JP7203975B2 - SUBSTRATE PROCESSING SYSTEM AND PROCESSING LIQUID PREPARATION METHOD - Google Patents

Description

The present disclosure relates to a substrate processing system and a processing liquid preparation method.

A substrate processing system circulates a processing liquid stored in a tank through a circulation line, supplies the processing liquid to a processing unit through a line branched from the circulation line, and processes a substrate using the processing liquid. It is known (see patent document 1 and patent document 2). In such a substrate processing system, the processing liquid in the tank is usually adjusted to a desired concentration suitable for substrate processing, and the processing liquid after the concentration adjustment is sent from the tank to the processing unit through the circulation line.

In such a substrate processing system, substrate processing may be performed using a low-concentration processing liquid (for example, a concentration of 20 ppm or less). Particularly in recent years, substrate processing using a processing liquid with an ultra-low concentration (for example, a concentration of 3 ppm or less) has come to be implemented. Also in these cases, the processing liquid in the tank is adjusted to a desired low concentration or ultra-low concentration. However, in order to adjust the concentration of the processing liquid in the tank to a low concentration or an ultra-low concentration, strict concentration control is required, which requires a considerable amount of labor and time.

In addition, even a small amount of processing liquid having a low concentration or an ultra-low concentration is mixed with processing liquids having different concentrations, so that the concentration easily changes. Therefore, it is not easy to stably maintain the concentration of the processing liquid at a desired low concentration or ultra-low concentration. In particular, the processing liquid may remain in the flow path of the substrate processing system. Such residual processing liquid may occur even after liquid exchange processing and drain processing are performed. If the concentration of the residual processing liquid is different from the desired concentration (e.g., higher than the desired ultra-low concentration), even if the processing liquid in the tank is adjusted to the desired concentration once, the processing liquid will not reach the processing unit from the tank. During this period, the residual processing liquid is mixed into the processing liquid and the concentration of the processing liquid fluctuates.

JP 2015-220318 A JP 2017-208418 A

The present disclosure provides a technique capable of rapidly adjusting a processing liquid to a desired concentration in a substrate processing system.

According to one aspect of the present disclosure, a substrate processing system that processes a substrate using a processing liquid containing a first liquid and a second liquid, a processing liquid supply system that supplies the processing liquid to the substrate processing system, a first a processing liquid adjustment system for supplying at least one of the first liquid, the second liquid, and the processing liquid to the processing liquid supply system; and a controller, wherein the processing liquid supply system is connected to the processing liquid adjustment system. , a tank for storing the processing liquid, a circulation line connected to the tank and through which the processing liquid exiting the tank and returning to the tank flows, a branch line connected to the circulation line and the substrate processing system, and the processing liquid flowing through the circulation line. a circulator, a drain line through which the processing liquid discharged from at least one of the tank and the circulation line flows, a drain adjustment unit that adjusts the discharge of the processing liquid through the drain line, the tank, the circulation line, the tank and a concentration sensor for measuring the concentration of the treatment liquid in at least one of the concentration measurement line connected to the first liquid and the concentration measurement line connected to the circulation line. and a supply regulator for regulating the supply of at least one of the second liquid and the processing liquid to the tank, the control section controlling the circulator to supply a certain amount of the processing liquid in the tank and the circulation line. Based on the measurement result of the concentration sensor after circulation, the drain adjustment unit is controlled to adjust the discharge of the treatment liquid, and the supply adjustment unit is controlled to select one of the first liquid, the second liquid and the treatment liquid. A substrate processing system that regulates the supply of at least one tank.

According to the present disclosure, the processing liquid can be rapidly adjusted to a desired ultra-low concentration in a substrate processing system.

FIG. 1 is a diagram showing an example of a schematic configuration of a substrate processing system. FIG. 2 is a diagram illustrating an example of a schematic configuration of a processing unit; FIG. 3 is a diagram showing a schematic configuration example of a substrate processing system, a processing liquid supply system, and a processing liquid adjustment system of the substrate processing system according to the first embodiment. FIG. 4 is a flow chart showing an example of the treatment liquid preparation method. FIG. 5 is a diagram showing a schematic configuration example of a substrate processing system, a processing liquid supply system, and a processing liquid adjustment system of a substrate processing system according to the second embodiment. FIG. 6 is a diagram showing a schematic configuration example of a substrate processing system, a processing liquid supply system, and a processing liquid adjustment system of a substrate processing system according to the third embodiment.

Embodiments of a substrate processing system and a processing liquid preparation method will be described with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of a substrate processing system according to this embodiment. Hereinafter, in order to clarify the positional relationship, the X-axis, Y-axis and Z-axis are defined to be orthogonal to each other, and the positive direction of the Z-axis is defined as the vertically upward direction.

A substrate processing system 1 shown in FIG. 1 includes a loading/unloading station 2 and a processing station 3 . The loading/unloading station 2 and the processing station 3 are provided adjacently.

The loading/unloading station 2 includes a carrier placement section 11 and a transport section 12 . A plurality of carriers C for accommodating a plurality of substrates, in this embodiment, semiconductor wafers (hereinafter referred to as wafers W) in a horizontal state are mounted on the carrier mounting portion 11 .

The transfer section 12 is provided adjacent to the carrier mounting section 11 and includes a substrate transfer device 13 and a transfer section 14 therein. The substrate transfer device 13 includes a wafer holding mechanism that holds the wafer W. As shown in FIG. In addition, the substrate transfer device 13 can move in the horizontal direction and the vertical direction and can rotate around the vertical axis, and transfers the wafer W between the carrier C and the transfer section 14 using the wafer holding mechanism. conduct.

The processing station 3 is provided adjacent to the transport section 12 . The processing station 3 comprises a transport section 15 and a plurality of processing units 16 . A plurality of processing units 16 are provided side by side on both sides of the transport section 15 .

The transport unit 15 includes a substrate transport device 17 inside. The substrate transfer device 17 includes a wafer holding mechanism that holds the wafer W. As shown in FIG. In addition, the substrate transfer device 17 can move in the horizontal direction and the vertical direction and can rotate around the vertical axis, and transfers the wafer W between the delivery section 14 and the processing unit 16 using a wafer holding mechanism. I do.

The processing unit 16 performs predetermined substrate processing on the wafer W transferred by the substrate transfer device 17 .

The substrate processing system 1 also includes a control device 4 . Control device 4 is, for example, a computer, and includes control unit 18 and storage unit 19 . The storage unit 19 stores programs for controlling various processes executed in the substrate processing system 1 . The control unit 18 controls the operation of the substrate processing system 1 by reading and executing programs stored in the storage unit 19 .

The program may be recorded in a computer-readable storage medium and installed in the storage unit 19 of the control device 4 from the storage medium. Examples of computer-readable storage media include hard disks (HD), flexible disks (FD), compact disks (CD), magnet optical disks (MO), and memory cards.

In the substrate processing system 1 configured as described above, first, the substrate transfer device 13 of the loading/unloading station 2 takes out the wafer W from the carrier C placed on the carrier platform 11, and receives the taken out wafer W. It is placed on the transfer section 14 . The wafer W placed on the transfer section 14 is taken out from the transfer section 14 by the substrate transfer device 17 of the processing station 3 and carried into the processing unit 16 .

The wafer W loaded into the processing unit 16 is processed by the processing unit 16 , then unloaded from the processing unit 16 by the substrate transfer device 17 and placed on the transfer section 14 . Then, the processed wafer W placed on the transfer section 14 is returned to the carrier C on the carrier placement section 11 by the substrate transfer device 13 .

Next, a schematic configuration of the processing unit 16 will be described with reference to FIG. FIG. 2 is a diagram showing a schematic configuration of the processing unit 16. As shown in FIG.

As shown in FIG. 2 , the processing unit 16 includes a chamber 20 , a substrate holding mechanism 30 , a processing fluid supply section 40 and a collection cup 50 .

The chamber 20 accommodates a substrate holding mechanism 30 , a processing fluid supply section 40 and a collection cup 50 . An FFU (Fan Filter Unit) 21 is provided on the ceiling of the chamber 20 . FFU 21 forms a downflow in chamber 20 .

The substrate holding mechanism 30 includes a holding portion 31 , a support portion 32 and a driving portion 33 . The holding part 31 holds the wafer W horizontally. The column portion 32 is a member extending in the vertical direction, the base end portion of which is rotatably supported by the drive portion 33, and the tip portion of which supports the holding portion 31 horizontally. The drive section 33 rotates the support section 32 around the vertical axis. The substrate holding mechanism 30 rotates the holding part 31 supported by the supporting part 32 by rotating the supporting part 32 using the driving part 33, thereby rotating the wafer W held by the holding part 31. .

The processing fluid supply unit 40 supplies the wafer W with processing fluid. The processing fluid supply 40 is connected to a processing fluid supply 70 .

The collection cup 50 is arranged to surround the holding portion 31 and collects the processing liquid scattered from the wafer W due to the rotation of the holding portion 31 . A drain port 51 is formed at the bottom of the recovery cup 50 , and the processing liquid collected by the recovery cup 50 is discharged to the outside of the processing unit 16 through the drain port 51 . An exhaust port 52 is formed at the bottom of the collection cup 50 to discharge the gas supplied from the FFU 21 to the outside of the processing unit 16 .

Next, concentration adjustment, circulation and supply of the processing liquid in the substrate processing system 1 will be described.

In each of the following embodiments, the case of adjusting the concentration of the treatment liquid to an ultra-low concentration (for example, a concentration of 3 ppm or less) will be described, but the concentration of the treatment liquid is adjusted to another concentration (for example, a concentration higher than 3 ppm). In any case, the following embodiments are applicable.

[First embodiment]
FIG. 3 is a diagram showing a schematic configuration example of the substrate processing system 21, the processing liquid supply system 22, and the processing liquid adjustment system 23 of the substrate processing system 1 according to the first embodiment.

The substrate processing system 1 of this embodiment includes a substrate processing system 21, a processing liquid supply system 22, a processing liquid adjustment system 23, and a control section 18 (see FIG. 1).

The substrate processing system 21 processes the wafer W using a processing liquid containing a first liquid (ammonium hydroxide (ammonia water) in this example) and a second liquid (DIW (deionized water) in this example). (for example, cleaning). The specific components contained in the treatment liquid are not limited, and the components contained in the treatment liquid may be exactly the same as or different from the components contained in the first liquid or the second liquid.

The processing liquid supply system 22 supplies the processing liquid to the substrate processing system 21 . The treatment liquid adjustment system 23 supplies at least one of the first liquid, the second liquid, and the treatment liquid to the treatment liquid supply system 22 . The control unit 18 is connected to constituent elements of the substrate processing system 21, the processing liquid supply system 22, and the processing liquid adjustment system 23, such as on-off valves, pumps, flowmeters, concentration sensors, and the like, and controls the operating states of the respective constituent elements. and receive measurement results from each component.

A substrate processing system 21 shown in FIG. 3 has a plurality of processing units 16 and a main return line 41 . Each processing unit 16 has the structure shown in FIG. 2 described above, and FIG. 3 shows a simplified configuration of each processing unit 16 . The processing fluid supply unit 40 of each processing unit 16 is connected to the main branch line 37, and supplies the processing liquid sent through the main branch line 37 to the processing surface of the wafer W supported by the substrate holding mechanism 30. supply.

The main branch line 37 is provided with a plurality of on-off valves 55l assigned to the plurality of processing units 16, respectively. Each on-off valve 55l opens and closes under the control of the control unit 18, and adjusts the flow rate of the processing liquid from the main branch line 37 to the corresponding processing unit 16 (that is, the processing fluid supply unit 40) (checks whether or not the processing liquid is supplied). including). The main return line 41 is connected to the drain port 51 (see FIG. 2) of each processing unit 16 and to the tank 35 to guide the processing liquid discharged from each processing unit 16 into the tank 35 .

The substrate processing system 21 shown in FIG. 3 is merely an example, and the substrate processing system 21 may have other configurations. For example, although four processing units 16 are shown in FIG. may have. Moreover, even if a plurality of main branch lines 37 are directly connected to the circulation line 36 and these main branch lines 37 are connected to each of the plurality of processing units 16 (that is, the plurality of processing fluid supply units 40). good. In addition, a plurality of portions of the main return line 41 assigned to each of the plurality of processing units 16 are provided with on-off valves (not shown), and discharge of the processing liquid to the main return line 41 for each processing unit 16 is controlled by the opening and closing valves. It may be controlled by a valve. A drain line (not shown) may be connected to each processing unit 16 . The drain line and the main return line 41 may be connected to each processing unit 16 via a channel switching section (not shown). Under the control of the control section 18 , the flow path switching section can flow the processing liquid discharged from each processing unit 16 to the drain line or the main return line 41 .

A sub-circulation line (not shown) provided to correspond to each processing unit 16 and connected to the main branch line 37 and the main return line 41 so as to bypass the corresponding processing unit 16 A line (not shown) may be installed. For example, each on-off valve 55l is configured as a flow path switching device such as a three-way valve, and for each on-off valve 55l, a flow path (main branch line 37) connected to the corresponding processing fluid supply unit 40 and a corresponding sub A circulation line may be connected. In this case, each opening/closing valve 55l is controlled by the control unit 18 to supply the processing liquid sent from the main branch line 37 on the upstream side to the corresponding processing fluid supply unit 40 via the main branch line 37 on the downstream side. It is possible to switch between a mode of direct flow and a mode of flow to the corresponding sub-circulation line.

In this specification, unless otherwise specified, the terms "upstream" and "downstream" refer to fluids (in this embodiment, the first liquid, the second liquid and the processing liquid) flowing through the flow path of the substrate processing system 1. based on the flow direction of

The processing liquid supply system 22 shown in FIG. 3 has a tank 35 and a circulation line 36 . The tank 35 is connected to the processing liquid adjustment system 23 (especially the main supply line 71), is supplied with the first liquid, the second liquid and/or the processing liquid from the processing liquid adjustment system 23, and stores the processing liquid. A circulation line 36 is connected to the tank 35 and carries the processing liquid leaving the tank 35 and returning to the tank 35 . A main branch line 37 is connected to the circulation line 36 and the substrate processing system 21 (especially the processing fluid supply section 40 of each processing unit 16).

A circulation pump (circulator) 42, a filter 43, a heater 44, a flow meter 45, and a plurality of on-off valves 55h, 55i, 55j are sequentially provided in the circulation line 36 from upstream to downstream.

A circulation pump 42 causes the processing liquid to flow through the circulation line 36 . The circulation pump 42 shown in FIG. 3 causes the processing liquid in the circulation line 36 to flow counterclockwise. The processing liquid flowing into the circulation line 36 from the tank 35 is returned to the tank 35 again through the circulation pump 42, the filter 43, the heater 44, the flow meter 45 and the plurality of on-off valves 55h, 55i, 55j.

Filter 43 removes foreign matter and air bubbles from the processing liquid. As the processing liquid passes through the filter 43, foreign matter and air bubbles are removed from the processing liquid. The illustrated filter 43 is provided downstream of the circulation pump 42 in the circulation line 36 and arranged in the vicinity of the circulation pump 42 . Since the processing liquid that has flowed into the tank 35 through the circulation line 36 is stored in the tank 35, the processing liquid that has flowed out of the tank 35 into the circulation line 36 may contain foreign matter such as deposits. Also, the operation of the circulation pump 42 may cause air bubbles to mix in the processing liquid. In order to effectively remove such foreign substances and air bubbles from the processing liquid, it is preferable to arrange a filter 43 downstream of and near the tank 35 and the circulation pump 42 . In addition, from the viewpoint of allowing a sufficient amount of treatment liquid to flow vigorously into the filter 43 , the filter 43 is preferably arranged downstream and in the vicinity of the circulation pump 42 .

The heater 44 applies thermal energy to the processing liquid in the circulation line 36 under the control of the control unit 18 to raise the temperature of the processing liquid. The flow meter 45 measures the flow rate of the treatment liquid and transmits the measurement result to the control section 18 . The on-off valves 55h, 55i, and 55j are provided downstream of the filter 43 and the heater 44 in the circulation line 36, and their opening degrees are adjusted under the control of the controller 18. The flow rate of the processing liquid in the circulation line 36 is adjusted according to the opening degrees of the on-off valves 55h, 55i, and 55j. In particular, the on-off valve 55h and the on-off valve 55i provided adjacent to the connecting portion of the circulation line 36 and the main branch line 37 are liquid supply adjustment units for adjusting the supply of the processing liquid from the circulation line 36 to the substrate processing system 21. function as For example, the supply of the processing liquid to the main branch line 37 and the substrate processing system 21 is stopped by closing the on-off valve 55h provided on the upstream side of the portion of the circulation line 36 to which the main branch line 37 is connected. can be done. The processing liquid is returned to the tank 35 via the circulation line 36 by closing the on-off valves 55i and 55j provided on the downstream side of the portion of the circulation line 36 to which the main branch line 37 is connected. can stop.

A concentration measurement line 39 is connected to the circulation line 36 and the tank 35 . One end of the illustrated concentration measurement line 39 is connected to a portion (especially a portion between the filter 43 and the heater 44) of the circulation line 36 between the filter 43 and the on-off valve 55h (liquid supply adjustment unit). ing. The other end of the illustrated concentration measurement line 39 is directly connected to the tank 35 . The concentration measurement line 39 is provided with an on-off valve 55 k and a concentration sensor 46 .

The concentration sensor 46 measures the concentration of the processing liquid flowing through the concentration measurement line 39 (in this example, the concentration of the component contained in the first liquid (that is, ammonia concentration)) and transmits the measurement result to the control unit 18 . A specific configuration of the concentration sensor 46 is not limited, and typically a sensor that performs measurement based on the correlation between the conductivity and concentration of the solution can be used as the concentration sensor 46 . The on-off valve 55k opens and closes under the control of the control unit 18, and adjusts the amount of inflow of the processing liquid from the circulation line 36 to the concentration measurement line 39 (including the presence or absence of inflow of the processing liquid). From the viewpoint of accurately measuring the concentration of the processing liquid, the concentration sensor 46 preferably measures the processing liquid from which foreign matter and air bubbles have been removed. preferably.

Note that the concentration sensor 46 of the processing liquid supply system 22 is not limited to the illustrated form. Although not shown, the concentration sensor 46 detects the processing liquid in at least one of the tank 35, the circulation line 36, the concentration measurement line connected to the tank 35, and the concentration measurement line 39 connected to the circulation line 36, for example. may be measured. Also, the processing liquid supply system 22 may have a plurality of concentration sensors. For example, even if concentration measurement lines 39 and 39a branch from the circulation line 36 upstream and downstream of the heater 44, respectively, and concentration sensors 46 and 46a are provided in these concentration measurement lines 39 and 39a, respectively. good. When a plurality of density sensors are provided, by changing the measurable density range for each density sensor, it is possible to accurately measure a wide range of density as a whole.

The processing liquid supply system 22 further includes a drain line 38 through which the processing liquid discharged from the processing liquid supply system 22 flows, and on-off valves 55e, 55f, and 55g (drain adjustment unit). The drain line 38 allows the processing liquid discharged from at least one of the tank 35 and the circulation line 36 to flow. The processing liquid supply system 22 shown in FIG. 3 has three drain lines 38, each of which is provided with on-off valves 55e, 55f, and 55g. A drain line 38 provided with an on-off valve 55 e is directly connected to the tank 35 . A drain line 38 provided with an on-off valve 55 f is connected to a portion of the circulation line 36 between the tank 35 and the circulation pump 42 . A drain line 38 provided with an on-off valve 55 g is connected to a portion of the circulation line 36 between the circulation pump 42 and the filter 43 . Each drain line 38 may or may not merge with other drain lines 38 .

The processing liquid adjustment system 23 has supply adjustment units (that is, on-off valves 55a, 55b, and 55d). The supply adjustment units (on-off valves 55a, 55b, 55d) contain at least one of the first liquid (ammonium hydroxide), the second liquid (DIW), and the processing liquid (mixed liquid of ammonium hydroxide and DIW). supply to tank 35 of The illustrated processing liquid adjustment system 23 has a main replenishment line 71 connected to the tank 35 and a sub-replenishment line 72 joining the main replenishment line 71 .

One end of the main supply line 71 is connected to the second liquid supply source 62 and the other end is connected to the tank 35 . The main supply line 71 is provided with an on-off valve 55a, a concentration sensor 64, and an on-off valve 55d in this order from the upstream side to the downstream side.

One end of the sub supply line 72 is connected to the first liquid supply source 61 and the other end is connected to the main supply line 71 . The illustrated sub supply line 72 is connected to a portion of the main supply line 71 between the concentration sensor 64 and the on-off valve 55a. A flow meter 63 and an on-off valve 55b are sequentially provided in the sub supply line 72 from the upstream side to the downstream side.

A drain line 38 is connected to a portion of the main replenishment line 71 downstream of the concentration sensor 64 (a portion between the concentration sensor 64 and the on-off valve 55d in the illustrated example). is provided with an on-off valve 55c. The on-off valve 55c opens and closes under the control of the control unit 18 to adjust discharge of the processing liquid from the processing liquid adjustment system 23 (especially the main replenishment line 71) through the drain line .

As described above, in the substrate processing system 1 shown in FIG. 3, at least a part of the processing liquid supply system 22 and the processing liquid adjustment system 23 corresponds to the processing fluid supply source 70 shown in FIG. A combination of the processing liquid supply system 22 and the processing liquid adjustment system 23 is also called a circulation cabinet 24, and the circulation cabinet 24 can be constructed integrally. In this embodiment, one circulation cabinet 24 is connected to one substrate processing system 21 .

The control unit 18 (see FIG. 1) controls the drain adjustment unit (the on-off valve 55e, the on-off valve 55f and/or the on-off valve 55g) based on the measurement result of the concentration sensor 46, and the processing liquid supply system 22 (the tank 35 and /or regulate the discharge of processing liquid from the circulation line 36); Further, the control unit 18 controls the supply adjustment units (on-off valves 55a, 55b, 55d) based on the measurement result of the concentration sensor 46, and controls at least one of the first liquid, the second liquid, and the processing liquid. Adjust the supply to tank 35 . In particular, the control unit 18 of the present embodiment controls the circulation pump 42 to circulate a certain amount of the processing liquid in the tank 35 and the circulation line 36, and then discharges the processing liquid and supplies DIW to the tank 35. I do.

Next, an example of a processing liquid preparation method performed by the substrate processing system 1 (particularly, the processing liquid supply system 22 and the processing liquid adjustment system 23) will be described.

According to the processing liquid preparation method described below, first, a processing liquid having a concentration higher than a target concentration is stored in the tank 35, and the high-concentration processing liquid is circulated in the flow path including the tank 35 and the circulation line 36. Thereafter, the concentration of the processing liquid in the processing liquid supply system 22 is diluted by discharging the processing liquid from the tank 35 and/or the circulation line 36 and supplying DIW to the tank 35 . By repeating this series of treatments as necessary, the concentration of the treatment liquid in the treatment liquid supply system 22 is adjusted to a desired ultra-low concentration.

FIG. 4 is a flow chart showing an example of the treatment liquid preparation method. Although detailed description is omitted, the control unit 18 appropriately controls elements such as on-off valves included in the substrate processing system 1 in order to appropriately execute the following processing.

First, the control unit 18 controls the supply adjustment units (on-off valves 55a, 55b, 55d) to supply a processing liquid having a concentration higher than the target concentration (eg, 3 ppm) (eg, a processing liquid having a concentration of about 20 ppm) to the tank 35. (S1 in FIG. 4). By supplying the high-concentration processing liquid from the processing liquid adjustment system 23 to the tank 35 , the concentration of the processing liquid stored in the tank 35 becomes higher than the target concentration of the processing liquid. Typically, the on-off valve 55a, the on-off valve 55b, and the on-off valve 55d are opened, and the ammonium hydroxide from the first liquid supply source 61 and the DIW from the second liquid supply source 62 join in the main supply line 71, It is additionally supplied to the tank 35 via the on-off valve 55d. However, the on-off valve 55a may be closed, the on-off valves 55b and 55d may be opened, and only the ammonium hydroxide from the first liquid supply source 61 may be additionally supplied to the tank 35 via the on-off valve 55d.

After that, the controller 18 controls the circulation pump 42 to circulate a certain amount of the treatment liquid in at least the tank 35 and the circulation line 36 (S2). As a result, the residual processing liquid in the processing liquid supply system 22 (for example, the circulation line 36, the circulation pump 42, the filter 43, the heater 44, the flow meter 45, and the on-off valves 55h, 55i, 55j) is swept away by the circulating processing liquid, returned to As a result, the concentration of the processing liquid in the entire processing liquid supply system 22 (for example, the processing liquid in the tank 35 and the circulation line 36) is made uniform. The circulation time of the treatment liquid in this case is not limited. From the viewpoint of eliminating the difference in concentration of the processing liquid throughout the processing liquid supply system 22, the circulation time of the processing liquid should be sufficient for the processing liquid remaining in the processing liquid supply system 22 to be returned to the tank 35 together with the circulating processing liquid. A period of time (for example, about 30 seconds) is preferable.

In the case where the substrate processing system 21 has a flow channel configuration that allows the processing liquid to circulate, the processing liquid may also be circulated in the substrate processing system 21 when the processing liquid is circulated in the processing liquid supply system 22 (S2). For example, when the substrate processing system 21 has the sub-circulation line (not shown), the tank 35 , the circulation line 36 , the main branch line 37 , the sub-circulation line and the main return line 41 may also circulate the processing liquid. By circulating the processing liquid in the substrate processing system 21, the processing liquid remaining in the substrate processing system 21 is also collected in the tank 35 together with the circulating processing liquid. Thereby, the concentration of the processing liquid can be made uniform in the substrate processing system 21 and the processing liquid supply system 22 .

After the processing liquid is circulated as described above, the concentration of the processing liquid measured by the concentration sensor 46 is obtained by the controller 18 . Then, the controller 18 determines whether the concentration of the treatment liquid measured by the concentration sensor 46 has reached the target concentration (S3). The target density may be a preset specific value, but is typically preset to a range of densities.

When the concentration of the treatment liquid measured by the concentration sensor 46 reaches the target concentration (Y in S3), the preparation of the treatment liquid having the desired concentration is completed, and the treatment liquid preparation process ends.

When the concentration of the processing liquid measured by the concentration sensor 46 does not reach the target concentration (N in S3), part of the processing liquid in the processing liquid supply system 22 is discharged through the drain line 38 (S4), and the processing is completed. DIW is supplied from the liquid adjustment system 23 to the tank 35 (S5). That is, the control unit 18 controls the drain adjustment unit (the on-off valve 55e, the on-off valve 55f and/or the on-off valve 55g) based on the measurement result of the concentration sensor 46, and the drain adjustment unit adjusts the discharge of the processing liquid. The control unit 18 also controls the supply adjustment unit (on-off valves 55a, 55b, 55d) based on the measurement results of the concentration sensor 46, and the supply adjustment unit adjusts the supply of DIW to the tank 35. FIG. As a result, the concentration of the processing liquid in the tank 35 is diluted and brought closer to the target concentration.

From the viewpoint of efficiently diluting the concentration of the processing liquid, it is preferable to supply the DIW to the tank 35 after the discharge of the processing liquid is completed. There is no limit to the timing of The amount of the processing liquid discharged through the drain line 38 and the amount of DIW supplied to the tank 35 are not limited. extent increases. As an example, about 75% to 85% of the amount of the processing liquid in the tank 35 immediately before the discharging of the processing liquid (S4) and the supply of DIW (S5) is discharged through the drain line 38. Then, DIW can be supplied to the tank 35 in the same amount as the discharge amount of the processing liquid.

The amount of the treatment liquid discharged and the amount of DIW supplied may be predetermined amounts, but the amount of the treatment liquid discharged and the amount of DIW supplied may be determined according to the measurement result of the concentration sensor 46 in the treatment liquid supply system 22. may be determined. For example, the control unit 18 may acquire the difference between the concentration of the treatment liquid derived from the measurement result of the concentration sensor 46 after circulation (S2) of the treatment liquid and the target concentration. The control unit 18 may determine the discharge amount of the processing liquid from the processing liquid supply system 22 and the supply amount of the DIW to the tank 35 based on the difference between the concentration of the processing liquid and the target concentration. The control unit 18 controls the drain adjustment unit and the supply adjustment unit based on the result of the determination.

Further, the control unit 18 may acquire the concentration difference of the treatment liquid (hereinafter also referred to as "circulation concentration difference") derived from the measurement result of the concentration sensor 46 of the circulation line 36 before and after the circulation of the treatment liquid (S2). . If the concentration of the treatment liquid after the circulation of the treatment liquid (S2) deviates from the target concentration, the control unit 18 adjusts the concentration based on the condition of the circulation concentration difference, the concentration of the treatment liquid after circulation, and the target concentration. , the amount of processing liquid drained and the amount of DIW supplied to the tank 35 may be determined. The concentration of the processing liquid after circulation here is derived from the measurement result of the concentration sensor 46 .

After the discharge of the processing liquid and the supply of DIW to the tank 35, the circulation of the processing liquid (S2) and the determination of whether or not the concentration of the processing liquid has reached the target concentration (S3) are performed again. will be Then, when it is determined that the concentration of the processing liquid has reached the target concentration, the processing liquid preparation process is terminated, and when it is determined that the concentration of the processing liquid has not reached the target concentration, the processing liquid is Drainage (S4) and supply of DIW (S5) are again performed.

In this manner, the control unit 18 controls the drain adjustment unit, the supply adjustment unit, and the circulation pump 42, and discharges the processing liquid from the processing liquid supply system 22 and the DIW to the tank 35 until the concentration of the processing liquid reaches the target concentration. and circulation of the processing liquid in the processing liquid supply system 22 are repeated. In particular, the control unit 18 controls the circulation pump 42, the drain adjustment unit, and the supply adjustment unit after supplying the processing liquid having a concentration higher than the target concentration to the tank 35, so that the processing liquid in the tank 35 and the circulation line 36 is Circulation, discharge of processing liquid, and supply of DIW to the tank 35 are performed. After discharging the processing liquid from the processing liquid supply system 22 and supplying DIW to the tank 35 , the control unit 18 controls the circulation pump 42 to supply a certain amount of the processing liquid in at least the tank 35 and the circulation line 36 . circulate. Then, the control unit 18 controls the drain adjusting unit, the supply adjusting unit, and the circulation pump 42 until the measurement result of the concentration sensor 46 after a certain amount of the processing liquid circulates reaches the target concentration, thereby discharging the processing liquid, DIW. to the tank 35 and circulation of a certain amount of the processing liquid are repeated. As a result, the concentration imbalance between the processing liquid in the tank 35 whose concentration is changed by discharging the processing liquid from the processing liquid supply system 22 and supplying DIW to the tank 35 and the remaining processing liquid is eliminated. Thus, the concentration of the processing liquid in the tank 35 can be made uniform while approaching the target concentration.

As described above, according to this embodiment, the concentration of the processing liquid in the tank 35 can be adjusted while the concentration of the processing liquid in the entire processing liquid supply system 22 is made uniform. It is possible to appropriately manage the concentration of the processing liquid. Further, according to the present embodiment, even if the substrate processing system 1 (particularly, the processing liquid supply system 22) has a complicated channel configuration, or if there are individual differences in the constituent elements of the substrate processing system 1, desired Concentration processing liquid can be prepared with high accuracy.

In particular, after the concentration of the processing liquid in the entire processing liquid supply system 22 including the residual processing liquid has been homogenized, the concentration of the processing liquid is measured by the concentration sensor 46, and the necessity of discharging the processing liquid and supplying DIW is determined. is determined. By adjusting the concentration of the processing liquid in the tank 35 while considering the residual processing liquid in this manner, the processing liquid in the processing liquid supply system 22 can be quickly adjusted to a desired concentration (in this embodiment, an ultra-low concentration). be able to.

Conventionally, for example, the processing liquid in the tank is adjusted to the desired concentration without circulating the processing liquid, and then the processing liquid is circulated. In this case, the treatment liquid in the tank is repeatedly adjusted. On the other hand, according to the substrate processing system 1 and the processing liquid preparation method of the present embodiment, unintended fluctuations in the concentration of the processing liquid caused by such residual processing liquid do not occur. can be adjusted.

Further, according to the present embodiment, the concentration of the processing liquid in the tank 35 is gradually diluted after the processing liquid having a concentration higher than the target concentration is stored in the tank 35 . By increasing the concentration of the processing liquid stored in the tank 35 at the beginning of the process for adjusting the processing liquid concentration in this way, the degree of substantial influence of the residual processing liquid on the concentration of the processing liquid in the tank 35 can be reduced. can do. As a result, the concentration of the processing liquid in the processing liquid supply system 22 can be stably adjusted to the target concentration, and even if the target concentration is a low concentration (especially an ultra-low concentration of 3 ppm or less), the processing liquid of a desired concentration can be obtained. It can be prepared with high precision and stability.

[Second embodiment]
In this embodiment, the same or similar elements as those of the above-described first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

A plurality of processing liquid supply systems 22 may be provided. In this case, a switching unit for switching the connection state between each of the plurality of processing liquid supply systems 22 and the substrate processing system 21 may be provided. It is preferable that the control unit 18 controls the switching unit to switch the processing liquid supply system 22 that supplies the processing liquid to the substrate processing system 21 .

FIG. 5 is a diagram showing a schematic configuration example of the substrate processing system 21, the processing liquid supply system 22, and the processing liquid adjustment system 23 of the substrate processing system 1 according to the second embodiment.

A substrate processing system 1 shown in FIG. Prepare. Each processing liquid supply system 22 is connected to the substrate processing system 21 and to the processing liquid adjustment system 23 .

In the present embodiment, instead of the on-off valve 55d (see FIG. 3) provided downstream of the confluence point of the sub-supply line 72 in the main replenishment line 71 of the processing liquid adjustment system 23 in the above-described first embodiment, , a three-way valve or the like is provided. The main supply line 71 is connected to the supply switching device 76, and the first supply line 71a and the second supply line 71b are connected. The first supply line 71a is connected to the tank 35 of the first processing liquid supply system 22a, and the second supply line 71b is connected to the tank 35 of the second processing liquid supply system 22b. The supply switching device 76 switches connection and disconnection of the first supply line 71a and the second supply line 71b to the main supply line 71 on the upstream side under the control of the control unit 18 .

The main branch line 37 is connected to the circulation line 36 of the first processing liquid supply system 22a via the supply switching section 74 and the first branch line 37a, and is connected to the second processing line 36 via the supply switching section 74 and the second branch line 37b. It is connected to the circulation line 36 of the liquid supply system 22b. The supply switching unit 74 switches connection and disconnection of the first branch line 37 a and the second branch line 37 b to the main branch line 37 under the control of the control unit 18 .

The main return line 41 is connected to the tank 35 of the first processing liquid supply system 22a via the return switching section 75 and the first return line 41a, and is connected to the tank 35 of the first processing liquid supply system 22a via the return switching section 75 and the second return line 41b. It is connected to the tank 35 of the supply system 22b. The return switching unit 75 switches connection and disconnection of the first return line 41 a and the second return line 41 b to the main return line 41 under the control of the control unit 18 .

According to the substrate processing system 1 shown in FIG. 5, one of the first processing liquid supply system 22a and the second processing liquid supply system 22b is selectively used to process the wafer W in the substrate processing system 21. or prepare a treatment liquid.

For example, while the processing liquid is supplied from the first processing liquid supply system 22a to the substrate processing system 21 to process the wafer W in each processing unit 16, the processing liquid is prepared in the second processing liquid supply system 22b (see FIG. 4). ) can be done. In this case, the supply switching unit 74 connects the first branch line 37a to the main branch line 37, the return switching unit 75 connects the first return line 41a to the main return line 41, and the supply switching unit 76 connects the main supply line 71. is connected to the second supply line 71b. Similarly, while the processing liquid is supplied from the second processing liquid supply system 22b to the substrate processing system 21 to process the wafer W in each processing unit 16, the processing liquid is prepared in the first processing liquid supply system 22a. can also be done.

As described above, in the substrate processing system 1 of the present embodiment, the first processing liquid supply system 22 a and the second processing liquid supply system 22 b are provided so as to be connectable to the common processing liquid adjustment system 23 . A combination of the first processing liquid supply system 22a, the second processing liquid supply system 22b, and the processing liquid adjustment system 23 constitutes one circulation cabinet 24. As shown in FIG.

As described above, according to the substrate processing system 1 of the present embodiment, it is possible to selectively use the first processing liquid supply system 22a and the second processing liquid supply system 22b to perform substrate processing and prepare a processing liquid having a desired concentration. can. Therefore, it is possible to alternately use the first processing liquid supply system 22a and the second processing liquid supply system 22b as the processing liquid supply system 22 used for substrate processing and processing liquid preparation. In this case, the processing of the entire system can be efficiently performed. In particular, the processing time of the entire system can be shortened by simultaneously performing substrate processing and preparation of the processing liquid having a desired concentration in the first processing liquid supply system 22a and the second processing liquid supply system 22b.

[Third embodiment]
In this embodiment, the same or similar elements as those in the above-described first and second embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted.

A plurality of treatment liquid adjustment systems 23 may be provided. In this case, at least one of the first liquid, the second liquid, and the processing liquid may be supplied from each of the plurality of processing liquid adjustment systems 23 to the plurality of processing liquid supply systems 22 .

FIG. 6 is a diagram showing a schematic configuration example of the substrate processing system 21, the processing liquid supply system 22, and the processing liquid adjustment system 23 of the substrate processing system 1 according to the third embodiment.

The substrate processing system 1 shown in FIG. 6 includes a plurality of circulation cabinets 24 (specifically, a first circulation cabinet 24a and a second circulation cabinet 24b). Each circulation cabinet 24 includes a combination of a processing liquid supply system 22 and a processing liquid conditioning system 23 . That is, the first circulation cabinet 24a includes a first processing liquid supply system 22a and a first processing liquid adjustment system 23a which are connected to each other. The second circulation cabinet 24b includes a second processing liquid supply system 22b and a second processing liquid conditioning system 23b which are interconnected.

A first branch line 37 a is connected to the circulation line 36 of the first processing liquid supply system 22 a , and the first branch line 37 a is connected to the main branch line 37 via a supply switching section 74 . A second branch line 37 b is connected to the circulation line 36 of the second processing liquid supply system 22 b , and the second branch line 37 b is connected to the main branch line 37 via a supply switching section 74 . The supply switching unit 74 switches connection and disconnection of the first branch line 37 a and the second branch line 37 b to the main branch line 37 under the control of the control unit 18 .

A first return line 41 a is connected to the tank 35 of the first processing liquid supply system 22 a , and the first return line 41 a is connected to the main return line 41 via the return switching section 75 . A second return line 41 b is connected to the tank 35 of the second processing liquid supply system 22 b , and the second return line 41 b is connected to the main return line 41 via the return switching section 75 . The return switching unit 75 switches connection and disconnection of the first return line 41 a and the second return line 41 b to the main return line 41 under the control of the control unit 18 .

According to the substrate processing system 1 shown in FIG. 6, one of the first circulation cabinet 24a and the second circulation cabinet 24b is selectively used to process the wafers W in the substrate processing system 21 or to process the wafers W in the substrate processing system 21. Liquid preparation can be performed. For example, while the wafer W is processed by connecting the first circulation cabinet 24a (especially the first processing liquid supply system 22a) to the substrate processing system 21, the processing liquid is prepared in the second circulation cabinet 24b (see FIG. 4). It can be carried out. In this case, the supply switching unit 74 connects the first branch line 37 a to the main branch line 37 , and the return switching unit 75 connects the first return line 41 a to the main return line 41 . Similarly, while the second circulation cabinet 24b (especially the second processing liquid supply system 22b) is connected to the substrate processing system 21 to process the wafer W, the processing liquid is prepared in the first circulation cabinet 24a. can also

As described above, according to the present embodiment, the first circulation cabinet 24a and the second circulation cabinet 24b can be selectively used for substrate processing and preparation of a processing liquid having a desired concentration. Therefore, it is possible to alternately use the first circulation cabinet 24a and the second circulation cabinet 24b as the circulation cabinet 24 used for substrate processing and processing liquid preparation, respectively. In this case, the processing of the entire system can be efficiently performed. In particular, it is possible to shorten the processing time of the entire system by simultaneously performing substrate processing and preparation of processing solutions of desired concentrations in the first circulation cabinet 24a and the second circulation cabinet 24b.

[Modification]
In each of the embodiments described above, a second liquid (DIW) is supplied to the tank 35 to dilute the concentration of the processing liquid when the concentration of the processing liquid does not reach the target concentration (i.e., ultra-low concentration). (See S5 in FIG. 4). In this case, instead of the second liquid (DIW), the processing liquid (mixed liquid of the first liquid and the second liquid) may be supplied from the processing liquid adjustment system 23 to the tank 35 . However, in order to reduce the concentration of the processing liquid in the tank 35 and adjust it to the target concentration, the processing liquid having a concentration lower than the target concentration is supplied from the processing liquid adjustment system 23 to the tank 35 .

Further, when the concentration of the processing liquid in the tank 35 is lower than the target concentration, the first liquid (ammonium hydroxide) may be supplied from the processing liquid adjustment system 23 to the tank 35, or the processing liquid may may be supplied. When the processing liquid is supplied, the processing liquid having a higher concentration than the target concentration is supplied from the processing liquid adjustment system 23 to the tank 35 in order to adjust the concentration of the processing liquid in the tank 35 to the target concentration.

In any case, the control unit 18 continues to discharge the processing liquid and supply at least one of the first liquid, the second liquid, and the processing liquid to the tank 35 until the measurement result of the concentration sensor reaches the target concentration. repeat.

It should be noted that the embodiments disclosed in this specification are merely illustrative in all respects and should not be construed as limiting. The above-described embodiments can be omitted, substituted and modified in various ways without departing from the scope and spirit of the appended claims. For example, the above-described embodiments and modifications may be combined, and embodiments other than those described above may be combined with the above-described embodiments or modifications.

Also, the technical category that embodies the above technical idea is not limited. For example, the substrate processing system described above may be applied to other apparatuses. Moreover, the above-described technical idea may be embodied by a computer program for causing a computer to execute one or more procedures (steps) included in the above-described treatment liquid preparation method. Also, the above technical idea may be embodied by a computer-readable non-transitory recording medium in which such a computer program is recorded.

Claims (10)

a substrate processing system for processing a substrate using a processing liquid containing a first liquid and a second liquid;
a processing liquid supply system that supplies the processing liquid to the substrate processing system;
a processing liquid adjustment system that supplies at least one of the first liquid, the second liquid, and the processing liquid to the processing liquid supply system;
a control unit;
The processing liquid supply system is
a tank that is connected to the processing liquid adjustment system and stores the processing liquid; a circulation line that is connected to the tank and through which the processing liquid that exits the tank and returns to the tank flows;
a branch line connected to the circulation line and the substrate processing system;
a circulator for flowing the treatment liquid in the circulation line;
a drain line through which the processing liquid discharged from at least one of the tank and the circulation line flows;
a drain adjustment unit that adjusts discharge of the processing liquid through the drain line;
a concentration sensor that measures the concentration of the treatment liquid in at least one of the tank, the circulation line, a concentration measurement line connected to the tank, and a concentration measurement line connected to the circulation line. ,
The treatment liquid adjustment system has a supply adjustment unit that adjusts supply of at least one of the first liquid, the second liquid, and the treatment liquid to the tank,
The controller controls the circulator to circulate a certain amount of the processing liquid in the tank and the circulation line, and then controls the drain adjustment section to control the processing liquid based on the measurement result of the concentration sensor. and controlling the supply adjustment unit to adjust the supply of at least one of the first liquid, the second liquid and the processing liquid to the tank ;
When the processing liquid is discharged through the drain line based on the measurement result of the concentration sensor, the control unit is arranged to discharge a part of the processing liquid in the processing liquid supply system. A substrate processing system that controls the drain adjustment unit . The control unit controls the drain adjustment unit and the supply adjustment unit to discharge the treatment liquid and the first liquid, the second liquid, and the 2. The substrate processing system of claim 1, wherein the supply of at least one of the processing liquids to the tank is repeated. The control unit
After discharging the processing liquid and supplying at least one of the first liquid, the second liquid and the processing liquid to the tank, the circulator is controlled to control the tank and the circulation. circulating an amount of processing liquid in the line;
The drain adjustment unit, the supply adjustment unit, and the circulator are controlled until the measurement result of the concentration sensor after the certain amount of the treatment liquid circulates reaches the target concentration, and the treatment liquid is discharged. 3. The substrate processing system according to claim 2, wherein the supply of at least one of the first liquid, the second liquid and the processing liquid to the tank, and the circulation of the certain amount of the processing liquid are repeated. Based on the difference between the concentration of the treatment liquid derived from the measurement result of the concentration sensor and the target concentration, the control unit controls the discharge amount of the treatment liquid, the first liquid, the second liquid, and the 4. The substrate processing system according to claim 2, wherein the supply amount of at least one of the processing liquids to the tank is determined, and the drain adjustment unit and the supply adjustment unit are controlled based on the result of the determination. After controlling the supply adjustment unit to supply the processing liquid having a concentration higher than the target concentration to the tank, the control unit controls the circulator, the drain adjustment unit, and the supply adjustment unit, Circulating the processing liquid in the tank and the circulation line, discharging the processing liquid, and supplying at least one of the first liquid, the second liquid, and the processing liquid to the tank. 5. The substrate processing system according to any one of 2 to 4. a filter provided downstream of the circulator in the circulation line;
a liquid supply adjustment unit provided downstream of the filter in the circulation line and adjusting supply of the processing liquid from the circulation line to the substrate processing system;
the concentration measurement line is connected to a portion of the circulation line between the filter and the liquid supply adjustment unit;
6. The substrate processing system according to claim 1, wherein the concentration sensor measures the concentration of the processing liquid flowing through the concentration measurement line. A plurality of the processing liquid supply systems are provided,
a switching unit for switching a connection state between each of the plurality of processing liquid supply systems and the substrate processing system;
7. The substrate processing system according to claim 1, wherein the control unit controls a switching unit to switch the processing liquid supply system that supplies the processing liquid to the substrate processing system. A plurality of the treatment liquid adjustment systems are provided,
8. The plurality of processing liquid supply systems according to claim 7, wherein at least one of the first liquid, the second liquid and the processing liquid is supplied from each of the plurality of processing liquid adjustment systems. substrate processing system. The substrate processing system is
a processing unit connected to the branch line and supplying the processing liquid from the branch line to the substrate;
9. The substrate processing system according to claim 1, further comprising a return line that guides the processing liquid discharged from the processing unit to the tank. A substrate processing system for processing a substrate using a processing liquid containing a first liquid and a second liquid, and a processing liquid supply system for supplying the processing liquid to the substrate processing system, wherein the processing liquid is stored. a circulation line connected to the tank through which the processing liquid flows out from the tank and returns to the tank; a circulator through which the processing liquid flows in the circulation line; and at least one of the tank and the circulation line. a drain line through which the processing liquid discharged from the unit flows, a drain adjustment unit that adjusts the discharge of the processing liquid, the tank, the circulation line, a concentration measurement line connected to the tank, and the circulation line connected to the a processing liquid supply system having a concentration sensor for measuring the concentration of the processing liquid in at least one of the concentration measurement lines; and at least one of the first liquid, the second liquid, and the processing liquid. to the processing liquid supply system, the supply adjusting unit adjusting the supply of at least one of the first liquid, the second liquid and the processing liquid to the tank A processing liquid preparation method performed in a substrate processing system comprising:
circulating an amount of processing liquid in the tank and the circulation line by the circulator;
measuring the concentration of the treatment liquid with the concentration sensor after circulating the certain amount of the treatment liquid;
controlling the drain adjustment unit to adjust discharge of the treatment liquid based on the measurement result of the concentration sensor;
controlling the supply adjusting unit to adjust the supply of at least one of the first liquid, the second liquid and the processing liquid to the tank based on the measurement result of the concentration sensor; , including
When the processing liquid is discharged through the drain line based on the measurement result of the concentration sensor, the drain adjustment unit is adjusted so that a part of the processing liquid in the processing liquid supply system is discharged. A method of preparing a treatment liquid that controls .

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