TWI698283B - Processing liquid supply device, operation method of processing liquid supply device, and memory medium - Google Patents

Abstract

When the processing liquid is supplied to the substrate through the processing liquid supply path formed by the insulating flow path member, the charge amount of the processing liquid and the flow path member can be grasped.

The electrode rod (71) used as the first electrode is provided in contact with the processing liquid and the flow path member of the processing liquid supply path (2), and the electrode rod (71) is provided with a conductive plate (74) and a support (75) ) For the cover of the conductor (76). In addition, a surface potential measuring section (77) is provided so as to be close to the shielding conductor (76), and a display section (201) that displays the measured value of the surface potential is provided. If the treatment liquid flows to the insulating treatment liquid supply path 2, although the static electricity generated by friction will charge the treatment liquid and the flow path members, if the electrode rod (71) and the flow path are in close contact with each other, the surface potential The measuring unit (77) measures the amount of charge corresponding to the sum of the respective charge amounts of the treatment liquid and the flow path member as the surface potential of the first electrode. The measured surface potential is displayed on the display part (201).

Description

Processing liquid supply device, operation method of processing liquid supply device, and storage medium

The present invention relates to a processing liquid supply device that supplies a processing liquid to a substrate from a nozzle, an operating method of the processing liquid supply device, and a storage medium.

The vane type liquid processing apparatus used in the semiconductor manufacturing process, for example, ejects the processing liquid from the nozzle pair on the surface of the substrate supported on the turntable. The liquid treatment may be a treatment for forming a photoresist pattern and applying a photoresist liquid to a substrate, a treatment for supplying a developing solution to the exposed substrate, or a treatment for supplying and washing the substrate with a rinse solution, or the like. These kinds of processing liquids are supplied to the nozzles through piping with valves, filters, pumps and other equipment on the way.

It is known that the flow path including piping and equipment is made of insulating materials such as fluororesin from the standpoint of cleanliness and chemical resistance. If the processing liquid flows through the flow path, there will be a gap between the flow path and the processing liquid. The friction will generate static electricity. Depending on the type of treatment liquid and process conditions, there is a possibility that the amount of charge may increase, and there may be problems such as damage caused by electrostatic destruction of the members constituting the flow path, and degradation of the performance of the treatment process.

Patent Document 1 describes that by contacting with graphite electrodes It is a method of removing electricity by grounding the treatment liquid, but the high-purity graphite electrode may be damaged or defective. When it is assumed that elements other than graphite are contained, there will be a problem of impurities eluting into the treatment liquid and causing contamination. In addition, in the structure of Patent Document 1, it is difficult to cope with the charging amount because the charging amount status of the treatment liquid cannot be grasped.

[Prior Technical Literature] [Patent Literature]

[Patent Document 1] JP 2006-269677 A (paragraphs 0036, 0063, Figure 2, etc.)

In view of these circumstances, the present invention aims to provide a method for supplying a processing liquid to a substrate through a processing liquid supply path formed by an insulating flow path member by measuring the charge amount of the processing liquid as the surface potential. Technology to master the status of charged electricity.

Therefore, the processing liquid supply device of the present invention is a processing liquid supply device that supplies processing liquid from a nozzle to a substrate, and includes an insulating flow path member forming a processing liquid supply path for supplying the processing liquid to the nozzle; The first electrode of the processing liquid in contact with the processing liquid supply path; and a surface potential measuring section for measuring the surface potential of the first electrode.

In addition, the operating method of the processing liquid supply device of the present invention is an operating method of a processing liquid supply device that supplies processing liquid from a processing liquid supply path to a substrate through a nozzle, including: measuring the first processing liquid contacting the processing liquid supply path. The process of the surface potential of the electrode; and the process of displaying the surface potential measured by the foregoing process.

Next, a storage medium for storing a computer program used in the processing liquid supply device of the present invention, wherein the computer program is provided with a group of steps for executing the operation method of the processing liquid supply device.

According to the present invention, when the processing liquid is supplied to the substrate through the processing liquid supply path formed by an insulating flow path member, the charged state of the processing liquid is used as the surface potential of the electrode contacting the processing liquid of the processing liquid supply path. (Evaluation). Thereby, since the charging state of the treatment liquid can be grasped, it is helpful to obtain an appropriate response.

W: semiconductor wafer

100: Liquid processing module

11~13: nozzle

2: Processing liquid supply path

41: 1st grounding part

42: The second ground part

43: 3rd ground

51: The first measurement part

52: The second measurement section

53: The third measurement section

61: Charge control unit

62: Subsidy switching department

63: Voltage application part

631: Positive Power Supply Department

632: Negative Power Supply Department

633: Switching part for voltage switching

64: switching part

[Fig. 1] A configuration diagram of a processing liquid supply device related to the first embodiment of the present invention.

[Fig. 2] A characteristic diagram showing the relationship between surface potential value and time.

[Figure 3] A characteristic diagram showing the relationship between surface potential change and flow velocity.

[Fig. 4] A characteristic diagram showing the relationship between surface potential change and flow velocity.

[Fig. 5] A plan view and a longitudinal sectional view showing an example of a measuring unit provided in the processing liquid supply device.

[Fig. 6] A longitudinal sectional view showing an example of a measuring unit provided in the processing liquid supply device.

[Fig. 7] A configuration diagram showing an example of a charge amount control unit provided in the processing liquid supply device.

[Fig. 8] A longitudinal sectional view showing an example of a grounding portion provided in the processing liquid supply device.

[Fig. 9] A configuration diagram showing a control system of the processing liquid supply device.

[Fig. 10] An engineering drawing showing the function of the processing liquid supply device.

[Fig. 11] A characteristic diagram showing the relationship between surface potential value and time.

[Implementation form]

Fig. 1 shows a processing liquid supply device according to the first embodiment of the present invention. The processing liquid supply device supplies processing liquid (for example, a developing liquid) to the substrate (for example, semiconductor wafer, hereinafter referred to as "wafer") W from nozzles 11, 12, and 13; , 13 The processing liquid supply path 2 for supplying the processing liquid. The processing liquid supply path 2 is formed of an insulating flow path member, and a processing liquid supply source not shown in the figure is connected to the upstream end thereof. Flow path components, such as PFA (tetrafluoroethylene ‧ perfluoroalkyl vinyl ether Copolymer), PTFE (polytetrafluoroethylene) and other fluororesin pipes. FIG. 1 shows the downstream side of the processing liquid supply source in the processing liquid supply path 2 and includes supply devices such as valves and pumps, and in this example, devices related to controlling the processing liquid and controlling the charge amount of the flow path member.

First, supply equipment such as valves and pumps will be described. The processing liquid supply path 2 is provided with a first valve V1, a regulator 31, and a pump unit 32 in this order from the upstream side. The first valve V1 is a valve for supplying the processing liquid from the processing liquid supply source side to the processing liquid supply device, and a branch passage 20 including an exhaust valve V2 is connected to the upstream side of the first valve V1. The regulator 31 is a device that reduces the pressure of the processing liquid flowing through the processing liquid supply path 2 on the upstream side.

The regulator 31 includes, for example, a diaphragm and a valve linked to the diaphragm, and the pressure loss is adjusted by the opening degree of the valve. The pump unit 32 discharges the processing liquid from the nozzles 11, 12, and 13, and includes, for example, a pump 321 formed by a diaphragm pump, a supply valve V3 for supplying the processing liquid to the pump 321, and discharge from the pump 321 to the downstream side Valve V4 is used to discharge the treatment liquid. In addition, the pump 321 is connected to a drain passage 322 provided with a drain valve V5.

In this example, the processing liquid supply path 2 is branched into three on the downstream side of the discharge valve V4, and the branched processing liquid supply paths are called the first flow path 21, the second flow path 22, and the third flow path. twenty three. At the downstream ends of the first flow path 21, the second flow path 22, and the third flow path 23, nozzles 11, 12, and 13 are respectively provided. The nozzles 11, 12, and 13 are used to supply the same type of processing liquid as the wafers transported to the liquid processing module 100. The liquid processing module 100 for development processing is provided with, for example, a wafer W for forming a wafer W around a vertical axis. The substrate support portion 110 that is free to rotate and support.

The first flow path 21, the second flow path 22, and the third flow path 23 are provided with a filter 33, a flow rate detection unit 34, and a distribution valve (liquid discharge valve) V6 in this order from the upstream side of each. The distribution valve V6 is a device with a function of discharging a predetermined amount of processing liquid. The filter 33 removes particles contained in the processing liquid, and includes an exhaust passage 331 with an exhaust valve V7. In this example, the valves V1 to V7 are composed of pneumatic valves, for example. 35 in Figure 1 is the pressure detection part.

Before explaining the charging amount control equipment of the treatment liquid installed in the treatment liquid supply path 2, firstly use FIGS. 2 to 4 to describe the knowledge about the charging state of the treatment liquid. The insulating flow path member forming the processing liquid supply path 2 tends to be negatively charged, and the processing liquid tends to be positively charged. Therefore, if the processing liquid is circulated in the processing liquid supply path 2, static electricity will be generated due to the friction between the flow path member and the processing liquid. In the area of high pressure and high flow velocity in the processing liquid supply path 2, the frictional force will increase and become charged. The amount will also increase.

2 is a characteristic diagram showing the relationship between the surface potential value and time at the position near the upstream side (RegIN) and the position near the downstream side (RegOUT) of the regulator 31 of the processing liquid supply path 2. The surface potential value is set by the surface described later Obtained by the potential measurement department. Figure 2(a) shows when the pressure loss is large, and Figure 2(b) shows when the pressure loss is small, respectively use the dotted line in the figure to mark RegIN data and the solid line to mark RegOUT data. It can be seen from Figure 2 that if the supply path is discharged from the nozzles 11, 12, and 13, in order to allow the processing liquid to circulate in the processing liquid supply path 2, the surface potential of the processing liquid supply path 2 changes. It can be found that when the pressure loss is large Time is small compared to the loss At times, the amount of change is large.

Fig. 3 is a characteristic diagram showing the relationship between the surface potential changes at RegIN and RegOUT positions in the processing liquid supply path 2 and the average flow velocity in the pipe. Fig. 3(a) is the data of RegIN, and Fig. 3(b) is the data of RegOUT . The average flow rate is adjusted by the opening degree of the regulator 31. The larger the opening degree, the greater the flow rate and the smaller the pressure loss. The so-called surface potential change is the difference between the measured value of the surface potential and the initial value (when the liquid does not flow before the treatment liquid is discharged). As a result, in RegIN, the greater the pressure loss, the greater the negative value of the surface potential change, and in RegOUT, the greater the pressure loss, the greater the positive value of the surface potential change.

4 is a characteristic diagram showing the relationship between the surface potential changes at RegIN and RegOUT positions in the processing liquid supply path 2 and the average flow velocity in the pipe when the flow rate is adjusted by a pump installed on the upstream side of the first valve V1. Fig. 4(a) is the data of RegIN and Fig. 4(b) is the data of RegOUT. The situation where the regulator 31 is set is marked as △, and the situation where the regulator 31 is not set is marked as ◇. When the opening degree of the regulator 31 is fixed, the pressure loss becomes large when the regulator 31 is installed, and there is almost no pressure loss when the regulator 31 is not installed. From this result, in RegIN, when the average flow rate is larger (the pump's pressing force is larger), the negative value of the surface potential change becomes larger, and when the pressure loss is larger, the surface potential change also becomes larger. Big. On the other hand, it can be confirmed that in RegOUT, when the pressure loss is large, the greater the average flow rate, the greater the positive value of the surface potential change, but when there is almost no pressure loss, the greater the average flow rate, the negative value of the surface potential change Will also become bigger.

According to Figure 2~Figure 4, when the pressure loss is large, by In the flow of the processing liquid, the surface potential in RegIN changes to the negative side, and the surface potential in RegOUT changes to the positive side. The reason for this change is that when the pressure loss is large, the processing liquid tends to be highly positively charged and the flow path members tend to be highly negatively charged due to the flow of the processing liquid with high hydraulic pressure and the large pressure change in the regulator 31. . Therefore, it is presumed that the reason is that at the RegIN position, because the treatment liquid moves to the downstream side, it helps to increase the negative charge state of the flow path member. At the RegOUT position, although the charging amount of the treatment liquid and the flow path member is small, The highly positively charged treatment liquid is sent to the measuring point, which helps to increase the positively charged state of the treatment liquid side.

From the above results, it can be seen that the amount of charge of the treatment liquid and the flow path members varies depending on the magnitude of the pressure loss in the treatment liquid supply path 2 and the magnitude of the flow velocity. When the pressure loss in the processing liquid supply path 2 is large and the flow velocity is large, the frictional force between the processing liquid and the flow path member will increase, and the charge amount will also increase. Therefore, in the embodiment of the present invention, as will be described later, the flow path member is grounded at a location where a large pressure loss occurs, or in order to suppress the charge amount of the processing liquid discharged from the nozzle to the wafer W, at a position near the nozzle, It is constructed to control the amount of charge of the treatment liquid and the sum of the charge amount of the flow path member. Regarding the monitoring of the charge amount, it is sufficient to monitor only the charge amount of the treatment liquid. However, as described later, in order to ensure the airtightness of the flow space of the treatment liquid, the electrode used for monitoring the charge amount has a structure closely attached to the flow path member. In the embodiment, the sum of each charge amount of the treatment liquid and the flow path member is monitored.

Next, return to the description of the reduction in the charge amount of the processing liquid installed in the processing liquid supply path 2, and the measurement or control equipment from the first valve The upstream side of the door V1 is provided with a first grounding portion 41 and a first measuring portion 51 in order, and a second grounding portion is provided between the first valve V1 and the regulator 31, and between the regulator 31 and the supply valve V3, respectively 42 and the third ground portion 43. In addition, a second measuring section 52 is provided between each of the first flow path 21, the second flow path 22, and the third flow path 23, the filter 33 and the flow rate detection section 34, and the distribution valve V6 and the nozzles 11, 12, Between 13, the charge amount control unit 61 and the third measuring unit 53 are provided in order from the upstream side. In addition, since the first flow path 21, the second flow path 22, and the third flow path 23 are similarly provided with a supply device and a device related to charge amount control, the symbols are shared.

First, the first to third measuring parts 51 to 53 will be explained. The first to third measurement units 51 to 53 have the same configuration, and this example is shown in FIGS. 5 and 6 using the third measurement unit 53 as an example. The first to third measurement sections 51 to 53 include electrode units 7. The electrode unit 7 is composed of an electrode rod 71 and a liquid-contact area forming member 72. The electrode rod 71 of the third measurement section 53 is formed of a first electrode, and is, for example, a rod-shaped body having a circular cross-sectional shape, and the upper end thereof is formed in, for example, a circular planar shape.

The wetted part of the electrode rod 71, for example, on the metal surface of stainless steel, etc., in order to prevent the occurrence of metal contamination, the conductive material is formed by coating, and the conductive material is formed so that the treatment liquid does not penetrate the metal area. The thickness is, for example, a film thickness of 300 μm. As the conductive material, you can use: EC series (manufactured by Nisshinbo Chemical Co., Ltd.) and other conductive or electrostatic diffusivity (≦10 ⁹ Ω) fluororesin, AC140S (manufactured by Nisshinbo Chemical Co., Ltd.), AC140 (manufactured by Nisshinbo Chemical Co., Ltd.) ) And other glassy carbon, silicon carbide (SiC), etc.

The wetted area forming member 72 is, for example, detachably installed in the processing liquid supply path 2 to support the electrode rod 71, and form a wetted area between the electrode rod 71 and the processing liquid. The road members are made of the same insulating material. The example liquid contact area forming member 72 includes a flow portion 721 formed along the processing liquid supply path 2 to flow the processing liquid, and a support portion 722 that is formed integrally with the flow portion 721 and supports the electrode rod 71. The support portion 722 is formed substantially perpendicular to the flow portion 721 from a substantially central portion in the longitudinal direction of the flow portion 721, and has an insertion port 723 of the electrode rod 71 at the upper end. The support portion 722 is in contact with the outer surface of the electrode rod 71 on its inner surface, for example. When the electrode rod 71 is inserted into the support portion 722, for example, the tip portion of the electrode rod 71 is configured to contact the processing liquid flowing through the circulation portion 721. The electrode rod 71 is connected to the support part 722 by, for example, a screw-type joint part 711, so that the electrode rod 71 is provided in contact with the processing liquid and the flow path member of the processing liquid supply path 2.

Such a liquid contact area forming member 72 is connected to the processing liquid supply path 2 by, for example, screw-type joints 731 and 732, and serves as a part of the flow path member. In addition, the electrode rod (first electrode) 71 is located in the first flow path 21, the second flow path 22, and the third flow path 23, respectively, near the discharge ports of the nozzles 11, 12, and 13, for example, along the treatment liquid from the discharge ports. The supply path 2 is provided at a position of 100 mm to 3000 mm, for example. The joint portions 711, 731, and 732 are made of, for example, insulating fluororesin made of the same material as the processing liquid supply path 2.

On the electrode rod 71 of the electrode unit 7, as shown in the plan view of FIG. 5(a) and the longitudinal sectional view of FIG. 5(b), for example, a disc-shaped guide is provided. Electric board 74. The conductive plate 74 constitutes a part of the first electrode. For example, the center portion thereof is configured to be aligned with the center portion of the cross section of the electrode rod 71, and a shielding conductor 76 is provided on the upper surface via a cylindrical support 75, for example. The support 75 is formed of, for example, an insulating member such as PEEK (polyether ether ketone), and the conductive plate 74 and the shielding conductor 76 are formed of, for example, a stainless steel material such as SUS316L.

The shielding conductor 76 is configured to cover the side circumference of the electrode rod 71 with a space interposed therebetween, for example, a cylindrical shape. The upper end is bent inward. When viewed from above, the central part is, for example, a ring-shaped upper surface with a circular opening. 761 to form. The back side of the upper surface portion 761 is connected to the upper end of the support body 75, and the opening 762 in the center of the upper surface portion 761 is formed inside the support body 75. The shielding conductor 76 is grounded in order to shield an external electric field, and the opening 762 is formed concentrically with the conductive plate 74, for example.

As shown in FIG. 6, the first to third measurement sections 51 to 53 include a surface potential measurement section 77 that measures the surface potential of the first electrode (electrode rod 71 ), in this example, the surface potential of the conductive plate 74. The surface potential measuring section 77 is provided near the upper surface 761 of the shielding conductor 76 (for example, the upper side 10 mm higher than the upper surface 761), and the measuring end is close to the opening surrounded by the shielding conductor 76 ( The position of the opening above the conductive plate 74) is provided. As mentioned above, if the processing liquid is passed through the processing liquid supply path 2, the processing liquid will be positively charged and the flow path member will be negatively charged. By contacting the first electrode (electrode rod 71), the charge is caused The electric power lines of φ will be condensed in the area surrounded by the first electrode, the conductive plate 74 and the shielding conductor 76. Surrounded by conductive plate 74 and shielding conductor 76 Because the area shields the external electric field, it is equal to the internal potential. This potential corresponds to the surface potential of the conductive plate 74 which is a part of the first electrode.

The surface potential measurement unit 77 is equipped with a measurement electrode that induces a voltage corresponding to the electrostatic capacitance between the object to be measured, and periodically oscillates the measurement electrode to take out an AC modulated signal to grasp the surface Potential. As the surface potential measuring section 77, for example, a surface potentiometer such as ZJ-SD manufactured by OMRON Corporation can be used.

By providing the surface potential measuring section 77 facing the conductive plate 74 in this way, the charge amount of the processing liquid and the flow path member is measured as the surface potential of the first electrode potential (surface potential of the conductive plate 74). As mentioned above, in this embodiment, since the electrode rod 71 is in close contact with the liquid-contact area forming member 72 forming part of the flow path member, the above-mentioned surface potential corresponds to the charged state of the combined treatment liquid and the charged state of the flow path member. This measured value is output to the control part 200 mentioned later. In addition, the shielding conductor 76 may not be used.

The first measuring unit 51 is provided on the upstream side of the first valve V1 in order to grasp the charged state of the processing liquid supplied from the processing liquid supply source to the processing liquid supply device, and the second measuring unit 52 is provided to determine whether the filter 33 is clogged And bubbles are generated, and are provided on the downstream side of the filter 33. In addition, the third measurement unit 53 is provided near the upstream side of the nozzles 11 to 13 in order to grasp the charged state of the processing liquid supplied to the nozzles 11 to 13.

Next, an example of the charge amount control unit 61 will be described with reference to FIG. 7. The charge control unit 61 in this example is the same as the first to third surface potential measuring units 51 to 53 and includes: an electrode unit 7, a conductive plate 74, The support 75 and the shielding conductor 76; the electrode rod 71 of the electrode unit 7 corresponds to the second electrode. The electrode rods (second electrode) 71 are respectively provided in the first flow path 21, the second flow path 22, and the third flow path 23. For example, the electrode rod (first electrode) 71 of the third measuring section 53 is supplied along the treatment liquid Path 2 is set at a position of 10mm~5000mm on the upstream side.

The electrode rod (second electrode) 71 is connected to the voltage applying unit 63 via the auxiliary switching unit 62. The auxiliary switching part 62 is used to switch the connection end of the electrode rod 71 between the voltage applying part 63 or the grounding part. In addition, the voltage application unit 63 applies a voltage to the electrode rod 71 based on the surface potential measurement value obtained from the surface potential measurement unit 77 of the third measurement unit 53 and controls the charge amount of the treatment liquid and the flow path member. The voltage application section 63 in this example, as shown in FIG. 7, includes: a positive power supply section 631 for positive voltage application, a negative power supply section 632 for negative voltage application, and switches between which the positive power supply section 631 and the negative power supply section 632 are connected. Switching section 633 for voltage switching. Furthermore, in this example, since the electrode rod 71 which is the second electrode is also in close contact with the flow path member, not only the treatment liquid but also the charge amount of the flow path member is controlled.

Furthermore, the voltage applying unit 63 includes a switching unit 634 for setting the electrode rod 71 to the positive power supply unit 631 or the negative power supply unit 632 in a connected state or a disconnected state. Each switching unit, for example, has two relay switches in parallel, and one of them is turned on by the energization of the relay unit, and the other is turned off, thereby enabling the switch contacts to be used as a switching relay circuit. In addition, the charging amount control unit 61 may not be provided with the shielding conductor 76.

Next, the first to third ground portions 41 to 43 will be described. The first to third grounding portions 41 to 43 have the same structure, and the An example is shown in FIG. 8 taking the first ground portion 41 as an example. The first to third ground portions 41 to 43 are provided with an electrode unit 7 having the same configuration as the first to third measuring portions 51 to 53, and the electrode rod 71 corresponds to the third electrode. The electrode rod (third electrode) 71 is connected to the ground state and the open state by switching the grounding section 44.

As shown in FIG. 9, the liquid processing apparatus including the processing liquid supply device and the liquid processing module 100 is provided with a control unit 200 constituted by a computer; the control unit 200 has a program storage unit not shown in the figure. The program storage unit stores, for example, a program composed of software, which combines commands for charge amount control and liquid treatment in the liquid treatment module 100 described in the action described later. By reading the program to the control unit 200, the control unit 200 outputs control signals to various parts of the liquid treatment device. This controls the opening and closing of the valves V1 to V7, the driving of the pump unit 32, the grounding of the electrode rod 71 and the application of voltage to the electrode rod 71, the movement of the nozzles 11 to 13, and the driving of the substrate support portion 110. The charge amount control and liquid treatment can be carried out. The program is stored in the program storage section in a state of being stored in a storage medium such as a hard disk, an optical disk, a magneto-optical disk, or a memory card.

Next, the control of the charge amount will be continued. As shown in FIG. 9, the control unit 200 includes a display unit 201 that simultaneously displays the surface potential detected by the surface potential measurement unit 77 of the first to third measurement units 51 to 53. For example, the display unit 201 monitors the analog output value corresponding to the surface potential. Furthermore, the control unit 200 is equipped with: for example, each of the surface potential measurement values detected by the first to third measurement units 51 to 53 is determined to determine whether the measurement value is within an appropriate range, and the measured surface potential exceeds the appropriate range. Out of range The function to output warnings. The warning is output, for example, by the warning output unit 202 such as a warning sound generating unit and a warning lamp. The appropriate range of the surface potential is set for each of the first to third measuring parts 51 to 53 in each processing program, for example.

In addition, the control unit 200 controls the auxiliary switching unit 62 of the charge amount control unit 61, the switching unit 633 for voltage switching, and the switching unit 634 in accordance with the processing program. Specifically, the switching unit 633 for voltage switching compares the measured surface potential value obtained from the third measuring unit 53 with the target value, and controls the connection to the negative when the measured value deviates from the target value to the positive side. The power supply unit 632 controls the connection to the positive power supply unit 631 when the measured value deviates to the negative side from the target value. Furthermore, when the target value of the surface potential is 0 potential and when the discharge of the processing liquid is stopped (when the processing liquid does not flow to the processing liquid supply path 2), the control auxiliary switching unit 62 switches the connection end to the grounding unit.

Furthermore, when the target value of the surface potential is outside the zero potential, the positive power supply unit 631 or the negative power supply unit 632 is repeatedly switched between the connection state and the disconnection state, such as PWM (pulse width modulation) or The PID method controls the switching unit 634.

In the process of supplying the processing liquid from the nozzle to the wafer W, there are a plurality of steps; the target value of the surface potential corresponds to each of the aforementioned plural steps and is set in the processing program in advance. In addition, the period of intermittently connecting the positive power supply unit 631 or the negative power supply unit 632 by the switching unit 634 is preset for each processing program. These target values and cycles are set by conducting experiments to optimize in advance, and the cycle corresponds to the discharge time The flow rate of the treatment liquid is optimized. When the target value of the surface potential is 0 potential, connect the electrode rod (second electrode) 71 to the ground side, and when the target value is other than 0 potential, connect the electrode rod (second electrode) 71 to the voltage periodically The applying unit 63 controls the connection end to switch to the positive power supply unit 631 side or the negative power supply unit 632 side based on the measured value of the surface potential corresponding to the target value.

Then, the first to third grounding parts 41 to 43 correspond to the processing program. When the processing solution is passed through the area where the first to third grounding parts 41 to 43 are installed, the electrode rod (third electrode) 71 is grounded and placed in the aforementioned area. When the treatment liquid does not flow, the electrode rod 71 is switched from the grounded state to the open state to control the grounding switching unit 44. Conversely, it is also possible to switch the electrode rod (third electrode) 71 from the grounded state to the open state when the treatment liquid is passed through the area where the first to third grounding parts 41 to 43 are provided, and when the treatment liquid is not passed through the aforementioned area , The grounding switching unit 44 is controlled to switch the electrode rod 71 to the grounded state.

Next, the function of this embodiment will be explained. The processing liquid supply path 2 opens the first valve V1 to supply the processing liquid at a predetermined pressure from the processing liquid supply source side. First, the first valve V1 and the supply valve V3 are opened, the pump unit 32 is activated, and a certain amount of processing liquid is stored in the pump 321. Then, the valve V5 is opened to discharge the processing liquid through the drainage path 322, and the processing liquid in the pump 321 is defoamed. Next, the valve V5 is closed and the discharge valve V4 is opened to activate the pump unit 32. When the processing liquid circulates through the filter 33, for example, the processing liquid fills up the processing liquid supply path 2 on the upstream side of the distribution valve V6.

Then, when the treatment liquid is discharged from nozzles 11~13, When the element 32 is activated, the distribution valve V6 is opened for a predetermined time. Thereby, in each liquid processing module 100, the processing liquid is discharged from the nozzles 11 to 13 to the wafer W for a predetermined time, and liquid processing is performed. When the processing liquid is discharged from the nozzles 11 to 13, the first valve V1, the supply valve V3, and the discharge valve V4 are also opened, and the processing liquid is supplied to the processing liquid supply path 2 from the processing liquid supply source side. When the nozzles 11 to 13 stop discharging the treatment liquid, the distribution valve V6 is closed.

When the first valve V1 is opened and the processing liquid is supplied from the processing liquid supply source, the surface potentials measured by the first to third measuring sections 51 to 53 are output to the control section 200 and displayed on the display section 201. For example, the surface potential ( Charge) is there any abnormality. Therefore, for example, when the surface potential deviates from an appropriate range, a warning output is performed at the warning output unit 202, and the operator is notified of the abnormality of the charge amount.

For example, because the first measuring unit 51 is provided on the upstream side of the first valve V1, a warning is output when the processing liquid exceeding the proper range of the surface potential is supplied from the processing liquid supply source side. In addition, because the second measuring unit 52 is provided between the filter 33 and the flow rate detection unit 34, such as the passage of the regulator 31, the pump unit 32, and the filter 33, when the charge amount of the treatment liquid exceeds an appropriate range and becomes larger , Output a warning. Furthermore, since the third measuring unit 53 is provided near the nozzles 11, 12, and 13, even if the charge amount control described later is performed, when the charge amount of the processing liquid supplied to the wafer W exceeds an appropriate range, a warning is output.

Next, regarding the control of the amount of charge, the situation when the developer as a processing liquid is supplied to the wafer W for development processing is taken as an example Bright. FIG. 10 schematically shows the liquid processing module 100 that performs development processing. The liquid processing module 100 is provided with, for example, two types of nozzles for supplying the developing liquid, one of which is a straight tubular nozzle with a discharge port at the bottom, and the other is a nozzle with a slit-shaped discharge port of approximately 20 mm. Rectangular nozzle. These nozzles, for example, are integrally formed by a common moving mechanism (not shown in the figure) and can move freely in the diameter direction of the wafer W. For example, a straight tube nozzle corresponds to the above-mentioned nozzles 11, 12, and 13. Here, for convenience, the straight pipe-shaped nozzle is referred to as the auxiliary nozzle 11, and the rectangular nozzle is referred to as the main nozzle 14 to continue the description. With respect to the auxiliary nozzle 11 and the main nozzle 14, the processing liquid, that is, the developing liquid, is supplied by a processing liquid supply device of a separate system.

First, with the wafer W being rotated, a pre-wetting liquid (for example, pure water) is supplied to the approximate center of the wafer W from a nozzle not shown in FIG. 10. In this step, in the respective processing liquid supply paths 2 of the auxiliary nozzle 11 and the main nozzle 14, the developing liquid is not discharged from each nozzle. Therefore, in each processing liquid supply path 2, for example, the electrode rods (third electrodes) 71 of the first to third grounding parts 41 to 43 are set to be opened from the ground, and the electrode rods (third electrode) of the charge control unit 61 (2 electrodes) 71 is set to a grounded state.

Next, as shown in FIG. 10(a), in the processing liquid supply path 2 of the auxiliary nozzle 11, the target value of the surface potential is set to a negative potential (-E1V), and the wafer W is rotated by the number of revolutions R1, The developing liquid is supplied from the auxiliary nozzle 11 to the approximate center of the wafer W. In this step, since the developer is discharged, for example, the first to third grounding portions 41 to 43 make the electrode rod (third electrode) 71 grounded by the switching portion 44 shown in FIG. 8.

In addition, because the target value of the surface potential is negative, the charge The control unit 61 first switches the connection end of the electrode rod (second electrode) 71 to the voltage application unit 63 side through the auxiliary switching unit 62, and switches the voltage switching unit 633 to the negative power supply unit 632 side. Therefore, the switching unit 634 periodically repeats the connection state and the disconnection state, and compares the measured value of the surface potential obtained by the third measuring unit 53 with the target value in this state. If the measured value deviates from the target value to the negative side, switch the voltage switching section 633 to the positive power supply section 631 side, and when the measured value deviates from the target value to the positive side, switch the voltage switching section 633 To the side of the negative power supply 632.

In this case, in accordance with the difference between the measured value of the surface potential and the target value, the duty ratio (the ratio of the ON time relative to the total of the ON time and the OFF time) of the switching unit 634 on and off is adjusted. For example, when the measured value is low (large absolute value) compared to the negative target value of the surface potential, the greater the difference between the measured value of the surface potential and the target value, the greater the load ratio, so that the The amount of positive charge increases, and the smaller the difference between the measured value of the surface potential and the target value, the smaller the duty ratio, and the amount of positive charge supplied to the electrode rod 71, for example, decreases. In addition, when the measured value coincides with the target value, the state where the load ratio is 0 is maintained, that is, the state where the switching unit 634 is cut off is maintained. Thereby, a control operation is performed to bring the measured value of the surface potential close to the target value. In addition, the target value may be, for example, a voltage range that is maintained within an allowable range with respect to the target voltage value.

In addition, this PWM control is not limited, and it is also possible to supply positive or negative charges to the electrode rod 71 by methods such as PID control.

Then increase the number of revolutions of wafer W to R2 and set this The surface potential target value (-E2V) corresponding to the number of revolutions R2 is supplied from the auxiliary nozzle 11 to the approximate center of the wafer W. The higher the number of revolutions, the greater the friction force of the developer on the surface of the wafer W. Because the charge amount of the developer changes, the target value of the surface potential corresponding to the number of revolutions is set. In fact, because the number of revolutions is increased in stages, the target value of the surface potential is set for each number of revolutions.

Next, the discharge of the developing liquid from the auxiliary nozzle 11 is stopped, and the auxiliary nozzle 11 and the main nozzle 14 are moved to the peripheral side of the wafer W. After that, as shown in FIG. 10(b) and (c), in the state of rotating the wafer W, move the main nozzle 14 along the diameter of the wafer W, for example, from the peripheral portion to the center portion, and simultaneously eject the developed image liquid. Set the target value of the surface potential so that it is positive (+E3V) on the peripheral side and 0 (0V) in the center. The target value of the surface potential is changed from +E3V to 0V according to the position on the wafer W Decrease the setting. In this case, too, when the target value is not zero potential, based on the measured value of the surface potential, a positive voltage or a negative voltage is applied to the electrode rod (the second electrode 71) corresponding to the target value as described above. In addition, when the target value is set to 0 potential, the connection end of the electrode rod (second electrode) 71 is switched to the grounding part by the auxiliary switching part 62.

Next, the discharge of the developing liquid from the main nozzle 14 is stopped, and the auxiliary nozzle 11 and the main nozzle 14 are retracted to the peripheral side of the wafer W. Next, while the wafer W is being rotated, a rinse solution (such as pure water) is supplied to the wafer W for cleaning, and while the wafer W is being rotated, nitrogen is supplied to the wafer W and dried, and the wafer W is stopped. Of rotation. In the above steps, when the auxiliary nozzle 11 and the main nozzle 14 stop discharging the treatment liquid, In the supply path 2, the electrode rods (third electrode) 71 of the first to third ground portions 41 to 43 are set to be opened from the ground, and the electrode rod (second electrode) 71 of the charge control portion 61 is set to Grounded state.

According to the above-mentioned embodiment, when the processing liquid is supplied to the wafer W through the processing liquid supply path 2 formed by the insulating flow path member, the sum of the respective charge amounts of the processing liquid and the flow path member corresponds to The amount of charge is measured as the surface potential of the conductor. As a result, since the charged state of the processing liquid and the flow path members in the processing liquid supply path 2 can be grasped, when the surface potential is too high or the surface potential drops sharply, the warning output unit 202 outputs a predetermined warning, so that appropriate responses can be taken. .

In addition, the surface potential is measured with the processing liquid flowing through the processing liquid supply path 2, and the charged state of the processing liquid that changes due to the flow can be grasped immediately by the displayed content. In a state where stress is applied to the fluororesin constituting the processing liquid supply path 2, cracks are likely to occur if it comes into contact with an organic solvent. On the other hand, the application of negative photoresist is increasing, and there is a tendency to use butyl acetate with a large volume resistivity as a developer. However, if the volume resistivity is high, static electricity caused by friction with flow path members will be increased. Increases rapidly and accumulates static electricity. Therefore, in equipment with a large pressure loss such as the regulator 31, the static charge will be concentrated in the part of the micro crack, and the fluororesin may be destroyed.

In addition, as the method of circulating the treatment liquid without retaining it becomes the mainstream, the treatment liquid and the flow path members will accumulate electric charge and increase the amount of charge. Because of this, it becomes effective to grasp the surface potential of the processing liquid in the processing liquid supply path 2. In addition, when the processing liquid is supplied from the processing liquid supply source to the plural processing liquid supply devices, the first valve in each processing liquid supply device The first measuring unit 51 is provided on the upstream side of V1. Therefore, it is possible to grasp whether there is a deviation in the charge amount of the processing liquid between the processing liquid supply devices.

Furthermore, by providing the second measurement unit 52, abnormalities such as clogging of the filter 33 and mixing of air bubbles can be detected. FIG. 11 is a characteristic diagram showing the relationship between the surface potential value and time at the position near the upstream side (FilIN) and the position near the downstream side (FilOUT) of the filter 33 of the processing liquid supply path 2. Fig. 11(a) shows the data at normal time, and Fig. 11(b) shows the data at abnormal time with tens of bubbles mixed in. In the figure, the dotted line indicates the data of FilIN, and the solid line indicates the data of FilOUT. It can be understood from this figure that when the treatment liquid is discharged from the nozzles 11, 12, and 13, the surface potential changes greatly. However, if bubbles are mixed in the filter 33, the surface potentials of FilIN and FilOUT will have small peaks. By grasping the surface potential near the filter 33 in this way, the abnormality of the filter 33 can be detected.

Furthermore, the present invention is based on the measured value of the surface potential of the third measuring section 53, because a voltage is applied to the electrode rod (second electrode) 71, and the charge amount of the treatment liquid and the flow path member can be controlled through the electrode rod 71. In this way, when the charge amount and the flow velocity are too large and the grounding alone cannot sufficiently eliminate the electricity, the electricity can be eliminated reliably. In addition, it is possible to suppress the occurrence of accidents such as leakage and ignition caused by electrostatic destruction of the flow path member due to excessively high charging amount, and it is also possible to suppress the decrease in the accuracy of measurement equipment such as the flow rate detection unit 34. In addition, since a positive voltage or a negative voltage is applied to the electrode rod (second electrode) 71 based on the measured value of the surface potential and the target value, appropriate control can be performed and the surface potential can be quickly brought close to the target value. Furthermore, by providing the auxiliary switching section 62 and the switching section 634 in the charge control section 61, the electrode rod (second electrode) 71 is grounded. It can be connected to the voltage applying section 63 intermittently, and high-precision control that matches the target value of the surface potential can be performed more easily.

Since the charge amount of the processing liquid can be controlled, the potential distribution in the surface of the wafer W can be improved during liquid processing. The insulating processing liquid is always positively charged due to the flowing charge. If the processing liquid is supplied while the wafer W is rotating, the thin film on the wafer W is negatively charged at the center extreme, and the closer it is to the periphery, the closer it is to 0. Potential distribution of potential. Due to the potential deviation in the surface of the wafer W, for example, when the size of the wiring pattern is measured on the wafer by an inspection machine (SEM: Scanning Electron Microscope), the measurement cannot be made due to blurred images, or design deviations occur. , Leakage residue is easily left partially. In addition, if the treatment liquid is charged, the current flows through the treatment liquid discharged from the nozzles 11 to 13, so that film peeling, electrostatic breakdown of the circuit, bending of the discharge track, rebound of the discharge liquid, etc. occur near the dropping position of the treatment liquid. By controlling the charge amount of the treatment liquid, these things can be prevented from happening.

In addition, because the electrode rod (first electrode) 71 of the third measuring part 53 and the electrode rod (second electrode) 71 of the charge control part 61 are provided from the discharge ports of the nozzles 11 to 13 without a large pressure loss part , Installed at a position within 5000mm, can make the charge amount close to the target value to discharge the treatment liquid from the nozzles 11~13, which can ensure good process performance. Furthermore, even when a plurality of nozzles 11 to 13 are provided, the charge amount of the processing liquid discharged from each of the nozzles 11 to 13 can be collected. Furthermore, because the third measuring unit 53 is provided on the downstream side of the charge control unit 61 to measure the surface potential directly in front of the discharge ports of the nozzles 11 to 13, if the charge control unit 61 controls The amount of charge can also be used to grasp abnormalities in the amount of charge such as surface potential deviating from the appropriate range.

Furthermore, by installing the first to third grounding parts 41 to 43 and grounding, it is possible to use the various pressure loss parts of the processing liquid supply device even if the charge amount increases due to the processing liquid type and circulation conditions. Protect fluid machinery. In addition, because the switching unit 44 for grounding is provided, the grounding control can be performed only when the processing liquid flows through the processing liquid supply path 2 or only when the processing liquid does not flow through the processing liquid supply path 2, which can be efficiently performed when necessary. In addition to electricity.

In addition, the first to third grounding portions 41 to 43, the first to third measuring portions 51 to 53, and the charge control portion 61 are provided with a common electrode unit 7; formed with electrodes that are in contact with the processing liquid and flow path members. The electrode rod 71 has the same structure. Therefore, since the electrode rod 71 is used for grounding, surface potential measurement, and charge control of the applied voltage, the design and manufacture for charge control become easier. In addition, since the electrode unit 7 is detachably installed with respect to the flow path member, the grounding part, the measuring part, and the charging control part can be easily installed in a desired place. In addition, the electrode rod 71 is formed by coating a conductive material on a metal. While suppressing the occurrence of metal contamination, it can also perform neutralization by grounding of the treatment liquid and flow path members, measurement of surface potential, and control of the amount of charge. .

As described above, the processing liquid supply device can also be installed in such a way that the first electrode is in contact with the processing liquid and the flow path member to measure the surface potential and display it when the device is erected, during maintenance, or when the processing liquid is exchanged. , To grasp the charging state of the treatment liquid and flow path members. To master The grounding of the treatment liquid and flow path members, and the necessary positions for applying voltage to control the amount of charge.

In addition, the processing liquid is not limited to the developing liquid. For example, the present inventors have grasped that the charge amount of the rinse liquid (pure water) during cleaning has a correlation with the number of residues on the wafer W, and also confirmed whether the neutralization of the rinse liquid is effective. If an example of charge control during leakage processing is shown, for example, a rinse solution (pure water) can also be used for pre-wetting before supplying developer to wafer W, but the target value of the surface potential in this pre-wetting process is set as 0 potential. In the cleaning process after the supply of the developer solution, the target value of the surface potential is set to -E4V, and the rinse solution is supplied to the approximate center of the wafer W while the wafer W is rotated. After that, the rinse liquid and nitrogen for drying are supplied to the wafer W, but at this time, the target value of the surface potential is set to zero potential. The same is true when the processing liquid is a rinse liquid. When the processing liquid does not circulate to the processing liquid supply path 2 (the processing liquid is not discharged from the nozzle), when the processing liquid circulates to the processing liquid supply path 2, the target value is zero potential The control at other than 0 potential is the same as the above example.

In the above, the configuration of the first to third electrodes is not limited to the above-mentioned embodiment. The treatment liquid and the flow path member may be configured to contact each other, and the surface potential measurement unit may also measure the configuration of the first electrode. Electrical conductor surface potential. In addition, the voltage applying unit 63 does not necessarily need to include the switching unit 634, and the second electrode may be connected to the voltage applying unit 63 through the auxiliary switching unit 62. In this case, the measured value of the surface potential is compared with the target value, and when the measured value coincides with the target value, the auxiliary switching part 62 sets the voltage applying part 63 to the cut-off state. In addition, the electrode rod 71 forming the third electrode is not provided with the grounding switching part 44, but is directly connected Ground status connection is also possible. Furthermore, the display unit for displaying the surface potential can also be installed in the vicinity of the first to third measuring units 51 to 53, and at least one of the first electrode, the second electrode, and the third electrode can also be coated with a conductive fluororesin. cloth.

Furthermore, the charge amount control unit 61 corresponding to the first measurement unit 51 and the second measurement unit 52 is set separately, and based on the surface potential measurement values of the first measurement unit 51 and the second measurement unit 52, a voltage can also be applied to form a corresponding The electrode rod 71 of the second electrode performs charge control. Furthermore, the charge amount control unit 61 may be provided with a surface potential measurement unit 77. In this case, the first electrode also serves as the second electrode, the surface potential of the conductor corresponding to the potential of the first electrode is measured, and the voltage applied to the first electrode is controlled to control the amount of charge.

Furthermore, the above-mentioned treatment liquid supply path 2 has: a measuring part for measuring the surface potential, a display part for displaying the surface potential, a grounding part that connects the electrode rod to a grounded state, and a charge amount for controlling the charge amount by applying a voltage to the electrode rod Control part; but it may also have at least a measurement part. Next, a configuration including only the measurement unit, the display unit, and the grounding unit may be used, or a configuration including only the measurement unit, the display unit, and the charge amount control unit. In addition, the installation positions and the number of measuring parts, grounding parts, and charge control parts for measuring the surface potential are not limited to the above-mentioned examples. The coating and developing devices described above are not limited. For example, other liquid processing devices such as cleaning devices, etching devices, film forming devices, substrate bonding devices, exposure devices, inspection devices, etc. may be used. In addition, the semiconductor manufacturing process is not limited to the process of forming a semiconductor device on a semiconductor wafer, and forming a transistor manufacturing liquid on a glass substrate Crystal panel engineering is also possible.

2: Processing liquid supply path

11, 12, 13: nozzle

20: Branch Road

21: The first stream

22: Second stream

23: Third stream

31: regulator

32: Pump unit

33: filter

34: Flow detection department

35: Pressure detection department

41: 1st grounding part

42: The second ground part

43: 3rd ground

51: The first measurement part

52: The second measurement section

53: The third measurement section

61: Charge control unit

100: Liquid processing module

110: substrate support

321: Pump

322: Drainage

331: Exhaust Path

V1, V2, V3, V4, V5, V6, V7: Valve

W: semiconductor wafer

Claims (14)

A processing liquid supply device for supplying processing liquid from a nozzle to a substrate, comprising: an insulating flow path member forming a processing liquid supply path for supplying the processing liquid to the nozzle; an electrode rod, and a conductive plate on the upper surface of the electrode rod , And a first electrode of the shielding conductor; wherein the shielding conductor is provided on the top of the conductive plate via a support provided between the conductive plate and the shielding conductor; and measuring the first electrode The surface potential measuring part of the surface potential; wherein the electrode rod is inserted into the insulating flow path member and is in contact with the processing liquid in the processing liquid supply path; wherein the shielding conductor is grounded to shield the external electric field. The processing liquid supply device according to claim 1, further comprising: a display unit that displays the surface potential measured by the surface potential measurement unit. The processing liquid supply device according to claim 1 or 2, further comprising: a warning output unit that outputs a warning when the surface potential measured by the surface potential measurement unit exceeds an appropriate range. The processing liquid supply device according to claim 1 or 2, comprising: a second electrode contacting the processing liquid of the processing liquid supply path; and, based on the surface potential measurement value obtained by the surface potential measurement unit, the second electrode The electrode applies a voltage and controls the charge amount of the treatment liquid. The processing liquid supply device according to claim 4, wherein the voltage application unit further includes: a negative power supply unit for applying a negative voltage; a positive power supply unit for applying a positive voltage; and when the measured value is more positive than the target value In the case of side deviation, connect the negative power supply unit to the second electrode, and when the measured value deviates to the negative side from the target value, connect the positive power supply unit to the voltage switching switching unit of the second electrode. The processing liquid supply device according to claim 5, wherein an auxiliary switching part for switching the connection end of the second electrode between the voltage applying part and the grounding part is provided; the auxiliary switching part is when the target value is When the potential is 0, the connection end of the second electrode is switched to the ground. The processing liquid supply device according to claim 5, wherein the voltage applying portion causes the second electrode to alternately connect and disconnect the negative power supply portion or the positive power supply portion when the target value is other than 0 potential status. The processing liquid supply device according to claim 5, further comprising: a plurality of steps of the processing liquid supply process of supplying the processing liquid from the nozzle to the substrate; and the target value is determined corresponding to the plurality of steps. The processing liquid supply device according to claim 4, comprising: a third electrode that contacts the processing liquid of the processing liquid supply path; and when the processing liquid flows to the processing liquid supply path and does not flow to the processing liquid supply In one case of the circuit, the third electrode is switched to the grounded state, when the processing liquid flows to the processing liquid supply path and does not flow to the processing In another case in the case of the liquid supply path, the grounding switching unit switches the third electrode from the grounded state to the open state. The processing liquid supply device according to claim 9, wherein at least one of the first electrode, the second electrode, and the third electrode is coated with a conductive fluororesin. A method of operating a processing liquid supply device according to claim 1, comprising: a process of measuring the surface potential of a first electrode of the processing liquid in contact with the process liquid supply path; and a process of displaying the measured surface potential of the process. The method of operating a processing liquid supply device described in claim 11 includes a process of outputting a warning when the surface potential measured by the surface potential measurement unit exceeds an appropriate range. The method of operating a processing liquid supply device according to claim 11 or 12, comprising: a second electrode contacting the processing liquid of the processing liquid supply path; and applying a voltage to the second electrode based on the measured value of the surface potential , A voltage application unit for controlling the charge amount of the aforementioned treatment liquid. A storage medium for storing a computer program of a processing liquid supply device for supplying processing liquid from a nozzle to a substrate, wherein the computer program is provided with: in order to execute the operation of the processing liquid supply device described in any one of claims 11 to 13 Step group of method.

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