JP2009188013A - Aligner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aligner that can be miniaturized and can perform maskless exposure by stable operation. <P>SOLUTION: The aligner 10 includes: a light source 12; an MEMS optical scanner for inclining mirrors M1, M2 repeatedly; and an exposure optical system for exposing an object to be exposed to light to light from the light source via the mirrors. Light from the light source is applied to the object to be exposed to light by two-dimensional scanning for scanning in two directions on the object to be exposed to light by the mirrors inclined using the MEMS optical scanner. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an exposure apparatus capable of maskless exposure.

  Conventionally, a photolithography process is frequently used for forming a circuit pattern in a manufacturing process of a semiconductor integrated circuit or a liquid crystal device. Photolithography uses a photomask on which a predetermined pattern is formed, and the photomask pattern is transferred onto the substrate by exposing it onto a substrate such as silicon coated with a photoresist through the photomask. Then, a pattern is formed on the substrate through a development process, an etching process, and the like.

  A maskless exposure (direct exposure) apparatus that directly forms a desired pattern on a substrate or the like without using a photomask instead of the photolithography process as described above has been proposed (for example, see Patent Document 1 below). According to such maskless exposure, a photomask is unnecessary, which is advantageous in terms of cost, and high-precision exposure is possible.

The maskless exposure apparatus described in Patent Document 1 includes a scanning unit that relatively scans a desired exposure pattern imaged by an imaging optical system of an exposure head and the surface of an object to be exposed. An XY stage is used. As an optical scanning means, an optical scanning optical system using a polygon mirror, a galvanometer mirror and a lens optical system is known. In addition, it has been proposed to use a two-dimensional light modulation element instead of the optical scanning optical system (for example, see Patent Document 2 below).
JP 2006-259882 A JP 2003-15077 A

  If an optical scanning optical system using a polygon mirror or a galvano mirror and a lens optical system is used as the above optical scanning means, the overall configuration of the apparatus becomes large, which is an obstacle to miniaturization of the apparatus, and is expensive. Responsiveness is not good. In addition, it is said that the two-dimensional light modulation element has a problem of shortening the life and occurrence of malfunction, and a special configuration and cost are required for countermeasure against malfunction (see Patent Document 1), which is not preferable.

  An object of the present invention is to provide an exposure apparatus that can be reduced in size and can perform maskless exposure with a stable operation in view of the above-described problems of the prior art.

  In order to achieve the above object, the exposure apparatus according to the present embodiment includes a light source, a MEMS optical scanner that repeatedly tilts a mirror, and exposure optics that exposes light from the light source onto the object to be exposed via the mirror. And irradiating the object to be exposed by two-dimensional scanning so that light from the light source is scanned in two directions on the object to be exposed by a mirror inclined by the MEMS optical scanner. The object to be exposed is exposed.

  According to this exposure apparatus, a mirror is repeatedly tilted by a MEMS light scanner, light from a light source is scanned to obtain scanning light, and the object to be exposed can be directly exposed. MEMS (abbreviation) is an abbreviation for micro electro mechanical systems, and is a small device in which mechanical component parts are manufactured in a minimum size. The MEMS optical scanner is a MEMS optical device that scans light by driving a mirror by an actuator, and is configured to be small in size and highly reliable and stable in operation. As described above, by using the MEMS optical scanner for optical scanning, it is possible to reduce the size of the apparatus and realize an exposure apparatus capable of maskless exposure with stable operation.

  Further, by scanning the light from the light source two-dimensionally with a mirror that repeatedly tilts with a MEMS optical scanner, scanning light in two different directions can be obtained, and the object to be exposed can be exposed in two different directions.

  In the above exposure apparatus, the MEMS optical scanner can be configured to scan light one-dimensionally and to be arranged two in the exposure optical system to scan light two-dimensionally. The MEMS optical scanner can be configured to scan light two-dimensionally as a single unit.

  In addition, a stage that can be moved by placing the object to be exposed is provided, and a pattern is exposed on the object to be exposed by controlling the movement of the stage, so that a desired pattern is directly formed on the object to be exposed. Can be exposed.

  A stage detection unit that detects the position of the stage; the stage includes a motor as a drive source; and the stage is controlled by driving the motor based on a detection signal of the position detection unit. Feedback control can be performed to control the position of the stage with high accuracy.

  Further, by controlling the on / off of light from the light source to expose a pattern on the object to be exposed, for example, an intermittent pattern in the scanning direction or an intermittent pattern in a direction perpendicular to the scanning direction, etc. A desired pattern can be exposed.

  In addition, the exposure optical system includes an objective lens, and is provided with an autofocus mechanism that automatically focuses the objective lens with respect to the object to be exposed, so that it can be automatically focused during exposure. Therefore, high-precision exposure is possible even if the surface of the object to be exposed has irregularities.

  According to the exposure apparatus of the present invention, maskless exposure can be performed by scanning light that can be reduced in size and scans in two directions with stable operation.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

<First Embodiment>
FIG. 1 is a view showing the schematic arrangement of the entire exposure apparatus according to the first embodiment. FIG. 2 is a view for explaining the exposure optical system of FIG. 3 is a top view of a part of the exposure optical system in FIG. 2 (range III surrounded by a broken line in FIG. 2).

  As shown in FIG. 1, the exposure apparatus 10 includes an XY stage 11 on which an object to be exposed A is placed, held, and movable in the XY directions, a light source 12 composed of a semiconductor laser, and a light source 12 guided by an optical fiber FI. An exposure optical system that exposes the exposure object A with the emitted light, and an objective lens in the lens barrel 31 of the exposure optical system when performing exposure in the vertical direction of the drawing with respect to the exposure object A on the XY stage 11 An autofocus mechanism for driving and automatically focusing, an observation optical system for observing the exposure object A on the XY stage 11, and a control device 13 for controlling the XY stage 11 and the light source 12 are provided. .

  In the exposure optical system, as shown in FIGS. 1 to 3, light from the light source 12 is introduced through an optical fiber FI, collimated by a collimating lens C, reflected by a mirror M2, and passed through lenses L4 and L3. Reflected by the mirror M1, focused on the surface A1 of the exposure object A on the stage 11 by the objective lens J in the lens barrel 31 through the lens L2, the mirror 19, the lens L1, and the beam splitter 29 to form an image. It comes to irradiate.

  Each optical element from the collimating lens C to the lens L1 in the exposure optical system described above is disposed and accommodated in the housing 20.

  As shown in FIG. 1, the autofocus mechanism is configured such that the light from the autofocus laser light source 22 passes through the beam splitters 27, 28, and 29 and the objective lens J (FIG. 2) in the lens barrel 31 covers the XY stage 11. The light is condensed on the surface A1 of the exposure object A, and the reflected light enters the light receiving element 21 including a photodiode (PD) through the objective lens J, the beam splitters 29, 28, and 27, the tube lens 32, and the beam splitter 26. Based on the incident light signal, the lens barrel 31 is driven in the optical axis direction by an actuator 23 made of a known piezo element, and the objective lens J (FIG. 2) in the lens barrel 31 is moved to focus. ing.

  The above-described beam splitters 26, 27, 28, 29 and the tube lens 32 are disposed and accommodated in the housing 30.

  The observation optical system can observe the object A by introducing illumination light from the light introducing unit 25 and irradiating the object A on the XY stage 11 and imaging the reflected light with the CCD camera 24. ing.

  As shown in FIG. 1, a light receiving element 21, an autofocus laser light source 22, a CCD camera 24, and a light introducing portion 25 are attached to the housing 30, and an actuator 23 is disposed at the lower end of the housing 30. A lens barrel 31 is disposed below the lens.

  The XY stage 11 includes a linear motion mechanism composed of a known ball screw or the like that converts the rotary motions of the stepping motors 15a and 15b and the stepping motors 15a and 15b of FIG. 1 into linear motions in the X and Y directions. Is built-in. The XY stage 11 can be moved at a constant speed in the horizontal direction (X direction) in FIG. 1 and in the vertical direction (Y direction) in FIG. 1 by the constant speed rotations of the stepping motors 15a and 15b.

  The control device 13 controls the stepping motors 15 a and 15 b via the motor driver 16. In addition, the exposure apparatus 10 includes a position detection unit 14 including an encoder that detects each position of the XY stage 11 in the X direction and the Y direction.

  The control device 13 controls the movement amounts of the XY stage 11 in the X direction and the Y direction. At this time, feedback control is performed on the stepping motors 15a and 15b based on the position detection signal input from the position detection unit 14. The XY stage 11 can be controlled with high accuracy.

  In addition, the control device 13 performs on / off control of the light source 12 via the driver 17 to turn on / off light from the light source 12. Note that a known electric shutter may be placed after the light source 12 and the electric shutter may be controlled by the control device 13 to turn on and off the light from the light source 12.

  Further, the control device 13 includes a CPU (Central Processing Unit), and the CPU controls the light source 12 and the XY stage 11 in a predetermined sequence so that exposure of a predetermined pattern is possible.

  The mirrors M1 and M2 shown in FIGS. 1 to 3 constitute a part of the MEMS optical scanner. The MEMS optical scanner will be described with reference to FIGS.

  FIG. 4 is a schematic diagram for explaining the basic structure and operation principle of a MEMS optical scanner that can be used in the exposure apparatus of FIGS. FIG. 5 is a top view (a) showing a specific example of a MEMS optical scanner that can be used in the exposure apparatus of FIGS. 1 to 3, a cross-sectional view (b), and a bottom view (c) cut in the bb line direction. .

  In the MEMS optical scanner shown in FIG. 4, a rectangular planar mirror M is formed in a rectangular yoke Y so as to be connected to the yoke Y by a pair of torsion bars T, T, and a drive coil is formed along the outer periphery of the mirror M. D is formed, and a pair of permanent magnets P1 and P2 is disposed so as to face the outside of the yoke Y, and is an electromagnetically driven resonance type in which a mirror is driven by an electromagnetically driven actuator.

  In the MEMS optical scanner, as shown in FIG. 4, when a magnetic field having a magnetic flux density B is generated in a direction perpendicular to the torsion bars T and T by the permanent magnets P1 and P2 and a current i is supplied to the drive coil D, rotation by Lorentz force F occurs. The torsion bars T and T are rotated against the elastic restoring force by torque, and the mirror M is tilted. By making the current i an alternating current, the torsion bars T and T resonate and rotate in the rotation direction r and the opposite direction r ′, so that the mirror M resonates and repeats the inclination. Since F∝i · B, the inclination of the mirror M can be changed by changing the amount of current. Since the mirror M is inclined in the rotational directions r and r 'and changes the direction of light incident on the mirror M and reflected in one direction, the MEMS optical scanner in FIG. 4 is a one-dimensional movable type.

  Specifically, as shown in FIGS. 5A to 5C, the MEMS optical scanner 1 is provided with a yoke 4 on the reference surface 6 a side of the substrate 6, and with the permanent magnets 2 and 3 facing the inside of the yoke 4. The silicon chip 7 is provided between the permanent magnets 2 and 3, the mirror 5 is disposed so as to be surrounded by the silicon chip 7, a drive coil is formed as shown in FIG. As shown in FIGS. 5B and 5C, the mirror 5 resonates in the rotation direction r around the rotation center axis p and in the opposite direction r ′ as shown in FIGS. This is repeated, and is configured as a one-dimensional movable type electromagnetically driven resonance type.

  In the MEMS optical scanner 1 shown in FIGS. 5A to 5C, when the incident light n is reflected by the mirror M on the opposite surface 6b side of the reference surface 6a of the substrate 6, the reflected light n ′ is reflected from the reference surface 6a. The angle changes according to the tilt angle of the mirror 5. The MEMS optical scanner 1 is provided with a torsion bar similar to the torsion bar T in FIG. 4 on the rotation center axis p.

  The MEMS optical scanner 1 shown in FIGS. 5A to 5C has minute components, and the overall dimensions thereof are, for example, 30 mm × 22 mm × 5 mm (thickness). Is 4 mm × 4 mm. Such a MEMS optical scanner is sold, for example, by Nippon Signal Co., Ltd. under the trade name “ECO SCAN: ESS115B”.

  The two MEMS optical scanners 1 are arranged at the positions of the mirrors M1 and M2 in FIGS. 1 to 3, respectively, so that the scanning lights by the mirrors M1 and M2 are reflected in directions orthogonal to each other. That is, the MEMS optical scanner 1 has mounting holes 6c at the four corners of the substrate 6, and the mirrors 5 are mirrors at two predetermined positions in the housing 20 of the exposure apparatus 10 in FIG. 1 with reference to the reference surface 6a. It attaches with the attachment hole 6c so that the function of M1 and M2 may be exhibited. Each MEMS optical scanner 1 is controlled by a control device 13 as shown in FIG.

  Next, the exposure operation of the exposure apparatus 10 in FIGS. 1 to 3 will be described with reference to FIGS. FIG. 6 is a schematic diagram for explaining an example of a pattern exposed on the surface of the object to be exposed in FIG.

  First, exposure by the exposure apparatus 10 will be described. First, light from the light source 12 is converted into parallel light m by the collimator lens C and enters the mirror M2 as shown in FIG. The mirror M2 corresponds to the mirror 5 of the MEMS optical scanner 1 shown in FIGS. 5A to 5C. By passing an alternating current through the MEMS optical scanner 1 like the drive coil D shown in FIG. 4, the mirror shown in FIG. The rotation is repeated around the rotation axis 18 (corresponding to the torsion bar T in FIG. 4 and coaxial with the rotation center axis p in FIG. 5), and is inclined at an inclination angle β2 with respect to the optical axis a as shown in FIG. .

  Next, the light reflected by the mirror M2 becomes parallel light through the lens L4 having the focal length f4 and the lens L3 having the focal length f3, and enters the mirror M1. The mirror M1 corresponds to the mirror 5 of the MEMS optical scanner 1 like the mirror M2, and corresponds to the torsion bar T of FIG. 4 by passing an alternating current through the MEMS optical scanner 1 like the drive coil D of FIG. The rotation is repeated around the mirror rotation axis (extending in the direction perpendicular to the paper surface of FIG. 2), and the optical axis b is inclined at an inclination angle α2 as shown in FIG.

  Next, the light reflected by the mirror M1 is passed through the lens L2, the mirror 19 (FIG. 1) having the focal length f2, the lens L1 having the focal length f1, and the objective lens J having the focal length f0 via the beam splitter 29 (FIG. 1). It is focused on the surface A1 of the object A to be exposed in FIG.

By the MEMS optical scanner 1, the mirror M1 scans the light from the light source in the horizontal direction (X direction) of FIGS. 1, 2, and 6 to obtain the first scanning light. The scanning length x0 of the first scanning light in the X direction from the optical axis c (FIG. 2) on the surface A1 can be expressed by the following equation (1).
x0 = f0 · (f2 / f1) · tan (α2) (1)
Where α2: tilt angle (deflection angle) in the X direction with respect to the optical axis b of the mirror M1

Further, the mirror M2 scans the light from the light source 12 in the direction perpendicular to the plane of FIG. 1 and FIG. 2 (Y direction in FIG. 6) by the MEMS optical scanner 1 to obtain the second scanning light. The scanning length y0 of the second scanning light in the Y direction from the optical axis c on the surface A1 can be expressed by the following equation (2).
y0 = f0 · (f2 / f1) · (f4 / f3) · tan (β2) (2)
Where β2: tilt angle (deflection angle) in the Y direction with respect to the optical axis a of the mirror M2

  As described above, with respect to the surface A1 of the exposure object A placed and held on the XY stage 11 of FIG. 1, light from the light source 12 is reflected in two directions orthogonal to each other in the XY directions by the mirrors M1 and M2. By scanning, the first scanning light and the second scanning light can be irradiated and exposed. At this time, for example, patterns PA and PA1 as shown in FIG. 6 can be exposed as follows.

  The object A is placed and held on the XY stage 11 in FIG. 1, the XY stage 11 is moved to a predetermined position, the light source 12 is turned on, the MEMS optical scanner 1 is driven, and the mirrors M1 and M2 are vibrated. Then, the light from the light source 12 is scanned on the surface A1 of the exposure object A with the scanning length x0 in the X direction and the second scanning light in the Y direction as shown in FIG. Scanning is performed with the scanning length y0, and the surface A1 can be exposed with the substantially circular or substantially elliptical small pattern PA as shown in FIG. 6 by the first and second scanning lights.

  Next, for example, when the stepping motor 15b of the XY stage 11 is driven, the XY stage 11 moves at a constant speed in the Y direction and corresponds to the scanning length x0 on the surface A1 of the exposure object A by being driven for a predetermined time. The elongated pattern PA1 indicated by a broken line having a predetermined width and a predetermined length can be exposed.

  As described above, it is possible to expose a pattern having a relatively wide predetermined width. Further, an intermittent pattern can be formed by turning off the light source 12 while the XY stage 11 is moving at a constant speed in the Y direction.

  When the autofocus mechanism shown in FIG. 1 is activated during the exposure, the light from the laser light source 22 is condensed on the surface A1 of the exposure object A via the objective lens J (FIG. 2), and the reflected light thereof. Enters the light receiving element 21, and the actuator 23 drives the objective lens J in the lens barrel 31 in the direction of the optical axis based on the incident light signal to automatically focus. The autofocus mechanism is continuously operated during exposure with light from the light source 12, so that exposure can be performed with high accuracy even if the surface A1 of the object A to be exposed is uneven. Further, the surface A1 of the exposure object A is observed with the CCD camera 24 as necessary.

  As described above, the MEMS optical scanner is a MEMS optical device that scans light by resonating a mirror by an electromagnetically driven actuator, and is configured in a small size and has high reliability and stable operation. By using the scanner for optical scanning of the exposure apparatus 10, it is possible to reduce the size of the apparatus and realize an exposure apparatus capable of maskless exposure with stable operation.

  According to the conventional optical scanning optical scanning optical system using a polygon mirror or galvano mirror and a lens optical system, the overall configuration of the apparatus is large, expensive, and responsive. By using the MEMS optical scanner as in the above embodiment, it is possible to reduce the size and size of the exposure apparatus 10, and to perform optical scanning of the exposure apparatus 10 with good response, and further save power compared to the conventional configuration. In addition, the conventional two-dimensional light modulation element, which is another optical scanning means, has a problem of shortening the lifetime and occurrence of malfunction, but by using a MEMS optical scanner, reliable and stable exposure is possible. It becomes.

  Further, by scanning the light from the light source 12 with the mirrors M1 and M2 that are vibrated by the MEMS optical scanner 1, the first scanning light and the second scanning light that respectively scan in the two directions orthogonal to each other on the exposure object A are obtained. Obtainable. Such two-dimensional exposure allows exposure with a predetermined scanning length in two directions.

<Second Embodiment>
FIG. 7 is a view showing the schematic arrangement of the entire exposure apparatus according to the second embodiment. FIG. 8 is a view for explaining the exposure optical system of FIG. FIG. 9 is a diagram schematically showing the relationship between the mirror and the lens of the exposure optical system in FIG.

  The exposure apparatus 50 shown in FIG. 7 has the same configuration as the exposure apparatus 10 of FIG. 1 except that the MEMS optical scanner of the mirror M3 of the exposure optical system is a two-dimensional movable type. The description is omitted.

  As shown in FIGS. 7 to 9, the exposure optical system of the exposure apparatus 50 has the light from the light source 12 introduced through the optical fiber FI, collimated by the collimator lens C, reflected by the mirror M3, and the lenses L2, L2 The light is condensed and focused on the surface A1 of the object A on the stage 11 by the objective lens J in the lens barrel 31 via the mirror 19, the lens L1, and the beam splitter 29.

  FIG. 10 is a schematic diagram for explaining the basic structure and operation principle of a two-dimensional movable type MEMS optical scanner that can be used in the exposure apparatus of FIGS. FIG. 11 is a top view (a) showing a specific example of a two-dimensional movable type MEMS optical scanner that can be used in the exposure apparatus of FIGS. 7 to 9, a cross-sectional view (b) taken along line bb-bb, It is a bottom view (c).

  In the MEMS optical scanner shown in FIG. 10, a rectangular coil wiring portion H is formed in a rectangular yoke Y so as to be connected to the yoke Y by a pair of torsion bars T2 and T2, and the rectangular shape is formed in the coil wiring portion H. The planar mirror M is formed so as to be connected to the coil wiring part H by a pair of torsion bars T1 and T1, and the torsion bars T1 and T1 and the torsion bars T2 and T2 are arranged so as to be orthogonal to each other. Drive coils D1 and D2 are respectively formed from H to the outer periphery of the mirror M, and a pair of permanent magnets P1 and P2 and another pair of permanent magnets P3 and P4 are respectively arranged so as to face the outside of the yoke Y. There is an electromagnetically driven resonance type in which the mirror is driven by an electromagnetically driven actuator similar to FIG.

  As shown in FIG. 10, in the MEMS optical scanner, when a magnetic field having a magnetic flux density BA is generated in a direction perpendicular to the torsion bars T1 and T1 by the permanent magnets P1 and P2, and a current iA is passed through the drive coil D1, rotation by Lorentz force FA occurs. The torsion bars T1 and T1 rotate against the elastic restoring force by torque to tilt the mirror M in one direction, and the magnetic field of the magnetic flux density BB is orthogonal to the torsion bars T2 and T2 by the permanent magnets P3 and P4. When the current iB flows through the driving coil D2, the torsion bars T2 and T2 are rotated against the elastic restoring force by the rotational torque generated by the Lorentz force FB so that the mirror M is orthogonal to the one direction. T1, T1 tilts.

  By using the currents iA and iB as alternating currents, the torsion bars T1 and T1 resonate and rotate in the rotation direction r and the opposite direction r ′, and the torsion bars T2 and T2 rotate in the rotation direction s and the opposite direction s ′. , The mirror M resonates and repeats tilting in two directions. Since F∝i · B, the inclination of the mirror M can be changed by changing the amount of current. Since the mirror M is inclined in the rotation directions r, r 'and s, s', and changes the direction of light incident on the mirror M and reflected in two directions, the MEMS optical scanner in FIG. 10 is a two-dimensional movable type.

  Specifically, the MEMS optical scanner 9 has basically the same structure as that shown in FIGS. 5A to 5C as shown in FIGS. 11A to 11C, and the reference surface 6 a of the substrate 6. The yoke 4 is provided on the side, the permanent magnets 2A, 3A and the permanent magnets 2B, 3B are arranged facing each other inside the yoke 4, and the silicon chip 7 is arranged inside the permanent magnets 2A, 3A, the permanent magnets 2B, 3B. Then, the mirror 5 is arranged so as to be surrounded by the silicon chip 7, a drive coil is formed as shown in FIG. 10, and an alternating current is applied to each drive coil from the outside via the connector 8. As shown in FIG. 10, it resonates in two directions and repeats the inclination, and is configured as a two-dimensional movable type electromagnetically driven resonance type.

  In the MEMS optical scanner 9 of FIGS. 11A to 11C, when incident light is reflected by the mirror M on the opposite surface 6b side of the reference surface 6a of the substrate 6, the reflection angle of the reflected light with respect to the reference surface 6a is the mirror. It changes according to the inclination angle of 5. In the MEMS optical scanner 9, torsion bars similar to the torsion bars T2 and T1 in FIG. 10 are provided on the rotation center axis p and on the axis in the direction orthogonal thereto.

  Each of the MEMS optical scanner 9 in FIGS. 11A to 11C is configured with minute parts, and the overall dimensions thereof are, for example, 50 mm × 35 mm × 9 mm (thickness). Is 4 mm × 3 mm. Such a two-dimensional movable type MEMS optical scanner is sold, for example, by Nippon Signal Co., Ltd. under the trade name “ECO SCAN: ESS212B”.

  A MEMS optical scanner 9 is disposed at the position of the mirror M3 in FIGS. That is, the MEMS optical scanner 9 has mounting holes 6c at the four corners of the substrate 6, and the mirror 5 exhibits the function of the mirror M3 at a predetermined position in the housing 20 of the exposure apparatus 50 in FIG. 7 with reference to the reference surface 6a. It attaches with the attachment hole 6c so that it may do. Further, the MEMS optical scanner 9 is controlled by the control device 13 as shown in FIG.

  Next, exposure by the exposure apparatus 50 in FIGS. 7 to 9 will be further described. First, the light from the light source 12 is converted into parallel light m by the collimating lens C and enters the mirror M3 as shown in FIG. The mirror M3 corresponds to the mirror 5 of the MEMS optical scanner 9 in FIGS. 11A to 11C, and an alternating current is passed through the MEMS optical scanner 9 like the drive coils D1 and D2 in FIG. The rotation is repeated about the torsion rods T1 and T2 and the inclination is two-dimensionally repeated with respect to the optical axis b in FIG. That is, the mirror M3 is inclined at the inclination angle α2 in the X direction as shown in FIG. 9, and is inclined at the inclination angle γ2 in the Y direction orthogonal to the X direction.

Here, as shown in FIG. 9, with respect to the light m ′ reflected by the mirror M3 inclined in the X direction and the Y direction, the following equation is established between the mirror M3 and the lens L2.
tan (α2) = x2 / f2
tan (γ2) = y2 / f2

  Next, the light m ′ reflected by the mirror M3 passes through the lens L2, the mirror 19 (FIG. 7) having the focal length f2, the lens L1 having the focal length f1, and the objective lens having the focal length f0 via the beam splitter 29 (FIG. 7). The light is condensed by J on the surface A1 of the object A to be exposed in FIG.

The mirror M3 scans the parallel light m from the light source 12 in the X and Y directions in FIG. 9 by the MEMS optical scanner 9, and scans the first scanning light in the X direction from the optical axis c on the surface A1 in FIG. The length x0 can be expressed by the following formula (1), and similarly, the scanning length y0 of the second scanning light in the Y direction (the vertical direction in FIG. 8) can be expressed by the following formula (3). .
x0 = f0 · (f2 / f1) · tan (α2) (1)
y0 = f0 · (f2 / f1) · tan (γ2) (3)
Where α2: tilt angle (deflection angle) in the X direction with respect to the optical axis b of the mirror M3
γ2: inclination angle (deflection angle) in the Y direction with respect to the optical axis b of the mirror M3

  As described above, the light from the light source 12 is scanned by the mirror M3 in two directions orthogonal to each other in the XY direction on the surface A1 of the exposure object A placed and held on the XY stage 11 of FIG. Thus, the first scanning light and the second scanning light can be irradiated and exposed. Thereby, for example, patterns PA and PA1 as shown in FIG. 6 can be exposed by the same control as described above.

  As described above, the MEMS optical scanner 9 is a MEMS optical device that scans light by resonating the mirror 5 with an electromagnetic drive actuator, and is configured in a small size and has high reliability and stable operation. By using the MEMS optical scanner 9 for optical scanning of the exposure apparatus 50, it is possible to reduce the size of the apparatus and realize an exposure apparatus capable of maskless exposure with stable operation.

  According to the conventional optical scanning optical scanning optical system using a polygon mirror or galvano mirror and a lens optical system, the overall configuration of the apparatus is large, expensive, and responsive. By using the MEMS optical scanner as in the above embodiment, it is possible to reduce the size and size of the scanner, and to perform optical scanning of the exposure apparatus 50 with good response, and further saves power compared to the conventional configuration. In addition, the conventional two-dimensional light modulation element, which is another optical scanning means, has a problem of shortening the lifetime and occurrence of malfunction, but by using a MEMS optical scanner, reliable and stable exposure is possible. It becomes.

  Further, by scanning the light from the light source 12 by the mirror M3 that is vibrated by the MEMS optical scanner 9, the first scanning light and the second scanning light that respectively scan in the two directions orthogonal to each other on the exposure object A are obtained. Can do. Such two-dimensional exposure allows exposure with a predetermined scanning length in two directions.

  Further, in the exposure optical system of FIGS. 1 to 3, two two-dimensional movable type MEMS optical scanners 1 are used and two mirrors M1 and M2 are arranged, whereas according to the exposure optical system of FIGS. For example, by using a two-dimensional movable type MEMS optical scanner, it is only necessary to arrange one mirror M3, and the mirror M2, lenses L3 and L4 in FIGS. 1 to 3 can be omitted, so that the configuration of the exposure optical system is simplified. Can be

  In each of the above embodiments, with respect to the pattern that can be exposed, by controlling on / off of light from the light source 12 and movement of the XY stage 11, an arbitrary pattern is formed on the surface A1 of the object A by the light from the light source 12. Can be exposed. For example, the control device 13 causes the CPU to read a program for exposing with a desired pattern from a storage device such as an internal or external hard disk storage device, and controls the light source 12 and the XY stage 11 according to the program to perform exposure. The apparatuses 10 and 50 can perform automatic exposure with a desired pattern.

  As described above, the best mode for carrying out the present invention has been described. However, the present invention is not limited to these, and various modifications are possible within the scope of the technical idea of the present invention. For example, the scanning length x0 in the X direction and the scanning length y0 in the Y direction of the scanning light on the surface A1 of the exposure object A are the drive currents to the MEMS optical scanners 1 and 9 of the mirrors M1, M2 and M3, respectively. By changing the mirror angle, the mirror tilt angle can be changed and can be adjusted within a predetermined range.

  The exposure apparatus 10 of FIG. 1 can also perform one-dimensional exposure with scanning light that scans in one direction (X direction or Y direction) by driving only one of the mirrors M1 and M2. Similarly, the exposure apparatus 50 in FIG. 7 performs one-dimensional exposure with scanning light that scans in one direction (X direction or Y direction) by passing a current through only one of the drive coils D1 or D2 in FIG. It can also be done.

  In addition, the MEMS optical scanners 1 and 9 are configured as a resonance type that is displaced by an alternating current, but may be a MEMS optical scanner that is displaced by a direct current.

  Further, the shape of the small pattern PA of FIG. 6 by two-dimensional exposure can be made circular, elliptical, or linear by appropriately setting the vibration periods and phases of the mirrors M1, M2, and M3, for example. Further, the shape of the small pattern PA can be made linear by the one-dimensional exposure.

It is a figure which shows the schematic structure of the whole exposure apparatus by 1st Embodiment. It is a figure for demonstrating the exposure optical system of FIG. FIG. 3 is a top view of a part of the exposure optical system in FIG. 2 (range III surrounded by a broken line in FIG. 2). FIG. 4 is a schematic diagram for explaining the basic structure and operation principle of a MEMS optical scanner that can be used in the exposure apparatus of FIGS. FIG. 4 is a top view (a) showing a specific example of a MEMS optical scanner that can be used in the exposure apparatus of FIGS. 1 to 3, a cross-sectional view (b), and a bottom view (c) taken along line bb. It is a schematic diagram for demonstrating an example of the pattern exposed on the surface of the to-be-exposed thing of FIG. It is a figure which shows the schematic structure of the whole exposure apparatus by 2nd Embodiment. It is a figure for demonstrating the exposure optical system of FIG. FIG. 9 is a diagram schematically illustrating a relationship between a mirror and a lens in the exposure optical system in FIG. 8. FIG. 10 is a schematic diagram for explaining the basic structure and operation principle of a two-dimensional movable type MEMS optical scanner that can be used in the exposure apparatus of FIGS. 7 to 9. A top view (a) showing a specific example of a two-dimensional movable type MEMS optical scanner that can be used in the exposure apparatus of FIGS. 7 to 9, a cross-sectional view (b) and a bottom view taken along line bb-bb ( c).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,9 MEMS optical scanner 5 Mirror 10,50 Exposure apparatus 11 XY stage 12 Light source 13 Control apparatus 14 Position detection part 15a, 15b Stepping motor 21 Light receiving element 22 Laser light source for autofocus 23 Actuator 24 CCD camera 25 Light introduction part 26- 29 Beam splitter 20, 30 Housing 31 Lens barrel 32 Tube lens A Object to be exposed A1 Surface B, BA, BB Magnetic flux density C Collimator lens D, D1, D2 Drive coil F, FA, FB Lorentz force FI Optical fiber H Coil wiring part J Objective lens L1-L4 Lens M Mirror M1, M2, M3 Mirror P1, P2 Permanent magnet P3, P4 Permanent magnet PA, PA1 Pattern T, T2, T1 Torsion bar Y Yoke a Optical axis b Optical axis c Optical axis f0 Focal length f1 Focal length f2 the focal length f3 the focal length f4 the focal length i, iA, iB current m parallel light m 'reflected n incident light n reflected light p rotation axis r, s rotation direction r', s' rotation direction r, reverse s

Claims (7)

A light source, a MEMS optical scanner that repeatedly tilts a mirror, and an exposure optical system that exposes light from the light source onto the object to be exposed through the mirror,
Two-dimensional scanning is performed so that light from the light source is scanned in two directions on the object by a mirror inclined by the MEMS optical scanner, and the object to be exposed is irradiated onto the object to be exposed. An exposure device for exposure.   The exposure apparatus according to claim 1, wherein the MEMS optical scanner scans light in a one-dimensional manner, and is arranged in the exposure optical system to scan light in a two-dimensional manner.   The exposure apparatus according to claim 1, wherein the MEMS optical scanner alone scans light two-dimensionally. Comprising a stage on which the object to be exposed is movable;
The exposure apparatus according to any one of claims 1 to 3, wherein a predetermined pattern is exposed on the object to be exposed by controlling movement of the stage. A position detector for detecting the position of the stage;
The stage has a motor as a drive source,
The exposure apparatus according to claim 4, wherein the motor is driven to control the position of the stage based on a detection signal of the position detection unit.   The exposure apparatus according to any one of claims 1 to 5, wherein a pattern is exposed on the object to be exposed by controlling on / off of light from the light source. The exposure optical system includes an objective lens;
The exposure apparatus according to any one of claims 1 to 6, further comprising an autofocus mechanism that drives the objective lens to the object to be exposed and automatically focuses the object.

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