TWI861262B - Gas supply method and substrate processing device - Google Patents

Abstract

[Topic] Provide a gas supply method and substrate processing device that is beneficial to "divide the gas to a plurality of branch pipes according to the diversion ratio, and stably supply the gas in a short time when the diverted gas is supplied to the processing container." [Solution] A gas supply method comprises: when processing a substrate, closing the second valve and opening the first valve to supply gas to the gas supply piping, branch piping, and gas diversion ratio control element located on the secondary side of a gas flow control device; detecting by a pressure sensor that the pressure of the gas supply piping or the branch piping on the secondary side of the gas flow control device has reached a set pressure; closing the first valve; and opening the first valve and the second valve to supply the gas to a processing container.

Description

Gas supply method and substrate processing device

The present disclosure relates to a gas supply method and a substrate processing apparatus.

Patent document 1 discloses a gas supply method and substrate processing device that "performs pressure ratio control to adjust the split flow rate for the split flow adjustment means so that the pressure ratio in each process gas branch flow path becomes a target pressure ratio, and splits the process gas from the process gas supply means to a plurality of branch pipes." In the gas supply method, when the pressure in each process gas branch flow path is stable, the control of the split flow adjustment means is switched to pressure fixing control, and the additional gas is supplied to the other process gas branch pipe by the additional gas supply means. The pressure fixing control is to adjust the split flow rate by maintaining the pressure in one process gas branch flow path when the pressure is stable. [Prior art literature] [Patent literature]

[Patent Document 1] Japanese Patent Application Publication No. 2007-207808

[Problems to be solved by the present invention]

The present disclosure provides a gas supply method and substrate processing device that are advantageous for "dividing the gas into a plurality of branch pipes according to the diversion ratio, and stably supplying the gas in a short time when the diverted gas is supplied to the processing container." [Means for solving the problem]

One aspect of the present disclosure is a gas supply method, which is to "supply gas to a processing container for processing a substrate, and has: at least one gas flow control device, which is arranged in a gas supply piping from a gas supply section to the aforementioned processing container; a gas split ratio control element, which is respectively arranged in two or more branch pipings branched on the secondary side of the aforementioned gas flow control device, and has a conductance variable flow path that allows the conductance to be freely variable; a gas split ratio control section, which is composed of two or more of the aforementioned gas split ratio control elements; a first valve and a pressure sensor, which are located on the secondary side of the aforementioned gas flow control device and the primary side of the aforementioned gas split ratio control element; and a second valve, which is located The gas supply device of the "secondary side of the gas flow ratio control element" has the following processes: When processing the substrate, the second valve is closed and the first valve is opened to supply the gas to the gas supply piping, the branch piping and the gas flow ratio control element located on the secondary side of the gas flow control device; The pressure sensor is used to detect that the pressure of the gas supply piping or the branch piping on the secondary side of the gas flow control device has reached the set pressure; The first valve is closed; and The first valve and the second valve are opened to supply the gas to the processing container. [Effect of the invention]

According to the present disclosure, a gas supply method and a substrate processing device can be provided that are advantageous for "dividing the gas into a plurality of branch pipes according to the diversion ratio, and stably supplying the gas in a short time when the diverted gas is supplied to the processing container."

The following is a description of the gas supply method and substrate processing apparatus according to the embodiment of the present disclosure with reference to the attached drawings. In addition, in the present specification and drawings, the same symbols are sometimes given to the elements having substantially the same structure, and repeated description is omitted.

[Substrate processing apparatus and gas supply method of the first embodiment] First, referring to FIG. 1 and FIG. 2, an example of a substrate processing apparatus and a gas supply method of the first embodiment of the present disclosure is described. FIG. 1 is a longitudinal cross-sectional view of an example of a substrate processing apparatus of the first embodiment. FIG. 2 is a diagram for explaining the control of the gas supply apparatus and a diagram showing a time history graph of the MFC flow rate and the FRC flow rate.

The substrate processing device 100 shown in FIG. 1 is an inductively coupled plasma (ICP) processing device that performs various substrate processing methods on a substrate G (hereinafter, simply referred to as a "substrate") that is rectangular in top view for a flat panel display (Flat Panel Display, hereinafter referred to as "FPD"). As a material for the substrate G, glass is mainly used, and transparent synthetic resins are sometimes used depending on different uses. Here, the substrate processing includes film forming processing using an etching process or a CVD (Chemical Vapor Deposition) method. Examples of FPD include a liquid crystal display (LCD), an electroluminescence (EL), a plasma display panel (PDP), etc. The substrate G includes a supporting substrate in addition to the form of a circuit patterned on its surface. Furthermore, the planar dimensions of FPD substrates are becoming larger with the change of generations, and the planar dimensions of the substrates G processed by the substrate processing apparatus 100 include, for example, at least the dimensions of about 1500 mm×1800 mm for the 6th generation to about 3000 mm×3400 mm for the 10.5th generation. Furthermore, the thickness of the substrate G is about 0.2 mm to several mm.

The substrate processing apparatus 100 shown in FIG1 comprises: a processing container 20 in a rectangular box shape; a substrate mounting table 70 in a rectangular shape in a top view, which is disposed in the processing container 20 and mounts the substrate G; and a control unit 90. In addition, the processing container may also be in a cylindrical box shape or an elliptical cylindrical box shape, and in this form, the substrate mounting table is also in a circular or elliptical shape, and the substrate mounted on the substrate mounting table is also in a circular shape.

The processing container 20 is divided into two spaces, upper and lower, by the metal window 50. The upper space, namely the antenna room A, is formed by the upper chamber 13, and the lower space, namely the processing area S (processing chamber), is formed by the lower chamber 17. In the processing container 20, a rectangular ring-shaped support frame 14 is provided at a position that becomes a boundary between the upper chamber 13 and the lower chamber 17 in a manner protruding toward the inner side of the processing container 20, and the metal window 50 is mounted on the support frame 14.

The upper chamber 13 forming the antenna room A is formed by the side walls 11 and the top plate 12, and the entire chamber is formed of metal such as aluminum or aluminum alloy.

The lower chamber 17 having a processing area S therein is formed by side walls 15 and a bottom plate 16, and the entire chamber is formed of metal such as aluminum or aluminum alloy. The side walls 15 are grounded by a grounding wire 21.

Furthermore, the support frame 14 is formed of conductive metal such as aluminum or aluminum alloy, and can also be called a metal frame.

A rectangular ring-shaped (endless) sealing groove 22 is formed at the upper end of the side wall 15 of the lower chamber 17. A sealing member 23 such as an O-ring is embedded in the sealing groove 22 and the sealing member 23 is retained by the abutting surface of the support frame 14, thereby forming a sealing structure between the lower chamber 17 and the support frame 14.

A loading and unloading port 18 is provided on the side wall 15 of the lower chamber 17 for loading and unloading the substrate G into and out of the lower chamber 17. The loading and unloading port 18 is configured to be openable and closed by a gate valve 24. A transfer chamber (not shown) containing a transfer mechanism is adjacent to the lower chamber 17, and the gate valve 24 is controlled to be opened and closed, and the substrate G is loaded and unloaded through the loading and unloading port 18 by the transfer mechanism.

Furthermore, a plurality of exhaust ports 19 are provided on the bottom plate 16 of the lower chamber 17, and a gas exhaust pipe 25 is connected to each exhaust port 19, and the gas exhaust pipe 25 is connected to an exhaust device 27 via a switch valve 26. A gas exhaust section 28 is formed by the gas exhaust pipe 25, the switch valve 26, and the exhaust device 27. The exhaust device 27 is configured as a vacuum pump having a turbomolecular pump, etc., and can freely evacuate the lower chamber 17 to a predetermined vacuum degree during the process. In addition, a pressure gauge (not shown) is provided at an appropriate position of the lower chamber 17, and monitoring information of the pressure gauge is sent to the control unit 90.

The substrate mounting table 70 includes a base material 73 and an electrostatic chuck 76 formed on an upper surface 73 a of the base material 73 .

The substrate 73 is formed by a stack of an upper substrate 71 and a lower substrate 72. The upper substrate 71 is rectangular in plan view and has the same plane size as the FPD mounted on the substrate mounting table 70. For example, the upper substrate 71 has the same plane size as the mounted substrate G, and the length of the long side can be set to about 1800 mm to 3400 mm, and the length of the short side can be set to about 1500 mm to 3000 mm. With respect to the plane size, the total thickness of the upper substrate 71 and the lower substrate 72 can be, for example, about 50 mm to 100 mm.

The lower substrate 72 is provided with a temperature control medium flow path 72a which is formed of stainless steel, aluminum, aluminum alloy, etc. and is serpentine to cover the entire area of the rectangular plane. On the other hand, the upper substrate 71 is also formed of stainless steel, aluminum, aluminum alloy, etc. In addition, the temperature control medium flow path 72a may be provided on the upper substrate 71 or the electrostatic chuck 76, for example. Furthermore, the substrate 73 may also be formed of a single component such as aluminum or aluminum alloy, instead of being formed of a stack of two components as shown in the example.

A box-shaped pedestal 78 formed of an insulating material and having a section inside is fixed to the bottom plate 16 of the lower chamber 17 , and the substrate mounting table 70 is mounted on the section of the pedestal 78 .

On the upper substrate 71, an electrostatic chuck 76 is formed to directly place the substrate G. The electrostatic chuck 76 comprises: a dielectric film, i.e., a ceramic layer 74, formed by spraying ceramics such as alumina; and a conductive layer 75 (electrode) buried inside the ceramic layer 74 and having an electrostatic adsorption function.

The conductive layer 75 is connected to a DC power source 85 via a power supply line 84. When a switch (not shown) disposed between the power supply lines 84 is turned on by the control unit 90, a DC voltage is applied from the DC power source 85 to the conductive layer 75, thereby generating a Coulomb force. The substrate G is electrostatically attracted to the top of the electrostatic chuck 76 by the Coulomb force, and is held in a state of being placed on the top of the upper substrate 71.

A temperature control medium flow path 72a is provided on the lower substrate 72 constituting the substrate mounting table 70, which is serpentine to cover the entire area of the rectangular plane. At both ends of the temperature control medium flow path 72a, there are connected: a delivery pipe 72b for supplying the temperature control medium to the temperature control medium flow path 72a; and a return pipe 72c for discharging the temperature control medium that has been heated by flowing through the temperature control medium flow path 72a.

As shown in FIG1 , the delivery pipe 72b and the return pipe 72c are connected to a delivery flow path 87 and a return flow path 88, respectively, and the delivery flow path 87 and the return flow path 88 are connected to a cooler 86. The cooler 86 has: a main body for controlling the temperature or discharge flow rate of the temperature control medium; and a pump for pressurizing the temperature control medium (both not shown). In addition, a refrigerant is used as the temperature control medium, and Galden (registered trademark) or Fluorinert (registered trademark) or the like is used as the refrigerant. The delivery flow path 87, the return flow path 88 and the cooler 86 constitute a temperature control device 89. Although the temperature control form of the example shown in the figure is a form in which the temperature control medium is circulated in the lower substrate 72, it is also possible to have a built-in heater in the lower substrate 72 and to control the temperature by the heater, or it is also possible to have a form in which the temperature control is performed by both the temperature control medium and the heater. In addition, the heater can be replaced by circulating a high-temperature temperature control medium to perform temperature control accompanied by heating. In addition, the heater as a resistor is formed of a compound of tungsten or molybdenum or any of these metals and aluminum oxide or titanium. In addition, although the example shown in the figure has a temperature control medium flow path 72a formed in the lower substrate 72, for example, the upper substrate 71 or the electrostatic chuck 76 may also have a temperature control medium flow path.

The upper substrate 71 is provided with a temperature sensor such as a thermocouple, and monitoring information of the temperature sensor is sent to the control unit 90 at any time. Then, based on the sent monitoring information, the control unit 90 performs temperature control of the upper substrate 71 and the substrate G. More specifically, the control unit 90 adjusts the temperature or flow rate of the temperature control medium supplied from the cooler 86 to the conveying flow path 87. Then, the temperature control of the substrate mounting table 70 is performed by circulating the temperature-controlled or flow-controlled temperature control medium in the temperature control medium flow path 72a. In addition, a temperature sensor such as a thermocouple may be provided on the lower substrate 72 or the electrostatic chuck 76, for example.

A step is formed by the outer periphery of the electrostatic chuck 76 and the upper substrate 71 and the upper surface of the rectangular member 78. A rectangular frame-shaped focusing ring 79 is placed on the step. When the focusing ring 79 is placed on the step, the upper surface of the focusing ring 79 is set lower than the upper surface of the electrostatic chuck 76. The focusing ring 79 is made of ceramics such as alumina or quartz.

A power supply component 80 is connected to the bottom of the lower substrate 72. A power supply line 81 is connected to the lower end of the power supply component 80. The power supply line 81 is connected to a bias power source, i.e., a high-frequency power source 83, via a matching device 82 for impedance matching. A high-frequency power of, for example, 3.2 MHz is applied to the substrate mounting table 70 from the high-frequency power source 83, thereby generating an RF bias and attracting ions generated by the high-frequency power source 59, which is a source for plasma generation described below, to the substrate G. Therefore, in the plasma etching process, the etching rate and the etching selectivity can be improved at the same time. In addition, a through hole (not shown) can be opened in the lower substrate 72, and the power supply component 80 passes through the through hole and is connected to the bottom of the upper substrate 71. In this way, the substrate mounting table 70 mounts the substrate G and forms a bias electrode for generating RF bias. At this time, the portion that becomes the ground potential inside the chamber functions as a counter electrode of the bias electrode and forms a return circuit for high-frequency power. In addition, the metal window 50 can also be formed as a part of the return circuit for high-frequency power.

The metal window 50 is formed of a plurality of divided metal windows 57. The number of divided metal windows 57 forming the metal window 50 (in FIG. 1 , four are shown in the cross-sectional direction) can be set to various numbers such as 12 or 24.

Each divided metal window 57 is insulated from the support frame 14 or the adjacent divided metal window 57 by the insulating member 56. Here, the insulating member 56 is formed of a fluororesin such as PTFE (Polytetrafluoroethylene).

The divided metal window 57 has: a conductive plate 30; and a spray plate 40. The conductive plate 30 and the spray plate 40 are both formed of "a non-magnetic, conductive and corrosion-resistant metal or a metal subjected to a corrosion-resistant surface treatment, i.e., aluminum or aluminum alloy, stainless steel, etc." The corrosion-resistant surface treatment is, for example, anodic oxidation treatment or ceramic spraying. In addition, a plasma-resistant coating by anodic oxidation treatment or ceramic spraying may also be applied to the bottom of the spray plate 40 facing the treatment area S. The conductive plate 30 is grounded via a grounding wire (not shown), and the spray plate 40 is also grounded via the conductive plates 30 joined to each other.

As shown in FIG1 , a spacer (not shown) formed of an insulating member is disposed above each divided metal window 57, and a high-frequency antenna 54 is disposed by the spacer to be spaced apart from the conductor plate 30. The high-frequency antenna 54 is formed by "winding an antenna line formed of a metal with good electrical conductivity such as copper into a ring or spiral shape." For example, multiple ring-shaped antenna lines may be disposed.

Furthermore, the high frequency antenna 54 is connected to a power supply member 57a extending above the upper chamber 13, and a power supply line 57b is connected to the upper end of the power supply member 57a. The power supply line 57b is connected to a high frequency power source 59 via a matching device 58 for impedance matching. A high frequency power of, for example, 13.56 MHz is applied to the high frequency antenna 54 from the high frequency power source 59, thereby forming an induced electric field in the lower chamber 17. By the induced electric field, the processing gas supplied from the shower plate 40 to the processing area S is plasmatized to generate inductively coupled plasma, and ions in the plasma are supplied to the substrate G. Furthermore, each divided metal window 57 has a unique high-frequency antenna, and can also perform control of applying high-frequency power to each high-frequency antenna individually.

The high-frequency power source 59 is a source for generating plasma, and the high-frequency power source 83 connected to the substrate mounting table 70 becomes a bias source for attracting the generated ions and giving kinetic energy. In this way, in the ion source, plasma is generated by inductive coupling, and the other power source, i.e., the bias source, is connected to the substrate mounting table 70 to control the ion energy. In this way, the generation of plasma and the control of ion energy can be performed independently, thereby increasing the degree of freedom of the process. The frequency of the high-frequency power output from the high-frequency power source 59 is preferably set in the range of 0.1~500MHz.

The metal window 50 is formed of a plurality of divided metal windows 57, and each divided metal window 57 is suspended from the ceiling 12 of the upper chamber 13 by a plurality of suspension rods (not shown). Since the high-frequency antenna 54 that helps generate plasma is arranged on the divided metal windows 57, the high-frequency antenna 54 is suspended from the ceiling 12 via the divided metal windows 57.

A gas diffusion groove 32 is formed on the bottom of the conductor plate body 31 forming the conductor plate 30. In addition, the gas diffusion groove may also be opened on the top of the spray plate. Moreover, the shape of the gas diffusion groove includes not only a concave shape formed in a long strip shape but also a concave shape formed in a plane shape.

A plurality of gas discharge holes 42 are formed in the spray plate body 41 forming the spray plate 40. The gas discharge holes 42 penetrate the spray plate body 41 and are connected to the gas diffusion groove 32 and the processing area S of the conductive plate 30.

A plurality of (four in the example shown) supply ports 12a are provided on the top plate 12 of the upper chamber 13. For each supply port 12a, a gas introduction pipe 55 is airtightly connected to each divided metal window 57. A branch pipe 69 constituting a gas supply device 60 described in detail below is fluidly connected to each gas introduction pipe 55. In the example shown, for example, four branch pipes 69 are fluidly connected to the gas introduction pipe 55, and the processing gas is supplied from the four gas introduction pipes 55 to the four divided metal windows 57, respectively. In this regard, when there are three or fewer divided metal windows 57 or five or more divided metal windows 57, it is also possible to adopt a configuration in which "any two of the four gas introduction tubes 55 are intertwined into one and the fluid is connected to one divided metal window 57". Furthermore, it is also possible to adopt a configuration in which "the four gas introduction tubes 55 are respectively branched into a plurality of divided metal windows 57 in the antenna room A and the fluid is connected to five or more divided metal windows 57".

The gas supply device 60 includes a gas supply portion 61, a gas supply pipe 68 connected to the gas supply portion 61, and a branch pipe 69 that branches from the gas supply pipe 68 into four and connects to the corresponding gas introduction pipes 55. Various valves or sensors are provided in the gas supply pipe 68 or the branch pipe 69 as described below.

During the plasma treatment, the processing gas supplied from the gas supply device 60 is supplied to the gas diffusion grooves 32 of the conductive plate 30 of each divided metal window 57 through the gas introduction pipe 55. Then, the gas is discharged from each gas diffusion groove 32 to the processing area S through the gas discharge holes 42 of each spray plate 40.

On the downstream side of the gas flow of the gas supply section 61, a gas flow control device 62 such as a mass flow controller (MFC) is provided. In addition, on the secondary side of the gas flow control device 62 (which is the downstream side of the gas flow, and the downstream side is referred to as the secondary side relative to the object. The same applies to the following.), a first valve 63 is provided to block the gas flow toward the gas supply piping 68 located on the downstream side. Moreover, on the secondary side of the first valve 63 and the primary side of the branch piping 69 (which is the upstream side of the gas flow, and the upstream side is referred to as the primary side relative to the object. The same applies to the following.), a third valve 65 is provided. In addition, it is also possible to be a form without the third valve 65.

In the gas supply pipe 68, between the first valve 63 and the third valve 65, a pressure sensor 64 such as a pressure switch is provided.

The four branch pipes 69 are respectively provided with gas diversion ratio control elements 66A, 66B, 66C, and 66D such as FRC (Flow Ratio Controller). The gas diversion ratio control elements 66A, 66B, 66C, and 66D all have variable conductance flow paths (not shown) that allow the conductance to be freely variable. More specifically, they are internally provided with laminar flow elements (diversion) or hot wire sensors, flow control valves, and flow limiting orifices (all not shown). Moreover, each gas diversion ratio control element 66A, 66B, 66C, and 66D adjusts the opening and closing degree of the inherent flow limiting orifice, thereby adjusting the diversion amount (diversion ratio) of the process gas diverted to each branch pipe. In addition, in each gas flow ratio control element 66A, 66B, 66C, and 66D, the processing gas flows to the secondary side due to the pressure difference (differential pressure) in the piping between the primary side and the secondary side.

In the example shown in the figure, the gas split ratio control unit 66 is formed by four gas split ratio control elements 66A, 66B, 66C, and 66D. In the gas split ratio control unit 66, the conductances of the plurality of gas split ratio control elements 66A, 66B, 66C, and 66D are variably controlled, thereby controlling the gas flow ratios supplied to the plurality of branch pipes 69.

In each branch pipe 69, on the secondary side of the gas flow ratio control elements 66A, 66B, 66C, 66D, a unique second valve 67A, 67B, 67C, 67D is respectively provided.

Through each branch pipe 69 interposed with four gas diversion ratio control elements 66A, 66B, 66C, and 66D, the inherent divided metal window 57 is supplied with the processing gas diverted at a preset diversion ratio. Specifically, for example, it is the central processing area, the central part of the end edge in the peripheral processing area, the corner part in the peripheral processing area, the middle processing area between the central processing area and the peripheral processing area, etc. Each of the four gas introduction pipes 55 corresponds to the above-mentioned four areas. In addition, the number of areas is not limited to four, and can be five or six or more as needed. In this case, the number of corresponding gas introduction pipes 55 also becomes the corresponding number. That is, when there are five zones, the number of gas introduction pipes 55 becomes five, and when there are six zones, the number of gas introduction pipes 55 becomes six, and so on. This is also the case with respect to the gas split ratio control unit 66 or the branch pipe 69 located on the upstream side of the gas introduction pipe 55. In addition, the divided metal windows 57 constituting each zone may also be plural. In this case, the gas is branched from the gas introduction pipe 55 corresponding to each zone and connected to each of the plural divided metal windows 57. In this case, the split ratio of the process gas supplied to each processing zone is preset in accordance with the recipe (process recipe). In addition, in the example shown in the figure, in order to simplify the explanation, the four divided metal windows 57 in the device cross section correspond to the four areas of the processing area S.

In addition, the example shown in the figure shows a configuration in which a gas supply pipe 68 is extended from a single gas supply section 61, and four branch pipes 69 are extended by branching in the middle of the gas supply pipe 68, but other configurations are also possible. For example, a configuration in which "individual gas supply pipes are extended from a plurality of gas supply sections, and each gas supply pipe is branched into a plurality of gas supply pipes to have a plurality of branch pipes" can be cited. Various process gases used for various processes such as film forming process and etching process are supplied to the gas supply pipe 68 from the single gas supply section 61 as process gases. Furthermore, in the configuration having a plurality of gas supply units, in addition to supplying a plurality of process gases for film forming or etching from each gas supply unit, there is also a configuration in which a process gas for film forming is supplied from one gas supply unit and a carrier gas such as a rare gas is supplied from another gas supply unit. In addition to these, there is also a configuration in which oxygen gas for controlling the deposition of reaction products is supplied from another gas supply unit, and in this specification, these rare gases or oxygen gas are also included in the process gas.

The control device 90 controls the operation of each component of the substrate processing device 100, such as the cooler 86 or the high-frequency power supply 59, 83, the gas supply device 60, and the gas exhaust part 28 based on the monitoring information sent from the pressure gauge. The control unit 90 has a CPU (Central Processing Unit), a ROM (Read Only Memory) and a RAM (Random Access Memory). The CPU executes a predetermined process according to a recipe stored in a memory area of the RAM or ROM. The recipe is set with control information of the substrate processing device 100 relative to the process conditions. The control information includes, for example, the gas flow rate or the pressure in the processing container 20, the temperature in the processing container 20 or the temperature of the substrate 72 below, the process time, etc.

The program used by the recipe and control device 90 may be stored in a hard disk, optical disk, optical magnetic disk, etc., for example. In addition, the recipe, etc. may be stored in a storage medium such as a CD-ROM, DVD, memory card, etc. that can be read by a portable computer, and then set in the control unit 90 and read out. The control unit 90 also has a user interface such as an input device such as a keyboard or mouse for inputting commands, a display device such as a display that visually displays the operating status of the substrate processing device 100, and an output device such as a printer.

Next, the gas supply method of the first embodiment will be described.

As described above, according to the recipe, the diversion ratio of the processing gas to each branch pipe 69 "connected to each divided metal window 57 corresponding to multiple areas (central area, peripheral area, etc.) of the processing area S" is set, and the diversion ratio of each recipe is stored in the control device 90.

When the substrate G is processed by supplying the processing gas from the gas supply unit 61 based on a certain recipe, the control device 90 first performs the following control: the second valves 67A, 67B, 67C, and 67D of each branch pipe 69 are closed, and the first valve 63 and the third valve 65 are opened.

By this control, the processing gas is supplied to the gas supply pipe 68 and each branch pipe 69 and the gas split ratio control elements 66A, 66B, 66C, 66D located on the secondary side of the gas flow control device 62 (a process of supplying gas to the gas supply pipe, the branch pipe, and the gas split ratio control element). That is, by this process, before the processing gas is supplied from the gas supply part 61 to each processing area via the gas flow control device 62, the processing gas is supplied to the inside of the gas split ratio control elements 66A, 66B, 66C, 66D in advance.

Here, referring to Figure 2, the effect of the project is explained. In Figure 2, when the control device 90 starts to control the supply of the process gas to the gas flow control device 62 at time 0 seconds, the supply of the process gas (the gas discharge of the MFC) starts at time t1, and becomes the standard MFC flow rate: Q1 at time t2.

However, in a gas supply device where a branch pipe is present in the middle of the gas supply pipe and an FRC is interposed between each branch pipe, even if the MFC flow rate becomes the standard flow rate, there is a problem that if a certain flow rate of the process gas does not flow to the FRC, the FRC cannot be properly controlled and the process gas of the standard flow rate cannot flow to each FRC. This is because it takes time from the discharge of the gas from the MFC until the process gas of the standard flow rate flows to each FRC.

Since the start of FRC control requires a certain degree of gas flow to the FRC, for example, as shown in FIG. 2, although the process gas starts to flow through the FRC at time t1, the FRC flow (the total flow of all FRC flows) increases in a manner that gradually approaches the standard process flow, i.e., Q1 (see the dotted line curve). As a result, it takes time until the FRC flow becomes the process flow, i.e., Q1 (or close to Q1), and it also takes time until the flow of each FRC can be controlled. Therefore, the start time of FRC control becomes time t3, and it takes a long time Δt1 from time 0 seconds (see the two-point chain curve). As a result, it takes time until the flow ratio of the process gas supplied to the process area S becomes stable.

Therefore, in the gas supply method of the present embodiment, in the process of supplying gas to the above-mentioned gas supply piping, branch piping, and gas diversion ratio control element, at the stage of 0 seconds from the moment when the gas supply starts from the MFC, a certain degree of flow rate Q2 (<Q1) of the treated gas is circulated to the FRC already located in each branch piping. Through this process, the time until the FRC flow rate (the total flow rate of all FRC flows) approaches the treated flow rate, i.e., Q1, becomes extremely short (see the one-point chain curve). Thereby, the time until the flow rate of each FRC can be controlled is shortened. Therefore, as shown in FIG2, the start time of FRC control becomes extremely fast from time t3 to time t4 (see the three-point dashed curve). As a result, the flow rate ratio of the process gas supplied to the process area S is stabilized more quickly.

In the above process, the pressure in the gas supply piping 68 on the secondary side of the gas flow control device 62 or the pressure in the branch piping 69 (the primary side of the gas flow ratio control elements 66A, 66B, 66C, 66D) is always measured by the pressure sensor 64 located between the first valve 63 and the third valve 65. The measured data is sent to the control device 90 at any time.

The control device 90 stores data on a set pressure. The set pressure is a pressure suitable for starting the FRC control as early as possible, for example, the set pressure can be set within a range of 50 Torr to 300 Torr (1 Torr = 133.4 Pa).

Furthermore, when the control device 90 detects that the pressure caused by the pressure sensor 64 has reached the set pressure (process of detecting that the set pressure has been reached), the control device 90 then performs control to close the first valve 63 (process of closing the first valve).

In this way, the first valve 63 and the second valves 67A, 67B, 67C, and 67D in each branch pipe 69 are closed, whereby the pressure in the gas supply pipe 68 on the secondary side of the gas flow control device 62 and the pressure in the branch pipe 69 (the primary side of the gas diversion ratio control elements 66A, 66B, 66C, and 66D) are maintained at the set pressure.

Thereafter, the control device 90 controls the opening of the first valve 63 and the second valves 67A, 67B, 67C, and 67D at a time point preset in accordance with the recipe, and the processing gas is supplied to the corresponding area in the processing area S through each branch pipe 69 (a process of supplying gas to the processing container).

According to the substrate processing apparatus 100 and the gas supply method of the present embodiment, the time until the FRC reaches the standard flow rate can be shortened by "pre-supplying a certain degree of flow rate of gas to the inside of the FRC when processing the substrate G". Moreover, in this case, the processing gas can be stably supplied to the processing area S in a short time. In addition, when it is desired to obtain the same effect by optimizing the volume (length or thickness, etc.) of the gas supply piping or the branch piping, since the processing gas to be flowed is different for each application of the apparatus, although it is necessary to change various pipings for each apparatus to make it the optimal volume, it is not necessary to change such hardware.

[Substrate processing apparatus and gas supply method of the second embodiment] Next, referring to FIG. 3, an example of a substrate processing apparatus and a gas supply method of the second embodiment of the present disclosure is described. Here, FIG. 3 is a longitudinal cross-sectional view of an example of a substrate processing apparatus of the second embodiment.

The substrate processing apparatus 100A is different from the substrate processing apparatus 100 in that it has a gas supply apparatus 60A. The gas supply apparatus 60A has: a main gas supply system for supplying a main gas; and an auxiliary gas supply system for supplying an auxiliary gas.

Here, the main gas and the auxiliary gas are the same type or different types of processing gases, and both or either one of them is various processing gases used for various processes such as film forming processing and etching processing, carrier gases such as rare gases, oxygen gas for controlling the deposition of reaction products, etc. In this specification, both are included in the processing gas, and the gas mixed with the main gas and the auxiliary gas is also included in the processing gas.

The main gas supply system includes a main gas supply portion 61A (gas supply portion) and a main gas supply pipe 68A (an example of a gas supply pipe) connected to the main gas supply portion 61A. The main gas supply system further includes a main gas branch pipe 69A (an example of a branch pipe) branching from the main gas supply pipe 68A into four branches and connected to the corresponding gas introduction pipes 55.

A gas flow control device 62A (gas flow control device) for main gas is provided on the secondary side of the main gas supply portion 61A, and a first valve 63A is provided on the secondary side of the gas flow control device 62A for main gas. A third valve 65A is provided on the secondary side of the first valve 63A and on the primary side of the main gas branch pipe 69A. A pressure sensor 64A is provided between the first valve 63A and the third valve 65A.

The four main gas branch pipes 69A are provided with gas flow ratio control elements 66A, 66B, 66C, and 66D, respectively. In addition, in each branch pipe 69A, a second valve 67A, 67B, 67C, and 67D is provided on the secondary side of the gas flow ratio control elements 66A, 66B, 66C, and 66D, respectively.

On the other hand, the auxiliary gas supply system includes an auxiliary gas supply portion 61B (gas supply portion) and an auxiliary gas supply pipe 68B (an example of a gas supply pipe) connected to the auxiliary gas supply portion 61B. The auxiliary gas supply system further includes an auxiliary gas branch pipe 69B (an example of a branch pipe) branching from the auxiliary gas supply pipe 68B into four branches and connected to the corresponding gas introduction pipes 55.

A gas flow control device 62B (gas flow control device) for auxiliary gas is provided on the secondary side of the auxiliary gas supply portion 61B, and a first valve 63B is provided on the secondary side of the gas flow control device 62B for auxiliary gas. A third valve 65B is provided on the secondary side of the first valve 63B and on the primary side of the auxiliary gas branch pipe 69B. A pressure sensor 64B is provided between the first valve 63B and the third valve 65B.

The four auxiliary gas branch pipes 69B are provided with gas flow ratio control elements 66E, 66F, 66G, and 66H, respectively. In addition, in each branch pipe 69B, a second valve 67E, 67F, 67G, and 67H is provided on the secondary side of the gas flow ratio control elements 66E, 66F, 66G, and 66H, respectively.

Moreover, the gas split ratio control unit 66 is constituted by eight gas split ratio control elements 66A, 66B, 66C, 66D, 66E, 66F, 66G, and 66H.

The secondary sides of the second valves 67A, 67B, 67C, and 67D in each main gas branch pipe 69A constituting the main gas supply system are connected to the secondary sides of the second valves 67E, 67F, 67G, and 67H in each auxiliary gas branch pipe 69B constituting the auxiliary gas supply system.

In the gas supply method of the second embodiment, the set pressure in the main gas supply system and the set pressure in the auxiliary gas supply system can be the same pressure or different pressures, and the control content of the control device 90 for the two gas supply systems is the same as that of the gas supply method of the first embodiment.

That is, the main gas supply system and the auxiliary gas supply system both allow a certain degree of flow of the process gas to flow to the gas split ratio control elements 66A~66H in advance, and when the pressure gauges 64A and 64B respectively reach the set pressure, the first valves 63A and 63B are closed. In addition, in accordance with the recipe, the first valves 63A and 63B and the second valves 67A~67H are opened, thereby, in the secondary side of the second valves 67A~67D, the main gas and the auxiliary gas corresponding to the split ratio are mixed to generate four types of process gases. The generated process gases are supplied to the corresponding four areas in the process area S through the branch pipes 69A. In addition, the number of areas corresponding to the processing area S is not limited to four, which is the same as the first embodiment, and the number of areas can also be five, six or more. In this case, the supply system of the main gas and the auxiliary gas is also set according to the number of areas.

[Experiment to verify the time until stable supply of processing gas] The inventors of the present invention conducted the following experiment: a substrate processing device as shown in FIG3 was manufactured, and the set pressures of the main gas supply system and the auxiliary gas supply system were varied, and the time until stable supply of processing gas (final convergence time) was measured. Here, the final convergence time refers to the time until the differential ratio with the target gas flow rate becomes less than ±2%.

In this experiment, the area where the processing gas is pre-stored is different. Specifically, in FIG. 3, the control of "closing the third valve 65A, 65B and storing the processing gas on the primary side of the third valve 65A, 65B" (in the FRC, the processing gas is not pre-supplied) is used as comparative examples 1 to 5, and the control of pre-supplying the processing gas to the FRC is used as embodiments 1 to 4. In addition, the conventional control method of "not pre-supplying the processing gas to the FRC and the pressure in each supply system is 0" is used as a reference example. In the following Table 1, various conditions and experimental results of the reference example, each comparative example, and each embodiment are shown.

As can be seen from Table 1, compared with the reference example, the final convergence time of Comparative Examples 3 and 4 becomes longer and the effect cannot be obtained.

It can be seen that the final convergence time of each embodiment is shortened compared with the reference example. In the embodiment 4 where the set pressures of the main gas supply system and the auxiliary gas supply system are both 200 Torr, the final convergence time is particularly shortened to less than 20%, which proves that it is better to set the pressures in the supply piping systems of the two to the same level of about 200 Torr.

Other embodiments may be formed by combining other components with the above-mentioned embodiments, and the present disclosure is not limited to any of the components shown here. In this regard, changes may be made within the scope of the present disclosure and may be appropriately determined according to the application.

For example, although the substrate processing apparatus 100, 100A shown in the illustrated example is described as an inductively coupled plasma processing apparatus having a metal window, as long as the gas is supplied to a plurality of regions in a processing container at a predetermined flow ratio, it may be an inductively coupled plasma processing apparatus having a dielectric window instead of a metal window, or may be a plasma processing apparatus of another form. Specifically, they include Electron Cyclotron Resonance Plasma (ECP) or Helicon Wave Plasma (HWP), Capacitively Coupled Plasma (CCP). In addition, Microwave Activated Surface Wave Plasma (SWP) can be cited. These plasma processing devices include ICP and can independently control the ion flux and ion energy, and can freely control the etching shape or selectivity, while obtaining an electron density as high as 10 ¹¹ ~10 ¹³ cm ^-3 .

20: Processing container 60,60A: Gas supply device 61,61A,61B: Gas supply unit 62,62A,62B: Gas flow control device 63,63A,63B: First valve 66: Gas flow ratio control unit 66A~66H: Gas flow ratio control element 67,67A~67H: Second valve 68,68A,68B: Gas supply piping 69,69A,69B: Branch piping G: Substrate

[FIG. 1] is a longitudinal sectional view showing an example of a substrate processing apparatus of the first embodiment. [FIG. 2] is a diagram for explaining the control of a gas supply device and a diagram showing a time history graph of an MFC flow rate and an FRC flow rate. [FIG. 3] is a longitudinal sectional view showing an example of a substrate processing apparatus of the second embodiment.

11: Side wall

12: Top plate

12a: Supply port

13: Upper chamber

14: Support frame

15: Side wall

16: Bottom plate

17: Lower chamber

18: Moving in and out

19: Exhaust port

20: Processing container

21: Ground wire

22: Sealing groove

23: Sealing components

24: Gate valve

25: Gas exhaust pipe

26: Switch valve

27: Exhaust device

28: Gas exhaust section

30: Conductor plate

31: Conductor board body

32: Gas diffusion channel

40:Spray board

41: Spray board body

42: Gas outlet hole

50:Metal window

54: High frequency antenna

55: Gas inlet tube

56: Insulation components

57: Split metal window

57a: Power supply components

57b: Power supply line

58:Matcher

59: High frequency power supply

60: Gas supply device

61: Gas supply unit

62: Gas flow control device

63: First valve

64: Pressure sensor

65: The third valve

66: Gas split ratio control unit

66A: Gas split ratio control element

66B: Gas split ratio control element

66C: Gas split ratio control element

66D: Gas split ratio control element

67A: Second valve

67B: Second valve

67C: Second valve

67D: Second valve

68: Gas supply piping

69: Branch piping

70: Substrate mounting table

71: Upper substrate

72: Lower substrate

72a: Temperature regulating medium flow path

72b:Transport piping

72c: Return piping

73: Base material

73a: Above

74: Ceramic layer

75: Conductive layer

76: Electrostatic chuck

78: Pedestal

79: Focus ring

80: Power supply components

81: Power supply line

82:Matcher

83: High frequency power supply

84: Power supply line

85: DC power supply

86: Cooler

87:Transportation path

88: Return flow path

89: Temperature control device

90: Control Department

100: Substrate processing device

A: Antenna room

G: Substrate

S: Processing area

Claims (10)

A gas supply method is provided, in which "a gas is supplied to a processing container for processing a substrate, and comprises: at least one gas flow control device, which is arranged in a gas supply piping from a gas supply section to the aforementioned processing container; a gas split ratio control element, which is respectively arranged in two or more branch pipings branched on the secondary side of the aforementioned gas flow control device, and has a conductance variable flow path that allows the conductance to be freely variable; a gas split ratio control section, which is composed of two or more of the aforementioned gas split ratio control elements; a first valve and a pressure sensor, which are located on the secondary side of the aforementioned gas flow control device and the primary side of the aforementioned gas split ratio control element; and a second valve, which is located on the aforementioned gas flow control device. The gas supply device for the secondary side of the gas flow control device has the following processes: When processing the substrate, the second valve is closed and the first valve is opened to supply the gas to the gas supply piping, the branch piping and the gas flow control element located on the secondary side of the gas flow control device; The pressure sensor is used to detect that the pressure of the gas supply piping or the branch piping on the secondary side of the gas flow control device has reached the set pressure; The first valve is closed; and The first valve and the second valve are opened to supply the gas to the processing container. A gas supply method as claimed in claim 1, wherein the gas diversion ratio control unit variably controls the conductance of each of the plurality of gas diversion ratio control elements, thereby controlling the gas flow ratio supplied to the plurality of branch pipes. A gas supply method as claimed in claim 1 or 2, wherein a plurality of the aforementioned branch pipes are respectively connected to the corresponding processing areas of the aforementioned processing container, and the aforementioned gas flowing through each of the aforementioned branch pipes is supplied to the corresponding aforementioned processing area. As in claim 3, the gas supply method, wherein, the aforementioned gas comprises: a main gas; and an auxiliary gas, the aforementioned gas supply section comprises: a main gas supply section; and an auxiliary gas supply section, the aforementioned gas flow control device comprises: a gas flow control device for the main gas; and a gas flow control device for the auxiliary gas, the aforementioned gas supply piping comprises: a main gas supply piping through which the aforementioned main gas flows; and an auxiliary gas supply piping through which the aforementioned auxiliary gas flows, The branch piping comprises: a main gas branch piping, through which the main gas flows; and an auxiliary gas branch piping, through which the auxiliary gas flows. The secondary side of the second valve in the main gas branch piping is connected to the secondary side of the second valve in the auxiliary gas branch piping. The auxiliary gas is supplied to the main gas to generate two or more processing gases, and the two or more processing gases are respectively supplied to the corresponding processing areas of the processing container. A gas supply method as claimed in claim 4, wherein, it is detected that the pressure of the aforementioned main gas supply piping or the aforementioned main gas branch piping on the secondary side of the aforementioned gas flow control device for the main gas has reached the aforementioned set pressure, and it is detected that the pressure of the aforementioned auxiliary gas supply piping or the aforementioned auxiliary gas branch piping on the secondary side of the aforementioned gas flow control device for the auxiliary gas has reached the aforementioned set pressure, and after the aforementioned pressures of the two have reached the aforementioned set pressure, the aforementioned first valves located on the secondary sides of the aforementioned gas flow control device for the main gas and the aforementioned gas flow control device for the auxiliary gas are closed, the aforementioned first valves and the aforementioned second valves are opened to generate the aforementioned treated gas. A substrate processing device is provided with a gas supply device for supplying gas to a processing container for processing a substrate, and the substrate processing device is characterized by having: At least one gas flow control device is arranged in a gas supply piping from a gas supply section to the aforementioned processing container; A gas split ratio control section is composed of a gas split ratio control element, and the gas split ratio control element is respectively arranged in two or more branch pipings branched on the secondary side of the aforementioned gas flow control device, and has a conductance variable flow path that allows conductance to be freely variable; A first valve and a pressure sensor are located on the secondary side of the aforementioned gas flow control device and the primary side of the aforementioned gas split ratio control element; A second valve, Located on the secondary side of the aforementioned gas flow ratio control element; and control device, the aforementioned control device, which performs the control of "closing the aforementioned second valve and opening the aforementioned first valve when processing the aforementioned substrate, supplying the aforementioned gas to the aforementioned gas supply piping, the aforementioned branch piping, and the aforementioned gas flow ratio control element located on the secondary side of the aforementioned gas flow control device", performs the control of "closing the aforementioned first valve after the aforementioned pressure sensor detects that the pressure of the aforementioned gas supply piping or the aforementioned branch piping on the secondary side of the aforementioned gas flow control device has reached the set pressure", performs the control of "opening the aforementioned first valve and the aforementioned second valve, and supplying the aforementioned gas to the aforementioned processing container". A substrate processing device as claimed in claim 6, wherein the control device variably controls the conductance of each of the plurality of gas diversion ratio control elements for the gas diversion ratio control unit, and controls the gas flow ratio supplied to the plurality of branch pipes. A substrate processing device as claimed in claim 6 or 7, wherein a plurality of the aforementioned branch pipes are respectively connected to the corresponding processing areas of the aforementioned processing container, and the aforementioned gas flowing through each of the aforementioned branch pipes is supplied to the corresponding aforementioned processing area. As in claim 8, the substrate processing device, wherein, the aforementioned gas comprises: a main gas; and an auxiliary gas, the aforementioned gas supply section comprises: a main gas supply section; and an auxiliary gas supply section, the aforementioned gas flow control device comprises: a gas flow control device for the main gas; and a gas flow control device for the auxiliary gas, the aforementioned gas supply piping comprises: a main gas supply piping through which the aforementioned main gas flows; and an auxiliary gas supply piping through which the aforementioned auxiliary gas flows, The branch piping comprises: a main gas branch piping through which the main gas flows; and an auxiliary gas branch piping through which the auxiliary gas flows, The secondary side of the second valve in the main gas branch piping is connected to the secondary side of the second valve in the auxiliary gas branch piping, The auxiliary gas is supplied to the main gas to generate two or more processing gases, and the two or more processing gases are respectively supplied to the corresponding processing areas of the processing container. The substrate processing device as claimed in claim 9, wherein the control device performs the control of "closing the first valves of the gas flow control device for the main gas and the gas flow control device for the auxiliary gas after the pressure sensor detects that the pressure of the main gas supply pipe or the main gas branch pipe on the secondary side of the gas flow control device for the main gas has reached the set pressure, and detects that the pressure of the auxiliary gas supply pipe or the auxiliary gas branch pipe on the secondary side of the gas flow control device for the auxiliary gas has reached the set pressure", and then performs the control of "opening the first valves and the second valves to generate the processing gas".

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