JP2003347206A - Coating method and coating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating method and a coating device capable of forming a coated film such as a resist film or the like with high film thickness accuracy and film thickness uniformity. <P>SOLUTION: This device comprises a substrate holding member 71 for almost horizontally holding a treatment substrate W, a motor 72 for rotating the substrate holding member 71, a coating agent injection nozzle for injecting a coating agent on the treatment substrate W held by the substrate holding member 71, a pump 97 for injecting the coating agent from a coating agent injection nozzle 90, a valve 94 provided in a pipe for supplying the coating agent to the coating agent injection nozzle 90, a detection means 100 for detecting the injection start of the coating agent from the coating agent injection nozzle 90, and a control means 110 for inputting a detection signal and controlling, based on the detection signal, at least one of the drive timing of the pump 97, the operation timing of the valve 94 and the drive start or stop timing of the motor 72. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating method and a coating apparatus for coating a substrate such as a semiconductor wafer with a coating liquid such as a resist.

[0002]

2. Description of the Related Art In a semiconductor device manufacturing process, for example, a resist solution is supplied to a surface of a semiconductor wafer (hereinafter, simply referred to as a "wafer") to form a resist film, and a predetermined resist is applied to the wafer after resist application. A resist pattern is formed as a mask for forming a predetermined pattern by a so-called photolithography technique of performing an exposure process corresponding to the pattern described above and then developing an exposure pattern formed on the resist film of the wafer. In the resist coating process among the above steps, a spin coating method is often used as a method for uniformly applying a resist liquid on a wafer surface.

FIG. 16 shows an outline of the spin coating method. For example, in a state where the wafer W is fixedly held by vacuum suction by the spin chuck 161, while rotating the wafer W together with the spin chuck 161 by a rotation driving unit (not shown), the surface of the wafer W is transferred from the resist nozzle 162 disposed above the wafer W. A resist solution is dropped at the center. The dropped resist liquid spreads radially outward of the wafer W due to centrifugal force, and a resist film is formed on the entire surface of the wafer W. After that, the dripping of the resist solution is stopped, the rotation of the wafer is continued, and the excess resist solution on the surface of the wafer W is shaken off to adjust the film thickness and to perform drying.

In order to form a resist pattern with high precision, it is necessary to form a resist film with a uniform thickness over the entire surface of the wafer. In addition, it is important to strictly control the resist drop time and the timing between the resist drop and wafer rotation.

Conventionally, the film thickness and the film thickness distribution of the resist film have been managed by controlling these by software of the apparatus.

[0006]

However, in the conventional resist liquid supply mechanism, a single resist liquid discharge pump is connected to the resist discharge nozzles of a plurality of resist coating units, and the difference between the head heights and the like is set. Depending on the conditions, there may be a case where the discharge timing of the resist liquid varies depending on the resist liquid discharge nozzle used even in the same recipe. In addition, the discharge timing of the resist liquid also varies due to individual differences in an air operation valve and a resist liquid discharge pump used as an opening / closing valve of the resist liquid supply pipe.
Such a variation in the ejection timing was not so large as to be a problem in the past, but recently, the miniaturization of semiconductor devices and the increase in the diameter of processing substrates have progressed more and more. Since the demand for the uniformity of the film thickness is extremely high, even the variation of the ejection timing due to the head difference and the individual difference described above greatly affects the film thickness and the film thickness uniformity. In recent years, the amount of resist ejection has been reduced (resist saving), and this has also affected variations in ejection amount and changes in ejection speed.

The present invention has been made in view of such circumstances, and provides a coating method and a coating apparatus capable of forming a coating film such as a resist film with high film thickness accuracy and film thickness uniformity. The purpose is to:

[0008]

In order to solve the above-mentioned problems, according to a first aspect of the present invention, a coating liquid is discharged onto a substrate to be processed, and the substrate is rotated so that the diameter of the substrate is reduced. A coating processing method of forming a coating film by spreading outward in a direction, wherein a step of detecting that the discharge of the coating liquid from the coating liquid discharge nozzle is actually started and / or stopped, and And a step of controlling the coating process by using the method.

According to a second aspect of the present invention, there is provided a coating process in which a coating liquid is discharged onto a substrate to be processed and the substrate is rotated to spread the coating liquid radially outward of the substrate to form a coating film. A method of detecting that the discharge of the coating liquid from the coating liquid discharge nozzle has actually started, and driving a pump for discharging the coating liquid from the coating liquid discharge nozzle based on the detection signal. A step of controlling at least one of timing, operation timing of a valve provided in a pipe for supplying a coating liquid to a coating liquid discharge nozzle, and timing of starting or stopping rotation of a substrate to be processed. Provide a processing method.

According to a third aspect of the present invention, there is provided a coating process in which a coating liquid is discharged onto a substrate to be processed and the substrate is rotated to spread the coating liquid radially outward of the substrate to form a coating film. A method for detecting that the discharge of the coating liquid from the coating liquid discharge nozzle is actually stopped, and a pump for stopping the discharge of the coating liquid from the coating liquid discharge nozzle based on the detection signal And controlling at least one of the operation stop timing, the operation timing of a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle, and the rotation stop timing of the substrate to be processed. Provided is a coating treatment method.

According to a fourth aspect of the present invention, there is provided a coating process for discharging a coating liquid onto a substrate to be processed and rotating the substrate to spread the coating liquid radially outward of the substrate to form a coating film. An apparatus, comprising: a substrate holding member for holding a substrate to be processed substantially horizontally; a motor for rotating the substrate holding member; and a coating liquid for discharging a coating liquid to the substrate to be processed held by the substrate holding member. A discharge nozzle, a pump for discharging the coating liquid from the coating liquid discharge nozzle, a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle, and a discharge of the coating liquid from the coating liquid discharge nozzle Detection means for optically detecting the start, and a detection signal of the detection means, and a drive timing of a pump for discharging the coating liquid from the coating liquid discharge nozzle based on the detection signal; Providing a coating processing apparatus characterized by comprising a control means for controlling operation timing of the probe, and at least one drive start or stop timing of the motor.

According to a fifth aspect of the present invention, there is provided a coating process for discharging a coating liquid onto a substrate to be processed and rotating the substrate to spread the coating liquid radially outward of the substrate to form a coating film. An apparatus, comprising: a substrate holding member for holding a substrate to be processed substantially horizontally; a motor for rotating the substrate holding member; and a coating liquid for discharging a coating liquid to the substrate to be processed held by the substrate holding member. A discharge nozzle, a pump for discharging the coating liquid from the coating liquid discharge nozzle, a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle, and a discharge of the coating liquid from the coating liquid discharge nozzle Detection means for optically detecting the end, and a detection signal of the detection means, and a pump stop timing for stopping the discharge of the coating liquid from the coating liquid discharge nozzle based on the detection signal Provides a coating apparatus characterized by a control means for controlling at least one operation timing, and stop timing of the motor of the valve.

According to a sixth aspect of the present invention, there is provided a coating process for discharging a coating liquid onto a substrate to be processed and rotating the substrate to spread the coating liquid radially outward of the substrate to form a coating film. A method of actually detecting a start-up state and / or an end-state of discharge of a coating liquid from a coating liquid discharge nozzle, and a discharge start state and / or a discharge state of a coating liquid based on detection data of the detection step. Controlling the operating speed of a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle so that the discharge end state is within an allowable range.

According to a seventh aspect of the present invention, there is provided a coating process for discharging a coating liquid onto a substrate to be processed and rotating the substrate to spread the coating liquid radially outward of the substrate to form a coating film. A method of detecting that a coating liquid is actually being discharged from a coating liquid discharge nozzle, a step of measuring an actual discharge time in which the detection of the coating liquid is detected in the detecting step, and a step of the measuring step Comparing the actual discharge time measured by the method with the set time of the coating liquid discharge, and determining that there is an abnormality when there is a difference between the actual discharge time and the set time of the coating liquid discharge that is equal to or more than an allowable value. I will provide a.

According to an eighth aspect of the present invention, there is provided a substrate holding member for holding a substrate to be processed substantially horizontally, a motor for rotating the substrate holding member, and a coating liquid applied to a substrate to be processed held by the substrate holding member. A coating liquid discharge nozzle for discharging the coating liquid, a pump for discharging the coating liquid from the coating liquid discharge nozzle, a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle, Detecting means for optically detecting a discharge start state and / or a discharge end state of the coating liquid from the nozzle; and a discharge start state and / or a discharge end state of the coating liquid based on data detected by the detection means. Control means for controlling the operation speed of the valve so as to fall within an allowable range.

According to a ninth aspect of the present invention, there is provided a substrate holding member for holding a substrate to be processed substantially horizontally, a motor for rotating the substrate holding member, and a coating liquid applied to the substrate to be processed held by the substrate holding member. A coating liquid discharge nozzle for discharging the coating liquid; a pump for discharging the coating liquid from the coating liquid discharge nozzle; a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle; A detecting unit for optically detecting that the application liquid is being discharged from the liquid discharge nozzle, a timer for measuring an actual discharge time in which the detection of the application liquid is detected by the detection unit, and a timer for measuring the actual discharge time. A coating processing apparatus comprising: a control unit that compares an actual discharge time with a set time of a coating liquid discharge, and determines that there is an abnormality when there is a difference between the set times and an allowable value or more. That.

According to the first aspect of the present invention, it is detected that the discharge of the coating liquid from the coating liquid discharge nozzle is actually started and / or stopped, and the coating process is controlled based on the detection signal. Therefore, various conditions can be controlled after grasping the time when the application liquid is actually discharged, and a coating film such as a resist film can be formed with high film thickness accuracy and film thickness uniformity.

That is, in the conventional software control, the control for discharging the coating liquid such as the resist liquid is merely to transmit the open signal to the valve provided in the nozzle. The time from when the signal is transmitted to when the resist solution is actually discharged varies due to differences in the head of the resist solution discharge nozzle, individual differences in the pump or valve, etc. Occurs. Therefore, in the present invention, by detecting the actual start and / or stop of the application liquid ejection, the application liquid ejection timing can be controlled with high precision, and the coating film can be formed with high film thickness accuracy and film thickness uniformity. can do.

Specifically, as described in the second and fourth aspects, it is detected that the application liquid is actually started to be discharged from the coating liquid discharge nozzle, and based on the detection signal, At least one of drive timing of a pump for discharging the coating liquid from the coating liquid discharge nozzle, operation timing of a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle, and timing of starting or stopping rotation of the substrate to be processed. By controlling one of them, it is possible to prevent inconveniences such as an excessively high rotation speed of the substrate to be processed at the time when the application liquid is discharged and a short actual discharge time, which cause a change in film thickness.

In this case, a delay time from a timing at which the coating liquid is actually discharged is obtained based on a detection signal indicating that the discharge of the coating liquid has started, and the coating liquid is discharged from the coating liquid discharge nozzle based on the delay time. At least one of the following: a drive timing of a pump, an operation timing of a valve provided in a pipe for supplying a coating liquid to a coating liquid discharge nozzle, and a rotation start or stop timing of a substrate to be processed. .

Further, as in the third and fifth aspects, it is detected that the discharge of the coating liquid from the coating liquid discharging nozzle is actually stopped, and based on the detection signal, the coating liquid discharging nozzle is detected. Controls at least one of the drive stop timing of the pump for stopping the discharge of the coating liquid from the nozzle, the operation timing of the valve provided on the pipe for supplying the coating liquid to the coating liquid discharge nozzle, and the rotation stop timing of the substrate to be processed. By doing so, the actual discharge time of the coating liquid can be more strictly controlled, and the film thickness accuracy and the film thickness uniformity of the coating film can be further increased.

In this case, it is detected that the discharge of the coating liquid from the coating liquid discharge nozzle is actually started, and a delay time from a timing to be actually discharged is obtained based on the detection signal. The timing for stopping the driving of the pump for stopping the discharge of the coating liquid from the coating liquid discharge nozzle, the operation timing of the valve provided on the pipe for supplying the coating liquid to the coating liquid discharge nozzle, and the timing for stopping the rotation of the substrate to be processed At least one can be controlled.

The start or stop of the application liquid discharge can be detected by optical detection means, for example, an optical sensor. As such an optical sensor, an optical sensor having a light emitting optical fiber sensor and a light receiving optical fiber sensor is preferable because it is easy to handle. Further, a CCD camera can be used as an optical detecting means used for the detection. The detection that the discharge of the coating liquid has started or stopped can be performed when the coating liquid is discharged from the coating liquid discharge nozzle to the substrate to be processed, or the coating liquid discharge nozzle is retracted from the substrate to be processed. This can be performed when the application liquid is discharged at the position.

According to the sixth and eighth aspects, the state of actually starting and / or ending the discharge of the coating liquid from the coating liquid discharge nozzle is detected, and the discharge of the coating liquid is started based on the detected data. The operation speed of the valve provided on the pipe for supplying the coating liquid to the coating liquid discharge nozzle is controlled so that the state and / or the discharge end state are within an allowable range. Can be set in advance within an allowable range, so that the state at the start and / or end of the discharge of the coating liquid does not adversely affect the film thickness accuracy and the film thickness uniformity of the coating liquid. You.

According to the seventh and ninth aspects, it is detected that the coating liquid is actually being discharged from the coating liquid discharge nozzle, and the detected actual discharge time is measured. Is compared with the set time of the application liquid discharge, and if there is a difference between the two that is greater than the allowable value, it is determined that there is an abnormality. Abnormality of the application liquid, such as when the application is not stopped, can be grasped.

[0026]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a schematic plan view showing a resist coating and developing processing system including a resist coating processing unit which is an embodiment of the coating processing apparatus of the present invention, FIG.
FIG. 3 is a rear view thereof.

This resist coating and developing processing system 1
A cassette station 11 which is a transfer station;
A processing station 12 having a plurality of processing units;
Exposure apparatus 1 provided adjacent to processing station 12
And an interface station 13 for transferring the wafer W between the processing station 4 and the processing station 12.

A wafer cassette (CR) containing a plurality of (for example, 25) wafers W to be processed in the resist coating / developing processing system 1 is carried into the cassette station 11 from another system. Conversely, a wafer cassette (CR) in which the wafer W that has been processed in the resist coating / developing processing system 1 is stored is carried out from the cassette station 11 to another system. Further, the cassette station 11 has a wafer cassette (CR).
The transfer of the wafer W between the wafer W and the processing station 12 is performed.

In the cassette station 11, as shown in FIG. 1, a plurality of (five in FIG. 1) positioning projections 20a are formed in a row on the cassette mounting table 20 in the X direction. The wafer cassette (CR) has the projection 20a with the wafer loading / unloading port facing the processing station 12 side.
It can be placed at the position. In the wafer cassette (CR), the wafers W are arranged in a horizontal posture and substantially parallel to a vertical direction (Z direction) (see FIGS. 2 and 3).

In the cassette station 11, a wafer transfer mechanism 21 includes a cassette mounting table 20 and a processing station 1.
2 is provided. The wafer transfer mechanism 21 has a wafer transfer pick 21a that can move in the cassette arrangement direction (X direction) and the arrangement direction (Z direction) of the wafers W in the wafer cassette (CR). The pick 21a is rotatable in the θ direction shown in FIG. In this manner, the wafer transfer pick 21a can selectively access any one of the wafer cassettes (CR), and can access a transition unit (TRS-G3) provided in a third processing unit group G3 of the processing station 12 described later. You have access to it.

In the processing station 12, a third processing unit group G3 and a fourth processing unit group G4 are sequentially arranged from the cassette station 11 side on the back side of the system (upper part in FIG. 1).
And a fifth processing unit group G5. A first main transport unit A1 is provided between the third processing unit group G3 and the fourth processing unit group G4, and a second main transport unit is provided between the fourth processing unit group G4 and the fifth processing unit group G5. A
Two are provided. Further on the front side of the system (lower in Fig. 1)
A first processing unit group G1 and a second processing unit group G2 are provided in this order from the cassette station 11 side.

As shown in FIG. 3, the third processing unit group G
In 3, an oven-type processing unit that performs a predetermined process by placing the wafer W on a mounting table, for example, a high-temperature heat treatment unit (BAKE) that performs a predetermined heating process on the wafer W, High-precision temperature control unit (CPL-G3) for performing heat treatment, temperature control unit (TCP),
Transition units (TRS-G3) serving as transfer units for the wafers W between the cassette station 11 and the first main transfer unit A1 are stacked, for example, in ten stages.
In the third processing unit group G3, a spare space is provided in the third row from the bottom, so that a desired oven-type processing unit or the like can be provided.

The fourth processing unit group G4 includes, for example, a pre-bake unit (PAB) for heating the wafer W after resist application, a post-bake unit (POST) for heating the wafer W after development, Temperature control units (CPL-G4) are stacked, for example, in ten stages. In the fifth processing unit group G5, for example, a post-exposure bake unit (PEB) for performing a heat treatment on the wafer W after exposure and before development, and a high-precision temperature control unit (C
PL-G5) are stacked, for example, in ten stages.

As shown in FIGS. 1 and 3, an adhesion unit (AD) is provided on the back side of the first main transport section A1.
And a sixth processing unit group G6 having a heating unit (HP) for heating the wafer W. here,
The adhesion unit (AD) may have a mechanism for controlling the temperature of the wafer W.

On the back side of the second main transfer section A2, the wafer W
Edge exposure device (WE) for selectively exposing only the edge portion of
E) and a film thickness measuring device (FT) for measuring the resist film thickness
7) is provided. Here, the peripheral exposure apparatuses (WEE) may be arranged in multiple stages. A heating unit (HP) is provided on the back side of the second main transport section A2, similarly to the back side of the first main transport section A1.
And other heat treatment units.

As shown in FIGS. 1 and 2, in the first processing unit group G1, five spinners as a liquid supply unit for performing a predetermined processing by placing the wafer W on the spin chuck SP in the cup (CP). Mold processing unit, for example, 3
One resist coating unit (COT) and a bottom coating unit (BARC) for forming an antireflection film for preventing reflection of light during exposure are stacked in a total of five stages. In the second processing unit group G2, five spinner type processing units, for example, developing units (DEV) are stacked in five stages.

The first main transfer unit A1 is provided with a first main wafer transfer unit 16, and the first main transfer unit 16
Each unit provided in the first processing unit group G1, the third processing unit group G3, the fourth processing unit group G4, and the sixth processing unit group G6 can be selectively accessed. Further, the second main transfer section A2 is provided with a second main wafer transfer apparatus 17, and the second main wafer transfer apparatus 17
Are the second processing unit group G2 and the fourth processing unit group G
4. Fifth processing unit group G5, seventh processing unit group G7
Each of the units provided can be selectively accessed.

FIG. 4 is a perspective view showing a schematic structure of the first main wafer transfer device 16. The first main wafer transfer device 16 includes:
Three arms 7a (upper) 7b for holding wafer W
(Middle) 7c (lower) and an arm support plate 51 (arm 7) attached to the base end of each of arms 7a to 7c.
a), a base 52 engaged with each arm support plate 51, a support 53 for supporting the base 52 and the like, and a motor (not shown) built in the support 53. And a rotating rod 54 connecting the base 52 and the motor
And a support 55 provided on the first processing unit group G1 and the second processing unit group G2 side and having a sleeve 55a formed in a vertical direction, and slidably engaged with the sleeve 55a,
In addition, it has a flange member 56 connected to the support portion 53 and a lifting mechanism (not shown) for raising and lowering the flange member 56.

A rail (not shown) is laid on the base 52 for each arm support plate 51 in parallel with the longitudinal direction of the base 52, and each arm support plate 51 is slidable along this rail. Has become. Further, when a motor built in the support portion 53 is rotated, the rotating rod 54 rotates, whereby the base 52 can rotate in the XY plane. Further, since the support portion 53 is attached to the flange member 56 that can move in the Z direction, the base 52 can also move in the Z direction.

With such a configuration, the arms 7a to 7c of the first main wafer transfer device 16 move in the X direction, the Y direction, and the Z direction.
The first processing unit group G1, the third processing unit group G3, the fourth processing unit group G4, and the sixth processing unit group G6, as described above. Each is accessible.

At both ends of the base 52, vertical members 59a are provided.
Is attached. The vertical members 59a are provided with a shielding plate 8 between the arms 7a and 7b for shielding radiant heat from both arms, and a bridging member 59b is mounted between the vertical members 59a.
A pair of optical sensors (not shown) are provided at the center of the bridging member 59b and at the tip of the base 52, whereby the presence or absence of the wafer W and the protrusion of the wafer W in each of the arms 7a to 7c are confirmed. It is supposed to be. The second main wafer transfer device 17 has the same structure as the first main wafer transfer device 16.

The wall 57 shown in FIG. 4 is a part of the housing of the second main transport section A2 on the first processing unit group G1 side. The window 57a provided in the wall 57 is for transferring the wafer W to / from each unit provided in the first processing unit group G1. Further, four fans 5 provided at the bottom of the second main transport section A2 are provided.
Reference numeral 8 controls the pressure, temperature, and humidity in the second main transport unit A2.

Between the first processing unit group G1 and the cassette station 11 and between the second processing unit group G2 and the interface station 13, predetermined first processing unit group G1 and second processing unit group G2 are provided. Liquid temperature control pumps 24 and 25 for supplying a processing liquid are provided, and clean air from an air conditioner (not shown) provided outside the resist coating / developing processing system 1 is supplied to the inside of each processing unit group G1 to G5. Duct 2 to supply to
8.29 are provided.

The first processing unit group G1 to the seventh processing unit group G7 can be removed for maintenance, and the panel on the back side of the processing station 12 can be removed or opened and closed. A chemical unit (C) that supplies a predetermined processing liquid to the first processing unit group G1 and the second processing unit group G2 is provided at the bottom of each of the first processing unit group G1 and the second processing unit group G2.
HM) 26 and 27 are provided. A centralized control section 19 for controlling the entire resist coating / developing processing system 1 is provided below the cassette station 11.

The interface station 13 includes a first interface station 13a on the processing station 12 side and a second interface station 13b on the exposure apparatus 14, and the first interface station 13a has a fifth processing unit group G5. The first wafer carrier 62 is disposed so as to face the opening, and a second wafer carrier 63 movable in the X direction is disposed at the second interface station 13b.

On the back side of the first wafer carrier 62, in order from the top, a peripheral exposure device (WEE), an in-buffer cassette (INBR) for temporarily storing the wafer W transferred to the exposure device 14, and an exposure device 14. Buffer cassette (OUTBR) for temporarily storing wafers W unloaded from
Are stacked in an eighth processing unit group G8. The buffer cassette for IN (INBR) and the buffer cassette for OUT (OUTBR)
Can be accommodated in 25 sheets. On the front side of the first wafer transfer body 62, a transition unit (TRS-G9) and a ninth processing unit group G9 in which a two-stage high-precision temperature control unit (CPL-G9) are stacked in order from the top. Is arranged.

The first wafer transfer body 62 has a wafer transfer fork 62a movable in the Z direction and rotatable in the θ direction, and movable back and forth in the XY plane. The fork 62a is connected to the fifth processing unit group G
5, eighth processing unit group G8, ninth processing unit group G9
Can be accessed, whereby the wafer W can be transferred between the units.

The second wafer carrier 63 moves in the X and Z directions.
And a wafer transfer fork 63a that can move in the direction and rotate in the θ direction and that can move back and forth in the XY plane. This fork 63
a denotes each unit of the ninth processing unit group G9, and the in-stage 14a and the out-stage 14 of the exposure apparatus 14.
b can be accessed, and the wafer W can be transferred between these units.

In the resist coating / developing processing system 1 configured as described above, the wafers W before processing are taken out of the wafer cassette (CR) one by one by the wafer transfer mechanism 21 and the wafers W are transferred to the transition unit (T).
RS-G3). Next, the wafer W is subjected to a temperature control process by a temperature control unit (TCP), and then an antireflection film is formed by a bottom coating unit (BARC) belonging to the first processing unit group G1, and a heating unit (H) is formed.
P) heat treatment unit, high temperature heat treatment unit (BAK
The baking process in E) is performed. Before the anti-reflection film is formed on the wafer W by the bottom coating unit (BARC), the adhesion processing may be performed by the adhesion unit (AD). Further, the adhesion processing may be performed by an adhesion unit (AD) without forming the antireflection film. Next, after the temperature of the wafer W is controlled by the high-precision temperature control unit (CPL-G4), the wafer W is transferred to the resist coating unit (COT) belonging to the first processing unit group G1, and then the coating process of the resist liquid is performed. Do. Thereafter, the wafer W is subjected to a pre-bake process by a pre-bake unit (PAB) provided in the fourth processing unit group G4, and a peripheral exposure process is performed by a peripheral exposure device (WEE), and then a high-precision temperature control unit (CPL-G9). ) And so on. Thereafter, the wafer W is transferred into the exposure device 14 by the second wafer transfer body 63. The wafer W subjected to the exposure processing by the exposure device 14 is carried into the transition unit (TRS-G9) by the second wafer carrier 63, and
The wafer carrier 62 allows the post-exposure bake unit (PE) belonging to the fifth processing unit group G5.
B), a post-exposure bake process is performed, and a developing unit (D) belonging to the second processing unit group G2 is further processed.
EV), and after being subjected to a development process, a post-bake process is performed by a post-bake unit (POST), and a temperature control process is performed by a high-precision temperature control unit (CPL-G3).
The wafer is transferred to a predetermined position of the wafer cassette (CR) in the cassette station 11 via the transition unit (TRS-G3).

Next, a resist coating unit (COT) according to an embodiment of the present invention will be described with reference to FIGS.

This resist coating unit (COT)
Has a casing 70 having an opening 70a into which the arms 7a to 7c of the main wafer transfer device 16 can enter, in which a cup CP, which is a container for accommodating the wafer W, is provided. A spin chuck 71 for holding W horizontally by vacuum suction is provided.
The spin chuck 71 is rotatable by a drive motor 72 such as a pulse motor provided below the cup CP, and its rotation speed can be arbitrarily controlled. An exhaust pipe 73 is connected to a portion near the center of the bottom of the cup CP, and a drain pipe 74 is
Is connected. And, from the exhaust pipe 73, the cup CP
The gas inside is exhausted, and the resist liquid and the solvent scattered during the coating process are exhausted from the drain pipe 74. The spin chuck 71 can be moved up and down by a lifting mechanism such as an air cylinder (not shown).

A jet head 80 is provided above the spin chuck 71 so as to be movable between a position immediately above the spin chuck 71 and a retracted position. The jet head 80 is connected to a drive mechanism 83 via an arm 81. The drive mechanism 83 is moved in the X, Y, and Z directions shown in FIGS. The spout 80 is attached to the arm 8
1 is detachable.

The jet head 80 has a base member 82 and a solvent discharge nozzle 85 for supplying a solvent in which the resist solution can be dissolved.
And a resist solution discharge nozzle 90 for supplying a resist solution as a coating solution. The solvent in which the resist solution can be dissolved is intended to improve the wettability of the resist solution and reduce the consumption of the resist, and may be the solvent of the resist solution, but is not limited thereto and can dissolve the resist coating solution. Any material may be used, and a thinner is typically used.

The jet head 80 has a resist liquid discharge nozzle 90
A pipe (not shown) for circulating a temperature control fluid for controlling the temperature so that the temperature of the resist solution discharged from the nozzle becomes constant, and the temperature of the solvent discharged from the solvent discharge nozzle 85 is maintained constant. There is provided a pipe (not shown) for circulating a temperature control fluid in order to control the temperature.

A resist liquid supply pipe 91 is connected to the resist liquid discharge nozzle 90 and the resist liquid supply pipe 9 is connected to the resist liquid supply pipe 91.
Numeral 1 is connected to a resist solution tank 92 for storing a resist solution. The resist solution supply pipe 91 has a suck back valve 93, an air operation valve 94, and a bubble removing mechanism 9 for separating and removing bubbles in the resist solution.
5. A filter 96 and a pump 97 are provided in that order from the downstream side. As the pump 97, a bellows pump having an expandable and contractable bellows and a tube flam pump having a tube flam which contracts by the pressure of the liquid and sends out the resist liquid can be suitably used. A solvent supply pipe 86 is connected to the solvent discharge nozzle 85, and a solvent supplied from a solvent supply source (not shown) through the solvent supply pipe 86 is discharged from the solvent discharge nozzle 85.

As shown in FIG. 6, a holding portion 75 capable of holding four jet heads 80 having basically the same structure is provided on an outer portion of the cup CP in the casing 70. The holding portion 75 is provided with an insertion portion (solvent drain portion) for placing the nozzle port of each nozzle in a solvent atmosphere so that the nozzle port of each nozzle is not dried and solidified. Each jetting head 80 can be attached to the tip of an arm 81 by an attaching portion 76, and supplies different types of resist liquids. And
One of them is attached to the arm 81 and taken out from the holding section 75. As described above, the arm 81 can be three-dimensionally moved, that is, moved in the X, Y, and Z directions by the driving mechanism 83, and the ejection head 80 taken out of the holding unit 75 and mounted on the arm 81 is used for processing. The wafer is moved to a predetermined position immediately above the wafer W.

In the example shown in FIG. 6, the solvent discharge nozzle 85 and the resist liquid discharge nozzle 90 are attached to each of the jet heads 80. However, the present invention is not limited to this, and only the resist liquid discharge nozzle 90 is attached to each of the jet heads 80. , Solvent discharge nozzle 85
May be provided in common to the resist liquid discharge nozzles 90 of the jet head 80. In this case, the solvent discharge nozzle 8
Alternatively, a driving arm may be provided separately, or the solvent ejection nozzle 85 may be attached to the arm 81 in advance, and may be configured to move integrally with one selected jetting head 80.

The resist coating unit (COT) according to this embodiment has an optical fiber sensor device 100. The optical fiber sensor device 100 includes a light emitting optical fiber sensor 101 attached to a solvent discharge nozzle 85, a light receiving optical fiber sensor 102 attached to a mounting bracket 87 provided downward at the center of an arm 81, and A light source 103 to which the light emitting optical fiber sensor 101 is connected, an amplifier 104 for amplifying the light received by the light receiving optical fiber sensor 102, and a sensor controller for controlling the entire optical fiber sensor device, such as signal processing of the received light. 105. Optical fiber sensor for floodlight 1
No. 01 emits light so as to cross the discharge flow of the resist liquid when the resist liquid is discharged from the resist liquid discharge nozzle 90. Optical fiber sensor 102 for receiving light
Receives light reflected from the wafer W after being emitted from the light emitting optical fiber sensor 101. Since the amount of light detected by the optical fiber sensor 102 for light reception is different between the case where the resist solution is discharged from the resist solution discharge nozzle 90 and the case where the resist solution is not discharged, it is necessary to detect the start of discharge of the resist solution by the optical fiber sensor device 100. Can be.

The resist coating unit (COT) according to this embodiment has a controller 110 (see FIG. 5). The controller 110 includes a drive motor 72 for rotating the spin chuck 71, an air operation valve 94, And the pump 97 can be controlled. A setting device 111 for setting control conditions and the like in the controller 110 is connected to the controller 110. Further, a sensor controller 105 is connected to the controller 110, and the optical fiber sensor device 10 is connected to the sensor controller 105.
0 and a signal from the optical fiber sensor device 100 is received.

When the optical fiber sensor device 100 detects that the resist liquid has been discharged from the resist liquid discharge nozzle 90, this detection signal is guided to the controller 110, and the controller 110 generates a resist based on the signal. The liquid discharge timing is calculated, and at least one of the drive motor 72 for rotating the spin chuck 71, the air operation valve 94, and the pump 97 is controlled based on the calculated resist liquid discharge timing. This makes it important for resist solution application.
The timing of the rotation of the wafer W and the discharge of the resist liquid and the discharge time of the resist liquid are appropriately controlled. In this case,
The controller 110 may automatically control based on the calculated resist solution discharge timing,
The operator may set the parameters of the setting device 111 based on the grasped resist solution discharge timing.

The light projecting optical fiber sensor 101 and the light receiving optical fiber sensor 102 of the optical fiber sensor device 100 may be provided in a cup CP as shown in FIG. In this case, the light emitting optical fiber sensor 1
The light emitted from the optical fiber 01 can reach the light-receiving optical fiber sensor 102 without being reflected on the wafer W.

The optical fiber sensor device 100
As described above, the timing of discharging the resist liquid may be detected not only at the time of actual discharge to the wafer W but also at the time of dummy dispensing without the wafer W. FIG.
As shown in the figure, the drain case 12 in the solvent drain portion 120 of the holding portion 75 on the outer portion of the cup CP.
1 may be provided with an optical fiber sensor 101 for light projection and an optical fiber sensor 102 for light reception, and the timing of discharging the resist liquid may be detected at the time of dummy dispensing there.

In the example of FIG. 5, since the reflected light is difficult to reach the light receiving optical fiber sensor 102 after the resist liquid is discharged, the detection of the start of the resist liquid is limited. However, in the examples of FIGS. , Optical fiber sensor device 10
A value of 0 has no such restriction, so that it is possible to detect not only the start of the discharge of the resist liquid but also the stop of the discharge of the resist liquid. In this case, the controller 110 determines the drive stop timing of the pump 97, the operation timing of the air operation valve 94, and the drive motor 7 based on the detection signal.
It is also possible to control at least one of the second rotation stop timings.

The controller 110 actually controls other members related to the resist coating process, such as the suck back valve 93 and a solvent supply system (not shown), but the description is omitted here. After sucking the resist solution from the resist solution discharging nozzle 90, the suck back valve 93 pulls the resist solution remaining on the inner wall of the tip of the resist solution discharging nozzle 90 due to surface tension back into the resist solution discharging nozzle 90. This prevents the remaining resist solution from solidifying.

Next, the operation and control of the resist coating process in the resist coating unit (COT) configured as described above will be described with reference to the flowchart of FIG.

Arm 7 of first main wafer transfer device 16
a, 7b, or 7c, through an opening 70a of the casing 70, a resist coating unit (COT)
When the wafer W is transported to a position directly above the inner cup CP, the wafer W is vacuum-sucked by the spin chuck 71 that has been lifted by a lifting mechanism (not shown). The main wafer transfer mechanism 22 vacuum-adsorbs the wafer W to the spin chuck 71, then pulls back the arm from the inside of the resist coating unit (COT), and completes the transfer of the wafer W to the resist coating unit (COT) (STEP).
1).

Next, the spin chuck 71 is lowered until the wafer W reaches a fixed position in the cup CP.
The wafer W is rotated at a rotation speed of about m to make the temperature of the wafer W uniform (STEP 2).

Thereafter, the rotation of the spin chuck 71 is stopped, and the ejection head 80 is moved by the driving mechanism 83 in the Y direction to a position immediately above the wafer W, so that the solvent ejection nozzle 85
When the discharge port reaches a position substantially above the center of the spin chuck 71 (substantially the center of the wafer W), a solvent such as a thinner for dissolving the resist is supplied to the substantially center of the surface of the stationary wafer W, and is preferably 1000 rpm or less. A pre-wet process is performed in which the wafer W is rotated at a predetermined rotation speed to spread the solvent supplied to the surface of the wafer W over the entire surface of the wafer W (S
TEP3). This improves the wettability of the resist solution,
The amount of the resist discharged onto the wafer W can be reduced.

Subsequently, the jet head 80 is moved by the driving mechanism 83 in the Y direction until the discharge port of the resist liquid discharge nozzle 90 reaches a position substantially above the center of the spin chuck 71 (substantially the center of the wafer W). By increasing the speed to a predetermined value, the resist liquid is supplied from the discharge port of the resist liquid discharge nozzle 90 to substantially the center of the surface of the rotating wafer W, and the resist liquid is diffused outward by centrifugal force, and A resist coating process is performed (STEP 4). In this resist coating process, first, the resist solution is rotated at a relatively high speed while discharging the resist solution in order to spread the resist solution. The rotation speed at this time is 2000 for a 200 mm wafer.
6000 rpm, 100 for 300 mm wafer
It is preferably from 0 to 4000 rpm. Thereafter, the supply of the resist liquid is stopped, and the rotation speed of the wafer W is reduced. As a result, the film thickness adjusting function is exhibited, and the wafer W
Uniformity of in-plane film thickness is promoted. This effect is obtained because when the rotation speed of the wafer W is reduced, a force toward the center acts on the resist solution on the semiconductor wafer W due to the acceleration at the time of the reduction, and furthermore, the processing target substrate This is because the low-speed rotation slows down the drying of the resist solution, and as a result, a function of adjusting the film thickness is exhibited. That is, due to the inward force acting by this deceleration,
The amount of the resist scattered to the outside of the wafer W is suppressed, and the resist is held on the outer peripheral portion as in the central portion, so that the thickness of the resist film becomes more uniform. The rotation speed at this time is preferably 50 to 1000 rpm. In particular, 500 rpm
If it is less than the above, the drying of the resist hardly proceeds, and the degree of freedom of the film thickness adjustment is high. The holding time at this time is, for example,
The time is set to an appropriate time up to 3 seconds. Note that the rotation deceleration at this time is not essential, and is performed as necessary.

Thereafter, the rotation speed of the wafer W is increased to shake off the remaining resist solution (STEP 5). The rotation speed at this time is 1500 for a 200 mm wafer.
Up to 4000 rpm, 100 for 300 mm wafers
It is preferably from 0 to 3000 rpm.

Thereafter, the rotation of the wafer W is continued to dry the resist film (STEP 6). The rotation speed at this time is 1000 to 2000 r for a 200 mm wafer.
pm, 500 to 1500r for 300mm wafer
pm. After performing this step for a predetermined time, the resist coating step is completed.

Next, the control during the resist coating process will be described in detail.

At the time of applying the resist solution, the rotation of the drive motor 72, the operation of the pump 97, and the air as the opening / closing valve are conventionally performed by software in order to form the resist film with high film thickness accuracy and film thickness uniformity. The operation of the operation valve 94 is strictly controlled. FIG. 10 shows the ideal timing of these operations when the resist liquid is applied by the conventional control, and the timing of discharging the resist liquid at that time. First, from the controller 110,
A drive start signal is sent to the drive motor 72, a discharge operation start signal is sent to the pump 97, and an open signal is sent to the air operation valve 94 at the same time. Thereby, the rotation of the spin chuck 71 is started, and the rotation speed is increased. The pump 97 discharges the resist liquid almost simultaneously with the command from the controller 110, the air operation valve 94 is opened with a slight delay, and immediately after that, the discharge of the resist liquid is started. The timing at which the resist solution is discharged at this time is adjusted so that the wafer W rotating with the spin chuck 71 is still rotating at a low speed. And FIG.
As shown in the figure, after the lapse of the discharge time t0 on the signal, the discharge operation end signal is sent from the controller 110 to the pump 97 and the close signal is sent to the air operation valve 94 at the same time. The drive stop signal is sent to the drive motor 72 so that the valve 94 is actually closed and the rotation of the wafer W is reduced at that time. In this case, the air operation valve 94
The opening time t1 and the actual ejection time t2 substantially coincide with the ejection time t0 on the signal, and no problem occurs.

However, the resist coating units (COT) are stacked in three stages as described above, and the resist solution is usually supplied to the resist solution discharge nozzle 90 of each unit through a common pipe. Due to the head difference between the pumps and the individual differences in the pump or the air operation valve, etc., from when the controller 110 sends an open signal to the air operation valve 94 until the resist liquid is started to be discharged from the resist liquid discharge nozzle 90. As shown in FIG. 11, the time from the opening of the air operation valve 94 to the discharge of the resist solution is delayed from the ideal state shown in FIG. 10, and the delay time Δt is increased. At the time when the liquid discharge is started, if the rotational speed of the wafer W reaches or reaches the maximum speed. There is. When the resist liquid is discharged in a state where the rotation speed of the wafer W is high, the thickness of the resist film greatly deviates from a set value. In this case, the actual discharge time t2 'of the resist liquid is shorter than t2 by the delay of the start of discharge of the resist liquid. However, as the delay time Δt becomes longer and the discharge time becomes shorter, the film around the wafer W becomes shorter. As the thickness becomes thin, the uniformity of the resist film thickness deteriorates.

In order to avoid such a problem, as described above, the start of discharge of the resist solution is detected by the optical fiber sensor device 100, and the resist solution discharge start timing calculated based on the signal is used. The coating process is controlled.

More specifically, the controller 110 starts the drive start timing of the drive motor 72 for rotating the spin chuck 71 and the air operation valve 94 based on the resist solution discharge start timing calculated from the detection signal from the optical fiber sensor device 100. , And at least one of the drive timings of the pump 97 is controlled. For example, as shown in FIG. 12, the resist solution discharge start timing is calculated based on the detection signal of the optical fiber sensor device 100, and the controller 110 is controlled based on the calculated value at the time of the next wafer resist solution coating process. Delays the drive start timing of the drive motor 72. Of course, the drive start timing of the pump 97 and / or the opening operation timing of the air operation valve 94 may be advanced. Further, the controller 110 calculates a delay time Δt from the resist liquid discharge start signal, and sends a control signal to the pump 97 and the air operation valve 94 so as to extend the resist liquid discharge time by a time corresponding to the delay time Δt. To make the actual discharge time t2 ″ of the resist liquid substantially equal to t2. Based on this, the stop timing of the drive motor 72 is also controlled.

As described above, the fact that the resist liquid is actually started to be discharged from the resist liquid discharge nozzle 90 is detected, and the coating process of the resist liquid is controlled based on the detection signal. The various conditions can be controlled after grasping the
The resist film can be formed with high film thickness accuracy and film thickness uniformity by compensating for variations in the timing of starting the discharge of the resist solution due to differences in the heads of the pump and individual differences in the pump 97 or the air operation valve 94.

Specifically, the optical fiber sensor device 1
00, the start of discharge of the resist liquid from the resist liquid supply nozzle 90 is detected, and the drive start timing of the drive motor 72 for rotating the spin chuck 71 and the air Since at least one of the drive timing of the operation valve 94 and the drive timing of the pump 97 is controlled, the rotation speed of the wafer W is too high at the time when the resist liquid is discharged, and the thickness of the resist film does not reach a predetermined thickness. Can be prevented. Further, a delay time Δt from when the opening signal is transmitted to the air operation valve 94 from the signal that has detected the start of discharge of the resist liquid to when the resist liquid is actually discharged is calculated. Is controlled so that the discharge time of the resist solution is extended to a specified time, so that the actual discharge time of the resist solution can be made substantially constant, and the uniformity of the film thickness of the resist film can be further improved. it can. At this time, the stop timing of the drive motor 72 is also controlled based on the delay time Δt.
This can further improve the uniformity of the thickness of the resist film.

On the other hand, after the closing signal is transmitted to the air operation valve 94, the resist solution discharge nozzle 90 is actually
There is also a possibility that the time until the discharge of the resist solution from the substrate is stopped varies due to various factors. As described above, when the time until the resist liquid discharge is stopped varies, even if the actual discharge time of the resist liquid is controlled based on the resist liquid discharge start signal as described above, the actual discharge time actually varies. I will.

In such a case, it is detected by the optical fiber sensor device 100 that the discharge of the resist solution has been stopped, and based on this, the drive stop timing of the pump 97, the operation timing of the air operation valve 94, and the drive motor 72 At least one of the rotation stop timings is controlled. As a result, such a variation in the actual ejection time can be significantly reduced. Specifically, the controller 110 calculates the resist liquid discharge stop timing based on the discharge stop detection signal of the optical fiber sensor device 100, and based on the calculated value at the time of the next wafer resist liquid coating processing. At least one of the drive stop timing of the pump 97, the operation timing of the air operation valve 94, and the rotation stop timing of the drive motor 72 is controlled so that the discharge of the resist is stopped at an appropriate timing.

However, as described above, in the case of FIG.
Since it is not possible to detect the stop of the discharge of the resist solution,
Detection of such a stoppage of the discharge of the resist solution is shown in FIGS.
Is limited to the case where the optical fiber sensor device 100 is attached as shown in FIG.

With the above control, the discharge start timing and the actual discharge time of the resist solution can be controlled with high accuracy. In addition to the above control using the above-described optical fiber sensor device 100, or Apart from the above control, the following method can also contribute to high film thickness accuracy and film thickness uniformity. First, in the first method, the optical fiber sensor device 100
The state at the time of starting the discharge of the resist liquid and / or the state at the time of stopping the discharge are detected, and the air operation valve 9 is detected.
Control the opening and / or closing speed of 4 to an acceptable range.
Specifically, if the opening speed of the air operation valve 94 is too fast, for example, the resist liquid is once drawn in and then discharged, and if it is too slow, for example, the dripping occurs. If the closing speed of the air operation valve 94 is too fast, the state of stopping the discharge of the resist solution becomes unstable, and if it is too slow, dripping occurs. Therefore, the opening speed and / or the closing speed of the air operation valve 94 are adjusted in advance so that the state at the time of starting and / or stopping the discharge of the resist liquid is within an allowable range.

As shown in FIG. 13, for example, the air operation valve 94 includes a container 121, a valve body 122 provided in the container 121 so as to be able to move up and down, a valve seat 123 below the valve body 122, And a part 124. The resist liquid flow section 124 has a resist liquid flow path 125 connected to the resist liquid supply pipe 91.
26 and the resist solution outlet 127 are open. Then, the flow of the resist liquid is shut off when the valve body 122 is in contact with the valve seat 123 and the resist liquid flows when the valve body 122 is open and separated from the valve seat 123. A partition member 128 for vertically partitioning the inside of the container 121 is provided so as to be able to move up and down, and the valve body 122 is integrally provided so as to hang from the partition member 128. Then, an air introduction pipe 1 is provided through an air introduction port 129 provided on the side wall of the container 121.
When air is introduced into the container 121 through the partition 30, the partition member 128 moves upward, and accordingly, the valve body 122 moves upward, so that the valve 94 is opened. The introduction of air at that time is performed by operating an introduction-side solenoid valve 132 provided in the air introduction pipe 130. The container 121 has an air outlet 1
An air discharge pipe 135 is connected to the air discharge port 134. When the valve 94 is closed, the supply of air is stopped and a discharge solenoid provided in the air discharge pipe 135 is provided. By operating the valve 136, the air in the container 121 is discharged. A coil spring 131 that urges the partition member 128 downward is provided in an upper portion of the partition member 128 in the container 121, and when the air is not introduced into the container 121 and when the air is discharged as described above. Has an air operation valve 9
4 has a normally closed structure in which the container is closed, and after the air operation valve 94 is opened, the inside of the container 121 is exhausted from the air discharge pipe 135 so that the valve 94 is closed.

The operation of the introduction-side solenoid valve 132 and the discharge-side solenoid valve 136 is performed by a valve controller 140.
Is controlled by the controller 110 described above. Therefore, the speed at which the air operation valve 94 is opened and the speed at which the air operation valve 94 is closed are controlled by the valve controller 140 by controlling the inlet solenoid valve 132 and the discharge solenoid valve 136, respectively, according to a command from the controller 110. This is done by controlling the speed and the discharge speed.

When the speed at which the air operation valve 94 is opened is initially set, the opening of the air operation valve 94 is started at various speeds and the state of starting the discharge of the resist solution at that time is detected by the optical fiber sensor device 100. Automatic speed selection. Then, at the time of actual discharge of the resist solution, the value is used as a set value. Even when the speed at which the air operation valve 94 is closed is initially set, the optical fiber sensor device 100 detects the resist liquid ejection stop state at various speeds by closing at various speeds, and determines the optimum speed among those within the allowable range. Select automatically. Then, when actually discharging the resist solution,
Use that value as the set value. As described above, the state at the start and / or end of the discharge of the resist solution can be set in advance within an allowable range, and the state at the start and / or end of the discharge of the resist solution can be adjusted to the resist film thickness accuracy. In addition, adverse effects on the film thickness uniformity are avoided. In this case, the time (Delay time) from when the signal is sent to the air operation valve 94 to the start and / or the stop of the actual liquid discharge depends on the opening and / or closing speed. After the closing speed is set, the corresponding delay time setting value is determined. In the first method, the optical fiber sensor device 100 may be any one of FIGS. 5, 7 and 8 as long as the discharge start state of the resist liquid is only optimized. Use FIGS. 7 and 8.

Next, the second method will be described. This method is for grasping a discharge abnormality of the resist liquid such that the resist liquid is interrupted on the way or the discharge of the resist liquid is not stopped at the timing of stopping the discharge of the resist liquid. Specifically, as shown in FIG. 14, the actual ejection time when the resist solution ejection is detected by the optical fiber sensor device 100 is determined by the timer 1 connected to the controller 110.
41, the measured actual discharge time is compared with the set time of resist liquid discharge, and if there is a difference between them exceeding an allowable value, it is determined that there is an abnormality. This allows
The process can be stopped in the event of abnormal discharge, and the influence of abnormal discharge of the resist liquid on the accuracy and uniformity of the resist film thickness can be avoided. In the case of the second method, since it is necessary to grasp that actual ejection is performed, the arrangement of the optical fiber sensor device 100 is shown in FIGS.

Next, a resist coating unit (COT) according to another embodiment of the present invention will be described with reference to FIG.

This embodiment differs from the previous embodiment in that a CCD camera system 150 is used instead of the optical fiber sensor device 100 of the previous embodiment as detection means, and is configured similarly to the previous embodiment.

The CCD camera system 150 is a CCD camera for photographing the discharge flow from the resist discharge nozzle 90.
A camera 151; a camera control unit 152 for controlling operation and information of the CCD camera 151;
3 and a monitor 154. CCD camera 1
The image photographed at 51 is transmitted to the image processing unit 153 via the camera control unit 152, where predetermined image processing is performed, and the information is transmitted to the camera control unit 152. The suspension of liquid discharge is recognized. Then, the image at that time is monitored by the monitor 154 as necessary. This makes it possible to detect the actual start of the discharge of the resist solution and / or the stop of the discharge of the resist solution, so that the same control as in the previous embodiment can be performed, and at the time when the resist solution is discharged, Inconveniences such as an excessively high rotation speed and a short actual discharge time, which are factors causing a change in film thickness, are prevented.

The present invention is not limited to the above embodiment, and various modifications are possible. For example, although the case where the optical fiber sensor device and the CCD camera system are used as the detecting means for detecting the start or stop of the discharge of the resist liquid has been described, other optical sensors other than the optical fiber sensor may be used, and other optical sensors may be used. Target detection means can also be used. Although the case where a resist solution is used as a coating solution has been described, the coating solution is not limited to the resist solution, but may be a coating solution for a film formed by performing a spin coating process such as an antireflection film or an interlayer insulating film. It may be a liquid. Furthermore, in the above embodiment, the case where a semiconductor wafer is used as a substrate to be processed has been described. However, the present invention is not limited to the semiconductor wafer, and another substrate to be processed such as an LCD substrate or a reticle substrate for a mask may be used.

[0092]

As described above, according to the present invention,
Since the start and / or the stop of the application liquid ejection from the application liquid ejection nozzle are actually detected, and the application process is controlled based on the detection signal, the time when the application liquid is actually ejected is determined. Thus, various conditions can be controlled, and a coating film such as a resist film can be formed with high film thickness accuracy and film thickness uniformity.

Specifically, it is detected that the discharge of the coating liquid from the coating liquid discharge nozzle is actually started, and a pump for discharging the coating liquid from the coating liquid discharge nozzle is detected based on the detection signal. By controlling at least one of the drive timing, the operation timing of a valve provided in a pipe for supplying a coating liquid to a coating liquid discharge nozzle, and the start or stop timing of rotation of the substrate to be processed, the time when the coating liquid is discharged In this case, it is possible to prevent inconveniences such as an excessively high rotation speed of the substrate to be processed and a short actual discharge time, which may cause a change in film thickness.

Further, it is detected that the discharge of the coating liquid from the coating liquid discharge nozzle has actually been stopped, and based on the detection signal, the driving of the pump for stopping the discharge of the coating liquid from the coating liquid discharge nozzle is performed. By controlling at least one of the stop timing, the operation timing of a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle, and the rotation stop timing of the substrate to be processed, the actual discharge time of the coating liquid is more strict. , And the film thickness accuracy and the film thickness uniformity of the coating film can be further enhanced.

Further, the discharge start state and / or the discharge end state of the coating liquid from the coating liquid discharge nozzle are actually detected, and based on the detected data, the discharge start state and / or the discharge end state of the coating liquid are within an allowable range. The operation speed of the valve provided in the pipe for supplying the coating liquid to the coating liquid discharge nozzle is controlled so that the discharge of the coating liquid can be started and / or
Alternatively, the state at the end of the discharge can be set in advance within an allowable range, and the state at the start and / or the end of the discharge of the coating liquid adversely affects the film thickness accuracy and the film thickness uniformity of the coating liquid. Is avoided.

Further, it is detected that the coating liquid is actually being discharged from the coating liquid discharge nozzle, the detected actual discharge time is measured, and the measured actual discharge time is compared with the set time of the coating liquid discharge. However, if there is a difference between these values that is greater than or equal to the allowable value, it is determined that there is an abnormality. You can figure out.

[Brief description of the drawings]

FIG. 1 is a plan view showing the overall configuration of a semiconductor wafer resist coating and developing processing system equipped with a resist coating processing unit for carrying out the present invention.

FIG. 2 is a front view of the resist coating and developing system shown in FIG.

FIG. 3 is a rear view of the resist coating and developing system shown in FIG. 1;

FIG. 4 is a perspective view illustrating a schematic structure of a main wafer transfer device provided in the resist coating and developing processing system of FIG. 1;

FIG. 5 is a cross-sectional view showing the overall configuration of the resist coating unit according to the embodiment of the present invention, which is mounted on the coating and developing system shown in FIG.

6 is a plan view of the resist coating unit shown in FIG.

FIG. 7 is a cross-sectional view showing another example of the mounting position of the light emitting optical fiber sensor and the light receiving optical fiber sensor in the optical fiber sensor device.

FIG. 8 is a cross-sectional view showing still another example of the mounting position of the light emitting optical fiber sensor and the light receiving optical fiber sensor in the optical fiber sensor device.

FIG. 9 is a process chart showing processing steps in a resist coating processing unit.

FIG. 10 is a graph showing operation timings of a drive motor, a pump, an air operation valve, and ideal timing of resist liquid discharge when resist liquid application is performed by conventional control.

FIG. 11 shows a state in which a resist solution is applied by conventional control.
7 is a graph showing operation timings of a drive motor, a pump, an air operation valve, and a timing of discharging a resist liquid when a discharge delay occurs.

FIG. 12 is a graph showing operation timings of a drive motor, a pump, an air operation valve, and a timing of discharging a resist liquid when a resist liquid is applied under the control of the embodiment of the present invention.

FIG. 13 is a block diagram for explaining a method for performing initial setting of an air operation valve using an optical fiber sensor device.

FIG. 14 is a block diagram for explaining a method for grasping a resist liquid ejection abnormality using an optical fiber sensor device.

FIG. 15 is a cross-sectional view illustrating an overall configuration of a resist coating unit according to another embodiment of the present invention.

FIG. 16 is a schematic configuration diagram of a conventional resist coating apparatus.

[Explanation of symbols]

71: Spin chuck (substrate holding member) 72 Drive motor 80 ... Spout 90 ... resist liquid discharge nozzle 91 ... Resist liquid supply piping 94 …… Air operation valve 97 …… Pump 100 optical fiber sensor device (detection means) 101 Optical fiber sensor for floodlight 102: Optical fiber sensor for receiving light 110 Controller W ... Semiconductor wafer (substrate to be processed)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) G03F 7/16 502 H01L 21/30 564D 564Z (72) Inventor Yoshiteru Fukuda 5-chome Akasaka, Minato-ku, Tokyo No. 6 TBS Broadcasting Center Tokyo Electron Limited (72) Inventor Junya Minamida 3-6 Akasaka, Minato-ku, Tokyo TBS Broadcasting Center Tokyo Electron Limited F-term (reference) 2H025 AA18 AB16 EA05 4D075 AC06 AC64 AC84 AC91 AC93 CA23 CA48 CB02 DA06 DA08 DB13 DB14 DC22 DC24 EA07 EA45 4F041 AA06 AB01 4F042 AA07 BA12 CB02 CB08 DF32 EB13 EB17 5F046 JA01 JA13 JA16

Claims (23)

[Claims] 1. A coating method in which a coating liquid is discharged onto a substrate to be processed and the substrate is rotated, and the coating liquid is spread radially outward of the substrate to form a coating film. A coating method, comprising: detecting a start and / or stop of discharge of a coating liquid from a coating liquid discharge nozzle; and controlling a coating processing based on the detection signal. 2. A coating method for discharging a coating liquid onto a substrate to be processed, rotating the substrate to be processed, and spreading the coating liquid radially outward of the substrate to be processed to form a coating film. A step of detecting that the discharge of the coating liquid from the coating liquid discharge nozzle is started, and, based on the detection signal, a drive timing of a pump for discharging the coating liquid from the coating liquid discharge nozzle; A coating control method comprising: controlling at least one of an operation timing of a valve provided in a pipe for supplying a coating liquid and a rotation start or stop timing of a substrate to be processed. 3. In the control step, a delay time from a timing at which the coating liquid is actually to be discharged is obtained based on a detection signal indicating that the discharge of the coating liquid has been started, and the coating liquid is discharged from the coating liquid discharge nozzle based on the delay time. At least one of a drive timing of a pump for discharging the liquid, an operation timing of a valve provided in a pipe for supplying a coating liquid to a coating liquid discharge nozzle, and a rotation start or stop timing of a substrate to be processed. The coating treatment method according to claim 2, wherein 4. A coating method for discharging a coating liquid onto a substrate to be processed, rotating the substrate to be processed, and spreading the coating liquid radially outward of the substrate to be processed to form a coating film. A step of detecting that the discharge of the coating liquid from the coating liquid discharge nozzle is stopped, and a drive stop timing of a pump for stopping the discharge of the coating liquid from the coating liquid discharge nozzle based on the detection signal; Operation timing of a valve provided in a pipe for supplying a coating liquid to a discharge nozzle,
And a step of controlling at least one of the rotation stop timings of the substrate to be processed. 5. The control step detects that the application liquid is actually ejected from the application liquid ejection nozzle, and obtains a delay time from an actual ejection timing based on the detection signal. On the basis thereof, the drive stop timing of the pump for stopping the discharge of the coating liquid from the coating liquid discharge nozzle, the operation timing of the valve provided on the pipe for supplying the coating liquid to the coating liquid discharge nozzle, and the The coating method according to claim 4, wherein at least one of the rotation stop timings is controlled. 6. The coating method according to claim 1, wherein the detection of the start or stop of the application liquid discharge is performed by an optical sensor. 7. The coating method according to claim 6, wherein the optical sensor includes a light emitting optical fiber sensor and a light receiving optical fiber sensor. 8. The coating process according to claim 1, wherein the detection that the discharge of the coating liquid has started or stopped is performed using a CCD camera. Method. 9. The method according to claim 1, wherein the detection of the start or stop of the discharge of the application liquid is performed when the application liquid is discharged from the coating liquid discharge nozzle to the substrate to be processed.
The coating treatment method according to any one of claims 1 to 8. 10. The method according to claim 1, wherein the detection of the start or stop of the application liquid discharge is performed when the application liquid discharge nozzle discharges the application liquid at a position retracted from the substrate to be processed. The coating treatment method according to any one of claims 1 to 8. 11. A coating processing apparatus for discharging a coating liquid onto a substrate to be processed and rotating the substrate to spread the coating liquid radially outward of the substrate to form a coating film. A substrate holding member for holding the substrate substantially horizontally; a motor for rotating the substrate holding member; a coating liquid discharge nozzle for discharging a coating liquid onto a substrate to be processed held by the substrate holding member; A pump for discharging the coating liquid from the discharge nozzle, a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle, and optically detecting the start of discharge of the coating liquid from the coating liquid discharge nozzle Detection means, a detection signal of the detection means is inputted, and based on the detection signal, a drive timing of a pump for discharging the coating liquid from the coating liquid discharge nozzle, an operation timing of the valve Grayed, and coating treatment apparatus characterized by a control means for controlling at least one drive start or stop timing of the motor. 12. The control unit according to claim 1, wherein the control unit obtains a delay time from a timing at which the coating liquid is actually discharged based on a detection signal of the detection unit, and discharges the coating liquid from the coating liquid discharge nozzle based on the delay time. The coating processing apparatus according to claim 11, wherein at least one of a drive timing of a pump, an operation timing of the valve, and a drive start or stop timing of the motor is controlled. 13. A coating processing apparatus for discharging a coating liquid onto a substrate to be processed and rotating the substrate to spread the coating liquid radially outward of the substrate to form a coating film. A substrate holding member for holding the substrate substantially horizontally; a motor for rotating the substrate holding member; a coating liquid discharge nozzle for discharging a coating liquid onto a substrate to be processed held by the substrate holding member; A pump for discharging the coating liquid from the discharge nozzle, a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle, and optically detecting completion of discharge of the coating liquid from the coating liquid discharge nozzle A detection unit, a detection signal of the detection unit is input, and based on the detection signal, a drive stop timing of a pump for stopping discharge of the coating liquid from the coating liquid discharge nozzle, Create timing, and coating treatment apparatus characterized by a control means for controlling at least one of the stop timing of the motor. 14. The control means calculates a delay time from a timing at which discharge is actually stopped based on a detection signal of the detection means, and discharges the coating liquid from the coating liquid discharge nozzle based on the delay time. 14. The coating processing apparatus according to claim 13, wherein at least one of a drive stop timing of a pump for stopping the operation, an operation timing of the valve, and a stop timing of the motor is controlled. 15. The coating processing apparatus according to claim 11, wherein the detection unit has an optical sensor. 16. The coating apparatus according to claim 15, wherein the optical sensor includes a light emitting optical fiber sensor and a light receiving optical fiber sensor. 17. The coating apparatus according to claim 11, wherein said detection means has a CCD camera. 18. The apparatus according to claim 11, wherein said detecting means performs detection when the application liquid is ejected from the application liquid ejection nozzle onto the substrate to be processed.
The coating treatment apparatus according to the item. 19. The apparatus according to claim 11, wherein said detection means performs detection when the application liquid discharge nozzle discharges the application liquid at a position retracted from the substrate to be processed. The coating treatment apparatus according to the item. 20. A coating method for forming a coating film by discharging a coating liquid onto a substrate to be processed, rotating the substrate to be processed, and spreading the coating liquid radially outward of the substrate to be processed.
A step of actually detecting the start and / or end of discharge of the coating liquid from the coating liquid discharge nozzle, and the start and / or end of discharge of the coating liquid are allowed based on the detection data of the detection step. Controlling the operation speed of a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle so as to fall within the range. 21. A coating method for discharging a coating liquid onto a substrate to be processed, rotating the substrate to be processed, and spreading the coating liquid radially outward of the substrate to be processed to form a coating film.
A step of detecting that the coating liquid is actually being discharged from the coating liquid discharge nozzle; a step of measuring an actual discharge time in which the discharge of the coating liquid is detected in the detecting step; and a step of measuring the actual discharge time. A step of comparing the ejection time with a set time of the application liquid ejection, and judging that there is an abnormality when a difference between them is equal to or more than an allowable value. 22. A substrate holding member for holding a substrate to be processed substantially horizontally, a motor for rotating the substrate holding member, and a coating liquid for discharging a coating liquid to the substrate to be processed held by the substrate holding member. A discharge nozzle, a pump for discharging the coating liquid from the coating liquid discharge nozzle, a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle, and a discharge of the coating liquid from the coating liquid discharge nozzle A detection unit for optically detecting a start state and / or a discharge end state, and based on data detected by the detection unit,
Control means for controlling the operation speed of the valve so that the discharge start state and / or the discharge end state of the coating liquid fall within an allowable range. 23. A substrate holding member for holding a substrate to be processed substantially horizontally, a motor for rotating the substrate holding member, and a coating liquid for discharging a coating liquid to the substrate to be processed held by the substrate holding member. A discharge nozzle, a pump for discharging the coating liquid from the coating liquid discharge nozzle, a valve provided in a pipe for supplying the coating liquid to the coating liquid discharge nozzle, and a coating liquid actually from the coating liquid discharge nozzle Detecting means for optically detecting that the liquid is being discharged, a timer for measuring an actual discharge time when the discharge of the coating liquid is detected by the detecting means, an actual discharge time measured in the measuring step, and a discharge of the coating liquid. And a control means for comparing the set times with each other and determining that there is an abnormality when there is a difference between the set times and an allowable value or more.