JP2007227543A - Immersion optical device, cleaning method, and immersion exposure method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an immersion optical device capable of making immersion exposure in appropriate environments, to provide a cleaning method, and to provide an immersion exposure method. <P>SOLUTION: The immersion optical device includes a light source 20, an optical lens system 33, a stage 34 for moving a specimen stage for mounting a specimen, a liquid feeder 36 for supplying an immersion liquid or a cleaning liquid to between the optical lens system 33 and the specimen, a liquid recovery device 39 for recovering the liquid, and an ozone gas supply 42 connected with the stage 34 or the liquid feeder 36 for supplying ozone gas to the cleaning liquid. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an immersion exposure apparatus that performs exposure by forming a liquid layer between an optical lens system and a sample, and an immersion exposure method using the same.

  Examples of the immersion optical apparatus that improves the resolution and the depth of focus by interposing a liquid between the sample and the optical lens system include an immersion microscope and an immersion exposure apparatus. The liquid immersion device includes a light source, a lens, a liquid supply device that supplies a liquid between the lens and the sample surface, and a liquid recovery device that recovers the liquid.

  An immersion exposure apparatus is an exposure apparatus used in a semiconductor lithography process. By interposing a liquid between a lens and a wafer, an NA (Numerical Aperture) can be increased and a depth of focus can be increased to 65 nm. It is expected to become a mainstream exposure apparatus in semiconductor manufacturing after half pitch (Non-Patent Document 1).

  Since the lens in contact with the liquid in the immersion optical device has been in contact with the liquid for a long time, the substance generated from the device, the sample surface, the liquid and the structure that guides the liquid reacts and adheres to the lens, and the lens surface is removed. There is a problem of clouding. The fogging of the lens surface is a problem due to performance degradation such as a decrease in resolution and a decrease in illuminance.

In addition, there has been a problem that the surface of the sample is contaminated by substances / contamination adhered to the lens or the like. Furthermore, there is a problem that exposure cannot be performed properly unless the liquid interposed between the lens and the wafer is exposed before and during exposure.
International Publication No. 99/49504 Pamphlet

  The present invention provides an immersion optical apparatus, a cleaning method, and an immersion exposure method capable of performing immersion exposure in an appropriate environment.

  An immersion optical apparatus according to a first aspect of the present invention includes a light source, an optical lens system, a stage for moving a sample stage on which a sample is mounted, and an immersion between the optical lens system and the sample. A liquid supply device for supplying a cleaning liquid or a cleaning liquid, a liquid recovery device for recovering the liquid, and supplying ozone gas to the cleaning liquid connected to the stage or the liquid supply device And an ozone gas supply unit.

  A cleaning method according to a second aspect of the present invention includes a light source, an optical lens system, a stage for moving a sample stage on which a sample is mounted, and an immersion lens between the optical lens system and the sample. Liquid immersion optical apparatus comprising: a liquid supplier for supplying a liquid or a cleaning liquid; a liquid collector for recovering the liquid; and an ozone gas supply unit connected to the stage or the liquid supplier In this cleaning method, the optical lens system is cleaned by supplying ozone gas from the ozone gas supply unit to the cleaning liquid and dissolving it.

  An immersion optical apparatus according to a third aspect of the present invention includes an immersion device between a light source, an optical lens system, a stage for moving a sample stage on which a sample is mounted, and the optical lens system and the sample. A liquid supply device for supplying a liquid for cleaning or a liquid for cleaning, a liquid recovery device for recovering the liquid, a dissolved gas concentration and a particle density in the liquid for immersion or the liquid for cleaning And a detector connected to the liquid collector for detecting at least one of the above.

  An immersion exposure method according to a fourth aspect of the present invention includes an immersion exposure between a light source, an optical lens system, a stage for moving a sample stage on which a sample is mounted, and the optical lens system and the sample. A liquid supply device for supplying an exposure liquid or a cleaning liquid; a liquid recovery device for recovering the liquid; and a dissolved gas concentration in the immersion exposure liquid or the cleaning liquid. An immersion exposure method in an immersion exposure apparatus comprising a detector connected to the liquid recovery device for detection, wherein the dissolved gas concentration detected by the detector is less than or equal to a predetermined concentration Then, immersion exposure is performed.

  An immersion exposure method according to a fifth aspect of the present invention includes an immersion exposure between a light source, an optical lens system, a stage for moving a sample stage on which a sample is mounted, and the optical lens system and the sample. A liquid supply device for supplying an exposure liquid or a cleaning liquid, a liquid recovery device for recovering the liquid, and detecting a particle density in the immersion exposure liquid or the cleaning liquid. An immersion exposure method in an immersion exposure apparatus comprising a detector connected to the liquid recovery device, wherein the liquid density is less than a predetermined density when the particle density detected by the detector is less than a predetermined density Perform immersion exposure.

  According to the present invention, it is possible to provide an immersion optical apparatus, a cleaning method, and an immersion exposure method that can perform immersion exposure in an appropriate environment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, elements having the same function and configuration are denoted by the same reference numerals.

(First embodiment)
FIG. 1 and FIG. 2 are diagrams showing the configuration during exposure and cleaning of the immersion exposure apparatus according to the first embodiment of the present invention, respectively.

  As shown in FIG. 1, a reticle stage 31 is disposed below the illumination optical system (light source) 20. A reticle 32 which is a photomask is installed on the reticle stage 31. The reticle stage 31 is movable in parallel. An optical lens system (projection lens system) 33 is disposed below the reticle stage 31. A sample stage 37 is disposed below the optical lens system 33.

  The semiconductor substrate 10 is installed on the sample table 37, and the height of the surface of the sample table 37 around the semiconductor substrate 10 is substantially the same as the height of the surface of the semiconductor substrate 10. The sample stage 37 moves in parallel and vertically together with the stage 34 and the semiconductor substrate 10. The stage 34 has a function of tilting with respect to the horizontal plane.

  A fence 35 is attached below the optical lens system 33. Next to the optical lens system 33, a liquid supply unit 36 that supplies water into the fence 35 and a liquid recovery unit 39 that collects water from the fence 35 are connected to the fence 35. The structures of the liquid supply unit 36 and the liquid recovery unit 39 are arbitrary and are not limited. The fence 35, the liquid supply device 36, and the liquid recovery device 39 are referred to as a head portion.

  At the time of exposure, the space between the substrate 10 and the optical lens system 33 in the region surrounded by the fence 35 is filled with a water layer. The exposure light emitted from the optical lens system 33 passes through the water layer and reaches the irradiation area. An image of the mask pattern (semiconductor element pattern) on the reticle 32 is projected onto the photoresist on the surface of the substrate corresponding to the irradiation region, and a latent image is formed.

  In a scan-and-repeat type exposure apparatus, not all the patterns on the photomask are transferred to the resist film at once, but a pattern in a predetermined range called an exposure field on a substrate plane conjugate to the photomask. Only is transferred at once. The pattern area on the photomask located in the exposure field is moved by moving the photomask and the substrate in a conjugate direction at a speed ratio corresponding to the magnification of the optical lens system with the exposure field as a reference. The entire pattern within a predetermined range on the photomask is projected onto the resist film.

  Since the movement distance of the photomask is larger than that of the substrate, the relative movement direction of the photomask and the substrate depending on the exposure order of the unit exposure areas, usually for the purpose of shortening the exposure process processing time by reducing the number of movements of the photomask. In general, each is in the opposite direction.

  Note that it is also possible to limit the pattern area on the photomask by an aperture called a mask blind. The unit exposure area of the latent image formed on the resist film corresponding to the mask pattern on the photomask is usually called an exposure shot.

  After several exposures, the upper part of the head in FIG. 1 moves to an area where the sample stage 37 on the stage 34 does not exist, and cleans the optical lens system 33 and the head. FIG. 2 shows the configuration of the immersion exposure apparatus during cleaning.

  A cleaning device 38 is connected to the liquid supply device 36, and the cleaning device 38 supplies, for example, ultrapure water as a cleaning liquid into the fence 35 via the liquid supply device 36. The cleaning device 38 further has a mechanism for generating a cavity in the ultrapure water that is a cleaning liquid. The liquid supplier 36 may supply ultrapure water.

  The cleaning device 38 generates a cavity in the ultrapure water by using, for example, a cavity jet nozzle, a venturi tube, or an ultrasonic device, using an ultrasonic wave, a water jet, a cavitation jet, or the like. The cavity is preferably a microcavity having an average diameter of 1 μm or less, a long lifetime, and difficult to disappear before reaching the substrate.

  As shown in FIG. 2, an ozone gas supply unit 42 is provided immediately below the area where the head portion of the stage 34 is in contact, and the ozone gas supply unit 44 supplies ozone gas directly into the fence 35. Yes.

  The ozone gas supplied from the ozone gas supply unit 44 is dissolved in the ultrapure water in the fence 35 to generate ozone water. Further, the optical lens system 33 and the head unit are cleaned by generating a cavity in the generated ozone water by the cleaning device 38. By using ozone water, cleaning without damaging the lens surface is possible.

  Ozone water can be stably dissolved in pure water under pressure or at a very low temperature, but vaporizes when the pressure is released and when the temperature rises. Therefore, when ozone water is drawn from a distance, unless the piping up to that point is kept pressurized, the concentration during cleaning cannot be controlled while keeping the concentration of ozone water constant, This is difficult to achieve.

  Therefore, as shown in FIG. 2, in the present embodiment, the ozone gas supply unit 42 is connected directly below the portion to be cleaned, and ozone gas is directly supplied to the region surrounded by the fence 35 and dissolved in ultrapure water. Ozonated water. In this way, cleaning is performed by generating a cavity in the ozone water in the fence 35 from the cleaning device 38 in a state where the ultrapure water is turned into ozone water.

  As another configuration of the present embodiment, as shown in FIG. 3, the ozone gas supply unit 42 is connected to the liquid supply unit 36, and ozone hydration in which the ozone gas is dissolved in ultrapure water is performed in the liquid supply unit 36. It may be done at. In any case, ozone gas is supplied in the immediate vicinity of the object to be cleaned such as the optical lens system 33, the stage 34, and the fence 35 with which the liquid used during the immersion exposure comes into contact. Accordingly, cleaning with ozone water that does not damage the lens surface can be performed while easily controlling the concentration of ozone water.

  In the case of the configuration shown in FIG. 3, it is possible to perform cleaning even at the exposure position as shown in FIG. Accordingly, the sample stage 37 and the like can be further cleaned by performing cleaning while moving the substrate 10 in the same manner as in the immersion exposure.

  As for the timing of cleaning, for example, when immersion exposure is performed for a certain time, cleaning processing is performed. In addition, the immersion exposure apparatus is provided with a measurement mechanism that measures the intensity of light (exposure wavelength is preferable) that passes through the optical lens system 33, and the light intensity measured by the measurement mechanism after the immersion exposure is less than a set value. A cleaning process may be performed. Furthermore, in addition to the measurement mechanism, a calculation mechanism for calculating the light intensity decrease amount from the light intensity information measured by the measurement mechanism and a calculation mechanism for calculating the cleaning time from the light intensity decrease amount are further provided. Cleaning may be performed according to the cleaning time.

  Moreover, after performing the cleaning process, rinsing may be performed with a rinsing liquid that does not include ozone and cavities, for example, water. By supplying the rinse liquid, the cleaning liquid remaining in the immersion exposure apparatus can be removed. For example, the rinsing process is performed by supplying water from the liquid supplier 36.

  As described above, the immersion exposure apparatus having the cleaning function facilitates the cleaning process, shortens the maintenance time, and improves the operating rate of the apparatus. Therefore, it becomes possible to reduce the manufacturing cost of the semiconductor element manufactured by the immersion exposure apparatus of this embodiment.

  Furthermore, by supplying ozone gas from the immediate vicinity of the region to be cleaned, it is possible to execute a cleaning process with ozone water that does not damage the lens surface with a certain quality. This cleaning process can remove the fogging of the lens and restore the resolution and illuminance. At the same time, it is possible to remove substances and contaminants attached to the lens and the apparatus member during the immersion exposure, and it is possible to suppress contamination of the sample surface.

(Second Embodiment)
FIG. 4 is a view showing a configuration at the time of exposure of the immersion exposure apparatus according to the second embodiment of the present invention. As in FIG. 1, an illumination optical system (light source) 20, reticle stage 31, reticle 32, optical lens system (projection lens system) 33, stage 34, fence 35, liquid supply device 36, and liquid recovery device 39 are provided. .

  In the present embodiment, a dissolved gas concentration meter 46 is further connected to the liquid recovery device 39. The dissolved gas concentration meter 46 can continuously monitor the dissolved gas concentration of the liquid for immersion exposure that has entered the liquid recovery device 39 even during exposure.

  At the time of exposure, the space between the substrate 10 and the optical lens system 33 in the region surrounded by the fence 35 is filled with a water layer. The exposure light emitted from the optical lens system 33 is a liquid for immersion exposure, for example, passes through a layer of water and reaches the irradiation area. An image of the mask pattern (semiconductor element pattern) on the reticle 32 is projected onto the photoresist on the surface of the substrate corresponding to the irradiation region, and a latent image is formed.

  During the immersion exposure, for example, when the exposure head exposes the edge of the wafer, the immersion exposure liquid may protrude from the wafer. In that case, there is a problem that air existing in the gap between the wafer cassette (sample stage) and the wafer is mixed in the liquid of the exposure head. This air may be dissolved in the liquid, and if it exceeds a certain amount, the air may be defoamed due to a temperature rise due to light irradiation during exposure, and the exposure may fail.

  Therefore, by monitoring whether or not the concentration of dissolved gas (for example, nitrogen, oxygen, etc.) is a predetermined concentration, for example, 0.1 ppm or less, the conditions under which the liquid used for immersion exposure can be appropriately exposed can be obtained. Can be determined.

  If it is determined during exposure that the above conditions are not satisfied, it is determined that an abnormality has been detected, and re-work (reseat) is performed, and the lithography process is performed again. In that case, the dissolved gas concentration is again monitored by the dissolved gas concentration meter 46, and when it is determined that the dissolved gas concentration satisfies a predetermined concentration, for example, 0.1 ppm or less and no abnormality is detected, Resume exposure.

  FIG. 5 is a flowchart showing an example of the immersion exposure method in this case. During exposure (step 501), the dissolved gas concentration of the liquid for immersion exposure is monitored by the dissolved gas concentration meter 46 at an appropriate timing or continuously, and the dissolved gas concentration is a predetermined concentration, for example, 0.1 ppm or less. It is determined whether or not the condition is satisfied (step 502). As a result, when the condition is not satisfied, the exposure is stopped (rework) (step 504), and the lithography process is performed again. If the condition is satisfied, the exposure is continued (step 503).

  Further, as shown in FIG. 6, an in-liquid particle counter 48 may be connected to the liquid recovery device 39 instead of the dissolved gas concentration meter 46. The in-liquid particle counter 48 monitors particles made of gas (bubbles) or dust that are laser scatterers in the liquid. It is monitored whether or not the particle density is a predetermined density, for example, 1 particle / ml or less. It is difficult for current particle counters to measure the actual particles and bubbles in the liquid separately. However, it goes without saying that both affect the exposure.

  When the edge of the wafer is subjected to immersion exposure, air existing in the gap between the wafer cassette (sample stage) and the wafer is mixed into the liquid for immersion exposure, for example, as described above. Or dust adhering to the wafer edge may be mixed due to dust generated by friction during wafer handling.

  Since exposure fails when there are many particles (gas bubbles) or dust that are laser scatterers in the liquid, it is possible to determine whether the liquid is in an appropriate exposure environment by monitoring these.

  FIG. 7 is a flowchart showing an example of the immersion exposure method in this case. During exposure (step 701), the particle density of the liquid for immersion exposure is monitored by the submerged particle counter 48 at an appropriate timing or continuously, and the particle density is a predetermined density, for example, 1 / ml or less. It is determined whether the condition is satisfied (step 702). As a result, when the condition is not satisfied, the exposure is stopped (rework) (step 704), and the lithography process is performed again. If the condition is satisfied, exposure is continued (step 703).

  Furthermore, as shown in FIG. 8, both the dissolved gas concentration meter 46 and the in-liquid particle counter 48 may be connected to the liquid recovery device 39. In this case, for example, the exposure is started only when both the condition that the dissolved gas concentration is 0.1 ppm or less and the condition that the particle density is 1 particle / ml or less are satisfied, and the exposure is performed when either condition is not satisfied. It is possible to perform immersion exposure in an appropriate exposure environment by stopping the operation.

  FIG. 9 is a flowchart showing an example of the immersion exposure method in this case. During the exposure (step 901), the dissolved gas concentration and the particle density in the liquid are monitored by the dissolved gas concentration meter 46 and the liquid particle counter 48 at an appropriate timing or continuously, and the dissolved gas concentration is a predetermined concentration, For example, it is determined whether or not a condition that the particle density is 0.1 ppm or less and the particle density is a predetermined density, for example, 1 particle / ml or less is satisfied (step 902). As a result, when the condition is not satisfied, the exposure is stopped (rework) (step 904), and the lithography process is performed again. If the condition is satisfied, exposure is continued (step 903).

  As described above, according to the present embodiment, it becomes possible to immediately detect that the liquid interposed between the lens and the wafer is no longer clean during exposure, so that the liquid immersion that may eventually fail may be detected. It is possible to quickly stop the exposure process and start the lithography process again. As a result, the working efficiency is improved, and the manufacturing cost of the manufactured semiconductor element can be reduced.

(Third embodiment)
FIG. 10 is a diagram showing a configuration during cleaning of an immersion exposure apparatus according to the third embodiment of the present invention. In the configuration of the present embodiment, a cleaning device 38 is connected to the liquid supply device 36 in addition to the configuration of the portion above the head portion of FIG. 4 according to the second embodiment. FIG. 10 shows a situation where the immersion exposure apparatus is operating in a region where the semiconductor substrate of the stage 34 does not exist.

  In this embodiment, in order to clean the optical lens system 33 and the head part after exposure, the part above the head part is moved to an area where the substrate of the stage 34 does not exist. Here, by supplying a cleaning liquid such as ozone water containing a cavity from the cleaning device 38 through the liquid supply device 36 into the fence 35, the optical lens in contact with the water supplied from the liquid supply device 36. The site containing the system 33 is washed.

  Thereafter, a cleaning liquid remaining in the immersion exposure apparatus is removed by supplying a rinsing liquid such as water into the fence 35. However, conventionally, there has been no means for confirming whether or not the cleaning liquid has been sufficiently removed by the rinse liquid. In the present embodiment, since the concentration of ozone contained in the cleaning liquid can be monitored by the dissolved gas concentration meter 46 connected to the liquid recovery device 39, whether or not the cleaning liquid has been sufficiently removed by the rinsing liquid. Can be confirmed. If it can be confirmed, immersion exposure is started, and if not, rinsing is continued as an abnormality is detected.

  Further, after the dissolved gas concentration meter 46 confirms that the ozone concentration in the rinse liquid is equal to or lower than the predetermined concentration, the monitoring is continued even when the liquid for immersion exposure is supplied from the liquid supplier 36. Thus, it may be determined whether or not the liquid is in an appropriate exposure environment. Alternatively, the ultrapure water, which is a liquid for immersion exposure, is continuously supplied as the rinse liquid, and at the same time, the dissolved gas concentration of the liquid is continuously monitored by the dissolved gas concentration meter 46, and becomes a predetermined concentration, for example, 0.1 ppm or less. In such a case, immersion exposure may be started. Thereby, immersion exposure can be performed in an appropriate exposure environment after cleaning.

  FIG. 11 is a flowchart showing an example of the immersion exposure method in this case. After washing with a washing liquid (step 1101), rinsing is performed with a rinse solution (step 1102). Then, continuously monitoring the dissolved gas concentration of the rinsing liquid with the dissolved gas concentration meter 46 while performing appropriate timing or rinsing, and whether a predetermined concentration, for example, 0.1 ppm or less is satisfied It is determined whether or not (step 1103). As a result, if the condition is not satisfied, rinsing is continued, and if the condition is satisfied, exposure is started (step 1104).

  Further, as shown in FIG. 12, instead of the dissolved gas concentration meter 46, an in-liquid particle counter 48 may be connected to the liquid recovery device 39, and the particle density is a predetermined density, for example, 1 / ml or less. In the case where this condition is satisfied after cleaning, immersion exposure may be started.

  FIG. 13 is a flowchart showing an example of the immersion exposure method in this case. After washing with a washing liquid (step 1301), rinsing is performed with a rinse liquid (step 1302). Then, continuously monitoring the particle density of the rinsing liquid with the in-liquid particle counter 48 while performing appropriate timing or rinsing, and whether a predetermined density, for example, 1 month / ml or less is satisfied It is determined whether or not (step 1303). As a result, if the condition is not satisfied, rinsing is continued, and if the condition is satisfied, exposure is started (step 1304).

  Furthermore, as shown in FIG. 14, both the dissolved gas concentration meter 46 and the in-liquid particle counter 48 may be connected to the liquid recovery device 39. In this case, for example, when exposure is started only when both the condition that the dissolved gas concentration is 0.1 ppm or less and the condition that the particle density is 1 particle / ml or less are satisfied after cleaning, and either condition is not satisfied In such a case, the immersion exposure can be executed in an appropriate exposure environment without starting the exposure.

  FIG. 15 is a flowchart showing an example of the immersion exposure method in this case. After washing with a washing liquid (step 1501), rinsing is performed with a rinse solution (step 1502). Thereafter, continuously monitoring the dissolved gas concentration of the rinsing liquid by the dissolved gas concentration meter 46 and the particle density of the rinsing liquid by the in-liquid particle counter 48 while performing appropriate timing or rinsing, respectively. It is determined whether or not both the condition of 0.1 ppm or less, for example, and the condition of a predetermined density, for example 1 / ml or less, are satisfied (step 1503). As a result, if the condition is not satisfied, rinsing is continued, and if the condition is satisfied, exposure is started (step 1504).

  Further, when ozone water is used as the cleaning liquid, the ozone gas supply unit 42 and the ozone gas supply unit 44 are connected to the liquid supply unit 36 as shown in FIG. In addition, a dissolved gas concentration meter 46 and a liquid particle counter 48 may be further provided.

  Thus, cleaning with ozone water that does not damage the lens surface can be performed more easily with the ozone water concentration kept constant. At the same time, the dissolved gas concentration meter 46 and the in-liquid particle counter 48 can monitor the ozone concentration and particles containing ozone in the form of bubbles (bubbles). Accordingly, it is possible to perform immersion exposure after confirming that an appropriate exposure environment is obtained after cleaning.

  The specifications of the particle density and dissolved gas concentration shown in the second and third embodiments also differ depending on the immersion exposure conditions (liquid flow rate, flow method, etc.) used.

  In the first to third embodiments described above, examples of the immersion exposure apparatus have been described. However, the present invention can also be applied to an immersion type measurement apparatus that measures the surface of a sample.

  That is, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention in the implementation stage. Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and the effect described in the column of the effect of the invention Can be extracted as an invention.

1 is a diagram showing a configuration during exposure of an immersion exposure apparatus according to a first embodiment of the present invention. FIG. 2 is a diagram showing a configuration during cleaning of the immersion exposure apparatus according to the first embodiment of the present invention. FIG. 5 is a view showing another configuration during cleaning of the immersion exposure apparatus according to the first embodiment of the present invention. The figure which shows the structure at the time of exposure of the immersion exposure apparatus concerning the 2nd Embodiment of this invention. The figure which shows the flowchart of the immersion exposure method concerning the 2nd Embodiment of this invention. The figure which shows another structure at the time of exposure of the immersion exposure apparatus concerning the 2nd Embodiment of this invention. The figure which shows another flowchart of the immersion exposure method concerning the 2nd Embodiment of this invention. The figure which shows another structure at the time of exposure of the immersion exposure apparatus concerning the 2nd Embodiment of this invention. The figure which shows another flowchart of the immersion exposure method concerning the 2nd Embodiment of this invention. The figure which shows the structure at the time of the washing | cleaning of the immersion exposure apparatus concerning the 3rd Embodiment of this invention. The figure which shows the flowchart of the immersion exposure method concerning the 3rd Embodiment of this invention. The figure which shows another structure at the time of the washing | cleaning of the immersion exposure apparatus concerning the 3rd Embodiment of this invention. The figure which shows another flowchart of the immersion exposure method concerning the 3rd Embodiment of this invention. The figure which shows another structure at the time of the washing | cleaning of the immersion exposure apparatus concerning the 3rd Embodiment of this invention. The figure which shows another flowchart of the immersion exposure method concerning the 3rd Embodiment of this invention. The figure which shows the structure at the time of the washing | cleaning by ozone water of the immersion exposure apparatus concerning the 3rd Embodiment of this invention. The figure which shows another structure at the time of the washing | cleaning by ozone water of the immersion exposure apparatus concerning the 3rd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Semiconductor substrate, 20 ... Illumination optical system, 31 ... Reticle stage, 32 ... Reticle, 33 ... Optical lens system (projection lens system), 34 ... Stage, 35 ... Fence, 36 ... Liquid supply device, 37 ... Sample stand, DESCRIPTION OF SYMBOLS 38 ... Washing device, 39 ... Liquid recovery device, 42 ... Ozone gas supply part, 44 ... Ozone gas supply device, 46 ... Dissolved gas concentration meter, 48 ... Liquid particle counter, 501-504, 701-704, 901-904, 1101 ˜1104, 1301-1304, 1501-1504... Step.

Claims (6)

  A liquid source for supplying an immersion liquid or a cleaning liquid between the light source, the optical lens system, a stage for moving a sample stage on which the sample is mounted, and the optical lens system and the sample And a liquid recovery device for recovering the liquid, and an ozone gas supply unit connected to the stage or the liquid supply device for supplying ozone gas to the cleaning liquid. Immersion optical device.   A liquid source for supplying an immersion liquid or a cleaning liquid between the light source, the optical lens system, a stage for moving a sample stage on which the sample is mounted, and the optical lens system and the sample A cleaning method in an immersion optical apparatus comprising: a container; a liquid recovery device for recovering the liquid; and an ozone gas supply unit connected to the stage or the liquid supply device. A cleaning method, wherein ozone gas is supplied and dissolved in a cleaning liquid to clean the optical lens system.   A liquid source for supplying an immersion liquid or a cleaning liquid between the light source, the optical lens system, a stage for moving a sample stage on which the sample is mounted, and the optical lens system and the sample And a liquid recovery device for recovering the liquid, and connected to the liquid recovery device for detecting at least one of a dissolved gas concentration and a particle density in the immersion liquid or the cleaning liquid. An immersion optical device comprising a detector.   A light source, an optical lens system, a stage for moving a sample stage on which a sample is mounted, and a liquid for supplying a liquid for immersion exposure or a cleaning liquid between the optical lens system and the sample A supply, a liquid recovery device for recovering the liquid, and a detector connected to the liquid recovery device for detecting a concentration of dissolved gas in the liquid for immersion exposure or the liquid for cleaning; An immersion exposure method in an immersion exposure apparatus comprising: when the dissolved gas concentration detected by the detector is equal to or lower than a predetermined concentration, the immersion exposure method is performed. .   A light source, an optical lens system, a stage for moving a sample stage on which a sample is mounted, and a liquid for supplying a liquid for immersion exposure or a cleaning liquid between the optical lens system and the sample A supply device, a liquid recovery device for recovering the liquid, and a detector connected to the liquid recovery device for detecting a particle density in the immersion exposure liquid or the cleaning liquid. An immersion exposure method in an immersion exposure apparatus provided, wherein the immersion exposure is performed when a particle density detected by the detector is equal to or lower than a predetermined density.   6. The immersion exposure method according to claim 4, wherein the optical lens system is cleaned before detection by the detector.

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