JP2013044798A - Proximity exposure device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a proximity exposure device in which a sensor for detecting a substrate position can be arranged at an optional position and the throughput can be improved.SOLUTION: A mask stage 10 includes reflection type sensor 20 for detecting an end of a substrate W held by substrate supporting units 31a and 31b. While travel of linear motors 39 and 46 is controlled on the basis of the detection of the end of the substrate W by the reflection type sensor 20, the substrate W is moved to an exposure position OEP at a speed slower than a travel speed between a light reception region EP and a loading region WP.

Description

  The present invention relates to a proximity exposure apparatus, and more particularly to a proximity exposure apparatus used when manufacturing a liquid crystal display panel.

  The proximity exposure device is used to manufacture color filters and the like of flat panel display devices such as liquid crystal display panels and portable device displays, and emits light for pattern exposure through the mask while the mask and the substrate are brought close to each other. Irradiate to expose and transfer the mask pattern to the substrate.

  In recent years, a liquid crystal display panel that forms a small touch panel, such as a smartphone, has increased the number of times that the display is touched. Therefore, the display includes a glass substrate such as aluminosilicate glass (chemically tempered glass) that can withstand repeated stress Is required. However, when such a glass substrate is chamfered after heat treatment, the heat treatment does not reach the inside of the substrate and may not be able to withstand repeated stress. For this reason, when exposing such a liquid crystal display, it is preferable to perform an exposure process after performing a heat treatment on the size of the substrate mounted on the actual product. When exposing such a substrate, use a mask of almost the same size as the substrate, place a plurality of substrates on the substrate stage, grasp the positional information of the substrate on the substrate stage, and align with the mask. However, it is preferable to perform batch exposure.

  Conventionally, as an alignment method of a mask and a substrate, a method of controlling a wafer stage every time a mask having a different pattern is changed (see, for example, Patent Document 1), an alignment mark on an exposure mask, and a relative relationship between device regions. It is known that the actual positional deviation is measured by the rotation amount and shift amount of the device region with respect to the alignment mark, and feedback to alignment correction at the time of exposure is easily performed (for example, see Patent Document 2). Yes.

  Conventionally, as the position detection of the substrate mounted on the substrate stage, in the loading area where the substrate is loaded or unloaded on the substrate stage, the light projecting unit of the light projecting / receiving sensor is respectively provided above and below the frame of the exposure apparatus. A light receiving unit is arranged, and the light projected from the light projecting unit and irradiated to the end of the substrate is received and detected by the light receiving unit.

JP 2007-335545 A JP 2002-196476 A

  However, such a light projecting / receiving sensor requires a relatively wide space in the vertical direction of the substrate to be detected, and the installation position of the light emitting / receiving sensor is restricted, so that it can be installed at any position of the exposure apparatus. However, there was a problem that the installation position was restricted. For this reason, in the twin stage type exposure apparatus, the sensor is disposed in the vicinity of the substrate loading area, in other words, in an area relatively distant from the exposure area. After the substrate position is detected, the substrate is transported to the exposure position while managing the position of the substrate stage. However, if the substrate is transported at high speed, it is difficult to manage the position of the substrate stage with high accuracy. There was a problem that throughput decreased.

  The alignment method described in Patent Document 1 controls the wafer stage, not the wafer position information, and the alignment method described in Patent Document 2 grasps the substrate position information. Therefore, it was not specifically described how to move the camera or how to move the substrate stage.

  The present invention has been made in view of the above-described problems, and it is an object of the present invention to provide a proximity exposure apparatus in which a substrate position sensor can be installed at an arbitrary position and throughput can be improved.

The above object of the present invention can be achieved by the following constitution.
(1) a mask stage having a mask holding unit for holding a mask and a mask driving unit for driving the mask holding unit;
An exposure area having a substrate holding section for holding a substrate as an exposure material and a substrate driving section for driving the substrate holding section, and an loading area for loading or unloading the substrate. A substrate stage movable between
An irradiation device for irradiating the substrate with light for pattern exposure through the mask;
A proximity exposure apparatus that exposes and transfers a pattern of the mask onto the substrate in a state in which the mask and the substrate are placed close to each other with a predetermined exposure gap.
The mask stage is provided with a reflective sensor that detects an end portion of the substrate held by the substrate holding unit when the substrate holding unit is located in the exposure region.
The substrate driving unit is a linear motor capable of managing the amount of movement of the substrate holding unit,
Based on the detection of the edge of the substrate by the reflective sensor, the substrate driving unit is controlled at a moving speed slower than the moving speed between the exposure area and the loading area while managing the moving amount of the substrate driving part. A proximity exposure apparatus that is driven to move the substrate holder to an exposure position.
(2) a mask stage having a mask holding unit for holding a mask and a mask driving unit for driving the mask holding unit;
An exposure area having a substrate holding section for holding a substrate as an exposure material and a substrate driving section for driving the substrate holding section, and an loading area for loading or unloading the substrate. A substrate stage movable between
An irradiation device for irradiating the substrate with light for pattern exposure through the mask;
A proximity exposure apparatus that exposes and transfers a pattern of the mask onto the substrate in a state in which the mask and the substrate are placed close to each other with a predetermined exposure gap.
The mask stage is provided with a reflective sensor that detects an end portion of the substrate held by the substrate holding unit when the substrate holding unit is located in the exposure region.
The mask driving unit is a linear motor capable of managing the amount of movement of the mask holding unit,
Based on the detection of the edge of the substrate by the reflective sensor, the mask driving unit is driven to move the mask holding unit to an exposure position while managing the movement amount of the mask driving unit. A proximity exposure apparatus.

  According to the proximity exposure apparatus of the present invention, since the sensor for detecting the edge of the substrate is constituted by a reflective sensor, the space of the mask is difficult to install on the mask stage where the space sensor is difficult to install. It is possible to install a sensor for detecting the end. Further, since the reflective sensor is disposed on the mask stage, the substrate stage is moved at high speed between the loading area and the exposure area, and the detection signal is detected after the reflective sensor detects the edge of the substrate. Since the substrate stage is moved to the exposure position at a slow movement speed while managing the movement amount of the substrate driving unit based on the above, the substrate transfer time can be shortened and the throughput is improved.

  In addition, a reflective sensor for detecting the edge of the substrate is disposed on the mask stage, and the mask driving unit is configured to detect the edge of the substrate conveyed from the loading area to the exposure area based on the detection signal detected by the reflective sensor. Since the mask driving unit is driven while the movement amount is managed and the mask holding unit is moved to the exposure position, the substrate stage can be moved between the loading region and the exposure region at a high speed. Throughtime is shortened and throughput is improved.

It is a schematic plan view which shows the whole structure of the proximity exposure apparatus which concerns on this invention. It is a front view of the proximity exposure apparatus shown in FIG. FIG. 3 is a side view of the substrate stage shown in FIG. 2. It is a flowchart which shows the operation | movement procedure of exposure.

  Embodiments of a proximity exposure apparatus according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic plan view showing the overall configuration of a proximity exposure apparatus according to the present invention, FIG. 2 is a front view of a main part of the proximity exposure apparatus, and FIG. 3 is a side view of a substrate stage.

  1 to 3, the proximity exposure apparatus PE includes a mask stage 10, a first substrate stage 11, a second substrate stage 12, an irradiation apparatus 13, a pre-alignment unit 14, a first substrate loader 15, and a second substrate. A loader 16, a mask loader 17, and a mask aligner 18 are provided, and each is placed on a base 21.

  The mask stage 10 is supported by a plurality of support columns 22 provided on a rectangular stage base 23 disposed on a base 21 and is disposed above the stage base 23. The plurality of support columns 22 form a space above the stage base 23 so that the first and second substrate stages 11 and 12 can move in the Y direction (left and right direction in FIG. 1) and advance below the mask stage 10. doing.

  The mask stage 10 has a rectangular opening 25a at the center, and is driven by a mask driving unit (not shown) with respect to the frame of the mask stage 10 so as to be supported so that its position can be adjusted in the X, Y, and θ directions. 25. A plurality of suction holes 25b are formed in the lower surface of the mask holding part 25, and the mask M having a pattern to be exposed faces the opening 25a and is brought into the mask holding part 25 through the suction holes 25b by vacuum suction. Retained. The mask stage 10 includes a mask alignment camera (not shown) that detects the position of the mask M with respect to the mask holding unit 25 and a gap sensor (not shown) that detects a gap between the mask M and the substrate W. ) And are provided.

  A plurality of reflective sensors 20 are disposed on the lower surface of the mask stage 10 so as to face the substrate W mounted on the first and second substrate stages 11 and 12. The reflective sensor 20 detects the reflected light of the light irradiated toward the substrate W from above, and detects the presence or absence of the substrate W, that is, the end portion of the substrate W. The reflective sensor 20 is composed of one Y-axis reflective sensor 20a disposed along the X-axis direction and two X-axis reflective sensors 20b and 20c disposed along the Y-axis direction. The The Y-axis reflective sensor 20a detects the end of the substrate W held in the substrate holding portions 31a and 31b in the Y-axis direction, and the X-axis reflective sensor 20b and 20c in the X-axis direction of the substrate W. Detect the edge. Thereby, the position of the substrate W in the X, Y, and θ directions can be known.

  As shown in FIGS. 2 and 3, the first and second substrate stages 11 and 12 have substrate holding portions 31a and 31b, respectively, for holding a substrate W as a material to be exposed. Further, below the first and second substrate stages 11 and 12, a substrate is provided with a Y-axis table 33, a Y-axis feed mechanism 34, an X-axis table 35, an X-axis feed mechanism 36, and a Z-tilt adjustment mechanism 37. Substrate stage moving mechanisms 32 and 32 as drive units are provided, respectively. Each of the substrate stage moving mechanisms 32 and 32 feeds and drives the first and second substrate stages 11 and 12 in the X direction and the Y direction with respect to the stage base 23, and also finely closes the gap between the mask M and the substrate W. The first and second substrate stages 11 and 12 are finely moved and tilted in the Z-axis direction so as to be adjusted.

  Specifically, the Y-axis feed mechanism 34 includes a linear guide 38 disposed between the stage base 23 and the Y-axis table 33, and a Y-axis linear motor 39. In the linear guide 38, two guide rails 40 are arranged in parallel along the Y-axis direction on the stage base 23, and a slider 41 attached to the back surface of the Y-axis table 33 is a rolling element (not shown). ). The Y-axis linear motor 39 includes a stator 43 that is fixed on the stage base 23 along the Y-axis direction, and a mover 44 that is disposed opposite to the stator 43 and attached to the back surface of the Y-axis table 33. Have. The two Y-axis tables 33 and 33 are each driven by a Y-axis linear motor 39 and supported so as to be movable along the two guide rails 40 in the Y-axis direction.

  The Y-axis linear motor 39 can manage the amount of movement of the mover 44, that is, the substrate holders 31a and 31b in the Y-axis direction. Specifically, by checking a control device (not shown) that transmits a drive signal to the Y-axis linear motor 39 at predetermined time intervals, the position of the Y-axis linear motor 39 (substrate holding portions 31a and 31b) is determined. I can know. More specifically, when reading the position of the Y-axis linear motor 39 at a time interval of 10 ms, for example, when the Y-axis linear motor 39 is moving at a high speed of 1 m / sec, the position accuracy is 10 mm. The position of the Y-axis linear motor 39 can be known, and the position of the Y-axis linear motor 39 can be known with a positional accuracy of 10 μm when moving at a low speed of 1 mm / sec.

  The X-axis feed mechanism 36 has the same configuration, and as shown in FIG. 3, a linear guide 45 and an X-axis linear motor 46 are provided between the Y-axis table 33 and the X-axis table 35. Two guide rails 47 are arranged in parallel along the X-axis direction on the Y-axis table 33, and a slider 48 attached to the back surface of the X-axis table 35 is provided via a rolling element (not shown). It is straddled. The X-axis linear motor 46 includes a stator 50 that is fixed to the Y-axis table 33 along the X-axis direction, and a mover 51 that is disposed opposite to the stator 50 and attached to the back surface of the X-axis table 35. Have. The two X-axis tables 35 and 35 are each driven by an X-axis linear motor 46 and supported so as to be movable along the two guide rails 47 in the X-axis direction. Further, the X-axis linear motor 46 can manage the amount of movement of the substrate holders 31 a and 31 b in the X-axis direction, similarly to the Y-axis linear motor 39.

  On the other hand, the Z-tilt adjustment mechanism 37 includes a movable wedge mechanism that is a combination of a motor, a ball screw, and a wedge, and the ball screw shaft 53 is driven to rotate by a motor 52 installed on the upper surface of the X-axis table 35. At the same time, the ball screw nut 54 is assembled to the wedge-shaped moving body, and the slope of the wedge is engaged with the slope of the wedge 55 protruding from the lower surfaces of the substrate stages 11 and 12.

  When the ball screw shaft 53 is driven to rotate, the ball screw nut 54 is finely moved horizontally in the X-axis direction, and the wedge-shaped moving body in which the horizontal fine movement is assembled makes it possible to perform high-precision vertical fine movement. Converted. Two of these movable wedge mechanisms are installed on one end side in the X-axis direction and one on the other end side (not shown) in total, and each is driven and controlled independently. Note that the combination of this motor and the ball screw may be replaced with a linear motor.

  As a result, the Y-axis feed mechanism 34 should place the substrates W held by the substrate holding portions 31a and 31b of the substrate stages 11 and 12 individually at the exposure position OEP arranged at the lower position of the mask stage 10. The first substrate stage 11 is moved in the Y-axis direction along the guide rail 40 between the first loading region WP1 and the exposure region EP, and the second substrate stage 12 is guided between the second loading region WP2 and the exposure region EP. 40 along the Y-axis direction. In addition, the X-axis feed mechanism 36 and the Y-axis feed mechanism 34 move the substrate holding portions 31a and 31b in the exposure area EP in the X and Y directions with respect to the mask M so that the first and second substrate stages 11, 12 is moved to the exposure position OEP.

  As shown in FIG. 2, the irradiation device 13 is disposed above the opening 25a of the mask holding unit 25 and is a light source for ultraviolet irradiation, such as a high-pressure mercury lamp, a concave mirror, an optical integrator, a plane mirror, a spherical mirror, and an exposure control It is configured with a shutter or the like. The irradiation device 13 irradiates the substrate W held on the substrate holding portions 31a and 31b of the first and second substrate stages 11 and 12 moved to the exposure position OEP with light for pattern exposure through the mask M. As a result, the mask pattern of the mask M is exposed and transferred onto the substrate W.

  The pre-alignment unit 14 includes a mask M prior to the substrate W transported from the substrate cassettes 70A and 70B installed outside the base 21 being supplied to the first substrate stage 11 or the second substrate stage 12. The position of the substrate W with respect to is pre-aligned, and is arranged on the front side of the mask stage 10 in the figure.

  The first substrate loader 15 is disposed on the right side of the pre-alignment unit 14 in FIG. 1, holds the substrate W supplied to the first substrate stage 11, transports it to the pre-alignment unit 14, and is a pre-aligned substrate W is transferred from the pre-alignment unit 14 to the first substrate stage 11, and the substrate W after exposure transfer on the first substrate stage 11 located at the first standby position WP1 is transferred to the substrate cassette 70A. The second substrate loader 16 is disposed on the left side of the pre-alignment unit 14 in FIG. 1 and performs the same operation as the first substrate loader 15 on the second substrate stage 12.

  Further, the mask loader 17 and the mask aligner 18 are disposed opposite to the first substrate loader 15 with respect to the first substrate stage 11. The mask loader 17 serving as a loader robot carries the mask M from a mask cassette 91 provided outside the base 21 and conveys the mask M pre-aligned by the mask aligner 18 to the first substrate stage 11. The mask M is supplied to the mask stage 10 by the first substrate stage 11.

  Next, the operation procedure of the proximity exposure apparatus PE will be described with reference to the flowchart shown in FIG. First, in step S1, the substrate W is mounted on the substrate stage 11 (12) in the loading area WP. In order to move the substrate W to the exposure area EP in step S2, the substrate stage 11 (12) is moved at a high speed (for example, 1 m / sec) by the Y-axis linear motor 39, and is placed on the mask stage 10 in step S3. The reflection sensor 20 detects the end of the substrate W mounted on the substrate stages 11 and 12.

  In step S4, it is determined whether or not the position of the substrate W detected by the reflective sensor 20 is within the exposure possible range (exposure area EP). Specifically, it is recognized that the end of the substrate W is within the exposure possible range by being detected by the reflective sensor 20. Here, if the substrate W is not within the exposure range, that is, if the end of the substrate W cannot be detected by the reflective sensor 20, the substrate stage 11 (12) has not reached the lower side of the mask stage 10. Since the determination is made, the process returns to step S2, the substrate stage 11 (12) is moved at a high speed by the Y-axis linear motor 39, and the loop in which the reflection sensor 20 detects the end of the substrate W is repeated. The reflective sensor 20 is for detecting that the substrate W has reached the exposure possible range, and its detection accuracy is relatively coarse.

  When the reflection sensor 20 detects the end of the substrate W (the position of the substrate W is within the exposure range), in step S5, the Y-axis and X-axis linear motors 39 and 46, which can manage the movement amount, The position at that time is read, and it is determined whether or not the substrate W is within the exposure possible range. Here, it is possible to determine whether or not the exposure is within the exposure range using, for example, an alignment mark. If it is determined that the substrate W is not within the exposure range, the substrate stage 11 (12) is moved at a slow speed (for example, 1 mm / sec) by the Y-axis and X-axis linear motors 39 and 46 in step S6. .

  Note that when the mask M and the substrate W are aligned by moving the mask M instead of moving the substrate stage 11 (12), the mask stage 10 (mask holding unit 25) is a mask driving unit. It is moved by a linear motor (not shown).

  Here, the substrate stage 11 (12) is moved at a high speed until the reflective sensor 20 detects the end of the substrate W, and after the reflective sensor 20 detects the end of the substrate W, the slow speed. For example, when reading the positions of the linear motors 39 and 46 at a time interval of 10 ms, the reading position accuracy when moving at a high speed of 1 m / sec is 10 mm, and 1 mm / The reading position accuracy when moving at a low speed of sec is 10 μm. That is, until the substrate W reaches the exposure area EP (below the mask stage 10), even if the position accuracy is rough, the substrate W is moved at a high speed that can be transported to the exposure area EP in a short time. To move at low speed.

  If it is determined in step S5 that the substrate W is within the exposure range, the process proceeds to step S7, and the reflection sensor 20 detects the end of the substrate W again to check whether it is within the exposure range. . Here, since the substrate W should be within the exposure range, if it is not within the exposure range, it is determined that the linear motor is in an abnormal state. Repeat.

  If it is confirmed in step S7 that the exposure is within the range that can be exposed, an exposure process is performed in step S8, and it is determined in step S9 whether or not the processing of all the planned substrates W has been completed. If an unprocessed substrate W still remains, the position of the substrate stage 11 (12) is read from the linear motors 39 and 46 in step S10, the value is returned to the position where the substrate W is mounted, and then step S11. Thus, the positions of the linear motors 39 and 46 are fed back to the control unit of the reflective sensor 20. As a result, the position of the substrate stage 11 (12) is returned to the same position as when the first substrate W is mounted.

  Next, in step S12, the second substrate W is mounted on the substrate stage 11 (12) in the loading area WP. Thereafter, the same operation is performed until there is no unprocessed substrate W. When the exposure processing for all the substrates W is completed, the exposure processing is terminated in step S13.

  As described above, according to the proximity exposure apparatus PE of the present embodiment, the sensor for detecting the end portion of the substrate W is constituted by the reflective sensor 20, so that the space is narrow and the installation of the projecting and emitting sensor is performed. It is possible to install a sensor for detecting the end of the substrate W even on the mask stage 10 which is difficult to perform. Further, since the reflective sensor 20 is disposed on the mask stage 10, the substrate stages 11 and 12 are moved at high speed between the loading area WP and the exposure area EP, and the reflective sensor 20 is moved to the end of the substrate W. After detecting the portion, the substrate stages 11 and 12 are moved to the exposure position OEP at a slow movement speed while managing the movement amounts of the Y-axis linear motor 39 and the X-axis linear motor 46 based on the detection signal. Therefore, the substrate transfer time can be shortened and the throughput is improved.

  Further, a reflective sensor 20 for detecting the end of the substrate W is disposed on the mask stage 10, and the detection signal detected by the reflective sensor 20 detects the end of the substrate W transferred from the loading area WP to the exposure area EP. Based on this, the mask driving unit is driven while managing the movement amount of the linear motor, which is a mask driving unit (not shown), and the mask holding unit 25 is moved to the exposure position OEP. The substrate stages 11 and 12 can be moved between the exposure regions EP at a high speed, thereby shortening the substrate transport time and improving the throughput.

In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.

  For example, in the above description, the substrate holders 31a and 31b are moved by the Y-axis linear motor 39 and the X-axis linear motor 46 so that the position of the substrate W is aligned with the mask M. However, the present invention is not limited to this. After the substrate stages 11 and 12 are moved to the exposure region EP, the mask holding unit 25 may be driven by a mask driving unit (linear motor) to align the position of the mask M with the substrate W.

  Further, a plurality of reflective sensors 20 are movably arranged with respect to the mask holding unit 25, and by moving the reflective sensor 20, the edge of the exposure area substrate W is detected by the reflective sensor 20, and the detection signal is detected. Based on this, the substrate holders 31a and 31b can be moved by the Y-axis linear motor 39 and the X-axis linear motor 46 so that the position of the substrate W is aligned with the mask M.

DESCRIPTION OF SYMBOLS 10 Mask stage 11, 12 Substrate stage 13 Irradiation apparatus 20 Reflective sensor 20a Reflective sensor for Y-axis (reflective sensor)
20b, 20c X-axis reflective sensor (reflective sensor)
25 Mask holding part 31a, 31b Substrate holding part 39 Y-axis linear motor (substrate driving part)
46 X-axis linear motor (substrate drive unit)
EP Exposure area M Mask OEP Exposure position PE Proximity exposure device W Substrate (material to be exposed)
WP loading area

Claims (2)

A mask stage having a mask holding unit for holding a mask and a mask driving unit for driving the mask holding unit;
A substrate holding unit for holding a substrate as an exposed material; and a substrate driving unit for driving the substrate holding unit between an exposure region disposed opposite to the mask and a loading region for loading or unloading the substrate. A substrate stage having;
An irradiation device for irradiating the substrate with light for pattern exposure through the mask;
A proximity exposure apparatus that exposes and transfers a pattern of the mask onto the substrate in a state in which the mask and the substrate are placed close to each other with a predetermined exposure gap.
The mask stage is provided with a reflective sensor that detects an end portion of the substrate held by the substrate holding unit when the substrate holding unit is located in the exposure region.
The substrate driving unit is a linear motor capable of managing the amount of movement of the substrate holding unit,
Based on the detection of the edge of the substrate by the reflective sensor, the substrate driving unit is controlled at a moving speed slower than the moving speed between the exposure area and the loading area while managing the moving amount of the substrate driving part. A proximity exposure apparatus that is driven to move the substrate holder to an exposure position. A mask stage having a mask holding unit for holding a mask and a mask driving unit for driving the mask holding unit;
A substrate holding unit for holding a substrate as an exposed material; and a substrate driving unit for driving the substrate holding unit between an exposure region disposed opposite to the mask and a loading region for loading or unloading the substrate. A substrate stage having;
An irradiation device for irradiating the substrate with light for pattern exposure through the mask;
A proximity exposure apparatus that exposes and transfers a pattern of the mask onto the substrate in a state where the mask and the substrate are placed close to each other with a predetermined exposure gap.
The mask stage is provided with a reflective sensor that detects an end portion of the substrate held by the substrate holding unit when the substrate holding unit is located in the exposure region.
The mask driving unit is a linear motor capable of managing the amount of movement of the mask holding unit,
Based on the detection of the edge of the substrate by the reflective sensor, the mask driving unit is driven to move the mask holding unit to an exposure position while managing the movement amount of the mask driving unit. A proximity exposure apparatus.

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