JP2002043268A - Substrate processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably maintain the processing quality and efficiency through appropriate management of intensity of the ultraviolet-ray for a substrate to be processed in the ultraviolet-ray irradiation process. SOLUTION: An output signal (for example, a photo-current) of a photo-sensor 104 on a stage 94 is inputted to an illuminance measuring circuit 128. The illuminance measuring circuit 128 obtains a measuring value E of the intensity of the ultraviolet-ray at the surface of a substrate G on the stage 94 using a value of the output signal of the photo-sensor 104, and an offset value (d) of the height position between the photo-sensing surface of the photo-sensor 104 and the surface of the substrate G as the parameters. An illuminance comparator 132 compares the measured value E of the ultraviolet-ray intensity with the reference standard Es from a reference illuminance setting means 134 to obtain a difference, namely an error δE of illuminance. A stage lifting control means 136 drives and controls a stage lifting drive mean 116 so as to approximate such error δE to zero in order to change the substrate supporting height Ha of the stage 94. As a result, variable adjustment of height of the stage is stopped when the ultraviolet-ray illuminance measuring value E obtained from the illuminance measuring circuit 128 matches the reference standard Es.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a substrate processing apparatus for performing predetermined processing by irradiating a substrate to be processed with ultraviolet rays.

[0002]

2. Description of the Related Art In the manufacture of semiconductor devices, various types of fine processing are performed on the premise that a surface of a substrate to be processed (for example, a semiconductor wafer, an LCD substrate, etc.) is in a cleaned state. Therefore, prior to each processing or between each processing, the surface of the substrate to be processed is cleaned,
For example, in a photolithography process, the surface of a substrate to be processed is cleaned before applying a resist.

Conventionally, as a cleaning method for removing organic substances on the surface of a substrate to be processed, a dry cleaning technique using ultraviolet irradiation has been known. This ultraviolet irradiation cleaning technology excites oxygen using ultraviolet light of a predetermined wavelength (185 nm, 254 nm when using a low-pressure mercury lamp as an ultraviolet light source, and 172 nm when using a dielectric barrier discharge lamp) to generate ozone and the generation time. The organic material on the substrate surface is oxidized and vaporized by the oxygen to remove it.

[0004] A typical conventional ultraviolet irradiation type cleaning apparatus is as follows.
A plurality of the lamps serving as the ultraviolet light sources as described above are housed side by side in a lamp chamber having a quartz glass window, and a substrate to be processed is arranged in a cleaning processing chamber adjacent to the lamp chamber through the quartz glass window. UV light emitted from the lamp is irradiated to the surface of the substrate to be processed through the quartz glass window for a certain period of time. In recent years, a mechanism for relatively moving or scanning the lamp in parallel with the surface of the substrate to be processed has also been used to reduce the size of the apparatus (reducing the number of lamps, downsizing the quartz glass window, etc.).

[0005]

In the above-described ultraviolet irradiation type cleaning apparatus, in order to obtain a desired cleaning effect, the illuminance and the amount of ultraviolet light applied to a substrate to be processed by an ultraviolet lamp must be at least a predetermined value. It is necessary to secure them, and specifications of each part of the apparatus are made so as to satisfy such ultraviolet irradiation conditions. However, if the luminance of the ultraviolet lamp decreases with the lapse of time, the illuminance or the amount of ultraviolet light on the substrate to be processed becomes insufficient, and there is a possibility that cleaning failure may occur. However, this type of conventional apparatus does not have a means for accurately measuring the UV illuminance on the substrate to be processed and a means for accurately compensating for the change in the UV illuminance. It was difficult to maintain.

In an apparatus using a dielectric barrier discharge lamp, ultraviolet excimer light having a wavelength of 172 nm emitted from the lamp is very easily absorbed by oxygen, and reaches the surface of a substrate to be processed after exiting a quartz glass window. Exponentially decay as the distance up to is increased. For this reason, it is preferable to make the gap between the two (the quartz glass window and the substrate to be processed) as small as possible. Usually, the distance is set to 3 to 7 mm in consideration of dimensional errors and errors in mechanical accuracy. However, even in such a small gap, the illuminance of the ultraviolet light is greatly attenuated to about a fraction, and the energy efficiency is low.

Further, in this type of apparatus, there is a problem that a reaction product due to ultraviolet rays adheres to the outer surface (surface on the substrate side) of quartz glass. In other words, organic substances and chemicals that adhere or float on or near the surface of the substrate to be processed react with the light energy of ultraviolet rays, and the reaction product adheres to the quartz glass that is in close proximity to the substrate, resulting in a white color. It may become a precipitate, thereby deteriorating the ultraviolet transmission properties of the quartz glass, or peeling off a reaction product or a precipitate from the quartz glass, which may cause particles.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and is intended to appropriately control the illuminance of ultraviolet rays on a substrate to be processed in an ultraviolet irradiation process so as to stably maintain processing quality and efficiency. It is a first object to provide a substrate processing apparatus having the above-mentioned configuration.

A second object of the present invention is to provide a substrate processing apparatus capable of effectively protecting a window member for irradiating ultraviolet rays from an ultraviolet ray reaction product.

[0010]

According to a first aspect of the present invention, there is provided a substrate processing apparatus for performing a predetermined process by irradiating a substrate to be processed with ultraviolet rays.
A mounting table for mounting and supporting the substrate to be processed, a lamp that emits ultraviolet light when supplied with power, and a window member that transmits ultraviolet light, and the ultraviolet light emitted from the lamp is transmitted through the window member. Ultraviolet irradiation means for irradiating the substrate to be processed on the mounting table, ultraviolet light measurement means for receiving the ultraviolet light from the ultraviolet irradiation means at a predetermined position and measuring the illuminance of the ultraviolet light, and the ultraviolet illuminance measurement means An irradiation distance adjusting means for variably adjusting the distance between the ultraviolet light irradiating means and the mounting table according to the ultraviolet irradiance measurement value obtained as described above.

In this configuration, even if the illuminance of the ultraviolet light applied to the substrate to be processed on the mounting table by the ultraviolet light irradiating means changes, the illuminance change is detected by the ultraviolet irradiance measuring means, and the illuminance change is detected by the irradiation distance adjusting means. Since the irradiation distance is variably adjusted to compensate for, the ultraviolet illuminance can be maintained constant or stable, and the quality and efficiency of the ultraviolet irradiation processing can be stably maintained.

In the substrate processing apparatus of the present invention, in order to improve the accuracy of the illuminance adjustment as described above, it is preferable that the ultraviolet illuminance measuring means includes an illuminance of the ultraviolet light applied to the substrate to be processed on the mounting table. It may be configured to include an optical sensor provided on the mounting table side at a position that does not interfere with the substrate to be processed in order to measure. In particular, when performing a scanning type ultraviolet irradiation process, it is preferable that the optical sensor is arranged at a position before the substrate to be processed in the scanning direction.

In another aspect, the irradiation distance adjusting means adjusts the distance between the ultraviolet irradiation means and the mounting table according to the thickness of the substrate to be processed mounted on the mounting table. It may be configured to include a means for variably adjusting. As described above, using the plate thickness of the substrate to be processed as a parameter for illuminance adjustment is also effective in increasing the accuracy of illuminance measurement or illuminance adjustment.

Preferably, in order to stably maintain the UV illuminance on the substrate at a desired value, the irradiation distance adjusting means preferably includes a reference illuminance setting means for setting a desired reference illuminance, and the UV illuminance measurement value. In comparison with the reference illuminance,
The apparatus may have a relative position adjusting unit that adjusts a relative position between the mounting table and the ultraviolet irradiation unit so that the comparison error approaches zero.

Preferably, in order to perform a stable and favorable ultraviolet irradiation treatment, the irradiation distance adjusting means preferably sets a maximum value for a distance between the window member and the mounting table or the substrate. And, when the interval is likely to exceed the maximum value in the variable adjustment of the interval, the interval may include a maximum interval limiting unit that limits the interval to the maximum value, and / or the window member and the mounting table described above. Or a minimum interval setting unit that sets a minimum value for the interval with the substrate, and a minimum interval limiting unit that limits the interval to the minimum value when the interval is likely to be less than the minimum value in the variable adjustment of the interval. May be provided.

According to a second aspect of the present invention, there is provided a substrate processing apparatus for performing a predetermined process by irradiating a substrate to be processed with ultraviolet rays. A mounting table for supporting, having a lamp that emits ultraviolet rays when supplied with electric power and a window member that transmits ultraviolet rays,
Ultraviolet irradiation means for irradiating the substrate to be processed on the mounting table with ultraviolet light emitted from the lamp through the window member, and a gap between the window member and the substrate to be processed on the mounting table. And a means for flowing an inert gas.

In this configuration, since the inert gas flows through the gap between the window member and the substrate to be processed on the mounting table, air, especially oxygen, can be removed from the gap by driving it out. The degree to which the ultraviolet light emitted from the window member of the means is absorbed by oxygen and attenuated before reaching the substrate to be processed is reduced. As a result, the power consumption of the lamp for obtaining the desired illuminance is reduced, and the life of the lamp is extended. In addition, since the ultraviolet reaction product is also removed from the gap by riding the flow of the inert gas, it becomes difficult to adhere to the window member.

In the substrate processing apparatus of the present invention for performing a scanning type ultraviolet irradiation treatment, the means for flowing an inert gas is preferably such that the inert gas is substantially parallel to the scanning direction from a first direction as viewed from the ultraviolet irradiation means. Inert gas injection means for feeding an inert gas into a gap between the window member and the substrate to be processed on the mounting table, and a second direction opposite to the first direction as viewed from the ultraviolet irradiation means. And inert gas suction means for sucking and discharging the inert gas passing through the gap.

[0019]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a coating and developing system as an example of a system into which the substrate processing apparatus of the present invention can be incorporated.
This coating and developing system is installed in a clean room, and performs, for example, cleaning, resist coating, pre-baking, developing and post-baking in a photolithography process in an LCD manufacturing process, for example, using an LCD substrate as a substrate to be processed. is there. The exposure processing is performed by an external exposure apparatus (not shown) installed adjacent to this system.

This coating and developing system is roughly divided into a cassette station (C / S) 10, a process station (P / S) 12, and an interface section (I / O).
/ F) 14.

A cassette station (C / S) 10 installed at one end of the system includes a cassette stage 16 on which a predetermined number of cassettes C containing a plurality of substrates G, for example, up to four, can be mounted, and a cassette stage 16 on this stage 16. And a transfer mechanism 20 for loading and unloading the substrate G with respect to the cassette C. The transfer mechanism 20 has a unit capable of holding the substrate G, for example, a transfer arm, is operable in four axes of X, Y, Z, and θ, and is a process station (P / S) described later.
The transfer of the substrate G to and from the main transfer device 38 on the 12th side can be performed.

The process station (P / S) 12
The cleaning process unit 22, the coating process unit 24, and the developing process unit 26 are sequentially changed from the cassette station (C / S) 10 side to the substrate relay unit 23, the chemical solution supply unit 25.
And are provided in a horizontal row with (and sandwiching) a space 27 therebetween.

The cleaning process unit 22 includes two scrubber cleaning units (SCRs) 28 and two upper and lower ultraviolet irradiation /
It includes a cooling unit (UV / COL) 30, a heating unit (HP) 32, and a cooling unit (COL).

The coating processing section 24 includes a resist coating unit (CT) 40 and a reduced-pressure drying unit (VD) 42
And the edge remover unit (ER) 44 and the upper and lower 2
Stage type adhesion / cooling unit (AD / COL) 4
6, upper and lower two-stage heating / cooling unit (HP / COL)
48 and a heating unit (HP) 50.

The developing process section 26 includes three developing units (DEV) 52, two upper and lower two-stage heating / cooling units (HP / COL) 55, and a heating unit (HP) 5
3 is included.

At the center of each of the process sections 22, 24 and 26, transport paths 36, 52 and 58 are provided in the longitudinal direction, and the main transport devices 38, 54 and 60 move along the respective transport paths and Each unit in the unit is accessed to carry in / out or carry in the substrate G. In this system, in each of the process units 22, 24, and 26, a spinner system unit (SCR, CT, DEV, etc.) is disposed on one side of the transport paths 36, 52, and 58, and heat treatment or heat treatment is performed on the other side. Irradiation treatment system unit (HP, CO
L, UV, etc.).

The interface unit (I / F) 14 installed at the other end of the system has an extension (substrate transfer unit) 57 on the side adjacent to the process station 12.
And a buffer stage 56, and a transport mechanism 59 on the side adjacent to the exposure apparatus.

FIG. 2 shows a processing procedure in the coating and developing system. First, the cassette station (C
/ S) 10, the transport mechanism 20 takes out one substrate G from the predetermined cassette C on the stage 16 and
It is transferred to the main transfer device 38 of the cleaning process section 22 of the process station (P / S) 12 (step S1).

In the cleaning process section 22, the substrate G
First, they are sequentially carried into an ultraviolet irradiation / cooling unit (UV / COL) 30, subjected to dry cleaning by ultraviolet irradiation in the upper ultraviolet irradiation unit (UV), and then cooled to a predetermined temperature in the lower cooling unit (COL). (Step S2). This ultraviolet irradiation cleaning removes organic substances on the substrate surface. This improves the wettability of the substrate G,
The cleaning effect in the scrubbing cleaning in the next step can be enhanced.

Next, the substrate G is placed in a scrubber cleaning unit (S
One of the CRs 28 undergoes a scrubbing cleaning process to remove particulate contamination from the substrate surface (step S3).
After the scrubbing cleaning, the substrate G is heated by a heating unit (H
(P) 32 undergoes dehydration by heating (step S)
4) Then, the substrate is cooled to a certain substrate temperature by the cooling unit (COL) 34 (step S5). Thus, the pre-processing in the cleaning process unit 22 is completed, and the substrate G is transported by the main transport unit 38 to the coating process unit 24 via the substrate transfer unit 23.

In the coating processing section 24, the substrate G
First, the adhesion / cooling unit (AD / COL) 4
6 in sequence, and the first adhesion unit (A
In D), a hydrophobizing treatment (HMDS) is performed (step S).
6) Then, the substrate is cooled to a constant substrate temperature in the next cooling unit (COL) (step S7).

Thereafter, the substrate G is coated with a resist solution in a resist coating unit (CT) 40, then subjected to a drying process under reduced pressure in a reduced-pressure drying unit (VD) 42, and then in an edge remover unit (ER) 44. Excess (unnecessary) resist on the periphery is removed (step S
8).

Next, the substrate G is supplied to the heating / cooling unit (H
P / COL) 48, and the first heating unit (HP) performs baking (pre-bake) after coating (step S9), and then cools to a constant substrate temperature by the cooling unit (COL) (step S9). Step S10). In addition,
The heating unit (HP) 50 can be used for baking after the application.

After the coating process, the substrate G is transferred to the interface (I / F) 14 by the main transfer device 54 of the coating process unit 24 and the main transfer device 60 of the development process unit 26.
To the exposure apparatus from there (step S
11). The exposure device exposes a resist on the substrate G to a predetermined circuit pattern. Then, the substrate G after the pattern exposure is transferred from the exposure apparatus to the interface unit (I / F) 14.
Is returned to. The transfer mechanism 59 of the interface unit (I / F) 14 transfers the substrate G received from the exposure apparatus via the extension 57 to the process station (P / S) 1.
(Step S11).

In the developing process section 26, the substrate G
One of the developing units (DEV) 52 undergoes a developing process (step S12), and then is sequentially loaded into one of the heating / cooling units (HP / COL) 55, and is post-baked in the first heating unit (HP). Is performed (step S13), and then cooled to a certain substrate temperature by the cooling unit (COL) (step S14). A heating unit (HP) 53 can be used for this post-baking.

The substrate G that has been subjected to a series of processes in the developing process section 26 is returned to the cassette station (C / S) 10 by the transfer devices 60, 54, and 38 in the process station (P / S) 24. Stored in one of the cassettes C by the transport mechanism 20 (step S
1).

In this coating and developing system, the present invention can be applied to the ultraviolet irradiation unit (UV) of the cleaning process section 22. Hereinafter, an embodiment in which the present invention is applied to an ultraviolet irradiation unit (UV) will be described with reference to FIGS.

As shown in FIG. 3, an ultraviolet irradiation unit (UV) according to one embodiment of the present invention has an ultraviolet irradiation window 62 made of synthetic quartz glass attached to the lower surface, and a plurality of windows (in the illustrated example, 3). Book) cylindrical ultraviolet lamp 64 (1), 6
4 (2) ‥‥, 64 (n) are housed side by side in a horizontal direction orthogonal to the longitudinal direction of the lamp, and a cleaning chamber 68 provided adjacent to and below the lamp chamber 66. Having.

In the lamp chamber 66, each of the ultraviolet lamps 64 (1) to 64 (n) may be, for example, a dielectric barrier discharge lamp, and emits light when supplied with commercial AC power from a lamp power supply (120) described later. It emits ultraviolet light (ultraviolet excimer light) having a wavelength of 172 nm, which is suitable for cleaning organic contaminants. A concave reflecting mirror 70 having an arc-shaped cross section is disposed behind, that is, above, each of the ultraviolet lamps 64 (1) to 64 (n), and above or to the side of each of the lamps 64 (1) to 64 (n). The emitted ultraviolet light is reflected by the concave surface of the reflector just above and directed to the ultraviolet irradiation window 62 side.

An ultraviolet lamp 64 is provided in the lamp chamber 66.
A cooling jacket (not shown) for cooling (1) to 64 (n) by, for example, a water-cooling method, or an inert gas for preventing ultraviolet light absorbing (deteriorating lamp luminous efficiency) oxygen from entering the room. For example, a gas distribution mechanism (not shown) for introducing and filling N2 gas may be provided.

On both sides of the lamp chamber 66, an inert gas injection section 72 for flowing an inert gas for removing oxygen or air, such as N 2 gas, along the lower surface of the ultraviolet irradiation window 62 during the ultraviolet cleaning process, and an inert gas injection section 72 A gas suction section 74 is provided.

The inert gas injection section 72 is disposed on the right side of the lamp chamber 66 in FIG. 3, that is, on the front side in the table moving direction (Y direction) during scanning, which will be described later, and has ultraviolet lamps 64 (1) to 64. Gas pipe 7 extending parallel to (n)
6, a large number of inert gas injection ports 78 provided in a line at regular intervals in the gas pipe 76,
An inert gas supply unit 80 for supplying an inert gas at a predetermined flow rate and a predetermined pressure, and a gas guide member 82 for guiding the inert gas injected from each inert gas injection port 78 below the ultraviolet irradiation window 62. have.

The inert gas suction section 74 is disposed on the left side of the lamp chamber 66 in FIG. 3, that is, on the rear side in the table moving direction (Y direction) during scanning, and has the ultraviolet lamps 64 (1) to 64 (n). Gas pipe 84 extending parallel to
A large number of gas inlets 86 provided in a line at regular intervals in the gas pipe 84, and a gas exhaust unit 8 for applying a negative pressure to the gas pipe 84 and exhausting the gas that has flowed in.
8, and a gas guide member 90 for guiding the inert gas flowing below the ultraviolet irradiation window 62 from the inert gas injection unit 72 toward the gas inlet 86. The positions of the inert gas injection unit 72 and the inert gas suction unit 74 may be reversed with respect to the lamp chamber 66.

A utility supply unit and a control unit for supplying a required utility or control signal to each unit in the ultraviolet irradiation unit (UV) adjacent to the outside of the inert gas injection unit 72 and the inert gas suction unit 74. A utility unit 92 for housing the unit is provided.

A horizontally movable and vertically movable stage 94 for placing and supporting the substrate G is provided in the cleaning processing chamber 68.
Is provided. In this embodiment, the ball screw 96
Stage 9 on a self-propelled stage drive 98 using
4 is mounted so as to be able to move up and down in the vertical direction (Z direction in the figure). It is configured to be able to reciprocate at a variable controllable speed so as to cross in parallel with the lamp arrangement direction.

A plurality of (for example, six) lift pins 102 for supporting the substrate G in a horizontal posture when loading / unloading the substrate G are vertically penetrated through the stage 94. In this embodiment, each lift pin 102 is fixed at a predetermined height position for substrate transfer, and when loading / unloading the substrate G,
With respect to these fixed lift pins 102, the lower limit height position Hb for retracting the stage 94 so as not to hinder the loading / unloading of the substrate G, and the upper limit height position indicated by a dashed line for placing and supporting the substrate G by itself. It is possible to move up and down with Ha by an elevating mechanism (not shown).

The stage 94 is formed to have a size slightly larger than the substrate G, and a predetermined area (substrate mounting area) 94a near the center where the substrate G is mounted has a large number of supports for supporting the substrate G. A pin (not shown) and a vacuum chuck suction port (not shown) for sucking and holding the substrate G are provided. In FIG. 3, a lamp chamber 66 is provided on the right side end 94b of the stage, which is located on the right side of the substrate mounting area 94a, more specifically, on the front side in the stage forward direction (Y direction) as shown in FIG. There is provided an optical sensor 104 for measuring the illuminance of the ultraviolet light applied to the substrate G on the stage 94 from above.

In FIG. 3, the substrate G is loaded / unloaded into the side wall of the cleaning chamber 68 adjacent to the origin position of the stage 94 in the Y direction at a height near the upper end of the fixed lift pins 102.
An openable and closable shutter (door) 106 for carrying out is mounted. The shutter 106 faces the transport path 36 (FIG. 1) of the cleaning process unit 22, and the substrate G is transferred from the transport path 36 into the cleaning processing chamber 68 through the shutter 104 in which the main transport device 38 is open. Loading and unloading can be performed.

One or more exhaust ports 108 are provided on the side wall or bottom surface of the cleaning processing chamber 68, and each exhaust port 108 is connected to an exhaust system such as an exhaust duct (not shown) via an exhaust pipe 110. It is connected to the. Further, the cleaning processing chamber 68
An outside air suction port (not shown) may be provided at an appropriate place in the apparatus.

FIG. 5 shows the ultraviolet irradiation unit (UV)
3 shows the configuration of the control system. The control unit 112 may be composed of a microcomputer and necessary peripheral circuits, and a built-in memory stores necessary programs for controlling each unit in the unit and the whole, and via an appropriate interface It is connected to a main controller (not shown) that controls the overall processing procedure of the present coating and developing processing system and to various parts of a control system in the present ultraviolet irradiation unit (UV).

In this embodiment, a main part in the ultraviolet irradiation unit (UV) related to the control unit 112 drives a shutter drive unit 114 for opening and closing the shutter 106 and a stage 94 in the Z direction. Raising and lowering drive unit 116 for scanning, driving unit 118 for horizontally or scanningly driving stage 94 in the Y direction, and lamp for lighting and driving ultraviolet lamps 64 (1) to 64 (n) in lamp chamber 66. A power supply section 120, an inert gas flow driving section 122 for creating an inert gas flow below the ultraviolet irradiation window 62 of the lamp chamber 66, sensors 124 for detecting the state or state quantity of each section in the apparatus, and the like. It is.

The stage elevating drive unit 116 and the scanning drive unit 118 have, for example, servo motors as respective drive sources, and are provided in the stage drive unit 98. The inert gas flow drive unit 122 opens and closes the on-off valves provided in the inert gas supply unit 80 of the inert gas injection unit 72 and the gas exhaust unit 88 of the inert gas suction unit 74, respectively. The sensors 112 include a right end 94 of the stage 94.
b includes the above-mentioned optical sensor 104.

FIG. 6 shows the ultraviolet irradiation unit (UV)
3 shows the configuration of an illuminance adjustment unit for adjusting the illuminance of ultraviolet light emitted from the lamp chamber 66 to the substrate G on the stage 94 to a predetermined value. In this illuminance adjustment unit, a part 12 excluding the optical sensor 104 and the stage elevation drive unit 116
8 to 138 are included in the control unit 112.

An output signal (for example, a photocurrent) of the optical sensor 104 is input to the illuminance measuring circuit 128. The illuminance measurement circuit 128 determines the value of the output signal of the optical sensor 104 and the value of the optical sensor 1.
The measured value (or may be an estimated value) of the ultraviolet illuminance E on the surface of the substrate G on the stage 94 using the offset d of the height position between the light receiving surface of the substrate G and the surface of the substrate G as a variable.
Is obtained by required signal processing or arithmetic processing. Here, the height position Sh of the light receiving surface of the optical sensor 104 is constant with the substrate mounting surface 94a of the stage 94 as a reference surface.
Is set in the thickness setting section 130 as one of condition data or attribute data relating to the substrate to be processed which is currently flowing (being processed) in the coating and developing system. Therefore, the height position offset d is given by d = Gt-Sh.

The ultraviolet illuminance measured value E obtained from the illuminance measuring circuit 128 is given to the illuminance comparing section 132. The illuminance comparison unit 132 compares the ultraviolet illuminance measurement value E with the reference illuminance setting unit 1.
Then, the difference between the two is compared with the reference illuminance Es from E.34, that is, the error δE is obtained. Here, the reference illuminance Es may be set to an appropriate illuminance that can guarantee a desired ultraviolet light cleaning effect at a predetermined scanning speed.

The stage elevation control unit 136 drives and controls the stage elevation drive unit 116 in accordance with the illuminance error δE from the illuminance comparison unit 132 so that the error δE approaches zero, and controls the height of the stage 94 for mounting the substrate. Change the position Ha.
Thus, when the measured ultraviolet illuminance E obtained from the illuminance measurement circuit 128 matches the reference illuminance Es, the variable adjustment of the stage height position is stopped.

However, the stage elevating control unit 136 obtains the position information indicating the stage height position from a predetermined position sensor (not shown) or the like and the substrate thickness (Gt) data from the thickness setting unit 130. The distance D between the substrate G on the stage 94 and the ultraviolet irradiation window 62 of the lamp chamber 66 is monitored.
38, the data of the maximum value Dmax and the minimum value Dmin is received. Then, in the process of changing the height position of the stage 94 according to the illuminance error δE from the illuminance comparison unit 132, the interval D becomes the maximum value Dmax (for example, 7 mm) or the minimum value Dmin.
(For example, 3 mm), the height adjustment of the stage 94 is forcibly stopped there, and the interval D is set to the maximum value Dma.
x or the minimum value Dmin is limited or fixedly held.

FIG. 7 shows the ultraviolet irradiation unit (UV)
The main operation procedure in is shown. First, upon receiving an instruction from the main controller, each unit in the unit including the control unit 112 is initialized (step A1). During this initialization, the stage 94 moves the shutter 106 in the Y direction.
Is located at a predetermined origin position close to, and is lowered to a retreat height position (Hb) in the Z direction.

When the main transfer device 38 (FIG. 1) transfers the unprocessed substrate G from the cassette station (C / S) 10 to a position before the main ultraviolet irradiation unit (UV), the controller 1
Numeral 12 controls the respective units so as to transfer the substrate G to and from the main transfer device 38 (step A2).

More specifically, first, the shutter driving unit 114
To open the shutter 106. Main transfer device 3
Numeral 8 has a pair of transfer arms. The substrate G before cleaning is placed on one of the transfer arms, and the other transfer arm is made empty (no substrate). This ultraviolet irradiation unit (U
When there is no cleaned substrate G in V), the transfer arm supporting the substrate G before cleaning is directly extended into the cleaning processing chamber 68 through the shutter 106 in the open state, and the uncleaned substrate G is removed. It is mounted on the fixed lift pins 102. If there is a cleaned substrate G in the ultraviolet irradiation unit (UV), first, the cleaned substrate G is emptied by an empty transfer arm.
Is carried out, and the uncleaned substrate G is carried in in the same manner as described above. As described above, the ultraviolet irradiation unit (U
In step V), when the substrate G to be subjected to the ultraviolet cleaning process is loaded and mounted on the fixed lift pins 102 by the main transfer device 38, the shutter 106 is closed.

Next, the control section 112 controls the stage up / down drive section 116 to raise the stage 94 to the reference height position Ha0 for mounting the substrate (step A3). At this time, the suction of the vacuum chuck portion may be started while the stage 94 moves up, so that the substrate G can be sucked and held at the same time when the stage 94 reaches the reference height position Ha0 for mounting the substrate. Note that an appropriate margin may be set between the reference height position Ha0 for mounting the substrate and the height position of the tip of the fixed lift pin 102.

Next, the controller 112 controls the lamp power supply 12
0 to control the ultraviolet lamps 64 (1) to 64 (n) (step A4).
2 to control the inert gas injection unit 72 and the inert gas suction unit 74 (step A5). As a result, the inert gas injection section 72 on the right side of the lamp chamber 66 feeds the inert gas (N2 gas) below the ultraviolet irradiation window 62, and the inert gas suction section 74 on the left side or downstream side of the lamp chamber 66. Sucks the inert gas, whereby an inert gas flow is formed along the lower surface of the ultraviolet irradiation window 62 in parallel with the stage moving direction (Y direction).

Next, the control unit 112 performs illuminance adjustment (step A6) before starting the ultraviolet cleaning process (step A7).

FIG. 8 shows a procedure for adjusting the illuminance according to one embodiment. First, if it is necessary to position the illuminance measuring optical sensor 104 with respect to the lamp chamber 66, this is performed (step B1). For example, at the origin position in the Y direction in FIG.
If it is deviated from the ultraviolet irradiation area immediately below the position 2, the stage 94 may be moved somewhat in the Y direction so that the optical sensor 104 is inserted into the ultraviolet irradiation area. Also,
In the Z direction, the reference height position Ha0 for mounting the substrate
It is also possible to set a reference position Ha1 for illuminance adjustment different from that described above, and adjust the stage 94 to the height position Ha1.

After setting the optical sensor 104 at a predetermined position with respect to the lamp chamber 66 as described above, the illuminance measuring circuit 128 and the thickness setting unit 130 in the illuminance control unit (FIG. 6) set the substrate on the stage 94. The illuminance of the ultraviolet rays with respect to G is measured (step B2). Next, the reference illuminance E is set by the illuminance comparison unit 132 and the reference illuminance setting unit 134.
An error δE (δE = Es−E) of the illuminance measurement value E with respect to s is obtained (step B3).

Then, the stage elevation control unit 136 determines the polarity and absolute value of the error δE (step B).
4) The stage 9 is controlled by controlling the
4 is selectively variably adjusted (steps B5 to B5).
B11).

In this embodiment, when δE <0, that is, when the illuminance measurement value E is larger than the reference illuminance Es, the stage height position Ha is basically lowered by a predetermined pitch (for example, 0.1 mm). UV irradiation window 62 and stage 9
The distance D from the substrate G on the substrate 4 is widened by the pitch (step B6), and the process returns to the illuminance measurement (steps B12 and B
2). However, when the interval D has reached or exceeds the maximum value Dmax provided by the maximum / minimum interval setting unit 138, the stage 94 is fixed at a height position where the interval D stops at the maximum value Dmax ( Step B8). Usually, the interval D is adjusted to the vicinity of the maximum value Dmax when the lamp brightness on the lamp chamber 66 side is the maximum, that is, immediately after the use of the ultraviolet lamps 62 (1) to 62 (n) is started or immediately after replacement.

When δE> 0, that is, when the measured illuminance value E is smaller than the reference illuminance Es, the stage height position Ha is raised by a predetermined pitch (for example, 0.1 mm) in principle and the ultraviolet irradiation window 62 is increased. The distance D between the target and the substrate G on the stage 94 is narrowed by the pitch (step B10), and then the process returns to the illuminance measurement (steps B12 and B2). But,
If the interval D has reached the minimum value Dmin provided by the maximum / minimum interval setting section 138 or is likely to divide it, the stage 94 is fixed at a height position where the interval D stops at the minimum value Dmin (step B11). ). Further, the interval D is adjusted to the minimum value Dmin in this manner because the lamp chamber 66
Since the brightness of the ultraviolet lamps 62 (1) to 62 (n) in FIG. 6 is considerably reduced due to deterioration over time or the like, an alarm may be issued to prompt maintenance such as lamp replacement (step B11). When such an alarm is issued, the ultraviolet cleaning process may be stopped.

When the measured illuminance value E matches the reference illuminance Es (δE = 0), the process returns to the illuminance measurement without changing the height position Ha of the stage 94 (steps B5 and B2). The value of the reference illuminance Es is given an appropriate width or range, and when the illuminance measurement value E falls within the range, the two coincide (δE = 0).
It is also possible to regard as.

In this embodiment, feedback is applied until the measured illuminance value E matches the reference illuminance Es, so that highly accurate illuminance adjustment can be performed. However, an adjustment target value of the interval or the stage height position according to the comparison error δE from the illuminance comparison unit 132 is calculated, and the height position of the stage 94 is adjusted by open loop control so as to reach the adjustment target value. It is also possible.

During the above-described illuminance adjustment (step A6), the gap P between the ultraviolet irradiation window 62 and the right end 94b of the stage is not subjected to the same conditions as in the ultraviolet irradiation cleaning process described later. An inert gas (N2 gas) flows from the active gas injection unit 72 to the inert gas suction unit 74. The flow F of the inert gas (FIG. 3) has a function of effectively removing air, particularly oxygen, from the gap P. Thereby, the degree of absorption of ultraviolet rays (ultraviolet excimer light) emitted vertically downward from the ultraviolet irradiation window 62 of the lamp chamber 66 by the oxygen before reaching the light receiving surface of the optical sensor 104 is greatly reduced, and The illuminance on the stage at the same interval D is greatly improved as compared with the case where there is no flow of the inert gas. The flow F of the inert gas preferably flows closer to the ultraviolet irradiation window 62 than to the stage.

After the illuminance adjustment (Step A6) as described above, an ultraviolet cleaning process is performed on the substrate G on the stage 96 (Step A7). To perform this ultraviolet irradiation cleaning process, the control unit 112 causes the scanning drive unit 118 in the stage drive unit 98 to move the stage 94 one-way or reciprocate in the Y direction between the origin position and the forward movement position indicated by the dotted line 94 ′. Let it. In this stage movement, the stage 94
Adjusts the illuminance immediately below the lamp chamber 66 (step A6)
Traverses in the Y direction at the height position determined by the above, the ultraviolet rays having a wavelength of 172 nm emitted from the ultraviolet irradiation window 62 of the lamp chamber 66 substantially vertically downward irradiate the substrate G with illuminance substantially equal to the reference illuminance. While scanning from one end to the other end of the substrate in the direction opposite to the stage movement direction (Y direction).

As described above, the wavelength of the substrate G is 172 nm.
Is irradiated, the oxygen existing near the substrate surface is changed into ozone O3 by the ultraviolet light, and the ozone O3 is excited by the ultraviolet light to generate oxygen atom radicals O *. Due to the oxygen atom radicals, organic substances attached to the surface of the substrate G are decomposed into carbon dioxide and water and removed from the substrate surface. The decomposed and vaporized organic matter is exhausted from the exhaust port 108.

In such a scanning type ultraviolet cleaning process, the irradiation amount or the integrated light amount of the ultraviolet ray to the substrate G is inversely proportional to the moving speed (scanning speed) of the stage 94. That is, as the scanning speed F increases, the ultraviolet irradiation time on the substrate G decreases and the amount of ultraviolet irradiation decreases. On the contrary, as the scanning speed decreases, the ultraviolet irradiation time on the substrate G increases and the amount of ultraviolet irradiation increases. . Within a certain limit, the larger the amount of ultraviolet irradiation, the more organic substances are removed from the surface of the substrate G.

In this embodiment, the illuminance of the ultraviolet light applied to the substrate G on the stage 94 from the lamp chamber 66 is adjusted to a value near the reference illuminance in the illuminance adjustment (step A6) as described above. Since the scanning-type ultraviolet cleaning process (Step A7) is performed, even if the luminance of the ultraviolet lamps 64 (1) to 64 (n) in the lamp chamber 66 is reduced due to aging, the ultraviolet irradiation time and the scanning speed are set to the set values. , And good cleaning process quality can be maintained.

During the ultraviolet cleaning process, as shown in FIG. 9, the inert gas injection unit 72 and the inert gas suction unit 74 connect the ultraviolet irradiation window 62 of the lamp chamber 66 to the substrate G on the stage 94. Inert gas (N2
A flow F of gas) is formed. As in the case of the illuminance adjustment (step A6), the flow F of the inert gas has a function of effectively removing air, particularly oxygen, from the gap P.
Note that oxygen adhering or floating near the surface of the substrate G is not so much eliminated, and oxygen necessary for generation of ozone for ultraviolet cleaning processing is sufficiently secured.

As described above, the oxygen in the air is removed from the gap P by the flow F of the inert gas.
Ultraviolet rays (ultraviolet excimer light) emitted vertically downward from the ultraviolet irradiation window 62 can reach each part of the substrate surface without being attenuated so much. For this reason, in the lamp chamber 66, the lamp input power can be reduced by that much, and the life of the lamp 64 can be extended. Further, the ultraviolet ray reaction product generated in association with the ultraviolet ray cleaning process is drawn into the inert gas suction section 74 so as to be drawn into the inert gas flow F and discharged to the outside. Also has the advantage that it is difficult to adhere.

When the scanning type ultraviolet cleaning process for the substrate G on the stage 94 as described above is completed, the control unit 1
12 controls the lamp power supply unit 120 to control the ultraviolet lamp 64
(1) to 64 (n) are turned off (step A8). And
Immediately thereafter, the inert gas flow driving unit 122 is controlled to stop the flow F of the inert gas immediately below the ultraviolet irradiation window 62 (step A9).

Next, the control section 112 returns the stage 94 to the start position (step A10). In this embodiment, first, the stage 94 is moved backward by the scanning drive unit 118, then the vacuum chuck is turned off at the origin position in the Y direction, and then the stage 94 is moved by the stage elevation drive unit 116 to the retreat height position (Hb). ), And the substrate G is supported by the fixed lift pins 102. In this way, all the steps in the main ultraviolet ray cleaning unit (UV) for one substrate G are completed, and the process waits for the arrival of the main transfer device 38 (FIG. 1).

In the case where the ultraviolet cleaning process is performed in a scanning manner as in the above-described embodiment, the illuminance adjusting unit is used when the illuminance measuring optical sensor 104 on the stage 94 passes through the ultraviolet irradiation window 62 of the lamp chamber 66. It is also possible to measure or monitor the UV illuminance (distribution) immediately below the UV irradiation window 62 by operating the illuminance monitor function (FIG. 6). By this illuminance monitor function, each ultraviolet lamp 64 (1) in the lamp chamber 66 is
The luminance of ~ 64 (n) is monitored from the stage 94 side, and a lamp having an abnormally low luminance or a lamp which cannot be turned on can be detected.

In the above-described embodiment, the scanning method is such that the lamp chamber 66 is fixed and the stage 94 is moved in parallel with the surface of the substrate G. However, a scanning method in which the stage 94 is fixed at a predetermined position and the lamp chamber 66 is moved in parallel with the surface of the substrate G is also possible.

Further, the relative movement between the lamp chamber 66 and the stage 94 for ultraviolet ray scanning can be realized by a rotational movement. 10 and 11 show examples of the configuration of a rotary scanning apparatus. In the figure, parts having the same configuration or function as those of the above-described embodiment are denoted by the same reference numerals. In this configuration example, the stage driving unit 140 is provided with a stage elevating mechanism and a rotating mechanism (not shown). When performing the ultraviolet irradiation process, the rotating mechanism operates to move the stage 94 and the substrate G to the stage center vertical axis O. It rotates around at a predetermined speed. A configuration in which the stage 94 side is fixed and the lamp chamber 66 side is rotationally moved is also possible.

According to such a rotary scanning method, the planar space of the stage 94 or the lamp chamber 66 can be kept to a minimum, so that the apparatus space can be reduced in size. Further, as shown in FIG. 11, the required length of the ultraviolet lamps 64 (1) to 64 (n) in the lamp chamber 66 can be reduced.

The structure in the lamp chamber 66 and the cleaning processing chamber 68 in the above-described embodiment, particularly, the ultraviolet irradiation window 62, the ultraviolet lamps 64 (1) to 64 (n), the stage 94, the stage driving sections 98 and 140, the illuminance The configuration of the adjustment unit (FIG. 6) and the like is also an example, and various modifications can be made to each unit.

In the above-described embodiment, the illuminance measuring optical sensor 104 is arranged at the position closest to the substrate G on the stage 94, and the ultraviolet illuminance on the substrate G is measured based on the output signal of the optical sensor 104. Highly accurate illuminance measurement can be performed. However, although the accuracy is reduced, it is also possible to dispose such an optical sensor 104 for measuring the illuminance in another place, for example, outside the stage 94, or to arrange the light receiving surface in the substrate mounting area 94a on the stage 94. May be exposed and buried.

In the above embodiment, in order to variably adjust the distance (illumination distance) between the lamp chamber 66 and the stage 94, the lamp chamber 66 is fixedly arranged, and the height position of the stage 94 is variably adjusted. However, conversely, a configuration in which the height position of the stage 94 is fixed and the height position of the lamp chamber 66 is variably adjusted is possible, or a configuration in which both positions are variably adjusted is also possible.

In the above embodiment, the illuminance is measured or the stage height is adjusted in accordance with the thickness Gt of the substrate G placed on the stage 94, so that the illuminance can be adjusted with higher accuracy. However, although the accuracy is low, even if the distance (illumination distance) between the lamp chamber 66 and the stage 94 is variably adjusted ignoring the plate thickness Gt of the substrate G, practically sufficient illuminance adjustment is possible.

In the above embodiment, the ultraviolet irradiation cleaning device (U
V). However, the substrate processing apparatus of the present invention is also applicable to a process of irradiating a substrate to be processed with ultraviolet rays for a purpose other than the removal of organic contamination. For example, in the coating and developing system as described above, the same ultraviolet irradiating apparatus as in the above embodiment can be used in the step of irradiating the substrate G with ultraviolet rays for the purpose of curing the resist after the post-baking (step S13). The substrate to be processed in the present invention is not limited to the LCD substrate, but may be a semiconductor wafer, a CD substrate, a glass substrate, a photomask, a printed substrate, or the like.

[0090]

As described above, according to the substrate processing apparatus of the present invention, the irradiance of the ultraviolet light to the substrate to be processed in the ultraviolet irradiation processing is properly controlled, and the processing quality and efficiency are stably maintained. Can be. In addition, the window member for ultraviolet irradiation can be effectively protected from ultraviolet reaction products.

[Brief description of the drawings]

FIG. 1 is a plan view showing a configuration of a coating and developing processing system to which a substrate processing apparatus of the present invention can be applied.

FIG. 2 is a flowchart illustrating a processing procedure in the coating and developing processing system according to the embodiment.

FIG. 3 is a perspective view illustrating a configuration of an ultraviolet irradiation unit according to the embodiment.

FIG. 4 is a perspective view showing an attachment structure of an illuminance measurement optical sensor in the ultraviolet irradiation unit of the embodiment.

FIG. 5 is a block diagram illustrating a configuration of a control system of the ultraviolet irradiation unit according to the embodiment.

FIG. 6 is a block diagram illustrating a configuration example of an illuminance adjustment unit in the ultraviolet irradiation unit according to the embodiment.

FIG. 7 is a flowchart showing a main operation procedure in the ultraviolet irradiation unit of the embodiment.

FIG. 8 is a flowchart illustrating a procedure of illuminance adjustment in the ultraviolet irradiation unit of the embodiment.

FIG. 9 is a partial side view showing an operation of a method of flowing an inert gas into a gap between an ultraviolet irradiation window and a substrate in the ultraviolet irradiation unit of the embodiment.

FIG. 10 is a perspective view illustrating a configuration of an ultraviolet irradiation unit according to another embodiment.

FIG. 11 is a plan view illustrating a main part of an ultraviolet irradiation unit according to another embodiment.

[Explanation of symbols]

 38 Main carrier unit UV UV irradiation unit 62 UV irradiation window (quartz glass window) 64 (1), 64 (2), ‥‥, 64 (n) UV lamp 66 Lamp room 68 Cleaning treatment room 72 Inert gas injection unit 74 Inert gas suction unit 94 Stage 94a Substrate mounting area 94b Right end of stage 98 Stage drive unit 104 Optical sensor 112 Control unit 116 Stage up / down drive unit 118 Scan drive unit 122 Inert gas flow drive unit 128 Illuminance measurement circuit 130 Plate thickness Setting unit 132 illuminance comparison unit 134 reference illuminance setting unit 136 stage elevation control unit 138 maximum / minimum interval setting unit 140 stage drive unit

Continued on the front page F term (reference) 5F031 CA02 CA05 FA01 FA07 FA12 GA47 GA48 GA50 HA13 HA33 HA57 HA58 HA59 JA02 JA05 JA13 JA32 JA45 LA12 MA02 MA03 MA23 NA04 NA16 5F046 HA03 MA13

Claims (11)

[Claims] 1. A substrate processing apparatus for performing predetermined processing by irradiating a substrate to be processed with ultraviolet light, comprising: a mounting table for mounting and supporting the substrate to be processed; and a lamp for receiving the supply of electric power and emitting ultraviolet light. A window member that transmits ultraviolet light, an ultraviolet irradiation unit that irradiates the substrate to be processed on the mounting table with ultraviolet light emitted from the lamp through the window member, and an ultraviolet light from the ultraviolet irradiation unit. An ultraviolet illuminance measuring unit that receives light at a predetermined position and measures the illuminance of the ultraviolet light, and variably adjusts a distance between the ultraviolet irradiating unit and the mounting table according to an ultraviolet illuminance measurement value obtained from the ultraviolet illuminance measuring unit. A substrate processing apparatus comprising: 2. An irradiation distance adjusting means for variably adjusting a distance between the ultraviolet irradiation means and the mounting table according to a thickness of the substrate to be processed mounted on the mounting table. The substrate processing apparatus according to claim 1, further comprising: 3. An irradiation distance adjusting means, comprising: a reference illuminance setting means for setting a desired reference illuminance; and comparing the ultraviolet illuminance measurement value with the reference illuminance so as to make a comparison error close to zero. 3. The substrate processing apparatus according to claim 1, further comprising a relative position adjusting unit that adjusts a relative position between the mounting table and the ultraviolet irradiation unit. 4. An irradiation distance adjusting means, a maximum interval setting means for setting a maximum value of an interval between the window member and the mounting table or the substrate, and the variable value adjustment of the interval, the interval is the maximum value. The substrate processing apparatus according to any one of claims 1 to 3, further comprising a maximum interval limiting means for limiting the interval to the maximum value when the interval is likely to exceed. 5. An irradiation distance adjusting means, a minimum interval setting means for setting a minimum value for an interval between the window member and the mounting table or the substrate, and the variable interval adjusting means sets the interval to the minimum value. A minimum interval limiting means for limiting the interval to the minimum value when the interval is likely to be divided, and an alarm means for generating an alarm when the interval is likely to be less than the minimum value.
5. The substrate processing apparatus according to any one of 4. 6. The ultraviolet irradiance measuring means is provided on the mounting table side at a position not interfering with the substrate to measure the illuminance of ultraviolet light applied to the substrate on the mounting table. The substrate processing apparatus according to claim 1, further comprising an optical sensor. 7. One or both of the mounting table and the ultraviolet irradiation means in a predetermined direction so that the ultraviolet light from the ultraviolet irradiation means scans the processing surface of the substrate to be processed on the mounting table. The substrate processing apparatus according to any one of claims 1 to 6, further comprising a driving unit for moving the substrate. 8. The substrate processing apparatus according to claim 7, wherein the optical sensor is arranged at a position before the substrate to be processed in the scanning direction. 9. A substrate processing apparatus for performing predetermined processing by irradiating a substrate to be processed with ultraviolet light, comprising: a mounting table for mounting and supporting the substrate to be processed; and a lamp for receiving the supply of power and emitting ultraviolet light. A window member that transmits ultraviolet light, and an ultraviolet irradiation unit that irradiates the substrate to be processed on the mounting table through the window member with ultraviolet light emitted from the lamp; and on the mounting table and the window member. Means for flowing an inert gas into a gap between the substrate and the substrate to be processed. 10. A substrate processing apparatus for performing predetermined processing by irradiating a substrate to be processed with ultraviolet light, comprising: a mounting table for mounting and supporting the substrate to be processed; and a lamp for receiving the supply of electric power and emitting ultraviolet light. A window member that transmits ultraviolet light, an ultraviolet irradiation unit that irradiates the substrate to be processed with ultraviolet light emitted from the lamp through the window member, and the ultraviolet light from the ultraviolet irradiation unit is on the mounting table. Driving means for moving one or both of the mounting table and the ultraviolet irradiation means in a predetermined direction so as to scan the processing surface of the processing substrate, and from a first direction viewed from the ultraviolet irradiation means An inert gas injection unit that feeds an inert gas into a gap between the window member and the substrate to be processed on the mounting table substantially in parallel with the scanning direction; 1 of a substrate processing apparatus including the inert gas suction means for discharging inhale the inert gas which has passed through the gap in the second direction opposite to the direction. 11. The apparatus according to claim 1, wherein the driving unit has a rotation driving unit that rotates one of the mounting table and the ultraviolet irradiation unit while rotating the other at a second position while fixing the other at a first position. The substrate processing apparatus according to claim 7, wherein: