JP7695038B2 - SUBSTRATE PROCESSING APPARATUS AND SUBSTRATE PROCESSING METHOD - Google Patents

Description

This disclosure relates to a substrate processing apparatus and a substrate processing method.

The cleaning and drying unit described in Patent Document 1 has a cleaning tank that stores a rinsing liquid (e.g., pure water), a drying tank located above the cleaning tank, a substrate holder that holds substrates, and a lifting mechanism that raises and lowers the substrate holder. The substrate holder holds multiple substrates in an upright position and arranged horizontally. The lifting mechanism raises and lowers the substrate holder between the cleaning tank and the drying tank. The multiple substrates are immersed in a rinsing liquid stored in the cleaning tank, and then pulled up from the surface of the rinsing liquid and dried in the drying tank.

Patent No. 6144236

This disclosure provides technology that can prevent particles from adhering to substrates regardless of the number of substrates being processed.

A substrate processing apparatus according to one aspect of the present disclosure includes a processing tank for storing a processing liquid in which a substrate is immersed, a drying tank disposed above the processing tank for drying the substrate, a gas supply unit for supplying a mixed gas containing an inert gas and vapor of an organic solvent to the drying tank, and a control unit for controlling the gas supply unit, wherein the control unit changes a supply flow rate of the inert gas and a supply flow rate of the organic solvent in accordance with a state of the substrate while maintaining a constant vapor concentration of the organic solvent in the mixed gas supplied to the drying tank, the state of the substrate including the number of substrates, the control unit has a storage medium for storing information regarding a correlation between the number of substrates, the supply flow rate of the inert gas, and the supply flow rate of the organic solvent, and the control unit uses the information to calculate the supply flow rate of the inert gas and the supply flow rate of the organic solvent according to the number of substrates to be processed .

According to the present disclosure, it is possible to prevent particles from adhering to substrates regardless of the number of substrates processed.

FIG. 1 is a diagram showing an example of a substrate processing apparatus. FIG. 2 is a diagram showing an example of a substrate processing apparatus. FIG. 3 is a cross-sectional view showing an example of a substrate holder. FIG. 4 is a diagram illustrating an example of the table. FIG. 5 is a diagram illustrating an example of the table. FIG. 6 is a diagram illustrating an example of the table. FIG. 7 is a diagram illustrating an example of the table. FIG. 8 is a diagram illustrating an example of the table. FIG. 9 is a flow chart showing an example of a substrate processing method. FIG. 10 is a diagram illustrating an example of a substrate processing method. FIG. 11 is a diagram illustrating an example of a substrate processing method. FIG. 12 is a diagram illustrating an example of a substrate processing method. FIG. 13 is a diagram illustrating an example of a substrate processing method. FIG. 14 is a diagram illustrating another example of a substrate processing method. FIG. 15 is a diagram for explaining why particles adhere to a substrate. FIG. 16 is a diagram for explaining why particles adhere to a substrate. FIG. 17 is a diagram showing the measurement results of the number of particles adhering to the substrate.

Hereinafter, non-limiting exemplary embodiments of the present disclosure will be described with reference to the attached drawings. In all the attached drawings, the same or corresponding members or parts are denoted by the same or corresponding reference numerals, and duplicate descriptions will be omitted.

[Substrate Processing Apparatus]
1 to 8, an example of a substrate processing apparatus 1 will be described. The substrate processing apparatus 1 supplies a processing liquid L to a substrate W, and then dries the substrate W. The substrate processing apparatus 1 includes a processing container 10, a substrate holder 20, a gas supply unit 30, a gas exhaust unit 40, and a control unit 90.

The processing vessel 10 has a processing tank 11 that stores processing liquid L in which the substrate W is immersed. The processing liquid L is, for example, pure water such as DIW. The processing tank 11 has, for example, an inner tank 111 that stores the processing liquid L, an outer tank 112 that collects the processing liquid L that overflows from the inner tank 111, and a seal tank 113 that surrounds the upper end of the outer tank 112. A nozzle 51 that supplies processing liquid L to the inner tank 111 is provided inside the inner tank 111. A discharge port 52 that discharges the processing liquid L stored inside the inner tank 111 is provided on the bottom wall of the inner tank 111.

The processing vessel 10 has a drying chamber 12 for drying the substrate W. The drying chamber 12 is disposed above the processing chamber 11. The drying chamber 12 includes, for example, a cylindrical side wall 121. The cylindrical side wall 121 is open upward and has an opening 122 for loading and unloading the substrate W at its upper end. The drying chamber 12 further has a lid 123 for opening and closing the opening 122. The lid 123 is dome-shaped with an upward convex shape, and is raised and lowered by an opening and closing mechanism 53.

The processing vessel 10 has a casing 13 between the processing tank 11 and the drying tank 12. A shutter 14 is movably arranged inside the casing 13. The shutter 14 is moved between a communication position that connects the processing tank 11 and the drying tank 12 as shown in FIG. 1, and a blocking position that blocks the processing tank 11 and the drying tank 12 as shown in FIG. 2.

The substrate processing apparatus 1 further includes an opening/closing mechanism 54 that moves the shutter 14 between the communication position and the blocking position. The opening/closing mechanism 54 moves the shutter 14 in the horizontal direction. The opening/closing mechanism 54 may also move the shutter 14 in the vertical direction. The shutter 14 is disposed horizontally and holds a frame-shaped seal member 15 on its upper surface.

As shown in FIG. 3, for example, the substrate holder 20 holds each of a plurality of substrates W arranged at intervals in the horizontal direction upright. The substrate holder 20 can also hold only one substrate W. The substrate holder 20 has a plurality of arms 21 (for example, four) extending in the horizontal direction, for example. Each of the arms 21 includes grooves 211 formed at equal pitches in the extension direction. The peripheral edge of the substrate W is inserted into the grooves 211. The arms 21 hold the peripheral edge of each substrate W at multiple points.

The substrate holder 20 has a vertical back plate 22 that supports multiple arms 21 in a cantilevered manner, and a lifting rod 23 (see Figures 1 and 2) that extends directly upward from the back plate 22. The lifting rod 23 is inserted into a through hole in the lid 123, and a sealing mechanism is provided in the through hole. A lifting mechanism 55 is connected to the upper end of the lifting rod 23. The lifting mechanism 55 raises and lowers the substrate holder 20.

The gas supply unit 30 supplies gas into the processing vessel 10. The gas to be supplied is, for example, an inert gas G1, or a mixed gas of the inert gas G1 and an organic solvent vapor G2. The inert gas is, for example, nitrogen (N ₂ ) gas. The organic solvent is, for example, IPA (isopropyl alcohol). The gas to be supplied may be preheated from the viewpoint of accelerating drying of the substrate W.

The gas supply unit 30 includes a nozzle 31. The nozzle 31 is provided inside the processing vessel 10 and supplies gas to the inside of the processing vessel 10. A supply line 32 is connected to the nozzle 31. The supply line 32 has a common line 321 and a plurality of individual lines 322-323.

The common line 321 connects the junction of the multiple individual lines 322-323 to the nozzle 31. A heater 33 for heating the gas to be supplied may be provided midway along the common line 321.

The individual line 322 supplies an inert gas G1 to the nozzle 31. The individual line 323 supplies an organic solvent vapor G2 to the nozzle 31. An opening/closing valve 34 and a flow rate controller 35 are provided midway along each of the individual lines 322 and 323.

The gas exhaust unit 40 exhausts gas from the inside of the processing vessel 10 to the outside. The gas exhaust unit 40 includes an exhaust line 41 extending from, for example, the drying tank 12. An opening/closing valve 42 and a flow rate controller 43 are provided in the exhaust line 41.

The control unit 90 controls each part of the substrate processing apparatus 1. The control unit 90 is, for example, a computer, and includes a CPU (Central Processing Unit) 91 and a storage medium 92 such as a memory. The storage medium 92 stores programs that control various processes executed in the substrate processing apparatus 1. The control unit 90 controls the operation of the substrate processing apparatus 1 by having the CPU 91 execute the programs stored in the storage medium 92.

The CPU 91 corrects the supply flow rate of the inert gas and the supply flow rate of the organic solvent according to the number of substrates W to be processed.

The storage medium 92 stores various information that the CPU 91 uses to calculate the supply flow rate of the inert gas and the supply flow rate of the organic solvent.

The various information may include a table T1 in which the vapor concentration of the organic solvent in the mixed gas supplied to the drying chamber 12 (hereinafter referred to as the "vapor concentration of the organic solvent") is associated with the reference supply flow rate of the inert gas and the reference supply flow rate of the organic solvent when the number of substrates W is a reference number. The reference number may be, for example, the maximum number of substrates W that the substrate holder 20 can hold. For example, as shown in FIG. 4, in table T1, the reference number is 100 substrates, and the reference supply flow rate of the inert gas and the reference supply flow rate of the organic solvent when the vapor concentration of the organic solvent is D1 [vol %] are X1 [L/min] and Y1 "ml/sec", respectively.

The various information may include table T2 in which the vapor concentration of the organic solvent, the number of substrates W, and the supply flow rate ratio of the inert gas are associated. If the vapor concentration of the organic solvent is not changed from the reference concentration, table T2 may not include the concentration of the organic solvent. The supply rate of the inert gas is a value expressed as a percentage relative to the reference supply flow rate. For example, as shown in FIG. 5, in table T2, the supply flow rate ratio of the inert gas is 44% when the vapor concentration of the organic solvent is D1 [vol %] and the number of substrates W is 1 to 10.

The various information may include table T3 in which the vapor concentration of the organic solvent, the number of substrates W, and the supply flow rate ratio of the organic solvent are associated. If the vapor concentration of the organic solvent is not changed from the reference concentration, table T3 may not include the concentration of the organic solvent. The supply flow rate ratio of the organic solvent is a value expressed as a percentage relative to the reference supply flow rate. For example, as shown in FIG. 6, in table T3, the supply flow rate ratio of the organic solvent is 44% when the vapor concentration of the organic solvent is D1 [vol %] and the number of substrates W is 1 to 10. It is sufficient to have only one of tables T2 and T3. Since the vapor concentration of the organic solvent is controlled to a constant value, once either the supply flow rate ratio of the inert gas or the supply flow rate ratio of the organic solvent is determined, the other is automatically determined.

The various information may include a table T4 in which the organic solvent vapor concentration, the number of substrates W, and the supply flow rate of the inert gas are associated with each other. The supply flow rate of the inert gas is fixed, for example, regardless of the organic solvent vapor concentration, and is changed only according to the number of substrates W. The supply flow rate of the organic solvent vapor is automatically determined from the organic solvent vapor concentration and the supply flow rate of the inert gas. When the organic solvent vapor concentration is changed in a recipe or the like, the supply flow rate of the organic solvent vapor is corrected based on the changed vapor concentration. Note that, if the organic solvent vapor concentration is not changed from the reference concentration, table T4 does not need to include the organic solvent concentration. For example, as shown in FIG. 7, in table T4, the organic solvent vapor concentration is D1 [vol %], and the supply flow rate of the inert gas is P1 [L/min] when the number of substrates W is 1 to 10.

The various information may include a table T5 in which the number of substrates W, the vapor concentration of the organic solvent, and the supply flow rate of the organic solvent are associated with each other. For example, as shown in FIG. 8, in table T5, when the number of substrates W is 1 to 10 and the vapor concentration of the organic solvent is D1, D2, D3 [vol %], the supply flow rates of the organic solvent are Q11, Q21, and Q31 [ml/sec], respectively. In table T5, the magnitude relationship between D1, D2, and D3 is D1<D2<D3, and the magnitude relationship between Q11, Q21, and Q31 is Q11<Q21<Q31. The magnitude relationships between Q12 to Q20, Q22 to Q30, and Q31 to Q40 are the same as those between Q11, Q21, and Q31.

[Substrate Processing Method]
9 to 14, an example of a substrate processing method carried out in the substrate processing apparatus 1 of the embodiment will be described. The substrate processing method is carried out by a control unit 90 controlling each unit of the substrate processing apparatus 1.

In step S11, the control unit 90 calculates the supply flow rate of the inert gas and the supply flow rate of the organic solvent according to the number of substrates W to be processed.

For example, the control unit 90 acquires the vapor concentration of the organic solvent and the number of substrates W to be processed. The vapor concentration of the organic solvent is, for example, a value set in a recipe. The number of substrates W to be processed is, for example, a value acquired by measuring the number of substrates W stored in a transport container such as a FOUP (Front Opening Unified Pod) placed on a load port before the substrates W are loaded into the processing container 10. The control unit 90 also calculates the supply flow rate of the inert gas based on the acquired vapor concentration of the organic solvent, the acquired number of substrates W to be processed, the table T1 stored in the storage medium 92, and the table T2 stored in the storage medium 92. The control unit 90 also calculates the supply flow rate of the organic solvent based on the acquired vapor concentration of the organic solvent, the acquired number of substrates W to be processed, the table T1 stored in the storage medium 92, and the table T3 stored in the storage medium 92. As an example, consider a case where the vapor concentration of the organic solvent is D1 and the number of substrates W is 1 to 10. In this case, the supply flow rate of the inert gas is obtained by multiplying the supply flow rate X1 of the inert gas obtained by referring to Table T1 by the supply flow rate ratio of the inert gas of 44% obtained by referring to Table T2 and dividing the result by 100. That is, the supply flow rate of the inert gas is calculated by (X1 x 44)/100. The supply flow rate of the organic solvent is also obtained by multiplying the supply flow rate Y1 of the organic solvent obtained by referring to Table T1 by the supply flow rate ratio of the organic solvent of 44% obtained by referring to Table T3 and dividing the result by 100. That is, the supply flow rate of the organic solvent is calculated by (Y1 x 44)/100.

For example, when calculating the supply flow rate of the inert gas and the supply flow rate of the organic solvent, the control unit 90 may refer to table T4 stored in the storage medium 92 instead of referring to table T1, table T2, and table T3. In this case, the control unit 90 calculates the supply flow rate of the inert gas and the supply flow rate of the organic solvent based on the acquired vapor concentration of the organic solvent, the acquired number of substrates W to be processed, and table T4 stored in the storage medium 92. As an example, consider a case where the vapor concentration of the organic solvent is D1 and the number of substrates W is 1 to 10. In this case, the supply flow rate of the organic solvent is obtained by a known calculation based on the supply flow rate P1 of the inert gas obtained by referring to table T4 and the vapor concentration D1 of the organic solvent. In addition, the supply flow rate of the organic solvent may be calculated for each number of substrates W and vapor concentration of the organic solvent by a similar calculation, and table T5 in which the number of substrates W, the vapor concentration of the organic solvent, and the supply flow rate of the organic solvent are associated with each other may be generated and stored in the storage medium 92.

In step S12, the control unit 90 controls the operation of the substrate processing apparatus 1 so as to perform a drying process on the substrate W to be processed in the substrate processing apparatus 1.

First, as shown in FIG. 10(a), before the substrate W is loaded into the processing vessel 10, the lid 123 is moved to the closed position. At this time, heated inert gas G1 is supplied from the nozzle 31 into the inside of the drying chamber 12, and the gas inside the drying chamber 12 is exhausted from the exhaust line 41 to the outside, thereby adjusting the temperature inside the drying chamber 12. In addition, processing liquid L is supplied from the nozzle 51 into the inside of the processing chamber 11.

Next, as shown in FIG. 10(b), the opening/closing mechanism 53 moves the lid 123 from the closed position to the open position. Next, the substrate holder 20 (see FIG. 1 and FIG. 2; not shown in FIG. 10 to FIG. 14) receives the substrates W from the transport device (not shown) above the processing vessel 10. Note that the substrate holder 20 can hold only one substrate W, as described above. Next, the lifting mechanism 55 (see FIG. 1 and FIG. 2; not shown in FIG. 10 to FIG. 14) lowers the substrate holder 20. While the lifting mechanism 55 lowers the substrate holder 20, the shutter 14 is positioned in the communication position so as not to interfere with the substrate holder 20 and the substrate W. The lifting mechanism 55 lowers the substrate holder 20 to immerse the substrates W in the processing liquid L. This allows the substrates W to be processed simultaneously. At this time, a small flow rate (e.g., 20 L/min) of inert gas G1 is supplied from the nozzle 31 to the inside of the drying tank 12, and the gas inside the drying tank 12 is exhausted to the outside from the exhaust line 41. In addition, the processing liquid L is supplied from the nozzle 51 to the inside of the processing tank 11.

Next, as shown in FIG. 10(c), the opening/closing mechanism 53 moves the lid 123 from the open position to the closed position, and the loading/unloading port 122 is closed by the lid 123. At this time, a large flow rate (e.g., 356 L/min) of inert gas G1 is supplied from the nozzle 31 to the inside of the drying tank 12, and the gas inside the drying tank 12 is exhausted to the outside from the exhaust line 41. In addition, the processing liquid L is supplied from the nozzle 51 to the inside of the processing tank 11.

11(a), the lifting mechanism 55 raises the substrate holder 20 to lift the substrates W from the processing liquid L stored inside the processing tank 11, and the substrate holder 20 is stopped in the internal space of the drying tank 12. At this time, a small flow rate (e.g., 30 L/min) of inert gas G1 is supplied from the nozzle 31 to the inside of the drying tank 12, and the gas inside the drying tank 12 is exhausted to the outside from the exhaust line 41, volatilizing the droplets adhering to the substrates W and drying the substrates W. Also, the processing liquid L is supplied from the nozzle 51 to the inside of the processing tank 11.

Next, as shown in FIG. 11(b), a mixed gas G3 of an inert gas G1 and an organic solvent vapor G2 is supplied from the nozzle 31 into the inside of the drying tank 12, and the gas inside the drying tank 12 is discharged from the exhaust line 41 to the outside. The organic solvent vapor G2 comes into contact with the front and back surfaces of each substrate W, condenses (dews) on the front and back surfaces of each substrate W, and the processing liquid L on the front and back surfaces of each substrate W is replaced by the condensed organic solvent. This can promote drying of the substrate W. At this time, a mixed gas of an inert gas and an organic solvent vapor is supplied into the inside of the drying tank 12 at the supply flow rate of the inert gas and the supply flow rate of the organic solvent calculated in step S11. In addition, the processing liquid L is supplied into the inside of the processing tank 11 from the nozzle 51.

Next, as shown in FIG. 11(c), the opening/closing mechanism 54 moves the shutter 14 from the communication position to the blocking position. At this time, the supply of the mixed gas G3 to the inside of the drying tank 12, the exhaust of the gas to the outside of the drying tank 12, and the supply of the processing liquid L to the inside of the processing tank 11 continue.

Next, as shown in FIG. 12(a), with the shutter 14 moved to the blocking position, the supply of mixed gas G3 into the drying tank 12, the exhaust of gas to the outside of the drying tank 12, and the supply of processing liquid L into the processing tank 11 are continued for a predetermined time. The predetermined time is determined, for example, by a recipe.

Next, as shown in FIG. 12(b), an inert gas is supplied from the nozzle 31 to the inside of the drying tank 12 at a first flow rate (e.g., 270 L/min), and the gas inside the drying tank 12 is discharged to the outside from the discharge line 41. In addition, the supply of the processing liquid L from the nozzle 51 to the inside of the processing tank 11 is stopped. This allows the amount of processing liquid L used to be reduced.

Next, as shown in FIG. 12(c), an inert gas is supplied from the nozzle 31 to the inside of the drying tank 12 at a second flow rate (e.g., 445 L/min) greater than the first flow rate, and the gas inside the drying tank 12 is discharged to the outside from the discharge line 41. In addition, the supply of the processing liquid L from the nozzle 51 to the inside of the processing tank 11 continues to be stopped. This allows the amount of processing liquid L used to be reduced.

Next, as shown in FIG. 13, the opening/closing mechanism 53 moves the lid 123 from the closed position to the open position to open the loading/unloading port 122. The lifting mechanism 55 raises the substrate holder 20 to unload the substrates W from the processing vessel 10. The substrate holder 20 then transfers the substrates W to a transport device (not shown) above the processing vessel 10. At this time, a small flow rate (e.g., 20 L/min) of inert gas G1 is supplied from the nozzle 31 to the inside of the drying vessel 12, and the gas inside the drying vessel 12 is exhausted from the exhaust line 41 to the outside. The supply of the processing liquid L from the nozzle 51 to the inside of the processing vessel 11 is continued to be stopped. This allows the amount of processing liquid L used to be reduced.

This completes the substrate processing method of this embodiment.

In the above embodiment, the inert gas G1 is supplied from the nozzle 31 to the inside of the drying tank 12 when the substrates W are lifted from the processing liquid L stored in the processing tank 11, but this is not limited to the above. For example, as shown in FIG. 14(a) and FIG. 14(b), the mixed gas G3 may be supplied from the nozzle 31 to the inside of the drying tank 12 after the substrates W are immersed in the processing liquid L and before the substrates W are lifted until the substrates are lifted. This allows a film of organic solvent to be formed on the liquid surface of the processing liquid L. As a result, the substrates W pass through the organic solvent film during lifting, and the processing liquid L on the front and back surfaces of the substrates W is replaced with the organic solvent, accelerating the drying of the substrates W.

In the above embodiment, the mixed gas of the inert gas G1 and the organic solvent vapor G2 is supplied from the nozzle 31 to the inside of the drying tank 12 at a constant flow rate, but this is not limited to this. For example, the flow rate of the mixed gas G3 of the inert gas G1 and the organic solvent vapor G2 supplied from the nozzle 31 to the inside of the drying tank 12 may be changed midway while maintaining the vapor concentration of the organic solvent constant. As an example, while maintaining the vapor concentration of the organic solvent constant, the mixed gas G3 may be first supplied at the same flow rate as the mixed gas flow rate in the above embodiment, and then the mixed gas G3 may be supplied at a flow rate greater than the mixed gas flow rate in the above embodiment. As another example, while maintaining the vapor concentration of the organic solvent constant, the mixed gas G3 may be first supplied at a flow rate greater than the mixed gas flow rate in the above embodiment, and then the mixed gas G3 may be supplied at the same flow rate as the mixed gas flow rate in the above embodiment. In this way, by adding the supply of mixed gas G3 at a flow rate greater than the flow rate of the mixed gas in the above embodiment, the organic solvent vapor G2 is more likely to reach the bottom end of each substrate W, facilitating the replacement of droplets of processing liquid L remaining at the bottom end of the substrate W by the organic solvent.

With reference to FIG. 15, the reason why particles adhere to the substrate W when a second number (e.g., three substrates) of substrates W, which is less than the first number, is dried while controlling the supply flow rate of the inert gas and the supply flow rate of the organic solvent to values for the first number (e.g., 50 to 80 substrates) will be described. In this case, the amount of vapor of the organic solvent becomes excessive inside the drying chamber 12. As a result, the vapor of the organic solvent condenses on the front and back surfaces of the substrate W, as well as on the inner wall surfaces of the drying chamber 12 and the surface of the substrate holder 20. Therefore, when an inert gas is supplied into the drying chamber 12 following the supply of the mixed gas, the inert gas causes the organic solvent OS condensed on the inner wall surfaces of the drying chamber 12 and the surface of the substrate holder 20 to float in a mist state. As a result, as shown by the dashed arrow in FIG. 15, the organic solvent OS floating in a mist state reattaches to the substrate W and becomes particles.

With reference to FIG. 16, the reason why particles adhere to the substrate W when a third number (e.g., 100 substrates) greater than the first number is dried while controlling the supply flow rate of the inert gas and the supply flow rate of the organic solvent to values for the first number (e.g., 50 to 80 substrates). In this case, as shown by the solid arrow in FIG. 16, the organic solvent vapor tends to flow into the wide space between the substrate W held at one end and the other end of the substrate holder 20 and the inner wall surface of the drying chamber 12. As a result, in the substrate W held at one end and the other end of the substrate holder 20, more organic solvent vapor condenses on the inner wall surface side of the drying chamber 12 than on the surface on the other substrate W side. Therefore, before the organic solvent vapor condenses on the surface on the other substrate W side, the temperature of the substrate W rises due to the condensation heat of the organic solvent OS condensed on the inner wall surface side of the drying chamber 12. Therefore, the condensation of the organic solvent vapor on the surface on the other substrate W side is insufficient. As a result, droplets of the processing liquid L remain on the lower end of the surface of the substrate W held at one end and the other end of the substrate holder 20 facing the other substrate W, and when the droplets evaporate, the residue in the droplets becomes particles.

In contrast, in the substrate processing apparatus 1 of the embodiment, the control unit 90 changes the supply flow rate of the inert gas and the supply flow rate of the organic solvent according to the number of substrates W while maintaining a constant vapor concentration of the organic solvent in the mixed gas supplied to the drying tank 12.

For example, when the number of substrates W is the second number, the control unit 90 maintains the organic solvent vapor concentration constant while reducing the supply flow rate of the inert gas and the supply flow rate of the organic solvent compared to when the number of substrates W is the first number. This prevents the amount of organic solvent vapor from becoming excessive inside the drying tank 12. This makes it possible to reduce the amount of organic solvent vapor that condenses on the inner wall surfaces of the drying tank 12, the surface of the substrate holder 20, and the like. As a result, adhesion of particles to the substrates W can be suppressed.

For example, when the number of substrates W is the third number, the control unit 90 maintains the organic solvent vapor concentration constant while increasing the supply flow rate of the inert gas and the supply flow rate of the organic solvent compared to when the number of substrates W is the first number. This makes it easier to supply organic solvent vapor between adjacent substrates W. Therefore, the difference in the amount of organic solvent vapor condensed between the surface of the substrate W held at one end and the other end of the substrate holder 20 facing another substrate W and the surface facing the inner wall of the drying tank 12 becomes smaller, and the organic solvent vapor is sufficiently condensed on both surfaces. As a result, adhesion of particles to the substrate W can be suppressed.

[Example]
In the substrate processing apparatus 1 of the embodiment, an example will be described in which a drying process was performed under the following four conditions A to D in which the number of substrates W, the supply flow rate of the inert gas, and the supply flow rate of the organic solvent were changed, and then the number of particles adhering to the substrates W was measured. In the example, IPA was used as the organic solvent, and nitrogen gas was used as the inert gas. In the example, in order to confirm reproducibility, an evaluation in which the drying process and the measurement of the number of particles were performed in sequence under each of the conditions A to D was performed three times.

Conditions A and B are conditions in which the supply flow rate of the inert gas and the supply flow rate of the organic solvent are fixed, in other words, the supply flow rate of the inert gas and the supply flow rate of the organic solvent are not changed according to the number of substrates W. Specifically, in condition A, the number of substrates W was set to 3, the supply flow rate of the inert gas was set to 79%, and the supply flow rate of the organic solvent was set to 79%. In condition B, the number of substrates W was set to 100, the supply flow rate of the inert gas was set to 79%, and the supply flow rate of the organic solvent was set to 79%.

Conditions C and D are conditions in which the supply flow rate of the inert gas and the supply flow rate of the organic solvent are biased according to the number of substrates W. Specifically, in condition C, the number of substrates W was set to 3, the supply flow rate of the inert gas was set to 44%, and the supply flow rate of the organic solvent was set to 44%. In condition D, the number of substrates W was set to 100, the supply flow rate of the inert gas was set to 100%, and the supply flow rate of the organic solvent was set to 100%.

In addition, under conditions A to D, the vapor concentration of the organic solvent supplied to the drying tank 12 is constant.

Figure 17 shows the results of measuring the number of particles adhering to a substrate W, and shows the results of measuring the number of particles of 40 nm or more adhering to one substrate W for each condition. In Figure 17, "one end," "center," and "other end" respectively show the results for substrates W located at one end, the center, and the other end of the substrate holder 20. Additionally, "first time," "second time," and "third time" respectively show the results of the first, second, and third times out of the three evaluations performed.

As shown in FIG. 17, under conditions C and D, the number of particles is small regardless of the position on the substrate W. Specifically, under condition C, the number of particles ranged from 0 to 10 in the evaluation performed three times. Under condition D, the number of particles ranged from 1 to 12 in the evaluation performed three times.

In contrast, it can be seen that the number of particles is greater under conditions A and B than under conditions C and D. Specifically, under condition A, the number of particles ranged from 9 to 70 in the evaluation performed three times. Under condition B, the number of particles ranged from 1 to 46 in the evaluation performed three times. Furthermore, under condition B, the number of particles was greater on the substrates W located at one end and the other end of the substrate holder 20 than on the substrate W located in the center of the substrate holder 20.

These results show that when the number of substrates W is small, the adhesion of particles to the substrates W can be suppressed by reducing the supply flow rate of the inert gas and the supply flow rate of the organic solvent while maintaining the vapor concentration of the organic solvent constant. On the other hand, when the number of substrates W is large, the adhesion of particles to the substrates W can be suppressed by increasing the supply flow rate of the inert gas and the supply flow rate of the organic solvent while maintaining the vapor concentration of the organic solvent constant. In other words, it was shown that the adhesion of particles to the substrates W can be suppressed by changing the supply flow rate of the inert gas and the supply flow rate of the organic solvent depending on the number of substrates W while maintaining the vapor concentration of the organic solvent constant.

The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. The above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

In the above embodiment, the case where the supply flow rate of the inert gas and the supply flow rate of the organic solvent are changed according to the number of substrates W while maintaining the vapor concentration of the organic solvent constant has been described, but the present disclosure is not limited thereto. In other words, the state of the substrates W is not limited to the number of substrates W. The supply flow rate of the inert gas and the supply flow rate of the organic solvent may be changed according to the arrangement pitch of the multiple substrates W held by the substrate holder 20 while maintaining the vapor concentration of the organic solvent constant. In this case, the narrower the arrangement pitch of the substrates W, the larger the supply flow rate of the inert gas and the supply flow rate of the organic solvent can be, thereby suppressing adhesion of particles to the substrates W. In addition, for example, the supply flow rate of the inert gas and the supply flow rate of the organic solvent may be changed according to both the number of substrates W and the arrangement pitch of the substrates W while maintaining the vapor concentration of the organic solvent constant.

Reference Signs List 1 Substrate processing apparatus 11 Processing tank 12 Drying tank 30 Gas supply unit 90 Control unit W Substrate

Claims (10)

a processing tank for storing a processing solution in which the substrate is immersed;
a drying tank disposed above the processing tank for drying the substrate;
a gas supply unit for supplying a mixed gas containing an inert gas and an organic solvent vapor to the drying tank;
A control unit that controls the gas supply unit;
having
the control unit changes a supply flow rate of the inert gas and a supply flow rate of the organic solvent in accordance with a state of the substrate while maintaining a constant vapor concentration of the organic solvent in the mixed gas supplied to the drying tank;
the state of the substrate includes the number of the substrates;
the control unit has a storage medium that stores information regarding a correlation between the number of the substrates, the supply flow rate of the inert gas, and the supply flow rate of the organic solvent;
the control unit uses the information to calculate a supply flow rate of the inert gas and a supply flow rate of the organic solvent according to the number of substrates to be processed.
Substrate processing equipment. the control unit increases the supply flow rate of the inert gas and the supply flow rate of the organic solvent as the number of substrates to be processed increases.
The substrate processing apparatus according to claim 1 . The control unit counts the number of substrates to be processed before the substrates are carried into the drying tank.
The substrate processing apparatus according to claim 1 . the control unit changes a supply flow rate of the organic solvent midway when the mixed gas is supplied to the drying tank.
The substrate processing apparatus according to claim 1 . the control unit supplies the mixed gas to the drying tank after the substrate is immersed in the treatment liquid and before the substrate is lifted up from the treatment liquid, and subsequently supplies the mixed gas to the drying tank when the substrate is lifted up from the treatment liquid.
The substrate processing apparatus according to claim 1 . Immersing the substrate in a processing solution stored in a processing tank;
drying the substrate by supplying a mixed gas containing an inert gas and an organic solvent vapor to a drying tank disposed above the processing tank;
having
drying the substrate includes changing a supply flow rate of the inert gas and a supply flow rate of the organic solvent in accordance with a state of the substrate while maintaining a constant vapor concentration of the organic solvent in the mixed gas supplied to the drying tank;
the state of the substrate includes the number of the substrates;
storing information regarding a correlation between the number of the substrates, the supply flow rate of the inert gas, and the supply flow rate of the organic solvent;
calculating a supply flow rate of the inert gas and a supply flow rate of the organic solvent according to the number of substrates to be processed using the information;
The substrate processing method comprises: drying the substrates includes increasing the supply flow rate of the inert gas and the supply flow rate of the organic solvent as the number of substrates to be processed increases;
The substrate processing method according to claim 6 . Counting the number of substrates to be processed before the substrates are carried into the drying tank.
The substrate processing method according to claim 6 or 7 . changing a supply flow rate of the organic solvent during the supply of the mixed gas to the drying tank.
The substrate processing method according to claim 6 . supplying the mixed gas into the drying tank after immersing the substrate in the treatment liquid and before lifting the substrate from the treatment liquid, and subsequently supplying the mixed gas into the drying tank when lifting the substrate from the treatment liquid.
The substrate processing method according to claim 6 .

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