JP3209936U - Frustrated cube assembly - Google Patents

Abstract

A frustrated cube assembly capable of accurately and cost-effectively creating a pattern on a substrate is provided. A first prism 402 including a first surface 406, a second surface 408, and a first inclined surface 410, a third surface 412, a fourth surface 414, and a second inclined surface. The first and second slopes face each other and are separated by an air gap 420. Further, it includes an inclined mirror 418 adjacent to the second surface. The second surface can be a reflective diffraction grating. The light beam 273 enters the frustrated cube assembly at normal incidence, reflects and travels to an adjacent digital micromirror device (DMD) 280, exits the image projection system along a single optical axis, and finally Projected onto the substrate. The input light beam and the output light beam are parallel. [Selection] Figure 4

Description

(Technical field)
Embodiments of the present disclosure generally relate to an apparatus and system for processing one or more substrates, and more specifically to an apparatus for performing a photolithography process.

(Description of related technology)
Photolithography is widely used in the manufacture of semiconductor devices and display devices (eg, liquid crystal displays (LCDs)). Large area substrates are often used in the manufacture of LCDs. LCDs or flat panels are commonly used for active matrix displays (eg, computers, touch panel devices, personal digital assistants (PDAs), cell phones, television monitors, etc.). In general, a flat panel can include a layer of liquid crystal material that forms a pixel sandwiched between two plates. When power from the power source is applied to the liquid crystal material, the amount of light passing through the liquid crystal material can be controlled at pixel locations that allow an image to be generated.

  Microlithography techniques are generally used to create an electrical structure that is incorporated as part of the liquid crystal material layer that forms the pixel. According to these techniques, a photosensitive photoresist is typically applied to at least one surface of the substrate. A pattern generator is then exposed by light to expose selected areas of the photosensitive photoresist as part of the pattern, causing a chemical change in the photoresist in the selected areas and creating a mask, or Preparing these selected areas for subsequent development to remove any unexposed areas of the photoresist and masks from the etching process used to pattern the underlying layer and form the electrical structure. Resist or protect the underlying layer portion.

  New devices and approaches are needed to accurately and cost-effectively create patterns on substrates (eg, large area substrates) to continue to provide consumers with display devices and other devices at prices required by consumers It is said that.

  The present disclosure is generally a first prism, a first prism including a first surface, a second surface, and a first slope (hypotenuse), and a second prism, A frustrated cube assembly having a third surface, a fourth surface, and a second prism including a second inclined surface (total leakage light is internally lost by using leaky total reflection to minimize energy) Cube-shaped optical element assembly having a function of filtering light so as to cause loss. The first and second slopes face each other and are separated by an air gap. The frustrated cube assembly can include an inclined mirror adjacent to the second surface. The second surface can be a reflective diffraction grating. Light is reflected through the image projection system along a single optical axis to a digital micromirror device (DMD) adjacent to the frustrated cube assembly at normal incidence. The direction of light incident on the DMD is such that the light reflected from the “on” mirror is directed at 45 degrees to the slope along the normal of the DMD surface. The input light beam and the output light beam are parallel.

  In one embodiment, a frustrated cube assembly is disclosed. The frustrated cube assembly includes a first prism, a second prism, and an inclined mirror. The first prism includes a first surface, a second surface, and a first slope. The second prism includes a third surface, a fourth surface, and a second slope. The first slope and the second slope face each other and are separated by an air gap. The tilt mirror is adjacent to the second surface, and the tilt mirror and the second surface are separated by a second air gap.

  In another embodiment, a frustrated cube assembly is disclosed. The frustrated cube assembly includes a first prism, a second prism, an inclined mirror, and a digital micromirror device. The first prism includes a first surface, a second surface, and a first slope. The second surface is a window, and the second surface is inclined. The second prism includes a third surface, a fourth surface, and a second slope. The first slope and the second slope face each other and are separated by a first air gap. The tilt mirror is adjacent to the second surface, and the tilt mirror and the second surface are separated by a second air gap. The digital micromirror device is adjacent to the third surface.

  In yet another embodiment, a frustrated cube assembly is disclosed. The frustrated cube assembly includes a first prism and a second prism. The first prism includes a first surface, a second surface, and a first slope. The second surface is a reflective diffraction grating. The second prism includes a third surface, a fourth surface, and a second slope. The first slope and the second slope face each other and are separated by an air gap.

In order that the above-described structure of the present disclosure may be understood in detail, a more specific description of the present disclosure briefly summarized above will be given with reference to the embodiments. Some embodiments are shown in the accompanying drawings. However, the attached drawings only illustrate exemplary embodiments of the present disclosure, and thus should not be construed as limiting the scope, and the present disclosure may include other equally effective embodiments. It should be noted.
1 is a perspective view of a system that can benefit from the embodiments disclosed herein. FIG. 1 is a schematic diagram of an illumination system of an image projection system that can benefit from the embodiments disclosed herein. FIG. 1 is a perspective view of an image projection device that can benefit from the embodiments disclosed herein. FIG. 1 is a schematic view of a frustrated cube assembly according to one embodiment. FIG. FIG. 6 is a schematic view of a frustrated cube assembly according to another embodiment. It is the schematic of the mirror array of the digital micromirror device which concerns on one Embodiment. It is sectional drawing of one of the optical relays concerning one Embodiment.

  To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the drawings. Further, elements of one embodiment can be advantageously adapted for use in other embodiments described herein.

Detailed description

  The present disclosure generally includes a first prism, a first prism including a first surface, a second surface, and a first slope, a second prism, The present invention relates to a frustrated cube assembly having a surface, a fourth surface, and a second prism including a second slope. The first and second slopes face each other and are separated by an air gap. The frustrated cube assembly can include an inclined mirror adjacent to the second surface. The second surface can be a reflective diffraction grating. Light is reflected through the image projection system along a single optical axis to a digital micromirror device (DMD) adjacent to the frustrated cube assembly at normal incidence. The direction of light incident on the DMD is such that the light reflected from the “on” mirror is directed at 45 degrees to the slope along the normal of the DMD surface. The input light beam and the output light beam are parallel.

  FIG. 1 is a perspective view of a system 100 that benefits from the embodiments disclosed herein. The system 100 includes a base frame 110, a slab 120, two or more stages 130, and a processing device 160. The base frame 110 can be placed on the floor of the manufacturing facility and can support the slab 120. A passive air isolator 112 can be disposed between the base frame 110 and the slab 120. The slab 120 can be a single element of granite, and two or more stages 130 can be placed on the slab 120. The substrate 140 can be supported by each of the two or more stages 130. A plurality of holes (not shown) can be formed in the stage 130 to allow a plurality of lift pins (not shown) to pass therethrough. The lift pins can be raised to an extended position to receive the substrate 140 (eg, from one or more transfer robots (not shown)). One or more transfer robots can be used to load and unload the substrate 140 from two or more stages 130.

  The substrate 140 is made of glass, for example, and can be used as a part of a flat panel display. In other embodiments, the substrate 140 may be made of other materials. In some embodiments, the substrate 140 can have a photoresist layer formed thereon. The photoresist is sensitive to radiation and can be a positive photoresist or a negative photoresist, where the portion of the photoresist exposed to radiation is exposed after the pattern has been written to the photoresist. It means soluble or insoluble in the photoresist developer applied to the resist, respectively. The chemical composition of the photoresist determines whether the photoresist is a positive photoresist or a negative photoresist. For example, the photoresist can include at least one of diazonaphthoquinone, phenol formaldehyde resin, poly (methyl methacrylate), poly (methyl glutarimide), and SU-8. In this way, a pattern can be generated on the surface of the substrate 140 to form an electronic circuit.

  The system 100 can further include a pair of supports 122 and a pair of tracks 124. The pair of supports 122 may be disposed on the slab 120, and the slab 120 and the pair of supports 122 may be a single element material. The pair of tracks 124 can be supported by the pair of supports 122, and the two or more stages 130 can move in the X direction along the tracks 124. In one embodiment, the pair of tracks 124 are coplanar with the pair of parallel magnetic channels. As illustrated, each track 124 of the pair of tracks 124 is linear. In other embodiments, the track 124 may have a non-linear shape. An encoder 126 may be coupled to each stage 130 to provide position information to a controller (not shown).

  The processing device 160 can include a support 162 and a processing unit 164. The support 162 can be disposed on the slab 120 and can include an opening 166 for two or more stages 130 to pass under the processing unit 164. The processing unit 164 can be supported by the support 162. In one embodiment, the processing unit 164 is a pattern generator configured to expose a photoresist in a photolithography process. In some embodiments, the pattern generator can be configured to perform a maskless lithography process. The processing unit 164 can include a plurality of image projection devices (shown in FIGS. 2-3). In one embodiment, the processing unit 164 can include 84 image projection devices. Each image projection device is disposed in the case 165. The processing device 160 can be used to perform maskless direct patterning. During operation, one of the two or more stages 130 moves in the X direction from the loading position to the processing position, as shown in FIG. The processing position can refer to one or more positions of the stage 130 as the stage 130 passes under the processing unit 164. In operation, two or more stages 130 can be supported by a plurality of air bearings (not shown) and can move along a pair of tracks 124 from a loading position to a processing position. In order to stabilize the movement of the stage 130 in the Y direction, a plurality of guide air bearings (not shown) may be coupled to each stage 130 and disposed adjacent to the inner wall 128 of each support body 122. Each of the two or more stages 130 may also move in the Y direction by moving along the track 150 to process and / or index the substrate 140. Each of the two or more stages 130 can operate independently, and can scan the substrate 140 in one direction and step in the other direction. In some embodiments, when one of the two or more stages 130 is scanning the substrate 140, the other of the two or more stages 130 unloads the exposed substrate 140 and exposes it. The next substrate 140 to be loaded is loaded.

  The measurement system measures the X and Y lateral position coordinates of each of the two or more stages 130 in real time, so that each of the plurality of image projectors accurately determines the pattern written on the photoresist-covered substrate. Can be positioned. The metrology system also provides real-time measurement of the angular position about the vertical or Z axis of each of the two or more stages 130. Angular position measurement can be used to keep the angular position constant during scanning by the servo mechanism, or it can be used to apply corrections to the position of the pattern written on the substrate 140 by the image projector. be able to. These techniques may be used in combination.

  FIG. 2 is a schematic diagram of an illumination system 392 of an image projection system that can benefit from the embodiments described herein. The illumination system 392 includes a light source 272, a light pipe 271, a plurality of lenses (two are shown) 274a, 274b, a plurality of mirrors (two are shown) 275a, 275b, a beam splitter 279, an illumination intensity detector. 276, and white light diode 278 can be included. The light source 272 can be a light emitting diode (LED) or a laser, and the light source 272 can be capable of generating light having a predetermined wavelength. In one embodiment, the predetermined wavelength is in the blue or near ultraviolet (UV) range, such as less than about 450 nm.

  During operation, a light beam 273 having a predetermined wavelength (eg, a wavelength in the blue region) is generated by the light source 272. The light beam 273 travels through the light pipe 271 and is reflected from the mirror 274 a to the beam splitter 279. The light beam 273 is then projected from the illumination system 392 toward the frustrated cube assembly 288 of the projection system 394 shown in FIG.

  FIG. 3 is a cross-sectional view of an image projection device 390 that can benefit from the embodiments disclosed herein. Illumination enters the image projection device 390 from the left hand side where the frustrated cube assembly 288 is located and exits to the right side where the substrate is located. Projection system 394 includes a frustrated cube assembly 288. The projection system also includes various subcomponents (unsigned) including, but not limited to, beam splitters, focus sensors, detector arrays for viewing the substrate, one or more image transducers, focus motors, focus groups, and projection windows. ) Can be included.

  The frustrated cube assembly 288 can have various embodiments as shown in FIGS. FIG. 4 is a schematic diagram of a frustrated cube assembly 400 according to one embodiment. The frustrated cube assembly 400 includes a first prism 402 and a second prism 404. The first prism 402 has a first surface 406, a second surface 408, and a first slope 410. The second prism 404 includes a third surface 412, a fourth surface 414, and a second slope 416. The first prism 402 and the second prism 404 can be offset from each other, whereby the corner where the first surface 406 and the first inclined surface 410 intersect is the third surface 412 and the second inclined surface. 416 is offset from the intersecting corner. Similarly, the corner where the second surface 408 and the first inclined surface 410 intersect is offset from the corner where the fourth surface 414 and the second inclined surface 416 intersect. The first surface 406 and the second surface 408 intersect at an angle exceeding 90 degrees. The third surface 412 and the fourth surface 414 are perpendicular to each other and therefore intersect at an angle of 90 degrees. The first slope 410 and the second slope 416 face each other and are separated by the first air gap 420. The first air gaps 420 may be uniformly spaced throughout. The frustrated cube assembly 400 also includes a tilting mirror 418. The tilt mirror is adjacent to the second surface 408. The tilt mirror 418 and the second surface 408 are separated by a second air gap 422. In one embodiment, the major axis of the tilting mirror 418 is parallel to the second surface 408. In another embodiment, the major axis of tilting mirror 418 is not parallel to second surface 408. In other words, the second air gap 422 may be uniformly spaced throughout. The frustrated cube assembly 400 further includes a DMD 280. DMD 280 may be adjacent to third surface 412. DMD 280 may be separated from third surface 412 by DMD air gap 424. The DMD air gap 424 may be uniformly spaced throughout.

  DMD 280 includes a plurality of micromirrors 634 disposed within mirror array 632 as shown in FIG. The edge 636 of the micromirror 634 is disposed along orthogonal axes that can be the X axis and the Y axis. These axes are consistent with the stage coordinate system after considering a similar axis associated with the substrate 140 or the 90 degree fold introduced by the frustrated cube assembly 288. However, the hinge 638 of each micromirror 634 is located at the opposite corner of each mirror that causes a pivot about 45 degrees with respect to the X and Y axes. Each of the plurality of micromirrors 634 can be inclined by an angle with respect to the horizontal plane of the mirror array 632. These mirrors can be switched between an on position and an off position by changing the tilt angle of the mirror. Depending on whether the light hits a mirror that is turned on or off, the light is either sent through the rest of the image projection system 390 or not used, respectively. In one embodiment, unused light is directed to an optical dump (not shown). In one embodiment, DMD 280 is made such that the only stable position of each micromirror 634 is at a tilt angle of plus or minus 12 degrees relative to the surface of mirror array 632. In order to reflect the incident light perpendicular to the surface of the mirror array 632, the incident light is in the incident plane rotated by twice the mirror tilt angle (24 degrees) and 45 degrees with respect to the X axis and the Y axis. Must be incident. The DMD 280 is disposed flat with respect to the projection of the substrate 140. In other words, the tilt direction of the mirror 418 or the direction of the grating lines in the diffraction grating 508 must be rotated 45 ° about the vertical axis, thereby creating an illumination beam on the DMD 280, which is tilted micro After being reflected in the vertical direction by the mirror 634, it is reflected downward at the center of the projection system 394.

  The tilt mirror 418 can be tilted at a second angle relative to the second surface 408. This adjustment is used to change the incident angle of the illumination beam on the DMD micromirror 634 and is equal to twice the DMD mirror tilt angle, which can vary ± 1 °. The first angle and the second angle may be equally opposite to the normal of the DMD 280 surface.

  In operation, the light beam 273 enters the frustrated cube assembly through the first surface 406. Next, the light beam 273 is reflected from the first inclined surface 410 and reflected upward through the second surface 408. The second surface 408 can be a window so that the light beam 273 travels through the second surface 408 to the tilt mirror 418. Thereafter, the light beam 273 is reflected from the tilt mirror 418 at an angle (θ), and the second surface 408, the first slope 410, the first air gap 420, the second slope 416, To the DMD 280 through the surface 412. The tilt mirror 418 performs fine adjustment with respect to the direction of the illumination beam incident on the DMD in order to correct the fluctuation of the DMD micro mirror tilt angle. The light beam 273 is then reflected from the DMD 280 through the third surface 412 to the second slope 416. Thereafter, the light beam 273 is reflected from the second ramp 416 through the fourth surface 414 to the projection system 394 and finally transmitted to the substrate 140 therethrough.

  The second surface 408 or tilting mirror 418 is tilted at the same angle with respect to the angle of the digital micromirror of the digital micromirror device. For example, when the tilt of the micromirror 634 is ± 12 degrees, the tilt mirror 418 must be tilted by 12 degrees, so that the light beam 273 reflected therefrom is tilted by 24 degrees (double angle when reflected). The An angle of 24 degrees is sufficient to allow the light beam 273 to pass through the first air gap 420 at an angle, for example, reflection from a DMD “on” mirror tilted by +12 degrees is perpendicular to the DMD 280. Reflected and totally reflected from the 45 degree surface in the first air gap 420. The light beam 273 striking a DMD “off” mirror tilted by −12 degrees is reflected at 12 + 24 degrees from the mirror normal and 48 degrees from the DMD normal. This unnecessary illumination is thrown away in the light dump. The tilt axis of the micromirror 634 is rotated 45 degrees with respect to the rectangular dimensions of the DMD 280 and the normal Z and X axes. Therefore, the tilt direction of the mirror 418 must also be rotated 45 degrees. As a result of the tilt direction of the last fold mirror in the path of the light beam 273, the axis of the optical path prior to entering the frustrated cube assembly 400 is X and X from the axis of the projection system disposed on the opposite side of the frustrated cube assembly 400. Offset in both directions of Y.

  Furthermore, there may be a slight change in the tilt angle from one DMD to another. For example, the change can be ± 1 degree. Since the tilt mirror 418 is separated from the second surface 408, the change can be absorbed by slightly changing the tilt angle of the tilt mirror 418. For example, in order to maintain the reflection angle from the micromirror perpendicular to the DMD plane, the tilt angle of the tilt mirror 418 can be varied ± 1 degree.

FIG. 5 is a schematic diagram of a frustrated cube assembly 500 according to another embodiment. The frustrated cube assembly 500 includes a first prism 502 and a second prism 504. The first prism 502 has a first surface 506, a second surface 508, and a first slope 510. The second prism 504 has a third surface 512, a fourth surface 514, and a second slope 516. The first prism 502 and the second prism 504 can be offset from each other, so that the corner where the first surface 506 and the first inclined surface 510 intersect is the third surface 512 and the second inclined surface. 516 is offset from the intersecting corner. Similarly, the corner where the second surface 508 and the first slope 510 intersect is offset from the corner where the fourth surface 514 and the second slope 516 intersect. The first inclined surface 410 and the second inclined surface 516 face each other and are separated by a first air gap 520. The first surface 506 and the second surface 508 are perpendicular to each other and intersect at an angle of 90 degrees. The third surface 512 and the fourth surface 514 are perpendicular to each other and intersect at an angle of 90 degrees. The second surface 508 can be a reflective diffraction grating. Diffraction from the diffraction grating surface 508 produces a diffraction angle (θ). The relationship between the distance between the diffraction gratings and the diffraction angle is determined by Equation 1 which is an expression of the diffraction grating.
mλ = d (sin θ)
(Formula 1)
In Equation 1, m is an integer that determines the diffraction order, λ is a wavelength, d is a grating period, and θ is a diffraction angle.

  The diffraction grating of the second surface 508 can be generated by any suitable process for generating a diffraction grating, including lithography processes and etching processes. The diffraction grating is etched into the second surface 508 so that the height of the first prism 502 is different from the height of the second prism 504. The frustrated cube assembly 500 further includes a DMD 280. DMD 280 may be adjacent to the third surface. DMD 280 can be spaced from third surface 512 by DMD air gap 524. The DMD air gap 524 may be uniformly spaced throughout.

  In operation, the light beam 273 enters the frustrated cube assembly through the first surface 506. Next, the light beam 273 is reflected from the first slope 510 to the second surface 508. Next, the light beam 273 is diffracted from the second surface 508 and travels to the DMD 280 through the first inclined surface 510, the air gap 520, the second inclined surface 516, and the third surface 512. Next, the light beam 273 is reflected from the on-mirror of the DMD 280 through the third surface 512 to the second slope 516. The light beam 273 is then reflected from the second ramp 516 through the fourth surface 514 to the projection system 394 and ultimately projects the light beam 273 onto the substrate 140.

  FIG. 7 is a cross-sectional view of an optical relay 742 according to an embodiment. The optical elements including the relay 742 are aligned along a single optical axis that passes through the frustrated cube assembly 288, the DMD 280 and the beam splitter 744, and the refractive lens component. The pattern generated by DMD 280 is finally projected onto the substrate through focus group 746 and projection window 748.

  The frustrated cube assembly 288 minimizes the footprint of each image projection device 390 by keeping the direction of illumination flow approximately perpendicular to the substrate 140 anywhere from the light source 272 generating exposure illumination to the substrate focal plane. To help.

  By using the frustrated cube assembly in the image projection apparatus, light loss is minimized, and many projection systems can be arranged side by side in the width direction of the flat panel substrate. Therefore, a plurality of image projection devices can be aligned in one system. More specifically, by adjusting the angle of the tilting mirror, the light reflected from the micromirror is adapted to adapt to variations in the average tilting angle of the DMD micromirror so that the input light beam is parallel to the output light beam. The direction of is aligned with the optical axis.

  While the above is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be created without departing from the basic scope of the present disclosure, the scope of which is as follows: It is determined based on the range.

Claims (15)

A frustrated cube assembly,
A first prism,
The first aspect;
A second side;
A first prism including a first slope;
A second prism,
The third aspect,
The fourth aspect;
A second prism including a second slope, wherein the first slope and the second slope are opposed to each other, and the first slope and the second slope are separated by a first air gap. When,
And a tilting mirror, the tilting mirror being adjacent to the second surface, wherein the tilting mirror and the second surface are separated by a second air gap.   The frustrated cube assembly of claim 1, comprising a digital micromirror device adjacent to the third surface.   The frustrated cube assembly of claim 2, wherein the first surface and the second surface intersect at an angle greater than about 90 degrees, and the third surface and the fourth surface are perpendicular.   4. The frustrated cube assembly of claim 3, wherein the second surface is a window and the second surface is inclined with respect to the third surface.   The frustrated cube assembly of claim 4, wherein the second surface is inclined at the same angle with respect to the angle of the digital micromirror of the digital micromirror device.   The frustrated cube assembly of claim 4, wherein the tilt mirror is parallel to the second surface. A frustrated cube assembly,
A first prism,
The first aspect;
A second surface which is a window and is inclined;
A first prism including a first slope;
A second prism,
The third aspect,
The fourth aspect;
A second prism including a second slope, wherein the first slope and the second slope are opposed to each other, and the first slope and the second slope are separated by a first air gap. When,
An inclined mirror, wherein the inclined mirror is adjacent to the second surface, and the inclined mirror and the second surface are separated by a second air gap;
A frustrated cube assembly comprising a digital micromirror device adjacent to the third surface.   The digital micromirror device includes a plurality of mirrors, and each mirror of the plurality of mirrors of the digital micromirror device can be tilted by a first angle with respect to a horizontal plane of the digital micromirror device. Frustrated cube assembly.   The frustrated cube assembly of claim 8, wherein the tilt mirror is at a second angle relative to the first surface.   The frustrated cube assembly of claim 9, wherein the first angle and the second angle are equal and are opposite to the normal of the surface of the digital micromirror device.   The second surface is tilted by 12 degrees, the central illumination beam is incident on the digital micromirror device at 24 degrees, and the second surface is perpendicular to the tilt axes of the plurality of mirrors of the digital micromirror device. The frustrated cube assembly according to claim 10.   The frustrated cube assembly of claim 11, wherein the tilting mirror is parallel to the second surface. A frustrated cube assembly,
A first prism,
The first aspect;
A second surface that is a reflective diffraction grating;
A first prism including a first slope;
A second prism,
The third aspect,
The fourth aspect;
A second prism including a second slope, wherein the first slope and the second slope face each other, and the first slope and the second slope are separated by an air gap. Frustrated cube assembly.   14. The frustration of claim 13, wherein the first surface and the fourth surface are parallel, the second surface and the third surface are parallel, and the first surface and the second surface are perpendicular to each other. Cube assembly.   15. The frustrated cube assembly of claim 14, wherein the direction of the grating lines of the reflective diffraction grating is rotated 45 degrees about the vertical axis.