Ozone supply system, substrate processing apparatus, and ozone supply method

Abstract

To provide a technique for stabilizing generation of ozone in an ozone generator.SOLUTION: An ozone supply system includes a supply path configured to supply a gas, and an ozone generator, provided in the supply path, and configured to generate ozone using oxygen gas supplied from an upstream side of the supply path, and supply an ozone-containing gas containing the ozone to a downstream side. The supply path branches into a plurality of branching paths on the downstream side from the ozone generator. At least one branching path of the plurality of branching paths is a process branching path connected to a processing part that uses the ozone-containing gas, and a remaining branching path, other than the at least one branching path, of the plurality of branching paths is a waste branching path connected to a waste part configured to discharge the ozone-containing gas. The waste branching path includes a waste flow controller configured to control a flow rate of the ozone-containing gas.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an ozone supply system, a substrate processing apparatus, and an ozone supply method.

Background Art

[0002] When performing oxidation or etching of a substrate in a processing chamber, a substrate processing apparatus may use ozone (O3) as a processing gas. In this case, an ozone supply system is connected to the processing chamber. The ozone supply system includes an ozone generator that generates ozone by discharging oxygen (O2).

[0003] In recent years, an ozone supply system that supplies ozone from one ozone generator to a plurality of processing chambers has been developed in order to reduce manufacturing costs and footprint. For example, Patent Document 1 discloses a technique for stabilizing the supply of ozone by changing the discharge output of an ozone generator according to fluctuations in the flow rate of a raw material gas when supplying from one ozone generator to a plurality of processing chambers.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present disclosure provides a technique capable of stabilizing the generation of ozone in an ozone generator.

Means for Solving the Problems

[0006] According to one aspect of the present disclosure, the present invention comprises a supply path for supplying gas, and an ozone generator provided in the supply path for generating ozone using oxygen gas supplied from the upstream side of the supply path and sending the ozone-containing gas to the downstream side, wherein the supply path branches into a plurality of branch paths downstream of the ozone generator, at least one of the plurality of branch paths is a processing branch path connected to a processing unit that uses the ozone-containing gas, the processing branch path includes a processing flow rate adjustment unit for adjusting the flow rate of the ozone-containing gas supplied to the processing unit, the remaining of the plurality of branch paths are waste branch paths connected to a waste unit that discharges the ozone-containing gas, the waste branch path includes a waste flow rate adjustment unit for adjusting the flow rate of the ozone-containing gas. The supply path upstream of the ozone generator includes an upstream flow rate adjustment unit for adjusting the flow rate of the oxygen gas, and when no errors occur in the upstream flow rate adjustment unit and the processing flow rate adjustment unit, the flow rate of the ozone-containing gas in the waste flow rate adjustment unit is set to a value greater than the sum of the error in the oxygen gas flow rate of the upstream flow rate adjustment unit and the error in the flow rate of the ozone-containing gas in the processing flow rate adjustment unit. An ozone supply system is provided, which includes a pressure sensor provided in the supply path between the ozone generator and the branching point of the plurality of branch paths, for approximately detecting the pressure of the ozone generator, and a control unit that adjusts the flow rate of the ozone-containing gas by the waste flow rate adjustment unit without changing the flow rate of the ozone-containing gas by the processing flow rate adjustment unit when the pressure value detected by the pressure sensor changes when the ozone-containing gas is supplied to the processing unit. [Effects of the Invention]

[0007] According to one embodiment, the generation of ozone in an ozone generator can be stabilized. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram illustrating an ozone supply system according to one embodiment. [Figure 2] This is a schematic cross-sectional view showing a substrate processing apparatus equipped with an ozone supply system. [Figure 3] This is a block diagram showing the functional block of the control unit for the ozone supply system. [Figure 4]Figure 4(A) is an explanatory diagram showing the operation of the ozone supply system according to this embodiment. Figure 4(B) is an explanatory diagram showing the operation of an ozone supply system according to a reference example. [Figure 5] This flowchart shows the method of supplying ozone in an ozone supply system. [Figure 6] This is a schematic diagram illustrating a modified ozone supply system. [Modes for carrying out the invention]

[0009] The following describes embodiments for implementing this disclosure with reference to the drawings. In each drawing, the same reference numerals are used for identical components, and redundant explanations may be omitted.

[0010] [Configuration of the ozone supply system] As shown in Figure 1, the ozone supply system 100 according to one embodiment is installed in the substrate processing apparatus 1 and supplies ozone-containing gas containing ozone (O3) to the processing container 10 to be supplied. Furthermore, the ozone supply system 100 according to this embodiment is configured to supply ozone-containing gas to multiple (two in Figure 1) processing containers 10 of the substrate processing apparatus 1. In the following description, the two processing containers 10 of the substrate processing apparatus 1 will also be referred to as the first processing container 10A and the second processing container 10B.

[0011] The ozone supply system 100 has a supply path 110 for supplying ozone-containing gas to each processing container 10. The supply path 110 is formed by connecting multiple pipes that are coated with, for example, a corrosion-resistant coating. The supply path 110 branches out to supply ozone-containing gas to the first processing container 10A and the second processing container 10B, respectively. Specifically, the supply path 110 comprises one common path 111 and branch paths 112 (first processing branch path 113, second processing branch path 114, and waste branch path 115) that branch off at the downstream end (branching point S) of this common path 111.

[0012] The first processing branch route 113 is connected to the first processing container 10A and supplies ozone-containing gas to the first processing container 10A. The second processing branch route 114 is connected to the second processing container 10B and supplies ozone-containing gas to the second processing container 10B. The waste branch route 115 is connected to the waste section 200 for treating exhaust gas and disposes of the ozone-containing gas. In this way, the ozone supply system 100 has one more branch route 112 than the number of processing containers 10 to which the ozone-containing gas is supplied, thereby achieving stability when supplying ozone-containing gas.

[0013] Specifically, the ozone supply system 100 comprises, in order from upstream to downstream of the common path 111, an oxygen supply source 120, an upstream flow regulator 121, an ozone generator 122, a pressure sensor 123, a flow control valve 124, and a shut-off valve 125. The supply path 110 branches into three branch paths 112 at branching point S downstream of the shut-off valve 125 of the common path 111. The ozone supply system 100 also has a control unit 160 that controls the configuration of the system.

[0014] The oxygen source 120 of the ozone supply system 100 supplies oxygen (O2) gas to the common path 111 downstream. The oxygen source 120 is not particularly limited and may be a high-pressure tank capable of storing oxygen gas, or a compressor, pump, etc. that takes in air and pumps it. The ozone generator 122 downstream of the oxygen source 120 can increase the ozone concentration by increasing the dissociation efficiency of oxygen molecules when supplied with oxygen gas containing nitrogen gas.

[0015] The upstream flow regulator 121 can be, for example, a mass flow controller (MFC) (hereinafter referred to as the upstream MFC 121). The upstream MFC 121 adjusts the flow rate of oxygen gas supplied to the ozone generator 122 based on a target flow rate command from the control unit 160. The ozone supply system 100 can control the pressure applied to the ozone generator 122 from the primary side by adjusting the flow rate of oxygen gas with the upstream MFC 121.

[0016] The ozone generator 122 is a discharge-type device that generates ozone by discharging the oxygen gas supplied from the upstream side. For example, the ozone generator 122 forms a discharge region between a pair of electrodes arranged in a parallel plate shape or a coaxial cylindrical shape. Then, the ozone generator 122 generates a discharge in the oxygen gas by applying an alternating high voltage between the pair of electrodes while flowing the oxygen gas through the discharge region, thereby generating ozone. By continuously applying a voltage while flowing the oxygen gas, the ozone generator 122 can continuously generate ozone with a substantially constant concentration. And the ozone generator 122 sends the generated ozone-containing gas to the common path 111 on the secondary side (downstream side).

[0017] The pressure sensor 123 is provided on the downstream side of the ozone generator 122 in the common path 111 and detects the pressure of the ozone-containing gas flowing through the common path 111. This pressure sensor 123 is connected to the control unit 160 and transmits the detected pressure value to the control unit 160. The pressure sensor 123 provided near the downstream side of the ozone generator 122 can approximately detect the pressure inside the ozone generator 122.

[0018] The flow rate adjustment valve 124 opens and closes the flow path in the common path 111 and adjusts the opening degree under the control of the control unit 160 to adjust the amount of the ozone-containing gas flowing out from the ozone generator 122 to the secondary side. Also, the shut-off valve 125 blocks the flow path of the common path 111 when the pressure inside the ozone generator 122 drops below a predetermined value or in an emergency such as a trouble occurrence, thereby shutting off the supply of the ozone-containing gas.

[0019] And the first processing branch path 113 of the branch path 112 includes a first processing MFC 130 which is a first flow rate adjustment unit and a first on-off valve 131. Similarly, the second processing branch path 114 of the branch path 112 includes a second processing MFC 140 which is a second flow rate adjustment unit and a second on-off valve 141. Also, the waste branch path 115 of the branch path 112 includes a waste MFC 150 which is a waste flow rate adjustment unit and a third on-off valve 151.

[0020] The MFC 130 for the first treatment, the MFC 140 for the second treatment, and the MFC 150 for disposal adjust the flow rate of the ozone-containing gas in their respective branch paths 112 based on the command of the target flow rate from the control unit 160. That is, the MFC 130 for the first treatment supplies the ozone-containing gas of the required supply amount to the first treatment container 10A by maintaining the flow rate of the ozone-containing gas at the target flow rate. The MFC 140 for the second treatment supplies the ozone-containing gas of the required supply amount to the second treatment container 10B by maintaining the flow rate of the ozone-containing gas at the target flow rate. For example, in the ozone supply system 100, it is preferable to set the target flow rate of the MFC 130 for the first treatment and the target flow rate of the MFC 140 for the second treatment to the same value during the treatment of the first treatment container 10A and the second treatment container 10B. Thereby, the ozone supply system 100 can evenly disperse the ozone-containing gas in each of the first treatment branch path 113 and the second treatment branch path 114.

[0021] The MFC 150 for disposal adjusts the flow rate of the ozone-containing gas discharged to the disposal unit 200 based on the disposal flow rate (target flow rate) commanded by the control unit 160. The control unit 160 of the ozone supply system 100 according to the present embodiment adjusts the flow rate of the ozone-containing gas discharged to the disposal unit 200 based on the pressure value of the pressure sensor 123. This control will be described in detail later.

[0022] Also, the first on-off valve 131, the second on-off valve 141, and the third on-off valve 151 switch the supply and supply cut-off of the ozone-containing gas by opening and closing the flow paths of the respective branch paths 112. For example, when starting the supply of the ozone-containing gas to each treatment container 10, the ozone supply system 100 simultaneously opens the first on-off valve 131, the second on-off valve 141, and the third on-off valve 151 to allow the ozone-containing gas to flow. Note that the opening and closing timings of the respective valves may be different from each other. As an example, when starting the supply of the ozone-containing gas, the third on-off valve 151 may be opened first, and then the first on-off valve 131 and the second on-off valve 141 may be opened.

[0023] The control unit 160 controls the upstream MFC 121, ozone generator 122, first processing MFC 130, second processing MFC 140, waste MFC 150, first to third on / off valves 131, 141, 151, etc., to supply ozone-containing gas. The control unit 160 is a control computer having one or more processors 161, memory 162, input / output interfaces (not shown), and electronic circuits. The one or more processors 161 are a combination of one or more CPUs, GPUs, ASICs, FPGAs, or circuits consisting of multiple discrete semiconductors. The memory 162 includes non-volatile memory and volatile memory and forms the storage unit of the control unit 160.

[0024] [Configuration of the substrate processing device 1] Next, an example of a substrate processing apparatus 1 equipped with the above-described ozone supply system 100 will be explained. As shown in Figure 2, an example of a substrate processing apparatus 1 that uses ozone-containing gas is a film deposition apparatus that forms an oxide film on the surface of a substrate W by atomic layer deposition (ALD). Furthermore, the substrate processing apparatus 1 according to this embodiment has two processing containers 10 (first processing container 10A, second processing container 10B), making it a so-called two-wafer film deposition apparatus that can process two substrates W simultaneously or in parallel.

[0025] Examples of substrates W to which the film deposition process is performed include semiconductor substrates such as silicon wafers or compound semiconductor wafers. Examples of oxide films include high-k films such as HfO2 films, ZrO2 films, La2O3 films, and Y2O3 films. In this embodiment, an apparatus for depositing an HfO2 film on a silicon wafer will be used as an example.

[0026] Specifically, the substrate processing apparatus 1 includes a susceptor 20, a shower head 30, an exhaust unit 40, and a gas supply unit 50, which are installed or connected to each processing container 10. Furthermore, the substrate processing apparatus 1 has a control device 90 that controls each of these components to perform the film deposition process.

[0027] Each processing container 10 is made of a metal such as aluminum and has a processing space 10s inside for performing film deposition on a substrate W. Each processing container 10 is formed in a substantially cylindrical shape according to the planar shape of the substrate W to be contained. Each processing container 10 also includes an inlet / outlet 11 for loading and unloading the substrate W, and a gate valve 12 for opening and closing the inlet / outlet 11.

[0028] Furthermore, the processing container 10 is equipped with an annular discharge duct 13 at its top. The discharge duct 13 has a slit 13a that communicates with the processing space 10s along the circumferential direction of its inner surface, and an outlet 13b at a predetermined position on its outer surface.

[0029] The susceptor 20 is made of nickel or the like and is supported by a support member 23 within each processing container 10. The susceptor 20 is formed in a planar shape (perfectly circular) corresponding to the substrate W and supports the substrate W horizontally. The susceptor 20 also has a heater 21 inside for heating the substrate W placed on its mounting surface (upper surface). The mounting surface of the susceptor 20 is temperature-controlled by the heater 21 to, for example, 300 to 450°C. The susceptor 20 is also equipped with a cover member 22 made of ceramics such as alumina so as to cover the outer peripheral region of the mounting surface of the substrate W and the sides of the susceptor 20.

[0030] A support member 23 supporting the susceptor 20 extends from the center of the bottom surface of the susceptor 20, through a hole formed in the bottom wall of the processing container 10, and downwards from the processing container 10, with its lower end connected to a vertical movement mechanism 24. The susceptor 20 moves up and down via the support member 23 and the vertical movement mechanism 24. Specifically, the vertical movement mechanism 24 displaces the susceptor 20 between a processing position for film deposition on the substrate W and a transport position below the processing position that allows for transport of the substrate W. Also, a bellows 25 that expands and contracts in conjunction with the vertical movement of the susceptor 20, and a flange portion 26 that closes the lower end of the bellows 25 are provided vertically below the processing container 10.

[0031] Each processing container 10 is equipped with a substrate lifting section 27 on its bottom wall. The substrate lifting section 27 includes a lifting plate 27a, a plurality (for example, three) of support pins 27b protruding upward from the lifting plate 27a, and a pin vertical movement mechanism 27c for raising and lowering the lifting plate 27a. When a substrate W is loaded into the processing container 10, the substrate lifting section 27 receives the substrate W, which has been transported by a substrate transport mechanism (not shown), by raising each support pin 27b, and then places the substrate W on the susceptor 20 at the processing position by lowering each support pin 27b. Conversely, when a substrate W is unloaded from the processing container 10, the substrate lifting section 27 levitates the substrate W from the susceptor 20 at the processing position by raising each support pin 27b, and hands the substrate W over to the entering substrate transport mechanism.

[0032] The shower head 30 is made of, for example, aluminum and is positioned vertically above each processing container 10, facing the susceptor 20. The shower head 30 has a main body 31 and a shower plate 32.

[0033] The main body 31 is formed in a substantially cylindrical shape and has a recess 34 in the center of its lower vertical side that serves as a gas diffusion space 33. A flange 31a is provided on the upper side of the outer edge of the main body 31, projecting radially outward and engaging with the discharge duct 13. The space between the flange 31a and the discharge duct 13 is airtightly sealed by a sealing material 15. The main body 31 also includes a gas introduction section 35 projecting vertically upward from its upper center. The gas introduction section 35 has a lower gas passage 35a connected to the gas diffusion space 33, and two upper gas passages 35b and 35c connected to the lower gas passage 35a.

[0034] The shower plate 32 is mounted on the vertically lower side of the main body 31 so as to cover the recess 34. The recess 34 and the shower plate 32 define a gas diffusion space 33. The shower plate 32 has a plurality of gas discharge holes 32a that discharge gas from the gas diffusion space 33.

[0035] The exhaust section 40 includes an exhaust path 41 connected to the outlet 13b of the exhaust duct 13 of each processing container 10. The exhaust path 41 branches into two upstream to discharge the gas from the first processing container 10A and the second processing container 10B. Each branch of the exhaust path 41 is provided with a pressure control valve (APC) 42 for adjusting the pressure inside each processing container 10. A vacuum pump 43 and a waste section 200 for processing the exhaust gas are provided at the confluence of the exhaust paths 41. During the film deposition process, the substrate processing apparatus 1 operates the vacuum pump 43 to suck out the gas from each processing container 10. As a result, the gas from each processing container 10 is discharged from the exhaust duct 13 through the exhaust path 41 to the waste section 200.

[0036] The gas supply unit 50 includes a raw material gas supply system 51 for supplying raw material gas and the ozone supply system 100 described above.

[0037] The raw material gas supply system 51 includes a raw material gas supply path 52 connected to the upper gas flow path 35b. The raw material gas supply system 51 also branches the raw material gas supply path 52 in order to supply raw material gas to the first processing container 10A and the second processing container 10B. In other words, the raw material gas supply path 52 has a common path 53, a first processing branch path 54 extending from the common path 53 to the first processing container 10A, and a second processing branch path 55 extending from the common path 53 to the second processing container 10B.

[0038] The raw material gas supply system 51 is equipped with a raw material gas source 56 upstream of the common path 111. The raw material gas supplied by the raw material gas source 56 is not particularly limited as long as it can form a metal-containing film in the film formation process, and may be an organic compound or an inorganic compound. For example, when forming an HfO2 film, organic hafnium compounds such as tetrakisdimethylaminohafnium (Hf[N(CH3)2]4:TDMAH) or tri(dimethylamino)cyclopentadienylhafnium, or hafnium chloride (HfCl4), can be used.

[0039] Furthermore, the first processing branch route 54 and the second processing branch route 55 are each provided with flow controllers 57A and 57B, such as mass flow controllers, and on / off valves 58A and 58B, in order from upstream to downstream. The substrate processing apparatus 1 controls the flow controller 57A and on / off valve 58A of the first processing branch route 54 using the control device 90 to switch the flow of raw material gas on and off, and adjust the flow rate of raw material gas supplied to the first processing container 10A. Similarly, the substrate processing apparatus 1 controls the flow controller 57B and on / off valve 58B of the second processing branch route 55 using the control device 90 to switch the flow of raw material gas on and off, and adjust the flow rate of raw material gas supplied to the second processing container 10B. The gas supply unit 50 may also connect a purge gas route (not shown) for supplying purge gas such as nitrogen (N2) gas to the raw material gas supply route 52. The purge gas can be used as a counterflow during the film deposition process.

[0040] As described above, the ozone supply system 100 includes a first processing branch path 113, a second processing branch path 114, and a waste branch path 115. The ozone supply system 100 supplies ozone-containing gas to the first processing container 10A via the first processing branch path 113, and also supplies ozone-containing gas to the second processing container 10B via the second processing branch path 114. Furthermore, the waste branch path 115 of the ozone supply system 100 is connected to the discharge path 41 of the substrate processing apparatus 1 (upstream of the vacuum pump 43). As a result, the substrate processing apparatus 1 can directly discharge ozone-containing gas to a common waste section 200 without going through each processing container 10 by circulating the ozone-containing gas through the waste branch path 115.

[0041] The control device 90 controls the susceptor 20, exhaust unit 40, raw material gas supply system 51, etc., to perform film deposition processing in the processing container 10. The control device 90 is a control computer having one or more processors, memory, input / output interfaces, and electronic circuits (not shown). The one or more processors are a combination of one or more CPUs, GPUs, ASICs, FPGAs, or circuits consisting of multiple discrete semiconductors. The memory includes non-volatile memory and volatile memory and forms the storage unit of the control device 90. The memory stores programs for controlling the film deposition process and recipes to be executed in the film deposition process. The processor reads the programs and recipes stored in the memory and performs control.

[0042] Furthermore, the control device 90 outputs a supply command, a supply termination command, etc., to the control unit 160 of the ozone supply system 100 at an appropriate timing during the film formation process in order to supply ozone-containing gas to the first processing container 10A and the second processing container 10B. The supply command includes, for example, a target flow rate of ozone-containing gas in addition to the command information for starting the supply. As a result, the control unit 160 controls each component to supply ozone-containing gas to the first processing container 10A and the second processing container 10B according to the target flow rate. In this embodiment, the control unit 160 of the ozone supply system 100 and the control device 90 of the substrate processing apparatus 1 are provided separately, but the invention is not limited to this, and the control device 90 may also have the functions of the control unit 160 (functions for controlling the supply of ozone-containing gas).

[0043] [Control unit 160 of ozone supply system 100] The control unit 160 of the ozone supply system 100 constructs a functional block for supplying ozone-containing gas, as shown in Figure 3, by having the processor 161 read and execute a program stored in the memory 162. Specifically, the control unit 160 contains a pressure acquisition unit 170, an ozone generation control unit 171, a processing-side supply control unit 172, and a waste-side control unit 173.

[0044] The pressure acquisition unit 170 continuously acquires the pressure value from the pressure sensor 123 installed in the supply path 110, temporarily stores it in the memory 162, and outputs the pressure value to the ozone generation control unit 171 and the waste side control unit 173, etc.

[0045] The ozone generation control unit 171 controls the upstream MFC 121, the ozone generator 122, the flow rate adjustment valve 124, etc., to supply oxygen gas to the ozone generator 122 and generate ozone-containing gas within the ozone generator 122. In addition, during the generation of ozone-containing gas, the ozone generation control unit 171 controls the upstream MFC 121 and the flow rate adjustment valve 124 based on the pressure value of the pressure sensor 123 to stabilize the concentration of ozone-containing gas generated in the ozone generator 122.

[0046] The processing-side supply control unit 172 controls the first processing MFC 130, the second processing MFC 140, the first on / off valve 131, and the second on / off valve 141 based on the target flow rate obtained from the control device 90. This allows the processing-side supply control unit 172 to adjust the supply and cessation of ozone-containing gas to each processing container 10, as well as the amount (flow rate) supplied. In this embodiment, the processing-side supply control unit 172 simultaneously supplies ozone-containing gas to the first processing container 10A and the second processing container 10B, and also supplies the same amount of ozone residue. However, the ozone supply system 100 may supply ozone-containing gas to the first processing container 10A and to the second processing container 10B at different timings. For example, the ozone supply system 100 may supply ozone-containing gas to the first processing container 10A while the supply of ozone-containing gas to the second processing container 10B is stopped.

[0047] The waste-side control unit 173 controls the flow rate of ozone-containing gas circulating through the waste branch path 115. Inside this waste-side control unit 173, a waste flow rate calculation unit 174 and a waste branch path control unit 175 are formed. The waste flow rate calculation unit 174 calculates the flow rate of ozone-containing gas to control the waste MFC 150 based on the pressure value from the pressure sensor 123 acquired by the pressure acquisition unit 170. For example, the waste flow rate calculation unit 174 stores map information MI or a function that associates pressure values ​​with the flow rate of ozone-containing gas in memory 162 in advance. When it receives a pressure value, it refers to the map information MI in memory 162 and extracts the flow rate corresponding to the pressure value.

[0048] The waste branch route control unit 175 controls the waste MFC 150 and the third on / off valve 151 based on the flow rate of ozone-containing gas calculated by the waste flow rate calculation unit 174, thereby controlling the discharge and cessation of discharge of ozone-containing gas to the waste section 200, as well as the waste flow rate. In other words, when the ozone supply system 100 supplies ozone-containing gas to the first processing container 10A and the second processing container 10B, it adjusts the flow rate of ozone-containing gas to be discharged to the waste section 200. The significance of controlling the flow rate of ozone-containing gas in the waste branch route 115 will be explained below.

[0049] As shown in Figures 4(A) and (B), the upstream MFC 121 of the common path 111, the first processing MFC 130 of the first processing branch path 113, and the second processing MFC 140 of the second processing branch path 114 each adjust the flow rate of the gas flowing through them. However, each MFC generally experiences a flow rate error of about ±1% from the target value. For example, in the ozone supply system 100' reference example without the waste branch path 115 shown in Figure 4(B), suppose a -1% error occurs in the upstream MFC 121, and a +1% error occurs in each of the first processing MFC 130 and the second processing MFC 140. In this case, in the ozone generator 122, the flow rate of oxygen gas flowing into the ozone generator 122 is low, while the flow rate of ozone-containing gas discharged from the ozone generator 122 is high. As a result, the pressure inside the ozone generator 122 decreases.

[0050] If the pressure drop in the ozone generator 122 becomes large due to errors, the ozone supply system 100' controls the supply of oxygen gas and the discharge of ozone-containing gas by changing the amount of oxygen gas supplied or the amount of ozone-containing gas discharged using the upstream MFC 121 or the flow control valve 124. This causes the ozone concentration to become unstable. In particular, when supplying ozone-containing gas to multiple processing containers 10, the error can be several times greater than when supplying ozone-containing gas to a single processing container 10, making it easier for pressure fluctuations in the ozone generator 122 to become larger. In some cases, the system may be shut down if it is determined that there is an abnormality in the generation of ozone-containing gas.

[0051] As shown in Figure 4(A), the ozone supply system 100 according to this embodiment includes a waste branch path 115 in the supply path 110. That is, the ozone supply system 100 discharges a portion of the ozone-containing gas via the waste branch path 115 by circulating the supernatant of the ozone-containing gas from the ozone generator 122 through the waste branch path 115. This allows pressure fluctuations caused by flow rate changes in other paths to be compensated for by changes in the flow rate of the waste branch path 115.

[0052] Specifically, the control unit 160 adjusts the flow rate of the ozone-containing gas in the waste MFC 150 to absorb the errors in the upstream MFC 121, the first processing MFC 130, and the second processing MFC 140. As a result, the ozone supply system 100 can control the pressure value of the pressure sensor 123 to remain constant at the target pressure without requiring adjustments by the upstream MFC 121 or the flow rate adjustment valve 124.

[0053] The waste flow rate of the waste MFC 150 may be set lower than the flow rates of the first treatment MFC 130 and the second treatment MFC 140, or it may be set to be the same as the flow rates of the first treatment MFC 130 and the second treatment MFC 140. A lower waste flow rate reduces the amount of ozone-containing gas that does not flow through the treatment container 10. However, the waste flow rate is set to a value greater than the total amount of errors of the upstream MFC 121, the first treatment MFC 130, and the second treatment MFC 140. For example, if the error of the upstream MFC 121 is ±30 ccm, the error of the first treatment MFC 130 is ±10 ccm, and the error of the second treatment MFC 140 is ±10 ccm, the waste flow rate of the waste MFC 150 should be set to a value greater than 50 ccm.

[0054] For example, if the oxygen gas flow rate decreases in the upstream MFC 121 and the ozone-containing gas flow rate increases in the first treatment MFC 130 and the second treatment MFC 140, the pressure inside the ozone generator 122 will fall below the target pressure. Therefore, the control unit 160 controls the waste MFC 150 based on the pressure value of the pressure sensor 123 to reduce the amount of ozone-containing gas flowing through the waste branch path 115. As a result, the flow rate of ozone-containing gas flowing through the waste branch path 115 decreases, and the pressure inside the ozone generator 122 rises. In other words, the ozone supply system 100 can return the pressure inside the ozone generator 122 to the target pressure without adjusting the flow rates of the first treatment branch path 113 and the second treatment branch path 114.

[0055] Conversely, if the oxygen gas flow rate increases in the upstream MFC 121 and the ozone-containing gas flow rate decreases in the first treatment MFC 130 and the second treatment MFC 140, the pressure inside the ozone generator 122 will rise above the target pressure. Therefore, the control unit 160 controls the waste MFC 150 based on the pressure value of the pressure sensor 123 to increase the amount of ozone-containing gas flowing through the waste branch path 115. This increases the flow rate of ozone-containing gas flowing through the waste branch path 115, and the pressure on the ozone generator 122 side decreases. In other words, the ozone supply system 100 can return the pressure inside the ozone generator 122 to the target pressure without adjusting the flow rates of the first treatment branch path 113 and the second treatment branch path 114.

[0056] [Ozone supply method] The ozone supply system 100 and substrate processing apparatus 1 according to this embodiment are basically configured as described above, and the operation of the ozone supply system 100 (ozone supply method) will be described below.

[0057] The control unit 160 of the ozone supply system 100 receives a supply command from the control unit 90 when the substrate processing apparatus 1 is performing substrate processing (step S1). As a result, the control unit 160 starts generating ozone-containing gas. First, the ozone generation control unit 171 controls the upstream MFC 121, the ozone generator 122, the flow rate adjustment valve 124, etc. to supply oxygen gas to the ozone generator 122 and generate ozone by performing a discharge inside the ozone generator 122 (step S2).

[0058] Then, the processing-side supply control unit 172 starts supplying ozone-containing gas to each processing container 10 (step S3). Specifically, the processing-side supply control unit 172 operates the first processing MFC 130 and the second processing MFC 140 so that the flow rate is the target flow rate included in the supply command. As a result, the ozone-containing gas generated by the ozone generator 122 is supplied to the first processing container 10A via the first processing branch path 113 and to the second processing container 10B via the second processing branch path 114.

[0059] Furthermore, as ozone-containing gas is supplied to each processing container 10, the waste-side control unit 173 starts the flow of ozone-containing gas from the waste branch path 115 to the waste section 200 (step S4). Specifically, the waste-side control unit 173 opens the third on / off valve 151 and operates the waste MFC 150, thereby allowing ozone-containing gas to flow through the waste branch path 115.

[0060] When ozone-containing gas is supplied to the secondary side, the pressure acquisition unit 170 of the control unit 160 detects the pressure value of the ozone-containing gas supplied from the ozone generator 122 using the pressure sensor 123 and continuously acquires this pressure value (step S5).

[0061] Furthermore, after the supply of ozone-containing gas is started, the processing-side supply control unit 172 adjusts the flow rate of the first processing MFC 130 and the flow rate of the second processing MFC 140 to the same amount and continuously supplies ozone-containing gas to the first processing container 10A and the second processing container 10B (step S6).

[0062] Meanwhile, the waste-side control unit 173, while supplying ozone-containing gas to each processing container 10, controls the waste MFC 150 to adjust the flow rate of the waste branch path 115 based on the pressure value of the pressure sensor 123 acquired by the pressure acquisition unit 170 (step S7). Specifically, the waste flow rate calculation unit 174 calculates the flow rate of ozone-containing gas in the waste branch path 115 based on the pressure value of the pressure sensor 123. The waste branch path control unit 175 also sends a flow rate adjustment command to the waste MFC 150 according to the waste flow rate calculated by the waste flow rate calculation unit 174. As a result, the waste MFC 150 adjusts the flow rate of ozone-containing gas discharged from the waste branch path 115 to the waste unit 200.

[0063] Then, the control unit 160 determines whether or not to terminate the supply of ozone-containing gas based on the supply stop command from the control device 90 and a predetermined processing period (step S8). If the supply of ozone-containing gas is to be continued (step S8: NO), the process returns to step S6 and the same process is repeated. On the other hand, if it is determined that the supply of ozone-containing gas should be terminated (step S8: YES), the control unit 160 performs termination processing to stop the supply of ozone-containing gas. For example, in termination processing, the control unit 160 stops the supply of oxygen gas, stops the ozone generator 122, shuts off each branch path 112, etc.

[0064] As described above, the ozone supply system 100 can maintain a constant pressure inside the ozone generator 122 by discharging ozone-containing gas to the waste branch path 115 connected to the waste section 200. This enables the ozone supply system 100 to stably generate ozone-containing gas of a constant concentration inside the ozone generator 122, and to efficiently supply the generated ozone-containing gas to each processing container 10.

[0065] As another example, even if the ozone supply system 100 stops supplying ozone-containing gas to the second processing container 10B, it can divert the ozone-containing gas that would otherwise flow to the second processing container 10B to the waste branch route 115. Therefore, the flow rate of ozone-containing gas to the first processing container 10A does not need to be changed. Thus, even in the event of a malfunction, for example, the substrate processing device 1 can avoid wasting substrates W being processed in both the first processing container 10A and the second processing container 10B.

[0066] Furthermore, the ozone supply system 100 is not limited to the above configuration and can take various modifications. For example, the number of targets to which the ozone-containing gas is supplied by the ozone supply system 100 is not limited to two, but may be three or more.

[0067] Conversely, the ozone supply system 100 is not limited to supplying ozone-containing gas to multiple processing containers 10, but may also be configured to supply ozone-containing gas to a single processing container 10. In this case as well, the ozone supply system 100 may have two branch paths 112, with one branch path 112 connected to one processing container 10 and the other branch path 112 connected to a waste unit 200. Alternatively, the ozone supply system 100 may have three or more branch paths 112, with one branch path 112 connected to a waste unit 200 and the other multiple branch paths 112 connected to a single processing container 10.

[0068] For example, as shown in Figure 6, the ozone supply system 100 may also include a waste flow rate adjustment valve 152 that can adjust the opening of the flow path in the waste branch path 115, instead of a waste MFC 150 (mass flow controller) as a waste flow rate adjustment unit. The waste flow rate adjustment valve 152 can easily adjust the flow rate of the ozone-containing gas flowing through the waste branch path 115. In short, the ozone supply system 100 may employ various configurations that can adjust the flow rate of the ozone-containing gas flowing through the waste branch path 115 as a waste flow rate adjustment unit.

[0069] The technical ideas and effects of this disclosure, as described in the embodiments above, are described below.

[0070] An ozone supply system 100 according to a first aspect of the present disclosure includes a supply path 110 for supplying gas, and an ozone generator 122 provided in the supply path 110 for generating ozone using oxygen gas supplied from the upstream side of the supply path 110 and sending the ozone-containing gas containing the ozone to the downstream side. The supply path 110 branches into a plurality of branch paths 112 downstream of the ozone generator 122, and at least one of the plurality of branch paths 112 is a processing branch path (first processing branch path 113, second processing branch path 114) connected to a processing unit (processing container 10) that uses the ozone-containing gas, and the remaining of the plurality of branch paths 112 are waste branch paths 115 connected to a waste unit 200 that discharges the ozone-containing gas, and the waste branch path 115 includes a waste flow rate adjustment unit (waste MFC 150, waste flow rate adjustment valve 152) for adjusting the flow rate of the ozone-containing gas.

[0071] As described above, the ozone supply system 100 directs a portion of the ozone-containing gas sent from the ozone generator 122 to the waste branch path 115, so that fluctuations in the pressure of the ozone generator 122 and the supply path 110 can be compensated for by changes in the flow rate of the waste branch path 115. In other words, the ozone supply system 100 can stabilize the pressure in the ozone generator 122 upstream of the multiple branch paths 112 by adjusting the flow rate of the ozone-containing gas in the waste branch path 115 using the waste MFC 150 and the waste flow rate adjustment valve 152. As a result, the ozone generator 122 can stably generate ozone.

[0072] Furthermore, the ozone supply system 100 is equipped with a pressure sensor 123 in the supply path 110 between the ozone generator 122 and the branching point S of the multiple branch paths 112, and has a control unit 160 that controls the flow rate of ozone-containing gas by a waste flow rate adjustment unit (waste MFC 150, waste flow rate adjustment valve 152) based on the pressure value detected by the pressure sensor 123. As a result, the ozone supply system 100 can discharge ozone-containing gas at an appropriate flow rate from the waste branch path 115 based on the pressure value of the pressure sensor 123.

[0073] Furthermore, the control unit 160 controls the waste flow rate adjustment unit (waste MFC 150, waste flow rate adjustment valve 152) so that the pressure value of the pressure sensor 123 remains constant at the target pressure. As a result, the ozone supply system 100 can maintain a constant pressure inside the ozone generator 122, thereby stabilizing the concentration of the generated ozone.

[0074] Furthermore, the control unit 160 controls the waste flow rate adjustment unit (waste MFC 150, waste flow rate adjustment valve 152) to reduce the flow rate of ozone-containing gas when the pressure value is lower than the target pressure, and controls the waste flow rate adjustment unit to increase the flow rate of ozone-containing gas when the pressure value is higher than the target pressure. As a result, the ozone supply system 100 can easily and accurately maintain a constant pressure inside the ozone generator 122.

[0075] Furthermore, the supply path 110 includes multiple processing branch paths (first processing branch path 113, second processing branch path 114) connected to multiple processing units (first processing container 10A, second processing container 10B), and processing flow rate adjustment units (first processing MFC 130, second processing MFC 140) provided in each of the multiple processing branch paths to adjust the flow rate of ozone-containing gas supplied to the multiple processing units. By supplying ozone-containing gas to multiple processing units in this way, the ozone supply system 100 can promote reductions in manufacturing costs and footprint. In addition, even with this configuration, the generation of ozone-containing gas in the ozone generator 122 can be stabilized by the waste branch path 115 and the waste flow rate adjustment unit.

[0076] Furthermore, the multiple processing flow rate adjustment units (first processing MFC 130, second processing MFC 140) adjust the flow rate of the ozone-containing gas to be the same for all of them. As a result, the ozone supply system 100 can stably perform the same processing using the ozone-containing gas supplied to each of the multiple processing units (first processing container 10A, second processing container 10B).

[0077] Furthermore, the waste flow rate adjustment unit is a mass flow controller (waste MFC150). This allows the ozone supply system 100 to accurately adjust the flow rate of ozone-containing gas circulating through the waste branch path 115.

[0078] Furthermore, the waste flow rate adjustment unit is a flow rate adjustment valve (waste flow rate adjustment valve 152) that adjusts the opening of the flow path of the waste branch route 115. Even in this case, the ozone supply system 100 can easily adjust the flow rate of the ozone-containing gas flowing through the waste branch route 115.

[0079] Furthermore, a second aspect of the present disclosure is a substrate processing apparatus 1 comprising a processing container 10 for processing a substrate W, and an ozone supply system 100 for supplying an ozone-containing gas containing ozone into the processing container 10, wherein the ozone supply system 100 includes a supply path 110 for supplying gas, and an ozone generator 122 provided in the supply path 110, which generates ozone using oxygen gas supplied from the upstream side of the supply path 110 and sends the ozone-containing gas containing the ozone to the downstream side, and the supply path 110 is connected to the ozone generator 1 Downstream from 22, the system branches into multiple branch routes 112. At least one of these branch routes 112 is a processing branch route (first processing branch route 113, second processing branch route 114) connected to the processing container 10. The remaining branch routes 112 are waste branch routes 115 connected to a waste section 200 that discharges ozone-containing gas. The waste branch route 115 includes a waste flow rate adjustment section (waste MFC 150, waste flow rate adjustment valve 152) for adjusting the flow rate of the ozone-containing gas.

[0080] Furthermore, a third aspect of the present disclosure is an ozone supply method for an ozone supply system 100 having a supply path 110 for supplying gas, and an ozone generator 122 provided in the supply path 110 for generating ozone using oxygen gas supplied from the upstream side of the supply path 110 and sending the ozone-containing gas containing the ozone to the downstream side, wherein the supply path 110 branches into a plurality of branch paths 112 downstream of the ozone generator 122, and the method comprises the steps of supplying ozone-containing gas to a processing unit (processing container 10) via a processing branch path (first processing branch path 113, second processing branch path 114), which is at least one of the plurality of branch paths 112, and discharging the ozone-containing gas via a waste branch path 115, which is the remaining branch path 112, and adjusting the flow rate of the ozone-containing gas by a waste flow rate adjustment unit (waste MFC 150, waste flow rate adjustment valve 152) at the time of discharge.

[0081] In the second and third embodiments as well, the generation of ozone in the ozone generator 122 can be stabilized.

[0082] The ozone supply system 100, substrate processing apparatus 1, and ozone supply method according to the embodiments disclosed herein are illustrative and not restrictive in all respects. The embodiments can be modified and improved in various ways without departing from the scope and spirit of the appended claims. The matters described in the above embodiments can be otherwise configured and combined in a non-consistent manner.

[0083] The substrate processing apparatus 1 of this disclosure is not limited to ALD, but can be applied to any type of apparatus including Capacitively Coupled Plasma (CCP), Inductively Coupled Plasma (ICP), Radial Line Slot Antenna (RLSA), Electron Cyclotron Resonance Plasma (ECR), and Helicon Wave Plasma (HWP). Furthermore, the ozone supply system 100 is, of course, applicable to various apparatuses that use ozone-containing gas. [Explanation of symbols]

[0084] 100 Ozone Supply System 110 Supply routes 112 Branch Routes 113 First Processing Branch Route 114 Second Processing Branch Route 115 Disposal Branch Route 122 Ozone Generator 150 MFC for disposal 152 Waste flow control valve

Claims

1. Gas supply routes and The supply path includes an ozone generator that generates ozone using oxygen gas supplied from the upstream side of the supply path and sends the ozone-containing gas containing the ozone to the downstream side. The aforementioned supply path branches into multiple branch paths downstream of the ozone generator. At least one of the aforementioned multiple branch paths is a processing branch path connected to the processing unit that uses the ozone-containing gas, The aforementioned processing branch path includes a processing flow rate adjustment unit that adjusts the flow rate of the ozone-containing gas supplied to the processing unit, The remaining of the aforementioned multiple branch paths are waste branch paths connected to the waste section that discharges the ozone-containing gas. The aforementioned waste branch route includes a waste flow rate adjustment unit for adjusting the flow rate of the ozone-containing gas, The supply path upstream of the ozone generator includes an upstream flow rate adjustment unit that adjusts the flow rate of the oxygen gas. When no errors occur in the upstream flow rate adjustment unit and the processing flow rate adjustment unit, the flow rate of the ozone-containing gas in the waste flow rate adjustment unit is set to a value greater than the sum of the errors in the oxygen gas flow rate of the upstream flow rate adjustment unit and the errors in the ozone-containing gas flow rate of the processing flow rate adjustment unit. The supply path between the ozone generator and the branching point of the plurality of branch paths is provided and has a pressure sensor that approximately detects the pressure of the ozone generator, The control unit has a mechanism that, when the pressure value detected by the pressure sensor changes while supplying the ozone-containing gas to the processing unit, adjusts the flow rate of the ozone-containing gas by the waste flow rate adjustment unit without changing the flow rate of the ozone-containing gas by the processing flow rate adjustment unit. Ozone supply system.

2. The control unit controls the waste flow rate adjustment unit so that the pressure value of the pressure sensor becomes constant at the target pressure. The ozone supply system according to claim 1.

3. The control unit controls the waste flow rate adjustment unit to reduce the flow rate of the ozone-containing gas when the pressure value is lower than the target pressure, and controls the waste flow rate adjustment unit to increase the flow rate of the ozone-containing gas when the pressure value is higher than the target pressure. The ozone supply system according to claim 2.

4. The aforementioned supply route is The processing branch paths are connected to each of the processing units, The processing flow rate adjustment unit is provided in each of the plurality of processing branch paths and adjusts the flow rate of the ozone-containing gas supplied to the plurality of processing units. The ozone supply system according to any one of claims 1 to 3.

5. Multiple processing flow rate adjustment units adjust the flow rates of the ozone-containing gas to be the same for all of them. The ozone supply system according to claim 4.

6. The aforementioned waste flow rate adjustment unit is a mass flow controller. The ozone supply system according to any one of claims 1 to 5.

7. The aforementioned waste flow rate adjustment unit is a flow rate adjustment valve that adjusts the opening degree of the flow path of the waste branch route. The ozone supply system according to any one of claims 1 to 5.

8. A substrate processing apparatus comprising a processing container for processing substrates and an ozone supply system for supplying an ozone-containing gas containing ozone into the processing container, The aforementioned ozone supply system is Gas supply routes and The supply path includes an ozone generator that generates ozone using oxygen gas supplied from the upstream side of the supply path and sends the ozone-containing gas containing the ozone to the downstream side. The aforementioned supply path branches into multiple branch paths downstream of the ozone generator. At least one of the aforementioned multiple branch paths is a processing branch path connected to the processing container, The aforementioned processing branch path includes a processing flow rate adjustment unit that adjusts the flow rate of the ozone-containing gas supplied to the processing container, The remaining of the aforementioned multiple branch paths are waste branch paths connected to the waste section that discharges the ozone-containing gas. The aforementioned waste branch route includes a waste flow rate adjustment unit for adjusting the flow rate of the ozone-containing gas, The supply path upstream of the ozone generator includes an upstream flow rate adjustment unit that adjusts the flow rate of the oxygen gas. When no errors occur in the upstream flow rate adjustment unit and the processing flow rate adjustment unit, the flow rate of the ozone-containing gas in the waste flow rate adjustment unit is set to a value greater than the sum of the errors in the oxygen gas flow rate of the upstream flow rate adjustment unit and the errors in the ozone-containing gas flow rate of the processing flow rate adjustment unit. The supply path between the ozone generator and the branching point of the plurality of branch paths is provided and has a pressure sensor that approximately detects the pressure of the ozone generator, The control unit has a mechanism that adjusts the flow rate of the ozone-containing gas by the waste flow rate adjustment unit without changing the flow rate of the ozone-containing gas by the processing flow rate adjustment unit when the pressure value detected by the pressure sensor changes while supplying the ozone-containing gas to the processing container. Circuit board processing equipment.

9. Gas supply routes and An ozone supply method for an ozone supply system, comprising: an ozone generator provided in the supply path, which generates ozone using oxygen gas supplied from the upstream side of the supply path, and sends the ozone-containing gas containing the ozone to the downstream side; The aforementioned supply path branches into multiple branch paths downstream of the ozone generator. At least one of the aforementioned multiple branch paths is a processing branch path connected to the processing unit that uses the ozone-containing gas, The aforementioned processing branch path includes a processing flow rate adjustment unit that adjusts the flow rate of the ozone-containing gas supplied to the processing unit, The remaining of the aforementioned multiple branch paths are waste branch paths connected to the waste section that discharges the ozone-containing gas. The aforementioned waste branch route includes a waste flow rate adjustment unit for adjusting the flow rate of the ozone-containing gas, The supply path upstream of the ozone generator includes an upstream flow rate adjustment unit that adjusts the flow rate of the oxygen gas. When no errors occur in the upstream flow rate adjustment unit and the processing flow rate adjustment unit, the flow rate of the ozone-containing gas in the waste flow rate adjustment unit is set to a value greater than the sum of the errors in the oxygen gas flow rate of the upstream flow rate adjustment unit and the errors in the ozone-containing gas flow rate of the processing flow rate adjustment unit. In the aforementioned ozone supply method, A step of supplying the oxygen gas to the ozone generator while adjusting the flow rate of the oxygen gas by the upstream flow rate adjustment unit in the supply path upstream of the ozone generator, A step of supplying the ozone-containing gas to the processing unit while adjusting the flow rate of the ozone-containing gas in the processing branch path using the processing flow rate adjustment unit, A step of discharging the ozone-containing gas to the waste section while adjusting the flow rate of the ozone-containing gas using the waste flow rate adjustment unit in the waste branch path, The process includes a step of supplying the ozone-containing gas to the processing unit, wherein when the pressure value detected by a pressure sensor, which is provided in the supply path between the ozone generator and the branching point of the plurality of branch paths and approximately detects the pressure of the ozone generator, changes, the flow rate of the ozone-containing gas is adjusted by the waste flow rate adjustment unit without changing the flow rate of the ozone-containing gas by the processing flow rate adjustment unit. Ozone supply methods.

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