonally opposite to the direction of exhaust, thereby evenly changing the gas flow direction and flow rate from the workpiece 1. Furthermore, instead of providing a pressure gauge 96, a simple flanged spacer for sealing can be used, and predictive control can be performed without measuring the pressure. Moreover, the objectives of the present invention can be achieved even if the number and shape of the exhaust holes 92, the type and mounting position of the pressure regulating valve are changed.

[0067] The present invention has been described in detail above based on examples and embodiments, but it goes without saying that the present invention is not limited to the above examples and embodiments and can be modified in various ways. [Explanation of symbols]

[0068] 1: Workpiece 2, 2': Stage 2a, 2b: Stage introduction 2c: Susceptor 2m: Lifting mechanism 2p: Stage lift pin 2w: Workpiece mounting surface of the stage 2y: Top of the stage 2z: Stage bottom 3, 3': Chamber 3a: Chamber opening 3b: Chamber small space 4a, 4b, 4c: Gas distribution chamber 5: Chamber upper structure 6a, 6b, 6c: Spacers 7a, 7b: Gas dispersion plate 8: Shower plate 9: Nozzle 10: Halogen lamp 11: Transparent window 15: Gate valve 16: Gate valve drive shaft 18: Exhaust vent 20a, 20b: Exhaust piping 21: Pressure regulating valve 22: Main valve 22a: Main valve drive shaft 23: Turbomolecular pump (TMP) 24: Transport Room 25: Hand (End Effector) 26, 26': Dry pump 27: Discharge piping 28: Pressure gauge (for chamber) 29: Pressure gauge (for exhaust piping) 30: Gas box (MFC unit) 31: Exhaust means G1C: Final supply valve (process gas line leading to the chamber) G1E: Final discharge valve (discard gas line leading to exhaust pipe 20a) 51: Exhaust plate 52: Exhaust port 55: Exhaust section partition plate 56, 56i: Rotary force drive and introduction equipment 56': Rotary drive equipment 56a: Rotary drive unit 57: Exhaust cylinder 58: Upper opening plate 59: Upper opening 60: Lower opening plate 61: Lower hole 62: Swivel plate 62f, 62f1, 62f2, 62f3, 62f4: Flap rotating plates (rotor wings) 63: Opening 64, 64', 64o, 64i, 64f: Stage and exhaust mounting base 65: TMP Bass 66: Swivel and vertical mechanism 67: Fixed mounting base 68: Pressure gauge 69: Pivot point 71: Gas piping 73: Gas supply valve 77: Outer peripheral support ring 78: Protrusion 78': Protrusion 79: Swivel drive shaft 81: Vacuum bellows 82: Post 83: Up / Down Drive Equipment 84: Bass 85: Mobile base 91: Exhaust ring 92: Exhaust port 93: Circular exhaust passage 94: Side exhaust passage 95: Vertical exhaust passage 96: Pressure gauge 97: Discharge flange 98: Pressure regulating valve 99: Discharge pipe 100: Spacer 101: Shield 102: Exhaust Chamber 110: Surface treatment equipment

Claims

1. A pressure control method for a surface treatment apparatus, which has a sample stage on which the workpiece is placed when surface treating a workpiece in a processing chamber isolated from the atmosphere, wherein a process gas is supplied to the workpiece on the sample stage during the process, and the gas in the processing chamber is discharged from around the sample stage, The sample stage on which the workpiece is placed has an exhaust port and an exhaust path corresponding to the exhaust port, and a pressure regulating valve is located in the exhaust path, and the exhaust of gas is controlled by opening and closing the pressure regulating valve. A pressure control method characterized in that the cylindrical space between the sample stage and the side wall of the processing chamber is divided into multiple sections, each of which serves as an exhaust path, an exhaust port is provided on the upstream side of the exhaust path, and a pressure regulating valve is provided on the downstream side of the exhaust path.

2. In the pressure control method described in claim 1, A pressure control method characterized in that the conductance of the exhaust port is smaller than the conductance of the pressure regulating valve when it is fully open.

3. In the pressure control method described in claim 1, A pressure control method comprising installing a pressure gauge in the exhaust path and controlling the opening degree of the pressure regulating valve by referring to the pressure obtained from the pressure gauge.

4. A pressure control method for a surface treatment apparatus, wherein, when surface treating a workpiece in a processing chamber isolated from the atmosphere, the apparatus has a sample stage on which the workpiece is mounted, and during the process, a process gas is supplied to the workpiece on the sample stage, and the gas in the processing chamber is discharged from around the sample stage, The sample stage on which the workpiece is placed has an exhaust port and an exhaust path corresponding to the exhaust port, and a pressure regulating valve is located in the exhaust path, and the exhaust of gas is controlled by opening and closing the pressure regulating valve. A pressure control method characterized in that a substantially cylindrical space between the sample stage and the side wall of the processing chamber is used as a common exhaust path, and a plurality of independently controlled pressure regulating valves are provided in a circumferential manner at the lower part of the structure of the sample stage.

5. In the pressure control method described in claim 1, A pressure control method characterized by providing an exhaust port on the inner wall of the processing chamber on the side of the workpiece during the aforementioned process, providing a plurality of exhaust paths that penetrate the processing chamber vertically from the exhaust port, and arranging the independently controllable pressure regulating valves in each of the exhaust paths.

6. In the pressure control method described in claim 1, A pressure control method characterized by providing a function that allows a gas to be discharged separately and independently into the exhaust path downstream of the workpiece in the processing chamber, separate from the discharge of the process gas, and by controlling whether or not to discharge the gas, or by varying the gas flow rate, thereby changing the exhaust of gas around the workpiece.

7. In the pressure control method described in claim 1, A pressure control method characterized by providing a plurality of process gas outlets above the workpiece substantially opposite to the workpiece, controlling whether or not to flow the process gas, varying the gas flow rate, and controlling the direction of gas flow in conjunction with the control of the pressure regulating valve, thereby evenly flowing the process gas horizontally over time onto the workpiece surface.

8. A surface treatment apparatus for surface-treating a workpiece in a processing chamber isolated from the atmosphere, comprising a sample stage on which the workpiece is mounted, a process gas being supplied to the workpiece on the sample stage during the process, and the gas in the processing chamber being discharged from around the sample stage, The sample stage on which the workpiece is placed has an exhaust port and an exhaust path corresponding to the exhaust port, and a pressure regulating valve is located in the exhaust path, and the exhaust of gas is controlled by opening and closing the pressure regulating valve. A surface treatment apparatus characterized in that the cylindrical space between the sample stage and the side wall of the processing chamber is divided into multiple sections, each of which serves as an exhaust path, an exhaust port is provided on the upstream side of the exhaust path, and a pressure regulating valve is provided on the downstream side of the exhaust path.

9. In the surface treatment apparatus according to claim 8, A surface treatment apparatus characterized in that the conductance of the exhaust port is smaller than the conductance when the pressure regulating valve is fully open.

10. In the surface treatment apparatus according to claim 8, A surface treatment apparatus characterized by providing a pressure gauge in the exhaust path and controlling the opening degree of the pressure regulating valve by referring to the pressure obtained from the pressure gauge.

11. A surface treatment apparatus for surface treatment of a workpiece in a processing chamber isolated from the atmosphere, comprising a sample stage on which the workpiece is mounted, a process gas being supplied to the workpiece on the sample stage during the process, and the gas in the processing chamber being discharged from around the sample stage, The sample stage on which the workpiece is placed has an exhaust port and an exhaust path corresponding to the exhaust port, and a pressure regulating valve is located in the exhaust path, and the exhaust of gas is controlled by opening and closing the pressure regulating valve. A surface treatment apparatus characterized in that a substantially cylindrical space between the sample stage and the side wall of the processing chamber is used as a common exhaust path, and a plurality of independently controlled pressure regulating valves are provided in a circumferential manner at the lower part of the structure of the sample stage.

12. In the surface treatment apparatus according to claim 8, A surface treatment apparatus characterized by providing an exhaust port on the inner wall of the processing chamber on the side of the workpiece during the aforementioned process, providing a plurality of exhaust paths that penetrate the processing chamber vertically from the exhaust port, and arranging the independently controllable pressure regulating valves in each of the exhaust paths.

13. In the surface treatment apparatus according to claim 8, A surface treatment apparatus characterized by providing a function that allows for the separate and independent discharge of gas into the exhaust path downstream of the workpiece within the processing chamber, distinct from the discharge of the process gas, and by controlling whether or not to discharge the gas, or by varying the gas flow rate, thereby altering the exhaust of gas around the workpiece.

14. In the surface treatment apparatus according to claim 8, A surface treatment apparatus characterized by providing a plurality of process gas outlets above the workpiece substantially opposite to the workpiece, controlling whether or not to flow the process gas, varying the gas flow rate, and controlling the direction of gas flow in conjunction with the control of the pressure regulating valve, thereby evenly flowing the process gas horizontally over time onto the workpiece surface.

15. In the surface treatment apparatus according to claim 8, A surface treatment apparatus characterized in that the rotation direction of the rotor blades of the pressure regulating valve is shielded from the opening such that it intersects substantially perpendicularly with respect to the direction of gas flow from upstream to downstream of the exhaust path.

16. In the surface treatment apparatus according to claim 8, A surface treatment apparatus characterized in that the blade surface of the rotor of the pressure regulating valve rotates approximately 90 degrees in the direction of the gas flow from upstream to downstream of the exhaust path, from a position where it coincides with the flow to a position where it is perpendicular and shielding the flow.

17. In the surface treatment apparatus according to claim 15, A surface treatment apparatus characterized in that the rotor blades of the pressure regulating valves partially overlap in the direction of gas flow, do not interfere with each other, and can be set independently.

18. In the surface treatment apparatus according to claim 8, A surface treatment apparatus characterized in that the power equipment for driving the rotation of the pressure regulating valve is housed within the structure of the sample stage.

19. In the surface treatment apparatus according to claim 8, A surface treatment apparatus characterized in that the power equipment for driving the rotation of the pressure regulating valve is arranged to rotate around the outside of the exhaust path at the bottom of the processing chamber, on the atmospheric side.

20. In the surface treatment apparatus according to claim 15 or claim 18, A surface treatment apparatus characterized in that, when the pressure regulating valve is fully opened, the rotor blades of the pressure regulating valve can be retracted to a position that does not obstruct the gas flow within the bottom surface of the lower part of the structure of the sample stage.

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