Plasma processing equipment

Abstract

The present invention provides a plasma processing apparatus that meets the explosion-proof requirements of safety standards, enabling stable supply of vaporized raw material gas and maintaining processing efficiency. [Solution] The plasma processing unit includes a processing gas supply pipe through which a processing gas supplied to the processing chamber flows, and a vaporization unit connected to the processing gas supply pipe. The vaporization unit includes a processing gas supply line connected to the processing gas supply pipe, a liquid raw material supply line through which a liquid raw material flows, a vaporizer that vaporizes the liquid raw material and sends the generated raw material gas to the processing gas supply line, a flow controller that adjusts the flow rate of the raw material gas, and one or both of a first bracket that surrounds the outer circumference of the liquid raw material supply line upstream of the vaporizer and transfers heat from the vaporizer to the liquid raw material supply line for heating, and a second bracket that surrounds the outer circumference of the reaction gas supply line downstream of the flow controller and transfers heat from the flow controller to the reaction gas supply line for heating.

Description

Technical Field

[0001] The present disclosure relates to a plasma processing apparatus.

Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2017-143186 (Patent Document 1) discloses performing an atomic layer level etching process on a layer on a semiconductor wafer in a vacuum processing apparatus used for manufacturing a semiconductor device. Specifically, first, a step of supplying and adhering active species (radicals) of a processing gas formed using plasma to the upper surface of a semiconductor wafer as a sample to generate a product layer on the surface is performed. Then, a step of irradiating the wafer with electromagnetic waves having a wavelength including infrared rays from a lamp arranged in a ring shape surrounding the region above the wafer to desorb and volatilize the product layer is performed, and by removing the product layer formed to a thickness equivalent to an atomic layer, the etching process is performed.

[0003] In such a technique, for a wafer placed on a sample stage (stage) arranged in a processing chamber inside a vacuum container, (1) a step of forming a layer of reaction products by radicals and (2) a step of removing the reaction layer by heating irradiated with electromagnetic waves including infrared rays are performed. Regarding the reaction layer formation step of (1), first, a processing gas is supplied to a radical generation space above the processing chamber, and radicals are formed by activating the gas. The formed radical particles are supplied to the upper surface of the wafer placed in the processing chamber through a gas introduction pipe whose upper and lower processing chambers are communicated, and a reaction layer is formed. Regarding the reaction layer removal step of (x), it is performed after (1), infrared light is irradiated from a lamp arranged above the wafer, the product on the upper surface of the wafer is vaporized, and the reaction layer is removed. These steps are repeated alternately, and the film to be processed on the wafer surface is removed.

[0004] In the manufacturing process of semiconductor devices, when the raw material for the gas used as a processing gas is a liquid with a low vapor pressure, a method is applied in which the liquid raw material is vaporized using a vaporizer to generate a raw material gas to be supplied into a vacuum chamber and used in an etching apparatus. For this reason, plasma processing apparatuses using various vaporizers have been devised. Furthermore, Japanese Patent Application Publication No. 2014-236018 (Patent Document 2) describes a technique for supplying a desired flow rate by vaporizing a liquid material in a container and supplying a material gas at a set flow rate to a chamber while controlling the gas supply pressure to a desired pressure with a flow rate control device. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2017-143186 [Patent Document 2] Japanese Patent Publication No. 2014-236018 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the above-mentioned conventional technology may have problems because it did not adequately consider the following points.

[0007] Conventionally, when applying a method to a plasma processing apparatus in which liquid raw materials are vaporized in a vaporizer along the gas supply path, and the supply pressure of the raw material gas is controlled to a desired pressure by a flow controller, the liquid raw material on the primary side (upstream side) of the vaporizer is sometimes heated with a resistance heater or heat transfer medium in order to improve vaporization efficiency. Furthermore, the liquid raw material introduced into the vaporizer is an incompressible fluid and undergoes thermal expansion due to temperature. Therefore, closing a valve installed upstream of the vaporizer directly leads to a pressure increase, which exceeds the pressure tolerance of the components and poses a risk of component damage. Thus, measures are needed to reduce the temperature difference between the vaporizer and the liquid raw material on the primary side of the vaporizer. For these two reasons, it is necessary to preheat the liquid raw material on the primary side of the vaporizer.

[0008] Furthermore, to prevent reliquefaction, the raw material gas in the gas path on the secondary (downstream) side of the vaporizer may be heated with a resistance heater or heat transfer medium. If reliquefaction of the raw material gas occurs, liquid remains in the supply piping to the processing chamber, causing problems such as blockage of the flow path and valve sticking due to the products. In addition, the flow rate of the gas flowing through the path becomes unstable due to this residual liquid, leading to increased exhaust time and worsened maintainability, which can reduce the yield of plasma processing.

[0009] For the reasons stated above, in semiconductor device manufacturing equipment, it is preferable to maintain the temperature of the gas generated from the liquid raw material above its boiling point in the gas supply path to prevent liquefaction. However, liquid raw materials used in plasma processing equipment are often flammable, and in conventional technology, from an explosion-proof standpoint, it is difficult to heat the gas using electric heating wires that could act as ignition sources in the primary piping, including the fittings of the vaporizer that use flammable materials, or in the secondary (downstream) piping of the flow controller, resulting in a problem of reduced processing yield.

[0010] The purpose of this disclosure is to provide a plasma processing apparatus that can stably supply the flow rate of vaporized raw material gas, or improve the yield and efficiency of processing, in a plasma processing apparatus that generates a raw material gas by vaporizing a liquid raw material in a vaporizer and supplies the raw material gas at a set flow rate to a processing chamber using a flow rate controller.

[0011] Other challenges and novel features will become apparent from the description and accompanying drawings in this specification. [Means for solving the problem]

[0012] A brief overview of some of the representative disclosures is as follows:

[0013] According to one embodiment, the plasma processing apparatus is A processing chamber is located inside a vacuum container, with a processing gas supplied to the inside, and the wafer to be processed is placed inside. A processing gas supply pipe is connected at one end to the vacuum container, through which the processing gas flows. It includes a vaporization unit connected to the other end of the processing gas supply piping, The aforementioned vaporization unit section is, A processing gas supply line connected to the other end of the processing gas supply piping, A liquid raw material supply line through which liquid raw materials flow, A vaporizer connected to the liquid raw material supply line, which vaporizes the liquid raw material to generate a raw material gas and sends the generated raw material gas to the processing gas supply line, A flow controller connected to the aforementioned processing gas supply line and adjusting the flow rate of the aforementioned raw material gas, The device comprises one or both of the following: a first bracket that surrounds the outer circumference of the liquid raw material supply line upstream of the vaporizer and transfers heat from the vaporizer to the liquid raw material supply line for heating; and a second bracket that surrounds the outer circumference of the processing gas supply line downstream of the flow controller and transfers heat from the flow controller to the processing gas supply line for heating. [Effects of the Invention]

[0014] According to the above-described embodiment, it is possible to provide a plasma processing apparatus that satisfies explosion-proof conditions in safety standards and can improve the flow rate stable supply of vaporized source gas and the processing efficiency.

Brief Description of the Drawings

[0015] [Figure 1] FIG. 1 is a diagram schematically showing an outline of the configuration of a plasma processing apparatus according to an embodiment of the present disclosure. [Figure 2A] FIG. 2A is a top view and a side view schematically showing the relationship between the vaporizer and the flow rate controller provided in the integrated liquid gas box of the present embodiment shown in FIG. 1, and the liquid source gas supply line and the processing gas supply line. [Figure 2B] FIG. 2B is a cross-sectional view taken along line B-B shown in FIG. 2A, and is a cross-sectional view showing the positional relationship between the vaporizer and the flow rate controller provided in the integrated liquid gas box of the embodiment and the bracket. [Figure 2C] FIG. 2C is a side view seen from the C direction shown in FIG. 2A, and is a side view seen from the vaporizer side showing the positional relationship between the vaporizer and the flow rate controller provided in the integrated liquid gas box of the embodiment, the bracket, and the elastic member. [Figure 3] FIG. 3 is a diagram schematically showing a bracket according to an embodiment.

Modes for Carrying Out the Invention

[0016] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the description of the drawings, the same parts are denoted by the same reference numerals. However, in the following description, the same components may be denoted by the same reference numerals and repeated description may be omitted. Note that the drawings may be schematically represented compared to the actual aspect for the sake of clearer explanation, but are merely examples and do not limit the interpretation of the present disclosure.

[0017] In the present disclosure, in order to indicate directions, the directions indicated by the x-axis, y-axis, and z-axis shown on the drawing may be used. Further, the "z-axis plus direction" may be referred to as "upward", and the "z-axis minus direction" may be referred to as "downward". Also, the upstream or the upstream side means the direction of the liquid or gas supply source or the direction close to the supply source. The downstream or the downstream side means the side away from or the far direction from the liquid or gas supply source.

Example

[0018] Hereinafter, referring to FIGS. 1 to 5, Example 1 (First Embodiment) of the present disclosure will be described.

[0019] Referring to FIG. 1, the configuration of the plasma processing apparatus will be described.

[0020] FIG. 1 is a diagram schematically showing the configuration of a plasma processing apparatus 100 according to the first embodiment. In the first embodiment, a dry etching apparatus is taken as the type of the plasma processing apparatus 10 at

[0021] As shown in FIG. 1, the dry etching apparatus as the plasma processing apparatus 100 includes a processing chamber 104 in which a wafer 1020 is disposed inside a vacuum chamber 101, a discharge chamber 102 in which plasma is formed above and inside the processing chamber 104, and a lamp 1021 disposed around a passage through which gas and plasma particles in the discharge chamber 102 communicate between the processing chamber 104 and the discharge chamber 102 above the processing chamber 104 (in the z-axis plus direction).

[0022] In such a dry etching apparatus 100, first, a step (adsorption step) of supplying reactive particles formed in the discharge chamber 102 to the film to be processed on the upper surface of the wafer 1020 in the processing chamber 104, adsorbing the particles to the film to be processed, and reacting them to form a layer of reaction products is performed. Then, next, a step (desorption step) of heating the wafer 1020 to set it to an appropriate temperature and desorbing or vaporizing the layer of reaction products from the surface of the wafer 1020 to remove it is performed. Thereby, isotropic etching can be performed on the film to be processed.

[0023] The plasma processing apparatus 100 shown in Figure 1 is broadly composed of a vacuum vessel 101, a plasma forming section (ICP coil 109, matching unit 110, high-frequency power supply 111) arranged around its outer periphery to generate an electric field inside the vacuum vessel 101 and form plasma, and an exhaust section (vacuum pump 1018, exhaust volume control valve 1019) located below the vacuum vessel 101 (in the negative z-axis direction) to evacuate the inside of the vacuum vessel 101 and reduce the pressure.

[0024] The vacuum vessel 101 comprises a discharge chamber 102, a processing chamber 104, a passage 106, and a dispersion plate 107, with an IR lamp unit 105 positioned above the processing chamber 104. The discharge chamber 102 is a portion of the upper part of the vacuum vessel 101, enclosed by a cylindrical side wall, and is a discharge chamber (discharge section) where plasma 1011 is formed internally. The processing chamber 104 is a portion of the lower part of the vacuum vessel 101, enclosed by a cylindrical internal space, and is the part that surrounds a sample stage 103 on which a wafer 1020 is placed. The IR lamp unit 105 is positioned above the processing chamber 104, surrounding the discharge chamber 102, and heats the wafer 1020 placed on the sample stage 103 by irradiating it with infrared light from above. The passage 106 is a passage connecting the discharge chamber 102 and the processing chamber 104, and is a cylindrical passage surrounded by the IR lamp unit 105. The dispersion plate 107 is placed inside the passage 106 and is composed of a disc-shaped dielectric with multiple through-holes through which active particles (active species) such as radicals generated in the plasma 1011 pass towards the processing chamber 104.

[0025] Furthermore, the central axis of the passage 106 and the dispersion plate 107 in the vertical direction coincides with the center of the circular upper surface of the sample stage 103, or is positioned at a location that is so close to it that it can be considered as such. The dispersion plate 107 is located at the lower end of the passage 106 and is positioned above the sample stage 103 and opposite to the sample stage 103.

[0026] The processing chamber 104 and discharge chamber 102 of the plasma processing apparatus 100 are cylindrical spaces, and their central axes are located on the same axis as the central axis of the passage 106, or at a position that is so close to it as to be considered the same axis. The processing chamber 104 and the discharge chamber 102 are separated by a circular dispersion plate 107, and the spaces above and below the dispersion plate 107 are connected through a plurality of through holes arranged concentrically in the dispersion plate 107.

[0027] The discharge chamber 102 is located inside a cylindrical quartz container 108, which is a container made of a material such as quartz that is transparent to light from the plasma 1011 and is connected to the processing chamber 104, with the inside maintained at a predetermined vacuum pressure. An ICP (Inductively Coupled Plasma) coil 109, which acts as a high-frequency induction coil, is arranged on the outside of the quartz container 108 so as to surround the side wall of the quartz container 108. The ICP coil 109 is electrically connected to a high-frequency power supply 111 via a matching unit 110. The ICP coil 109 generates a high-frequency magnetic field or electric field by the high-frequency power supplied from the high-frequency power supply 111, causing the plasma 1011 to form inside the discharge chamber 102.

[0028] A circular top plate 1014 is positioned above the discharge chamber 102. Below the top plate 1014, a shower plate 1015 is positioned connected to the top plate 1014 with a gap in between. The processing gas is supplied from at least one gas supply pipe 1016 connected to the top plate 1014 and introduced into the discharge chamber 102 from above through a gap between the top plate 1014 and the shower plate 1015, via multiple through-holes located in the center of the shower plate 1015. In Figure 1, three gas supply pipes 1016 are depicted as an example.

[0029] Atoms or molecules of the processing gas are excited by the electric or magnetic field generated by the ICP coil 109, and are ionized or dissociated, generating plasma 1011 in the discharge chamber 102 by the ICP discharge method. In the first embodiment, the high-frequency power supplied to the ICP coil 109 is in the frequency band of several tens of MHz. For example, the frequency of the high-frequency power is 13.56 MHz.

[0030] In the first embodiment, the state of the plasma 1011 is configured to be observed by optical methods. The light emitted from the plasma 1011 generated in the discharge chamber 102 is detected using an optical detector such as an OES (Optical Emission Spectroscopy) attached to the discharge chamber 102. In the first embodiment, a spectrometer 1012 is attached to the upper part of the side wall of the outer circumference of the quartz container 108 surrounding the discharge chamber 102, with its light-receiving surface facing the inside of the discharge chamber 102. The light emitted from the generated plasma 1011 is received from the inside through the quartz container 108 and the light-receiving surface of the spectrometer 1012 on the discharge chamber 102 side. The spectrometer 1012 is an optical detector.

[0031] The spectrometer 1012 separates (spectroscopy) the light emitted from the received plasma 1011 into light of multiple wavelengths within a predetermined range, and detects the intensity of light at each wavelength. The spectrometer 1012 is connected to the controller 1013 of the plasma processing apparatus 100 via wired or wireless communication, and the output from the spectrometer 1012 is transmitted to the controller 1013. The controller 1013 calculates the intensity of light emitted at each wavelength from the received signal according to a pre-installed software algorithm, and can detect the state of the plasma 1011 in the discharge chamber 102 and the state of the inner wall surface of the quartz container 108 based on the result of comparing the intensity value or the magnitude of its change with a reference value.

[0032] Furthermore, a sealing member such as an O-ring is positioned between the lower surface of the outer edge of the circular top plate 1014 and the upper surface of the upper end of the side wall of the cylindrical quartz container 108 surrounding the discharge chamber 102. The sealing member deforms as it is connected and fastened, or as the discharge chamber 102 and the processing chamber 104 are evacuated and depressurized by the operation of the exhaust unit, thereby hermetically sealing the space between the inside and outside of the discharge chamber 102. In this way, the quartz container 108 surrounding the discharge chamber 102 and the top plate 1014 constitute a vacuum container 101.

[0033] The processing gas is supplied, for example, through piping 2016 that extends from gas supply sources GSS for each type of gas located below the floor of the building where the plasma processing apparatus 100 is installed, and is connected to the vacuum vessel 101 via piping 1016. Between piping 2016 and piping 1016, there is a box-shaped integrated gas box 112 which has multiple pipelines separated by multiple types of gas and flow controllers 202 that are placed on these pipelines to adjust the flow rate, speed, and pressure of each type of gas. Piping 1016 can be referred to as processing gas supply piping.

[0034] In this embodiment, at least one raw material gas is supplied through a pipe 1016 connected to the vacuum vessel 101 via a pipe 3016 extending from a liquid gas supply source (liquid raw material supply source) LSS. Between pipe 3016 and pipe 1016, a box-shaped integrated liquid gas box 113 is arranged, which has a vaporizer 201 that vaporizes the liquid gas (liquid raw material) into a raw material gas and a flow controller 202 that adjusts the flow rate, speed, and pressure of the vaporized raw material gas. The vaporizer 201 and the flow controller 202 can be collectively referred to as a vaporization unit, and in the example in Figure 1, pipes 2016 and 3016 are connected to the integrated liquid gas box 113 equipped with the vaporization unit.

[0035] Inside the gas collection box 112 and the liquid gas collection box 113, the pipelines supplying each processing gas merge and are consolidated into multiple gas supply pipes 1016, which extend to the outside of the gas collection box 112 and the liquid gas collection box 113.

[0036] The flow of gas introduced into the discharge chamber 102 is regulated by opening or closing on / off valves 1017 located on these gas supply pipes 1016. In the first embodiment, the process gas used is a combustible gas, a combustion-supporting gas, a mixture thereof, or a mixture thereof diluted with an inert gas. The inert gas can be, for example, nitrogen (N2) gas, as shown in Figure 1.

[0037] Below the processing chamber 104, a vacuum pump 1018, such as a turbomolecular pump, is positioned and connected to evacuate the gas inside the processing chamber 104 and reduce the pressure. The vacuum pump 1018 is connected to the vacuum vessel 101, which forms the bottom of the processing chamber 104, via an exhaust volume control valve 1019 that adjusts the exhaust flow rate or speed by increasing or decreasing the area of ​​the flow path.

[0038] Furthermore, the processing chamber 104 is equipped with a sample stage 103 having a mounting surface for the wafer 1020. The cylindrical sample stage 103 has a central axis that coincides with, or approximates to, the vertical central axis of the discharge chamber 102, the processing chamber 104, and the passage 106 that connects the discharge chamber 102 and the processing chamber 104. In addition, the cylindrical sample stage 103 has a base material made of a cylindrical conductive material such as metal inside, and a refrigerant channel (not shown) for circulating a refrigerant to adjust the temperature of the wafer 1020 on the sample stage 103 is arranged inside the base material.

[0039] Above the processing chamber 104, an IR lamp unit 105 is positioned in a ring shape surrounding the outer perimeter of the passage 106. The IR lamp unit 105 includes three IR lamps 1021 arranged in a ring shape at three different radial positions extending outward from the central axis of the cylindrical processing chamber 104 or passage 106, and a reflector 1022 positioned in a ring shape above the IR lamps 1021 to reflect the IR light, which is electromagnetic wave emitted from the IR lamps 1021, toward the processing chamber 104 or the mounting surface of the sample stage 103 and the wafer 1020 placed thereon. Furthermore, below the IR lamps 1021, there is an IR light transmission window 1023 that covers the upper part of the processing chamber 104 and forms the inner side wall of the cylindrical passage 106, and is made of a material such as quartz through which IR light can pass.

[0040] The IR lamp 1021 of the first embodiment uses three circular lamps arranged concentrically from the central axis at three different radial positions. The electromagnetic waves emitted from each IR lamp 1021 mainly consist of light in the visible light to infrared light region (referred to here as IR light). The IR lamp 1021 is connected to a lamp power supply 1024 that supplies power to it, and a high-frequency cut filter 1025 is placed between the two to prevent noise from the high-frequency power supplied to the ICP coil 109 from reaching the lamp power supply 1024 through the IR lamp.

[0041] Each of the three IR lamps 1021, which are arranged concentrically at their respective radial positions from the central axis position in the vertical direction of the processing chamber 104 and the passage 106, receives individually adjusted power from the lamp power supply 1024, and the intensity or amount of IR light emitted is independently adjusted. The lamp power supply 1024 is communicably connected to the controller 1013, which adjusts the operation of the plasma processing apparatus 100, and upon receiving a command signal from the controller 1013, the lamp power supply 1024 adjusts the operation of each of the three IR lamps 1021, as well as the amount and intensity of IR light emitted, based on the command signal. In the first embodiment, since each of the three IR lamps 1021, which are arranged concentrically around the central axis, is configured to be able to adjust its operation independently, when heating the wafer 1020 by emitting IR light, it is possible to adjust the temperature distribution in the radial direction of the wafer 1020 to a desired temperature distribution. As a result, it is possible to reduce variations in the circumferential temperature distribution of the wafer 1020 and approach a more uniform temperature distribution.

[0042] Above the IR lamp 1021, a reflector 1022 is positioned to reflect the radially emitted IR light downwards (towards the sample stage 103 or wafer 1020). Furthermore, the ring-shaped ceiling surface of the processing chamber 104 below the IR lamp 1021 and the inner circumferential side walls of the passage 106 connected thereto are made of the inner surface of a quartz IR light-transmitting window 1023 that allows IR light to pass through. This arrangement minimizes or eliminates areas where the IR light radiated from the three lamps of the IR lamp 1021 toward the interior of the processing chamber 104 and the surface of the wafer 1020 on the sample stage 103 is blocked. In particular, the lower part of the inner circumferential side walls of the passage 106 and the inner circumferential edge of the ring-shaped ceiling surface of the processing chamber 104 are also made of the same light-transmitting quartz material. This allows IR light from the IR lamp 1021, which is radiated toward the center of the processing chamber 104 or passage 106, to reach the wafer 1020 evenly, making it possible to efficiently heat the wafer 1020.

[0043] The inner circumference of the ring-shaped IR lamp unit 105 has a cylindrical shape with a central axis in the vertical direction, and constitutes a part of the passage 106. Particles in the plasma 1011 formed in the discharge chamber 102 located above it flow through the passage 106 toward the processing chamber 104 below. At the bottom of the passage 106 is a dispersion plate 107 made of a dielectric material such as quartz, which has a disc shape with a diameter slightly smaller than the diameter of the passage 106. The dispersion plate 107 is positioned opposite the center of the mounting surface of the sample stage 103 or the upper surface of the wafer 1020 placed thereon. Multiple through holes are arranged in the central part of the dispersion plate 107, and these through holes shield ions and electrons generated in the plasma 1011 while allowing neutral particles and radicals to pass through and be introduced into the processing chamber 104.

[0044] The configuration example of the accumulated liquid gas box 113 will be described below using Figures 2A, 2B, and 2C. Figure 2A schematically shows the relationship between the vaporizer 201 and flow controller 202, the liquid raw material gas supply line 204 and the processing gas supply line 205, which are included in the accumulated liquid gas box 113 of this embodiment shown in Figure 1. Figure 2B is a cross-sectional view along the line BB shown in Figure 2A, and is a cross-sectional view of the figure showing the positional relationship between the vaporizer 201 and flow controller 202 and the bracket 207, which are included in the accumulated liquid gas box 113 of this embodiment. Figure 2C is a side view seen from direction C shown in Figure 2A, and is a side view showing the positional relationship between the vaporizer 201 and flow controller 202, the bracket 2071 and the elastic member 2121, which are included in the accumulated liquid gas box 113 of this embodiment.

[0045] As shown in Figure 2A, the liquid gas collection box 113 is equipped with a liquid raw material gas supply line (also called a liquid raw material supply line) 204, a vaporizer 201, a processing gas supply line 205, and a flow rate controller 202. The vaporizer 201 and the flow rate controller 202 are arranged in the liquid raw material gas supply line 204 and the processing gas supply line 205 in the direction of the flow of the raw material gas.

[0046] The liquid raw material gas supply line 204 is connected to piping 3016 to which the liquid supply source LSS is connected, and the liquid raw material is supplied from the liquid supply source LSS. The vaporizer 201 is connected to the liquid raw material gas supply line 204 and can vaporize the liquid raw material flowing inside the liquid raw material gas supply line 204 to produce a raw material gas.

[0047] The vaporizer 201 is connected to the processing gas supply line 205 and supplies vaporized raw material gas to the processing gas supply line 205. The flow controller 202 is connected to the processing gas supply line 205 and adjusts the flow rate (flow rate), speed, and pressure of the raw material gas supplied to the processing gas supply line 205.

[0048] One end of the processing gas supply line 205 is connected to the vacuum chamber 101 via the gas supply pipe 1016. This supplies processing gas to the processing chamber 104 where the wafers 1020 to be processed are placed. The other end of the processing gas supply line 205 is connected to the vaporizer 201. The vaporizer 201 and the flow controller 202 are fixed and positioned on the accumulating bracket 203 located inside the accumulating liquid gas box 113.

[0049] As shown in Figures 2A and 2B, a block (also referred to as the first block) 2091 is placed at the bottom of the vaporizer 201. A block (also referred to as the second block) 2092 is placed at the bottom of the flow controller 202. A liquid raw material gas supply line 204 is placed inside block 2091. A processing gas supply line 205 is placed inside block 2092. The bottom surfaces of block 2091 and block 2092 are provided to be in contact with the surface of the accumulating bracket 203. The accumulating bracket 203 can be called a third bracket with heat transfer properties. Heaters (also referred to as the first heater) 2101 and heaters (also referred to as the second heater) 2102 are placed inside blocks 2091 and 2092 to heat the liquid raw material gas supply line 204 and the processing gas supply line 205 and improve vaporization efficiency, thereby uniformly heating the entire blocks 2091 and 2092.

[0050] Furthermore, a vaporization chamber 211 is provided inside the vaporizer 201. The vaporization chamber 211 is connected to a liquid raw material gas supply line 204 and a processing gas supply line 205. The inlet IN of the vaporization chamber 211 is connected to the liquid raw material gas supply line 204, and the outlet OUT of the vaporization chamber 211 is connected to the processing gas supply line 205. The inlet IN of the liquid raw material gas supply line 204 in the vaporization chamber 211 has an orifice structure, and the liquid raw material is introduced radially. In the vaporization chamber 211, the liquid raw material introduced to the orifice flat surface and the diamond flat surface vaporizes when the liquid raw material reaches a low pressure state below the vapor pressure due to a rapid pressure drop, generating bubbles, and is continuously vaporized as raw material gas by the thermal effect of the heater 2101.

[0051] Plate-shaped members covering the upper, left, and right outer surfaces of the liquid raw material gas supply line 2041 and the vaporizer joint 206, located upstream of the vaporizer 201 through which the liquid raw material gas flows, are bent at approximately right angles at their ends or connected integrally. A box-shaped bracket (also referred to as the first bracket) 2071, which has no end faces, is positioned on the integrating bracket 203, covering the lower side and both axial ends of the liquid raw material gas supply line 2041. The bracket 2071 may be attached in contact with the surface of the vaporizer 201. Alternatively, the bracket 2071 may be attached in contact with the surface of a heat-conducting member that is in contact with the surface of the vaporizer 201. The bracket 2071 is thermally connected to the vaporizer 201 and the inner liquid gas supply line 2041, and surrounds the outer circumference of the liquid raw material gas supply line 2041 upstream of the vaporizer 201, thereby transferring heat from the vaporizer 201 to the liquid raw material gas supply line 2041 for heating.

[0052] As a result, the heat from block 2091, heated by heater 2101, is transferred to bracket 2071 via integrated bracket 203, thereby heating the liquid raw material gas supply line 2041 and vaporizer fitting 206. Therefore, preheating of the liquid raw material on the primary side of vaporizer 201 is possible, making it possible to reduce the temperature difference between vaporizer 201 and the liquid raw material on its primary side (upstream side).

[0053] Furthermore, the heat from block 2091 heated by heater 2101 and the heat from block 2092 heated by heater 2102 can heat the processing gas supply line 205 connected to the outlet OUT of the vaporization chamber 211, as well as the processing gas supply line 205 between the flow controller 202 and the vaporizer 201, via the integrating bracket 203. As a result, the raw material gas on the secondary side (downstream side) of the vaporizer and the primary side (upstream side) of the flow controller 202 can also be heated to a temperature higher than the boiling point of the raw material gas. This prevents the reliquefaction of the raw material gas.

[0054] A bracket (also referred to as a second bracket) 2072, which has a shape that covers the upper, left, and right outer surfaces of the processing gas supply line 2051 and the flow controller joint 208 located downstream of the flow controller 202, is placed on the integration bracket 203. The bracket 2072 may be attached in contact with the surface of the flow controller 202. Alternatively, the bracket 2072 may be attached in contact with the surface of a heat-conducting member that is in contact with the surface of the flow controller 202. The bracket 2072 in this embodiment has the same shape and configuration as the bracket 2071 and is provided to surround the outer surface of the processing gas supply line 2051 downstream of the flow controller 202 and transfer heat from the flow controller 202 to the processing gas supply line 2051 for heating.

[0055] As a result, the heat from block 2092, heated by heater 2102, is transferred to bracket 2072 via integration bracket 203, thereby heating the processing gas supply line 2051 and the flow controller joint 208. Consequently, the raw material gas on the secondary side (downstream side) of flow controller 202 can also be heated to a temperature higher than the boiling point of the raw material gas. This prevents the reliquefaction of the raw material gas.

[0056] As shown in Figures 2B and 2C, the bracket 2071 has an elastic member 2121 positioned between it and the outer periphery wall surface of the liquid raw material gas supply line 2041, and in contact with both. The bracket 2072 has an elastic member 2122 positioned between it and the outer periphery wall surface of the processing gas supply line 2051, and in contact with both.

[0057] The elastic member 2121 is positioned between the bracket 2071 and the outer periphery wall surface of the liquid raw material gas supply line 2041, and is configured to be in contact with both. Furthermore, the elastic member 2121 is positioned at three or more locations on the inner side of the inner wall surface of the bracket 2071, on the top surface and side surfaces (left side and right side) of the outer surface of the liquid raw material gas supply line 2041. In other words, three or more elastic members 2121 are provided. The integrated bracket 203, bracket 2071, and elastic member 2121 are made of, for example, aluminum, which has high thermal conductivity and heat transfer properties. In addition, to improve heat transfer, an insulating member may be placed on the outer surface of the bracket 2071.

[0058] In other words, the bracket 2071 has an upper surface US, a left side surface LS, and a right side surface RS, and is configured to cover the upper, left, and right sides of the outer circumference of the liquid raw material gas supply line 2041 and the vaporizer fitting 206 with these upper surface US, left side surface LS, and right side surface RS.

[0059] Although not shown in the diagram, the elastic member 2122, like the elastic member 2121, is positioned between the bracket 2072 and the outer periphery wall surface of the processing gas supply line 2051, and is in contact with both. Furthermore, the elastic member 2122 is positioned at three or more locations on the outer surface of the processing gas supply line 2051, on the top surface and the sides (left side and right side). In other words, three or more elastic members 2122 are provided. The bracket 2072 and the elastic member 2122 are made of, for example, aluminum, which has high thermal conductivity and good heat transfer properties. In addition, to improve heat transfer, an insulating member may be placed on the outer surface of the bracket 2072.

[0060] In other words, bracket 2072, like bracket 2071, has an upper surface US, a left side surface LS, and a right side surface RS, and is configured so that these upper surface US, left side surface LS, and right side surface RS can cover the upper, left, and right sides of the outer circumference of the processing gas supply line 2051 and the flow control joint 208.

[0061] Here, the integrating bracket 203, bracket 2071, and elastic member 2121 are composed of heat-conducting materials, and the heat from the heater 2101 located inside the vaporizer 201 is transferred to the integrating bracket 203, bracket 2071, and elastic member 2121 via the block 2091. In other words, the heat from the integrating bracket 203 is transferred to the left side LS and right side RS of bracket 2071, and the heat from the left side LS and right side RS is transferred to the top surface US of bracket 2071. Furthermore, the heat from the left side LS and right side RS and the heat from the top surface US are transferred to the outer periphery wall surface of the liquid raw material gas supply line 2041 via the elastic member 2121. This allows the vaporizer joint 206 and the liquid raw material gas supply lines 204 and 2041 to be heated.

[0062] Furthermore, the integrating bracket 203, bracket 2072, and elastic member 2122 are composed of heat-conducting materials, and the heat from the heater 2102 located inside the flow controller 202 is transferred to the integrating bracket 203, bracket 2072, and elastic member 2122 via the block 2092. In other words, the heat from the integrating bracket 203 is transferred to the left side LS and right side RS of bracket 2072, and the heat from the left side LS and right side RS is transferred to the top surface US of bracket 2072. In addition, the heat from the left side LS and right side RS and the heat from the top surface US are transferred to the outer periphery wall surface of the processing gas supply line 2051 via the elastic member 2122. This allows the processing gas supply lines 205 and 2051, including the flow controller joint 208, to be heated.

[0063] Figure 3 is a schematic diagram showing bracket 2071 according to an embodiment. Bracket 2072 has a similar configuration to bracket 2071.

[0064] The bracket 2071 has an upper surface US, a left side surface LS, and a right side surface RS, and is shaped to cover the upper, left, and right sides of the outer circumference of the liquid raw material gas supply line 2041 and the vaporizer joint 206 located upstream of the vaporizer 201 with the upper surface US, left side surface LS, and right side surface RS. It also has three protrusions 301 for arranging the elastic member 2121. The means for arranging the elastic member 2121 on the bracket 2071 may be to weld it directly to the bracket 2071.

[0065] Although not shown in the figures, bracket 2072, like bracket 2071, has an upper surface US, a left side surface LS, and a right side surface RS, and is shaped to cover the upper, left, and right sides of the outer circumference of the processing gas supply line 2051 and the flow controller joint 208 located downstream of the flow controller 202 with its upper surface US, left side surface LS, and right side surface RS. It also has a projection 301 for arranging the elastic member 2122. Alternatively, the means for arranging the elastic member 2122 on bracket 207 may be to weld it directly to bracket 2072.

[0066] Since an elastic member with heat transfer properties is provided between the brackets (2071, 2072) and the outer wall surface of the piping of the liquid raw material gas supply line 2041 and the processing gas supply line 2051, heat from the brackets (2071, 2072) can be efficiently transferred to the piping of the liquid raw material gas supply line 2041 and the processing gas supply line 2051.

[0067] By using the above configuration, the accumulation bracket 203, brackets 2071, 2072, and elastic members 2121, 2122, which are composed of heat-conducting members that receive heat from heaters 2101, 2102 located inside the vaporizer 201 and flow controller 202, can heat the liquid raw material gas supply lines 204, 2041 including the vaporizer joint 206 and the processing gas supply lines 205, 2051 including the flow controller joint 208, without having a heat source that could act as an ignition source in a location within the accumulation liquid gas box 113 where leakage is a concern.

[0068] This enables a plasma processing apparatus 100 that vaporizes flammable liquid materials (liquid raw materials) to provide a stable gas supply without reliquefaction and suppress temperature changes of the liquid material. As a result, it is possible to provide a plasma processing apparatus 100 that meets the explosion-proof conditions of safety standards, enabling measures to prevent internal pressure rise and improve vaporization efficiency, thereby improving the stable flow rate supply of vaporized raw material gas and the efficiency of plasma processing.

[0069] Furthermore, by covering the vaporizer fitting 206 with the bracket 2071, even if liquid leakage occurs, the scattering of liquid material can be prevented, and the leaked liquid can be captured inside the drain pan (not shown) located at the bottom of the vaporization unit.

[0070] The disclosures made by the Disclosers have been described in detail based on their embodiments, but the disclosures are not limited to the embodiments described above and can be modified in various ways without departing from their essence. [Explanation of Symbols]

[0071] 100... Plasma processing equipment 101...Vacuum container 102...discharge chamber 103... Sample stage 104... Processing Room 105...IR lamp unit 106…Passageway 107...dispersion plate 108...Quartz container 109... ICP coil 110...matching box 111...High frequency power supply 112...Gas collection box 113...Collecting liquid gas box 1011…Plasma 1012...Spectrometer 1013...Controller 1014... Tabletop 1015... Shower plate 1016...Gas supply pipe (processed gas supply piping) 1017... On / off valve 1018... Vacuum pump 1019... Displacement adjustment valve 1020… Wafer 1021...IR lamp 1022...Reflector 1023...IR light transmission window 1024...Power supply for lamps 1025... High-frequency cut filter 201... Vaporizer 202…Flow controller 203…Integrated bracket 204, 2041…Liquid gas supply line (Liquid raw material supply line) 205, 2051… Processing gas supply lines 206... Carburetor fitting 2071, 2072… brackets 208…Flow controller fitting Blocks 2091, 2092, etc. 2101, 2102... Heater 211... Vaporization chamber 2121, 2122… Elastic members 301...Protrusion

Claims

1. A processing chamber is located inside a vacuum container, with a processing gas supplied to the inside, and the wafer to be processed is placed inside. A processing gas supply pipe is connected at one end to the vacuum container, through which the processing gas flows. It includes a vaporization unit connected to the other end of the processing gas supply piping, The aforementioned vaporization unit section is, A processing gas supply line connected to the other end of the processing gas supply piping, A liquid raw material supply line through which liquid raw materials flow, A vaporizer connected to the liquid raw material supply line, which vaporizes the liquid raw material to generate a raw material gas and sends the generated raw material gas to the processing gas supply line, A flow controller connected to the aforementioned processing gas supply line and adjusting the flow rate of the aforementioned raw material gas, A plasma processing apparatus comprising: a first bracket that surrounds the outer circumference of the liquid raw material supply line upstream of the vaporizer and transfers heat from the vaporizer to the liquid raw material supply line for heating; and one or both of the second brackets that surround the outer circumference of the processing gas supply line downstream of the flow controller and transfer heat from the flow controller to the processing gas supply line for heating.

2. A plasma processing apparatus according to claim 1, A plasma processing apparatus in which, when the vaporization unit has the second bracket, the temperature of the raw material gas inside the processing gas supply line surrounded by the second bracket is raised to a level higher than the boiling point of the raw material gas.

3. A plasma processing apparatus according to claim 2, A plasma processing apparatus comprising a heat-conducting member positioned between the second bracket and the outer peripheral wall surface of the processing gas supply line and in contact with both.

4. A plasma processing apparatus according to claim 3, A plasma processing apparatus comprising an elastic member having heat transfer properties, which is in contact with the second bracket and the outer peripheral wall surface of the processing gas supply line.

5. A plasma processing apparatus according to claim 1, A plasma processing apparatus comprising, in the case where the vaporization unit has the first bracket, a heat-transferring member disposed between the first bracket and the outer peripheral wall surface of the liquid raw material supply line and in contact with both.

6. A plasma processing apparatus according to claim 5, A plasma processing apparatus comprising an elastic member having heat transfer properties, which is in contact with the first bracket and the outer peripheral wall surface of the liquid raw material supply line.

7. A plasma processing apparatus according to claim 1, The vaporization unit section has a third bracket with heat transfer properties to which the vaporizer and the flow rate controller are attached. The vaporizer includes a first heater, The flow rate controller is a plasma processing apparatus that includes a second heater.

8. A plasma processing apparatus according to claim 7, The first bracket is, It is attached in contact with the surface of the vaporizer, or attached in contact with the surface of a heat-conducting member that is in contact with the surface of the vaporizer. The second bracket is, A plasma processing apparatus that is mounted in contact with the surface of the flow controller, or in contact with the surface of a heat-conducting member that is in contact with the surface of the flow controller.

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