JP2012133122A - Proximity exposing device and gap measuring method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a proximity exposing device and a gap measuring method therefor which automatically measure the height of the upper surface of a substrate and the height of the lower surface of a mask, and can accurately obtain a gap distribution between the substrate and the mask without being affected by skill of an operator.SOLUTION: The proximity exposing device and the gap measuring method therefor include a mask side displacement sensor 31 which is arranged in the side of a mask stage 1 and measures the height Hof the upper surface of a substrate, and a substrate side displacement sensor 15 which is arranged in the side of a work stage 2 and measures the height Hof the lower surface of a mask, and obtains a gap distribution between the substrate W and the mask M based on the height Hof the upper surface of the substrate and the height Hof the lower surface of the mask which have been measured by the mask side displacement sensor 31 and the substrate side displacement sensor 15, respectively.

Description

  The present invention relates to a proximity exposure apparatus and a gap measuring method thereof, and more specifically, proximity exposure transfer of a mask pattern onto a substrate such as a large flat panel display such as a liquid crystal display or a plasma display. The present invention relates to a proximity exposure apparatus suitable for the above and a gap measuring method thereof.

  In the proximity exposure, a translucent substrate (material to be exposed) coated with a photosensitive agent on the surface is held on the work stage of the proximity exposure apparatus, and the substrate is brought close to the mask held on the mask holding frame of the mask stage. The gap between the two is set to several tens of μm to several hundred μm, for example, and the pattern drawn on the mask is exposed and transferred onto the substrate by irradiating the exposure light from the opposite side of the mask with the irradiation device toward the mask. It is what you do.

  By the way, in proximity exposure, there is a method in which the mask is made the same size as the substrate and is exposed in a lump. However, in such a method, when the mask pattern is exposed and transferred onto a large substrate, the mask becomes large and the mask is exposed. This causes problems in terms of the influence on the pattern accuracy due to the bending of the pattern and the cost. For these reasons, conventionally, when a mask pattern is exposed and transferred onto a large substrate, a mask smaller than the substrate is used, and the work stage is moved stepwise relative to the mask, for example, in the Y-axis direction. A so-called stepwise proximity exposure method is used in which a pattern exposure light is irradiated in a state where the mask is placed close to and opposed to the substrate for each step, thereby exposing and transferring a plurality of patterns drawn on the mask onto the substrate. May be used.

  Specifically, first, for example, the position of the mask is adjusted so that the alignment mark on the work stage side and the alignment mark on the mask side are aligned to align the position of the work stage and the mask, and the posture (position of the mask at that time) ) Is stored in a storage device or the like. Next, the substrate mounted on the work stage is brought close to the mask, and the mask pattern is exposed and transferred to the substrate by irradiating light for pattern exposure from the irradiation means toward the mask with the substrate and the mask through a minute gap. To do.

  Next, the substrate is separated from the mask, and in this state, the work stage is sent by one step with respect to the mask. At this time, for example, a work stage feed error occurs due to the accuracy of a linear guide or the like. Therefore, if the next step exposure is performed as it is, the relative position between the exposure pattern of the next step formed on the substrate and the exposure pattern of the first step is shifted. For this reason, before the exposure of the next step, an optical measurement sensor such as a laser interferometer detects a work stage feed error (positional deviation), and the detection result and initial posture information of the mask stored in the storage device. Based on the above, the orientation of the mask is corrected to align the position of the substrate and the mask, and in this state, the exposure of the next step is performed so that the relative position of the individual exposure patterns on the substrate does not shift. I have to.

  In such proximity exposure, in order to expose an exposure pattern with high accuracy, the gap between the substrate and the mask is an important factor together with the positional accuracy of the substrate and the mask. It is necessary to keep the parallelism at several tens of μm to several hundreds of μm. For this reason, at the time of installation of the proximity exposure apparatus or regular maintenance, the gap distribution between the substrate and the mask is measured, and each part is adjusted so that the optimum gap can be maintained during the production of the substrate.

  As a conventional method for measuring the gap distribution, there is a method of measuring the gap in the entire area of the mask by enlarging the movable range of the gap sensor arranged on the mask stage and stroke the gap sensor with a driving mechanism. .

  Further, as a disclosure example regarding the gap between the substrate and the mask, a method for setting the interval between the first and second objects in which the substrate and the mask are set in parallel and at a predetermined interval by a displacement sensor attached to the wafer chuck and the mask chuck. And an apparatus are disclosed (for example, refer to Patent Document 1).

Japanese Patent Laid-Open No. 3-253917

  However, in order to measure the gap distribution between the substrate and the mask with the gap sensor arranged on the mask stage, it is necessary to cover the entire area of the mask, and the movement range of the gap sensor becomes wider as the mask becomes larger, The drive mechanism that supports the gap sensor becomes large. For this reason, there is a problem that not only the detection accuracy is lowered but also the manufacturing cost is increased.

  The method of Patent Document 1 sets a gap during substrate production, and does not consider gap measurement during installation or maintenance of the proximity exposure apparatus prior to substrate production. Further, Patent Document 1 uses a wafer as a target substrate, and cannot be easily applied to gap measurement in the case of using a mask smaller than the substrate, such as exposing a flat panel display panel.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a proximity exposure apparatus capable of automatically obtaining a gap distribution between a substrate and a mask without being affected by an operator's skill, and It is to provide a method for measuring the gap.

The above object of the present invention can be achieved by the following constitution.
(1) A work stage capable of holding and moving a substrate as a material to be exposed, a mask stage disposed opposite to the substrate and capable of holding a mask, and light for pattern exposure to the substrate. Irradiating means for irradiating via, a work stage driving mechanism for moving the work stage in a predetermined direction, and a mask position adjusting means for adjusting the position of the mask with respect to the substrate, the mask and the substrate being A proximity exposure apparatus that exposes and transfers the exposure pattern of the mask to the substrate by the irradiating means in a state of being closely arranged,
A mask side displacement sensor provided on the mask stage side for measuring the height of the upper surface of the substrate;
A substrate side displacement sensor provided on the work stage side for measuring the height of the lower surface of the mask;
Based on the height at a plurality of predetermined positions of the upper surface of the substrate measured by the mask side displacement sensor and the height at a plurality of predetermined positions of the lower surface of the mask measured by the substrate side displacement sensor, Gap calculating means for calculating a gap at an arbitrary position when the mask and the mask are opposed to each other;
A proximity exposure apparatus comprising:
(2) The proximity exposure apparatus according to (1), wherein the mask side displacement sensor is a non-contact sensor.
(3) The gap calculation unit calculates the gap for each of a plurality of exposure areas on the substrate in each shot irradiated with light for pattern exposure by the irradiation unit. The proximity exposure apparatus according to 1.
(4) A work stage capable of holding and moving a substrate as a material to be exposed, a mask stage disposed opposite to the substrate and capable of holding a mask, and light for pattern exposure to the substrate. Irradiating means for irradiating, a work stage driving mechanism for moving the work stage in a predetermined direction, a mask position adjusting means for adjusting the position of the mask with respect to the substrate, and an upper surface of the substrate provided on the mask stage side A mask-side displacement sensor that measures the height of the mask, and a substrate-side displacement sensor that is provided on the work stage side and measures the height of the lower surface of the mask. The exposure pattern of the mask is applied to the substrate by the irradiation unit. A gap measuring method for measuring a gap distribution between the substrate and the mask of a proximity exposure apparatus that performs exposure transfer,
Moving the work stage by the work stage drive mechanism, and measuring the height of a plurality of predetermined positions on the upper surface of the substrate by the mask side displacement sensor;
Moving the work stage by the work stage drive mechanism and measuring the height of a plurality of predetermined positions on the lower surface of the mask by the substrate side displacement sensor;
Based on the height at a plurality of predetermined positions of the upper surface of the substrate measured by the mask side displacement sensor and the height at a plurality of predetermined positions of the lower surface of the mask measured by the substrate side displacement sensor, And a step of calculating a gap at an arbitrary position when the mask faces each other. A gap measuring method for a proximity exposure apparatus, comprising:
(5) In the gap calculating step, from the measured values of the heights at a plurality of predetermined positions on the upper surface of the substrate and the heights at the plurality of predetermined positions on the lower surface of the mask, the gaps other than the height measurement positions are respectively obtained by linear interpolation. The gap measuring method for a proximity exposure apparatus according to (4), further comprising an interpolation processing step for obtaining a height of the upper surface of the substrate and a height of the lower surface of the mask.
(6) In the above (4), the gap calculating step calculates the gap for each of a plurality of exposure areas on the substrate in each shot irradiated with light for pattern exposure by the irradiation unit. The gap measuring method of the proximity exposure apparatus described in 1.

  According to the proximity exposure apparatus and the gap measurement method of the present invention, the operator can obtain the gap distribution between the substrate and the mask at an arbitrary position when the substrate and the mask face each other, particularly at an arbitrary position for each exposure area of each shot. It is possible to obtain automatically without being influenced by the skill of the above, and it is possible to efficiently and accurately adjust the adjustment at the time of installation or maintenance of the exposure apparatus based on the gap distribution. In addition, the height of the upper surface of the substrate and the height of the lower surface of the mask other than the height measurement position can be obtained by linear interpolation from the measured values of the height of the upper surface of the substrate and the height of the lower surface of the mask, and the gap distribution can be determined at any position. Can be sought.

It is a partially broken front view for demonstrating the step type proximity exposure apparatus which concerns on this invention. It is a top view of a board | substrate which shows the measurement position of board | substrate upper surface height. It is a graph which shows the height of each part of a board | substrate upper surface in three dimensions. It is a top view of the mask which shows the measurement position of mask lower surface height. It is a graph which shows the height of each part of a mask lower surface in three dimensions. It is a top view which shows the positional relationship of a board | substrate and a mask at the time of each exposure shot, and a gap display position. It is a graph which shows the height of the board | substrate upper surface and mask lower surface on the yc1 line | wire of FIG. It is a graph which shows the gap distribution of a board | substrate and a mask in three dimensions.

  FIG. 1 is a partially broken front view of a step-type proximity exposure apparatus according to the present invention. As shown in FIG. 1, a step-type proximity exposure apparatus PE uses a mask M smaller than a substrate W as a material to be exposed. M is held by the mask stage 1 and the substrate W is held by the work stage 2, and in this state, the work stage 2 is moved stepwise relative to the mask M in the X-axis direction and the Y-axis direction. The pattern of the mask M is exposed and transferred onto the substrate W by irradiating light for pattern exposure from the irradiation means 3 toward the mask M in a state where the mask M and the substrate W are arranged close to each other and face each other. .

  An X-axis stage feed mechanism 5 for step-moving the work stage 2 in the X-axis direction is installed on the apparatus base 4. The work stage 2 is placed on the X-axis feed base 5 a of the X-axis stage feed mechanism 5. A Y-axis stage feed mechanism 6 for stepping in the axial direction is installed, and a work stage 2 is installed on a Y-axis feed base 6 a of the Y-axis stage feed mechanism 6. On the upper surface of the work stage 2, the substrate W is held in a vacuum sucked state by a work chuck or the like. Further, a substrate side displacement sensor 15 for measuring the lower surface height of the mask M is disposed on the side portion of the work stage 2. Therefore, the substrate side displacement sensor 15 can move in the X and Y axis directions together with the work stage 2.

  Between the Y-axis stage feed mechanism 6 and the work stage 2, since the work stage 2 is moved in the vertical direction, the vertical coarse motion device 7 having a relatively coarse positioning resolution but a large moving stroke and moving speed, and the vertical coarse motion Positioning with high resolution is possible as compared with the apparatus 7, and an up / down fine movement device 8 is installed to finely adjust the gap between the opposing surfaces of the mask M and the substrate W to a predetermined amount by finely moving the work stage 2 up and down. .

  The vertical coarse movement device 7 moves the work stage 2 up and down with respect to the fine movement stage 6b by an appropriate drive mechanism provided on the fine movement stage 6b described later. The stage coarse movement shafts 14 fixed at four positions on the bottom surface of the work stage 2 are engaged with linear motion bearings 14a fixed to the fine movement stage 6b, and are guided in the vertical direction with respect to the fine movement stage 6b. In addition, it is desirable that the vertical coarse motion device 7 has high repeated positioning accuracy even if the resolution is low.

  The vertical fine movement device 8 includes a fixed base 9 fixed to the Y-axis feed base 6a, and a linear guide guide rail 10 attached to the fixed base 9 with its inner end inclined obliquely downward. A ball screw nut (not shown) is coupled to a slide body 12 that reciprocates along the guide rail 10 via a slider 11 straddling the guide rail 10, and an upper end surface of the slide body 12. Is in contact with the flange 12a fixed to the fine movement stage 6b so as to be slidable in the horizontal direction.

  Then, when the screw shaft of the ball screw is rotationally driven by the motor 17 attached to the fixed base 9, the nut, the slider 11 and the slide body 12 are integrally moved along the guide rail 10 in an oblique direction. The flange 12a is finely moved up and down.

  The vertical fine movement device 8 is installed on one end side (left end side in FIG. 1) in the Y-axis direction of the Y-axis feed base 6a and two on the other end side, and a total of three are controlled independently. It is like that. Thereby, the vertical fine movement device 8 increases the heights of the three flanges 12a based on the measurement results of the gap amounts between the mask M and the substrate W at a plurality of positions by the gap sensor constituting the mask side displacement sensor 31 described later. Finely adjust the height and inclination of the work stage 2 by fine adjustment independently.

  On the Y-axis feed base 6a, a bar mirror 19 facing the Y-axis laser interferometer 18 that detects the position of the work stage 2 in the Y direction, and an X-axis laser that detects the position of the work stage 2 in the X-axis direction. A bar mirror (both not shown) facing the interferometer is installed. The bar mirror 19 facing the Y-axis laser interferometer 18 is arranged along the X-axis direction on one side of the Y-axis feed base 6a, and the bar mirror facing the X-axis laser interferometer is located on the Y-axis feed base 6a. It is arranged along the Y-axis direction on one end side.

  The Y-axis laser interferometer 18 and the X-axis laser interferometer are arranged so as to always face the corresponding bar mirrors and supported by the apparatus base 4. Two Y-axis laser interferometers 18 are installed apart from each other in the X-axis direction. The two Y-axis laser interferometers 18 detect the position of the Y-axis feed base 6a and consequently the work stage 2 in the Y-axis direction and the yawing error via the bar mirror 19. In addition, the X-axis laser interferometer detects the position of the X-axis feed base 5a and eventually the work stage 2 in the X-axis direction via the opposing bar mirror.

  Two Y-axis direction position data and X-axis direction position data detection signals obtained during step feed are output to the control device 40, and the control device 40 outputs this detection signal (actual position data) and commanded position data (positioning). A correction amount is calculated on the basis of a difference from the position position data), and the calculation result is output to a driving circuit of a mask position adjusting unit (and vertical fine movement device 8 as necessary), which will be described later. The mask position adjusting means and the like are controlled in accordance with the correction amount to correct the positional deviation and yawing error in the X-axis direction and the Y-axis direction. Thereby, the mask M is aligned so as to correctly face the position of the substrate W to be exposed.

  The mask stage 1 is inserted into the mask frame 24 formed of a substantially rectangular frame and a central opening of the mask frame 24 through a gap, and is movable in the X, Y, and θ directions (in the X and Y planes). The mask frame 24 is held at a fixed position above the work stage 2 by a column 4a protruding from the apparatus base 4. An inwardly extending flange 26 is provided on the lower surface of the central opening of the mask holding frame 25 along the entire circumference of the opening. On the lower surface of the flange 26, a mask M on which a pattern to be exposed is drawn is detachably held via a vacuum suction device (not shown) or the like.

  Above the flange 26, the mask side displacement sensor 31 constituting the gap sensor for measuring the height of the upper surface of the substrate W and measuring the gap between the opposing surfaces of the mask M and the substrate W, and the mask M And an alignment mark (not shown) provided on the substrate W side, or a reference alignment mark (not shown) provided on the work stage 2 or the mask frame 24. Alignment cameras 30 as means are movably arranged.

  The mask-side displacement sensors 31 are arranged at four locations, two at a distance from each other in the X-axis direction, on the inner upper side of the two sides along the X-axis direction of the flange 26. The mask side displacement sensor 31 may be a non-contact type sensor, and an optical type, ultrasonic type or eddy current type gap sensor is applied. The alignment camera 30 is arranged at two locations, one in each of the upper center of the two sides along the X-axis direction of the flange 26, approximately in the center of the X-axis direction, and the image data of these two alignment cameras 30. Based on the above, the control device 40 performs an arithmetic process to detect the amount of plane deviation between the mask M and the substrate W. Then, the mask position adjusting means adjusts the position of the mask M held on the mask holding frame 25 with respect to the substrate W by moving the mask holding frame 25 in the X, Y, and θ directions according to the detected plane deviation amount. Note that the mask side displacement sensor 31 and the alignment camera 30 may be supported so as to be movable with respect to the mask stage 1 via a drive mechanism (not shown).

  The mask position adjusting means is spaced apart from each other in the Y-axis direction on one side along the Y-axis direction of the mask frame 24 and a Y-axis direction driving device (not shown) attached to one side along the X-axis direction of the mask frame 24. And two X-axis direction drive devices (not shown) attached to each other. The Y-axis direction drive device adjusts the Y-axis direction of the mask holding frame 25 by two X-axis direction drive devices. Adjustment of the X-axis direction and θ-axis direction (oscillation around the Z-axis) of the mask holding frame 25 is performed. The masking aperture mechanism 28 includes a light shielding blade (not shown) that limits the exposure range by shielding exposure light in an arbitrary range on the mask M held by the mask holding frame 25 as necessary.

  In the stepped proximity exposure apparatus PE configured as described above, at the time of substrate production, the mask M and the substrate W are arranged close to each other and face each other, and the mask side displacement sensor 31 configured by a gap sensor is used to mask the mask. After measuring the gap G between the M and the substrate W and adjusting the position of the mask M and the substrate W, the pattern M is exposed and transferred onto the substrate W by irradiating light for pattern exposure from the irradiation means 3. To do.

On the other hand, the gap distribution between the mask M and the substrate W is obtained by the following method even before substrate production such as during installation or maintenance. In this case, the gap distribution between the mask M and the substrate is measured in the horizontal plane (XY plane) by measuring the distribution of the height H _m of the lower surface of the mask M and the distribution of the height H _w of the upper surface of the substrate W. The difference between the height H _m of the lower surface of the mask M at the same position and the height H _w of the upper surface of the substrate W is obtained by the control device 40 constituting the gap calculating means.

Specifically, after holding the substrate W on the work stage 2, the work stage 2 is stepped in the X-axis and Y-axis directions by the X-axis stage feed mechanism 5 and the Y-axis stage feed mechanism 6, the height H _w of the top surface of the substrate W with the mask-side displacement sensor 31 is measured over the entire surface of the substrate W. Position measuring the upper surface height H _w of the substrate W, as shown in FIG. 2 is a coordinate system fixed to the device base 4 x _a, y _a, on the z _a-axis coordinates (hereinafter, for convenience, A coordinate The operator inputs matrix points (also referred to as a system) (a ₁₁ (x _a1 , y _a1 ), a ₁₂ (x _a1 , y _a2 ),..., A _nm (x _an , y _am )). It is decided by.

First, the step-type proximity exposure apparatus PE moves the work stage 2 to _select the first measurement point a ₁₁ (of the matrix points (a ₁₁ , a ₁₂ ,..., A _nm ) set by the operator. _xa1 , y _a1 ) are made to _face the mask-side displacement sensor 31, and the height h11 of the upper surface of the first substrate W is measured. Next, the second measurement point a ₁₂ (x _a1 , y _a2 ) is moved to measure the height h ₁₂ of the upper surface of the second substrate W. Thereafter, the same operation is repeated to measure the upper surface height Hw (h ₁₁ , h ₁₂ ,..., H _nm ) over the entire surface of the substrate W. The upper surface height H _w (h ₁₁ , h ₁₂ ,..., H _nm ) of each point of the substrate W measured in this way is represented by a three-dimensional distribution as shown in FIG. A two-dot chain line shown in FIG. 2 indicates a dividing line of each panel of the substrate W when divided exposure described later. The setting of each matrix point is arbitrarily performed by the operator, but may be performed from the relationship with the dividing line of each panel. In addition, the measurement may be performed using any one mask side displacement sensor 31, or a plurality of measurement points may be measured simultaneously using a plurality of mask side displacement sensors 31. Further, the matrix points of the A coordinate system and the B coordinate system may be determined by the operator, or determined by the movement of the mask stage 1 and the work stage 2 automatically. Measure the thickness.

Next, as shown in FIG. 4, x _b is the mask holding frame 25 fixed coordinate system for attracting and holding the mask _M, y _b, on the z _b-axis coordinates (hereinafter, for convenience, referred to as a B coordinate system) The lower surface of the mask M at each matrix point (b ₁₁ (x _b1 , y _b1 ), b ₁₂ (x _b1 , y _b2 ),..., B _nm (x _bn , y _bm )) input by the operator. The height H _m (H ₁₁ , H ₁₂ ,..., H _nm ) is sequentially measured by the substrate side displacement sensor 15 while moving the work stage 2 stepwise in the X-axis and Y-axis directions. The measured lower surface height H _m (H ₁₁ , H ₁₂ ,..., H _nm ) of each point of the mask M is represented by a three-dimensional distribution as shown in FIG.
Incidentally, when measuring the height H _w of the top surface of the substrate W may be performed while holding the mask M on the mask holding frame 25 may be performed in a state of detaching the mask M. Similarly, when measuring the height H _m of the lower surface of the mask M is also may be performed while holding the substrate W on the work stage 2, it may be performed in a state of detaching the substrate W. When measurement is performed with both the substrate W and the mask M held, the distance between the substrate W and the mask M is set to 400 μm or more.

Next, as shown in FIG. 6, the center Om of the mask M and the center Ow of each exposure area WE of the substrate W are made to coincide with each other, and a plurality of areas for dividing and exposing the pattern of the mask M on the substrate W (FIG. 6). Then, 6 areas) are set. Then, for each area (each shot), a matrix point (c ₁₁ ) for which a gap distribution on the xc, yc, and zc axis coordinates (hereinafter also referred to as the C coordinate system for convenience) that is a coordinate system fixed to the mask M is to be obtained. The operator inputs the coordinates of (x _c1 , y _c1 ), c ₁₂ (x _c1 , y _c2 ),..., C _nm (x _cn , y _cm )).

Note that the origin of the A coordinate system, B coordinate system, and C coordinate system may be anywhere as long as the relative positions of the coordinate systems are clear. Namely, each matrix point of each coordinate system _{(a 11, a 12, ···} , a nm, b 11, b 12, ···, b nm, c 11, c 12, ···, c nm) is , And can be converted into the x and y coordinates of each coordinate system. Therefore, for example, the origin of the A coordinate system may be set to the center of the substrate W, and the origin of the B coordinate system and the origin of the C coordinate system may be set to the center of the mask M, respectively. Further, if the matrix point in the B coordinate system and the matrix point in the C coordinate system are the same point, the linear interpolation process in the B coordinate system described later can be omitted.

Then, the control device 40 _converts the coordinates (x _c , y _c ) of the matrix points (c ₁₁ , c ₁₂ ,..., C _nm ) of the _C coordinate system into the coordinates (x _a , y of the A coordinate system). converted to _a), from the distribution of the upper surface height _{H w} of the substrate W on the a coordinate system that is previously measured (see FIG. 3), the matrix points of the C coordinate system _{(c 11, c} 12, · · - _determines the upper surface height _{H w} of the substrate W in _{c nm).}

Similarly, the controller 40 _converts the coordinates (x _c , y _c ) of the matrix points (c ₁₁ , c ₁₂ ,..., C _nm ) of the C coordinate system into the coordinates (x _b , y _b ) of the B coordinate system. ) is converted to, from the lower surface distribution of the height _{H m} of the mask M on the B coordinate system that is previously measured (see FIG. 5), the matrix points of the C coordinate system _{(c 11, c} 12, · · · , C _nm ), the lower surface height H _m of the mask M is obtained.

7, for ease of understanding, a measurement of the bottom surface height H _m of the upper surface height H _w and the mask M of the substrate W is a diagram showing in two dimensions. That is, as an example, the upper surface height H _w of the substrate W along the constant x axis where y _a = y _a1 and the lower surface height H _m of the mask M along the constant x axis where y _b = y _b1 are shown. Yes. And the lower surface height H _m of the mask M, the difference between the upper surface height H _w of the substrate W, the gap G between the mask M and the substrate W.

Matrix points C coordinate system _{(c 11, c 12, ···} , c nm) from the coordinates of the matrix points of the A coordinate system _{(a 11, a 12, ···} , a nm) coordinates, and B coordinates Although the coordinate conversion of the matrix points (b ₁₁ , b ₁₂ ,..., B _nm ) of the system into coordinates can be easily performed, as shown in FIG. 7, the matrix points (c ₁₁ , c _12, · · _·, coordinates _{c nm)} is necessarily matrix point measured the upper surface height _{H w} of the substrate _{W (a 11, a 12,} ···, does not coincide with the coordinates of _{a nm).} Similarly, the coordinates of the matrix points (b ₁₁ , b ₁₂ ,..., B _nm ) at which the lower surface height H _m of the mask M is measured hardly coincide with each other.

The upper surface height H _w of the substrate W and the lower surface height H _m of the mask M at matrix points (c ₁₁ , c ₁₂ ,..., C _nm ) whose coordinates do not coincide with the coordinates of the measurement points are adjacent measurement points. Can be obtained by the linear interpolation processing performed by the control device 40. For example, as shown in FIG. 7, the lower surface height H _m of the mask M in the matrix point c ₂₁ are those lower surface height H _m of the mask M is changed linearly between the matrix point b ₂₁ and b ₃₁ Assuming that, it is obtained by proportional distribution. For even upper surface height H _w of the substrate W, it can be obtained in the same manner. Incidentally, in FIG. 7 has been two-dimensionally displayed clarity, in reality, the upper surface height H _w of the bottom surface height H _m and the substrate W of the mask M, since changes in the xy direction, a three-dimensional The linear interpolation process is performed.

Controller 40 has an upper surface lower surface heights of _{H w} and mask M measured, or each matrix point obtained by linear interpolation _{(c 11, c 12, ···} , c nm) substrate in W and a H _m, determine the gap G as a difference therebetween. FIG. 8 is a gap distribution diagram showing the gap G at each matrix point (c ₁₁ , c ₁₂ ,..., C _nm ) obtained in this way in three dimensions.

  The above-described measurement of the gap distribution is automatically obtained by storing a series of operating procedures in the control device 40 of the stepped proximity exposure apparatus PE and operating the stepped proximity exposure apparatus PE in the gap distribution measurement mode. be able to. Therefore, the gap distribution between the substrate W and the mask M can be automatically obtained without being affected by the skill of the operator.

  Thereby, at the time of installation of the step-type proximity exposure apparatus PE or maintenance, the gap distribution is automatically measured as described above, and after adjusting the mask stage 1 and the work stage 2 from the measurement result, again, By repeatedly measuring the gap distribution, it can be adjusted in a short time and accurately without being affected by the skill of the operator.

  In addition, by comparing the gap distribution measured at the time of installation and maintenance thus obtained with the gap distribution at the time of substrate production, it is possible to obtain the optimum gap that enables high-precision exposure transfer. It can be set prior to production, and productivity can be improved.

As described above, according to proximity exposure apparatus PE of the present embodiment, the mask-side displacement sensor 31 provided on the mask stage 1 side to measure the height H _w of the substrate W upper surface, provided on the work stage 2 side Te substrate side displacement sensor 15 for measuring the height H _m of the mask M lower surface, height and H _w of a plurality of in place of the measured substrate upper _surface, the height H _m of a plurality of predetermined positions of the mask lower surface And a control device 40 that constitutes a gap calculating means for calculating a gap G at an arbitrary position when the substrate W and the mask M are opposed to each other. Therefore, the substrate at an arbitrary position for each exposure area of each shot. The gap distribution between W and mask M can be automatically obtained without being affected by the skill of the operator, and this gap distribution can be adjusted during the installation and maintenance of the proximity exposure apparatus PE. It can be adjusted accurately and efficiently based.

Further, according to the gap measuring method of the proximity exposure apparatus PE of the present embodiment, the work stage 2 is moved, and the substrate upper surface height H _w and the mask lower surface height H _m at a plurality of predetermined positions are respectively set on the mask side. displacement sensor 31, and measured at the substrate side displacement sensor 15, the gap distribution when made to face the substrate W and the mask M, determined based on measurements of the substrate upper surface height H _w and mask lower surface height H _m Since it did in this way, the gap distribution of the arbitrary positions when the board | substrate W and the mask M are made to oppose can be calculated | required easily.

Further, the height H _w and the height H _m of the mask lower surface of the top substrate surface other than the height measurement position, and so as to obtain a linear interpolation from the measured values of the height H _m of height Hw and the mask lower surface of the substrate top surface Therefore, the gap distribution can be obtained at an arbitrary position.

  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 step-type proximity exposure apparatus has been described. However, the present invention is not limited to this, and can be similarly applied to various types of exposure apparatuses that expose and transfer a mask pattern onto a substrate.

DESCRIPTION OF SYMBOLS 1 Mask stage 2 Work stage 3 Irradiation means 5 X-axis stage feed mechanism (work stage drive mechanism)
6 Y-axis stage feed mechanism (work stage drive mechanism)
7 Vertical coarse motion device (work stage drive mechanism)
8 Vertical fine movement device (work stage drive mechanism)
15 Substrate side displacement sensor 31 Mask side displacement sensor (gap sensor)
40 Control device (gap calculation means)
G Gap H _m Height of the lower surface of the mask H _W Height of the upper surface of the substrate M Mask PE Stepwise proximity exposure device (exposure device)
W substrate (material to be exposed)
WE exposure area

Claims (6)

A work stage that can move while holding a substrate as a material to be exposed, a mask stage that is disposed opposite to the substrate and can hold a mask, and irradiates the substrate with light for pattern exposure via the mask. Irradiating means, a work stage driving mechanism for moving the work stage in a predetermined direction, and a mask position adjusting means for adjusting the position of the mask with respect to the substrate, wherein the mask and the substrate are arranged close to each other. A proximity exposure apparatus that exposes and transfers the exposure pattern of the mask to the substrate by the irradiation means,
A mask side displacement sensor provided on the mask stage side for measuring the height of the upper surface of the substrate;
A substrate side displacement sensor provided on the work stage side for measuring the height of the lower surface of the mask;
Based on the height at a plurality of predetermined positions of the upper surface of the substrate measured by the mask side displacement sensor and the height at a plurality of predetermined positions of the lower surface of the mask measured by the substrate side displacement sensor, Gap calculating means for calculating a gap at an arbitrary position when the mask and the mask are opposed to each other;
A proximity exposure apparatus comprising:   The proximity exposure apparatus according to claim 1, wherein the mask side displacement sensor is a non-contact sensor.   2. The proximity according to claim 1, wherein the gap calculating unit calculates the gap for each of a plurality of exposure areas on the substrate in each shot irradiated with light for pattern exposure by the irradiation unit. Exposure device. A work stage that can move while holding a substrate as a material to be exposed, a mask stage that is disposed opposite to the substrate and can hold a mask, and irradiates the substrate with light for pattern exposure via the mask. Irradiating means, a work stage driving mechanism for moving the work stage in a predetermined direction, a mask position adjusting means for adjusting the position of the mask with respect to the substrate, and a height of the upper surface of the substrate provided on the mask stage side A mask side displacement sensor for measuring the mask, and a substrate side displacement sensor provided on the work stage side for measuring the height of the lower surface of the mask, and exposing and transferring the exposure pattern of the mask onto the substrate by the irradiation means. A gap measurement method for measuring a gap distribution between the substrate and the mask of a proximity exposure apparatus,
Moving the work stage by the work stage drive mechanism, and measuring the height of a plurality of predetermined positions on the upper surface of the substrate by the mask side displacement sensor;
Moving the work stage by the work stage drive mechanism and measuring the height of a plurality of predetermined positions on the lower surface of the mask by the substrate side displacement sensor;
Based on the height at a plurality of predetermined positions of the upper surface of the substrate measured by the mask side displacement sensor and the height at a plurality of predetermined positions of the lower surface of the mask measured by the substrate side displacement sensor, And a step of calculating a gap at an arbitrary position when the mask faces each other. A gap measuring method for a proximity exposure apparatus, comprising:   The gap calculating step includes linearly interpolating the height of the upper surface of the substrate other than the height measurement position from the measured values of the height of the upper surface of the substrate at a plurality of predetermined positions and the height of the lower surface of the mask at a plurality of predetermined positions. The gap measuring method for a proximity exposure apparatus according to claim 4, further comprising an interpolation processing step for obtaining a height and a height of the lower surface of the mask.   5. The proximity according to claim 4, wherein the gap calculating step calculates the gap for each of a plurality of exposure areas on the substrate in each shot irradiated with light for pattern exposure by the irradiation unit. A method for measuring a gap of an exposure apparatus.

Images