Enhanced defect detection using planar macrocyclic dyes in liquid crystal thin films

Abstract

The present disclosure relates to a modulator material layer comprising a polymer matrix formed of a plurality of cross-linked polymer molecules and a plurality of liquid droplets of liquid crystal within the polymer matrix. A planar macrocycle dye is dispersed within the plurality of liquid droplets of liquid crystal. The planar macrocycle dye can comprise one or more of a phthalocyanine, a porphyrin, a naphthalocyanine, a metallophthalocyanine, a metalloporphyrin, or a metallo-naphthalocyanine.

Description

[0001] Cross Reference to Related Applications

[0002] This application claims priority to the non-provisional patent application No. 18 / 238,183, filed August 25, 2023, and assigned, and to the provisional patent application No. 63 / 402,079, filed August 30, 2022, the disclosure of which is hereby incorporated by reference. Technical Field

[0003] This disclosure relates to optoelectronics, and more specifically to macrocyclic dye doping in liquid crystal materials for enhancing defect detection in optoelectronic applications. Background Technology

[0004] Optoelectronic modulators using liquid crystals (especially nematic curvilinear aligned phases (NCAP) films or polymer-dispersed liquid crystal (PDLC) films) are used to test the conductivity of thin-film transistors and interconnects in manufactured flat panel displays (FPDs). Enhanced defect detection is encouraged to rapidly resolve smaller defects on FPDs. Existing modulators are limited in defect detection capabilities and have low sensitivity. Therefore, it would be advantageous to provide an apparatus, system, or method that improves some of the shortcomings described above. There is a need for systems and techniques to enhance defect detection using modulators and the sensitivity (S-curve) of modulators used in array inspectors. Summary of the Invention

[0005] A modulator material layer is provided in a first embodiment. The modulator material layer comprises: a polymer matrix formed of a plurality of cross-linked polymer molecules; a plurality of liquid crystal droplets within the polymer matrix; and a planar macrocyclic dye dispersed within the plurality of liquid crystal droplets. The planar macrocyclic dye may comprise one or more of the following: phthalocyanine, porphyrin, naphthalocyanine, metallophthalocyanine, metalloporphyrin, or metalnaphthalocyanine. In one example, the planar macrocyclic dye comprises one or more of phthalocyanine, porphyrin, or naphthalocyanine. In another example, the planar macrocyclic dye comprises one or more of metallophthalocyanine, metalloporphyrin, or metalnaphthalocyanine. For example, the planar macrocyclic dye may be zinc phthalocyanine.

[0006] The planar macrocyclic dye may be 0.002% to 0.5% by weight of the mixture of the polymer matrix, the liquid crystal, and the planar macrocyclic dye.

[0007] The modulator material layer can be a nematically aligned phase (NCAP) film. Alternatively, the modulator material layer can be a polymer-dispersed liquid crystal (PDLC) film, a palmitic liquid crystal film, a ferroelectric liquid crystal film, or a blue phase liquid crystal film.

[0008] The size of the droplets can range from 0.1 micrometers to 10 micrometers.

[0009] When no electric field is present, the liquid crystal can be randomly oriented within the plurality of droplets. When an electric field is applied across the modulator material layer, the liquid crystal can be at least partially aligned along the direction of the electric field.

[0010] The modulator material layer may further include a transparent conductive film disposed on the modulator material layer.

[0011] The modulator material layer may further comprise a glass substrate. The modulator material layer is either a direct coating on the glass substrate or a stack on the glass substrate.

[0012] A second embodiment provides an imaging system. The imaging system includes: an illumination source configured to generate illumination; a stage configured to hold a sample; a detector for generating an image of at least a portion of the sample; and a photoelectric modulator disposed in the path of illumination from the illumination source and separated from the sample by an air gap. The photoelectric modulator includes a transparent conductive film and a modulator material layer disposed on the transparent conductive film. The modulator material layer includes: a polymer matrix formed of a plurality of cross-linked polymer molecules; a plurality of liquid crystal droplets within the polymer matrix; and a planar macrocyclic dye dispersed within the plurality of liquid crystal droplets. The planar macrocyclic dye may include one or more of the following: phthalocyanine, porphyrin, naphthalene phthalocyanine, metal phthalocyanine, metal porphyrin, or metal naphthalene phthalocyanine. For example, the planar macrocyclic dye is zinc phthalocyanine.

[0013] The planar macrocyclic dye may be 0.002% to 0.5% by weight of the mixture of the polymer matrix, the liquid crystal, and the planar macrocyclic dye.

[0014] The modulator material layer can be an NCAP film. Alternatively, the modulator material layer can be a PDLC film, a palmitic liquid crystal film, a ferroelectric liquid crystal film, or a blue phase liquid crystal film.

[0015] When no electric field is present, the liquid crystal can be randomly oriented within the plurality of droplets. When an electric field is applied across the modulator material layer, the liquid crystal can be at least partially aligned along the direction of the electric field.

[0016] A method is provided in a third embodiment. The method comprises obtaining an emulsion by mixing water, liquid crystal, a planar macrocyclic dye, and a plurality of hydrophilic polymer molecules. The emulsion is coated onto a substrate. The emulsion is then dried. The emulsion forms a modulator material layer comprising: a polymer matrix formed of a plurality of cross-linked polymer molecules; a plurality of droplets of the liquid crystal within the polymer matrix; and the planar macrocyclic dye dispersed within the plurality of liquid crystal droplets. The planar macrocyclic dye may comprise one or more of the following: phthalocyanine, porphyrin, naphthyl phthalocyanine, metal phthalocyanine, metalloporphyrin, or metalnaphthalene phthalocyanine. Attached Figure Description

[0017] For a more complete understanding of the nature and purpose of this disclosure, reference should be made to the following detailed description taken in conjunction with the accompanying drawings, wherein:

[0018] Figure 1 This is a cross-sectional view of an optoelectronic modulator according to an embodiment of the present disclosure;

[0019] Figure 2 The diagram illustrates a view of a modulator material layer of an optoelectronic modulator according to an embodiment of the present disclosure, the material layer comprising droplets of liquid crystal, wherein planar macrocyclic dyes are dispersed within the droplets of liquid crystal;

[0020] Figure 3 It is a graph showing the experimental voltage transmittance curve;

[0021] Figure 4 A diagram illustrating the imaging system according to this disclosure; and

[0022] Figure 5 This is a flowchart of a method for manufacturing a photoelectric thin film according to an embodiment of the present disclosure. Detailed Implementation

[0023] While the claimed subject matter will be described with reference to specific embodiments, other embodiments (including those not providing all the benefits and features set forth herein) are also within the scope of this disclosure. Various structural, logical, process, and electronic changes may be made without departing from the scope of this disclosure. Therefore, the scope of this disclosure is defined only by the appended claims.

[0024] The embodiments disclosed herein use planar macrocyclic dyes to dope NCAP films or other films in optoelectronic modulators used in array inspector modulator technology to enhance the contrast ratio between off / on states in the film. Therefore, NCAP films or other films can be doped with planar macrocyclic dyes by dispersing the planar macrocyclic dye in liquid crystal droplets. This improves the signal-to-noise ratio (SNR) and enhances the modulator's sensitivity in detecting defects in flat panel displays. Thus, the detection capability of NCAP films or other films in array inspector modulator technology is improved by adding macrocyclic planar dyes. The optoelectronic modulator can be a component of an imaging system, also known as an automated optical inspection (AOI) system, a voltage imaging optical system (VIOS), an array inspector, or the like.

[0025] A method for manufacturing an optoelectronic modulator is also described. Embodiments of the optoelectronic modulator involve first coating a plastic sheet (e.g., Mylar) with a transparent conductive layer using an NCAP film or other thin film. A second plastic sheet (with or without a conductive layer) is then added. Next, this sandwich structure is laminated onto a glass substrate using an optical adhesive. Then, the top plastic sheet of the liquid crystal (LC) / polymer sandwich is peeled off and discarded. A dielectric mirror film (or pellicle) is formed on the plastic sheet and then added to the assembly stack.

[0026] U.S. Patent No. 7,817,333, filed February 6, 2007, entitled "Modulator with improved sensitivity and life time"; U.S. Patent No. 8,801,964, filed December 22, 2010, entitled "Encapsulated polymer networkliquid crystal material, device and applications"; and U.S. Patent No. 7,639,319, filed April 7, 2005, entitled "Polymer dispersed liquid crystal formulations for modulator fabrication," are each incorporated herein by reference in their entirety.

[0027] Figure 1This is a cross-sectional view of the photoelectric modulator 100. The photoelectric modulator 100 may include one or more thin films, layers, or coatings. The one or more thin film layers selectively allow light transmittance. For example, the photoelectric modulator 100 may include one or more of the following: a hard coating 102, a plastic film 104, a dielectric mirror film 106, a modulator material layer 108, a transparent conductive layer 110, a plastic film 112, an optical adhesive 114, a glass substrate 116, and / or an anti-reflective coating 118. Other thin films, layers, or coatings besides those described or illustrated with respect to the photoelectric modulator 100 are possible.

[0028] Modulator material layer 108 (also referred to as sensor layer, liquid crystal layer, polymer matrix layer, or similar) may be applied to glass substrate 116 by several methods, such as, but not limited to, direct coating or lamination. Embodiments using a lamination process involve first coating modulator material layer 108 with a plastic film 112 having a transparent conductive layer 110 (e.g., polyethylene terephthalate (PET), also referred to as Mylar). The transparent conductive layer 110 may generally comprise any material that is optically transparent and conductive for use as an electrode, such as, but not limited to, indium tin oxide (ITO) or another conductive material. Modulator material layer 108 may comprise a nematic alignment phase (NCAP) mixture, a polymer dispersed liquid crystal (PDLC) mixture, or other mixtures. Plastic film 112, and similarly, transparent conductive layer 110 and modulator material layer 108 may be laminated onto glass substrate 116 using optical adhesive 114. Dielectric mirror film 106 (or protective film) may be formed on plastic film 104 and then added to the assembled modulator material layer 108. In this embodiment, a vacuum-assisted attachment process is used. An anti-reflective coating 118 may be applied to the bottom surface of the glass substrate 116. Similarly, a hard coating 102 may be cured onto a plastic film 104. The hard coating 102 may comprise a main hard coating layer and a thinner slip agent layer.

[0029] The light transmission through the modulator material layer 108 can be varied depending on the magnitude of the electric field applied to the liquid crystal droplets in the modulator material layer 108. The transparent conductive layer 110 can be coupled to the sample capacitance to induce local voltages and electric fields. Local voltages can generate electric fields. The electric fields cause the liquid crystals in the modulator material layer 108 to align in the direction of the electric field.

[0030] Figure 2 This is a cross-sectional view of the modulator material layer 108. In one example, the modulator material layer 108 contains an NCAP mixture, but other mixtures are feasible. The modulator material layer 108 contains droplets 202 of liquid crystal suspended in a polymer matrix 204. The modulator material layer 108 contains a diluent of one or more materials, such as a planar macrocyclic dye 206 dispersed within the droplets 202. The planar macrocyclic dye 206 will be further described herein.

[0031] The NCAP used in the modulator material layer 108 comprises droplets 202. Each droplet 202 contains several types of liquid crystal molecules. The liquid crystal molecules exhibit a temperature transition within the liquid crystal phase. In some embodiments, the size of the droplet 202 is approximately one to five micrometers. The liquid crystal droplet may encompass a liquid crystal temperature range. A liquid crystal temperature range refers to the temperature at which the liquid crystal is in its liquid crystal phase (e.g., between the crystalline and liquid phases).

[0032] The liquid crystal droplets 202 may comprise any liquid crystal material. For example, the liquid crystal may comprise, but is not limited to, one or more of the following: nematic liquid crystals, polymer-dispersed liquid crystals, palmitic liquid crystals, ferroelectric liquid crystals, blue phase liquid crystals, mixtures of liquid crystals and dichroic dyes, cholesteric liquid crystals, or the like. The liquid crystal material may be generally hydrophobic, such that the liquid crystal droplets 202 can be formed together with the emulsion.

[0033] The modulator material layer 108 also includes a polymer matrix 204. The polymer matrix 204 may comprise any polymer matrix material. For example, the polymer matrix material may comprise, but is not limited to, one or more water-based polymers, such as polyvinyl alcohol (PVA), urethane (e.g., polyurethane), acrylate (e.g., polyacrylate, fluorinated acrylate, silicone acrylate), or water-based latex. A surfactant may be used to formulate the polymer matrix 204.

[0034] The amount of polymer matrix 204 material corresponds to the strength and stiffness of the sensor material. For example, the weight ratio of liquid crystal material to polymer matrix material can range from approximately 50 / 50 to approximately 80 / 20. Increasing the amount of polymer matrix 204 material can increase the strength and operating voltage of the sensor material.

[0035] A polymer matrix 204 is positioned around and contains the droplet 202. The droplet 202 is then dispersed within the polymer matrix 204. The droplet 202, containing liquid crystal molecules, can be anchored to the polymer matrix 204. In this embodiment, the degree of anchoring depends on the chemical properties of the liquid crystal molecules and the polymer matrix 204.

[0036] In the absence of an electric field, liquid crystal molecules can be randomly oriented within droplet 202. When an electric field is applied across modulator material layer 108, the liquid crystal can be at least partially aligned along the direction of the electric field. For this alignment to occur, the molecules overcome anchoring and / or friction with the polymer matrix 204 at the attachment sites. Subsequently, the orientation of the liquid crystal changes the transmittance of modulator material layer 108. For example, when no voltage is applied and the liquid crystal is randomly oriented, modulator material layer 108 can be opaque. When a voltage is applied and the liquid crystal molecules are at least partially aligned, modulator material layer 108 can be transparent or translucent. Thus, when the electric field is removed, the liquid crystal returns to random orientation.

[0037] The liquid crystal droplet 202 may contain a switching voltage. The inherent switching voltage of the liquid crystal may correspond to a voltage across the modulator material layer, at which light transmission through the photoelectric modulator has maximum sensitivity to voltage changes. In many embodiments, the switching voltage corresponds to the electric field strength at which approximately half of the liquid crystal molecules are aligned with the electric field. For optimal sensitivity, the goal is to invoke the maximum change in transmission with the minimum possible voltage change. Sensitivity can be improved by reducing the inherent switching voltage of the liquid crystal material. The operating voltage and sensitivity of the liquid crystal material may be related to one or more factors, such as, but not limited to, the properties of the liquid crystal, the properties of the polymer matrix, the size distribution of the liquid crystal droplets in the polymer matrix, and / or the interfacial properties between the polymer matrix and the liquid crystal.

[0038] Anchoring of liquid crystal molecules to the polymer matrix 204 can increase the inherent operating voltage of the modulator material layer 108. Frictional forces can include anchoring forces associated with static friction between the liquid crystal molecules and the polymer matrix, and can also include dynamic friction associated with the relative motion between the liquid crystal molecules and the polymer matrix. Since friction can affect the speed at which molecules move relative to the surrounding polymer matrix, reduced friction can increase the switching speed of the liquid crystal molecules. Since an increase in voltage may be required to overcome the anchoring of the liquid crystal molecules to the polymer matrix, increased anchoring can be associated with an increased inherent operating voltage of the modulator material layer 108. Therefore, the lower the frictional force and / or anchoring between the liquid crystal droplets 202 and the polymer matrix 204, the lower the driving voltage required to switch the liquid crystal molecules and / or the liquid crystal from a generally misaligned state to a state generally aligned with the electric field.

[0039] Planar macrocyclic dye 206 is dispersed within liquid crystal droplets 202. For example, planar macrocyclic dye 206 may comprise, consist of, or substantially consist of one or more of the following: phthalocyanine, porphyrin, or naphthalene phthalocyanine. For example, planar macrocyclic dye 206 may also comprise, consist of, or substantially consist of one or more metal analogs of these species (e.g., metal phthalocyanine, metal porphyrin, or metal naphthalene phthalocyanine).

[0040] Typically, metal phthalocyanines, metal porphyrins, or metal naphthalene phthalocyanines contain a metal with a charge of +2 or +3. The metal may include copper, zinc, platinum, iron, cobalt, or tin, but other metals may be used.

[0041] Phthalocyanines are aromatic organic compounds and can have a macrocyclic structure with the chemical formula (C8H4N2)4H2. Metal complexes of phthalocyanines form metal phthalocyanine compounds. Some examples of usable metal complexes of phthalocyanines are copper, cobalt, and zinc.

[0042] Examples of phthalocyanines that may be used according to this disclosure are presented below, but other phthalocyanines are also possible.

[0043]

[0044]

[0045]

[0046] In the example, the planar macrocyclic dye 206 is zinc phthalocyanine.

[0047] Porphyrins are heterocyclic macrocyclic organic compounds in which four modified pyrrole subunits are interconnected at their α-carbon atom via methylene bridges (=CH-). Porphyrins may also be bonded to metals. Porphyrins may contain different tails attached to an aromatic ring at the beginning. Examples of porphyrins that may be used according to this disclosure are presented below (protoporphyrin, IX, octaethylporphyrin, and tetraphenylporphyrin), but other porphyrins are possible.

[0048]

[0049]

[0050] Naphthalenephthalocyanine is a cruciform organic molecule with the chemical formula C2. 48 H 26 N8. It is a derivative of phthalocyanine. Exemplary derivatives are presented below, but other derivatives may be feasible.

[0051]

[0052] The use of planar macrocyclic dye 206 can enhance the optical contrast of materials in NCAP films, PDLC films, or other thin films. When embedded in liquid crystal droplets 202, planar macrocyclic dye 206 darkens the NCAP film or other thin film in the "off" state within a specific illumination wavelength range without significantly altering the transmittance in the on state, thus enhancing contrast. When implemented in optoelectronic modulators used in array inspector technology, planar macrocyclic dye 206 enhances the sensitivity of the modulator's NCAP film or other thin film to detect defects present in flat panel displays during panel manufacturing processes.

[0053] The planar macrocyclic dye 206 may have a weight percentage of 0.002 wt% to 0.5 wt% relative to the liquid crystal mixture comprising the polymer matrix, liquid crystal, and planar macrocyclic dye. For example, the weight percentage relative to the liquid crystal mixture may be 0.03%. The dye concentration may vary depending on solubility and chemical affinity with different liquid crystal materials. For example, the weight percentage may be 0.03 wt% to 0.1 wt% of the liquid crystal mixture to provide optimal solubility in the liquid crystal mixture. If the planar macrocyclic dye 206 has a weight percentage below 0.002 wt%, the contrast ratio between the off / on states in the film may not be enhanced. If the planar macrocyclic dye 206 has a weight percentage above 0.5 wt%, precipitation may occur.

[0054] Figure 3 It is a graph showing the experimental voltage transmittance curve. For example... Figure 3 As demonstrated, approximately 10% by weight of standard dichroic dyes are required to achieve the same performance as 0.03% by weight of zinc phthalocyanine.

[0055] Figure 4 This is a conceptual diagram illustrating imaging system 300. For the purposes of this disclosure, the term "imaging system" may be used interchangeably with the term "imaging tool." Imaging system 300 may generally include any type of imaging tool suitable for, for example, but not limited to, voltage imaging. Voltage imaging can be used to detect and measure defects in flat-panel thin-film transistor (TFT) arrays. The performance of the TFT array is simulated as if it were assembled into TFT cells, and then the characteristics of the TFT array are measured indirectly by measuring the actual voltage distribution on the panel, or so-called voltage imaging, using a photoelectric modulator (e.g., photoelectric modulator 100). Voltage imaging can be performed by imaging system 300. Imaging system 300 may include one or more components for inspecting these TFT arrays or other samples.

[0056] The photoelectric modulator 100 can be advantageous for several imaging tasks, such as modulating the light source of the imaging system 300 to assist in the detection of one or more defects in a sample 311 (e.g., but not limited to, a TFT array, a liquid crystal display (LCD) panel, an OLED panel, and the like). The TFT array can be formed on a substrate (e.g., a transparent thin glass plate). The TFT array can include one or more printed layers. The printed layers can be formed on the substrate by several processes, such as, but not limited to, one or more material deposition steps, one or more photolithography steps, one or more etching steps, or the like. Manufacturing can occur in stages, wherein materials (e.g., 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 fabricated within selected tolerances to correctly construct the final device. The printed layers may exhibit defects outside the selected tolerances. Defects can be detected by measuring the characteristics of the TFT array using the imaging system 300.

[0057] In an embodiment, the imaging system 300 includes an illumination source 306 for generating illumination 308. Illumination 308 may include light of one or more selected wavelengths, including, but not limited to, vacuum ultraviolet radiation (VUV), deep ultraviolet radiation (DUV), ultraviolet (UV) radiation, visible light radiation, or infrared (IR) radiation. Illumination source 306 may further generate illumination 308 encompassing any selected wavelength range. In an embodiment, illumination source 306 may include a spectrally tunable illumination source for generating illumination 308 having a tunable spectrum.

[0058] The illumination source 306 can guide the illumination 308 to the sample 311 via the illumination path 309. The illumination path 309 may include one or more lenses 312 or additional illumination optics 314 adapted to modify and / or adjust the illumination 308. For example, one or more illumination optics 314 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, photoelectric shutters, acousto-optic shutters, or the like), one or more aperture stops, and / or one or more field stops.

[0059] Imaging system 300 may include photoelectric modulator 100. Photoelectric modulator 100 is positioned in the path of illumination 308 from illumination source 306. Photoelectric modulator 100 can modulate one or more characteristics of illumination 308. During operation, light is transmitted through a portion of photoelectric modulator 100, and defects on or in sample 311 can be detected by observing changes in reflected or transmitted light. Photoelectric modulator 100 is separated from sample 311 by an air gap. Photoelectric modulator 100 may be positioned at a selected number of micrometers (e.g., between 5 micrometers and 75 micrometers) above the surface of sample 311 (e.g., a TFT array), and a voltage bias is applied across a transparent electrode of an indium tin oxide (ITO) layer on the surface of photoelectric modulator 100. Thus, photoelectric modulator 100 is capacitively coupled to sample 311, such that the electric field associated with sample 311 is sensed by one or more layers of photoelectric modulator 100 (e.g., a layer containing liquid crystal). The intensity of incident light transmitted through the liquid crystal through the photoelectric modulator is altered (i.e., modulated) based on the electric field strength sensed by the liquid crystal. For example, in regions where normal pixels are positioned, an applied local voltage potential (e.g., capacitive coupling between sample 311 and photoelectric modulator 100) causes one or more films of photoelectric modulator 100 to be partially translucent. In these partially translucent regions, light from light source 306 is allowed to pass through photoelectric modulator 100 and be reflected from sample 311 to travel through to light-collecting path 322 (e.g., to be captured by detector 304). By another example, in regions where no applied voltage potential is applied (e.g., no capacitive coupling), one or more films of photoelectric modulator 100 remain partially opaque. In cases where photoelectric modulator 100 is partially opaque, light from light source 306 is scattered or otherwise prevented from traveling through to sample 311. Therefore, the transmittance-voltage (TV) curve can be determined by applying a voltage. The inherent switching voltage of the photoelectric modulator 100 can correspond to a voltage across the photoelectric modulator 100 at which light transmission through the photoelectric modulator 100 is most sensitive to changes in voltage. For example, the switching voltage can correspond to an electric field strength at which a given percentage of liquid crystal molecules are substantially aligned with the electric field, allowing light transmission.

[0060] Sample 311 may include a TFT array. For example, sample 311 may include pixel elements disposed between non-active areas. Sample stage 318 may include any means suitable for positioning sample 311 within imaging system 300.

[0061] Detector 304 may be configured to capture radiation emitted from sample 311 (e.g., sample light 320) via light-collecting path 322. For example, light-collecting path 322 may include (but does not necessarily include) photoelectric modulator 100, light-collecting lens (e.g., objective lens), or one or more additional light-collecting path lenses 324. In this respect, detector 304 may receive radiation reflected or scattered from sample 311 (e.g., via specular reflection, diffuse reflection, and the like) or generated by sample 311 (e.g., emission associated with absorption by illumination 308, or the like).

[0062] System 300 may include, but is not limited to, controller 303. Controller 303 may include one or more processors and memory, and may include or be coupled to user interface 310.

[0063] The light-collecting path 322 may further include any number of light-collecting optical components 326 for guiding and / or modifying the illumination collected by the photoelectric modulator 100, including, but not limited to, one or more filters, one or more polarizers, or one or more baffles. Additionally, the light-collecting path 322 may include a field stop for controlling the spatial range of the sample image onto the detector 304, or an aperture stop for controlling the angular range of the illumination from the sample for generating an image on the detector 304. In another embodiment, the light-collecting path 322 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 imaging system 300 includes a beam splitter 328 oriented such that the photoelectric modulator 100 can simultaneously guide illumination 308 to the sample 311 and collect radiation emitted from the sample 311.

[0064] Detector 304 may comprise any type of optical detector suitable for measuring illumination received from sample 311. For example, detector 304 may comprise, but is not limited to, a charge-coupled device (CCD) detector, a time-delay integration (TDI) detector, a photomultiplier tube (PMT), an avalanche photodiode (APD), a complementary metal-oxide-semiconductor (CMOS) sensor, or the like. In another embodiment, detector 304 may comprise a spectral detector suitable for identifying the wavelength of light emitted from sample 311.

[0065] Controller 303 is communicatively coupled to detector 304. Controller 303 may include one or more processors configured to perform any of various process steps. In an embodiment, controller 303 is configured to generate and provide one or more control signals configured to perform one or more adjustments on one or more processing tools based on image signal 313 from detector 304.

[0066] One or more processors of controller 303 may comprise any processor or processing element known in the art. For the purposes of this disclosure, the terms “processor” or “processing element” may be broadly defined to encompass any means 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, one or more processors may comprise any means configured to execute algorithms and / or instructions (e.g., program instructions stored in memory). In one embodiment, one or more processors may embody a desktop computer, host computer system, workstation, image computer, parallel processor, networked computer, or any other computer system configured to execute programs (which are configured to operate or in conjunction with imaging system 300), as described throughout this disclosure. Furthermore, different subsystems of system 300 may include processors or logic elements suitable for performing at least a portion of the steps described in this disclosure. Therefore, the foregoing description should not be construed as limiting the embodiments of this disclosure but is merely illustrative. Furthermore, the steps described throughout this disclosure can be performed by a single controller or alternatively by multiple controllers. Additionally, controller 303 may comprise one or more controllers housed in a common housing or within multiple housings. In this manner, any controller or combination of controllers can be individually packaged as a module suitable for integration into imaging system 300. Furthermore, controller 303 can analyze data received from detector 304 and feed the data to additional components, either within or outside imaging system 300.

[0067] The memory medium may comprise any storage medium known in the art suitable for storing program instructions executable by one or more associated processors. For example, the memory medium may comprise non-transitory memory media. By another example, the memory medium may comprise, but is not limited to, read-only memory (ROM), random access memory (RAM), magnetic or optical storage devices (e.g., magnetic disks), magnetic tape, solid-state drives, and the like. It should further be noted that the memory medium may be housed together with one or more processors in a common controller housing. In one embodiment, the memory medium may be remotely located relative to the physical location of one or more processors and controller 303. For example, one or more processors of controller 303 may access remote memory (e.g., a server) accessible via a network (e.g., the Internet, an intranet, and the like).

[0068] User interface 310 is communicatively coupled to controller 303. User interface 310 may include, but is not limited to, one or more desktop computers, laptop computers, tablet computers, and the like. In embodiments, user interface 310 includes a display for displaying data from system 300 to a user. The display of user interface 310 may include any display known in the art. For example, the display may include, but is not limited to, a liquid crystal display (LCD), an organic light-emitting diode (OLED) based display, or a cathode ray tube (CRT) display. Those skilled in the art will recognize that any display device capable of being integrated with user interface 310 is suitable for implementation in this disclosure. In embodiments, a user may input selections and / or commands via user input devices of user interface 310 in response to data displayed to the user.

[0069] For reference Figure 5 The flowchart describes method 400. The method can also be referred to as a process for manufacturing an optoelectronic modulator. The embodiments and implementation techniques previously described herein in the context of optoelectronic modulator 100 and modulator material layer 108 should be interpreted as extensions of method 400. However, it should be further noted that the method is not limited to the architecture of optoelectronic modulator 100.

[0070] In step 410, water, surfactant, and defoamer are mixed to form a surfactant mixture. This step may include mixing for an extended duration (e.g., mixing overnight). The defoamer may contain silica / mineral oil (e.g., surface-treated silica) or the like.

[0071] In step 420, the mixture is mixed with liquid crystal and at least one planar macrocyclic dye 206. Mixing with the liquid crystal can be done via high-speed premixing and can be performed using heat. The mixture of liquid crystal and planar macrocyclic dye can be mixed with the solution prepared in step 410 at high speed or shear rate.

[0072] In step 430, the hydrophilic polymer aqueous emulsion is then mixed with the mixture to obtain an emulsion containing liquid crystal droplets. The hydrophilic polymer aqueous emulsion may contain hydrophilic polyurethane or the like. The electrical properties of the liquid crystal material can be improved by emulsifying the liquid crystal material. The liquid crystal can form small droplets dispersed within the polymer material. The size of the liquid crystal droplets ranges from 0.1 micrometers to 10 micrometers and may include an average size of 1 micrometer to 3 micrometers. When no electric field is applied, the liquid crystal molecules can be randomly oriented within the droplets. The liquid crystal / polymer material can be emulsified in any manner, such as, but not limited to, using the mechanical force of a high-speed blade. A crosslinking agent (e.g., polyaziridine or carbodiimide crosslinking agent) may be added in the range of 0.05% to 3%, followed by hand shaking to mix it into the emulsion.

[0073] In step 440, the emulsion is degassed. The emulsion is degassed under vacuum.

[0074] In step 450, an emulsion is coated onto a substrate. The substrate may comprise an ITO-coated PET Mylar. For example, the substrate may comprise a transparent conductive layer 110 and a plastic film 112. Many wet coating methods can be used. Examples include wire-wound coating, blade coating, slot die coating, extrusion coating, spin coating, spray coating, inkjet coating, etc.

[0075] In step 460, the emulsion is dried. The emulsion may be dried at room temperature for a first duration and at a high temperature (e.g., in an oven at 40°C) for a second duration. During drying, internal water is evaporated from the mixture. As the water evaporates, the liquid crystal droplets 202 remain dispersed within the polymer matrix 204, and the polymer matrix crosslinks. The dried emulsion forms a modulator material layer 108. The liquid crystal molecules can be anchored to the polymer matrix. The degree of anchoring depends on the liquid crystal molecules, the surfactant, and the polymer chemistry. When an electric field is applied across the liquid crystal material, the liquid crystal molecules and / or droplets can be at least partially aligned along the direction of the electric field. To enable this alignment, the liquid crystal molecules and / or droplets overcome anchoring and / or friction with the polymer at the attachment sites.

[0076] Upon further careful consideration, each of the embodiments of the methods described above may include any other steps of any other methods described herein.

[0077] Although planar macrocyclic dyes have been described as optoelectronic modulators added to imaging systems, this is not intended to be a limitation of this disclosure. Upon further careful consideration, planar macrocyclic dyes can be added to several water-based polymers. These water-based polymers can encompass several beneficial applications, such as smart window technology, sensors, or other NCAP liquid crystal films. In solvent-based systems, PDLC films, polymer-stabilized liquid crystals (PSLCs), polymer-stabilized cholesteric liquid crystals (PSCLCs), palmitic liquid crystals, ferroelectric liquid crystals, or blue phase liquid crystals can be similarly modified.

[0078] NCAP films are suitable for manufacturing very large-area light valves and displays. NCAP films are generally water-based and can be further subdivided into several subcategories. For example, subcategories of NCAP films include water-soluble polymers such as polyvinyl alcohol (PVA) or urethane. Due to their hydrophilic nature, water-soluble polymers are sensitive to moisture. Water-soluble polymer-based NCAP films can contain a two-phase material comprising liquid crystal and a water / polymer solution. By another example, subcategories of NCAP films include latex-based materials. Latex-based NCAP films can contain a three-phase material comprising water, liquid crystal, and a latex-based material. Latex-based materials contain insoluble polymers. Latex particles can be dispersed in water along with the liquid crystal. These latex particles can "fuse" into a continuous polymer phase that is irreversibly formed once the water is removed. Some applications using this latex-based NCAP exhibit long-term photoelectric stability. After drying, the liquid crystal is distributed within the polymer (latex or residual polymer (e.g., PVA)). Any of these NCAP films can benefit from the embodiments disclosed herein.

[0079] During the formation of modulator material layer 108, one or more surfactants (e.g., wetting agents) may be added to the aqueous mixture. The surfactants improve the stretchability of modulator material layer 108 by reducing surface tension.

[0080] As used throughout this disclosure, the term "sample" generally refers to a substrate formed of a semiconductor or non-semiconductor material (e.g., thin-film glass or the like). For example, semiconductor or non-semiconductor materials may include, but are not limited to, single-crystal silicon, gallium arsenide, indium phosphide, or glass materials. A sample may comprise one or more layers. For example, these layers may include, but are not limited to, resists (including photoresists), dielectric materials, conductive materials, and semiconducting materials. Many different types of these layers are known in the art, and the term "sample" as used herein is intended to cover all types of samples on which such layers can be formed. The one or more layers formed on the sample may be patterned or unpatterned. For example, a sample may comprise multiple dies, each having repeatably patterned features. The formation and processing of these material layers can ultimately result in a finished device. Many different types of devices can be formed on a sample, and the term "sample" as used herein is intended to cover samples on which any type of device known in the art is manufactured. Furthermore, for the purposes of this disclosure, the terms "sample" and "wafer" should be interpreted as interchangeable. Furthermore, for the purposes of this disclosure, the terms patterning device, mask, and photomask should be interpreted as interchangeable.

[0081] Although this disclosure has been described with respect to one or more specific embodiments, it will be understood that other embodiments of this disclosure may be made without departing from the scope of this disclosure. Therefore, this disclosure is to be considered limited only by the appended claims and their reasonable interpretation.

Claims

1. A modulator material layer comprising: A polymer matrix, which is formed by multiple cross-linked polymer molecules; Multiple droplets of liquid crystal within the polymer matrix; and Planar macrocyclic dyes are dispersed within the plurality of droplets of the liquid crystal. The liquid crystal droplets are anchored to the polymer matrix. When no electric field is present, the liquid crystal is randomly oriented within the plurality of droplets, and when an electric field is applied across the modulator material layer, the liquid crystal is at least partially aligned along the direction of the electric field.

2. The modulator material layer according to claim 1, wherein the planar macrocyclic dye comprises one or more of the following: phthalocyanine, porphyrin, naphthalene phthalocyanine, metal phthalocyanine, metal porphyrin, or metal naphthalene phthalocyanine.

3. The modulator material layer according to claim 2, wherein the planar macrocyclic dye comprises one or more of phthalocyanine, porphyrin, or naphthalene phthalocyanine.

4. The modulator material layer according to claim 2, wherein the planar macrocyclic dye comprises one or more of metal phthalocyanine, metal porphyrin, or metal naphthalene phthalocyanine.

5. The modulator material layer according to claim 2, wherein the planar macrocyclic dye is zinc phthalocyanine.

6. The modulator material layer according to claim 1, wherein the planar macrocyclic dye is 0.002% to 0.5% by weight of a mixture of the polymer matrix, the liquid crystal and the planar macrocyclic dye.

7. The modulator material layer according to claim 1, wherein the modulator material layer is a nematic curve aligned phase (NCAP) thin film.

8. The modulator material layer according to claim 1, wherein the modulator material layer is a polymer-dispersed liquid crystal (PDLC) film, a palmitic liquid crystal film, a ferroelectric liquid crystal film, or a blue phase liquid crystal film.

9. The modulator material layer of claim 1, wherein the size of the droplets is in the range of 0.1 micrometers to 10 micrometers.

10. The modulator material layer according to claim 1, further comprising a transparent conductive film disposed on the modulator material layer.

11. The modulator material layer of claim 1, further comprising a glass substrate, wherein the modulator material layer is one of a direct coating on the glass substrate or a stack on the glass substrate.

12. An imaging system comprising: A light source, configured to produce illumination; A stage configured to hold the sample; A detector used to generate an image of at least a portion of the sample; and A photoelectric modulator, disposed in the path of illumination from the illumination source and separated from the sample by an air gap, wherein the photoelectric modulator comprises: Transparent conductive film; A modulator material layer disposed on the transparent conductive film, the modulator material layer comprising: A polymer matrix, which is formed by multiple cross-linked polymer molecules; Multiple droplets of liquid crystal within the polymer matrix; and Planar macrocyclic dyes are dispersed within the plurality of droplets of the liquid crystal. The liquid crystal droplets are anchored to the polymer matrix. When no electric field is present, the liquid crystal is randomly oriented within the plurality of droplets, and when an electric field is applied across the modulator material layer, the liquid crystal is at least partially aligned along the direction of the electric field.

13. The imaging system of claim 12, wherein the planar macrocyclic dye comprises one or more of the following: phthalocyanine, porphyrin, naphthalene phthalocyanine, metal phthalocyanine, metal porphyrin, or metal naphthalene phthalocyanine.

14. The imaging system of claim 13, wherein the planar macrocyclic dye is zinc phthalocyanine.

15. The imaging system of claim 12, wherein the planar macrocyclic dye is 0.002% to 0.5% by weight of the mixture of the polymer matrix, the liquid crystal and the planar macrocyclic dye.

16. The imaging system of claim 12, wherein the modulator material layer is a nematic curve aligned phase (NCAP) thin film.

17. The imaging system according to claim 12, wherein the modulator material layer is a polymer-dispersed liquid crystal (PDLC) film, a palmitic liquid crystal film, a ferroelectric liquid crystal film, or a blue phase liquid crystal film.

18. A method comprising: An emulsion is obtained by mixing water, liquid crystal, planar macrocyclic dyes and multiple hydrophilic polymer molecules; The emulsion is coated onto the substrate; and The emulsion is dried, wherein the emulsion forms a modulator material layer, the modulator material layer comprising: A polymer matrix, which is formed by multiple cross-linked polymer molecules; The liquid crystal droplets are located within the polymer matrix; and The planar macrocyclic dye is dispersed within the plurality of droplets of the liquid crystal. The planar macrocyclic dyes described herein comprise one or more of the following: phthalocyanine, porphyrin, naphthalene phthalocyanine, metal phthalocyanine, metal porphyrin, or metal naphthalene phthalocyanine. The liquid crystal droplets are anchored to the polymer matrix. When no electric field is present, the liquid crystal is randomly oriented within the plurality of droplets, and when an electric field is applied across the modulator material layer, the liquid crystal is at least partially aligned along the direction of the electric field.

Images