JP2004080059A - Projection aligner and projection exposure method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection aligner in which the positional accuracy of a pattern on a wafer can be improved by stabilizing the temperature of a reduction projection lens, and a projection exposure method. <P>SOLUTION: The projection aligner has a light source 7 for radiation of light to a reticle 8 and the reduction projection lens 10 to project the light from the light source 7 transmitted through the reticle 8 on the wafer 11. The temperature of the reduction projection lens 10 is adjusted by applying a gaseous body of which the temperature is adjusted within a range of ±0.1°C of the setting temperature. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to a projection exposure apparatus and a projection exposure method for projecting and exposing a pattern drawn on a reticle onto a wafer.

FIG. 25 is a schematic configuration diagram of a conventional projection exposure apparatus 1 housed in an environmental chamber 2. The environmental chamber 2 has a function of managing the surrounding environment of the projection exposure apparatus 1, for example, temperature, dust, and the like.

FIG. 26 is a configuration diagram schematically showing an air conditioning unit provided in the environmental chamber 2. As shown in FIG. 26, the surrounding environment of the projection exposure apparatus 1 is controlled and controlled by an air conditioning unit having a cooler 3, a heater 4, a blower 5, and an ULPA filter (ultra low penetration air-filter) 6. Dust is removed. In FIG. 26, white arrows indicate the flow of clean air in the environmental chamber 2.

FIG. 27 is a perspective view schematically showing a part of the projection exposure apparatus 1 shown in FIGS. 25 and 26. As shown in FIG. 27, the projection exposure apparatus 1 includes a light source 7, a reticle table 9 on which a reticle 8 is mounted, a reduction projection lens 10, a wafer table on which a wafer 11 is mounted, and an XY stage unit 12. At the time of exposure, the pattern drawn on the reticle 8 is projected on the wafer 11 through the reduction projection lens 10 by the light from the light source 7.

By the way, in recent years, three technical changes have been required for the projection exposure apparatus so as to be compatible with the most advanced devices. The first is to use a 4 × reticle instead of the current 5 × reticle as a countermeasure to decrease the exposure throughput due to the increase in the scale of the ULSI. Second, the current reticle (6 inch × 0.25 inch thick) If the reticle size cannot be accommodated, the reticle size must be increased (for example, 9 inches square x 0.5 inches thick). Third, the light source must be set to the current i-line (wavelength: 365 nm) for ultra-miniaturization. Excimer laser (KrF wavelength: 248 nm, ArF wavelength: 193 nm).

However, when the first change is made, the reticle is required to have a pattern position accuracy that is 20% stricter than the current state, and when the second change is made, the reticle is about 70% stricter than the current state. % (Approximately 60% is added by enlarging the size and 20% is added by quadrupling the reticle), and strict pattern position accuracy is required. For this reason, there has been a problem that the influence of the thermal expansion accompanying the temperature rise of the reticle, which has not conventionally been considered a problem, cannot be ignored.

For example, in the conventional case where the temperature of the clean air in the outside of the housing of the projection exposure apparatus 1, that is, the environment chamber 2 is merely adjusted, when the UV light such as the i-ray is repeatedly irradiated, the reticle Rises by about 0.01 to 0.6 ° C. Further, when the glass type of the reticle is quartz (coefficient of thermal expansion: 7.5 × 10 ⁻⁷ / ° C.) and the temperature of the reticle increases by 0.3 ° C., the wafer at the start of exposure and the temperature of 0.3 ° C. In comparison with the wafer in the above, in the case of a 6-inch reticle (effective area is 125 mm square), a pattern position shift of 0.0281 μm on the reticle and 0.007 μm on the wafer (4 × projection exposure apparatus) occurs, In the case of a 9-inch reticle (effective area is assumed to be 200 mm square), a pattern position shift of 0.045 μm on the reticle and 0.011 μm on the wafer (4 × projection exposure apparatus) occurs.

Further, as can be inferred from the transmittance characteristic diagram of FIG. 28, when an ArF (wavelength: 193 nm) excimer laser is adopted by the third change, an i-line (wavelength: 365 nm) or KrF excimer laser ( (Wavelength: 248 nm), the transmittance is reduced by 10% or more. For this reason, when an ArF excimer laser is used, there is a problem that the absorbed light is converted into heat energy, and the temperature rise of the reticle is further accelerated.

Further, since the temperature of the reduction projection lens 10 is also increased by the condensed light, the distribution of distortion of the lens is changed, the accuracy of the exposure position is reduced, and the pattern position in the wafer is shifted. Was.

Therefore, an object of the present invention is to provide a projection exposure apparatus and a projection exposure method capable of stabilizing the temperature of a reticle or a reduction projection lens, thereby improving the pattern position accuracy of a wafer.

The projection exposure apparatus of the present invention has a reticle table on which a reticle is mounted, a light source that irradiates light to the reticle, and a reduction projection lens that projects light from the light source that has passed through the reticle onto a wafer, and A first temperature control means for adjusting the temperature of the reticle by applying a gas whose temperature has been adjusted within a range of ± 0.1 ° C. to the reticle.

Here, the first temperature control means may include a first blower for sending gas toward the reticle, and a first discharger for discharging gas passing around the reticle.

The first blower may have a first blowout nozzle for sending gas toward the light source side surface of the reticle.

(4) The first blower may have a second blow nozzle for sending gas toward the reticle table.

Also, a first cover surrounding the reticle and the reticle table is provided, and the gas from the first temperature control means can flow into the first cover.

The reticle further includes second temperature control means for adjusting the temperature of the reticle. The second temperature control means includes a first passage formed around the reticle table and a set temperature in the first passage. And a first circulating means for flowing the liquid whose temperature has been adjusted within the range of ± 0.1 ° C.

(3) A third temperature control means for adjusting the temperature of the reduction projection lens by applying a gas whose temperature has been adjusted within a range of ± 0.1 ° C. of the set temperature to the reduction projection lens can be provided.

Further, the third temperature control means may include a second blower that sends gas toward the reduction projection lens, and a second discharger that discharges gas that has passed around the reduction projection lens. it can.

Further, a second cover surrounding the reduction projection lens is provided, and the gas from the third temperature control means can flow into the second cover.

In addition, there is provided fourth temperature adjusting means for adjusting the temperature of the reduction projection lens, and the fourth temperature adjustment means includes a second passage formed around the reduction projection lens and a second passage formed in the second passage. And a second circulating means for flowing a liquid whose temperature has been adjusted within the range of ± 0.1 ° C. of the set temperature.

Further, a projection exposure apparatus according to another aspect of the present invention includes a light source for irradiating light to the reticle, and a reduction projection lens for projecting the light from the light source transmitted through the reticle onto a wafer, and sets the temperature to ± 0. A first temperature control means for adjusting the temperature of the reduction projection lens by applying a gas whose temperature has been adjusted within the range of 1 ° C. to the reduction projection lens is provided.

Here, the first temperature control means may have a blower that sends gas toward the reduction projection lens and a discharger that discharges gas that has passed around the reduction projection lens.

Also, a cover surrounding the reduction projection lens is provided, and the gas from the first temperature control means can flow into the cover.

In addition, there is provided second temperature adjusting means for adjusting the temperature of the reduction projection lens, and the second temperature adjustment means includes a passage formed around the reduction projection lens, and ± 0 of a set temperature within the passage. And a circulating means for flowing a liquid whose temperature has been adjusted within the range of 1 ° C.

According to another aspect of the invention, there is provided a projection exposure apparatus comprising: a light source that irradiates a reticle with light; and a reduction projection lens that projects light from the light source transmitted through the reticle onto a wafer. Temperature adjusting means for adjusting the temperature of the path, the temperature adjusting means being temperature-controlled within a range of ± 0.1 ° C. of a set temperature in the path formed around the reduction projection lens and the path. A circulation means for flowing the liquid.

According to the present invention, the reticle inside the projection exposure apparatus is directly exposed to the gas whose temperature has been controlled within ± 0.1 ° C. of the set temperature by the first temperature control means, so that the temperature of the reticle can be stabilized. Can be. For this reason, even when a 4 × reticle is used or when the size of the reticle is increased, an error in pattern position accuracy in the reticle is suppressed, and a ULSI patterned with high alignment accuracy can be obtained. Therefore, there is an effect that the manufacturing yield of ULSI can be greatly improved.

In addition, when the reticle table is cooled by the liquid, the cooling capacity is higher than that by the cooling by the gas, so that the production yield can be further improved.

In addition, when the reduction projection lens is cooled by a gas adjusted to within ± 0.1 ° C. of the set temperature, the temperature of the reduction projection lens increases even if the projection exposure apparatus repeatedly irradiates UV light or deep UV light. Without this, the distortion distribution of this lens does not change. For this reason, it is possible to obtain a ULSI that is patterned with high alignment accuracy, and it is possible to greatly improve the production yield of the ULSI.

In addition, since the reduction projection lens can be cooled with a liquid adjusted within ± 0.1 ° C. of the set temperature, the temperature of the reduction projection lens does not increase even if the projection exposure apparatus repeatedly irradiates UV light or deep UV light. The distortion distribution of this lens does not change. For this reason, it is possible to obtain a ULSI patterned with high alignment accuracy, and it is possible to greatly improve the production yield of the ULSI. Further, when the reticle table is cooled by the liquid, the cooling capacity is higher than in the case of cooling by the gas, so that the production yield can be further improved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Embodiment 1
FIG. 1 is a configuration diagram schematically showing a projection exposure apparatus according to Embodiment 1 of the present invention.

As shown in FIG. 1, in the first embodiment, the interior of the environmental chamber 2, that is, the surrounding environment of the projection exposure apparatus 1 includes a cooler 3, a heater 4, a blower 5, and an ULPA filter 6. The temperature control and the removal of dust are performed by the air conditioning unit having: In FIG. 1, white arrows indicate the flow of clean air in the environmental chamber 2.

As shown in FIG. 1, the projection exposure apparatus 1 according to the first embodiment includes, for example, a light source 7 such as an ArF excimer laser, a reticle table 9 on which a reticle (for example, a 4 × reticle) 8 is mounted, and a reduced projection. It has a lens 10, a wafer table on which a wafer 11 is placed, and an XY stage section 12. At the time of exposure, the pattern drawn on the reticle 8 is projected onto the wafer 11 by the light from the light source 7.

Further, the projection exposure apparatus 1 of the first embodiment adjusts the temperature of the reticle 8 by directly applying the clean air whose temperature has been adjusted within a range of ± 0.1 ° C. of the set temperature to the reticle 8. An adjustment unit (temperature adjustment unit) 20 is provided. The first temperature control unit 20 supplies a clean air supply unit 21 from which temperature has been adjusted and dust has been removed, a blowing unit 22 that sends the clean air to the inside of the housing 1 a of the projection exposure apparatus 1, and passes around the reticle 8. A discharge unit 23 for discharging the cleaned clean air from the housing 1 a of the projection exposure apparatus 1 and returning the clean air to the supply unit 21.

FIG. 2 is a configuration diagram showing the supply unit 21. As shown in FIG. 2, the supply unit 21 includes a cooler 24, a heater 25, a blower 26, and an ULPA filter 27. The supply unit 21 has a temperature sensor 28, a drive circuit 29 for the cooler 24 and the heater 25, and a control circuit 30 for controlling the operation of the cooler 24 and the heater 25 based on the detection values of the temperature sensor 28. The control circuit 30 controls the operation of the cooler 24 and the heater 25 so that the clean air discharged from the supply unit 21 is within ± 0.1 ° C. of the set temperature. Here, the reason for setting the temperature within ± 0.1 ° C. of the set temperature is that, as described above, when the temperature of a 6-inch reticle (effective area is 125 mm □) rises by 0.3 ° C., Although the pattern position is shifted by about 0.0281 μm, this value is 50% of the value (for example, 0.05 μm or 0.06 μm) adopted as the reticle exposure machine accuracy (overlapping tolerance) required for ULSI fabrication. This is because the remaining tolerance is extremely small. In addition, this is because the error range of the set temperature of the temperature control unit currently in practical use. The installation position of the temperature sensor 28 is not limited to the illustrated position, and may be another position such as the vicinity of the reticle 8.

FIG. 3 is a schematic side view showing the vicinity of the reticle in FIG. 1 in an enlarged manner, and FIG. 4 is a schematic plan view of FIG. 3 and 4, arrows indicate the flow of clean air. As shown in FIG. 1, FIG. 3, or FIG. 4, the blower 22 includes a pipe 22a for sending clean air from the supply section 21 to the inside of the housing of the projection exposure apparatus 1, and a manifold 22b connected to the pipe 22a. And a plurality of blow-off nozzles 22c formed at the tip of the manifold 22b and emitting clean air toward the surface (upper surface) of the reticle 8 on the light source 7 side. Reference numeral 13 denotes a pellicle provided on the reticle 8.

(4) The discharge unit 23 has a discharge port 23a provided on the opposite side of the blast nozzle 22c across the reticle 8, and a pipe 23b for returning clean air to the supply unit 21.

At the time of the projection exposure, as shown in FIGS. 3 and 4, clean air adjusted by the first temperature control unit 20 to within ± 0.1 ° C. of the set temperature is blown out of the entire upper surface of the reticle 8 from the blowing nozzle 22c ( That is, the reticle 8 is directly applied to the pellicle surface and the pattern surface) and flows toward the discharge port 23a along the upper surface of the reticle 8.

As described above, according to the projection exposure apparatus 1 of the first embodiment, not only the temperature of the outside of the casing 1a of the projection exposure apparatus 1 is adjusted, but also the inside of the casing 1a of the projection exposure apparatus 1. Since the clean air whose temperature has been adjusted within ± 0.1 ° C. of the set temperature by the first temperature control unit 20 is directly applied to the reticle 8, the temperature of the reticle 8 can be stabilized. For this reason, even when a 4 × reticle is used or when the size of the reticle is increased, an error in the pattern position accuracy in the reticle 8 is suppressed, and a ULSI patterned with high precision alignment accuracy is obtained. Therefore, the manufacturing yield of ULSI can be greatly improved. Further, since there is no pellicle on the upper surface of the reticle 8, in the case of this embodiment in which clean air is blown on the upper surface of the reticle 8, the cooling effect is large.

Embodiment 2
FIG. 5 is a configuration diagram schematically showing a projection exposure apparatus according to the second embodiment of the present invention. FIG. 6 is a schematic side view showing the vicinity of the reticle in FIG. 5 in an enlarged manner, and FIG. 7 is a schematic plan view of FIG.

In FIGS. 5 to 7, the same reference numerals are given to the same or corresponding components as those in FIGS. 1 to 4 described above. The projection exposure apparatus 30 according to the second embodiment is provided with a cover (box) 31 surrounding the outside of the reticle 8 and the reticle table 9, and in addition to the blowing nozzle 22 c, clean air is provided on the side surface and the lower surface of the reticle table 9. The only difference from the projection exposure apparatus 1 according to the first embodiment is that the projection exposure apparatus 1 according to the first embodiment is provided with a blowing nozzle 22d for flowing the air.

At the time of the projection exposure, as shown in FIGS. 6 and 7, clean air adjusted by the first temperature control unit 20 to within ± 0.1 ° C. of the set temperature is blown from the blowing nozzle 22c and the blowing nozzle 22d to the cover 31. And flows along the upper surface of the reticle 8 and the side and lower surfaces of the reticle table 9 toward the discharge port 23a.

As described above, according to the projection exposure apparatus 30 of the second embodiment, the cover 31 is provided, and in addition to the blowout nozzle 22c directed to the upper surface of the reticle 8, the blowout nozzle 22d directed downward is provided. Therefore, not only both surfaces of the reticle 8 but also the temperature of the reticle table 9 can be stabilized. For this reason, even when a 4 × reticle is used or when the size of the reticle is increased, an error in the pattern position accuracy in the reticle 8 is suppressed, and a ULSI patterned with high precision alignment accuracy is obtained. Therefore, the manufacturing yield of ULSI can be greatly improved.

In the second embodiment, the other points are the same as those in the first embodiment.

Embodiment 3
FIG. 8 is a configuration diagram schematically showing a projection exposure apparatus according to Embodiment 3 of the present invention. 9 is an enlarged schematic side view showing the vicinity of the reticle in FIG. 8, and FIG. 10 is a schematic plan view in FIG.

8 to 10, the same reference numerals are given to the same or corresponding components as those in FIGS. 1 to 4. The projection exposure apparatus 40 of the third embodiment differs from the projection exposure apparatus 1 of the first embodiment only in that a second temperature control unit 41 for adjusting the temperature of the reticle 8 is provided. The second temperature control unit 41 has a cooling water supply section 42 and a pipe 43 for flowing the cooling water.

FIG. 11 is a configuration diagram showing the supply unit 41. As shown in FIG. 11, the supply unit 41 includes a cooler 44, a heater 45, and a pump 46. The supply unit 41 has a temperature sensor 47, a drive circuit 48 for the cooler 44 and the heater 45, and a control circuit 49 for controlling the operation of the cooler 44 and the heater 45 based on the detection values of the temperature sensor 47. The control circuit 49 controls the operation of the cooler 44 and the heater 45 so that the cooling water discharged from the supply unit 41 is within ± 0.1 ° C. of the set temperature. The installation position of the temperature sensor 47 is not limited to the illustrated position, but may be another position such as the vicinity of the reticle table 9.

At the time of the projection exposure, as shown in FIGS. 9 and 10, clean air adjusted by the first temperature control unit 20 to within ± 0.1 ° C. of the set temperature is directed from the blowing nozzle 22c toward the upper surface of the reticle 8. And discharged from the discharge port 23a. At the same time, the cooling water adjusted by the second temperature control unit 41 to within ± 0.1 ° C. of the set temperature is supplied to the pipe 43 to cool the reticle table 9.

As described above, according to the projection exposure apparatus 40 of the third embodiment, the upper surface of the reticle 8 is cooled with the clean air adjusted to within ± 0.1 ° C. of the set temperature, and the reticle table 9 is cooled at the set temperature. Since cooling is performed with cooling water adjusted to within ± 0.1 ° C., the lower portion of the reticle 8 (for example, the four corners of the reticle and the area in contact with the reticle table 9) is also cooled by the reticle table 9. Is done. Therefore, even when the projection exposure apparatus 40 repeatedly irradiates the reticle 8 with UV light or deep UV light (excimer laser light), the temperature rise of the reticle 8 is more effectively prevented. For this reason, the occurrence of an error in the pattern position accuracy in the reticle 8 is suppressed, and a ULSI patterned with high alignment accuracy is obtained, so that the manufacturing yield of the ULSI can be significantly improved.

The reticle 8 (with a pellicle) is automatically loaded and unloaded on the reticle table 9, but since the pipe 42 is wound around the side of the reticle table 9, it does not hinder the loading and unloading of the reticle.

に お い て In the third embodiment, the other points are the same as the first embodiment.

Embodiment 4
FIG. 12 is a configuration diagram schematically showing a projection exposure apparatus according to Embodiment 4 of the present invention. 13 is an enlarged schematic side view showing the vicinity of the reticle in FIG. 12, and FIG. 14 is a schematic plan view in FIG.

In FIGS. 12 to 14, the same reference numerals are given to the same or corresponding components as those in FIGS. 8 to 11 described above. The projection exposure apparatus 50 according to the fourth embodiment provides clean air on the lower surface and side surfaces of the reticle table 9 in addition to the point having the cover (box) 31 surrounding the outside of the reticle 8 and the reticle table 9 and the blowing nozzle 22c. The only difference from the projection exposure apparatus 40 of the third embodiment is that a blowout nozzle 22d for flowing is provided.

At the time of the projection exposure, as shown in FIGS. 13 and 14, clean air adjusted by the first temperature control unit 20 to within ± 0.1 ° C. of the set temperature is blown from the blowing nozzle 22c and the blowing nozzle 22d to the cover 31. And flows along the upper surface of the reticle 8 and the lower surface of the reticle table 9 toward the discharge port 23a. At the same time, the cooling water adjusted by the second temperature control unit 41 to within ± 0.1 ° C. of the set temperature is caused to flow through the pipe 42 to cool the reticle table 9.

As described above, according to the projection exposure apparatus 50 of the fourth embodiment, the upper surface and the lower surface of the reticle 8 are cooled with the clean air adjusted within ± 0.1 ° C. of the set temperature, and the reticle table 9 is cooled. Since cooling is performed with cooling water adjusted to within ± 0.1 ° C. of the set temperature, even if the reticle 8 is repeatedly irradiated with UV light or deep UV light, a rise in the temperature of the reticle 8 is more effectively prevented. . For this reason, the occurrence of an error in the pattern position accuracy in the reticle 8 is suppressed, and a ULSI patterned with high alignment accuracy is obtained, so that the manufacturing yield of the ULSI can be significantly improved.

In the fourth embodiment, the other points are the same as those in the third embodiment.

Embodiment 5
FIG. 15 is a configuration diagram schematically showing a projection exposure apparatus according to Embodiment 5 of the present invention. 16 is a schematic side view showing the vicinity of the reticle in FIG. 15 in an enlarged manner, and FIG. 17 is a schematic plan view of FIG.

In FIGS. 15 to 17, the same reference numerals are given to the same or corresponding components as those in FIGS. 1 to 4 described above. The projection exposure apparatus 60 according to the fifth embodiment performs reduction projection by applying a gas whose temperature has been adjusted within the range of ± 0.1 ° C. of the set temperature to the reduction projection lens 10 instead of the first temperature adjustment unit 20. Only the point that a third temperature control unit 61 for adjusting the temperature of the lens 10 is provided is different from the projection exposure apparatus 1 of the first embodiment.

The third temperature control unit 61 includes a supply unit 62 for clean air from which temperature has been adjusted and dust has been removed, a housing 63 surrounding the reduction projection lens 10, and a pipe 64 connecting the supply unit 62 and the housing 63. The supply unit 62 includes a cooler 65, a heater 66, a blower 67, an ULPA filter 68, a temperature sensor (not shown), the cooler 65, and the like, similarly to the first temperature control unit 20 illustrated in FIG. It has a drive circuit (not shown) for the heater 66 and a control circuit (not shown) for controlling the drive circuit according to the output of the temperature sensor. In FIG. 16, reference numeral 69 denotes a reticle table.

At the time of projection exposure, as shown in FIGS. 16 and 17, clean air adjusted to within ± 0.1 ° C. of the set temperature by the third temperature control unit 61 is sent into the housing 63, and the reduced projection lens 10 is exposed. Flow along the outer circumference of.

As described above, according to the projection exposure apparatus 60 of the fifth embodiment, the reduction projection lens can be cooled by the clean air adjusted to within ± 0.1 ° C. of the set temperature, so that the projection exposure apparatus repeatedly emits UV light. Alternatively, the temperature of the reduction projection lens does not rise even when the deep UV light is irradiated, and the distortion distribution of this lens does not change. For this reason, it is possible to obtain a ULSI that is patterned with high alignment accuracy, and it is possible to significantly improve the production yield of the ULSI.

In the fifth embodiment, the other points are the same as those in the first embodiment.

Embodiment 6
FIG. 18 is a configuration diagram schematically showing a projection exposure apparatus according to the sixth embodiment of the present invention. 19 is a schematic side view showing the vicinity of the reticle in FIG. 18 in an enlarged manner, and FIG. 20 is a schematic plan view of FIG.

In FIGS. 18 to 20, the same or corresponding components as those in FIGS. 1 to 4 are denoted by the same reference numerals. In the projection exposure apparatus 70 according to the sixth embodiment, instead of the first temperature control unit 20, the cooling water whose temperature has been adjusted within the range of ± 0.1 ° C. of the set temperature flows around the reduction projection lens 10. Only the point that a fourth temperature control unit 71 for adjusting the temperature of the reduction projection lens 10 is provided is different from the projection exposure apparatus 1 of the first embodiment.

The fourth temperature control unit 71 includes a cooling water supply unit 72, a cooling plate 73 surrounding the reduction projection lens 10, and a pipe 74 spirally surrounding the cooling plate 73. The supply unit 72 includes a cooler 75, a heater 76, a pump 77, a temperature sensor (not shown), and a drive circuit for the cooler 75 and the heater 76, as in the second temperature control unit 40 shown in FIG. (Not shown) and a control circuit (not shown) for controlling the drive circuit according to the output of the temperature sensor.

At the time of the projection exposure, as shown in FIGS. 19 and 20, cooling water adjusted to within ± 0.1 ° C. of the set temperature by the fourth temperature control unit 71 is caused to flow through the pipe 74, and Adjust the temperature of the

As described above, according to the projection exposure apparatus 70 of the fifth embodiment, the reduction projection lens 10 is cooled with the cooling water adjusted within ± 0.1 ° C. of the set temperature, so that the projection exposure apparatus repeatedly Irradiation of light or deep UV light does not increase the temperature of the reduction projection lens, and the distortion distribution of this lens does not change. For this reason, it is possible to obtain a ULSI that is patterned with high alignment accuracy, and it is possible to significantly improve the production yield of the ULSI. In particular, in the case of cooling with cooling water, the cooling capacity is higher than in the case of cooling with clean air, so that the production yield can be further improved.

In the sixth embodiment, the other points are the same as those in the first embodiment.

Embodiment 7
FIG. 21 is a configuration diagram schematically showing a projection exposure apparatus according to Embodiment 7 of the present invention. FIG. 22 is an enlarged schematic side view showing the vicinity of the reduction projection lens in FIG. 21, and FIG. 22 is a schematic plan view in FIG.

In FIGS. 21 to 23, the same reference numerals are given to the same or corresponding components as those in FIGS. 18 to 20. The projection exposure apparatus 80 according to the seventh embodiment differs from the seventh embodiment only in that the periphery of the reduction projection lens 10 in the fourth temperature control unit 71 is surrounded by a housing 81. At the time of the projection exposure, as shown in FIGS. 22 and 23, the cooling water adjusted to within ± 0.1 ° C. of the set temperature by the fourth temperature control unit 71 is flown into the housing 81, and the reduced projection lens 10 Adjust the temperature of the

As described above, according to the projection exposure apparatus 80 of the seventh embodiment, since the reduction projection lens 10 is cooled with the cooling water adjusted within ± 0.1 ° C. of the set temperature, the projection exposure apparatus repeatedly Irradiation of light or deep UV light does not increase the temperature of the reduction projection lens, and the distortion distribution of this lens does not change. For this reason, it is possible to obtain a ULSI that is patterned with high alignment accuracy, and it is possible to significantly improve the production yield of the ULSI. In particular, in the case of cooling with cooling water, the cooling capacity is higher than in the case of cooling with clean air, so that the production yield can be further improved.

In the seventh embodiment, the other points are the same as the sixth embodiment.

Embodiment 8
FIG. 24 is a configuration diagram schematically showing a projection exposure apparatus according to the eighth embodiment of the present invention.

The projection exposure apparatus 90 of the eighth embodiment differs from the projection exposure apparatus of the first embodiment only in that it has both the first temperature control unit 20 of FIG. 1 and the third temperature control unit 61 of FIG. It is different from the device 1.

In the projection exposure apparatus 90 according to the eighth embodiment, since both the reticle 8 and the reduction projection lens 10 are temperature-controlled (normally cooled) within ± 0.1 ° C. of the set temperature, only the reticle is temperature-controlled. Also, compared to a case where only the reduction projection lens is temperature-adjusted, a ULSI patterned with much higher alignment accuracy can be obtained, and therefore, the manufacturing yield of the ULSI can be greatly improved.

In the eighth embodiment, the other points are the same as those in the first embodiment.

The combination of the temperature control unit of the reticle 8 and the temperature control unit of the reduction projection lens 10 is not limited to the above. For example, any combination of the reticle temperature control unit shown in FIGS. 1, 5, 8 and 12 and the lens temperature control unit shown in FIGS. 15, 18 and 21 is possible.

FIG. 1 is a configuration diagram schematically showing a projection exposure apparatus according to a first embodiment of the present invention. It is a block diagram which shows the temperature control unit of FIG. FIG. 2 is a schematic side view showing a flow of air applied to the reticle of FIG. 1. FIG. 4 is a schematic plan view of FIG. 3. FIG. 4 is a configuration diagram schematically showing a projection exposure apparatus according to a second embodiment of the present invention. FIG. 6 is a schematic side view showing a flow of air applied to the reticle of FIG. 5. FIG. 7 is a schematic plan view of FIG. 6. FIG. 9 is a configuration diagram schematically showing a projection exposure apparatus according to a third embodiment of the present invention. FIG. 9 is a schematic side view showing a flow of air applied to the reticle of FIG. 8 and a water cooling mechanism. FIG. 10 is a schematic plan view of FIG. 9. FIG. 9 is a configuration diagram illustrating the temperature control unit of FIG. 8. FIG. 9 is a configuration diagram schematically showing a projection exposure apparatus according to a fourth embodiment of the present invention. FIG. 13 is a schematic side view showing a flow of air applied to the reticle of FIG. 12 and a water cooling mechanism. FIG. 14 is a schematic plan view of FIG. 13. FIG. 13 is a configuration diagram schematically showing a projection exposure apparatus according to a fifth embodiment of the present invention. FIG. 16 is a schematic side view showing a flow of air applied to the reduction projection lens of FIG. 15. FIG. 17 is a schematic plan view of FIG. 16. FIG. 14 is a configuration diagram schematically showing a projection exposure apparatus according to a sixth embodiment of the present invention. FIG. 19 is a schematic side view showing a water cooling mechanism of the reduction projection lens of FIG. 18. FIG. 19 is a schematic plan view of FIG. 18. FIG. 15 is a configuration diagram schematically showing a projection exposure apparatus according to a seventh embodiment of the present invention. FIG. 22 is a schematic side view showing a water cooling mechanism of the reduction projection lens of FIG. 21. FIG. 23 is a schematic plan view of FIG. 22. FIG. 15 is a configuration diagram schematically showing a projection exposure apparatus according to an eighth embodiment of the present invention. It is a schematic side view of the conventional projection exposure apparatus. FIG. 26 is a configuration diagram schematically showing the projection exposure apparatus of FIG. 25. It is a conceptual diagram which shows an example of the exposure machine of FIG. It is a transmittance characteristic figure with respect to light of each wavelength.

Explanation of reference numerals

1, 30, 40, 50, 60, 70, 80, 90 Projection exposure apparatus, 1a housing, 7 light sources, 8 reticle, 9 reticle table, 10 reduction projection lens, 11 wafer, 12 wafer table and XY stage section, 20 1st temperature control unit, 22c, 22d blowing nozzle, 23a outlet, 31 cover, 41 second temperature control unit, 43 piping, 61 third temperature control unit, 63 housing, 71 fourth temperature control unit, 81 Housing.

Claims (10)

A projection exposure apparatus having a light source that irradiates light onto a reticle and a reduction projection lens that projects light from the light source transmitted through the reticle onto a wafer.
A first temperature control means for adjusting the temperature of the reduction projection lens by applying a gas whose temperature has been adjusted within a range of ± 0.1 ° C. of the set temperature to the reduction projection lens. Exposure equipment. 2. The apparatus according to claim 1, wherein the first temperature control means has a blower for sending gas toward the reduction projection lens and a discharger for discharging gas passing around the reduction projection lens. Projection exposure equipment. 3. The projection exposure apparatus according to claim 1, further comprising a cover surrounding the reduction projection lens, wherein the gas from the first temperature control unit flows into the cover. A second temperature adjusting means for adjusting the temperature of the reduction projection lens;
The second temperature control means includes a passage formed around the reduction projection lens, and a circulating means for flowing a liquid temperature-controlled within a range of ± 0.1 ° C. of a set temperature in the passage. 4. The projection exposure apparatus according to claim 1, wherein: In a projection exposure apparatus having a light source that irradiates light onto a reticle, and a reduction projection lens that projects light from the light source transmitted through the reticle onto a wafer,
Comprising a temperature control means for adjusting the temperature of the reduction projection lens,
The temperature control means includes a passage formed around the reduction projection lens, and a circulation means for flowing a liquid temperature-controlled within a range of ± 0.1 ° C. of a set temperature in the passage. Projection exposure apparatus. In the step of irradiating the reticle with light by the light source and projecting the light from the light source transmitted through the reticle onto the wafer using a reduction projection lens,
The temperature of the reduction projection lens is adjusted by applying a gas whose temperature has been adjusted within a range of ± 0.1 ° C. of a set temperature to the reduction projection lens using the first temperature control means. Exposure method. The blower of the first temperature control means sends gas toward the reduction projection lens, and discharges the gas passing around the reduction projection lens from the discharge section of the first temperature control means. 7. The projection exposure method according to claim 6, wherein: 8. The projection exposure method according to claim 6, wherein the gas from the first temperature control unit is caused to flow into a cover surrounding the reduction projection lens. The temperature of the reduction projection lens is adjusted by the second temperature adjustment means in a passage formed around the reduction projection lens, and the liquid is temperature-controlled within a range of ± 0.1 ° C. of the set temperature by the circulation means. The projection exposure method according to claim 6, wherein the projection exposure method is performed by flowing. In the step of irradiating the reticle with light by the light source and projecting the light from the light source transmitted through the reticle onto the wafer using a reduction projection lens,
The temperature control of the reduction projection lens by the temperature control means includes, in a passage formed around the reduction projection lens, a liquid whose temperature has been controlled within a range of ± 0.1 ° C. of a set temperature using a circulation means. A projection exposure method characterized by being carried out by flowing.

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