Article comprising an optical element

Abstract

The invention relates to an article including an optical element. An article includes a substrate having a first surface and a second surface opposite the first surface; and an optical element on the first surface of the substrate, the optical element including an optical device region. The first surface of the substrate includes an outer region that extends a distance beyond a perimeter of the optic region. Methods of making the article and methods of cutting are also disclosed.

Description

[0001] Public domain

[0002] The present disclosure relates generally to articles such as optical devices and methods of making the same. background

[0004] Typically, when combining two layers of materials with different coefficients of thermal expansion (CTE) and / or when combining a layer of cross-linkable (polymer) material on top of a solid substrate material (such as glass), where the top layer shrinks during cross-linking, stress accumulates between the two material layers, resulting in bending of the layer stack. There are CTE differences between the layers, and temperature changes in device operation, as verified by thermal cycling testing, can lead to further stress enhancement and risk of substrate crack initiation / propagation, delamination, and / or cracking of the top layer. This can lead to reliability issues for articles such as optical devices or other devices that employ such layered stacks of materials.

[0005] What is needed is an article, such as an optical device, that reduces stress buildup between layers and / or improves device durability by utilizing novel designs and / or techniques for manufacturing such articles. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Features of the present disclosure are illustrated by way of example only and not limitation in the following figures, in which like numerals indicate like elements, wherein:

[0008] Figure 1 A schematic cross-sectional view of an optical device according to an aspect of the present disclosure is illustrated.

[0009] Figure 2 A schematic cross-sectional view of an optical device according to an aspect of the present disclosure is illustrated.

[0010] Figure 3 A schematic cross-sectional view of an optical device according to an aspect of the present disclosure is illustrated.

[0011] Figure 4 A schematic cross-sectional view of an optical device according to an aspect of the present disclosure is illustrated.

[0012] Figure 5 A schematic cross-sectional view of an optical device according to an aspect of the present disclosure is illustrated.

[0013] Figure 6 A schematic cross-sectional view of an optical device according to an aspect of the present disclosure is illustrated.

[0014] Figure 7 A schematic cross-sectional view of an optical device according to an aspect of the present disclosure is illustrated.

[0015] FIG. 8A to FIG. 8CA method of manufacturing an optical device according to an aspect of the present disclosure is illustrated.

[0016] Fig. 9A A top view of an optical device according to an example of the present disclosure is shown.

[0017] Fig. 9B A top view of an optical device according to a comparative example is shown.

[0018] Overview

[0019] In one aspect, an article is disclosed. The article includes a substrate having a first surface and a second surface opposite the first surface; and an optical element on the first surface of the substrate, the optical element including an optics region. The first surface of the substrate includes an outer region that extends a certain distance beyond the perimeter of the optics region.

[0020] In another aspect, a method of manufacturing a plurality of articles on a substrate is disclosed. The method includes: depositing a layer on a first surface of the substrate for forming a plurality of optical device regions, each optical device region corresponding to one of the plurality of articles; and thinning a portion of the layer to form a thinned region between the plurality of optical device regions.

[0021] In yet another aspect, a method of singulating is disclosed. The method includes thinning a portion of a layer to form a thinned region between a plurality of device regions on a substrate; and severing the substrate in the thinned region to form singulated devices.

[0022] The additional features and advantages of various embodiments will be explained in part in the following description, and will be partially obvious from the description, or can be learned through the practice of various embodiments. The purposes and other advantages of various embodiments will be realized and obtained by means of the elements and combinations particularly pointed out in the description of this article. Detailed Description

[0024] For simplicity and illustrative purposes, the present disclosure is described primarily by reference to its examples. In the following description, many specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be apparent that the present disclosure can be implemented without limiting these specific details. In other cases, some methods and structures have not yet been described in detail in order to avoid unnecessarily obscuring the present disclosure.

[0025] Additionally, the elements depicted in the drawings may include additional components and some of the components depicted in those drawings may be removed and / or modified without departing from the scope of the present disclosure. Furthermore, the elements depicted in the drawings may not be drawn to scale, and therefore, the elements may have sizes and / or configurations different from those shown in the drawings.

[0026] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are intended to provide explanation of various embodiments of the present teachings.

[0027] The present disclosure relates to an article (such as an optical device) that includes an optical element (e.g., a light shaping optical element (LSOE)) that includes a functional edge having certain advantages. For example, the advantages may include one or more of the following: allowing a wider selection of materials for the optical element; protecting the optical element from delamination on a substrate; reducing the risk of cracking within the optical element; improving the reliability of the optical device without affecting the optical performance; improving the reliability of the optical device in a package without affecting the optical performance; reducing stress caused by cross-linking shrinkage of the polymer of the optical element; reducing stress caused by thermal expansion mismatch between the optical element and the substrate; allowing the use of high T with high modulus g Materials are used for optical components; allow the use of high cross-link density materials for optical components; reduce edge damage at substrates and optical components; reduce moisture ingress points at the periphery of substrates and optical components in humid environments.

[0028] In its broad and various embodiments, an article, such as an optical device 10, is disclosed herein. The optical device 10 includes a substrate 12 having a first surface and a second surface opposite the first surface. An optical element 14 is on the first surface of the substrate 12. The optical element 14 includes an optical device region 16. The first surface of the substrate 12 includes an outer region 18 that extends beyond a perimeter 20 of the optical device region 16 by a distance C, such as Figure 1 shown. Figure 1 The optical device 10 may be a singulated optical device (eg, an optical device cut or separated from a larger source substrate), as will be described in greater detail below.

[0029] In one aspect, the optical element 14 further includes an edge region 22 on the outer region 18 of the substrate 12. The edge region 22 extends partially or completely around the perimeter 20 of the optical device region 16. The edge region 22 has an edge thickness B that is less than the thickness A, which can be the total thickness of the optical device region 16. As an example, the ratio of the edge thickness B to the optical element thickness A is in the range of about 0 to about 0.95, such as about 0.01 to about 0.5, about 0.05 to about 0.2, or about 0.5 to about 0.1. The selected thickness B can depend on the width of the edge region 22 and the material used, etc. As an example, the edge thickness B can be in the range of 0 (i.e., no optical element material on the outer region 18) to about 100 microns, such as about 0.01 microns to about 30 microns, or about 0.1 microns to about 10 microns, or about 1 micron to about 8 microns. In one aspect, edge thickness B is substantially or completely uniform across edge width C, wherein the term "substantially" allows for a thickness variation of about 15% relative to the thickness of the outermost edge of edge region 22. In an example, edge thickness B has a thickness variation of 10% or less relative to the thickness of the outermost edge of edge region 22.

[0030] The introduction of a functional edge (e.g., edge region 22), including the variations described below, can reduce and shift the maximum stress toward the interior of the device away from the outer dimensions and corners of the optical device, where the stress maximum would otherwise be located. This can reduce the overall stress load on the optical device during singulation of the source substrate (e.g., wafer) into the final substrate size (e.g., die) and in the packaged optical device, thereby reducing defects that occur in real-world operation as simulated by accelerated thermal cycling testing.

[0031] The functional edge can enable the manufacture and use of articles such as optical devices (e.g., such as any optical device described herein) that would otherwise not meet electronic and automotive (AEC) test specifications, such as: for example, 1000 cycle tests, such as -40°C to 85°C thermal cycling and -40°C to 125°C AEC power temperature cycling tests according to MIL STD 883H Method 1010.8; and / or 85°C / 85% RH (relative humidity) 1000 hour testing.

[0032] In one aspect, substrate 12 includes a first material having a first coefficient of thermal expansion ("CTE"), and optical element 14 includes a second material having a second CTE, wherein the first CTE is different from the second CTE. For example, the difference between the first CTE and the second CTE can be in a range of 0.1 ppm / K to 100 ppm / K, such as, for example, about 1 ppm / K to about 20 ppm / K, or about 5 ppm / K to about 10 ppm / K.

[0033] The substrate may include any suitable material that is transparent, provides adequate structural support for the optical elements, and is transparent in the wavelengths of radiation with which the optical device 10 is intended to be employed, such as one or more of the ultraviolet, visible, and infrared wavelengths (e.g., wavelengths in the range of 200 nm to 3000 nm). In one aspect, a suitable material may be an organic or inorganic transparent material having a CTE in the range of 0.5 ppm / K to 100 ppm / K. Examples of suitable materials include glass, such as borosilicate glass, alkaline or non-alkali glass (e.g., alkaline or non-alkali borosilicate glass), and metal oxide glass; silicon, hydrogenated silicon, germanium, and transparent polymers.

[0034] The substrate 12 of the optical device can have any suitable thickness S and width W. Additionally, the ratio of the thickness A of the optical element 14 to the total thickness A+S of the optical device 10 is in the range of about 0.001 to about 1, such as about 0.01 to about 0.8 or about 0.1 to about 0.5. Additionally, the ratio of the edge width C to the total width W of the substrate 12 is in the range of about 0.001 to about 0.999, such as 0.01 to about 0.5, such as about 0.05 to about 0.2.

[0035] Optical element 14 may include any optically transparent organic or inorganic optical element material. The term "optically transparent" refers to being transparent in the wavelength of radiation with which the optical device is intended to be employed, such as one or more of the ultraviolet, visible, and infrared wavelengths (e.g., wavelengths in the range of 200 nm to 3000 nm). The optical element material may optionally serve as a matrix that includes at least one additional optical material within its volume. The material used for optical element 14 may be formed and / or take a shape that includes a surface profile, such as surface profile 60 of optical device 10, such as Figure 7 The diffuser shown in , or any other desired surface profile 60 that provides the desired optical function.

[0036] For example, the material of the optical element 14 can be any curable polymer. Non-limiting examples of suitable optical element materials include thermoplastics such as polyesters, polyolefins, polycarbonates, polyamides, polyimides, polyurethanes, acrylics, acrylates, polyvinyl esters, polyethers, polythiols, silicones, fluorocarbons, and their various copolymers; thermosetting materials such as epoxies, polyurethanes, acrylates, melamine formaldehyde, urea formaldehyde, and phenol formaldehyde; energy curable materials such as acrylates, epoxies, vinyls, vinyl esters, styrenes, and silanes; and combinations thereof. Additional optical element materials include, but are not limited to, silanes, siloxanes, titanates, zirconates, aluminates, silicates, phosphazenes, polyborazylene, and polysulfur nitride.

[0037] In one aspect, the polymer chains of the material of the optical element 14 can be cross-linked using a polymerization technique to cure the polymer. Non-limiting examples of polymerization techniques include photoinduced polymerization, such as free radical polymerization, spectral sensitized photoinduced free radical polymerization, photoinduced cationic polymerization, spectral sensitized photoinduced cationic polymerization, and photoinduced cycloaddition; electron beam induced polymerization, such as electron beam induced free radical polymerization, electron beam induced cationic polymerization, and electron beam induced cycloaddition; and thermal induced polymerization, such as thermal induced cationic polymerization. In one aspect, the material of the optical element 14 can be deposited on the substrate 12 or formed in a mold with a negative surface profile and then cross-linked and / or cured using techniques such as non-free radical curing systems, ultraviolet light, visible light, infrared light, heat, chemical induction, and / or electron beam.

[0038] Additional optical materials can provide optical functions that cannot be provided by the optical element material or surface profile alone. Non-limiting examples of properties include, but are not limited to, light scattering, electrical and / or magnetic properties, fluorescent properties, IR to visible light conversion properties (low energy incident light produces higher energy), electrochromism, thermochromism, wavelength-dependent absorption, thin film interferometry, diffraction interferometry, polarization control, and combinations thereof.

[0039] At least one additional optical material can exist in an organic phase, an inorganic phase, or a gas phase. At least one additional optical material can be in the form of particles (nanoparticles or microparticles), rods, wires, fibers, silk, ribbons, ellipses, other shapes, and combinations thereof. On the one hand, at least one additional optical material can be a combination of particles, wherein the particle size is in the range of about 20nm to about 1000nm, for example, about 30nm to about 900nm, and as a further example, about 40nm to about 800nm. On the one hand, at least one additional optical material can be present in the optical element material as embedded particles (randomly or specifically placed) within the volume of the optical element material, as a particle layer within the optical element material, or as particles on the surface profile 60 of the optical element material.

[0040] At least one additional optical material can be a metallic material. Non-limiting examples of metallic materials include aluminum, palladium, silver, titanium, iron, cobalt, copper, tin, gold, nickel, alloys thereof; metal compounds involving carbon, oxygen, nitrogen, and combinations thereof; and combinations thereof.

[0041] At least one additional optical material can be an inorganic non-metallic material. Non-limiting examples of suitable inorganic non-metallic materials include metal oxides such as SiO2, TiO2, Al2O3, ZrO2, WO3, VO5, ITO, Ta2O5, CeO2, Y2O3, ZnS, ZnO, In2O3, La2O3, MgO, Nd2O3, Pr6O 11 , Fe2O3, Fe3O4, SiO, SnO and FeO x ; Metal fluorides such as MgF2, AlF3, CeF3, LaF3, LiF and CaF2; Cermets, diamond-like carbon and combinations thereof. When used in non-stoichiometric compounds, metal oxides can be represented as MOx, where M is a metal, O is oxygen, and x can be a fraction.

[0042] At least one additional optical material can be an absorbing material capable of acting as a uniform or selective absorber at different wavelengths. Non-limiting examples of absorbing materials include carbon, graphite, silicon, germanium, cermets, metals mixed in a dielectric matrix, Inconel, stainless steel, hastelloy, and combinations thereof.

[0043] At least one additional optical material may be an organic colored material. Non-limiting examples of organic colored materials include perylene, perinone, quinacridone, quinacridonequinone, anthrapyrimidine, anthraquinone, anthranthrone, benzimidazolone, disazo condensation, azo, quinolone, xanthene, azomethine, quinophthalone, indanthrone, phthalocyanine, triarylcarbonium, dioxazine, aminoanthraquinone, isoindoline, diketopyrrolopyrrole, thioindigo, thiazine indigo, isoindolinone, pyranthrone, isoanthrone violet, miyoshimethane, triarylmethane, and mixtures thereof.

[0044] At least one additional optical material can be a liquid crystal polymer. Liquid crystal polymer (LCP) can be one or more cured polymer liquid crystal components. LCP can have a color depending on the viewing angle, and can be composed of an oriented three-dimensional cross-linked substance with a liquid crystal structure having a chiral phase. The LCP structure can be obtained by orienting one or more three-dimensional cross-linkable liquid crystal substances with a chiral phase, then three-dimensionally cross-linking, and then crushing to a desired particle size. The obtained LCP structure is a platelet-like particle (i.e., a polymer or monomer fluid before cross-linking is in an ordered state of a liquid crystal type) of a cross-linked substance including a liquid crystal structure. Alternatively, the LCP structure can be formed by coating the platelet-like particles with a liquid crystal material. The LCP structure can be made of a precursor composition including at least one nematic compound and at least one chiral dopant compound.

[0045] against Figure 1 and Figure 7 The dimensions and materials taught in the optical device of can be applied to any optical device described herein. For example, for A, B, C, S, W and F (where F is Figure 7 and discussed below), the materials for substrate 12 and optical element 14, and the methods of making these layers, such as for Figure 1 and Figure 7 The teachings of the optical devices shown in can be applied to any optical device described herein.

[0046] Optical element 14 can be attached to substrate 12 in any suitable manner. Figure 4 As shown, the optical element 14 is bonded to the substrate 12 by bonding features 40 and 42, which are respectively disposed between the edge region 22 and the substrate 12 and between the optical device region 16 and the substrate 12. In one aspect, the bonding feature 40 between the edge region 22 and the substrate 12 is enhanced (i.e., provides a stronger bond) compared to the bonding feature 42 between the optical device region 16 and the substrate 12. In another aspect, both the bonding feature 40 and the bonding feature 42 are enhanced so as to provide the same or similar bonding strength. In one aspect, the ratio of the area of ​​the bonding feature (e.g., the total area of ​​the bonding feature 40 and / or the bonding feature 42) to the surface area of ​​the first surface of the substrate 12 is in the range of about 0.001 to about 1, such as about 0.01 to about 0.8, or about 0.1 to about 0.5. The bonding feature in the substrate region between the edge region 22 and the substrate 12 can improve reliability by preventing early delamination of the outer periphery of the optical element 14 (e.g., LSOE). The bonding features may be formed by increasing the local roughness of the surface of the substrate 12 on a nanometer and micrometer scale prior to depositing the optical element 14 by, for example, physical, chemical, or mechanical methods, and / or by increasing the number of chemical bonds at the interface between the substrate 12 and the edge region 22 of the optical element 14. In an example, one or both of the regions 40 and 42 of the substrate 12 have a surface roughness sufficient to enhance adhesion. For example, the surface roughness may be in the range of about 0.001 μm to about 5 μm, such as about 0.1 μm to about 3 μm, or about 0.5 μm to about 2 μm. Any optical device 10 described herein may include one or both of the bonding features 40 and 42 as described herein.

[0047] refer to Figure 5 , the optical device 10 can be optionally attached to a packaging 70 (e.g., enclosed in or secured to the packaging 70). The packaging 70 can be in the form of a subassembly structure and / or one or more protective layers, as is known in the art. Figure 54 is shown as a roughened area on the outer surface 44 of the optical element 14 in FIG. The bonding feature can be formed by increasing the surface roughness on the outer surface 44 compared to the same surface before the bonding feature is formed. For example, the increased surface roughness can be in the range of about 0.001 μm to about 5 μm, such as about 0.1 μm to about 3 μm, or about 0.5 μm to about 2 μm. Such bonding features can further improve the bonding of the optical device 10 to the device package 70 and / or improve reliability compared to devices without such bonding features formed. The bonding feature can be provided by physical, chemical, and mechanical methods of increasing local roughness and / or by increasing the number of chemical bonds to the device package 70 on the top surface of the edge region 22. Any optical device 10 described herein may include such a bonding feature so as to provide a bonding feature similar to that for Figure 5 The device enhances adhesion to the package 70 in the manner described.

[0048] In one aspect, as described above, the optical device 10 is a diffuser or other device having a non-uniform thickness in the optical device region 16. The diffuser or other device can be any of the materials of the optical element 14 and / or the materials of the substrate 12 described herein. The optical element 14 can include: a bottom surface (such as a flat surface) that can be bonded to the first surface of the substrate 12; and a surface having a surface profile 60, such as Figure 7 . Surface profile 60 can be any profile that will provide the desired functionality (e.g., a diffuser profile and / or a light shaping profile), and can be in the form of, for example, a random surface profile, a periodic surface profile, a patterned surface profile, or a combination of these profiles. Surface profile 60 can be produced by methods such as stamping, embossing, molding, or reactive ion etching, as is known in the art. In aspects where optical device 10 is a diffuser or other device in which optical device region 16 has a non-uniform thickness, optical device region 16 can have a base layer thickness F that is less than the total thickness A of optical device region 16. The base layer is the thickness of the optical device region 16 between substrate 12 and an imaginary plane (in the plane of the optical device region 16). Figure 7 The imaginary plane is parallel to the first surface of the substrate 12 and is adjacent to the surface of the profile 60 that is closest to the first surface of the substrate 12. For example, the ratio of the edge thickness B to the base thickness F is in the range of about 0 to about 0.95. As another example, the value of the ratio B:F can be the same as disclosed herein. Figure 1 For any value of the thickness ratio B:A, it will be appreciated that in the case where the optical device region 16 has a diffuser or other device of non-uniform thickness, the total thickness A can generally be greater than the thickness F of the base layer.

[0049] As described herein, introducing the edge region 22 protects an article (such as any optical element described herein) from damage by reducing stress within the optical device 10. The thickness ratio B / A and width C can be selected to allow adjustment of the stress distribution at the interface of the optical element and the substrate. Depending on the substrate thickness S, stress caused by the material mismatch between the optical element 14 and the substrate 12 can be effectively reduced to allow a wider range of processing and handling. Similarly, with respect to Figure 7 , the optical element 14 having a total thickness of A and a thickness ratio of F / A can be protected by specifically selecting the ratio B / F (where B < F) and width C to allow adjustment of the stress distribution at the interface of the optical element 14 and the substrate 12.

[0050] Reference Figure 2 and Figure 3 , any optical device 10 described herein can include a transition region D, E, or R between the edge region 22 and the optical device region 16, where the transition region D or E can include at least one sidewall 30 having an angle θ, and the transition region R can include a radially curved surface 34. As Figure 2 shown, the sidewall 30 can be angled with respect to the plane 32 of the edge region 22. For example, the sidewall 30 can have an angle θ with the plane 32 in the range of about 5 degrees to about 175 degrees. Figure 2 An obtuse angle θ1 (on the left side of the optical device region 16) and an acute angle θ2 (on the right side of the optical device region 16) are shown. However, if desired, the entire edge region 22 can have one or the other of an acute or obtuse angle (e.g., θ can be the same for the entire edge region). Alternatively, as needed, any portion of the edge region 22 can be an obtuse angle θ, an acute angle θ, or a 90° angle θ. Compared to the optical device of Figure 1 (in the case where the optical element 14 has a uniform thickness, such as in Figure 1 ), employing the transition region D or E between the edge region 22 and the total thickness A of the optical element 14 or (in the case where the optical element has a non-uniform thickness, such as in Figure 7 ) between the edge region 22 and the base thickness F of the optical element 14 can move the stress maximum further away from the substrate edge, thereby reducing the risk of cracking at the edge. Any optical device 10 described herein can have a transition region D or E that includes a sidewall 30 having an angle θ, the range of which is as described herein for Figure 2 .

[0051] As Figure 3As shown, transition region R may include a radially curved surface 34 between edge region 22 and sidewall 30 of optical device region 16. The radius r1 of curved surface 34 may be constant or variable (e.g., changing from the beginning to the end of the transition). Figure 1 ) or thickness F( Figure 7 ) can be achieved by using a sharp edge (such as, respectively, Figure 1 and Figure 2 The 90 degree angle or other angle θ seen in FIG. 1 can be used to reduce or minimize the stress peak to additionally reduce stress, and thereby reduce stress compared to Figure 1 and / or Figure 2 The structure can provide further stress distribution. Any value of r1 that provides the desired stress reduction effect can be adopted. The value of r1 can be, for example, in the range of about 1 micron to about 100 microns. Any optical device 10 described herein may include a transition region R that includes a radially curved surface 34.

[0052] like Figure 6 As shown, the optical device 10 may further include an optical stack 50, which is composed of one or more layers on the second surface of the substrate 12. The optical stack 50 may include one or more layers of any suitable material, including layers selected from optical filters, anti-reflection layers, light coupling layers, and stress reduction layers. The techniques for making and using such layers to form optical stacks are well known. In one aspect, the optical stack may include a single layer or multiple layers of the same material as the optical element 14, such as any material described herein for the optical element 14. For example, the optical stack 50 may be a single flat layer without structure. The thickness ratio of the thickness D of the optical stack 50 to the thickness A of the LSOE optical device region 16 may be any suitable thickness ratio that will provide the desired optical and mechanical functions (such as, for example, wavelength filtering and / or stress balancing). For example, such a thickness ratio D:A may be in the range of about 0.1 to about 1.

[0053] The optical stack 50 on the second surface (e.g., backside) of the substrate 12 can further reduce bending of the article due to stress caused by cross-linking and / or thermal mismatch (e.g., between the LSOE optical element 14 and the substrate 12). Reducing stress-induced bending can further reduce the risk of cracking and / or delamination of the optical device 10 compared to a device made without the optical stack 50. Any optical device 10 described herein can include an optical stack 50.

[0054] The present disclosure also relates to a method of manufacturing a plurality of articles on a substrate. FIG. 8A to FIG. 8CThe method includes depositing a layer on a first surface of a substrate for forming a plurality of optical device regions, each optical device region corresponding to one of a plurality of articles. Substrate 100 may include any material disclosed herein for substrate 12. Layer 102 may include any material described herein for optical element 14. In one aspect, layer 102 may be an optically transparent material.

[0055] In one aspect, layer 102 has a uniform thickness T, which can be any desired thickness. For example, T can be in the range of about 10 microns to about 200 microns. Prior to depositing layer 102, an adhesion treatment can optionally be performed by increasing the local roughness of region 40 (not shown in dashed lines) and / or region 42 (shown in dashed lines) of source substrate 100 on a nanoscale, for example, by physical, chemical, or mechanical methods, and / or by increasing the number of chemical bonds at the interface between source substrate 100 and edge region 22 of optical element 14.

[0056] refer to Figure 8B , further processing may optionally be performed to form a surface profile 60 of a plurality of optical device regions 16 in layer 102. Optical device regions 16 may have a thickness and optical function and may be the same as any of the optical device regions described herein. Without further processing, the optical device regions 16 of the finished device may include a uniform thickness A ( Figure 1 ), the uniform thickness A is equal to the thickness T of layer 102.

[0057] refer to Figure 8C , the method further includes thinning a portion of layer 102 to form a thinned region 104 between the plurality of optical device regions. Thinning may remove all or a portion of layer 102 in thinned region 104. Thinning may be performed by any suitable technique for removing material of layer 102, such as, for example, mechanically cutting a channel (e.g., using a blade such as a saw blade or other mechanical device), laser removal, chemical etching, applying a mold prior to curing, or a combination of such techniques.

[0058] In one aspect, where the material of layer 102 comprises a polymer, the polymer chains of the optical element material may be cross-linked using a polymerization technique to cure the polymer. Cross-linking and curing may occur at any desired time during fabrication of the optical element, such as after forming the surface profile 60 of the optical device region (which surface profile 60 may first be formed by applying a mold to the uncured material of layer 102 to provide the desired surface profile). In one aspect, a mold may also be applied to form the thinned region 104. This may occur at a different time than forming the surface profile 60, such as at a later time. Figure 8B and Figure 8CAlternatively, a mold may be used to form the thinned region 104 simultaneously with the surface profile 60 of the optic region. Cross-linking and curing may occur simultaneously with or after molding of the surface profile and / or the thinned region.

[0059] Non-limiting examples of polymerization techniques include photoinduced polymerization, such as free radical polymerization, spectral sensitized photoinduced free radical polymerization, photoinduced cationic polymerization, spectral sensitized photoinduced cationic polymerization, and photoinduced cycloaddition; electron beam induced polymerization, such as electron beam induced free radical polymerization, electron beam induced cationic polymerization, and electron beam induced cycloaddition; and thermal induced polymerization, such as thermal induced cationic polymerization. In one aspect, the material of layer 102 can be deposited on substrate 12 or formed in a mold having a negative surface profile, and then crosslinked and / or cured using techniques such as non-free radical curing systems, ultraviolet light, visible light, infrared light, heat, chemical induction, and / or electron beam.

[0060] According to one aspect of the present disclosure, the thinned region 104 may include an outer surface (eg, corresponding to Figure 5 The outer surface 44 of the edge region 22 of the optical device is treated to provide a desired surface roughness sufficient to enhance adhesion to a package to which the optical device may subsequently be attached. For example, the surface roughness can be in the range of about 0.025 μm to about 500 μm. Adhesion enhancement can be provided by increasing the local roughness by physical, chemical, and mechanical methods and / or by increasing the number of chemical bonds on the thinned region 104. The surface of the thinned region can be roughened using any suitable method, such as by contacting the surface with a blade (e.g., a saw blade) or other abrasive device. The benefit of using a mechanical blade to thin the edge region 22 is that the surface can be roughened simultaneously as the optical element material is removed. The blade used can be selected to provide the desired roughness.

[0061] After thinning, the method may further include severing the source substrate 100 and any remaining portions of the layer 102 in the thinned region 104 to form a singulated optical device 10, such as Figures 1 to 7 For example, the cut-off can occur at Figure 8C10. The cutting may be performed by any suitable technique, such as a dicing technique, examples of which are well known in the art. The width of the material removed during the cutting process is less than the width of the thinned region, so as to provide an edge region 22 in the singulated optical device 10. Thus, as described herein, each singulated optical device 10 includes an outer region of the substrate that extends a distance beyond the perimeter of the optical device region, i.e., an edge width C. The edge region 22 may extend partially or completely around the perimeter of the optical device region 16 of the singulated optical device 10. The edge region 22 has an edge thickness B that is less than the thickness A of the optical device region 16. The dimensions (e.g., A, B, C, S, W, F, and θ), materials, and methods of manufacturing these layers employed for the substrate 12 and optical element 14 may be the same as those taught for any optical device described herein.

[0062] In one aspect, the monomerized optical device 10 described herein has reduced material mismatch stress between the optical element 14 and the substrate 12 compared to a second optical device that: i) has a substrate of the same size as the first optical device, and ii) is otherwise identical to the first optical device except that the optical element does not include an edge region 22 as described herein, in which the optical element has been thinned or completely removed from the substrate between multiple optical device regions.

[0063] The present disclosure also relates to a wafer comprising a source substrate 100 and a layer 102 comprising a thinned region 104 and a plurality of optical device regions 16, such as, for example Figure 8C 10 (before singulation). Thus, the wafer may include a plurality of optical devices 10 that have not yet been singulated and are optionally attached to a package 70. The thickness of the thinned region 104 may be the same as the thickness B of the edge region 22, and the width of the thinned region 104 between the optical device regions 16 may be at least twice the width C of the edge region 22, wherein the dimensions of the optical device 10 (e.g., the dimensions of A, B, C, S, W, F, T, and θ) may be the same as described for any optical device, source substrate 100, or layer 102 herein. The substrate 100 may include any material disclosed herein for the substrate 12. The layer 102 may include any material described herein for the optical element 14. The optical device region 16 may be the same as any optical device 10 described herein.

[0064] One aspect of the present disclosure relates to a method of singulation. The singulation method described herein can be used to singulate optical devices as shown herein, as well as for other devices formed integrally on a substrate. The method includes: thinning a portion of a layer on a substrate to form a thinned region between multiple device regions on the substrate; and cutting the substrate in the thinned region to form a singulated device. The layer may have a coefficient of thermal expansion (CTE) different from that of the substrate, such as a CTE difference within a range as described herein. The layer may include any organic or inorganic material. In one aspect, the layer may include any material described herein for optical element 14. For example, the layer includes a cross-linked polymer material. The substrate may include any organic or inorganic material. In one aspect, the substrate may include any material described herein for substrate 12. For example, the device region may include an optical element as described herein or any other device. Thinning and cutting can be performed by any thinning or cutting method described herein. Thinning and cutting can produce an outer region, such as an edge region, that extends partially or completely around the periphery of a device region (e.g., an optical device region as described herein). The outer region and edge region can be similar to those described herein with respect to Figures 1 to 7 100, including having the same width, thickness or other dimensions, transition regions (such as sidewalls or radially curved surfaces), and surface roughness as disclosed herein. For example, the thickness of the thinned region can be the same as the thickness B of the edge region 22 as described herein, and the width of the thinned region between device regions can be at least twice the width C of the edge region 22 before singulation. The dimensions of the resulting singulated device (e.g., the dimensions of A, B, C, S, W, F, T, and θ) can be the same as those described herein for any of the optical devices, source substrate 100, or layer 102. Also contemplated are singulated devices made by the singulation methods described herein.

[0065] Example

[0066] Example 1: Power Thermal Cycling

[0067] The power thermal cycling test was performed on an optical device 10, which includes a substrate and an optical element on a first surface of the substrate. The optical element includes an edge region 22 on an outer region of the substrate, which extends completely around the perimeter of the optical device region (at Fig. 9A 10, shown as a lighter area around the perimeter of the rectangular device). The edge region has an edge thickness less than the thickness of the optical device region and a width of approximately 100 microns. AEC power temperature cycling test from -40°C to 125°C was performed on the optical device 10. After the optical element passed 1000 cycles, it was shown that the optical element did not delaminate from the substrate.

[0068] Comparative Example: Power Thermal Cycling

[0069] Power thermal cycling testing was performed on an optic similar to that of Example 1 except that the edge region was not included on the outer region of the substrate. AEC power temperature cycling testing from -40°C to 125°C was performed on the comparative optic. The optic failed after 200 cycles, showing areas of delamination (at Fig. 9B , shown as a lighter area around the entire perimeter on all four sides). Fig. 9B In the 3D image above, an internal glass crack is visible in the larger delamination area shown near the lower left corner of the device.

[0070] One aspect of the present disclosure relates to an article comprising: a substrate having a first surface and a second surface opposite the first surface; and an optical element on the first surface of the substrate, the optical element comprising an optical device region; wherein the first surface of the substrate comprises an outer region that extends a certain distance beyond the perimeter of the optical device region. In one aspect, the article further comprises a transition region between the edge region and the optical device region, the transition region comprising a sidewall of the optical device region. In one aspect, the transition region comprises a radially curved surface between the edge region and the sidewall of the optical device region. In one aspect, the article further comprises an optical stack on the second surface of the substrate. In one aspect, the substrate comprises a first material having a first thermal expansion coefficient, and the optical element comprises a second material having a second thermal expansion coefficient, wherein the first thermal expansion coefficient is different from the second thermal expansion coefficient.

[0071] One aspect of the present disclosure relates to a method of manufacturing a plurality of articles on a substrate, the method comprising: depositing a layer on a first surface of the substrate for forming a plurality of optical device regions, each optical device region corresponding to one of the plurality of articles; and thinning a portion of the layer to form a thinned region between the plurality of optical device regions. In one aspect, the method further comprises cutting the substrate in the thinned region to form individualized articles. In one aspect, each individualized article comprises an outer region of the substrate extending a distance beyond the perimeter of the optical device region. In one aspect, the optical element of each individualized article comprises an edge region on the outer region of the substrate extending partially or completely around the perimeter of the optical device region, the edge region having an edge thickness less than the total thickness of the optical device region. In one aspect, the thinned region has a thickness in the range of about 0 to about 100 microns, such as about 0 to about 50 microns, or any other thickness described herein for the thinned region. In one aspect, the article has reduced material mismatch stress between the optical element and the substrate compared to a second optical device that: i) has a substrate of the same size as the first optical device, and ii) is identical to the first optical device except that the optical element has the same total thickness across the first surface of the substrate.

[0072] One aspect of the present disclosure relates to a source substrate comprising a plurality of articles fabricated by any of the methods described herein.

[0073] One aspect of the present disclosure also relates to a method of performing singulation, the method comprising: thinning a portion of a layer to form a thinned region between a plurality of device regions on a substrate; and cutting the substrate in the thinned region to form singulated devices.

[0074] From the foregoing description, those skilled in the art will recognize that the present teachings can be implemented in various forms. Therefore, although these teachings are described with respect to their specific embodiments and examples, the true scope of the present teachings should not be so limited. Various changes and modifications may be made without departing from the scope of the present teachings.

[0075] This scope disclosure will be interpreted broadly. The disclosure is intended to disclose equivalents, devices, systems and methods for the devices, activities and mechanical actions disclosed herein. For each device, article, method, device, mechanical element or mechanism disclosed, the disclosure is intended to also include and teach in its disclosure the equivalents, devices, systems and methods for practicing the many aspects, mechanisms and devices disclosed herein. The claims of the present application will be interpreted broadly as well. The description of the invention herein is essentially only exemplary in its many embodiments, and therefore the deformation that does not deviate from the gist of the present invention is intended to be within the scope of the present invention. Such deformation should not be regarded as departing from the spirit and scope of the present invention.

Claims

1. A product comprising: a substrate having a first surface and a second surface opposite to the first surface; and an optical element on the first surface of the substrate, the optical element comprising an optics region; The first surface of the substrate includes an outer region, and the outer region extends a certain distance beyond the periphery of the optical device region.

2. The article according to claim 1, wherein The optical element further includes an edge region on the outer region of the substrate, the edge region extending partially or completely around a perimeter of the optic region, the edge region having an edge thickness that is less than a thickness of the optic region.

3. The article according to claim 2, wherein A ratio of the edge thickness to the thickness of the optic region is in a range from about 0 to about 0.

95.

4. The article according to claim 3, wherein The edge region has an edge width, wherein a ratio of the edge width to an overall width of the substrate is in a range from about 0.001 to about 0.

999.

5. The article according to claim 4, wherein The edge thickness is substantially uniform.

6. The article according to claim 2, wherein: The bonding characteristics of the edge region of the optical element to the substrate are enhanced compared to the bonding characteristics of the optic region to the substrate.

7. The article according to claim 2, wherein: An outer surface of the edge region of the optical element has a surface roughness in a range of about 0.025 μm to about 500 μm.

8. The article according to claim 2, wherein: The optic region is a diffuser having a base thickness less than a total thickness of the optic region, and a ratio of the edge thickness to the base thickness is in a range of 0 to about 0.

95.

9. The article of claim 1 further comprising a transition region between the edge region and the optic region, the transition region comprising a sidewall of the optic region.

10. The article according to claim 9, wherein The sidewalls are angled relative to a plane of the edge region.

Images