JP2011054608A - Proximity scan aligner and method of controlling the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a proximity scan aligner capable of precisely performing exposure without any irregularities in the exposure by fixing illuminance between respective light sources by restraining variations in an illuminometer, and to provide a method of controlling the proximity scan aligner. <P>SOLUTION: A light source control section 15a of the proximity scan aligner 1 includes a correction function 15b for correcting illuminance signals from each illuminometer 50 according to reference illuminance detected by a reference illuminometer 60. By restraining variations in each illuminometer 50 by the reference illuminometer 60, illuminance between respective irradiation sections 14 is fixed, thus eliminating irregularities in exposure and performing exposure precisely. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a proximity scan exposure apparatus and a control method thereof, and more particularly to a proximity scan exposure apparatus that prevents uneven exposure by exposing with a precise illuminance when a substrate is exposed, and a control method thereof.

  In proximity exposure, a translucent substrate (material to be exposed) coated with a photosensitive agent on the surface is held on a substrate stage, and the substrate is brought close to a mask held on a mask holding frame of the mask stage (for example, several 10 μm to several hundreds of μm), and then the exposure optical pattern is irradiated onto the mask by irradiating light for exposure toward the mask by the illumination optical system from the side away from the substrate of the mask so that the exposure pattern drawn on the mask is transferred onto the substrate. Yes.

  The high-pressure mercury lamp, which is generally used as a light source in the illumination optical system used in such an exposure apparatus, is used in continuous lighting to stabilize the performance. When exposing a substrate, the high-pressure mercury lamp is used. The exposure amount for pattern exposure applied to the substrate is controlled by opening and closing a shutter disposed in front of the lamp. In order to transfer the exposure pattern with high accuracy, the integrated exposure amount (product of the illuminance of light and the irradiation time) irradiated to the substrate is an important factor, and the illuminance of the light irradiated by the illuminance sensor is detected, The integrated exposure amount is controlled to be constant by changing the irradiation time based on the illuminance of the detected light.

  Here, since the illuminance of the high-pressure mercury lamp has a characteristic that it gradually decreases in proportion to the lighting time, in order to keep the integrated exposure amount constant, the exposure time is set along with the lighting time of the high-pressure mercury lamp. It needs to be long.

  For example, in the exposure apparatus described in Patent Document 1, the illuminance of light emitted from a high-pressure mercury lamp is measured by an illuminance sensor, and the supply voltage is adjusted with respect to the decrease in illuminance, so that the illuminance on the mask is always set to a predetermined value. keeping.

Further, in the exposure apparatus described in Patent Document 2, a proximity scan exposure apparatus that performs exposure using a plurality of exposure light beams arranged close to each other along a direction intersecting the transport direction with respect to a substrate transported at a constant speed. It has been known.
JP-A-8-8154 JP 2006-292955 A

By the way, in the proximity scan exposure apparatus described in Patent Document 2, exposure is performed using a plurality of exposure lights arranged close to each other along a direction intersecting the transport direction with respect to a substrate transported at a constant speed. Therefore, it is necessary to control the illuminance between the exposure light beams to be constant. This is because if the illuminance between the exposure lights is not constant, unevenness is caused. For this reason, it is also conceivable to control the supply voltage of the high-pressure mercury lamp based on the illuminance measured by the illuminance sensor as in the exposure apparatus described in Patent Document 1 for each exposure light source. In addition, variations in illuminance between light sources are alleviated.
However, the illuminometer generally used in the exposure apparatus has a solid difference in its output level and change with time. For this reason, when a plurality of illuminance meters are used side by side, the variation in the illuminance meter itself is a major factor in the variation in illuminance.

  The present invention has been made in view of the above circumstances, and its purpose is to eliminate uneven exposure and to perform exposure with high accuracy by making the illuminance between each light source constant by suppressing variations in the illuminance meter. An object of the present invention is to provide a proximity scanning exposure apparatus and a control method thereof that can be performed.

The above object of the present invention can be achieved by the following constitution.
(1) Irradiating exposure light to a substrate conveyed in a predetermined direction through a plurality of masks arranged close to each other along a direction intersecting the predetermined direction, and patterning the plurality of masks on the substrate A proximity scanning exposure apparatus for exposing,
A plurality of irradiation units respectively disposed on top of the plurality of masks and irradiating the exposure light;
An illuminometer provided in the irradiating unit for detecting the illuminance of the light;
A light source control unit for controlling the power of the irradiation unit according to an illuminance signal from the illuminometer;
A reference illuminometer that detects a reference illuminance of each irradiation unit by moving between the irradiation units, and
The proximity scanning exposure apparatus, wherein the light source control unit has a correction function for correcting an illuminance signal from the illuminance meter according to a reference illuminance detected by the reference illuminance meter.
(2) Irradiating exposure light through a plurality of masks arranged close to a substrate transported in a predetermined direction along a direction intersecting the predetermined direction, and patterning the plurality of masks on the substrate A method of controlling a proximity scan exposure apparatus that exposes,
A step of detecting the illuminance of the light by an illuminometer provided in a plurality of irradiation units that are respectively disposed on the plurality of masks and irradiate the exposure light;
Detecting a reference illuminance of each irradiation unit by moving between the irradiation units;
Correcting the illuminance signal from the illuminance meter according to the reference illuminance detected by the reference illuminance meter;
Controlling the power of the irradiation unit according to an illuminance signal from the illuminometer;
A control method for a proximity scan exposure apparatus, comprising:

According to the proximity scan exposure apparatus of the present invention and the control method thereof,
By correcting each illuminometer with the reference illuminometer, variations are suppressed, and by making the illuminance between the irradiation sections constant, exposure unevenness can be eliminated and exposure can be performed with high accuracy.

It is a top view of the proximity scanning exposure apparatus which is embodiment of this invention. It is a front view of the proximity scan exposure apparatus in FIG. It is a block diagram which shows the structure of the light source control part of the proximity scan exposure apparatus which concerns on this invention. It is a flowchart for demonstrating the control method of the proximity scan exposure apparatus which concerns on this invention.

  Embodiments of a proximity scan exposure apparatus and an exposure method according to the present invention will be described below in detail with reference to the drawings.

  First, a schematic configuration of the proximity scan exposure apparatus 1 of the present embodiment will be described. As shown in FIGS. 1 and 2, the scan exposure apparatus 1 of the present embodiment floats and supports a substrate W, and transports the substrate W in a predetermined direction (X direction in FIG. 1), and a plurality of substrate transport mechanisms 10. A plurality of mask holding portions (six on the left and right sides in the embodiment shown in FIG. 1) that hold the masks M and are arranged in two rows in a staggered manner along a direction (Y direction in FIG. 1) that intersects a predetermined direction. 11, a mask driving unit 12 that drives the mask holding unit 11, a plurality of irradiation units 14 that are arranged above the plurality of mask holding units 11 and irradiate exposure light, and each operating part of the scan exposure apparatus 1 And a control unit 15 for controlling the movement of the camera.

  The substrate transport mechanism 10 includes a floating unit 16 provided in a region for transporting the substrate W in the X direction, that is, a region below the plurality of mask holders 11 and a region extending from the bottom region to both sides in the X direction. And a substrate driving unit 17 that holds the one side in the Y direction (the upper side in FIG. 1) and conveys it in the X direction. The levitation unit 16 includes a plurality of exhaust air pads 20 and intake / exhaust air pads 21 respectively provided on a plurality of frames 19, and the exhaust air pads 20 and the intake / exhaust air pads 21 are provided via pumps (not shown) and solenoid valves (not shown). Air is exhausted or sucked and exhausted from the exhaust air pad 21. As shown in FIG. 1, the substrate drive unit 17 includes a suction pad 22 that holds one end of the substrate W that is levitated and supported by the levitating unit 16, and includes a motor 23, a ball screw 24, and a nut (not shown). The substrate W is transported in the X direction along the guide rail 26 by the ball screw mechanism 25. As shown in FIG. 2, the plurality of frames 19 are arranged via another level block 28 on a device base 27 installed on the ground via the level block 18. Further, the substrate W may be transported by a linear servo actuator instead of the ball screw mechanism 25.

  The mask drive unit 12 is attached to a frame (not shown), and is attached to the X direction drive unit 31 that drives the mask holding unit 11 along the X direction, and the tip of the X direction drive unit 31. Is attached to the tip of the Y direction drive unit 32, and the mask holding unit 11 is rotationally driven in the θ direction (around the horizontal plane of the X and Y directions). A θ-direction drive unit 33 and a Z-direction drive unit 34 that is attached to the tip of the θ-direction drive unit 33 and drives the mask holding unit 11 in the Z direction (vertical direction of the horizontal plane composed of the X and Y directions). Accordingly, the mask holding unit 11 attached to the tip of the Z direction driving unit 34 can be driven in the X, Y, Z, and θ directions by the mask driving unit 12. Note that the order of arrangement of the X, Y, θ, and Z direction drive units 31, 32, 33, and 34 can be changed as appropriate.

  Further, as shown in FIG. 1, a mask changer 2 capable of simultaneously exchanging the masks M of the mask holding portions 11a and 11b between the carry-in side and carry-out side mask holding portions 11a and 11b arranged in two rows in a staggered manner. Is arranged. The used or unused mask M transported by the mask changer 2 is transferred to and from the mask stockers 3 and 4 by the loader 5. The mask M is pre-aligned by a mask pre-alignment mechanism (not shown) during the transfer between the mask stockers 3 and 4 and the mask changer 2.

As shown in FIG. 2, the plurality of irradiation units 14 arranged on the top of each mask holding unit 11 includes a light source 6, a mirror 7, an optical integrator (not shown), a shutter (not shown), and the like. As the light source 6, for example, an ultrahigh pressure mercury lamp, a xenon lamp, or an ultraviolet light emitting laser that irradiates exposure light EL including ultraviolet light is used.
Further, each illuminance meter 50 for detecting the illuminance is provided on the mirror 7 of each irradiation unit 14.

  Such a proximity scan exposure apparatus 1 floats and holds the substrate W by the air flow of the exhaust air pad 20 and the intake / exhaust air pad 21 of the levitation unit 16, and adsorbs one end of the substrate W by the substrate drive unit 17 in the X direction. Transport to. Then, the exposure light EL from the irradiation unit 14 is irradiated to the substrate W positioned below the mask holding unit 11 through the mask M, and the pattern of the mask M is transferred to the substrate W coated with the photosensitive agent. To do.

As shown in FIG. 3, the control unit 15 is provided with a light source control unit 15 b that controls the power so as to keep the illuminance of the light source 6 of the irradiation unit 14 constant. The light source controller 15b keeps the illuminance constant by controlling the power, mainly voltage, of the light source 6 according to the illuminance signal output from each illuminometer 50.
In addition, each irradiation unit 1 (14a), irradiation unit 2 (14b), irradiation unit 3 (14c)... Irradiation unit N (14N) has a corresponding illuminometer 1 (50a), illuminometer 2 ( 50b), illuminance meter 3 (50c)... Illuminance meter N (50N) are provided, and the illuminance of each irradiation unit 14 is controlled according to each illuminance meter 50.

Further, a reference illuminance meter 60 for measuring the illuminance serving as a reference is connected to the light source control unit 15a.
The reference illuminometer 60 is provided on the mask M side surface of the mask changer 2. The mask changer 2 moves between the irradiation units 14 to detect the reference illuminance of the irradiation units 14. That is, the illuminance of each irradiation unit 14 is detected by one reference illuminometer 60.
The reference illuminometer 60 is movable from the installation position 60a to the installation position 60b. After detecting the illuminance on one side (left side in FIG. 2) of the irradiation unit 14 arranged in a staggered pattern, the other side (in FIG. 2) Illuminance measurement on the right side) is possible.
Alternatively, a plurality of reference illuminometers 60 may be prepared, and each may be placed at the installation position 60a and the installation position 60b.

Further, unlike the illuminance meter 14 provided in the vicinity of the light source 6, the reference illuminance meter 60 measures the illuminance near the mask M, so that it is closer to the illuminance used for actual exposure. Therefore, when the reference illuminance and the value of each illuminance meter are greatly different, it can be corrected to the side close to the actual exposure illuminance.
Further, the reference illuminance meter 60 is formed so as to be movable in the transport direction of the substrate W, and the illuminance distribution at each point in one mask M can also be measured.
Instead of providing the reference illuminometer 60 in the mask changer 2, a separate moving mechanism may be provided.

The light source controller 15a is provided with a correction function 15b. The correction function 15 b corrects the illuminance signal from the illuminance meter 50 according to the reference illuminance detected by the reference illuminance meter 60. Specifically, the illuminance signal from each illuminance meter 50 is compared with the reference illuminance (signal) detected by the reference illuminance meter 60, and if the values are different, correction is performed to replace the illuminance signal with the reference illuminance signal. Do.
In this case, the replacement may be performed in a predetermined data table, but the illuminance meter 50 and the reference illuminance meter 60 are measured a plurality of times (each two or more points) while changing the set illuminance, and an approximate expression (correction formula) ) To calculate the correction value.

Hereinafter, specific processing of illuminance correction will be described with reference to the flowchart of FIG.
A case will be described in which the set illuminance is changed, two points are measured, and correction is performed using the approximate expression.

  First, the reference illuminance meter 60 moves below the irradiation unit 1 (14a) according to a command from the control unit 15 to the moving mechanism 70 of the mask changer 2 (step 1). Then, provisional output setting 1 is performed from the light source control unit 15a to the irradiation unit 1 (14a) (step 2), and the exposure light EL is emitted from the light source 6 with provisional output (step 3). Thereafter, the shutter is opened (step 4), and the exposure light EL is actually applied to the mask M.

  Here, illuminance measurement is performed by the illuminometer 1 (50a) (step 6), and an illuminance signal is output to the light source controller 15a. At the same time or thereafter, the reference illuminance is measured by the reference illuminance meter 60, and a reference illuminance signal is output to the light source controller 15a. Then, the shutter is closed (step 7), and the irradiation of the exposure light EL from the light source 6 is stopped (step 8).

Then, provisional output setting 2 is performed from the light source control unit 15a to the irradiation unit 1 (14a) (Step 9), and the processing from Step 3 to Step 8 is repeated (Step 10 to Step 15).
Thereafter, the two illuminance values of the illuminometer 1 (50a) and the reference illuminometer (60) are compared (step 16). If the values are different, a correction formula is determined (step 17).
Further, the reference illuminometer (60) moves to the next irradiation unit 2 (14b), and the above processing is repeated.

After all the measurements of each irradiation unit 14 are completed, an initial output setting for performing actual exposure is performed from the light source control unit 15a to the irradiation unit 1 (14a) (step 20). Light EL is irradiated (step 3). Thereafter, the shutter is opened (step 22), and the exposure light EL is actually applied to the mask M.
Then, each illuminance meter 50 again compares the value with the reference illuminance meter 60 in the same manner as when setting the temporary output, and if the values are correct, the exposure operation is actually started. After that, see paragraph [0014].
Further, if the values are different, the processing from step 1 to step 18 is repeated in the irradiation unit 14 having a different value.
The reference illuminance may be measured at the time of replacement of the light source 6 that is periodically generated, or may be measured every predetermined period such as every day or every week as necessary.

  As described above, according to the proximity scan exposure apparatus 1 and the control method thereof according to the present embodiment, unevenness in exposure is eliminated by making the illuminance between the light sources 6 constant by suppressing variations in the illuminance meters 50, Exposure can be performed with high accuracy.

In addition, this invention is not limited to the said embodiment, A change, improvement, etc. are possible suitably.
In the above embodiment, each illuminance unit 50 is provided in each irradiating unit 14, but power control is performed by periodically detecting the reference illuminance with the reference illuminance meter 60 without providing each illuminance meter 50. May be.
Further, it is applicable not only to the proximity scanning exposure apparatus but also to the step type proximity exposure apparatus.

DESCRIPTION OF SYMBOLS 1 Proximity scanning exposure apparatus 10 Substrate conveyance mechanism 11 Mask holding part 12 Mask drive part 14 Irradiation part 15 Control part 15a Light source control part 15b Correction function 50 Illuminance meter 60 Reference illuminance meter 70 Movement mechanism EL Exposure light M Mask W Color filter substrate (substrate)

Claims (2)

Proximity for irradiating exposure light through a plurality of masks arranged close to a substrate transported in a predetermined direction along a direction intersecting the predetermined direction to expose the patterns of the plurality of masks on the substrate A scanning exposure apparatus,
A plurality of irradiation units respectively disposed on top of the plurality of masks and irradiating the exposure light;
An illuminometer provided in the irradiating unit for detecting the illuminance of the light;
A light source control mechanism for controlling the power of the irradiation unit according to an illuminance signal from the illuminometer,
A reference illuminometer that detects a reference illuminance of each irradiation unit by moving between the irradiation units, and
The proximity scanning exposure apparatus, wherein the light source control mechanism has a correction function for correcting an illuminance signal from the illuminance meter according to a reference illuminance detected by the reference illuminance meter. Proximity for irradiating exposure light through a plurality of masks arranged close to a substrate transported in a predetermined direction along a direction intersecting the predetermined direction to expose the patterns of the plurality of masks on the substrate A method for controlling a scanning exposure apparatus, comprising:
A step of detecting the illuminance of the light by an illuminometer provided in a plurality of irradiation units that are respectively disposed on the plurality of masks and irradiate the exposure light;
Detecting a reference illuminance of each irradiation unit by moving between the irradiation units;
Correcting the illuminance signal from the illuminance meter according to the reference illuminance detected by the reference illuminance meter;
Controlling the power of the irradiation unit according to an illuminance signal from the illuminometer;
A control method for a proximity scan exposure apparatus, comprising:

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