JP2012073453A - Exposure device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exposure device able to expose a substrate with high accuracy even in divided simultaneous exposure by controlling the flow rate of a cooling water so that a heating medium at the channel exit of a work chuck has a predetermined temperature and by making the temperature of each part of the work chuck uniform.SOLUTION: The exposure device includes: a plurality of heating medium channels 21, 22, and 23 provided in a work chuck 20 with a pressure accumulator 80 connected thereto, and connected parallel to one another to allow passage of a heating medium W; temperature sensors 31, 32, and 33 provided at the exits of the heating medium channels of them and configured to measure the exit temperatures Two1, Two2, and Two3 of the heating medium W; and flow rate adjustment mechanisms 41, 42, and 43 provided for the corresponding heating medium channels 21, 22, and 23 and configured to control the flow rates Gw1, Gw2, and Gw3 of the heating medium W passing through these heating medium channels. Based on each of the exit temperatures of the heating medium W measured by these temperature sensors, the flow rate adjustment mechanism controls the flow rate of the heating medium W and adjusts the temperature of the work chuck 20 to a predetermined temperature.

Description

The present invention relates to an exposure apparatus, and more particularly to an exposure apparatus used when manufacturing a large flat panel display such as a liquid crystal display panel or a plasma display.

The exposure apparatus irradiates the substrate with the parallel light emitted from a light source such as a high-pressure mercury lamp onto a substrate as an exposed material held on the work chuck through a mask on which a mask pattern is drawn. However, since the substrate and the work chuck expand and contract due to heat from the light source, dimensional accuracy and pattern pitch accuracy may be impaired. In order to cope with this problem, cooling water as a heat medium is passed through the work chuck to suppress the temperature rise of the substrate, thereby improving dimensional accuracy and pattern pitch accuracy.

However, since the area of the work chuck has increased with the recent increase in substrate size, there is a possibility that the temperature in the work chuck surface will vary greatly, which is a problem in realizing high-precision exposure. It has become. Conventionally, in order to suppress the temperature variation in the work chuck surface, the cooling water paths are multi-systemed to shorten the path length per system, and the temperature of the injection section and outlet of each path is reduced. Reduce the difference in temperature distribution by reducing the difference, or always place the injection side and outlet side of the path adjacent to each other, canceling the low temperature on the injection side and the high temperature on the outlet side, and averaging the temperature There is known an exposure method that is adapted (see, for example, Patent Document 1).

JP 2000-98618 A

However, in the exposure method described in Patent Document 1, for example, as shown in FIG. 9, four cooling water paths 111, 4 are provided in four areas 101, 102, 103, 104 divided by broken lines of the work chuck 100. 112, 113, and 114, the heat balance model in each region 101, 102, 103, and 104 of the work chuck 100 has a heat quantity of Qn, a cooling water flow rate of Gwn, an inlet cooling water temperature of Twin, and an outlet. When the temperature of the cooling water is Twon and the proportionality constant is Cp, the following equation (Equation 1) is obtained. The suffix “n” indicates the number of each area.

The temperature Twon of the cooling water at the outlet is expressed as the following equation (Equation 2) by modifying the above equation (Equation 1).

When the substrates held on the work chuck 100 are collectively exposed, exposure light is uniformly irradiated on the entire surface of the work chuck 100, that is, the regions 101, 102, 103, and 104 are uniformly heated. Therefore, Q1 = Q2 = Q3 = Q4 = Q, and the temperature of the cooling water at the outlet Twon is expressed by the following equation (Equation 3). That is, if the cooling water inlet temperature Twin and the flow rate Qn are the same (usually the same because the apparatus can be simplified), the cooling water outlet temperature Twon is set to each of the regions 101, 102, 103, 104 is the same, there is little variation in temperature within the work chuck surface, and there is almost no effect on the dimensional accuracy and pattern pitch accuracy.

On the other hand, when the substrate held by the work chuck 100, which is becoming mainstream in recent years with the increase in the size of the substrate, is divided and sequentially exposed, Q1 = QW1, Q2 = Q3 = Q4 = Since it is 0, the outlet temperature Twon of the cooling water is different between the region 101 and the regions 102, 103, and 104 as shown by the following equation (Equation 4), and the temperature distribution of the work chuck 100 collapses.

Similarly, when the area 2 is exposed, since Q2 = QW2 and Q1 = Q3 = Q4 = 0, the outlet temperature Twon of the cooling water is equal to the area 102 as expressed by the following equation (Equation 5). Unlike the areas 101, 103, and 104, the temperature distribution of the work chuck 100 collapses.

Further, when the area 3 is exposed, since Q3 = QW3 and Q1 = Q2 = Q4 = 0, the outlet temperature Twon of the cooling water is expressed by the area 103 as expressed by the following equation (Equation 6): Unlike the regions 101, 102, and 104, the temperature distribution of the work chuck 100 collapses.

Further, when the region 4 is exposed, since Q4 = QW4 and Q1 = Q2 = Q3 = 0, the outlet temperature Twon of the cooling water is expressed by the region 104 as expressed by the following equation (Equation 7). Unlike the regions 101, 102, and 103, the temperature distribution of the work chuck 100 collapses.

As described above, in the division sequential exposure, there is a possibility that the temperature distribution of the work chuck 100 varies and the substrate expands / contracts due to the thermal deformation of the work chuck 100, thereby reducing the dimensional accuracy and the pattern pitch accuracy. It was. In addition, when switching the exposure position between the first, second, third, and fourth sheets, unsteady radiant heat flows into the work chuck 100, which further complicates the temperature distribution and adversely affects dimensional accuracy. Could give.

Further, as shown in FIG. 10, the flow rate Gwn of the cooling water flowing through the cooling water paths 111, 112, 113, 114 is expressed by the pump characteristic curve PQ and the pressure loss curve RCn (for each cooling water path 111, 112, 113, 114). RC1, RC2, RC3, RC4) and intersection points P1, P2, P3, P4. The pressure loss curve RCn may be different for each route depending on the piping configuration, the occurrence of rust in the piping, the change over time such as scale adhesion, and the like. Thus, if the flow rate Gwn is different for each of the cooling water paths 111, 112, 113, 114, the temperature distribution of the work chuck 100 may vary, and the dimensional accuracy and pattern pitch accuracy may decrease.

Furthermore, if some of the cooling water paths 111, 112, 113, 114 are closed for some reason, the cooling water concentrates on the remaining cooling water paths, and the flow velocity in the cooling water path increases. Along with this, vibration due to the flow of fluid increases, and the exposure accuracy of the apparatus may deteriorate.

The present invention has been made to eliminate such inconveniences, and its purpose is to control the flow rate of the cooling water so that the temperature of the cooling water (heat medium) at the exit of the work chuck passage becomes a predetermined temperature. An object of the present invention is to provide an exposure apparatus capable of controlling and uniformizing the temperature of each part of the work chuck and exposing a substrate with high dimensional accuracy even in divided sequential exposure.

The above object of the present invention can be achieved by the following constitution.
(1) An exposure apparatus that divides and sequentially exposes a mask pattern on a substrate as an exposed material held by a work chuck, and is provided on a work chuck connected to a pressure accumulator that keeps the pressure of a heat medium constant, and is parallel to each other. A plurality of heat medium passages that are connected and allow the heat medium to pass through, a temperature sensor that is provided on each outlet side of the plurality of heat medium passages, and that measures the outlet temperature of the heat medium, and a plurality of heat medium passages, respectively And a flow rate adjusting mechanism for controlling the flow rate of the heat medium passing through the heat medium flow path, and the flow rate adjusting mechanism controls the flow rate of the heat medium based on the outlet temperature of the heat medium measured by the temperature sensor. And an exposure apparatus for adjusting the temperature of the work chuck to a predetermined temperature.
(2) The exposure apparatus according to (1), wherein the flow rate adjusting mechanism is connected in series to the heat medium flow path.
(3) The exposure apparatus according to (1), wherein the flow rate adjusting mechanism is connected in parallel to the heat medium flow path.
(4) The heat medium flow path further includes a flow sensor for measuring the flow rate of the heat medium flowing through each heat medium flow path, and when the measured value of the flow sensor exceeds a predetermined flow rate or less than the predetermined flow rate When it becomes, the exposure apparatus according to any one of (1) to (3), wherein an abnormality is determined and a warning is issued or the apparatus is stopped.

According to the exposure apparatus of the present invention, the work chuck is provided with a plurality of heat medium flow paths for allowing the heat medium to pass therethrough in parallel with each other, and the heat supplied from the supply pump before the heat medium passes through the work chuck. A pressure accumulator that makes the pressure of the medium constant, a temperature sensor that measures the outlet temperature of the heat medium in each heat medium flow path, and a flow rate adjustment mechanism that controls the flow rate of the heat medium passing through each heat medium flow path. Since the flow rate adjusting mechanism controls the flow rate of the heating medium so that the outlet temperature of the heating medium becomes the same based on the outlet temperature of the heating medium that is provided and measured by the temperature sensor, the temperature distribution of the work chuck is predetermined. Since the temperature is uniformly controlled, the expansion and contraction due to the heat of the work chuck and the substrate can be made uniform. As a result, the substrate can be exposed with high dimensional accuracy in batch exposure as well as batch exposure.

In addition, according to the exposure apparatus of the present invention, each heat medium flow path is provided with a flow rate adjusting mechanism and adjusts the flow rate of the heat medium for each heat medium flow path, so that it is designed like a conventional heat medium flow path. Sometimes it is not necessary to strictly consider the piping balance so that the flow rates of the respective heat medium passages are the same, and the restriction on the piping layout is reduced, and the degree of freedom in design can be greatly improved. Thereby, the cost of the piping member can be reduced, and the manufacturing cost of the exposure apparatus can be reduced.

Further, according to the exposure apparatus of the present invention, the flow rate adjusting mechanism is connected in series to the heat medium flow path, so that the flow rate of the heat medium flowing through each heat medium flow path can be adjusted independently and accurately. And the temperature distribution of the work chuck can be controlled to be uniform. Thereby, high-precision exposure can be performed while suppressing the influence of heat on the exposure accuracy.

Further, according to the exposure apparatus of the present invention, since the flow rate adjusting mechanism is connected in parallel to the heat medium flow path, the flow rate of the heat medium flowing through each heat medium flow path can be adjusted independently and accurately. The temperature distribution of the work chuck can be controlled to be uniform. Thereby, high-precision exposure can be performed while suppressing the influence of heat on the exposure accuracy.

Furthermore, according to the exposure apparatus of the present invention, the heat medium flow path further includes a flow sensor for measuring the flow rate of the heat medium flowing through each heat medium flow path, and the measured value of the flow sensor exceeds a predetermined flow rate. Or when the flow rate is less than the predetermined flow rate, it is judged as abnormal and a warning is issued or the device is stopped. Therefore, the production loss is prevented by preventing the occurrence of defective products due to the temperature distribution variation of the work chuck. be able to.

It is a schematic block diagram for demonstrating 1st Embodiment of the exposure apparatus which concerns on this invention. FIG. 2 is a layout diagram of three heat medium flow paths disposed in the work chuck illustrated in FIG. 1. It is a flowchart which shows the procedure which adjusts a flow volume based on the exit temperature of the heat carrier of 1st Embodiment. It is a flowchart which shows the control procedure in the case of the excess flow volume abnormality of the heat medium of 1st Embodiment. It is a flowchart which shows the control procedure in the case of the flow volume fall abnormality of a heat medium. It is a schematic block diagram for demonstrating 2nd Embodiment of the exposure apparatus which concerns on this invention. It is a flowchart which shows the procedure which adjusts a flow volume based on the exit temperature of the heat carrier of 2nd Embodiment. It is a flowchart which shows the control procedure in the case of the flow volume excess abnormality of the heat medium of 2nd Embodiment. It is the schematic for demonstrating the work chuck | zipper of the conventional exposure apparatus.

Hereinafter, embodiments of an exposure apparatus according to the present invention will be described in detail with reference to the drawings.

First, a first embodiment of an exposure apparatus according to the present invention will be described with reference to FIGS.
FIG. 1 is a schematic block diagram for explaining a first embodiment of an exposure apparatus according to the present invention, FIG. 2 is a layout diagram of three heat medium flow paths arranged in the work chuck shown in FIG. 1, and FIG. The flowchart which shows the procedure which adjusts a flow volume based on the exit temperature of the heat carrier of 1st Embodiment, FIG. 4 is a flowchart which shows the control procedure in the case of excess flow volume abnormality of the heat medium of 1st Embodiment, FIG. It is a flowchart which shows the control procedure in the case of abnormal flow volume fall.

The exposure apparatus 11 according to the present embodiment performs exposure by sequentially dividing a mask pattern onto a substrate (not shown) as a material to be exposed. As shown in FIG. 1, a work chuck 20 that holds the substrate, a work chuck, and the like. 20, three heat medium flow paths 21, 22, and 23 connected in parallel to each other, temperature sensors 31, 32, and 33 respectively disposed in the heat medium flow paths 21, 22, and 23, and flow rate adjustment The mechanisms 41, 42, 43 and the flow rate sensors 51, 52, 53 and the upstream side of the heat medium flow paths 21, 22, 23 are integrated into one and connected to the pressure accumulator 80, via the supply pump 60, The supply pipe 62 connected to the cooling water tank 61 in which the cooling water W is stored and the outlet side (downstream side) of the heat medium passages 21, 22, 23 are integrated into one and connected to the cooling water tank 61. And a return pipe 63.

Further, as shown in FIG. 2, the heat medium flow paths 21, 22, and 23 are disposed independently of each other in the three regions 20 </ b> A, 20 </ b> B, and 20 </ b> C of the work chuck 20 that are partitioned by phantom lines. The cooling water W, which is a heat medium, is supplied from one end of the flow paths 21, 22, and 23 and flows out from the other end. Moreover, the heat medium flow paths 21, 22, and 23 are disposed over the entire areas 20A, 20B, and 20C, and are configured so that the temperatures of the areas 20A, 20B, and 20C are uniform.

The temperature sensors 31, 32, 33 are connected in series to the downstream sides of the heat medium flow paths 21, 22, 23, respectively, are composed of thermistors and the like, and are cooled through the heat medium flow paths 21, 22, 23. The outlet temperature Twon (Two1, Two2, Two3) of the water W is measured.

The flow rate adjusting mechanisms 41, 42, 43 are connected in series to the downstream sides of the heat medium flow paths 21, 22, 23, respectively, and open and close a built-in unillustrated valve mechanism to open each heat medium flow path 21, The flow rate Gwn (Gw1, Gw2, Gw3) of the cooling water W flowing through 22 and 23 is adjusted.

The flow rate sensors 51, 52, 53 are connected in series to the upstream side of the heat medium flow paths 21, 22, 23, respectively, and the flow rate Gwn of the cooling water W flowing through the heat medium flow paths 21, 22, 23 ( Gw1, Gw2, Gw3) are measured.

Further, the temperature sensors 31, 32, 33, the flow rate adjusting mechanisms 41, 42, 43, and the flow rate sensors 51, 52, 53 are electrically connected to a control device (not shown), and the temperature sensors 31, 32, 33, In addition, measurement results from the flow sensors 51, 52, and 53 are input to the control device, and operation commands to the flow adjustment mechanisms 41, 42, and 43 are output. That is, the control device operates the flow rate adjusting mechanisms 41, 42, 43 based on the outlet temperature Twon of the cooling water W measured by the temperature sensors 31, 32, 33, and appropriately adjusts the flow rate Gwn of the cooling water W. Further, the exposure apparatus 11 is controlled by determining whether or not the exposure apparatus 11 is abnormal based on the flow rate of the cooling water W measured by the flow sensors 51, 52, and 53.

In the exposure apparatus 11 configured as described above, the cooling water W stored in the cooling water tank 61 is sucked up by the supply pump 60, and the pressure of the cooling water W is adjusted by the pressure accumulator 80 via the supply pipe 62. It is made constant and flows into the heat medium flow paths 21, 22, and 23. Then, the flow rate Gwn of the cooling water W in each heat medium flow path 21, 22, 23 is measured by the flow rate sensors 51, 52, 53, and after passing through the work chuck 20, each heat medium flow path 21, 22, 23. The cooling water W whose outlet temperature Twon is measured by the temperature sensors 31, 32, 33 and whose flow rate Gwn is adjusted by the flow rate adjusting mechanisms 41, 42, 43 is integrated into one return pipe 63. And returned to the cooling water tank 61.

Next, the control procedure of the exposure apparatus 11 of this embodiment will be described with reference to FIGS.
As shown in FIG. 3, the outlet temperature of the cooling water W is controlled by first setting the water temperature upper limit value Tmax and the water temperature lower limit value Tmin of the outlet temperature Twon of the cooling water W (S <b> 1-1). After a predetermined time has elapsed from the start (S1-2), the outlet temperatures Two1, Two2, Two3 of the cooling water W of the heat medium passages 21, 22, 23 measured by the temperature sensors 31, 32, 33 and the water temperature upper limit value Tmax Are compared (S1-3).

When any of the outlet temperatures Two1, Two2, and Two3 exceeds the water temperature upper limit value Tmax, the flow rate adjusting mechanisms 41, 42, and 43 of the corresponding heat medium passages 21, 22, and 23 are operated to operate the valves. The opening degree is opened, and the cooling power of the corresponding part of the work chuck 20 is increased by increasing the flow rate of the cooling water W in the corresponding heat medium passages 21, 22, 23 (S1-4). Then, it is checked whether or not the exposure apparatus 11 is stopped (S1-7).

Further, in the above (S1-3), when the outlet temperatures Two1, Two2, Two3 do not exceed the water temperature upper limit value Tmax, the outlet temperatures Two1, Two2, Two3 and the water temperature lower limit value Tmin are compared (S1-5). ). If any of the outlet temperatures Two1, Two2, and Two3 is less than the water temperature lower limit value Tmin, the flow rate adjusting mechanisms 41, 42, and 43 of the corresponding heat medium passages 21, 22, and 23 are operated. The valve opening is closed and the cooling power of the corresponding part of the work chuck 20 is suppressed by reducing the flow rate of the cooling water W in the corresponding heat medium passages 21, 22, 23 (S1-6). Then, it is checked whether or not the exposure apparatus 11 is stopped (S1-7).

Further, when the outlet temperatures Two1, Two2, Two3 do not exceed the water temperature upper limit value Tmax and do not become less than the water temperature lower limit value Tmin (in the case of (S1-5) No), the outlet temperature Two1, Since Two2 and Two3 are within an appropriate temperature range, it is checked whether or not the exposure apparatus 11 is stopped without operating the flow rate adjusting mechanisms 41, 42, and 43 (S1-7). If the exposure apparatus 11 is stopped, the process returns to the main routine. If the exposure apparatus 11 is in operation, the process returns to before (S1-2) and the same control is performed again after a predetermined time has elapsed.

As described above, the outlet temperatures Two1, Two2, Two3 are compared for each of the heat medium flow paths 21, 22, 23 with the water temperature upper limit value Tmax and the water temperature lower limit value Tmin, and the heat medium flow paths 21, The flow rate adjusting mechanisms 41, 42, 43 of 22 and 23 are individually operated to adjust the flow rate of the cooling water W. That is, when the water temperature upper limit value Tmax is exceeded, the flow rate of the cooling water W is increased, and when it is less than the water temperature lower limit value Tmin, the flow rate of the cooling water W is decreased. Thereby, the cooling power of the high temperature portion of the work chuck 20 is increased, the cooling power of the low temperature portion is suppressed, and the entire surface of the work chuck 20 is controlled to be within a predetermined temperature range. As a result, a reduction in exposure accuracy of the substrate due to the temperature distribution of the work chuck 20 is prevented.

Next, with reference to FIG. 4, the abnormality detection in the case where the flow rate of the cooling water W in the heat medium passages 21, 22, 23 abnormally increases and the flow rate of the cooling water W increases will be described.
First, a flow rate upper limit Gmax of the flow rate Gwn of the cooling water W is set (S2-1), and after a predetermined time has elapsed from the start of operation of the exposure apparatus 11 (S2-2), it is measured by the flow rate sensors 51, 52, and 53. The flow rates Gw1, Gw2, and Gw3 of the heat medium flow paths 21, 22, and 23 are compared with the flow rate upper limit Gmax (S2-3). If any of the flow rates Gw1, Gw2, Gw3 exceeds the flow rate upper limit Gmax, the flow rate adjusting mechanisms 41, 42, 43 of the corresponding heat medium flow paths 21, 22, 23 are operated to open the valves. The degree is closed and the flow rate of the cooling water W in the corresponding heat medium passages 21, 22, 23 is decreased (S2-4). Then, it is checked whether or not the exposure apparatus 11 is stopped (S2-5).

In the above (S2-3), when the flow rates Gw1, Gw2, and Gw3 do not exceed the flow rate upper limit Gmax, the same control is performed after a predetermined time again after returning to (S2-2). If the exposure apparatus 11 is stopped, the process returns to the main routine. If the exposure apparatus 11 is in operation, the process returns to before (S2-2) and the same control is performed again after a predetermined time has elapsed. As a result, vibrations that occur when the flow rate of the cooling water W is higher than expected are prevented, and a reduction in exposure accuracy is prevented.

Next, referring to FIG. 5, an abnormality occurs when the flow rate of the cooling water W excessively decreases due to clogging of the heat medium passages 21, 22, 23, a failure of the flow rate adjustment mechanisms 41, 42, 43, or the like. The detection will be described.
First, the lower limit value Gmin of the flow rate Gwn of the cooling water W is set (S3-1), and after a predetermined time has elapsed from the start of operation of the exposure apparatus 11 (S3-2), the flow rate is measured by the flow rate sensors 51, 52, and 53. The flow rates Gw1, Gw2, and Gw3 of the heat medium flow paths 21, 22, and 23 are compared with the flow rate lower limit Gmin (S3-3). If any one of the flow rates Gw1, Gw2, and Gw3 is less than the flow rate lower limit Gmin, it is determined that an apparatus abnormality has occurred and the operation of the exposure apparatus 11 is stopped (S3-4). Then, the stop of the exposure apparatus 11 is checked (S3-5).

In the above (S3-3), when the flow rates Gw1, Gw2, and Gw3 are not less than the flow rate lower limit Gmin, the same control is performed after a predetermined time again after returning to (S3-2). If the exposure apparatus 11 is stopped, the process returns to the main routine. If the exposure apparatus 11 is not stopped, the process returns to (S3-2) and the same control is performed again after a predetermined time has elapsed. As a result, overheating of the work chuck 20 caused by excessively decreasing the flow rate of the cooling water W is prevented, and deterioration in exposure accuracy is prevented. In the above (S3-4), a warning may be issued instead of stopping the apparatus.

As described above, according to the exposure apparatus 11 of the present embodiment, the plurality of heat medium flow paths 21, 22, and 23 that allow the cooling water W to pass through the work chuck 20 connected to the pressure accumulator 80 are connected in parallel to each other. The temperature sensors 31, 32, and 33 that measure the outlet temperatures Two1, Two2, and Two3 of the cooling water W are passed through the heat medium passages 21, 22, and 23, and the heat medium passages 21, 22, and 23, respectively. Flow rate adjusting mechanisms 41, 42, and 43 for controlling the flow rates Gw1, Gw2, and Gw3 of the cooling water W are provided, respectively, and the outlet temperatures Two1, Two2, and Two3 of the cooling water W measured by the temperature sensors 31, 32, and 33 Based on the flow rate adjustment mechanisms 41, 42, 43, the flow rates Gw1, Gw2, Gw3 of the cooling water W are set so that the outlet temperatures Two1, Two2, Two3 of the cooling water W are the same. Gosuru Therefore, the temperature distribution of the workpiece chuck 20 is uniformly controlled at a predetermined temperature, it is possible to equalize the stretch by the work chuck 20 and the substrate of the heat. As a result, the substrate can be exposed with high dimensional accuracy in batch exposure as well as batch exposure.

Further, according to the exposure apparatus 11 of the present embodiment, each of the heat medium flow paths 21, 22, 23 includes the flow rate adjusting mechanisms 41, 42, 43, and the cooling water is provided for each heat medium flow path 21, 22, 23. Since the flow rates Gw1, Gw2, and Gw3 of W are adjusted, it is not necessary to consider that the flow rate of each heat medium flow path is the same in consideration of the piping balance at the time of design like the conventional heat medium flow path. As a result, restrictions on the piping layout are reduced, and the degree of freedom in design can be greatly improved. Thereby, the cost of the piping member can be reduced, and the manufacturing cost of the exposure apparatus 11 can be reduced.

Furthermore, according to the exposure apparatus 11 of the present embodiment, the heat medium flow paths 21, 22, and 23 measure the flow rates Gw1, Gw2, and Gw3 of the cooling water W that flow through the heat medium flow paths 21, 22, and 23, respectively. Flow rate sensors 51, 52, and 53 are further provided. When the measured values of the flow rate sensors 51, 52, and 53 exceed a predetermined flow rate Gmax or less than a predetermined flow rate Gmin, an abnormality is determined and a warning is issued. Alternatively, since the apparatus 10 is stopped, the production loss can be prevented by preventing the generation of defective products due to the variation in the temperature distribution of the work chuck 20.

(Second Embodiment)
Next, a second embodiment of the exposure apparatus according to the present invention will be described with reference to FIGS. Note that portions that are the same as or equivalent to those of the first embodiment are denoted by the same reference numerals in the drawings, and description thereof is omitted or simplified.
6 is a schematic block diagram for explaining a second embodiment of the exposure apparatus according to the present invention, FIG. 7 is a flowchart showing a procedure for adjusting the flow rate based on the outlet temperature of the heat medium according to the second embodiment, and FIG. These are the flowcharts which show the control procedure in the case of the flow volume excess abnormality of 2nd Embodiment.

As shown in FIG. 6, the exposure apparatus 12 of the present embodiment includes a work chuck 20 that holds a substrate, and three heat medium channels 21, 22, and 23 that are disposed on the work chuck 20 and connected in parallel to each other. And bypass flow paths 71, 72, 73 connected in parallel to the heat medium flow paths 21, 22, 23, and flow rate adjusting mechanisms 41, 42, 43 respectively disposed in the bypass flow paths 71, 72, 73, The temperature sensors 31, 32, and 33 and the flow rate sensors 51, 52, and 53 disposed in the heat medium flow paths 21, 22, and 23, respectively, and the upstream side of the heat medium flow paths 21, 22, and 23 are integrated into one. The supply pipe 62 connected to the accumulator 80 and connected to the cooling water tank 61 in which the cooling water W is stored via the supply pump 60, and the outlet side (downstream side) of the heat medium passages 21, 22, and 23 ) Is integrated into one and the cooling water tank 61 It comprises a return pipe 63 connected.

Next, the control procedure of the exposure apparatus 12 of this embodiment will be described with reference to FIGS.
As shown in FIG. 7, the control of the outlet temperature of the cooling water W is performed by first setting the water temperature upper limit value Tmax and the water temperature lower limit value Tmin of the outlet temperature Twon of the cooling water W (S4-1) and operating the exposure apparatus 12. After the elapse of a predetermined time from the start (S4-2), the outlet temperatures Two1, Two2, Two3 of the cooling water W of the heat medium flow paths 21, 22, 23 measured by the temperature sensors 31, 32, 33 and the water temperature upper limit value Tmax Are compared (S4-3).

When any of the outlet temperatures Two1, Two2, and Two3 exceeds the water temperature upper limit value Tmax, the flow rates of the bypass passages 71, 72, and 73 connected to the corresponding heat medium passages 21, 22, and 23, respectively. The adjustment mechanisms 41, 42 and 43 are operated to close the valve opening, and the flow rate of the cooling water W in the corresponding heat medium passages 21, 22, and 23 is increased to increase the cooling power of the corresponding part of the work chuck 20. (S4-4). Then, it is checked whether or not the exposure apparatus 12 is stopped (S4-7).

Further, in the above (S4-3), when the outlet temperatures Two1, Two2, and Two3 do not exceed the water temperature upper limit value Tmax, the outlet temperatures Two1, Two2, and Two3 are compared with the water temperature lower limit value Tmin (S4-5). ). When any of the outlet temperatures Two1, Two2, and Two3 is less than the water temperature lower limit value Tmin, the bypass channels 71, 72, and 73 connected to the corresponding heat medium channels 21, 22, and 23 The flow rate adjusting mechanisms 41, 42, 43 are operated to open the valve opening, and the flow rate of the cooling water W in the corresponding heat medium passages 21, 22, 23 is decreased to suppress the cooling power of the corresponding part of the work chuck 20. (S4-6). Then, it is checked whether or not the exposure apparatus 12 is stopped (S4-7).

Further, when the outlet temperatures Two1, Two2, Two3 do not exceed the water temperature upper limit value Tmax and are not less than the water temperature lower limit value Tmin (in the case of (S4-5) No), the outlet temperature Two1, Since Two2 and Two3 are within an appropriate temperature range, it is checked whether the exposure apparatus 12 is stopped without operating the flow rate adjusting mechanisms 41, 42, 43 (S4-7). If the exposure apparatus 12 is stopped, the process returns to the main routine. If the exposure apparatus 12 is in operation, the process returns to before (S4-2) and the same control is performed again after a predetermined time has elapsed.

As described above, the outlet temperatures Two1, Two2, Two3 are compared for each of the heat medium flow paths 21, 22, 23 with the water temperature upper limit value Tmax and the water temperature lower limit value Tmin, and the heat medium flow paths 21, The flow rate adjusting mechanisms 41, 42, and 43 of the bypass flow paths 71, 72, and 73 connected to 22 and 23 are individually operated to adjust the flow rate of the cooling water W. That is, when the water temperature upper limit value Tmax is exceeded, the flow rate of the cooling water W is increased, and when it is less than the water temperature lower limit value Tmin, the flow rate of the cooling water W is decreased. Thereby, the cooling power of the high temperature portion of the work chuck 20 is increased, the cooling power of the low temperature portion is suppressed, and the entire surface of the work chuck 20 is controlled to be within a predetermined temperature range. As a result, a reduction in exposure accuracy of the substrate due to the temperature distribution of the work chuck 20 is prevented.

Next, with reference to FIG. 8, the abnormality detection in the case where the flow rate of the cooling water W in the heat medium passages 21, 22, 23 abnormally increases and the flow rate of the cooling water W increases will be described.
First, a flow rate upper limit Gmax of the flow rate Gwn of the cooling water W is set (S5-1), and measured by the flow rate sensors 51, 52, and 53 after a predetermined time has elapsed from the start of operation of the exposure apparatus 12 (S5-2). The flow rates Gw1, Gw2, Gw3 of the heat medium flow paths 21, 22, 23 and the flow rate upper limit Gmax are compared (S5-3). When any one of the flow rates Gw1, Gw2, Gw3 exceeds the flow rate upper limit Gmax, the flow rate adjustment of the bypass flow channels 71, 72, 73 connected to the corresponding heat medium flow channels 21, 22, 23 is performed. The mechanisms 41, 42, and 43 are operated to open the valve opening, and the flow rate of the cooling water W in the corresponding heat medium passages 21, 22, and 23 is decreased (S5-4). Then, it is checked whether or not the exposure apparatus 12 is stopped (S5-5).

In (S5-3), when the flow rates Gw1, Gw2, and Gw3 do not exceed the flow rate upper limit Gmax, the same control is performed again after the elapse of a predetermined time after returning to (S5-2). If the exposure apparatus 12 is stopped, the process returns to the main routine. If the exposure apparatus 12 is in operation, the process returns to before (S5-2) and the same control is performed again after a predetermined time has elapsed. As a result, vibrations that occur when the flow rate of the cooling water W is higher than expected are prevented, and a reduction in exposure accuracy is prevented.

In addition, about abnormality detection when the flow volume of the cooling water W of the heat medium flow paths 21, 22, and 23 decreases excessively, since it is the same as that of 1st Embodiment, description is abbreviate | omitted.

As described above, according to the exposure apparatus 12 of the present embodiment, the plurality of heat medium flow paths 21, 22, and 23 that allow the cooling water W to pass through the work chuck 20 connected to the pressure accumulator 80 are connected in parallel to each other. The bypass channels 71, 72, 73 are connected in parallel to the heat medium channels 21, 22, 23, and the outlet temperatures Two 1, Two 2, Two 3 of the cooling water W are supplied to the heat medium channels 21, 22, 23. Temperature sensors 31, 32, 33 to be measured are provided, and flow rate adjustments for controlling the flow rates Gw 1, Gw 2, Gw 3 of the cooling water W passing through the heat medium channels 21, 22, 23 in the bypass channels 71, 72, 73, respectively. Mechanisms 41, 42, and 43 are provided, respectively, and flow rate adjustment mechanisms 41, 42, and, based on the outlet temperatures Two1, Two2, and Two3 of the cooling water W measured by the temperature sensors 31, 32, and 33, respectively. 3 controls the flow rate Gw1, Gw2, Gw3 of the cooling water W so that the outlet temperatures Two1, Two2, Two3 of the cooling water W are the same, so that the temperature distribution of the work chuck 20 is uniformly controlled at a predetermined temperature. Therefore, the expansion and contraction due to the heat of the work chuck 20 and the substrate can be made uniform. As a result, the substrate can be exposed with high dimensional accuracy in batch exposure as well as batch exposure.
About another structure and an effect, it is the same as that of the said 1st Embodiment.

In addition, this invention is not limited to what was illustrated by said each embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.
For example, in each of the above embodiments, the case where the work chuck is provided with the three heat medium flow paths is illustrated, but the heat medium flow path is not limited to the three lines, depending on the size of the work chuck or the like. Any number of heat medium channels can be provided.
Moreover, in each said embodiment, although cooling water is used for a heat medium, if it is the fluid which can pass a heat medium flow path and a bypass flow path, there will be no restriction | limiting in the kind.

DESCRIPTION OF SYMBOLS 11, 12 Exposure apparatus 20 Work chuck 21, 22, 23 Heat medium flow path 31, 32, 33 Temperature sensor 41, 42, 43 Flow rate adjustment mechanism 51, 52, 53 Flow rate sensor 60 Supply pump 61 Cooling water tank 62 Supply pipe 63 Return pipe 71, 72, 73 Bypass flow path 80 Accumulator W Cooling water (heat medium)
Gwn (Gw1, Gw2, Gw3) Heat medium flow rate Twon (Two1, Two2, Two3) Heat medium outlet temperature

Claims (4)

An exposure apparatus that divides and sequentially exposes a mask pattern on a substrate as an exposed material held by a work chuck,
Provided in the work chuck connected to a pressure accumulator that makes the pressure of the heat medium constant,
A plurality of heat medium flow paths that are connected in parallel to each other and pass the heat medium;
A temperature sensor provided on each of the outlet sides of the plurality of heat medium flow paths, and measuring an outlet temperature of the heat medium;
A flow rate adjusting mechanism that is provided in each of the plurality of heat medium flow paths and controls the flow rate of the heat medium that passes through the heat medium flow path,
An exposure apparatus characterized in that, based on the outlet temperature of the heat medium measured by the temperature sensor, the flow rate adjusting mechanism controls the flow rate of the heat medium to adjust the temperature of the work chuck to a predetermined temperature. .   The exposure apparatus according to claim 1, wherein the flow rate adjusting mechanism is connected in series to the heat medium flow path.   The exposure apparatus according to claim 1, wherein the flow rate adjusting mechanism is connected in parallel to the heat medium flow path. The heat medium flow path further includes a flow rate sensor for measuring a flow rate of the heat medium flowing through each of the heat medium flow paths,
When the measured value of the flow rate sensor exceeds a predetermined flow rate or becomes less than a predetermined flow rate, it is judged as abnormal and a warning is issued or the apparatus is stopped. The exposure apparatus according to any one of the above.

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