JP2006047881A - Aligner and method for manufacturing layered substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aligner which can control a patterning dimension of a layered substrate having a plurality of layers formed on a substrate by exposure to be within a specified range, and to provide a method for manufacturing a layered substrate. <P>SOLUTION: In the manufacturing process of a TFT substrate, an exposure magnification for a first layer is determined, and a pattern for the first layer is transferred by exposure based on the determined exposure magnification. In the steps of transferring patterns for the second and succeeding layers, the exposure magnification is corrected based on the extraction and contraction amount of the substrate. When the lamination accuracy between a completed TFT substrate and a CF substrate is out of a predetermined range, a magnification correction value for the first layer to retain the lamination accuracy within the predetermined is calculated, and the consecutive TFT substrate is manufactured based on the calculated magnification correction value. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an exposure apparatus and a method for manufacturing a laminated substrate in which a plurality of layers are transferred onto a substrate by an exposure process.

  In recent years, liquid crystal display devices have been widely used as display devices in monitors, projectors, televisions, mobile phones, and the like.

  A liquid crystal display device generally includes a liquid crystal panel in which a TFT substrate on which a TFT (thin film transistor) array is formed and a CF substrate on which a color filter (CF) is formed are bonded, and a liquid crystal material is enclosed between the substrates. ing.

  Then, the transmittance (or reflectance) of each pixel in the liquid crystal panel is changed by controlling a drive signal applied to the TFT as a switching element, and the intensity of light from the light source irradiated on the liquid crystal panel is modulated. The image and characters are displayed in color by emitting through the color filter. That is, by applying a driving voltage corresponding to an image signal to pixels regularly arranged in a matrix, the optical characteristics of the liquid crystal layer in each pixel are changed, and the light incident on the liquid crystal layer is converted into a color filter. The images and characters are displayed in color by being emitted through the screen.

  In addition, in a liquid crystal panel, a TFT array formed on a TFT substrate is used as a switching element in order to apply an independent driving voltage to each pixel. The TFT substrate is applied to each pixel electrode in addition to the TFT array. Wiring or the like for supplying a driving voltage is provided.

  By the way, in order to improve the main performance such as the aperture ratio and the brightness of the liquid crystal panel, it is necessary to improve the bonding accuracy (overlap accuracy) between the TFT substrate and the CF substrate. For this reason, it is necessary to match the size (patterning dimension) of the TFT array or wiring formed on the TFT substrate with the size of the color filter formed on the CF substrate with high accuracy.

  However, in the TFT substrate manufacturing process, generally, a laminated structure composed of a plurality of layers is formed by repeating an exposure process, a heat treatment process, and the like, and the expansion and contraction of the substrate occurs in the formation process of each layer. The patterning dimensions such as may differ from the dimensions of the color filter on the CF substrate.

  FIG. 7 is a flowchart showing an outline of a manufacturing process of a conventional liquid crystal panel. As shown in this figure, a TFT substrate formed through other process steps such as an exposure process and a heat treatment process using TFT masks 1, 2, 3, 4, 5,. , 3, 4,... Are bonded to a CF substrate formed through other process steps such as an exposure process and a heat treatment process, and an evaluation and confirmation of a bonding shift amount is performed. If correction is necessary as a result of the evaluation and confirmation of the shift amount, a correction operation for correcting the shift amount is performed.

Conventionally, the following three methods are conceivable for the correction work for accurately matching the patterning dimension on the TFT substrate and the dimension of the color filter on the CF substrate.
(1) A method of correcting the mask by repeatedly evaluating the exposure magnification at the time of formation of each layer in each TFT substrate manufacturing process,
(2) A method for correcting the size of part or all of the color filter side mask in accordance with the created TFT substrate,
(3) Three methods of correcting part or all of the size of the TFT side mask in accordance with the color filter substrate.

  However, in the first method, it is necessary to perform redesign of design data and exposure pattern for each layer formation process on the TFT substrate by trial and error, and there is a problem that it takes a very long time. . That is, if the exposure data of the first layer (first layer) is changed, correction confirmation work is required for each layer after the second layer (second layer), which requires a lot of time and labor.

  Therefore, for example, as disclosed in Patent Document 1, in an exposure apparatus that transfers a pattern formed on a mask to a substrate via a projection optical system, the substrate is expanded or contracted based on an alignment mark formed on the substrate. A technique for calculating the amount and changing the magnification of the projection optical system based on the calculated amount of expansion / contraction of the substrate has been developed.

  However, when this technique is used, the patterning dimension (exposure magnification) of each layer is corrected based on the amount of expansion / contraction of the substrate, so that each layer can be accurately stacked, but the patterning dimension of the TFT substrate after forming the laminated structure Is determined by the amount of expansion / contraction of the substrate in the formation process of each layer, and may not match the size of the CF substrate.

  The third method, like the first method, requires large-scale confirmation work, requires time and labor, and has a problem that a large amount of cost is required to recreate the mask.

For this reason, conventionally, the second method, that is, correction of the bonding accuracy between the TFT substrate and the CF substrate is performed by correcting the size of the color filter in accordance with the produced TFT substrate.
Japanese Patent Laid-Open No. 9-306819 (published on November 28, 1997)

  However, when correcting the bonding accuracy between the TFT substrate and the CF substrate by correcting the size of the color filter according to the TFT substrate produced as in the prior art, a mask used in the color filter manufacturing process is expensive. Therefore, there is a problem that the manufacturing cost of the liquid crystal panel increases.

  In particular, when a collective exposure type exposure apparatus with excellent throughput is used to manufacture a color filter, the cost for re-forming the mask is very high due to the large size of the mask. In recent years, the substrate size has been increased, and the cost of the mask used in the color filter manufacturing process tends to further increase.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an exposure apparatus that can adjust the patterning dimension of a laminated substrate in which a plurality of layers are formed by exposure processing on a substrate within a predetermined range. And it is providing the manufacturing method of the said laminated substrate.

  In order to solve the above problems, the exposure apparatus of the present invention, a projection optical means for irradiating the incident light onto the substrate at a predetermined projection magnification, an expansion / contraction amount detection means for detecting the expansion / contraction amount of the substrate, A magnification correction unit that corrects the projection magnification of the projection optical unit, and a magnification calculation unit that calculates a magnification correction amount of the projection optical unit based on the detected expansion / contraction amount of the substrate, and a pattern formed on the mask An exposure apparatus for forming a plurality of layers on the substrate by transferring them onto the substrate via a projection optical means, wherein the patterning dimensions of the plurality of layers after formation are set to a value within a predetermined range. Therefore, an initial layer magnification calculating means for calculating a projection magnification when the first layer is formed on the substrate is provided.

  According to the above configuration, when the first layer magnification calculating unit forms the first layer on the substrate such that the patterning dimensions of the plurality of layers after the formation have values within a predetermined range. Calculate the projection magnification. That is, the first layer magnification calculating means is formed on the substrate so that the patterning dimensions of the plurality of layers after formation are within a predetermined range in consideration of the projection magnification in the transfer of the second and subsequent layers. The projection magnification of the first layer to be calculated is calculated.

  Thereby, a laminated substrate in which the patterning dimension of each layer is a value within a predetermined range can be formed. In addition, for example, when forming a TFT substrate used for a liquid crystal display element in which a TFT substrate (laminated substrate) and a CF substrate are bonded using the exposure apparatus of the present invention, the TFT substrate and the CF substrate are highly accurate. Can be realized. In this case, since it is not necessary to recreate the color filter forming mask, which has been conventionally performed to correct the bonding accuracy between the TFT substrate and the CF substrate, the manufacturing cost of the liquid crystal display element can be reduced.

  The exposure apparatus of the present invention includes a substrate holding means for holding the substrate, and moves along a coordinate system that is orthogonal to the optical axis direction of the projection optical means and has two directions as axes. An exposure apparatus for sequentially transferring a pattern formed on a mask to a plurality of regions existing on the substrate, wherein the patterning dimensions of the plurality of layers after the formation are within a predetermined range. Therefore, the initial layer movement amount calculating means for calculating the movement amount of the substrate stage when the first layer is sequentially transferred to the plurality of regions, and the expansion / contraction of the substrate detected by the expansion / contraction amount detection means. A movement amount calculating means for calculating the movement amount of the substrate stage when the second and subsequent layers are sequentially transferred to the plurality of regions based on the amount may be provided.

  According to the above configuration, the first layer movement amount calculating means sequentially transfers the first layer to the plurality of regions in order to set the patterning dimensions of the plurality of layers after formation to a value within a predetermined range. The movement amount of the substrate stage is calculated when the movement amount calculating unit sequentially transfers the second and subsequent layers to the plurality of regions based on the expansion / contraction amount of the substrate. Is calculated.

  As a result, a laminated substrate composed of a plurality of layers in which the pattern formed on the mask is sequentially transferred to a plurality of regions existing on the substrate is formed so that the patterning dimension of each layer is a value within a predetermined range. it can.

  In order to solve the above-described problems, the method for manufacturing a laminated substrate of the present invention irradiates the light transmitted through the mask onto the substrate at a predetermined projection magnification, thereby forming a pattern formed on the mask on the substrate. A method for manufacturing a laminated substrate, wherein a plurality of layers are formed on the substrate by a transfer step, wherein a patterning dimension of the plurality of layers after formation is a value within a predetermined range. The step of setting the projection magnification for transferring the first layer onto the substrate, the step of transferring the first layer at the set projection magnification, and the amount of expansion / contraction of the substrate A step of detecting, a step of calculating a correction amount of a projection magnification for transferring the second and subsequent layers based on the detected expansion / contraction amount of the substrate, and a projection corrected based on the calculated magnification correction amount Transfer the second and subsequent layers at a magnification It is characterized in that it comprises that the step.

  In the above manufacturing method, the projection magnification of the first layer formed on the substrate is set so that the patterning dimensions of the plurality of layers after the formation have values within a predetermined range. That is, in consideration of the projection magnification in the transfer of the second and subsequent layers, the first layer formed on the substrate is formed such that the patterning dimensions of the plurality of layers after the formation are within a predetermined range. Set the projection magnification. The projection magnification in the second and subsequent layers is corrected based on the detected amount of expansion / contraction of the substrate. Thereby, a laminated substrate in which the patterning dimension of each layer is a value within a predetermined range can be formed.

  Further, in the manufacturing method of the present invention, the substrate is moved along a coordinate system that is orthogonal to the optical axis direction of the light irradiated on the substrate and has two directions as axes. A method of manufacturing a laminated substrate in which a pattern formed on a mask is sequentially transferred to a plurality of regions existing on the substrate so that patterning dimensions of the plurality of layers after the formation are within a predetermined range. In addition, the movement amount of the substrate when sequentially transferring the first layer to the plurality of regions is set, and the second and subsequent layers are set to the plurality of regions based on the detected expansion / contraction amount of the substrate. You may make it set the movement amount of the said board | substrate at the time of transferring sequentially.

  According to the above manufacturing method, the amount of movement of the substrate when the first layer is sequentially transferred to the plurality of regions is such that the patterning dimensions of the plurality of layers after formation are within a predetermined range. The amount of movement of the substrate when the second and subsequent layers are sequentially transferred to the plurality of regions is set based on the amount of expansion / contraction of the substrate.

  As a result, the pattern formed on the mask is sequentially transferred to a plurality of regions existing on the substrate, and the laminated substrate is composed of a plurality of layers so that the patterning dimension of each layer is a value within a predetermined range. Can be manufactured.

  The exposure apparatus of the present invention calculates an initial layer magnification for calculating a projection magnification of a first layer formed on the substrate so that patterning dimensions of the plurality of layers after formation are within a predetermined range. Calculation means are provided. Further, in the method for manufacturing a laminated substrate according to the present invention, the projection magnification for transferring the first layer onto the substrate so that the patterning dimensions of the plurality of layers after the formation have values within a predetermined range. Set.

  Therefore, it is possible to form a laminated substrate in which the patterning dimension of each layer is a value within a predetermined range. In addition, for example, when forming a TFT substrate used for a liquid crystal display element in which a TFT substrate (laminated substrate) and a CF substrate are bonded using the exposure apparatus of the present invention, the TFT substrate and the CF substrate are highly accurate. Can be realized. In this case, since it is not necessary to recreate the color filter forming mask, which has been conventionally performed to correct the bonding accuracy between the TFT substrate and the CF substrate, the manufacturing cost of the liquid crystal display element can be reduced.

  An embodiment of the present invention will be described. FIG. 2 is a block diagram showing a schematic configuration of the exposure apparatus 1 according to the present embodiment. FIG. 3 is a plan view schematically showing a schematic configuration of the exposure apparatus 1. The exposure apparatus 1 used in the present embodiment is a stepper (exposure apparatus) that sequentially transfers a pattern formed on a mask to a plurality of regions existing on a substrate, and magnification correction (projection magnification) for the second and subsequent layers. The shot interval (correction of the movement amount of the substrate stage 11) is automatically corrected (corrected by the main control unit 31) with the correction amount calculated based on the expansion / contraction amount of the substrate.

  As shown in FIG. 2, the exposure apparatus 1 includes a substrate stage 11, a substrate holder 12, an illuminance sensor 13, a projection lens unit 14, an integrator 15, a shutter 16, a light source 17, a reticle holder (mask holder) 18, and a stage position sensor 23. , A reticle holder position sensor 24, an alignment microscope 26, an input unit 27, and a control unit 30.

  As shown in FIG. 3, the substrate stage 11 is disposed on the lower side (light irradiation direction) of the projection lens unit 14 in the optical axis direction.

  A substrate holder 12 that holds the substrate 100 is provided on the substrate stage 11. An illuminance sensor 13 that measures the illuminance of light projected by the projection lens unit is embedded in a part of the substrate stage 11.

  A reticle holder 18 for holding a reticle (mask) 101 is arranged on the upper side in the optical axis direction of the projection lens unit 14 (upstream side in the light irradiation direction). Further, on the upper side in the optical axis direction, a condenser lens 19 and a mirror are arranged. 20 is arranged. An alignment microscope 26 is provided in the vicinity of the projection lens unit 14.

  A half mirror 21, a shutter 16, and a mirror 22 are arranged in the optical axis direction bent by the mirror 20 (upstream side in the light irradiation direction). A light source 17 is arranged in the optical axis direction further bent by the mirror 22 (upstream side in the light irradiation direction). As a result, the light emitted from the light source 17 is projected onto the substrate 100 via the mirror 22, the shutter 16, the half mirror 21, the mirror 20, the condenser lens 19, the reticle 101, and the projection lens unit 14. The pattern of the reticle 101 illuminated with the irradiation light (exposure light) from the light source 17 is imaged on the surface of the substrate 100 by the projection lens unit 14.

  Further, the half mirror 21 reflects a part of the irradiated light without transmitting it, and the reflected and bent light is irradiated to the integrator 15.

  The integrator (integrated light quantity meter) 15 calculates the integrated light quantity of light emitted from the light source 17 to the substrate 100 via the projection lens unit 14, and transmits the calculation result to the main control unit 31.

  The input unit 27 receives an instruction from the user to the exposure apparatus 1 and transmits it to the control unit 30. The input unit 27 includes a plurality of operation keys. However, the present invention is not limited to this. For example, the input unit 27 includes an interface that can be connected to an external device such as a personal computer, and receives an instruction from the user via the connected external device. Also good.

  The control unit 30 includes a main control unit 31, a stage drive unit 32, a projection lens drive unit 33, a reticle holder drive unit 34, a shutter drive unit 35, a light source drive unit 36, and a storage unit 37.

  The main controller 31 is a central part of the exposure apparatus 1 that controls all operations in the exposure apparatus 1. In addition, the main control unit 31 stores information and programs for controlling each unit, setting information input via the input unit 27, and the like in the storage unit 37, and can read them out in a timely manner. Yes.

  The substrate stage drive unit 32 moves the substrate stage 11 in accordance with an instruction from the main control unit 31 and turns ON / OFF the adsorption holding of the substrate 100 by the substrate holder 12. More specifically, the substrate stage 11 is movable along two directions (X direction and Y direction) orthogonal to the optical axis direction (Z direction) of the projection lens unit 14. Note that the position of the substrate stage 11 in the movement coordinate system with the X and Y directions as axes is always measured by the stage position sensor 23, and the substrate stage drive unit 32 receives instructions from the main control unit 31 and the stage. The substrate stage 11 is driven and controlled based on the measurement value obtained by the position sensor 23. The stage position sensor 23 is not particularly limited. For example, a laser interferometer may be used.

  Further, the substrate holder 12 sucks and holds the substrate 100 by vacuuming (reducing pressure) a plurality of holes or grooves provided on the contact surface with the substrate 100. The switching of OFF is controlled by the substrate stage driving unit 32 in accordance with an instruction from the main control unit 31 as described above. The area of receiving and contacting the substrate 100 as a design surface (area to be sucked and held) is not particularly limited, but the exposure apparatus 1 performs so-called full-surface suction that attracts about 20% or more of the substrate surface of the substrate 100. Thus, the substrate 100 can be accurately and accurately held.

  The projection lens driving unit 33 drives the projection lens unit 14 according to an instruction from the main control unit 31 and controls the projection magnification of the irradiation light on the substrate 100. More specifically, the projection lens unit 14 can adjust (correct) the projection magnification by a magnification adjustment mechanism controlled by the projection lens driving unit 33. The configuration of the magnification adjustment mechanism is not particularly limited. For example, the projection magnification can be changed by changing the refractive index of the space by changing the pressure of the gas sealed between the lens elements constituting the projection lens unit 14. Or a mechanism for changing the projection magnification by moving a specific lens element constituting the projection lens unit 14 in the optical axis direction. A method of calculating the magnification correction amount will be described later.

  The reticle holder drive unit 34 adjusts (corrects) the position of the reticle holder 18 in accordance with an instruction from the main control unit 31. More specifically, the reticle holder 18 moves in two directions (X direction and Y direction) orthogonal to the optical axis direction (Z direction) of the projection lens unit 14 and a rotation direction (θ direction) about the optical axis direction. It is possible. A reference mark 25 for measuring an alignment mark (not shown) formed on the reticle 101 is provided on the substrate stage 11 at the same height as the surface of the substrate 100. The reference mark 25 has a light source (not shown) incorporated therein.

  When the reticle 101 is mounted on the reticle holder 18, the main control unit 31 causes the substrate stage driving unit 32 to scan the alignment mark formed on the reticle 101 with the light beam from the reference mark 25 via the projection lens unit 14. Thus, the movement of the substrate stage 11 is controlled. The main control unit 31 then moves the coordinate system of the substrate stage 11 based on the amount of transmitted light that has passed through the reticle 101 received by an alignment sensor (not shown) and the output of the stage position sensor 23 that measures the position of the substrate stage 11. The position of the alignment mark at is calculated. Further, the main control unit 31 controls the reticle holder driving unit 34 based on the calculated position of the alignment mark in the movement coordinate system of the substrate stage 11 to drive the reticle holder 18 in the X, Y, and θ directions, and the reticle. 101 is aligned.

  The light source driving unit 36 switches ON / OFF of the light source 17 in accordance with an instruction from the main control unit 31.

  The shutter drive unit 35 opens and closes the shutter 16 in accordance with instructions from the main control unit 31. The main control unit 31 calculates a shutter time (exposure time) based on the integrated light amount measured by the integrator 15 so that a predetermined resist line width can be obtained, and sends the shutter drive unit 35 based on the calculated shutter time. The shutter 16 is opened and closed.

  In the exposure apparatus 1, the main control unit 31 detects the illuminance of irradiation light (exposure light) irradiated through the projection lens unit 14 by the illuminance sensor 13 provided in the substrate stage 11 as necessary. Based on the detection result, the integrated light quantity detected by the integrator 15 is corrected to calculate the shutter time. Thereby, in the exposure apparatus 1, even when the detection accuracy of the integrator 15 is deteriorated, it is possible to perform the exposure process with an appropriate shutter time.

  Here, an exposure magnification correction amount calculation method in the exposure apparatus 1 will be described. An alignment microscope 26 (see FIGS. 2 and 3) having an optical axis at a predetermined angle with respect to the optical axis of the projection lens is provided in the vicinity of the projection lens unit 14. The alignment microscope 26 measures a plurality of alignment marks (not shown) formed on the substrate 100 placed on the substrate stage 11.

  The main control unit 31 uses the measurement result of the alignment microscope 26 and is necessary for matching the exposure area of the substrate 100 exposed through the projection lens unit 14 with the area to be exposed on the substrate 100. The amount of movement of the substrate stage 11 is calculated. Further, the main control unit 31 calculates the amount of expansion / contraction of the substrate 100 by measuring a plurality of alignment marks formed on the substrate 100, and further calculates the magnification correction value of the projection lens unit 14 based on the amount of expansion / contraction. calculate.

  The reference mark 25 formed on the substrate stage 11 is provided with a mark for correcting the position of the substrate stage 11 as well as a mark for correcting the position of the reticle 101. Therefore, if the position correction mark of the substrate stage 11 provided on the reference mark 25 is measured by the alignment microscope 26, the position correction mark of the reticle 101 provided on the reference mark 25 and the substrate stage 11 are The relationship between the reticle 101 and the alignment microscope 26 can be understood from the design position difference from the position correction mark. Therefore, the positional relationship between the reticle 101 and the substrate 100 is also known.

  The exposure apparatus 1 can correct the exposure magnification in consideration of the amount of expansion / contraction even when the substrate 100 is expanded / contracted in the exposure process of each layer by such correction processing.

  Next, a method for manufacturing the liquid crystal display element according to the present embodiment, which is performed using such an exposure apparatus 1, will be described.

  First, a manufacturing method of a TFT substrate will be described with reference to FIG. First, the main control unit 31 receives a magnification setting for the first layer exposure process on the TFT substrate, which is input from the user via the input unit 27 (S1). In the subsequent processing, a coordinate system based on the set magnification of the first layer is used as a reference coordinate system. Further, for example, the first-layer reticle (mask) may be prototyped in advance and corrected based on the prototype result.

  Next, the main control unit 31 performs position correction (alignment) of the reticle holder 18 by the method described above (S2).

  When the substrate 100 is placed on the substrate holder 12, the main control unit 31 controls the substrate stage driving unit 32 to start attracting and holding the substrate 100 by the substrate holder 12 (S <b> 3).

  Thereafter, the main control unit 31 controls each unit of the exposure apparatus 1 to transfer the first-layer reticle pattern to the substrate 100 (S4). That is, the main control unit 31 controls the substrate stage driving unit 32 to move the substrate stage 11 by a set movement amount (stepping operation), and also has a light source driving unit 36, a shutter driving unit 35, and a projection lens driving unit 33. , The substrate 100 is exposed by a step-and-repeat operation, and the first-layer reticle pattern is transferred onto the substrate 100.

  Thereby, a plurality of shot regions (transfer regions) are formed in a predetermined region on the substrate 100. In this case, a continuous pattern is formed in adjacent shot regions. In addition, a plurality of alignment marks are formed on the substrate 100 during the exposure of the first layer. For example, a plurality of alignment marks may be provided separately for each of the position measurement in the X direction and the position measurement in the Y direction.

  Next, the main control unit 31 controls each unit of the exposure apparatus 1 to perform development, etching, and other process processes (S5). By this process, the substrate 100 is expanded and contracted, and the size of the first shot area is also expanded and contracted.

  Next, the main control unit 31 measures the positions of a plurality of alignment marks formed on the substrate 100 (S6). More specifically, the main control unit 31 monitors the substrate stage 11 on which the substrate 100 is held while monitoring the detection results of the alignment microscope 26 and the stage position sensor 23 while the substrate stage driving unit 32 moves the substrate stage 11 to X. By driving in the direction and the Y direction, the positions of a plurality of alignment marks formed on the substrate 100 are measured.

  Next, the main control unit 31 calculates each correction parameter based on the measured value of the alignment mark (S7). As a calculation method, for example, a least square method may be used. That is, various correction parameters (projection magnification, shot interval, amount of movement of the substrate stage 11) are obtained by associating the design coordinate position of each alignment mark with the actual coordinate position to be aligned by the least square method or the like. Etc.) may be calculated.

  Next, the main control unit 31 performs magnification correction (projection magnification and shot interval correction) of the projection lens unit 14 for the next exposure process based on the calculated correction parameter (S8).

  Then, based on the corrected magnification and movement amount, the second layer exposure process is performed, the reticle pattern is transferred (S9), and development, etching and other process processes are performed (S10).

  Next, the main control unit 31 determines whether or not to form a next layer (S11). And when forming the next layer, the process similar to the process after S6 performed to the 2nd layer is performed sequentially about the subsequent layers.

  On the other hand, when the next layer is not formed in S11, the main control unit 31 calculates a bonding error (bonding accuracy) between the formed TFT substrate and the CF substrate (S12). For example, the size of the color filter on the CF substrate to be bonded to the TFT substrate is previously input via the input unit 27 and stored, and the patterning size of the TFT substrate formed by the main control unit 31 and the size of the color filter are set. A comparison error may be calculated by comparison.

Next, the main control unit 31 determines whether or not the bonding error is within a predetermined range (S13). In order to appropriately form TFTs on the substrate, the bonding error is preferably within ± 20 ppm. (As a result of repeated trial production, it was confirmed that if the bonding error was within ± 20 ppm, it could be produced by the production method of the present invention.)
If the bonding error is within a predetermined range, the main control unit 31 ends the correction process. In this case, the formation of the TFT substrate after the next time may be formed based on the condition set last time in S1.

  On the other hand, when the bonding error is not within the predetermined range, the main control unit 31 calculates the exposure magnification of the first layer for setting the bonding error within the predetermined range (or the minimum value) (S14). ). That is, the main control unit 31 sets a bonding error of the TFT substrate to be formed next within a predetermined range (or a minimum value) based on the patterning dimension of the formed TFT substrate and the amount of expansion / contraction of the substrate during the exposure processing of each layer. The first layer magnification correction value is calculated.

  Then, based on the calculated magnification correction value of the first layer, the processing from S1 is performed to manufacture the next TFT substrate. Thereby, the patterning dimension of the TFT substrate after the formation can be set to a value at which the bonding error with the CF substrate becomes a value within a predetermined range.

  As described above, in the present embodiment, the exposure apparatus that automatically corrects the exposure magnification according to the expansion / contraction amount of the substrate is used, and the exposure magnification and the substrate stage 11 in the exposure process of the first layer of the TFT substrate (laminated substrate) are used. Is set so that the patterning dimension of each layer in the TFT substrate after formation becomes a value within a predetermined range, and the exposure magnification is automatically corrected for the second and subsequent layers according to the amount of expansion and contraction of the substrate. Thereby, a TFT substrate having a desired patterning dimension can be created, and high-precision bonding between the TFT substrate and the CF substrate can be easily realized.

  Therefore, it is not necessary to recreate the color filter forming mask, which has been conventionally performed to correct the bonding accuracy between the TFT substrate and the CF substrate, so that the manufacturing cost of the liquid crystal display element can be reduced. In particular, in the manufacturing process of a color filter, when using an exposure apparatus that performs batch exposure using a mask formed at the same size as the image to be transferred, the mask size is large, so that the pattern size of the mask is changed. Since the cost is very high, the manufacturing cost can be greatly reduced by correcting the size on the TFT substrate side as in this embodiment.

  In the above description, based on the patterning dimension of the formed TFT substrate, the main control unit 31 sets the magnification correction value for the first layer so that the bonding error of the TFT substrate to be formed next is within a predetermined range. Was calculated and set as the magnification correction value for the first layer for the exposure processing of the next TFT substrate. However, the present invention is not limited to this. For example, the user may calculate the magnification correction value for the exposure processing of the first layer, or set the value based on an empirical rule. Even in this case, it is possible to realize high-precision bonding between the TFT substrate and the CF substrate simply by setting the magnification correction value for the first layer, and it is not necessary to change the pattern dimensions of the color filter forming mask. The manufacturing cost of the element can be reduced. Further, the main control unit 31 calculates a magnification correction value for the first layer so that the bonding error of the TFT substrate to be formed next is within a predetermined range based on the patterning dimension of the formed TFT substrate. The result may be presented to the user by, for example, a display means (not shown), and the user may set the first layer magnification correction value for the next TFT substrate based on the result.

  In this embodiment, the exposure apparatus 1 that sequentially transfers the pattern formed on the mask to a plurality of regions existing on the substrate has been described. However, the exposure apparatus to which the present invention can be applied is not limited to this. Any exposure apparatus that can correct the exposure magnification in accordance with the amount of expansion / contraction of the substrate may be used. For example, for each layer formed on the substrate, the pattern formed on the mask may be collectively transferred at a predetermined magnification. .

  Although the exposure apparatus 1 according to the present embodiment calculates the exposure magnification based on the substrate expansion / contraction amount, the configuration of the exposure apparatus 1 is not limited to this. For example, in addition to the above-described configuration, a means for measuring environmental conditions (temperature, gas composition, density, pressure, etc.) in the chamber is provided, and the exposure magnification is adjusted in consideration of these conditions in addition to the expansion / contraction amount of the substrate. The correction amount and the movement amount of the substrate stage 11 may be calculated.

  Moreover, the manufacturing method of the laminated substrate of this invention can also be expressed as shown in FIG. 4, for example. In the method shown in this figure, first, a TFT substrate formed through other process steps such as an exposure process and a heat treatment process using the TFT masks 1, 2, 3, 4, 5,. , 2, 3, 4,... Are bonded to a CF substrate formed through other process steps such as an exposure process and a heat treatment process, and the amount of bonding deviation is evaluated and confirmed.

  For the evaluation and confirmation of the deviation amount, the deviation amount between the TFT substrate and the CF substrate is measured at each measurement point on the bonded substrates.

  Then, four components (correction values) of a shift component, a rotation component, a magnification component, and a residual distortion component are calculated from the measured deviation amount.

  Thereafter, a shift component and a rotation component are extracted from the calculated four components, and these components are corrected by a bonding apparatus (not shown). And about the board | substrate which correct | amended with the bonding apparatus and bonded together, the deviation | shift amount of bonding is again evaluated and confirmed.

  If a predetermined bonding accuracy cannot be obtained by the correction of the bonding apparatus, a magnification component correction value is extracted, and the magnification component is fed back to the exposure data of the first layer (TFT mask 1). That is, the shot interval (scaling) and lens projection magnification (magnification) are corrected in the exposure process of the first layer.

  FIG. 5A to FIG. 5C are plan views for explaining methods of shot interval correction and lens projection magnification correction.

  FIG. 5A is a plan view showing a shot region in the substrate 100 before performing the first layer exposure process and the subsequent process steps.

  FIG. 5B corresponds to the substrate 100 that has undergone elongation after the size and position of each shot region has changed due to the elongation of the substrate 100 as a result of performing the first-layer exposure process and subsequent process steps. It is a top view for demonstrating the process which correct | amends a shot space | interval and lens projection magnification so that it may.

  An alternate long and short dash line in FIG. 5B indicates a part of the shot area corresponding to the coordinate system in FIG. The shot interval is corrected according to the elongation of the substrate 100 so that the shot region is moved to a position corresponding to the elongation of the substrate 100. The position of each shot area after correcting the shot interval is represented by a solid line.

  Next, the lens projection magnification of the projection lens is corrected so that the reticle pattern is transferred to each shot area with a size corresponding to the elongation of the substrate 100. A broken line in FIG. 5B indicates a shot area after the lens projection magnification is corrected.

  By correcting the shot interval and the lens projection magnification, the reticle pattern can be transferred to an appropriate shot area corresponding to the elongation of the substrate 100 as shown in FIG.

  FIG. 6 is a graph showing a bonding error between the TFT substrate and the CF substrate before and after the magnification correction of the first layer. As shown in this figure, the bonding error after the magnification correction of the first layer was 5 ppm better than before the magnification correction.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately changed within the scope of the claims are also included in the technical scope of the present invention.

  The present invention is an exposure apparatus in which a plurality of layers are formed on a substrate by an exposure process, and can be applied to an exposure apparatus capable of changing the exposure magnification and a method for manufacturing the laminated substrate using the exposure apparatus.

It is the flowchart which showed the flow of the process in the exposure apparatus concerning one Embodiment of this invention. It is a block diagram which shows schematic structure of the exposure apparatus concerning one Embodiment of this invention. It is a top view which shows schematic structure of the exposure apparatus concerning one Embodiment of this invention. It is a flowchart which shows the manufacturing method of the multilayer substrate concerning one Embodiment of this invention. (A) is a top view which shows the shot area | region in the board | substrate before performing a process process. (B) is a top view for demonstrating the process which correct | amends a shot space | interval and a lens projection magnification so that it may respond | correspond to the board | substrate which the elongation produced as a result of performing the shot area | region and process process shown to (a). . (C) is a plan view showing a shot area after correcting the shot interval and lens projection magnification shown in (b). It is a graph which shows the bonding error of a TFT substrate and CF substrate. It is a flowchart which shows the manufacturing method of the conventional liquid crystal panel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exposure apparatus 11 Substrate stage 12 Substrate holder (substrate holding means)
14 Projection lens unit (projection optical means)
16 Shutter 17 Light source 18 Reticle holder 25 Reference mark (Expansion / contraction amount detection means)
26 Alignment microscope (Expansion / contraction amount detection means)
30 control unit 31 main control unit (expansion / contraction amount detection means, magnification calculation means, initial layer magnification calculation means, initial layer movement amount calculation means, movement amount calculation means)
32 substrate stage drive unit 33 projection lens drive unit (magnification correction means)
34 reticle holder driving unit 35 shutter driving unit 36 light source driving unit 100 substrate 101 reticle (mask)

Claims (4)

Projection optical means for irradiating the incident light onto the substrate at a predetermined projection magnification, expansion / contraction amount detection means for detecting the expansion / contraction amount of the substrate, magnification correction means for correcting the projection magnification of the projection optical means, and A magnification calculating unit that calculates a magnification correction amount of the projection optical unit based on the detected expansion / contraction amount of the substrate, and transferring the pattern formed on the mask onto the substrate via the projection optical unit, An exposure apparatus for forming a plurality of layers on the substrate,
There is provided an initial layer magnification calculating means for calculating a projection magnification when forming a first layer on the substrate so that patterning dimensions of the plurality of layers after formation are set to values within a predetermined range. An exposure apparatus characterized by comprising: A substrate stage having a substrate holding means for holding the substrate is provided on the mask, the substrate stage moving along a coordinate system that is orthogonal to the optical axis direction of the projection optical means and that has two directions orthogonal to each other. An exposure apparatus for sequentially transferring the formed pattern to a plurality of regions existing on the substrate,
First layer for calculating the amount of movement of the substrate stage when the first layer is sequentially transferred to the plurality of regions in order to set the patterning dimensions of the plurality of layers after formation to a value within a predetermined range. A movement amount calculating means;
A movement amount calculating means for calculating a movement amount of the substrate stage when the second and subsequent layers are sequentially transferred to the plurality of regions based on the expansion / contraction amount of the substrate detected by the expansion / contraction amount detection means; The exposure apparatus according to claim 1, comprising: an exposure apparatus. A laminate in which a plurality of layers are formed on the substrate by a transfer process in which the pattern formed on the mask is transferred onto the substrate by irradiating the substrate with light transmitted through the mask at a predetermined projection magnification. A method for manufacturing a laminated substrate for manufacturing a substrate,
Setting a projection magnification for transferring the first layer onto the substrate such that the patterning dimensions of the plurality of layers after formation are values within a predetermined range;
Transferring the first layer at the set projection magnification;
Detecting the amount of expansion and contraction of the substrate;
Calculating a correction amount of the projection magnification for transferring the second and subsequent layers based on the detected expansion / contraction amount of the substrate;
And a step of transferring the second and subsequent layers at the projection magnification corrected based on the calculated magnification correction amount. The pattern formed on the mask is moved by moving the substrate along a coordinate system that is orthogonal to the optical axis direction of the light irradiated onto the substrate and that is orthogonal to each other. A method of manufacturing a laminated substrate that sequentially transfers to a plurality of regions existing on a substrate,
Setting the amount of movement of the substrate when sequentially transferring the first layer to the plurality of regions so that the patterning dimensions of the plurality of layers after formation are within a predetermined range;
4. The stacked substrate according to claim 3, wherein the amount of movement of the substrate when sequentially transferring the second and subsequent layers to the plurality of regions is set based on the detected expansion / contraction amount of the substrate. Production method.

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