Method for manufacturing liquid crystal based electro-optical modulator for flat panel display inspection using surface MEMS technology

Abstract

An electro-optical modulator is a liquid crystal-based electro-optical modulator. The liquid crystal based electro-optical modulator is fabricated using surface microelectromechanical systems (MEMS) technology. The electro-optical modulator is used to inspect flat panel displays or the like. The electro-optical modulator is manufactured using surface MEMS technology to substantially thin the electro-optical modulator and allow the use of pure liquid crystals, without the need for thick sealing plates.

Description

[0001] CROSS REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 406,712, filed on September 14, 2022, entitled “METHOD FOR FABRICATING ALIQUID-CRYSTAL-BASED ELECTRO-OPTICAL LIGHT MODULATOR USING SURFACE MEMSTECHNIQUES FOR INSPECTION FLAT PANEL DISPLAYS,” under 35 U.S.C. §119(e), the entire text of which is incorporated herein by reference. Technical Field

[0003] The present invention relates generally to electro-optics and, more particularly, to liquid crystal materials for use in electro-optical applications. Background Art

[0004] Electro-optic modulators that use liquid crystals (specifically, Nematic Curve Alignment (NCAP) films or Polymer Dispersed Liquid Crystal (PDLC) films) for modulation are used to test the conductivity of thin film transistors and interconnects of flat panel displays (FPDs) in manufacturing. Electro-optic modulators are made using a mechanical process by glue, Mylar TM Mechanical manufacturing of thick stack sub-assemblies of NCAP films, protective film dielectric mirrors and hard coatings on.

[0005] Electro-optic modulators are subject to high variability and performance tradeoffs resulting in increased noise, reduced dynamic range, and decreased sensitivity. For example, a NCAP film having a thickness of 12 or 25 microns will have a 20% thickness variation. Therefore, it would be advantageous to provide devices, systems, and methods that address the above-mentioned shortcomings. Summary of the invention

[0006] According to one or more embodiments of the present disclosure, an electro-optic modulator is described. The electro-optic modulator includes a glass substrate. The electro-optic modulator includes a transparent electrode disposed on the glass substrate. The electro-optic modulator includes a first alignment layer disposed on the transparent electrode. The electro-optic modulator includes a liquid crystal layer disposed on the first alignment layer. The electro-optic modulator includes a second alignment layer disposed on the liquid crystal layer. The electro-optic modulator includes a polymer layer disposed on the second alignment layer. The electro-optic modulator includes a plurality of polymer pillars. The plurality of polymer pillars extend through at least a portion of the liquid crystal layer. The plurality of polymer pillars mechanically support the polymer layer. The electro-optic modulator includes a dielectric reflector disposed on the polymer layer. The electro-optic modulator includes a hard coating disposed on the dielectric reflector.

[0007] In some embodiments, the liquid crystal layer comprises a thickness between 2 microns and 5 microns.

[0008] In some embodiments, the liquid crystal layer is not a nematic phase or a polymer dispersed liquid crystal.

[0009] In some embodiments, the plurality of polymer pillars extend from the polymer layer through the second alignment layer and at least the portion of the liquid crystal layer.

[0010] In some embodiments, the electro-optic modulator includes a plurality of alignment posts. The plurality of alignment posts extend from the second alignment layer to the first alignment layer. The plurality of polymer posts extend through at least the portion of the liquid crystal layer to the alignment posts. The plurality of polymer posts are disposed on the plurality of alignment posts.

[0011] In some embodiments, the electro-optic modulator includes an anti-reflective coating. The glass substrate is disposed on the anti-reflective coating.

[0012] In some embodiments, the plurality of polymer pillars extend from the second alignment layer through the liquid crystal layer to the first alignment layer. The plurality of polymer pillars are separated from the polymer layer by the second alignment layer.

[0013] In some embodiments, the plurality of polymer pillars each comprise a width less than 1.4 microns and a thickness between 2 and 5 microns.

[0014] In some embodiments, each of the plurality of polymer pillars comprises a sidewall angle between 83° and 93°.

[0015] In some embodiments, the transparent electrode includes at least one of indium tin oxide (ITO) or silver nanowires.

[0016] In some embodiments, the first alignment layer and the second alignment layer each include at least one of silicon oxynitride or silicon dioxide.

[0017] In some embodiments, the first alignment layer and the second alignment layer each comprise a refractive index between 1.51 and 1.55.

[0018] In some embodiments, the polymer layer and the plurality of polymer pillars each include a cross-linked polymer.

[0019] In some embodiments, the dielectric mirror has a reflectivity greater than 80% for light having a wavelength between 570 nm and 670 nm.

[0020] In some embodiments, the dielectric mirror is a stack of repeating layers of silicon nitride and silicon dioxide.

[0021] In some embodiments, the dielectric mirror is a stack of repeating layers of zirconium oxide and silicon dioxide.

[0022] In some embodiments, the electro-optic modulator includes an epoxy seal. The epoxy seal seals the liquid crystal layer between the first alignment layer and the second alignment layer.

[0023] According to one or more embodiments of the present disclosure, an imaging system is described. The imaging system includes an illumination source configured to generate illumination. The imaging system includes a stage for a sample. The imaging system includes a detector for generating an image of at least a portion of the sample. The imaging system includes an electro-optic modulator disposed in the path of the illumination from the illumination source and separated from the sample by an air gap. The electro-optic modulator includes a glass substrate. The electro-optic modulator includes a transparent electrode disposed on the glass substrate. The electro-optic modulator includes a first alignment layer disposed on the transparent electrode. The electro-optic modulator includes a liquid crystal layer disposed on the first alignment layer. The electro-optic modulator includes a second alignment layer disposed on the liquid crystal layer. The electro-optic modulator includes a polymer layer disposed on the second alignment layer. The electro-optic modulator includes a plurality of polymer pillars. The plurality of polymer pillars extend through at least a portion of the liquid crystal layer. The plurality of polymer pillars mechanically support the polymer layer. The electro-optic modulator includes a dielectric reflector disposed on the polymer layer. The electro-optic modulator includes a hard coating disposed on the dielectric reflector.

[0024] According to one or more embodiments of the present disclosure, an electro-optic modulator is described. The electro-optic modulator includes a glass substrate. The electro-optic modulator includes a transparent electrode disposed on the glass substrate. The electro-optic modulator includes a first alignment layer disposed on the transparent electrode. The electro-optic modulator includes a liquid crystal layer disposed on the first alignment layer. The electro-optic modulator includes a second alignment layer disposed on the liquid crystal layer. The electro-optic modulator includes a plurality of alignment posts. The plurality of alignment posts extend from the second alignment layer through the liquid crystal layer to the first alignment layer. The electro-optic modulator includes a dielectric reflector disposed on the second alignment layer. The electro-optic modulator includes a plurality of dielectric pillars. The plurality of dielectric pillars extend from the dielectric reflector through a first portion of the liquid crystal layer to the plurality of alignment posts. The plurality of dielectric pillars are disposed on the plurality of alignment posts. The electro-optic modulator includes a polymer layer disposed on the dielectric reflector. The electro-optic modulator includes a plurality of polymer pillars. The plurality of polymer pillars extend from the polymer layer through the dielectric reflector, the second alignment layer and a second portion of the liquid crystal layer to the plurality of dielectric pillars. The plurality of polymer pillars are disposed on the plurality of dielectric pillars.

[0025] In some embodiments, the liquid crystal layer comprises a thickness between 2 microns and 5 microns.

[0026] In some embodiments, the liquid crystal layer is not a nematic phase or a polymer dispersed liquid crystal. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Many advantages of the present disclosure may be better understood by those skilled in the art by referring to the accompanying drawings, in which:

[0028] Figure 1A Depicted is a cross-sectional view of an electro-optic modulator in accordance with one or more embodiments of the present disclosure.

[0029] Figure 1B Depicted is a top view of a liquid crystal layer, polymer pillars, alignment pillars, and epoxy seal of an electro-optic modulator according to one or more embodiments of the present disclosure.

[0030] Figure 2A to 2B A flow chart depicting a method for producing an electro-optic modulator according to one or more embodiments of the present disclosure.

[0031] Figures 2C to 2N Depicted is a cross-sectional view of an electro-optic modulator during a method according to one or more embodiments of the present disclosure.

[0032] Figure 3 Depicted is a cross-sectional view of an electro-optic modulator in accordance with one or more embodiments of the present disclosure.

[0033] Figures 4A to 4BA flow chart depicting a method for producing an electro-optic modulator according to one or more embodiments of the present disclosure.

[0034] Figures 4C to 4M Depicted is a cross-sectional view of an electro-optic modulator during a method according to one or more embodiments of the present disclosure.

[0035] Figure 5 Depicted is a cross-sectional view of an electro-optic modulator in accordance with one or more embodiments of the present disclosure.

[0036] Figure 6 A simplified diagram depicting an imaging system in accordance with one or more embodiments of the present disclosure. DETAILED DESCRIPTION

[0037] The present disclosure has been particularly shown and described with respect to specific embodiments and specific features thereof. The embodiments described herein should be considered as illustrative rather than limiting. It should be readily apparent to one of ordinary skill in the art that various changes and modifications may be made to the form and details without departing from the spirit and scope of the present disclosure. Reference will now be made in detail to the disclosed objects illustrated in the accompanying drawings.

[0038] Embodiments of the present disclosure generally relate to electro-optic modulators, methods for manufacturing electro-optic modulators, and imaging systems using electro-optic modulators. The electro-optic modulators are liquid crystal based electro-optic modulators. The liquid crystal based electro-optic modulators are manufactured using surface micro-electromechanical systems (MEMS) technology. The electro-optic modulators are used to inspect flat panel displays or the like. The use of surface MEMS technology to manufacture the electro-optic modulators thins the electro-optic modulators to a considerable extent and allows the use of pure liquid crystals without the need for thick sealing plates.

[0039] Each of the following is incorporated herein by reference in its entirety: U.S. Patent No. 5,432,461, entitled “Method of testing active matrix liquid crystal display substrates”; U.S. Patent No. 7,817,333, filed on February 6, 2007, entitled “Modulator with improved sensitivity and life time”; U.S. Patent No. 8,801,964, filed on December 22, 2010, entitled “Encapsulated polymer network liquid crystal material, device and applications”; U.S. Patent No. 7,639,319, filed on April 7, 2005, entitled “Polymer dispersed liquid crystal formulations for modulator fabrication”; U.S. Patent No. 6,151,153, entitled “Modulator transfer process and assembly”.

[0040] Reference Figure 1A to 1B , describes an electro-optic (EO) modulator 100 according to one or more embodiments of the present disclosure. The electro-optic modulator 100 may also be referred to as an electro-optic modulator, a liquid crystal based electro-optic modulator, and the like. The electro-optic modulator 100 is a flat panel display (FPD) spatial light modulator (SLM). The electro-optic modulator 100 is a narrow bandgap device having two dielectric layers separated by polymer pillars and an integrated dielectric mirror.

[0041] The electro-optic modulator 100 may include one or more films, layers, or coatings. One or more film layers selectively allow light to pass through. For example, the electro-optic modulator 100 may include one or more layers, such as, but not limited to, an anti-reflective coating 102, a glass substrate 104, a transparent electrode 106, an alignment layer 108, a liquid crystal layer 110, alignment posts 112, polymer posts 114, an epoxy seal 115, an alignment layer 116, a polymer layer 118, a dielectric mirror 120, a hard coating 122, and the like.

[0042] In some embodiments, the electro-optic modulator 100 includes an anti-reflective coating 102. The anti-reflective coating 102 may also be referred to as a dielectric anti-reflective layer stack.

[0043] In some embodiments, the electro-optic modulator 100 includes a glass substrate 104. The glass substrate 104 may include BK-7 glass or the like. The glass substrate 104 is disposed on the anti-reflective coating 102.

[0044] In some embodiments, the electro-optic modulator 100 includes a transparent electrode 106. The transparent electrode 106 may refer to a transparent conductive layer. The transparent electrode 106 is disposed on the glass substrate 104. The transparent electrode 106 may include any conductive coating that is transparent to the wavelength of interest. For example, the transparent electrode 106 may include a material such as, but not limited to, indium tin oxide (ITO), silver nanowires, conductive polythiophene, carbon nanotubes. The material may be applied to the glass substrate via sputtering and masking techniques or the like. The transparent electrode 106 may include a thickness. For example, the transparent electrode 106 may include and In some embodiments, the transparent electrode 106 may include and The thickness between and <1.8% variation on the transparent electrode 106. The transparent electrode 106 can couple with the sample capacitance to induce a local voltage and similarly an electric field. The local voltage can generate an electric field.

[0045] In some embodiments, the electro-optic modulator 100 includes an alignment layer 108. The alignment layer 108 is disposed on the transparent electrode 106. The alignment layer 108 is a dielectric. The alignment layer 108 is disposed between the liquid crystal layer 110 and the transparent electrode 106. By being a dielectric and disposed between the liquid crystal layer 110 and the transparent electrode 106, the alignment layer 108 insulates the liquid crystal layer 110 from the transparent electrode 106. The alignment layer 108 includes a refractive index (n). For example, the alignment layer 108 may include a refractive index between 1.51 and 1.55. The alignment layer 108 may include any material that is a dielectric and includes a desired refractive index. In some embodiments, the alignment layer 108 is silicon oxynitride (SiOxNy). In some embodiments, the alignment layer 108 is silicon dioxide (SiO2). The alignment layer 108 includes a thickness. For example, the alignment layer 108 may include and The alignment layer may generally refer to a layer that helps align the liquid crystal layer 110. The alignment layer may also be referred to as a photoresponsive layer because the alignment layer is formed of a photoresponsive material. The photoresponsive material may be photopatterned to produce an alignment layer for a liquid crystal material.

[0046] In some embodiments, the alignment layer 108 is etched. The alignment layer 108 is etched with one or more grooves (not depicted). A groove may also refer to a continuous nano-channel, line, or the like. The groove may be made by etching, plasma ashing, and stripping. In some embodiments, the groove is etched with a depth. For example, the groove may be etched with a depth of In some embodiments, the grooves define a checkerboard pattern in the alignment layer 108. The alignment layer 108 includes a line spacing (LS). The line spacing is the distance between the grooves. In some embodiments, the line spacing may be 350 nm or less. In some embodiments, the line spacing may be 120 nm or less. In some embodiments, the line spacing may be 110 nm or less. Although the electro-optic modulator 100 is described as including the alignment layer 108, this is not intended to be a limitation of the present disclosure. It is contemplated that the transparent electrode 106 may be etched with one or more grooves.

[0047] In some embodiments, the electro-optic modulator 100 includes a liquid crystal layer 110. The liquid crystal layer 110 is disposed on the alignment layer 108. In some embodiments, the liquid crystal layer 110 is inserted between the alignment layer 108 and the alignment layer 116 by vacuum or filled by capillary action. In some embodiments, the liquid crystal layer 110 is discontinuous. The alignment pillars 112 and the polymer pillars 114 extend through the liquid crystal layer 110.

[0048] The liquid crystal layer 110 can sense electric fields. When an electric field is applied across the liquid crystal, the optical properties of the liquid crystal layer 110 change. The intensity of light transmitted through the liquid crystal layer 110 is modulated by the variation in the intensity of the electric field across the liquid crystal layer 110. The light transmitted through the liquid crystal layer 110 can change depending on the magnitude of the electric field applied to the liquid crystal layer 110. The electric field causes the liquid crystal layer 110 to align along the direction of the electric field.

[0049] In some embodiments, the liquid crystal layer 110 is a pure liquid crystal. The pure liquid crystal is a nematic liquid crystal. The liquid crystal layer 110 is aligned along a surface when an electric field is not present. The liquid crystal layer 110 is aligned along a surface when an electric field is not present due to the alignment layer 108 and the alignment layer 116. The liquid crystal layer 110 is not a polymer / liquid crystal composite layer. For example, the liquid crystal layer 110 is not a nematic curve alignment phase (NCAP) or a polymer dispersed liquid crystal (PDLC). In this regard, the liquid crystal in the liquid crystal layer 110 is not encapsulated as a droplet in a polymer. The liquid crystal layer 110 includes a thickness. For example, the liquid crystal layer 110 includes a thickness between 2 microns (um) and 5 microns. The liquid crystal layer 110 is significantly thinner than a polymer / liquid crystal composite NCAP or PDLC material. Modulator sensitivity and defect detectability should be significantly enhanced by utilizing pure liquid crystals rather than NCAP or PDLC. Therefore, the electro-optic modulator 100 provides higher sensitivity and throughput for detecting defects during flat panel display manufacturing.

[0050] In some embodiments, the electro-optic modulator 100 includes alignment posts 112. The alignment posts 112 are disposed on or below the alignment layer 108. The alignment posts 112 separate the polymer posts 114 from the liquid crystal layer 110. In some embodiments, the alignment posts 112 are used in a form to manufacture the polymer posts 114. The alignment posts 112 extend from the alignment layer 108 up to the alignment layer 116. The alignment posts 112 may include a thickness. For example, the alignment posts 112 may include a thickness of 0.3um + / - 0.012um. The alignment posts 112 define one or more openings between the alignment posts 112. The liquid crystal layer 110 is added to the electro-optic modulator 100 through the openings. In some embodiments, the openings are sealed by glue. For example, the openings may be sealed by UV curable glue, epoxy, or the like.

[0051] In some embodiments, the electro-optic modulator 100 includes a polymer pillar 114. The polymer pillar 114 may include a corrosion-resistant material. The polymer pillar 114 is made of a cross-linkable photoresponsive polymer. For example, the polymer pillar 114 may include, but is not limited to, polyimide (PI).

[0052] The polymer pillars 114 mechanically support the polymer layer 118. For example, the polymer pillars 114 bear the weight of the polymer layer 118 into the alignment layer 108. In some embodiments, the polymer pillars 114 bear the weight of the polymer layer 118 into the alignment layer 108 through the alignment pillars 112. The polymer pillars 114 extend through at least a portion of the liquid crystal layer 110. In some embodiments, the polymer pillars 114 extend from the polymer layer 118. The polymer pillars 114 extend from the polymer layer 118 through the alignment layer 116 and at least a portion of the liquid crystal layer 110. In some embodiments, the polymer pillars 114 extend through at least a portion of the liquid crystal layer 110 to the alignment pillars 112. In some embodiments, the polymer pillars 114 are disposed on the alignment pillars 112.

[0053] The polymer column 114 may include a width. The width of the polymer column 114 may be based on the width of the support structure 211 minus twice the thickness of the alignment column 112 (e.g., for both sides of the polymer column 114). The polymer column 114 includes a width of less than 1.4um. In some embodiments, the polymer column 114 includes a width between 0.776um and 0.824um. The electro-optic modulator 100 includes a pitch between the polymer columns 114. The pitch defines the distance between the center of one of the columns 114 to the center of the adjacent one of the columns 114. In some embodiments, the electro-optic modulator 100 includes a pitch between the polymer columns 114 between 10um and 20um. In some embodiments, the polymer column 114 includes a thickness. For example, the polymer column 114 may include a thickness between 2um and 5um. In some embodiments, the polymer column 114 includes a sidewall angle. The sidewall angle of the polymer column 114 may be between 83° and 93°. The sidewall angle of 90° is orthogonal to the alignment layer 108. The polymer pillars 114 may be viewed as including a concave profile and / or utilizing a bread-like accumulation.

[0054] In some embodiments, the electro-optic modulator 100 includes an epoxy seal 115. The epoxy seal 115 may also be referred to as a glue seal. The epoxy seal 115 seals the liquid crystal layer 110 between the alignment layer 108 and the alignment layer 116. The epoxy seal 115 is disposed around the edge of the liquid crystal layer 110. The epoxy seal 115 seals the liquid crystal layer 110 to prevent the liquid crystal material from overflowing. The epoxy seal 115 is disposed in the opening defined between the polymer pillars 114.

[0055] In some embodiments, the electro-optic modulator 100 includes an alignment layer 116. The alignment layer 116 is disposed on or below the liquid crystal layer 110. The alignment layer 116 is a dielectric. The alignment layer 116 includes a refractive index (n). For example, the alignment layer 116 may include a refractive index between 1.51 and 1.55. The alignment layer 116 may include any material that is a dielectric and includes a desired refractive index. In some embodiments, the alignment layer 116 is silicon oxynitride (SiOxNy). In some embodiments, the alignment layer 116 is silicon dioxide (SiO2). The alignment layer 116 includes a thickness. For example, the alignment layer 116 may include and As another example, the alignment layer 116 may include and The thickness between.

[0056] In some embodiments, the electro-optic modulator 100 includes a polymer layer 118. The polymer layer 118 may also refer to a polymer layer, a polymer film, or the like. The polymer layer 118 is disposed on the alignment layer 116. The alignment layer 108 and the alignment layer 116 are between the polymer layer 118 and the glass substrate 104. The polymer layer 118 may include a corrosion-resistant material. The polymer layer 118 is made of a cross-linkable photoresponsive polymer. For example, the polymer layer 118 may include, but is not limited to, polyimide (PI). Polyimide is highly cross-linked to survive in a corrosive environment. The polymer layer 118 includes a thickness. For example, the polymer layer 118 includes a thickness between 4um and 6um. Therefore, the polymer layer 118 and the polymer pillars 114 each include a cross-linked polymer, such as polyimide.

[0057] In some embodiments, the electro-optic modulator 100 includes a dielectric mirror 120. The dielectric mirror 120 may also be referred to as an overcoat dielectric mirror, a quarter-wavelength mirror, or the like. The dielectric mirror 120 is disposed or coated on the polymer layer 118. In some embodiments, the dielectric mirror 120 is bonded to the polymer layer 118 by a carbonyl bond. The dielectric mirror 120 has a reflectivity for light having a desired wavelength. For example, the dielectric mirror 120 has a reflectivity greater than 80% for light having a wavelength between 570 nm and 670 nm. The dielectric mirror 120 may include a thickness. For example, the dielectric mirror 120 has a thickness of about 1 um. For example, the dielectric mirror 120 may have a thickness between 0.9 um and 1.1 um.

[0058] The dielectric reflector is a multilayer dielectric reflector. The multilayer dielectric reflector includes a first material and a second material. The dielectric reflector 120 may start with a first material layer and end with a second material layer. In this regard, the dielectric reflector 120 may be coated as follows: a first material layer, a second material layer, ..., a first material layer. The dielectric reflector 120 may include any number of first material layers and second material layers. For example, the dielectric reflector 120 may include 6 first material layers and 5 second material layers, for a total of 11 layers. The first material layer and the second material layer each include a thickness. The thickness depends on the refractive index of the dielectric reflector 120. In some embodiments, the first material layer has + / -10% thickness. In some embodiments, the second material layer has + / -10% thickness. The first material and the second material may include any suitable material. For example, the dielectric reflector may be silicon nitride (SiN x) / silicon dioxide (SiO2) multilayer dielectric reflector. Silicon nitride may be the first material and silicon dioxide may be the second material. As another example, the dielectric reflector 120 may be a zirconium dioxide (ZrO2) / silicon dioxide (SiO2) multilayer dielectric reflector. Zirconium dioxide may be the first material and silicon dioxide may be the second material. As another example, the dielectric reflector 120 may be hafnium oxide (HfO2) and the second material may be silicon oxide. In some embodiments, the first material may be any element from Group 4B of the periodic table.

[0059] In some embodiments, the dielectric mirror 120 includes an overcoat. The overcoat may be disposed adjacent to the polymer layer 118.

[0060] In some embodiments, the electro-optic modulator 100 includes a hard coating 122. The hard coating 122 is disposed on the dielectric reflector 120. The hard coating 122 protects the dielectric reflector 120. The hard coating 122 is a photodefinable hard coating. In some embodiments, the hard coating 122 includes an organic hard coating. The hard coating 122 may include the composition of the hard coating described in U.S. Pat. No. 7,099,067. The hard coating 122 includes a thickness. For example, the hard coating 122 includes a thickness between 2.37um and 5um. The hard coating 122 includes a hardness. In some embodiments, the hard coating 122 includes a hardness exceeding a 5H pencil hardness. The hard coating 122 may include a primary hard coating and a thinner slip agent layer.

[0061] Reference Figures 2A to 2N , describing a method 200 according to one or more embodiments of the present disclosure. A method may also refer to a process of manufacturing an electro-optic modulator. The embodiments and enabling techniques described herein previously in the context of the electro-optic modulator 100 should be interpreted as extending to the method. However, it should be further noted that the method is not limited to the architecture of the electro-optic modulator. The method 200 is a single-piece manufacturing technique in which silicon (Si) or silicon germanium (SiGe) is used as a sacrificial layer and a release layer on a glass substrate.

[0062] At step 202, a glass substrate 104 is provided. The glass substrate 104 is disposed on the anti-reflective coating 102.

[0063] At step 204, a transparent electrode 106 is deposited on the glass substrate 104 by sputtering deposition.

[0064] At step 206, the alignment layer 108 is deposited on the transparent electrode 106. The alignment layer 108 is deposited on the transparent electrode 106 by chemical vapor deposition (CVD). For example, the alignment layer 108 is deposited on the transparent electrode 106 by plasma enhanced chemical vapor deposition (PECVD).

[0065] The step may also include patterning one or more trenches in the alignment layer 108. The one or more trenches are patterned by etching, plasma ashing, and stripping. For example, the one or more trenches may be patterned by 248nm phase shift mask (PSM), 193nm photolithography, or the like.

[0066] In step 208, a sacrificial layer 209 is deposited. The sacrificial layer 209 includes a sacrificial layer 209a deposited on the alignment layer 108. The sacrificial layer 209 includes a sacrificial layer 209b deposited under the anti-reflective coating 102. The sacrificial layer 209 is deposited by CVD. For example, the sacrificial layer 209 is deposited by PECVD, low pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), or the like. The sacrificial layer 209 may include amorphous silicon (a-Si), polycrystalline silicon (poly-Si), polycrystalline silicon germanium (poly-SiGe), or the like. In some embodiments, the sacrificial layer 209a on the alignment layer 108 is a-Si deposited by PECVD. In some embodiments, the sacrificial layer 209b under the anti-reflective coating 102 is poly-Si or poly-SiGe deposited by one of LPCVD, PECVD, or APCVD. It is anticipated that depositing poly-Si and / or poly-SiGe by LPCVD may cause the glass substrate 104 to warp, such that PECVD or APCVD may be desirable.

[0067] The step may include patterning one or more trenches (not depicted) in a sacrificial layer 209a disposed on the alignment layer 108. The one or more trenches are patterned by etching, plasma ashing, and stripping. For example, the one or more trenches may be patterned by 193 nm photolithography or the like. The one or more trenches include a line spacing of 120 nm or less. The trenches form nano-trench in the a-Si.

[0068] In step 210, a support structure 211 is patterned in a sacrificial layer 209a disposed on the alignment layer 108. The support structure 211 is patterned by photolithography, plasma etching, and stripping. Overetching from the sacrificial layer 209a into the alignment layer 108 may be allowed. The support structure 211 provides support when forming the alignment posts 112 and the polymer posts 114. The support structure 211 includes a pitch, a width, a height, and a sidewall angle. For example, the support structure 211 includes a pitch between adjacent ones of the support structure 211 between 10um and 20um. As another example, the support structure 211 includes a width of 1.4um. As another example, the support structure 211 includes a thickness between 2um and 5um. As another example, the support structure 211 includes a sidewall angle between 83° and 93°.

[0069] At step 212, the alignment posts 112 and the alignment layer 116 are deposited on the sacrificial layer 209a disposed on the alignment layer 108. For example, the alignment posts 112 are deposited in the support structure 211. The alignment posts 112 and the alignment layer 116 are deposited by chemical vapor deposition (CVD). For example, the alignment posts 112 and the alignment layer 116 are deposited by plasma enhanced chemical vapor deposition (PECVD). The alignment posts 112 and the alignment layer 116 may include stress. For example, the alignment posts 112 and the alignment layer 116 may include a tensile stress between 50 MPa and 150 MPa.

[0070] In step 214, the polymer pillars 114 and the polymer layer 118 are spin-coated and cured. For example, the polymer pillars 114 are spin-coated into the support structure, onto the alignment pillars 112. As another example, the polymer layer 118 is spin-coated onto the alignment layer 116. The polymer pillars 114 and the polymer layer 118 can be cross-linked by exposure. The polymer pillars 114 and the polymer layer 118 can also be applied with a developer. The developer can remove the uncross-linked portions of the polymer pillars 114 and the polymer layer 118. The polymer pillars 114 and the polymer layer 118 are cured at a temperature. The polymer pillars 114 and the polymer layer 118 are cured at a high temperature to reduce the shrinkage of the polymer pillars 114. The shrinkage of the polymer pillars 114 is undesirable because the shrinkage can cause the polymer pillars 114 to separate from the alignment pillars 112. In some embodiments, the polymer pillars 114 and the polymer layer 118 are cured at a temperature between 350°C and 400°C. In some embodiments, polymer pillars 114 and polymer layer 118 are spin-coated as liquid polyimide, which is then hardened during a cure.

[0071] At step 216, the dielectric reflector 120 is deposited on the polymer layer 118. The dielectric reflector 120 is deposited on the polymer layer 118 by PECVD or sputtering deposition. In some embodiments, the dielectric reflector 120 is deposited on the polymer layer 118 by forming a SiN x The dielectric reflector 120 is deposited on the polymer layer 118 by forming a repeating layer of ZrO2 and SiO2. In some embodiments, the dielectric reflector 120 is deposited on the polymer layer 118 by forming a repeating layer of ZrO2 and SiO2. The dielectric reflector 120 may include stress. For example, the dielectric reflector 120 may include a tensile stress between 50 MPa and 150 MPa. In some embodiments, the polymer layer 118 is pre-treated by CF4 / O2 etching to form carbonyl bonds on the polymer layer 118 for improving the adhesion of the dielectric reflector 120 to the polymer layer 118.

[0072] At step 218, active areas 219 are patterned from the electro-optic modulator 100. The active array 219 is patterned using photoresist (PR) stripping. Photoresist (PR) stripping is compatible with the polymer layer 118. The active area 219 may also be referred to as modulation defined. In some embodiments, the active area 219 is patterned based on the critical dimension (CD) of the array to be tested. The active area 219 is patterned through the dielectric reflector 120, the polymer layer 118, the alignment layer 116, the sacrificial layer, the alignment layer 108. In some embodiments, the active area 219 is patterned up to the transparent electrode 106s. In some embodiments, the active area 219 is patterned into the transparent electrode 106. For example, the active area 219 may be patterned up to the transparent electrode 106. middle.

[0073] In a step 220, a hard coating 122 is deposited on the dielectric mirror 120. In some embodiments, the hard coating 122 is spin coated and cured on the dielectric mirror 120. The hard coating 122 may be cured using a low temperature (LT) cure to prevent the dielectric mirror 120 from cracking.

[0074] At step 222, the sacrificial layer is removed. The sacrificial layer can be removed by gluing, sawing, debonding, back etching, and releasing. In some embodiments, the polymer layer 118 is re-anchored on the edge to strain the polymer layer 118 from tensile stress. Once the sacrificial layer is removed, the electro-optic modulator 100 defines a cavity between the alignment layer 108 and the alignment layer 116. The electro-optic modulator 100 may also define one or more openings. The cavity may be entered through the one or more openings. The one or more openings are defined on the edge of the active area.

[0075] At step 224, a liquid crystal layer 110 is added between the alignment layer 108 and the alignment layer 116. The liquid crystal layer 110 is added through one or more openings. In some embodiments, the liquid crystal layer 110 is added by vacuum insertion or capillary action. For example, the liquid crystal layer 110 can be added through a cavity by capillary action. Adding the liquid crystal layer 110 through a cavity by capillary action is different from the lamination method used to manufacture NCAP modulators or PDLC modulators. The step may further include sealing the one or more openings with an epoxy seal 115.

[0076] Reference Figure 3 , describes an electro-optic modulator 300 according to one or more embodiments of the present disclosure. The entire discussion of electro-optic modulator 100 is incorporated herein by reference into electro-optic modulator 300.

[0077] The electro-optic modulator 300 may include one or more films, layers, or coatings. One or more film layers selectively allow light to pass through. For example, the electro-optic modulator 300 may include one or more layers, such as, but not limited to, a glass substrate 104, a transparent electrode 106, an alignment layer 108, a liquid crystal layer 110, a polymer pillar 114, an epoxy seal 115, an alignment layer 116, a polymer layer 118, a dielectric mirror 120, a hard coating 122, and the like. The entire discussion of the glass substrate 104, transparent electrode 106, alignment layer 108, liquid crystal layer 110, polymer pillar 114, epoxy seal 115, alignment layer 116, polymer layer 118, dielectric mirror 120, and hard coating 122 of the electro-optic modulator 100 is hereby incorporated by reference into the electro-optic modulator 300. The electro-optic modulator 300 is different from the electro-optic modulator 100 in that the electro-optic modulator 100 includes the alignment post 112, while the electro-optic modulator 300 does not include the alignment post 112. The electro-optic modulator 300 is also different from the electro-optic modulator 100 in that the polymer post 114 of the electro-optic modulator 100 extends from the polymer layer 118 and is not separated from the polymer layer 118, while the polymer post 114 of the electro-optic modulator 300 is separated from the polymer layer 118 by the alignment layer 116.

[0078] In some embodiments, polymer pillars 114 extend from alignment layer 116. Polymer pillars 114 are separated from polymer layer 118 by alignment layer 116. Thus, polymer pillars 114 may or may not extend from polymer layer 118. Polymer pillars 114 extend from alignment layer 116 up to alignment layer 108. Polymer pillars 114 are disposed on alignment layer 108. Polymer pillars 114 mechanically support polymer layer 118 by bearing the weight of polymer layer 118 to alignment layer 108 through alignment layer 116 and polymer pillars 114. In this example, electro-optic modulator 300 does not include alignment pillars 112. In some embodiments, polymer pillars 114 extend through the entire liquid crystal layer 110. For example, polymer pillars 114 extend through liquid crystal layer 110 up to alignment layer 108.

[0079] Reference Figures 4A to 4M , describing a method 400 according to one or more embodiments of the present disclosure. A method may also refer to a process of manufacturing an electro-optic modulator. The embodiments and enabling techniques described previously herein in the context of electro-optic modulator 100, method 200, and electro-optic modulator 300 should be interpreted as extending to the method. However, it should be further noted that the method is not limited to the architecture of electro-optic modulator 100, method 200, and electro-optic modulator 300. Method 400 is a two-piece manufacturing technique having a Si substrate that is released and polymerized flip-bonded to a glass substrate.

[0080] In step 402, silicon nitride (SiN x ) layer is deposited on the Si substrate 403. SiNx The layers are deposited by CVD. For example, SiN x The layer is deposited by LPCVD at 106. SiN x The layer has a thickness. For example, SiN x Layer has Thickness.

[0081] In step 404, the dielectric mirror 120 is deposited on the SiN x The dielectric reflector 120 is deposited by PECVD or sputtering deposition. SiN x The dielectric reflector 120 is formed by forming a SiN x The dielectric reflector 120 may include stress. For example, the dielectric reflector 120 may include a tensile stress between 50 MPa and 150 MPa.

[0082] At step 406, the polymer layer 118 is spun on and cured. The polymer layer 118 is spun on and cured on the dielectric mirror 120. The polymer layer 118 is cured at a temperature. The polymer layer 118 is cured at a high temperature to reduce stress in the dielectric mirror 120 due to shrinkage of the polymer layer 118. In some embodiments, the polymer layer 118 is cured at a temperature between 350° C. and 400° C. In some embodiments, the polymer layer 118 is spun on as a liquid polyimide, which then hardens during curing. The polymer layer 118 may be spun on with a thickness between 3.8 um and 4.2 um.

[0083] At step 408, an alignment layer 116 is deposited on the polymer layer 118. The alignment layer 116 is deposited by CVD. For example, the alignment layer 116 is deposited by PECVD. In some embodiments, the alignment layer 116 is deposited to have a thickness of 1000 Å. For example, the alignment layer 116 is deposited to have a thickness of 1000 Å. and The thickness between.

[0084] The steps may also include patterning one or more grooves in the alignment layer 116. The one or more grooves are patterned by etching, plasma ashing, and stripping. In some embodiments, the grooves are etched to a depth. For example, the grooves may be etched to a depth of In some embodiments, the grooves define a checkerboard pattern in the alignment layer 116. The alignment layer 116 includes a line spacing (LS). The line spacing is the distance between the grooves. In some embodiments, the line spacing may be 300 nm or less. In some embodiments, the line spacing may be 110 nm or less.

[0085] At step 410, polymer pillars 114 are deposited on alignment layer 116. In some embodiments, two masks may be used to deposit polymer pillars 114. In some embodiments, polymer pillars 114 may be deposited by using alignment with one mask. In some embodiments, polymer pillars 114 are post-treated with O2 / CF4 to form carbonyl bonds between polymer pillars 114 and alignment layer 116 for improving adhesion of polymer pillars 114 to alignment layer 116.

[0086] At step 412, the transparent electrode 106 is deposited on the glass substrate 104 by sputter deposition. In this aspect, the glass substrate 104 is not disposed on the anti-reflective coating 102.

[0087] At step 414, an alignment layer 108 is deposited on the transparent electrode 106. The alignment layer 108 is deposited on the transparent electrode 106 by chemical vapor deposition (CVD). For example, the alignment layer 108 is deposited on the transparent electrode 106 by plasma enhanced chemical vapor deposition (PECVD). The alignment layer 108 may require a deep ultraviolet (DUV) polarizer mask to align within a desired period of time.

[0088] The steps of depositing the transparent electrode 106 on the glass substrate 104 and depositing the alignment layer 108 can be performed by depositing the silicon nitride (SiN x ) layer on the Si substrate 403, depositing the dielectric reflector 120, spin coating and curing the polymer layer 118, and depositing the alignment layer 116 on the polymer layer 118 are performed before, at the same time, or after the steps of.

[0089] At step 416, the alignment layer 108 is bonded to the polymer pillars 114. The glass substrate 104, the transparent electrode 106, and the alignment layer 108 are flipped and aligned to the polymer pillars 114. The alignment layer 108 is bonded to the polymer pillars 114 by vacuum pressing. The alignment layer 108 is pressed at the glass transition temperature of the polymer pillars 114. For example, the polymer pillars 114 may include a glass transition temperature between 150° C. and 200° C.

[0090] At step 418, the Si substrate is released from the dielectric mirror 120. The Si substrate is released from the dielectric mirror 120 by etching the Si substrate. For example, the Si substrate may be etched by potassium hydroxide (KOH) or the like. The edges of the polymer layer 118 may be clamped during edge etching. In some embodiments, the polymer layer 118 requires patterning and a protective layer on the edges, which depends on the fixture and etching solution.

[0091] At step 420, a hard coating 122 is deposited on the dielectric mirror 120. In some embodiments, the hard coating 122 is spin coated and cured on the dielectric mirror 120. The hard coating 122 may be cured using a low temperature (LT) cure to prevent the dielectric mirror 120 from cracking.

[0092] At step 422, a liquid crystal layer 110 is added between the alignment layer 108 and the alignment layer 116. The liquid crystal layer 110 is added through one or more openings. In some embodiments, the liquid crystal layer 110 is added by vacuum or capillary insertion. For example, the liquid crystal layer 110 may be added through a cavity by capillary action. Adding the liquid crystal layer 110 through a cavity by capillary action is different from the lamination method used to make NCAP modulators or PDLC modulators and will prevent future damage to the LC sensor when the top polyester film is removed during the assembly process. The steps may further include sealing the one or more openings with an epoxy seal 115. In some embodiments, edge trimming / sealing is required without upstream definition etching.

[0093] Reference Figure 5 , describes an electro-optic modulator 500 according to one or more embodiments of the present disclosure. The entire discussion of electro-optic modulator 100 and electro-optic modulator 300 is incorporated herein by reference into electro-optic modulator 500 .

[0094] The electro-optic modulator 100 may include one or more films, layers, or coatings. One or more film layers selectively allow light to pass through. For example, the electro-optic modulator 100 may include one or more layers, such as, but not limited to, an anti-reflective coating 102, a glass substrate 104, a transparent electrode 106, an alignment layer 108, a liquid crystal layer 110, alignment posts 112, polymer posts 114, an epoxy seal 115, an alignment layer 116, a polymer layer 118, a dielectric mirror 120, a hard coating 122, and the like. The entire discussion of the anti-reflective coating 102, the glass substrate 104, the transparent electrode 106, the alignment layer 108, the liquid crystal layer 110, the alignment posts 112, the polymer posts 114, the epoxy seal 115, the alignment layer 116, the polymer layer 118, the dielectric mirror 120, and the hard coating 122 of the electro-optic modulator 100 is hereby incorporated by reference into the electro-optic modulator 500. The electro-optic modulator 500 also includes a dielectric pillar 502 .

[0095] Electro-optic modulator 500 is similar to electro-optic modulator 100, except that electro-optic modulator 500 has a dielectric mirror 120 between alignment layer 116 and polymer layer 118. Dielectric mirror 120 is disposed on alignment layer 116. Polymer layer 118 is disposed on dielectric mirror 120.

[0096] The alignment posts 112 extend from the alignment layer 116 through the liquid crystal layer 110 to the alignment layer 108. The alignment posts 112 are used to fabricate the dielectric posts 502 in a form.

[0097] The electro-optic modulator 500 includes a dielectric post 502. The dielectric post 502 extends from the dielectric mirror 120. The dielectric post 502 extends from the dielectric mirror 120 through a first portion of the liquid crystal layer 110. The dielectric post 502 extends from the dielectric mirror 120 through the first portion to the alignment post 112. The dielectric post 502 is disposed on the alignment post 112. The alignment post 112 separates the dielectric post 502 from the liquid crystal layer 110. The alignment post 112 also separates the dielectric post 502 from the alignment layer 108. The dielectric post 502 is used in a form to make a polymer post 114.

[0098] Electro-optic modulator 500 includes polymer pillars 114. Polymer pillars 114 extend from polymer layer 118. Polymer pillars 114 extend from polymer layer 118 through dielectric mirrors 120 and alignment layer 116. Polymer pillars 114 extend from polymer layer 118 through dielectric mirrors 120 and alignment layer 116 through a second portion of liquid crystal layer 110 to dielectric pillars 502. The second portion of liquid crystal layer 110 is smaller than the first portion of liquid crystal layer 110. In this regard, dielectric pillars 502 extend further into liquid crystal layer 110 than polymer pillars 114. Polymer pillars 114 are disposed on dielectric pillars 502. Dielectric pillars 502 separate alignment pillars 112 from polymer pillars 114.

[0099] Electro-optic modulator 500 may be fabricated by a process similar to method 200. Although method 200 is described as including spin coating and curing polymer pillars 114 and polymer layer 118 and then depositing dielectric mirror 120, this is not intended to be a limitation of the present disclosure. In some embodiments, dielectric mirror 120 may be deposited prior to spin coating and curing polymer pillars 114 and polymer layer 118. Dielectric mirror 120 may then include dielectric pillars 502 disposed in a support structure on alignment pillars 112. Polymer layer 118 may then be deposited on dielectric mirror 120 and polymer pillars 114 may then be deposited in a support structure on dielectric pillars 502. The steps in this method may be considered a mirror-first process rather than a polymer layer-first process. In some embodiments, a mirror-first process may use a photodefinable polymer layer 118.

[0100] Figure 6 600 according to one or more embodiments of the present disclosure. For purposes of the present disclosure, the term "imaging system" may be interchangeable with the term "imaging tool." The imaging system 600 may also refer to an automated optical inspection (AOI) system, a voltage imaging optical system (VIOS), an array inspector, and the like.

[0101] The imaging system 600 may generally include any type of imaging tool suitable for, for example, but not limited to, voltage imaging. Voltage imaging may be used to detect and measure defects in flat-panel thin-film transistor (TFT) arrays. The performance of a TFT array is simulated as if the TFT array were assembled into a TFT cell and then the characteristics of the TFT array are measured by indirectly measuring the actual voltage distribution on the panel (or so-called voltage imaging) using an electro-optic modulator (100, 300, 500). Voltage imaging may be performed by the imaging system 600. The imaging system 600 may include one or more components for inspecting such TFT arrays or other samples.

[0102] The electro-optic modulator (100, 300, 500) can facilitate a number of imaging tasks, such as modulating the light source of the imaging system 600 to assist in detecting one or more defects of the sample 611, such as (but not limited to) a thin film transistor (TFT) array, a liquid crystal display (LCD) panel, an OLED panel, and the like. The TFT array can be formed on a substrate (such as a transparent plate of thin glass). The TFT array can include one or more printed layers. The printed layers can be formed on the substrate by a number of processes, such as (but not limited to) one or more material deposition steps, one or more photolithography steps, one or more etching steps, and the like. Manufacturing can occur in stages, where materials (such as indium tin oxide (ITO), etc.) are deposited over previous layers or on a glass substrate according to a process pattern. During manufacturing, the printed layers are manufactured within selected tolerances to properly construct the final device. The printed layers may exhibit defects outside of the selected tolerances. The characteristics of the TFT array can be measured by the imaging system 600 to detect defects.

[0103] In an embodiment, the imaging system 600 includes an illumination source 606 for generating illumination 608. The illumination 608 may include one or more selected wavelengths of light including, but not limited to, vacuum ultraviolet radiation (VUV), deep ultraviolet radiation (DUV), ultraviolet (UV) radiation, visible radiation, or infrared (IR) radiation. The illumination source 606 may further generate the illumination 608 including any range of selected wavelengths. In an embodiment, the illumination source 606 may include a spectrally tunable illumination source for generating the illumination 608 having a tunable spectrum.

[0104] In an embodiment, an illumination source 606 directs illumination 608 to a sample 611 via an illumination path 609. The illumination path 609 may include one or more lenses 612 or additional illumination optical components 614 suitable for modifying and / or adjusting the illumination 608. For example, the one or more illumination optical components 614 may include, but are not limited to, one or more polarizers, one or more filters, one or more beam splitters, one or more diffusers, one or more homogenizers, one or more apodizers, one or more shapers, one or more shutters (e.g., mechanical shutters, electro-optic shutters, acousto-optic shutters, or the like), one or more aperture stops, and / or one or more field stops.

[0105] In an embodiment, the imaging system 600 includes an electro-optic modulator 100. The electro-optic modulator (100, 300, 500) is disposed in the path of illumination 608 from an illumination source 606. The electro-optic modulator (100, 300, 500) can modulate one or more characteristics of the illumination 608. During operation, light is transmitted through a portion of the electro-optic modulator (100, 300, 500) and defects can be detected by observing changes in reflected or transmitted light. The electro-optic modulator (100, 300, 500) is separated from a sample 611 by an air gap. The electro-optic modulator (100, 300, 500) can be placed a selected number of microns (e.g., between 5 microns and 75 microns) above the surface of the sample 611 (e.g., a TFT array) and a voltage bias is applied across a transparent electrode of a layer of indium tin oxide (hereinafter referred to as "ITO") on the surface of the electro-optic modulator (100, 300, 500). Thereafter, the electro-optic modulator (100, 300, 500) is capacitively coupled to the sample 611 so that the electric field associated with the sample 611 is sensed by one or more layers (e.g., layers containing liquid crystal) of the electro-optic modulator (100, 300, 500). The intensity of incident light transmitted through the liquid crystal of the electro-optic modulator varies (i.e., modulated) based on the intensity of the electric field felt by the liquid crystal. For example, in the area where normal pixels are located, a local voltage potential (e.g., capacitive coupling between the sample 611 and the electro-optic modulator (100, 300, 500)) is applied to cause one or more films of the electro-optic modulator 100 to be locally translucent. In the locally translucent area, light from the light source 606 is allowed to pass through the electro-optic modulator (100, 300, 500) and reflect from the sample 611 to pass through the collection path 622 (e.g., for capture by the detector 604). As another example, in regions where no voltage potential is applied (e.g., no capacitive coupling), one or more films of the electro-optic modulator (100, 300, 500) remain locally opaque. In the case where the electro-optic modulator (100, 300, 500) is locally opaque, light from the light source 606 is scattered or otherwise prevented from passing to the sample 611. Thus, a transmission voltage (TV) curve can be determined by applying a voltage. The intrinsic switching voltage of the electro-optic modulator 100 can correspond to a voltage across the electro-optic modulator (100, 300, 500) where light transmission through the electro-optic modulator (100, 300, 500) is most sensitive to voltage changes. For example, the switching voltage can correspond to an electric field strength where a given percentage of liquid crystal molecules are substantially aligned with the electric field to allow light transmission.

[0106] In an embodiment, the sample 611 includes a thin film transistor (TFT) array. For example, the sample 611 may include pixel elements disposed between inactive regions. The sample stage 618 may include any device suitable for positioning the sample 611 within the imaging system 600.

[0107] In an embodiment, the detector 604 is configured to capture radiation (e.g., sample light 620) emitted from the sample 611 through a collection path 622. For example, the collection path 622 may include (but does not necessarily include) an electro-optic modulator (100, 300, 500), a collection lens (e.g., an objective lens), or one or more additional collection path lenses 624. In this regard, the detector 604 may receive radiation reflected or scattered from the sample 611 (e.g., via specular reflection, diffuse reflection, and the like) or generated by the sample 611 (e.g., luminescence associated with absorption of illumination 608, or the like).

[0108] System 600 may include, but is not limited to, a controller 603. Controller 603 may include one or more processors and memory and may include or be coupled to a user interface 610.

[0109] The collection path 622 may further include any number of collection optical components 626 for directing and / or modifying the illumination collected by the electro-optic modulator (100, 300, 500), including, but not limited to, one or more collection path lenses 624, one or more filters, one or more polarizers, or one or more blockers. Additionally, the collection path 622 may include a field stop for controlling the spatial extent of the sample imaged onto the detector 604 or an aperture stop for controlling the angular extent of the illumination from the sample used to generate the image on the detector 604. In another embodiment, the collection path 622 includes an aperture stop positioned in a plane conjugate to the back focal plane of the optical element to provide telecentric imaging of the sample. In an embodiment, the system 600 includes a beam splitter 628 oriented so that the electro-optic modulator 100 can simultaneously direct the illumination 608 to the sample 611 and collect radiation emitted from the sample 611.

[0110] The detector 604 may include any type of optical detector suitable for measuring the illumination received from the sample 611. For example, the detector 604 may include, but is not limited to, a CCD detector, a TDI detector, a photomultiplier tube (PMT), an avalanche photodiode (APD), a complementary metal oxide semiconductor (CMOS) sensor, or the like. In another embodiment, the detector 604 may include a spectral detector suitable for identifying the wavelength of light emitted from the sample 611.

[0111] In an embodiment, the controller 603 is communicatively coupled to the detector 604. The controller 603 may include one or more processors configured to perform any of the various process steps. In an embodiment, the controller 603 is configured to generate and provide one or more control signals configured to perform one or more adjustments of one or more process tools based on the image signal 613 from the detector 604.

[0112] The one or more processors of the controller 603 may include any processor or processing element known in the art. For the purposes of the present disclosure, the term "processor" or "processing element" may be broadly defined to encompass any device having one or more processing or logic elements (e.g., one or more microprocessor devices, one or more application specific integrated circuit (ASIC) devices, one or more field programmable gate arrays (FPGAs), or one or more digital signal processors (DSPs)). In this sense, the one or more processors may include any device configured to execute algorithms and / or instructions (e.g., program instructions stored in a memory). In one embodiment, the one or more processors may be embodied as a desktop computer, a main computer system, a workstation, an image computer, a parallel processor, a network computer, or any other computer system configured to execute a process configured to operate or operate in conjunction with the imaging system 600, as described in the present disclosure. In addition, different subsystems of the system 600 may include processors or logic elements suitable for implementing at least a portion of the steps described in the present disclosure. Therefore, the above description should not be interpreted as a limitation of the embodiments of the present disclosure, but is merely illustrative. In addition, the steps described in the present disclosure may be implemented by a single controller or, alternatively, multiple controllers. Additionally, the controller 603 may include one or more controllers housed in a common housing or multiple housings. In this manner, any controller or combination of controllers may be individually packaged as a module suitable for integration into the imaging system 600. Furthermore, the controller 603 may analyze data received from the detector 604 and feed the data to additional components within the imaging system 600 or external to the imaging system 600.

[0113] The memory medium may include any storage medium known in the art to be suitable for storing program instructions that can be executed by the associated one or more processors. For example, the memory medium may include a non-transitory memory medium. As another example, the memory medium may include (but is not limited to) a read-only memory (ROM), a random access memory (RAM), a magnetic or optical storage device (such as a disk), a tape, a solid-state drive, and the like. It should be further noted that the memory medium may be housed in a common controller housing with the one or more processors. In one embodiment, the memory medium may be remotely located relative to the physical location of the one or more processors and the controller. For example, one or more processors of the controller 603 may access a remote memory (such as a server) that can be accessed via a network (such as the Internet, an intranet, and the like).

[0114] In an embodiment, the user interface 610 is coupled to the controller 603 via communication. In an embodiment, the user interface 610 may include, but is not limited to, one or more desktop computers, laptop computers, tablet computers, and the like. In an embodiment, the user interface 610 includes a display for displaying data of the system 600 to the user. The display of the user interface 610 may include any display known in the art. For example, the display may include, but is not limited to, a liquid crystal display (LCD), a display based on an organic light emitting diode (OLED), or a CRT display. Those skilled in the art will recognize that any display device capable of integrating with the user interface 610 is suitable for implementation in the present disclosure. In an embodiment, the user may input selections and / or instructions via a user input device of the user interface 610 in response to data displayed to the user.

[0115] Again, generally refer to Figures 1A to 6 It is contemplated that the electro-optic modulator (100, 300, 500) provides several benefits of NCAP-based EO modulators. The electro-optic modulator (100, 300, 500) improves noise, dynamic range, and defect sensitivity and reduces the threshold field of the modulator product to detect defects during flat panel manufacturing. The electro-optic modulator (100, 300, 500) achieves a desired flatness level. The electro-optic modulator (100, 300, 500) reduces part-to-part variations resulting from mechanical processes. The electro-optic modulator (100, 300, 500) includes the improved defect detection sensitivity and reduced threshold field required for defect metrology during manufacturing of flat panel displays.

[0116] In some embodiments, the electro-optic modulator (100, 300, 500) may include an area. For example, the electro-optic modulator (100, 300, 500) may include an area of ​​130 mm x 130 mm up to an area of ​​1 cm x 1 cm.

[0117] As used in the present disclosure, the term "sample" generally refers to a substrate formed of a semiconductor or non-semiconductor material (such as thin film glass or the like). For example, the semiconductor or non-semiconductor material may include (but is not limited to) single crystal silicon, gallium arsenide, indium phosphide, or glass material. The sample may include one or more layers. For example, such layers may include (but are not limited to) photoresists (including photoresists), dielectric materials, conductive materials, and semiconductive materials. Many different types of such layers are known in the art, and the term "sample" used herein is intended to cover samples on which all types of such layers can be formed. One or more layers formed on the sample may be patterned or unpatterned. For example, the sample may include multiple dies each having repeatable patterned features. The formation and processing of such material layers may ultimately lead to a completed device. Many different types of devices may be formed on the sample, and the term "sample" used herein is intended to cover samples on which any type of device known in the art is manufactured. In addition, for the purposes of the present disclosure, the terms "sample" and "wafer" should be interpreted as interchangeable. Additionally, for purposes of this disclosure, the terms "patterning device," "mask," and "reticle" should be interpreted as interchangeable.

[0118] It is further contemplated that each of the above method embodiments may include any other steps of any other method described herein. In addition, each of the above method embodiments may be performed by any of the systems described herein. In some embodiments, the method utilizes surface micro-electromechanical systems ("surface MEMS") manufacturing technology that can be used in silicon wafer foundries to produce the electro-optic modulator 100.

[0119] Those skilled in the art will recognize that the components, operations, devices, objects, and accompanying discussions described herein are used as examples to make the concepts clear and that various configuration modifications are contemplated. Therefore, as used herein, the specific examples and accompanying discussions set forth are intended to represent their more general categories. In general, the use of any specific example is intended to represent its category, and the non-inclusion of specific components, operations, devices, and objects should not be considered limiting.

[0120] As used herein, directional terms such as "top", "bottom", "above", "below", "up", "upward", "down", "below", and "downward" are intended to provide relative positions for descriptive purposes and are not intended to specify an absolute reference system. Various modifications to the described embodiments will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments.

[0121] With respect to the use of substantially any plural and / or singular terms herein, those skilled in the art may translate from the plural to the singular and / or from the singular to the plural as the context and / or application permits. For clarity, the various singular / plural arrangements are not explicitly set forth herein.

[0122] The objectives described herein sometimes illustrate different components contained in or connected to other components. It should be understood that such depicted architectures are for illustration only, and in fact, many other architectures that implement the same function can be implemented. Conceptually, any arrangement of components that implement the same function is effectively "associated" to achieve the desired function. Therefore, regardless of the architecture or intermediate components, any two components combined to achieve a specific function herein can be considered to be "associated" with each other to achieve the desired function. Similarly, any two components so associated can also be considered to be "connected" or "coupled" to achieve the desired function, and any two components that can be so associated can also be considered to be "coupleable" to each other to achieve the desired function. "Coupleable" specific examples include (but are not limited to) physically mixed and / or physically interactive components and / or wirelessly interactive and / or wirelessly interactive components and / or logically interactive and / or logically interactive components.

[0123] In addition, it should be understood that the present invention is defined by the appended claims. It should be understood by those skilled in the art that, in general, the terms used herein and in particular in the appended claims (e.g., the body of the appended claims) are generally intended to be "open" terms (e.g., the term "comprising" should be interpreted as "including (but not limited to)", the term "having" should be interpreted as "having at least", etc.). It should be further understood by those skilled in the art that if a specific number of claim recitations is intended to be introduced, then this intention should be clearly stated in the claims, and if there is no such statement, then there is no such intention. For example, as an aid to understanding, the appended claims may contain the use of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be interpreted as implying that the introduction of a claim recitation by the indefinite article "a" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even if the same claim contains the introductory phrase "one or more" or "at least one" and an indefinite article such as "a" (e.g., "a" should generally be interpreted as meaning "at least one" or "one or more"); the same applies to the use of definite articles used to introduce claim recitations. In addition, even if a specific number of introduced claim recitations is explicitly recited, those skilled in the art will recognize that such recitation should generally be interpreted as meaning at least the number of recitations (e.g., the bare recitation of "two recitations" without other modifiers generally means at least two recitations or two or more recitations). Furthermore, in examples where a convention similar to “at least one of A, B, and C, and the like” is used, this construction is generally intended to be what is commonly understood by those skilled in the art (e.g., “a system having at least one of A, B, and C” would include, but is not limited to, systems having only A, only B, only C, both A and B, both A and C, both B and C, and / or both A, B, and C, etc.). In examples where a convention similar to “at least one of A, B, or C, and the like” is used, this construction is generally intended to be what is commonly understood by those skilled in the art (e.g., “a system having at least one of A, B, or C” would include, but is not limited to, systems having only A, only B, only C, both A and B, both A and C, both B and C, and / or both A, B, and C, etc.). Those skilled in the art will further appreciate that virtually any disjunctive term and / or phrase presenting two or more alternatives, whether in the Detailed Description, claims, or drawings, should be understood to contemplate the possibility of including one of the terms, either of the two terms, or both of the terms. For example, the phrase "A or B" should be understood to include the possibility of "A" or "B" or "A and B".

[0124] It is believed that the present disclosure and many of its attendant advantages will be understood from the above description, and it should be understood that various changes can be made to the form, construction and arrangement of components without departing from the object of the present disclosure or sacrificing all of its material advantages. The described form is for illustration only and the appended claims are intended to cover and include such changes. In addition, it should be understood that the present invention is defined by the appended claims.

Claims

1. An electro-optic modulator, comprising: Glass substrate; A transparent electrode disposed on the glass substrate; A first alignment layer disposed on the transparent electrode; a liquid crystal layer disposed on the first alignment layer; a second alignment layer disposed on the liquid crystal layer; a polymer layer disposed on the second alignment layer; a plurality of polymer pillars; wherein the plurality of polymer pillars extend through at least a portion of the liquid crystal layer; in The plurality of polymer pillars mechanically supports the polymer layer; a dielectric reflector disposed on the polymer layer; and A hard coating is disposed on the dielectric mirror.

2. The electro-optic modulator of claim 1, wherein the liquid crystal layer comprises a thickness between 2 and 5 microns.

3. The electro-optic modulator of claim 1, wherein the liquid crystal layer is not a nematic phase or a polymer dispersed liquid crystal.

4. The electro-optic modulator of claim 1, wherein the plurality of polymer pillars extend from the polymer layer through the second alignment layer and at least the portion of the liquid crystal layer.

5. The electro-optic modulator of claim 4 , comprising a plurality of alignment posts; wherein the plurality of alignment posts extend from the second alignment layer to the first alignment layer; wherein the plurality of polymer posts extend through at least the portion of the liquid crystal layer to the alignment posts; and wherein the plurality of polymer posts are disposed on the plurality of alignment posts.

6. The electro-optic modulator of claim 5, comprising an anti-reflective coating; wherein the glass substrate is disposed on the anti-reflective coating.

7. The electro-optic modulator of claim 1, wherein the plurality of polymer pillars extend from the second alignment layer through the liquid crystal layer to the first alignment layer; wherein the plurality of polymer pillars are separated from the polymer layer by the second alignment layer.

8. The electro-optic modulator of claim 1, wherein the plurality of polymer pillars each comprise a width less than 1.4 microns and a thickness between 2 and 5 microns.

9. The electro-optic modulator of claim 8, wherein the plurality of polymer pillars each comprise a sidewall angle between 83° and 93°.

10. The electro-optic modulator of claim 1, wherein the transparent electrode comprises at least one of indium tin oxide (ITO) or silver nanowires.

11. The electro-optic modulator of claim 1, wherein the first alignment layer and the second alignment layer each comprise at least one of silicon oxynitride or silicon dioxide.

12. The electro-optic modulator of claim 1, wherein the first alignment layer and the second alignment layer each comprise a refractive index between 1.51 and 1.

55.

13. The electro-optic modulator of claim 1, wherein the polymer layer and the plurality of polymer pillars each comprise a cross-linked polymer.

14. The electro-optic modulator of claim 1, wherein the dielectric mirror has a reflectivity greater than 80% for light having a wavelength between 570 nm and 670 nm.

15. The electro-optic modulator of claim 1, wherein the dielectric mirror is a stack of repeating layers of silicon nitride and silicon dioxide.

16. The electro-optic modulator of claim 1, wherein the dielectric mirror is a stack of repeating layers of zirconium oxide and silicon dioxide.

17. The electro-optic modulator of claim 1, comprising an epoxy seal; wherein the epoxy seal seals the liquid crystal layer between the first alignment layer and the second alignment layer.

18. An imaging system comprising: an illumination source configured to generate illumination; a stage, which is used for the sample; a detector for generating an image of at least a portion of the sample; and an electro-optic modulator disposed in a path of the illumination from the illumination source and separated from the sample by an air gap, wherein the electro-optic modulator comprises: Glass substrate; A transparent electrode disposed on the glass substrate; A first alignment layer disposed on the transparent electrode; a liquid crystal layer disposed on the first alignment layer; a second alignment layer disposed on the liquid crystal layer; a polymer layer disposed on the second alignment layer; a plurality of polymer pillars; wherein the plurality of polymer pillars extend through at least a portion of the liquid crystal layer; wherein the plurality of polymer pillars mechanically support the polymer layer; a dielectric reflector disposed on the polymer layer; and A hard coating is disposed on the dielectric mirror.

19. An electro-optic modulator, comprising: Glass substrate; A transparent electrode disposed on the glass substrate; A first alignment layer disposed on the transparent electrode; a liquid crystal layer disposed on the first alignment layer; a second alignment layer disposed on the liquid crystal layer; a plurality of alignment posts; wherein the plurality of alignment posts extend from the second alignment layer through the liquid crystal layer to the first alignment layer; a dielectric mirror disposed on the second alignment layer; a plurality of dielectric pillars; wherein the plurality of dielectric posts extend from the dielectric reflector through a first portion of the liquid crystal layer to the plurality of alignment posts; wherein the plurality of dielectric posts are disposed on the plurality of alignment posts; a polymer layer disposed on the dielectric mirror; and a plurality of polymer pillars; wherein the plurality of polymer pillars extend from the polymer layer through the dielectric reflector, the second alignment layer, and a second portion of the liquid crystal layer to the plurality of dielectric pillars; wherein the plurality of polymer pillars are disposed on the plurality of dielectric pillars.

20. The electro-optic modulator of claim 19, wherein the liquid crystal layer comprises a thickness between 2 and 5 microns.

21. The electro-optic modulator of claim 19, wherein the liquid crystal layer is not a nematic phase or a polymer dispersed liquid crystal.

Images