JP2007123686A - Driving apparatus and driving method, position detecting apparatus and aligner using it, and device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the heat generation in a driving system in a driving apparatus by a simple means. <P>SOLUTION: The driving apparatus has a driving mechanism having a motor and a current supplying means for supplying an exciting current to the exciting winding of the motor. Further, the apparatus is provided with a means for detecting the exciting current for the motor or the current supplied to the driving mechanism, and a means for determining whether the detected current exceeds a first predetermined value and a second predetermined value larger than the first one respectively. The exciting current is limited or the apparatus is stopped in accordance with the detected current value. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention provides an apparatus and method for driving a drive mechanism having a motor, a position detection apparatus and an exposure apparatus using the same, and a device manufacturing method using the exposure apparatus. The present invention is particularly suitable when applied to a location that is susceptible to thermal influence in an exposure apparatus or the like, or a location where the drive mechanism is not visible.

The exposure apparatus forms and projects an original (reticle or photomask) pattern onto a substrate (wafer) via a projection optical system.
The exposure apparatus is required to have very high position detection accuracy. In the position detection means or the like provided in the exposure apparatus, a stepping motor drive mechanism is provided or configured to drive the optical components and the like with high accuracy. The thermal effect of the stepping motor drive mechanism causes thermal deformation of the exposure apparatus or fluctuation in the space, which affects the position detection accuracy of the exposure apparatus. As a stepping motor drive mechanism, one described in Patent Document 1 is known.

  As a conventional technique for suppressing the heat generation of the stepping motor drive mechanism, there is a method of configuring a cooling mechanism using a liquid such as water as a coolant in the drive mechanism. However, in order to configure the cooling mechanism, the space that configures the cooling mechanism and the piping that supplies the refrigerant are required. Therefore, a plurality of motor drive mechanisms are configured in a narrow space as described in Patent Documents 2 and 3. The position detection means is difficult to configure.

  As another conventional technique, there is a method of installing a heat sink or a heat pipe in the drive mechanism in order to suppress heat generation of the stepping motor drive mechanism. However, the heat conductive sheet used when the heat sink or the heat pipe is brought into contact with the drive mechanism uses many materials that affect the optical system as described in Patent Document 4, and cannot be used near the optical system. When applied to the position detecting means described above, the stepping motor drive unit is configured in the purge space, so that a configuration for heat transport to the outside is required and the configuration is difficult.

  There is also a method of configuring a heat exhaust duct in the stepping motor drive unit. However, when applied to the position detection means and the like, since the stepping motor drive unit is configured in the purge region, it is difficult to configure a heat exhaust duct.

  Further, in the position detection means and the like, the stepping motor drive unit is configured in the purge region, and the drive unit cannot be visually confirmed from the outside. Accordingly, since it is impossible to determine from the outside whether a malfunction has occurred in the drive unit when a detection error occurs, the purge must be opened and visually observed. However, when the drive mechanism is confirmed, the purge is released once, so that there is a problem that it takes time to purge again.

In addition, in order to make a visual check even in a stepping motor drive mechanism that is not in the purge region, it is necessary to open the chamber surrounding the exposure apparatus. Therefore, there is a problem that it takes time to stabilize the atmosphere in the chamber once the chamber is opened.
The inability to visually check the drive unit from the outside also has a problem in terms of determining the maintenance time. That is, there is a problem in the operation method because it is necessary to specify the maintenance time uniformly in a certain period without distinguishing between a device that hardly uses the drive mechanism and a device that frequently uses the drive mechanism.
JP 2003-111377 A JP 2004-193160 A Japanese Patent Laid-Open No. 2004-238661 JP 2003-203847 A

  The present invention has been made in view of the problems in the above-described conventional examples. An object of the present invention is to make it possible to suppress heat generation of a drive system by simple means. Another object of the present invention is to enable monitoring of a drive system malfunction and maintenance time from the outside without opening the purge or opening the chamber.

  In order to solve the above-described problems, a drive device according to the present invention includes a drive mechanism having a motor and current supply means for supplying an excitation current to the excitation winding of the motor, and an excitation current for the motor or supply to the drive mechanism. Means for detecting current. The first drive device according to the present invention further includes means for determining whether or not the detected current exceeds a first predetermined value and a second predetermined value larger than the first predetermined value.

  A second drive device according to the present invention includes means for setting an excitation current value or a limit value to be energized to the motor in the drive device of the present invention. And a means for controlling an exciting current energized from the current supply means to the motor based on an output of the setting means. The control means controls the excitation current supplied to the motor from the current supply means so as to coincide with the excitation current conduction value set in the setting means or to limit the excitation current limit value.

The drive method of the present invention is a drive method of a drive mechanism having a motor and a current supply means for supplying an excitation current to the excitation winding of the motor, and the excitation current of the motor or the supply current to the drive mechanism is previously determined. A step of providing a detecting means;
The first driving method according to the present invention includes a step of measuring the excitation current of the motor or the supply current to the drive mechanism using the detection means. Moreover, when the measured electric current exceeds the 1st predetermined value, the process of determining with the maintenance time of the said drive mechanism having arrived is provided. Further, the method includes a step of determining that the drive mechanism has failed when a second predetermined value larger than the first predetermined value is exceeded.

  According to a second driving method of the present invention, the driving method of the present invention includes a step of measuring or estimating the excitation current capable of generating the required torque of the driving mechanism. Then, a step of determining an excitation current to be supplied to the motor from the current supply means or a limit value thereof in consideration of a predetermined safety factor for the excitation current is provided. A step of measuring the excitation current of the motor or the supply current to the drive mechanism using the detection means; And a step of controlling the exciting current energized from the current supply means to the motor or the limit value thereof to coincide with the exciting current energizing value determined in the determining step or to limit the exciting current limit value. .

According to the present invention, the state of the drive mechanism can be monitored by monitoring the excitation current value of the motor. Therefore, an emergency stop or a warning can be generated according to the state of the drive mechanism. Therefore, when the present invention is applied to an exposure apparatus, it is possible to prevent a product such as an IC chip from being forged.
According to the present invention, the excitation current is automatically controlled according to the load of the drive mechanism, and the minimum excitation current is applied. Therefore, the drive mechanism can be operated with a low torque margin without considering the torque margin expected in the conventional drive mechanism. When the present invention is applied to an exposure apparatus, thermal deformation of the exposure apparatus can be reduced, so that highly accurate position detection can be performed.

  According to the exposure apparatus to which the present invention is applied, since it is possible to monitor the malfunction and life of the drive mechanism from the outside without opening the purge atmosphere and chamber atmosphere, it is possible to reduce the re-purge time and purge release work, which is beneficial for the operation of the apparatus. It is. Furthermore, since the opportunity to release the purge atmosphere is reduced, the opportunity for the optical system element in the purge atmosphere to come into contact with the air is reduced. As a result, the opportunity for the optical element to come into contact with harmful gases in the atmosphere is reduced, and contamination of the optical element can be reduced.

When the present invention is applied to an immersion exposure apparatus, the motor drive unit configured in the liquid immersion region or the motor drive unit configured in the housing in contact with the liquid immersion region does not discard the liquid and is driven by the motor. It is possible to grasp the state of the part. Due to this effect, there is an advantage in apparatus operation that the number of times of discharging and inserting the liquid is reduced.
When the present invention is configured in an EUV exposure apparatus, the motor driving unit configured in the vacuum region or the motor driving unit configured in the housing that contacts the vacuum region grasps the state of the motor driving unit without opening the vacuum region. It is possible. This effect has an advantage in apparatus operation that the number of times of vacuum purging is reduced.

The embodiments of the present invention are listed below.
In the second drive device according to the present invention, the energization amount control by the control means is opened or an energization value sufficiently larger than a normal energization amount is replaced with the set excitation current energization value or limit value. Give to the means. Then, it is determined whether or not the current detected by the detection means at that time exceeds a first predetermined value and a second predetermined value larger than the first predetermined value. Thereby, it is possible to know the maintenance timing of the drive mechanism and the malfunction of the drive mechanism.

For example, when the excitation current of the motor or the current supplied to the drive mechanism exceeds the first predetermined value, a warning is given that the maintenance timing of the drive mechanism has arrived. Further, when the excitation current of the motor or the supply current to the drive mechanism exceeds the second predetermined value, a warning of the malfunction of the drive mechanism is given. The warning is performed by displaying characters or marks on the display device, warning sound, warning light, or the like.
Further, when the excitation current of the motor or the current supplied to the drive mechanism exceeds the second predetermined value, the drive mechanism or the device equipped with the drive mechanism may be stopped.

Preferably, the motor has one or more excitation windings, and the current supply means supplies current to each excitation winding individually.
The present invention is particularly preferably applied when the drive mechanism is disposed in the purge space. The purge space is, for example, an immersion area in the immersion exposure apparatus or a vacuum area in the EUV exposure apparatus.

Embodiments of the present invention will be described below with reference to the drawings.
[First embodiment]
FIG. 1 shows a schematic configuration of an exposure apparatus according to an embodiment of the present invention. The exposure apparatus includes an original stage 2 that holds an original (reticle) 1, a substrate stage 6 that holds a substrate (wafer) 4, a light source unit 10, an illumination optical system, and a projection optical system 7. The exposure light emitted from the light source unit 10 is guided to the original by an illumination optical system. The guided exposure light is transmitted through the original, and a pattern formed on the original is projected onto the wafer via the projection optical system 7. Hereinafter, each component will be further described.

The light source unit 10 generates exposure light. In order to cope with the improvement in the degree of integration and fineness of semiconductor devices, the wavelength of exposure light has been shortened. Currently, ultraviolet ray i-line (wavelength 365 nm), KrF excimer laser light (wavelength 248 nm), ArF excimer laser light (wavelength 193 nm), and F ₂ laser light (wavelength 157 nm) are put to practical use. Furthermore, the use of EUV, soft X-rays and the like having a short wavelength is planned. Further, in order to cope with the improvement in throughput, the use of exposure light with higher output is being promoted even in the same wavelength region.

Especially in exposure apparatuses that use short wavelength lasers such as KrF excimer laser, ArF excimer laser, and F ₂ laser as exposure light, since the attenuation of exposure light is large, light is guided in an almost sealed space with an inert gas. Yes.
Also in an exposure apparatus that uses i-line as exposure light, a substantially sealed space is guided to isolate the optical element from the optical element contaminants.

The light beam emitted from the light source unit 10 is incident on the casing A of the illumination optical system mainly composed of members from the light source unit 10 to the collimator lens 25. The housing A has propagation lenses 11 and 12.
The light beam that has passed through the propagation lens 12 enters the housing B. In the case B, a beam shaping optical system 13 for shaping a parallel light beam from the light source unit 10 into a desired beam shape and making it incoherent is disposed. In addition, a light amount adjustment system 14 for adjusting the amount of light, which is composed of an optical member having a plurality of attenuation ratios for attenuating light from a light source such as an ND filter, is disposed. The light amount adjustment system 14 can switch between a plurality of optical members by a motor drive mechanism, and can automatically perform optimum light amount adjustment.

  The housing B further includes a switching mirror 16 and a lens 17 for guiding light to the first position detection means 15 (15a, 15b, 15c). A detailed description of the first position detection means 15 will be given later. During the exposure process, the switching mirror 16 is switched so that the light beam enters the housing C. When using the first position detecting means 15, the switching mirror 16 is switched so as to guide the light to the first position detecting means 15. The switching mirror 16 is switched by a motor drive mechanism (not shown).

  The light beam emitted from the housing B enters the housing C. The housing C includes a condenser lens 18 that collects light, a light integrator 19, a mirror 20, a condenser lens 21, and an illumination method switching means 22. The illumination method switching means 22 has a motor drive mechanism, and can change the numerical aperture ratio σ between the exposure illumination optical system and the projection optical system.

The light beam emitted from the housing C enters the housing D. A masking blade 23 is disposed in the vicinity of the slit opening surface. The masking blade 23 functions as an aperture stop that exposes only a necessary area for each shot on the substrate 4.
The light beam emitted from the housing D enters the housing E. The housing E has a masking imaging system 24 and a collimator lens 25. The masking imaging system 24 images the light beam from the aperture shape formed by the masking blade 23 and guides it to the collimator lens 25. The collimator lens 25 converts the light beam exiting the slit into a parallel light beam and uniformly illuminates an area on the surface of the original 1.

The light beam transmitted through the original 1 enters the projection optical system 7. The projection optical system 7 includes a motor drive mechanism (not shown) that can adjust the light flux to an arbitrary NA and a aberration correction.
The projection optical system 7 forms and exposes an original pattern onto the substrate 4 held on the substrate stage 6.

  The substrate stage 6 is driven by an optical axis direction (Z direction) of the projection optical system 7 and an XY direction orthogonal to the optical axis, a rotation direction around the optical axis (θ direction), a rotation direction around the X axis, and a Y axis. It can move in the direction of rotation. A linear motor is used as the driving means, but other driving means may be used. A movable mirror 9 that reflects the beam from the laser interferometer 8 is fixed to the substrate stage 6. The position and movement amount of the substrate stage 6 are sequentially measured by the laser interferometer 8. With such a configuration, the substrate 4 can be matched with the image plane of the projection optical system 7.

  A mechanism for aligning the substrate with the focal position of the pattern will be described. A reference plate (reference portion) 3 on which marks are formed is fixed on the original stage. The reflective surface of the reference plate 3 is substantially the same height as the reflective surface of the original 1. Similarly, a reference plate (reference portion) 5 on which marks are formed is fixedly provided on the substrate stage 6. The reflective surface of the reference plate 5 is substantially the same height as the reflective surface of the substrate 4.

  A focus detection mechanism 26 is provided as means for detecting the surface position of the original 1. The focus detection mechanism 26 includes an irradiation unit and a detection unit. Non-exposure light is emitted from an oblique direction to the surface of the original plate 1 (or the surface of the reference plate 3) from the irradiation unit, and the reflected light is detected by the detection unit. For example, a plurality of light receiving elements are used as the detection unit. Here, the light receiving surface of each light receiving element and the reflection point of each light beam of the original 1 are arranged so as to be substantially conjugate. With such a configuration, the positional deviation of the original 1 (or the reference plate 3) in the optical axis direction of the projection optical system 7 is measured as a positional deviation in the detection unit.

  A focus detection system 27 is provided as means for detecting the surface position of the substrate 4. The focus detection system 27 includes an irradiation unit and a detection unit. Non-exposure light is emitted from an oblique direction to the surface of the substrate 4 (or the surface of the reference plate 5) from the irradiation unit, and the reflected light is detected by the detection unit. For example, a plurality of light receiving elements are used as the detection unit. Here, the light receiving surface of each light receiving element and the reflection point of each light beam on the substrate 4 are arranged so as to be substantially conjugate. With such a configuration, the displacement of the substrate 4 (or the reference plate 5) in the optical axis direction of the projection optical system 7 is measured as a displacement in the detection unit.

Here, when the projection optical system 7 absorbs exposure heat or the surrounding environment fluctuates, the focal position of the projection optical system 7 fluctuates, and the measurement reference (origin) and focal plane of the focus detection mechanism change. An error occurs in the relationship. Therefore, the first position detecting means 15 for correcting such an error is provided.

The position detection means 15 includes three position detection systems (15a to 15c). Each of the position detection systems 15a to 15c includes a motor drive mechanism for detecting within an arbitrary detection range. The position detection systems 15a and 15b can move the detection range in a direction (X direction in the figure) substantially orthogonal to the scanning direction of the original stage 2 by a motor drive mechanism. The position detection system 15c can move the detection range in a direction substantially parallel to the scanning direction of the original stage 2 (Y direction in the figure). Each detection mechanism also includes a motor drive mechanism for measuring the focal position, in addition to the motor drive mechanism for moving the detection range.

The exposure light guided to the first position detection unit 15 by the switching mirror 16 is guided to the detection mechanisms 15a to 15c. Here, in the case where light having a short wavelength such as KrF excimer laser, ArF excimer laser, or F ₂ laser is used as the exposure light, the first position detector 15 is sealed with an inert gas in order to suppress the attenuation of the exposure light. It is preferable to arrange in the space formed.

  The position detection means 15 illuminates the vicinity of the mark on the reference plate 3 using the guided light. The detection system to be used can be arbitrarily selected from the detection systems 15a to 15c. At least one or more optical systems in the position detection unit 15 are driven in the detection optical axis direction so that the detection focal plane of the position detection unit 15 is aligned with the mark on the reference plate 3. Next, the substrate stage is driven up and down in the optical axis direction (Z direction) in the vicinity of zero preset by the focus detection system 27.

  During the above driving, the reference plate 5 is positioned almost directly below the projection optical system 7. The light transmitted through the mark on the reference plate 3 passes through the projection optical system 7 and irradiates the reference plate 5. The light reflected by the reference plate 5 passes through the projection optical system 7 again and enters the light receiving portion of the position detecting means 15 via the reference plate 3. The reference plate 5 can be focused on the reference plate 3 by measuring the amount of light incident on the light receiving unit.

  The position detection means 15 has not only the above-described focusing function but also a function of detecting the positions of the reference plate 3 and the reference plate 5 in the XY directions. The detection result is an element for calculating the baseline of the off-axis microscope 28. The base line is the distance between the shot center when aligning the substrate and the shot center when exposing (the optical axis of the projection optical system).

  The off-axis microscope 28 is a non-TTL (Through The Lens) microscope that uses non-exposure light, and is a microscope that detects the position of the alignment mark on the substrate 4. The off-axis microscope 28 constitutes a motor drive mechanism that can select a plurality of aperture stops, and can select an arbitrary illumination mode.

An example of baseline measurement of the off-axis microscope 28 is shown.
When performing this measurement, at least one of the detection systems 15a, 15b, and 15c of the first position detection means 15 is driven from the standby position during the exposure process to the detection range of each detection system. The master reference mark formed on the reference plate 3 is moved into the detection range by driving the master stage 2. The substrate reference mark formed on the reference plate 5 is moved into the detection range by driving the substrate stage 6.

  The relative deviation amount between the original reference mark and the substrate reference mark is detected by at least one detection system of the position detection means 15 (first step). After the first step is completed, the reference substrate mark is moved to the detection range of the off-axis microscope 28. A relative deviation amount between the reference substrate mark and the microscope reference mark fixed to the off-axis microscope 28 is detected (second step). Based on the detection results of the first step and the second step, the baseline of the off-axis microscope 28 is calculated, and the baseline of the off-axis microscope 28 is corrected. After the baseline correction, the detection system of the position detection means 15 retracts to the standby position during the exposure process.

  In the present invention, a stepping motor is used for at least one of the motor drive mechanisms described above. In particular, since the motor drive mechanism used in the position detection means 15 requires high-precision feed position accuracy, it is preferable to use a stepping motor. A motor drive mechanism that does not use a stepping motor can have various configurations such as a DC brushless motor drive mechanism and an ultrasonic motor drive mechanism.

  The motor drive mechanism in this embodiment further includes a controller 50, which controls the coil excitation current of the stepping motor according to the load. That is, when the load increases, the exciting current is automatically increased to eliminate the torque fluctuation. As such a motor drive mechanism, for example, “PB servo system” of Sanyo Denki Co., Ltd. can be cited.

  As the motor drive mechanism, a motor device described in a patent document (Japanese Patent Laid-Open No. 2003-111377) may be used. This motor apparatus has two or more divided excitation windings in which one or more excitation windings of a motor are composed of one or more winding portions with a winding portion wound around one magnetic pole portion as a minimum unit. Consists of. In addition, the excitation current energization circuit is provided for each of the two or more divided excitation windings constituting the excitation winding of one phase or more, and the excitation current energizing circuit individually supplies the excitation current to the corresponding divided excitation windings. The individual excitation current conduction circuit is provided. With such a configuration, a reduction in torque can be suppressed even in a high-speed operation region.

  Furthermore, the controller 50 has a function of monitoring the coil excitation current of the stepping motor. This will be described with reference to FIG. In FIG. 2, the vertical axis represents the motor excitation current value, and the horizontal axis represents the usage time. If the motor drive mechanism is normally driven, the drive load is substantially constant, and therefore, the motor drive mechanism is driven with a substantially constant excitation current. However, if dust adheres to the drive shaft or a load occurs that causes the motor to step out due to some malfunction, the drive load increases rapidly, and the excitation current increases as the drive load increases (drive) Curve a).

  The controller 50 is set with a warning current value and an emergency stop current value. When the excitation current value increases and exceeds the warning current value, a warning is issued via the console of the exposure apparatus. When the excitation current exceeds the emergency stop current value, the drive mechanism is automatically stopped. Here, only the emergency stop current value may be set without setting the warning current value.

  Further, the present invention is not limited to the above-described sudden failure, and it is possible to cope with an increase in excitation current due to deterioration of the drive mechanism over time. In general, the excitation current gradually increases due to deterioration of the drive mechanism with time. Therefore, when the exciting current value exceeds the warning current value, the maintenance operator is notified to the apparatus operator via the exposure apparatus console. When the apparatus operator neglects maintenance, the drive mechanism is automatically stopped when the exciting current value exceeds the emergency stop current value.

  Thus, the motor drive mechanism in the present embodiment is characterized in that it automatically controls the current of the stepping motor in accordance with the load and monitors the current. Further, the stepping motor has one or more exciting windings, and can be individually energized in accordance with the load. This is effective for confirming the state of the drive mechanism in an apparatus such as an exposure apparatus in which components are placed in the chamber and cannot be seen from the outside, and opening the chamber affects the operating rate. It is.

In addition, when the above-described motor drive mechanism is used, the motor can be operated with a torque margin lower than that in the prior art. This will be described below.
Conventionally, motor drive mechanisms have set exciting current values that allow for various errors using fixed resistors on a circuit board. Error factors include differences in specifications between the manufacturing plant and the device manufacturer, errors in the current value after adjustment of the drive mechanism and after installation in the exposure device, and errors in resistance when replacing the drive substrate in the market. There is.

  The drive mechanism of this embodiment automatically controls the excitation current according to the load of the drive mechanism and supplies the minimum excitation current. Therefore, it is possible to operate the drive mechanism with a low torque margin without considering the torque margin expected with the conventional drive mechanism. The excitation current is calculated, for example, at the time of manufacture of the exposure apparatus, at the time of shipment from the factory, at the time of maintenance, or is set by estimating from the required torque. For example, when the excitation voltage immediately before the drive mechanism stops when the applied voltage to the motor or the limit value of the excitation current is decreased, the excitation current detection means observes the excitation current, and the excitation current immediately before the stop is Calculate by multiplying by the rate.

FIG. 3 is a diagram for explaining the outline of the present embodiment. FIG. 3 shows a comparison between this embodiment and a conventional configuration.
In the conventional apparatus, the fixed resistance value of the drive control board is set so as to be in the vicinity of the excitation current a with a margin in consideration of machine differences. In the conventional apparatus, since the exciting current is set with a fixed resistance value, for example, when the supply voltage is high, an unnecessary exciting current Δc is energized to the motor, and extra heat is generated in the motor drive mechanism. . As a result, thermal deformation of the object is caused in the baseline measurement or the like, and an error in the measurement value is generated. In the second position detection means and the third position detection means, the detection optical path fluctuates due to heat generation during driving, causing a measurement error.

  In this embodiment, since the exciting current can be set near the minimum exciting current b corresponding to the required torque, the exciting current value of Δc can be reduced as compared with the conventional device, and errors due to heat generation as described above can be reduced. it can.

The drive mechanism according to the above-described embodiment can monitor the state of the drive means by monitoring the excitation current value of the motor. Further, an emergency stop or warning can be generated according to the state of the drive mechanism. Therefore, when this driving means is applied to an exposure apparatus, it is possible to prevent a product such as an IC chip from being forged.
Further, it is possible to automatically control the excitation current according to the load of the drive mechanism and to supply the minimum excitation current. Therefore, the drive mechanism can be operated with a low torque margin without considering the torque margin expected in the conventional drive mechanism. When this driving means is applied to an exposure apparatus, thermal deformation of the exposure apparatus can be reduced, so that highly accurate position detection can be performed.

  According to the exposure apparatus of the above-described embodiment, since the trouble and life of the drive mechanism can be monitored from the outside without opening the purge atmosphere and the chamber atmosphere, the re-purge time and the purge opening work can be reduced, and the operation of the apparatus It is beneficial. Further, since the opening of the purge atmosphere is reduced, the chance that the optical system element in the purge atmosphere comes into contact with the air is reduced. As a result, the optical element is less likely to come into contact with harmful gases in the atmosphere, and contamination of the optical element can be reduced.

When the driving device according to the above-described embodiment is applied to an immersion exposure apparatus, the liquid is discarded in the motor driving unit configured in the liquid immersion region or the motor driving unit configured in the casing in contact with the liquid immersion region. It is possible to grasp the state of the motor drive unit without performing the above. Due to this effect, the discharge and insertion of liquid is reduced, and there is an advantage in operating the apparatus.
When the driving device according to the above-described embodiment is applied to an EUV exposure apparatus, the motor driving unit configured in the vacuum region or the motor driving unit configured in the housing in contact with the vacuum region does not open the vacuum region and is driven by the motor. It is possible to grasp the state of the part. Due to this effect, the number of times of vacuum purging is reduced, and there is an advantage in operating the apparatus.

  In the drive device according to the above-described embodiment, the excitation current value can be varied according to the load of the drive mechanism, so that a torque margin that allows for a difference in supply current value during installation and adjustment in the manufacturing process as in the conventional device. Do not need. Therefore, it is possible to operate the drive mechanism with an excitation current lower than that of the conventional device. Therefore, when the drive mechanism according to the above-described embodiment is applied to the position detection means, the heat generation amount of the drive mechanism is reduced by setting the excitation current of the drive mechanism near the necessary torque of the drive mechanism, and the position detection means Thermal effects can be reduced.

  The drive device according to the above-described embodiment or the position detection means using the drive device is suitable when it is disposed in a purge space such as an exposure device. For example, according to the exposure apparatus to which the drive apparatus according to the above-described embodiment is applied, the drive apparatus that can reduce the thermal variation factor of the apparatus is configured, and therefore, highly accurate position detection can be performed. Further, by monitoring the excitation current, it is possible to determine the maintenance timing of the drive mechanism and the malfunction without opening the purge space.

[Example of device manufacturing method]
Next, an embodiment of a device manufacturing method using the above-described exposure apparatus will be described with reference to FIGS. FIG. 4 is a flowchart for explaining how to fabricate devices (ie, semiconductor chips such as IC and LSI, LCDs, CCDs, and the like). Here, a semiconductor chip manufacturing method will be described as an example.
In step S1 (circuit design), a semiconductor device circuit is designed. In step S2 (mask fabrication), a mask is fabricated based on the designed circuit pattern. In step S3 (wafer manufacture), a wafer is manufactured using a material such as silicon. Step S4 (wafer process) is referred to as a pre-process, and an actual circuit is formed on the wafer using the mask and the wafer by the above exposure apparatus using the lithography technique. Step S5 (assembly) is called a post-process, and is a process for forming a semiconductor chip using the wafer manufactured in step S4. It includes assembly processes such as assembly process (dicing, bonding), packaging process (chip encapsulation) and the like. In step S6 (inspection), inspections such as an operation check test and a durability test of the semiconductor device manufactured in step S5 are performed. Through these steps, the semiconductor device is completed and shipped (step S7).

  FIG. 5 is a detailed flowchart of the wafer process in Step 4. In step S11 (oxidation), the surface of the wafer is oxidized. In step S12 (CVD), an insulating film is formed on the surface of the wafer. In step S14 (ion implantation), ions are implanted into the wafer. In step S15 (resist process), a photosensitive agent is applied to the wafer. In step S16 (exposure), the circuit pattern of the mask is exposed on the wafer by the exposure apparatus. In step S17 (development), the exposed wafer is developed. In step S18 (etching), portions other than the developed resist image are removed. In step S19 (resist stripping), the resist that has become unnecessary after the etching is removed. By repeatedly performing these steps, multiple circuit patterns are formed on the wafer.

It is a figure which shows schematic structure of the exposure apparatus which concerns on one Example of this invention. It is explanatory drawing for demonstrating the effect | action and effect of Example 1 of this invention. It is explanatory drawing for demonstrating the effect | action and effect of Example 2 of this invention. It is a flowchart for demonstrating manufacture of the device using the exposure apparatus which concerns on this invention. 5 is a detailed flowchart of the wafer process in Step 4 of the flowchart shown in FIG. 4.

Explanation of symbols

1: Original plate 2: Original plate stage 3: Reference original plate 4: Substrate (wafer)
5: Reference substrate 6: Substrate stage 7: Projection optical system 8: Laser interferometer 9: Moving mirror 10: Light source unit 11: Propagation lens 12: Propagation lens 13: Beam shaping optical system 14: Light quantity adjustment system 15: First position Detection means 15a: first detection system 15b: second detection system 15c: third detection system 16: switching mirror 17: first position detection means propagation lens 18: condenser lens 19: light integrator 20: mirror 21: condenser lens 22: Illumination method switching means 23: Masking blade 24: Masking imaging system 25: Collimator lens 26: Second position detection means 27: Third position detection means 28: Off-axis microscope

Claims (14)

A drive mechanism having a motor and current supply means for supplying an excitation current to the excitation winding of the motor;
Means for detecting excitation current of the motor or supply current to the drive mechanism;
Means for determining whether or not the detected current exceeds a first predetermined value and a second predetermined value larger than the first predetermined value, respectively. A drive mechanism having a motor and current supply means for supplying an excitation current to the excitation winding of the motor;
Means for detecting excitation current of the motor or supply current to the drive mechanism;
Means for setting an exciting current value or a limit value to be energized to the motor;
And means for controlling the excitation current supplied to the motor from the current supply means to coincide with the excitation current conduction value set in the setting means or to limit the excitation current limit value to the excitation current limit value. Drive device.   The energization amount control by the control means is released or an energization value sufficiently larger than the normal energization amount is given to the control means in place of the set excitation current energization value or limit value, and then detected by the detection means 3. The driving apparatus according to claim 2, further comprising means for determining whether or not the measured current has exceeded a first predetermined value and a second predetermined value larger than the first predetermined value.   4. The apparatus according to claim 1, further comprising means for warning that the maintenance timing of the drive mechanism has arrived when the excitation current of the motor or the current supplied to the drive mechanism exceeds the first predetermined value. The drive device described.   5. The apparatus according to claim 1, further comprising means for warning a malfunction of the drive mechanism when an excitation current of the motor or a supply current to the drive mechanism exceeds the second predetermined value. The drive device described.   The apparatus further comprises means for stopping the drive mechanism or a device equipped with the drive mechanism when an excitation current of the motor or a supply current to the drive mechanism exceeds the second predetermined value. The drive device according to 1, 3, 4 or 5.   2. The motor according to claim 1, wherein each of the motors has a plurality of excitation windings, and the current supply means includes the same number of current supply circuits as the excitation windings for supplying current to each excitation winding independently. The drive apparatus as described in any one of -6.   The drive device according to claim 1, wherein the drive mechanism is disposed in a purge space. A drive method of a drive mechanism having a motor and current supply means for supplying an excitation current to the excitation winding of the motor,
Providing a means for detecting in advance the excitation current of the motor or the supply current to the drive mechanism;
Measuring the excitation current of the motor or the supply current to the drive mechanism using the detection means;
A step of determining that the maintenance time of the drive mechanism has arrived when the measured current exceeds a first predetermined value;
And a step of determining that the drive mechanism has malfunctioned when a second predetermined value larger than the first predetermined value is exceeded. A drive method of a drive mechanism having a motor and current supply means for supplying an excitation current to the excitation winding of the motor,
Providing a means for detecting in advance the excitation current of the motor or the supply current to the drive mechanism;
The excitation current capable of generating the required torque of the drive mechanism is measured or estimated, and the excitation current energized from the current supply means to the motor or the limit value thereof is considered in consideration of a predetermined safety factor. A step of determining;
Measuring the excitation current of the motor or the supply current to the drive mechanism using the detection means;
And a step of controlling the excitation current energized from the current supply means to the motor or its limit value to coincide with the excitation current energization value determined in the determination step or to limit to the excitation current limit value. A driving method characterized by the above. The excitation current energized from the current supply means to the motor or a limit value thereof is set to a value sufficiently larger than that during normal operation, or the control of the energization amount is released, and then the motor is detected using the detection means. A step of measuring the amount of exciting current energized or the amount of current supplied to the drive mechanism;
A step of determining that the maintenance time of the drive mechanism has arrived when the measured current exceeds a first predetermined value;
The driving method according to claim 10, further comprising a step of determining that the driving mechanism has failed when a second predetermined value larger than the first predetermined value is exceeded.   A position detecting device using the driving device according to claim 1 as at least one of driving devices for driving the movable part.   An exposure apparatus using the drive device according to any one of claims 1 to 8 as at least one drive device for driving the movable portion.   14. A device manufacturing method comprising: exposing a wafer using the exposure apparatus according to claim 13; and developing the wafer.

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