Ozone concentrator, substrate treatment device, and ozone supply method

Abstract

To provide a technique capable of stably controlling the flow rate of ozone gas, upon supplying the ozone gas.SOLUTION: The ozone concentrator according to an aspect of the present invention comprises a pump provided in a supply channel for ozone gas to flow therethrough, a flow rate controller provided in the supply channel disposed downstream relative to the pump, and a pressure controller controlling the pressure in the supply channel between the pump and the flow rate controller at a set pressure.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an ozone concentrator, a substrate processing apparatus, and an ozone supplying method. [Background technology]

[0002] An ozone gas concentrating device is known in which ozone gas generated by an ozone generator is adsorbed onto an adsorbent, and during desorption, the ozone gas is vacuum-desorbed by the action of a vacuum pump attached to a gas outlet path (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5427412 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technique that can perform stable flow rate control when supplying ozone gas. [Means for solving the problem]

[0005] An ozone concentrator according to one aspect of the present disclosure includes a pump provided in a supply flow path through which ozone gas flows, a flow rate controller provided in the supply flow path downstream of the pump, and a pressure controller that controls the pressure in the supply flow path between the pump and the flow rate controller to a set pressure. Effect of the Invention

[0006] According to the present disclosure, stable flow rate control can be performed when supplying ozone gas. [Brief description of the drawings]

[0007] [Figure 1] 1 is a diagram showing a substrate processing apparatus according to an embodiment; [Diagram 2]FIG. 1 shows the results of an example. [Diagram 3] FIG. 13 is a diagram showing the results of a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, non-limiting exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings. In all of the accompanying drawings, the same or corresponding members or parts are designated by the same or corresponding reference numerals, and duplicated descriptions will be omitted.

[0009] (Substrate processing equipment) A substrate processing apparatus 1 according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing the substrate processing apparatus 1 according to an embodiment.

[0010] The substrate processing apparatus 1 includes an ozone generator 10, an ozone concentrator 30, a processing section 50, and an apparatus controller 90.

[0011] The ozone generator 10 generates ozone gas.

[0012] The ozone concentrator 30 has a supply flow path 31, an adsorption section 32, a pump 33, a first filter 34, a buffer tank 35, a first pressure gauge 36, a flow rate controller 37, a second pressure gauge 38, a concentration meter 39, an on-off valve 40, a second filter 41, a vacuum exhaust flow path 42, an on-off valve 43, a pressure controller 44, and a control section 45.

[0013] The supply flow path 31 connects the ozone generator 10 and the processing section 50. The supply flow path 31 circulates the ozone gas generated in the ozone generator 10 and supplies it to the processing section 50. In the supply flow path 31, an adsorption section 32, a pump 33, a first filter 34, a buffer tank 35, a first pressure gauge 36, a flow rate controller 37, a second pressure gauge 38, a concentration meter 39, an on-off valve 40, and a second filter 41 are provided in this order from upstream.

[0014] The adsorption section 32 includes two adsorption columns 32a and 32b. The two adsorption columns 32a and 32b are connected in parallel to each other. In this case, while one of the adsorption columns 32a (or the adsorption column 32b) is performing a desorption operation, the other adsorption column 32b (the adsorption column 32a) is performing an adsorption operation, so that ozone gas can be continuously supplied downstream of the supply flow path 31. The adsorption section 32 may include only one adsorption column, or may include three or more adsorption columns. Each of the adsorption columns 32a and 32b is filled with an adsorbent that selectively adsorbs ozone gas. The adsorbent is, for example, silica gel. The adsorbent may be zeolite.

[0015] The pump 33 sends out the ozone gas downstream of the supply flow passage 31. The pump 33 decompresses and exhausts the ozone gas stored in the adsorption columns 32a and 32b, and supplies it downstream.

[0016] The first filter 34 filters the ozone gas flowing through the supply flow passage 31 and removes foreign matter contained in the ozone gas.

[0017] The buffer tank 35 temporarily stores the ozone gas. The buffer tank 35 averages the concentration of the ozone gas from the adsorption columns 32a and 32b when the concentration of the ozone gas changes. This allows the ozone gas to be supplied downstream of the supply flow path 31 while maintaining the concentration within a certain range.

[0018] The first pressure gauge 36 is provided in the supply flow path 31 between the buffer tank 35 and the flow rate controller 37. The first pressure gauge 36 detects the pressure of the ozone gas flowing through the supply flow path 31 between the buffer tank 35 and the flow rate controller 37. The first pressure gauge 36 detects the primary pressure of the flow rate controller 37.

[0019] The flow rate controller 37 controls the flow rate of the ozone gas flowing through the supply flow passage 31. The flow rate controller 37 is, for example, a mass flow controller (MFC).

[0020] The second pressure gauge 38 is provided in the supply flow path 31 between the flow rate controller 37 and the concentration meter 39. The second pressure gauge 38 detects the pressure of the ozone gas flowing through the supply flow path 31 between the flow rate controller 37 and the concentration meter 39. The second pressure gauge 38 detects the secondary pressure of the flow rate controller 37.

[0021] The concentration meter 39 detects the concentration of the ozone gas flowing through the supply flow passage 31 .

[0022] The on-off valve 40 is a valve that switches the flow of ozone gas on and off. When the on-off valve 40 is in an open state, the ozone gas flows to the downstream second filter 41, and when the on-off valve 40 is in a closed state, the ozone gas does not flow to the downstream second filter 41.

[0023] The second filter 41 filters the ozone gas flowing through the supply flow passage 31 and removes foreign matter contained in the ozone gas.

[0024] The vacuum exhaust flow path 42 branches off from the supply flow path 31 between the buffer tank 35 and the flow rate controller 37. The vacuum exhaust flow path 42 exhausts the ozone gas inside the supply flow path 31. An opening / closing valve 43 and a pressure controller 44 are provided in this order from upstream to downstream in the vacuum exhaust flow path 42.

[0025] The on-off valve 43 is a valve that switches the flow of ozone gas on and off. When the on-off valve 43 is in the open state, the ozone gas flows to the downstream pressure regulator 44, and when the on-off valve 43 is in the closed state, the ozone gas does not flow to the downstream pressure regulator 44.

[0026] The pressure controller 44 includes a pressure gauge that detects the primary pressure of the pressure controller 44. The pressure controller 44 controls the pressure detected by the built-in pressure gauge to a set pressure. This adjusts the pressure of the vacuum exhaust flow path 42 upstream of the pressure controller 44 to the set pressure. When the on-off valve 43 is open, the vacuum exhaust flow path 42 upstream of the pressure controller 44 communicates with the supply flow path 31 between the buffer tank 35 and the flow controller 37. Therefore, when the on-off valve 43 is open, the pressure of the supply flow path 31 between the buffer tank 35 and the flow controller 37 is adjusted to the set pressure. As a result, the primary pressure of the flow controller 37 is stabilized, so that stable flow control can be performed when supplying ozone gas to the processing unit 50. The pressure controller 44 is, for example, a pressure control valve (PCV: Pressure Control Valve).

[0027] The pressure controller 44 may control the pressure detected by the first pressure gauge 36 to a set pressure. In this case, the pressure in the supply flow path 31 between the buffer tank 35 and the flow rate controller 37 is adjusted to the set pressure in the same manner as described above. As a result, the primary pressure of the flow rate controller 37 is stabilized, so that stable flow rate control can be performed when supplying ozone gas to the treatment unit 50.

[0028] The set pressure is, for example, a fixed value determined in advance. The fixed value may be equal to or greater than the total pressure of the secondary pressure of the flow controller 37 that can be obtained when the flow controller 37 is changed from the minimum controllable flow rate to the maximum controllable flow rate, and the minimum required differential pressure of the flow controller 37. In this case, even if the set flow rate of the flow controller 37 is changed to any flow rate from the minimum controllable flow rate to the maximum controllable flow rate, stable flow rate control can be performed when supplying ozone gas to the processing unit 50. The secondary pressure of the flow controller 37 can be detected by the second pressure gauge 38.

[0029] The set pressure may be a variable value determined according to the pressure detected by the second pressure gauge 38. The set pressure may be the sum of the pressure detected by the second pressure gauge 38 and the minimum required differential pressure of the flow rate controller 37. In this case, the secondary pressure of the pump 33 can be reduced. This improves the life of the pump 33.

[0030] The control unit 45 may control the set pressure of the pressure controller 44 to be the sum of the pressure detected by the second pressure gauge 38 and the minimum required differential pressure of the flow controller 37. When the set flow rate of the flow controller 37 is large, the pressure detected by the second pressure gauge 38 becomes high, and when the set flow rate of the flow controller 37 is small, the pressure detected by the second pressure gauge 38 becomes low. In this way, the pressure detected by the second pressure gauge 38 varies depending on the set flow rate of the flow controller 37. Therefore, by the control unit 45 controlling the set pressure of the pressure controller 44 to be the sum of the pressure detected by the second pressure gauge 38 and the minimum required differential pressure of the flow controller 37, the secondary pressure of the pump 33 can be reduced regardless of the set flow rate of the flow controller 37.

[0031] The processing section 50 includes a processing container 51 , a holding section 52 , an inlet flow path 53 , an on-off valve 54 , a discharge flow path 55 , and an on-off valve 56 .

[0032] The processing container 51 is a container having a processing space formed therein capable of accommodating a substrate W. The substrate W is processed in the processing space. The substrate W is, for example, a semiconductor wafer.

[0033] The holder 52 is provided inside the processing vessel 51. The holder 52 horizontally holds, for example, one substrate W. The holder 52 may be capable of holding two or more substrates W horizontally.

[0034] The introduction flow path 53 connects the supply flow path 31 and the processing vessel 51. The introduction flow path 53 introduces the ozone gas from the supply flow path 31 into the processing vessel 51. The introduction flow path 53 is provided with an on-off valve .

[0035] The on-off valve 54 is a valve that switches the flow of ozone gas on and off. When the on-off valve 54 is in an open state, the ozone gas flows into the downstream processing vessel 51, and when the on-off valve 54 is in a closed state, the ozone gas does not flow into the downstream processing vessel 51.

[0036] The exhaust flow passage 55 is connected to the processing vessel 51. The exhaust flow passage 55 exhausts the ozone gas inside the processing vessel 51. An opening and closing valve 56 is provided in the exhaust flow passage 55.

[0037] The on-off valve 56 is a valve that switches the flow of ozone gas on and off. When the on-off valve 56 is in an open state, the ozone gas flows into the downstream exhaust flow path 55, and when the on-off valve 56 is in a closed state, the ozone gas does not flow into the downstream exhaust flow path 55.

[0038] The equipment controller 90 is, for example, a computer, and includes a calculation unit 91 and a storage unit 92. The storage unit 92 stores programs for controlling various processes executed in the substrate processing apparatus 1. The calculation unit 91 controls the operation of the substrate processing apparatus 1 by reading and executing the programs stored in the storage unit 92. The programs may be recorded in a computer-readable storage medium and installed from the storage medium to the storage unit 92 of the equipment controller 90. Examples of computer-readable storage media include a hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnet optical disk (MO), and a memory card. Instead of the control unit 45, the equipment controller 90 may control the set pressure of the pressure controller 44 to be the sum of the pressure detected by the second pressure gauge 38 and the minimum required differential pressure of the flow rate controller 37.

[0039] (Ozone supply method) An example of a method in which the ozone concentrator 30 supplies ozone gas to the processing unit 50 will be described. When the ozone concentrator 30 supplies ozone gas to the processing unit 50, the control unit 45 controls the on-off valve 43 to an open state, and the pressure controller 44 controls the pressure detected by the built-in pressure gauge or the pressure detected by the first pressure gauge 36 to a set pressure. In this case, the pressure of the supply flow path 31 between the buffer tank 35 and the flow rate controller 37 is adjusted to the set pressure. Therefore, the primary pressure of the flow rate controller 37 is stabilized, so that stable flow rate control can be performed when supplying ozone gas to the processing unit 50.

[0040] When the ozone concentrator 30 supplies ozone gas to the treatment unit 50, the control unit 45 may control the set pressure of the pressure controller 44 to be the sum of the pressure detected by the second pressure gauge 38 and the minimum required pressure of the flow rate controller 37. In this case, the secondary pressure of the pump 33 can be lowered. This improves the life of the pump 33.

[0041] (Evaluation Results) In the substrate processing apparatus 1 according to the embodiment, changes in the primary pressure of the flow controller 37 and changes in the flow rate of ozone gas were measured when ozone gas was supplied to the processing unit 50 while changing the set flow rate of the flow controller 37 (Example). In the Example, the pressure controller 44 supplied ozone gas to the processing unit 50 while controlling the pressure detected by the first pressure gauge 36 to the set pressure. At this time, the control unit 45 controlled the set pressure to be the sum of the pressure detected by the second pressure gauge 38 and the minimum required pressure of the flow controller 37.

[0042] For comparison, in a substrate processing apparatus (not shown) in which the pressure controller 44 is removed from the substrate processing apparatus 1, changes in the primary pressure of the flow controller 37 and changes in the flow rate of the ozone gas were measured when ozone gas was supplied to the processing unit 50 while changing the set flow rate of the flow controller 37 (Comparative Example). In the Comparative Example, ozone gas was supplied to the processing unit 50 while controlling the primary pressure of the flow controller 37 to be equal to or lower than the threshold pressure by switching the on-off valve 43 from a closed state to an open state when the pressure detected by the first pressure gauge 36 exceeded the threshold pressure.

[0043] Fig. 2 is a diagram showing the results of an embodiment. Fig. 3 is a diagram showing the results of a comparative example. In Fig. 2 and Fig. 3, the horizontal axis indicates time [seconds], the vertical axis on the left indicates the pressure (primary pressure of flow rate controller 37) [kPaA] detected by the first pressure gauge 36, and the vertical axis on the right indicates the flow rate [SLM] detected by the flow rate controller 37. In Fig. 3, the threshold pressure is indicated by a dashed line.

[0044] As shown in Fig. 2, in the embodiment, it can be seen that stable flow control is performed without flow rate fluctuations even when the set flow rate of the flow rate controller 37 is changed. This is believed to be because the primary pressure of the flow rate controller 37 is stabilized by pressure control by the pressure controller 44. In contrast, as shown in Fig. 3, in the comparative example, it can be seen that the flow rate fluctuations are large after the set flow rate of the flow rate controller 37 is changed. This is believed to be because the pressure fluctuations are large when the on-off valve 43 is opened and closed, and the primary pressure of the flow rate controller 37 fluctuates with the opening and closing of the on-off valve 43.

[0045] 2, in the embodiment, when the set flow rate of the flow controller 37 is changed in the range of 5 SLM to 10 SLM, the primary pressure of the flow controller 37 is 80 kPaA to 120 kPaA. In contrast, in the comparative example, when the set flow rate of the flow controller 37 is changed in the range of 5 SLM to 10 SLM, the primary pressure of the flow controller 37 is 130 kPaA to 150 kPaA. This result shows that in the embodiment, the primary pressure of the flow controller 37, i.e., the secondary pressure of the pump 33, can be lowered compared to the comparative example.

[0046] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0047] 30 Ozone Concentrator 31 Supply Channel 33 Pump 37 Flow Controller 44 Pressure Controller

Claims

1. a pump provided in a supply flow path through which the ozone gas flows; a flow rate controller provided in the supply flow path downstream of the pump; a pressure controller that controls the pressure of the supply flow path between the pump and the flow rate controller to a set pressure; 1. An ozone concentrator comprising:

2. The pressure controller is provided in a vacuum exhaust passage branched from the supply passage between the pump and the flow rate controller.

2. The ozone concentrator of claim 1.

3. The set pressure is a predetermined fixed value.

3. An ozone concentrator according to claim 1 or 2.

4. a pressure gauge for detecting a pressure in the supply flow path downstream of the flow rate controller; The set pressure is a variable value determined according to the pressure detected by the pressure gauge.

3. An ozone concentrator according to claim 1 or 2.

5. The pressure sensor further includes a control unit that controls the set pressure so that the set pressure is equal to a sum of the pressure detected by the pressure gauge and a minimum required differential pressure of the flow rate controller.

5. The ozone concentrator of claim 4.

6. A processing section for processing a substrate; an ozone concentrator connected to the processing section; Equipped with The ozone concentrator comprises: a pump provided in a supply flow path through which the ozone gas flows; a flow rate controller provided in the supply flow path downstream of the pump; a pressure controller that controls the pressure of the supply flow path between the pump and the flow rate controller to a set pressure; having Substrate processing equipment.

7. a pump provided in a supply flow path through which the ozone gas flows; a flow rate controller provided in the supply flow path downstream of the pump; a pressure controller that controls the pressure of the supply flow path between the pump and the flow rate controller to a set pressure; a pressure gauge for detecting a pressure in the supply flow path downstream of the flow rate controller; An ozone supplying method for supplying ozone gas by an ozone concentrator having and controlling the set pressure to be a sum of the pressure detected by the pressure gauge and a minimum required pressure of the flow rate controller. Ozone supply method.

Images