Deposition auxiliary structure, optical structure forming method and diffraction optical waveguide

Abstract

A deposition assisting structure, an optical structure forming method and a diffractive optical waveguide, the method comprising: providing a substrate comprising one or more optical structure regions; providing a deposition auxiliary structure, wherein the deposition auxiliary structure is arranged in a direction perpendicular to the surface of the substrate; providing a target material, and arranging the target material above the substrate; the deposition auxiliary structure is arranged between the target material and the substrate, the second auxiliary plate makes contact with the substrate, the second window corresponds to the optical structure area, and the first window corresponds to the target material; and by adjusting the relative positions of the target, the first window and the second window, forming an optical structure material layer of which the thickness is sequentially increased or decreased on the optical structure area. Therefore, the continuous thickness change of the optical structure can be accurately controlled.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a deposition auxiliary structure, a method for forming an optical structure, and a diffraction optical waveguide. Background Art

[0002] In the current augmented reality (AR) field, diffractive waveguide technology is highly respected by the industry for its wide eye movement range, compact size and excellent mass production capabilities. In order to further improve the uniformity of the field of view, color consistency and efficiency of optical transmission, the industry is constantly promoting the design innovation and manufacturing process optimization of diffractive waveguides. Especially in terms of manufacturing process, how to efficiently produce high-performance diffractive waveguides has become a hot topic in industry research.

[0003] How to optimize optical structures to achieve highly continuous changes is an ongoing challenge, especially for diffraction grating structures. Improving the visual effects of optical products while ensuring the diffraction efficiency of the optical structure is a problem that continues to need to be solved. Summary of the invention

[0004] The technical problem solved by the present invention is to provide a deposition auxiliary structure, a method for forming an optical structure and a diffraction optical waveguide, which solves the technical problem of precise control of continuous thickness change of the optical structure.

[0005] To solve the above technical problems, an embodiment of the present invention provides a deposition auxiliary structure, including: a first auxiliary plate, wherein the first auxiliary plate has a first window passing through the first auxiliary plate; a second auxiliary plate, wherein the second auxiliary plate has a second window passing through the second auxiliary plate, and center lines of the first window and the second window do not overlap; there is a spacing between the first auxiliary plate and the second auxiliary plate, and the first window of the first auxiliary plate and the second window of the second auxiliary plate are used to form a material layer with thickness increasing or decreasing successively in the second window; the thickness of the material layer is related to the spacing.

[0006] Optionally, the material layer is used to form a turning grating and / or an outcoupling grating of a diffraction optical waveguide, and the depth of the turning grating and / or the outcoupling grating gradually increases along the direction of light transmission.

[0007] Optionally, the thickness of the material layers increases or decreases sequentially, and the calculation formula of the thickness T(x, y) is defined as: Where M is the mass of the target material, ρ is the density of the target material, h is the distance from the center of the target to the surface of the substrate, T(x, y) is the thickness of the material layer at the coordinate (x, y), H is the distance between the first auxiliary plate and the substrate, m x1is the critical coordinate value of the first window on the left side of the x-axis, m x2 m is the critical coordinate value of the first window on the right side of the x-axis; y1 is the left critical coordinate value of the first window on the y-axis, m y2 is the right critical coordinate value of the first window on the y-axis; are respectively the horizontal coordinate value and the vertical coordinate value of the target sputtering point relative to the target center; when the deposition auxiliary structure is used to assist deposition, it is arranged on the surface of the substrate.

[0008] Optionally, along the direction from the center line of the first window to the center line of the second window, the thickness of the material layer decreases sequentially.

[0009] Correspondingly, the technical solution of the present invention also provides a method for forming an optical structure, comprising: providing a substrate, the substrate comprising one or more optical structure regions; providing a deposition auxiliary structure, the deposition auxiliary structure being arranged perpendicular to the surface direction of the substrate; providing a target material, arranged above the deposition auxiliary structure; arranging the deposition auxiliary structure between the target material and the substrate, the second auxiliary plate being in contact with the substrate, the second window corresponding to the optical structure region, and the first window corresponding to the target material; and forming an optical structure material layer with a thickness that increases or decreases sequentially on the optical structure region by adjusting the relative positions of the target material, the first window and the second window.

[0010] Optionally, an optical structure material layer whose thickness increases or decreases sequentially is formed on the optical structure area by adjusting the relative positions of the target material, the first window, and the second window, including: adjusting the relative positions of the target material, the center line of the first window, and the center line of the second window, so that the relative positions of the target material relative to the first window and the second window meet preset conditions.

[0011] Optionally, the relative position of the target material relative to the first window and the second window satisfies a preset condition, including:

[0012] in, They respectively represent the critical coordinate values ​​of the left boundary in the target's active range; They represent the critical coordinate values ​​of the right boundary of the target's active range; H is the distance between the first auxiliary plate and the substrate; h is the distance from the center of the target to the surface of the substrate; m x1 is the critical coordinate value on the left side of the x-axis in the first window area, m x2 is the critical coordinate value on the right side of the x-axis in the first window area; m y1 is the critical coordinate value on the left side of the y-axis in the first window area, m y2 is the critical coordinate value on the right side of the y-axis in the first window area; ux1 is the critical coordinate value on the left side of the x-axis in the second window area, u y1 u is the critical coordinate value on the left side of the y-axis in the second window area; x2 is the critical coordinate value on the right side of the x-axis in the second window area, u y2 It is the critical coordinate value on the right side of the y-axis in the second window area.

[0013] Optionally, it also includes: the surface of the substrate is flat; a turning grating and / or an outcoupling grating is formed based on the optical structure material layer on the substrate, and the depth of the turning grating and / or the outcoupling grating gradually increases along the direction of light transmission.

[0014] Optionally, the method further includes: the substrate includes: a substrate and a grating structure located on the substrate, and the optical structure material layer is formed on a surface of the grating structure away from the substrate.

[0015] Correspondingly, the technical solution of the present invention also provides a diffraction optical waveguide, which at least includes a coupling-out grating region and / or a turning grating region, and the grating structure in the coupling-out grating region or the turning grating region is prepared based on the method for forming the optical structure described in any of the aforementioned embodiments.

[0016] Compared with the prior art, the technical solution of the embodiment of the present invention has the following beneficial effects: The deposition auxiliary structure provided in the present invention includes a first auxiliary plate and a second auxiliary plate. A material layer with a thickness that increases or decreases sequentially is constructed in the second window area through the first window of the first auxiliary plate and the second window of the second auxiliary plate. Through this auxiliary structure, a continuous change in the thickness of the material layer can be achieved on the substrate. By carefully designing the deposition auxiliary structure, the thickness of the material layer in different areas can be accurately adjusted, thereby manufacturing an optical structure with a continuous gradient change in thickness. First, the structural design of this material layer enables the optical structure to adjust the diffraction efficiency at different positions, thereby enhancing the display uniformity of the optical structure, improving the display efficiency, and optimizing the display quality. Secondly, the design also helps to improve the appearance of the optical structure. By realizing continuous gradual modulation of thickness through a material layer with a thickness that increases or decreases sequentially, a sharp change in thickness in different areas is avoided. Such a design not only improves the dimensional accuracy of the optical structure, but also enhances its visual aesthetics to prevent visual differences caused by sudden changes in thickness at different positions.

[0017] The optical structure forming method of the present invention arranges a deposition auxiliary structure between the target material and the substrate so that the second window corresponds to the optical structure area and the first window corresponds to the target material. By controlling the relative positions of the target material, the first window and the second window and the sputtering process, a material layer with a continuously changing thickness can be formed on the substrate, such as the thickness increasing or decreasing in sequence, so as to accurately control the formation process of the optical structure and improve the display appearance of the optical structure, especially avoiding sudden stripes between different optical structure areas, so that the thickness of each area presents a continuous gradient, and improves the display effect of the optical structure while improving the display efficiency. In addition, based on this method, a grating structure can be formed in a diffraction optical waveguide to achieve continuous gradient modulation of depth, and different grating structures have different depth materials deposited. On the one hand, the method modulates the diffraction efficiency of the grating structure at different positions, especially in the area far away from the incident light source, improves the diffraction efficiency in the distant area, and makes it present a continuously gradual diffraction efficiency at each position, thereby improving the display uniformity and effect of the diffraction optical waveguide; on the other hand, the grating structure depth of the formed diffraction optical waveguide at different positions continuously changes gradually, which is different from the traditional partition structure, avoiding the visual difference caused by the sudden change of thickness, thereby obtaining a better appearance effect visually. The present invention has unexpected technical effects compared with the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 and Figure 2 is a schematic structural diagram of a deposition auxiliary structure in an embodiment of the present invention; Figures 3 to 10 is a schematic structural diagram of a deposition auxiliary structure for forming an optical structure in one embodiment of the present invention; Figures 11 to 14 is a structural schematic diagram of an optical structure forming process in one embodiment of the present invention; Fig.15 and Fig.16 is a structural schematic diagram of an optical structure forming process in another embodiment of the present invention; Fig.17 and Fig.18 It is a structural schematic diagram of the optical structure forming process in another embodiment of the present invention. DETAILED DESCRIPTION

[0019] As described in the background art, how to optimize the optical structure to ensure the diffraction efficiency of the optical structure while improving the visual effect of the optical product is a problem that continues to be solved.

[0020] In order to solve the above technical problems, an embodiment of the present invention proposes a technology for forming an optical structure including a deposition auxiliary structure. By controlling the deposition auxiliary structure and the deposition process, the thickness variation of the material layer in different areas can be precisely manipulated, thereby creating a continuous gradient optical structure with gradually increasing or decreasing thickness; and in this way, a diffraction optical waveguide structure is formed or a grating structure is deposited to form an optical structure with different gradient thicknesses. On the one hand, this structural design can adjust the diffraction efficiency of the optical structure in different areas, enhance its display consistency at various positions, and thus optimize the display quality. On the other hand, the design also improves the appearance of the optical structure by achieving a continuous gradient of thickness and avoiding sudden changes in thickness, which not only improves the dimensional accuracy of the optical structure, but also enhances its visual presentation effect. In order to make the above-mentioned objects, features and beneficial effects of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0021] Figure 1 and Figure 2 Schematic diagram of the structure of the deposition auxiliary structure in an embodiment of the present invention.

[0022] Please refer to Figure 1 and Figure 2 , Figure 2 for Figure 1 A top view of Figure 1 for Figure 2 A schematic diagram of a structure along the section line BB1 ​​direction, wherein the deposition auxiliary structure comprises: a first auxiliary plate 101, wherein the first auxiliary plate 101 has a first window 104 penetrating the first auxiliary plate 101; a second auxiliary plate 102, wherein the second auxiliary plate 102 has a second window 105 penetrating the second auxiliary plate 102, wherein the center line L1 of the first window 104 does not coincide with the center line L2 of the second window 105; and wherein there is a spacing between the first auxiliary plate 101 and the second auxiliary plate 102, wherein the first auxiliary plate 101 and the second auxiliary plate 102 are used to form material layers with increasing or decreasing thicknesses in the second window 105 (such as Figure 6 As shown), the thickness of the material layer is related to the spacing.

[0023] The thickness of the material layer increases or decreases sequentially, including: the thickness in the second window 105 increases or decreases sequentially.

[0024] In this embodiment, the material layer is used to form a turning grating and / or an outcoupling grating of a diffraction optical waveguide, and the depth of the turning grating and / or the outcoupling grating gradually increases along the direction of light transmission.

[0025] In this embodiment, the deposition auxiliary structure also includes: a connecting portion 103, wherein the connecting portion 103 connects the first auxiliary plate 101 and the second auxiliary plate 102, the first auxiliary plate 101 and the second auxiliary plate 102 are connected through the connecting portion 103 to form an integrated structure, and the second auxiliary plate 102 is bonded to the substrate.

[0026] In other embodiments, the deposition auxiliary structure may not include the connection portion, the first auxiliary plate and the second auxiliary plate are independently formed on the substrate, and the second auxiliary plate is in contact with the substrate.

[0027] The above two embodiments of the deposition auxiliary structure are both within the protection scope of the present invention. As long as they do not deviate from the purpose of the present invention, that is, to achieve a material layer with a continuously gradient thickness, no limitation is imposed on the connection method of the mask structure.

[0028] In this embodiment, the projection range of the first window 104 projected onto the second auxiliary plate 102 partially overlaps with the second window 105 , and the projection range of the first window 104 projected onto the second auxiliary plate 102 has an overlapping area with the second window 105 .

[0029] In this embodiment, the area overlap between the overlapping area of ​​the projection of the first window 104 and the projection of the second window 105 is greater than 50%.

[0030] In this embodiment, the center line L1 of the first window 104 does not coincide with the center line L2 of the second window 105 , so as to accurately control the process of forming the material layer with a continuously gradient thickness in the second window 105 .

[0031] In this embodiment, the first auxiliary plate 101 and the second auxiliary plate 102 are arranged in parallel to form a material layer with a preset thickness variation in the second window 105 .

[0032] The first auxiliary plate 101 and the second auxiliary plate 102 are arranged in parallel, which can reduce the risk of interference between the deposition auxiliary structure and the material source or the machine chamber, and facilitates the adjustment of the thickness variation trend of the material formed in the second window 105 .

[0033] The shape of the first window 104 includes a circle, an ellipse, a rectangle, a trapezoid or a polygon, and the number of sides of the polygon is greater than or equal to 5.

[0034] In this embodiment, the shape of the first window 104 includes a circle.

[0035] The shape of the second window 105 includes a rectangle, a trapezoid or a polygon, and the number of sides of the polygon is greater than or equal to 5.

[0036] In one embodiment, the shape of the first window 104 is the same as the shape of the second window 105. The shape of the first window 104 and the shape of the second window 105 include a rectangle, a trapezoid or a polygon.

[0037] In another embodiment, the shape of the first window 104 is different from the shape of the second window 105 .

[0038] The material of the deposition auxiliary structure includes metal or metal alloy, the metal alloy includes stainless steel, iron-nickel alloy, and the metal includes iron, aluminum or titanium.

[0039] The above-mentioned deposition auxiliary structure includes a first auxiliary plate and a second auxiliary plate. Through the first window of the first auxiliary plate and the second window of the second auxiliary plate, a material layer with a thickness that increases or decreases sequentially is constructed in the second window area. Through this auxiliary structure, a continuous change in the thickness of the material layer can be achieved on the substrate. By carefully designing the deposition auxiliary structure, the thickness of the material layer in different areas can be accurately adjusted, thereby manufacturing an optical structure with a continuous gradient change in thickness. First, the structural design of this material layer enables the optical structure to adjust the diffraction efficiency at different positions, thereby enhancing the display uniformity of the optical structure, improving the display efficiency, and optimizing the display quality. Secondly, the design also helps to improve the appearance of the optical structure. By realizing continuous gradual modulation of thickness through a material layer with a thickness that increases or decreases sequentially, a sharp change in thickness in different areas is avoided. Such a design not only improves the dimensional accuracy of the optical structure, but also enhances its visual beauty to prevent visual differences caused by sudden changes in thickness at different positions.

[0040] Figures 3 to 10 is a schematic structural diagram of a deposition auxiliary structure for forming an optical structure in one embodiment of the present invention; Figures 11 to 14 It is a structural schematic diagram of the optical structure forming process in one embodiment of the present invention.

[0041] Please refer to Figure 3 and Figure 4 , Figure 3 for Figure 4 A top view of Figure 4 for Figure 3 A cross-sectional structural schematic diagram is provided, providing a substrate 200, wherein the substrate 200 includes one or more optical structure areas 201.

[0042] The optical structure region 201 is a region where a material layer is subsequently formed.

[0043] In this embodiment, the surface of the substrate 200 is flat.

[0044] like Figure 3As shown, Figure 3 A single optical structure region 201 is schematically shown, and a continuous region 20 is schematically shown, wherein the continuous region 20 includes two or more optical structure regions 201, Figure 3 The continuous area 20 in the figure shows three different optical structure areas 201. The different optical structure areas 201 shown in the figure are only examples and do not constitute a limitation on the structure and position of the optical structure area 201. If multiple optical structure areas 201 are independently separated, or divided into regions, or have other structural shapes, etc., they all belong to the optical structure areas indicated in the present invention. Figure 3 The various structural regions shown are for simple illustration only.

[0045] The material of the substrate 200 includes an inorganic material or a semiconductor material. The inorganic material includes quartz. The semiconductor material includes silicon, silicon carbide, titanium oxide, lithium niobate, germanium, gallium arsenide, etc.

[0046] Please refer to Figure 5 , providing a deposition auxiliary structure, the deposition auxiliary structure comprising: a first auxiliary plate 101 and a second auxiliary plate 102 arranged in a direction perpendicular to the surface of the substrate 200.

[0047] For the specific configuration of the deposition auxiliary structure, please refer to Figure 1 and Figure 2 The text description in will not be repeated here.

[0048] Please continue to refer to Figure 5 There is a first distance H′ between the first auxiliary plate 101 and the second auxiliary plate 102 , the first window 104 has a first aperture R1 , and the second window 105 has a second aperture R2 .

[0049] The first aperture R1 is the maximum size of the first window 104 , and the second aperture R2 is the maximum size of the second window 105 .

[0050] In this embodiment, the first aperture R1 ranges from 6 mm to 10 mm.

[0051] In this embodiment, the second aperture R2 ranges from 10 mm to 50 mm.

[0052] In this embodiment, the first spacing H' is in the range of 25 mm to 35 mm.

[0053] In this embodiment, the first auxiliary plate 101 has a first thickness d1, and the first thickness d1 ranges from 2 micrometers to 500 micrometers.

[0054] In this embodiment, the second auxiliary plate 102 has a second thickness d2, and the second thickness d2 is in a range of 2 micrometers to 500 micrometers.

[0055] The first window 104 has a first area S1 , and the second window 105 has a second area S2 .

[0056] Please refer to Figure 6 , providing a target material 202, disposed above the substrate 200; ... Figure 1 and Figure 2 The deposition auxiliary structure is arranged perpendicular to the surface direction of the substrate; the deposition auxiliary structure is arranged between the target material 202 and the substrate 200, the second auxiliary plate 102 is adjacent to the substrate 200, the first window 104 corresponds to the target material 202, and the second window 105 corresponds to the optical structure area 201; an optical structure material layer is formed on the optical structure area 201 by adjusting the relative positions of the target material 202, the first window 104 and the second window 105, and the optical structure material layer includes a material layer 203 whose thickness increases or decreases sequentially.

[0057] In this embodiment, the thickness of the material layer 1 203 increases or decreases in sequence, including: the thickness of the material layer 1 203 gradually decreases from the center line L1 of the first window 104 to the center line L2 of the second window 105. Or the thickness of the material layer 1 203 gradually increases from the center line L2 of the second window 105 to the center line L1 of the first window 104.

[0058] The thickness specified in the present invention increases or decreases sequentially, and does not require absolute continuity in a mathematical sense. The thickness change difference between adjacent positions of the material layer can be less than 1%, 3% or 5%, etc. The actual thickness change difference can be determined based on the performance requirements of the actual product.

[0059] In this embodiment, the second auxiliary plate 102 is adjacent to the substrate 200 , which includes: the second auxiliary plate 102 is disposed on the substrate 200 and in contact with the substrate 200 .

[0060] In other embodiments, the second auxiliary plate is adjacent to the substrate, including: there is a gap between the second auxiliary plate and the substrate, and the second auxiliary plate is not in direct contact with the substrate.

[0061] In this embodiment, the surface of the target 202 is arranged opposite to the surface of the substrate 200 , that is, the sputtering surface of the target 202 is opposite to the surface of the substrate 200 .

[0062] Please combine Figure 3 Continue to refer Figure 6 , the second window 105 corresponds to the optical structure area 201 , including: the second window 105 corresponds to a single optical structure area 201 .

[0063] In this embodiment, the second window 105 corresponds to the optical structure area 201 , including: the second window 105 and the optical structure area 201 have the same shape and area.

[0064] The second window 105 corresponds to the optical structure area 201 , and the shape and area of ​​the second window 105 determine the shape and area of ​​the material layer 1 203 formed on the surface of the substrate 200 .

[0065] In this embodiment, the first window 104 corresponds to the target 202 , which includes: the center line of the first window 104 coincides with or does not coincide with the center line of the target 202 .

[0066] Of course, in one embodiment, the center line of the first window 104 coincides with the center line of the target material 202, that is, the target material 202 is located at the center position of the first window 104 and the second window 105, so that the thickness of the subsequently formed material layer 1 203 can present a continuous change trend of gradually decreasing thickness along the direction from the center line L1 of the first window 104 to the center line L2 of the second window 105.

[0067] In another embodiment, the center line of the first window 104 does not coincide with the center line of the target material 202 , so as to control the thickness variation trend of the material layer 1 203 .

[0068] The material of the material layer 1 203 includes an inorganic dielectric material or a metal material. The inorganic dielectric material includes titanium oxide, niobium oxide, silicon carbide, silicon oxide, lithium niobate, silicon nitride, tantalum oxide, hafnium oxide, and aluminum oxide; the metal material includes a combination of one or more of copper, aluminum, tungsten, cobalt, nickel, and tantalum.

[0069] The target material 202 may be made of titanium oxide, niobium oxide, silicon carbide, silicon oxide, lithium niobate, silicon nitride, tantalum oxide, hafnium oxide, aluminum oxide or titanium.

[0070] There is a first distance H' between the first auxiliary plate 101 and the second auxiliary plate 102, the first window 104 has a first area S1, and a material layer 203 with increasing or decreasing thickness is formed on the optical structure area 201 by adjusting the relative positions of the first auxiliary plate 101 and the second auxiliary plate 102.

[0071] A material layer 203 whose thickness increases or decreases sequentially is formed on the optical structure area 201 by adjusting the relative positions of the target material 202, the first auxiliary plate 101 and the second auxiliary plate 102, and also includes: adjusting the thickness and thickness variation of the material layer 203 at each position on the optical structure area 201 by adjusting the size of the first spacing H' and the relative positions of the target material 202, the second window 105 and the first window 104.

[0072] The specific process of adjusting the thickness of the material layer 1 203 at each position on the optical structure region 201 by adjusting the size of the first spacing H' and the relative positions of the target 202, the second window 105 and the first window 104 is shown in FIG. Figure 7 , Figure 8 and Fig. 9 , Figure 7 Schematic diagram of establishing a coordinate system based on material layer 1 203. Figure 8 A schematic diagram of establishing a coordinate system for each structure according to the material layer 1 203, Fig. 9 Schematic diagram of coordinates of the relative positions of the target 202 , the first window 104 , and the second window 105 .

[0073] Please refer to Figure 7 , taking the intersection of the thickest position of the material layer 203 and the substrate 200 as the coordinate origin O, a coordinate system (x, y) is established, wherein the horizontal coordinate x of the coordinate system (x, y) is the distance of the material layer 203 along the surface of the substrate 200 relative to the coordinate origin O, and the vertical coordinate y of the coordinate system (x, y) is the thickness of any point on the surface of the material layer 203 in a direction perpendicular to the surface of the substrate 200.

[0074] Please refer to Figure 8 , T (x, y) is the thickness of the material layer 203 at a certain position, a (x, y) is a point in the target 202, m (x, y) is an arbitrary point in the first window 104, H is the distance between the first auxiliary plate 101 and the substrate 200, and h is the distance between the center of the target 202 and the substrate 200.

[0075] In this embodiment, a height H between the first auxiliary plate 101 and the substrate 200 is H′+d2, where H′ is a first distance between the first auxiliary plate 101 and the second auxiliary plate 102 , and d2 is a second thickness of the second auxiliary plate 102 .

[0076] In this embodiment, the distance h from the center of the target 202 to the surface of the substrate 200 is H+d1+the distance between the target and the first auxiliary plate 101 , where d1 is the first thickness of the first auxiliary plate 101 .

[0077] In other embodiments, the second auxiliary plate is not in direct contact with the substrate, and a height H between the first auxiliary plate and the substrate=H'+d2+a distance between the second auxiliary plate and the substrate.

[0078] Please refer to Fig. 9 , a(x,y) is a point in the target 202, and at both ends of the target 202, the critical coordinates of the point a(x,y) in the target 202 are a(x1,y1) and a(x2,y2); m(x,y) is any point in the first window 104, and the critical coordinates of the point m(x,y) in the first window 104 are m(x1,y1) and m(x2,y2).

[0079] according to Figure 7 , Figure 8 and Fig. 9 The thickness of the material layer 1 203 in the overlapped area of ​​the second window 105 and the first window 104 is obtained.

[0080] Where M is the mass of the target material, ρ is the density of the target material, h is the distance from the center of the target to the surface of the substrate, T(x, y) is the thickness of the material layer at the coordinate (x, y), H is the distance between the first auxiliary plate and the substrate, m x1 is the critical coordinate value of the first window on the left side of the x-axis, m x2 m is the critical coordinate value of the first window on the right side of the x-axis; y1 is the left critical coordinate value of the first window on the y-axis, m y2 is the right critical coordinate value of the first window on the y-axis; are the abscissa and ordinate values ​​of the target sputtering point relative to the target center, respectively; It is the integration factor of the target sputtering point in the horizontal and vertical coordinate directions of the target; when the deposition auxiliary structure is used to assist deposition, it is arranged on the surface of the substrate.

[0081] The thickness T(x, y) and thickness variation trend of the material layer 1 203 in the second window 105 are controlled by adjusting the relative positions of the target 202 , the center line L1 of the first window 104 , and the center line L2 of the second window 105 .

[0082] Specifically, the thickness variation trend of the material layer 1 203 is along the direction from the center line L1 of the first window 104 to the center line L2 of the second window 105 , and the thickness of the material layer 1 203 gradually decreases. Figure 6It is shown that the center line L1 of the first window 104 is located on the left side of the center line L2 of the second window 105 , so the thickness variation trend of the material layer 1 203 is: in the second window 105 , the thickness of the material layer 1 203 gradually decreases from the left side to the right side.

[0083] Of course, in another embodiment, the thickness of the material layer 1 203 gradually increases from the left side to the right side in the second window 105. The thickness T(x, y) of the material layer 1 203 at different positions x is calculated by the above formula to determine the thickness variation of the material layer 1 203 at different positions. The thickness T(x, y) of the material layer 1 203 at different positions is calculated based on different technical requirements or the gradient requirement of the grating depth.

[0084] Please refer to Fig.10 , Fig.10 For Fig. 9 Based on the schematic diagram, a(x,y) is a point in the target 202. At the two ends of the target 202, the critical coordinates of the point a(x,y) in the target 202 are a(x1,y1) and a(x2,y2). m(x,y) is any point in the first window 104. The critical coordinates of the point m(x,y) in the first window 104 are m(x1,y1) and m(x2,y2). The critical coordinates of the point m(x,y) in the second window 105 are u(x1,y1) and u(x2,y2).

[0085] By adjusting the relative positions of the target 202, the center line L1 of the first window 104 and the center line L2 of the second window 105, the relative position of the target 202 relative to the first window 104 and the second window 105 satisfies a preset condition, wherein the preset condition includes:

[0086] in, They respectively represent the critical coordinate values ​​of the left boundary in the target's active range; They represent the critical coordinate values ​​of the right boundary of the target's active range; H is the distance between the first auxiliary plate and the substrate; h is the distance from the center of the target to the surface of the substrate; m x1 is the critical coordinate value on the left side of the x-axis in the first window area, m x2 is the critical coordinate value on the right side of the x-axis in the first window area; m y1 is the critical coordinate value on the left side of the y-axis in the first window area, m y2 is the critical coordinate value on the right side of the y-axis in the first window area; u x1 is the critical coordinate value on the left side of the x-axis in the second window area, u y1 u is the critical coordinate value on the left side of the y-axis in the second window area;x2 is the critical coordinate value on the right side of the x-axis in the second window area, u y2 It is the critical coordinate value on the right side of the y-axis in the second window area.

[0087] In the above formula, the relative positions of the target material 202, the first window 104, and the second window 105 meet the preset conditions, and can ensure that a material layer 203 with a required thickness increasing or decreasing in sequence is formed in the second window 105.

[0088] The thickness of the material layer 1 203 gradually decreases from the center line L1 of the first window 104 to the center line L2 of the second window 105. Specifically, the thickness of the material layer 1 203 in the second window 105 continuously changes from 15 nanometers to 400 nanometers from the center line L1 of the first window 104 to the center line L2 of the second window 105.

[0089] In this embodiment, the preset size range is 3 cm to 4 cm, or 2 cm to 3 cm, 4 cm to 5 cm, or even less than 2 cm or greater than 5 cm, etc., which are all within the scope of protection requested by the present invention. The present invention does not limit the preset size range. The specific size range can be limited according to the requirements of the optical structure during design, or the regional requirements for forming the grating structure. In this regard, what is shown in the figure is only an example, which is feasible.

[0090] Please refer to Fig.11 A filling layer 204 is formed on the substrate 200 and the material layer 1 203, and the top surface of the filling layer 204 is a flat surface.

[0091] In this embodiment, the method for forming the filling layer 204 includes: forming a filling material layer on the substrate 200 and the material layer 1 203 ; planarizing the filling material layer, and forming the filling layer 204 on the substrate 200 and the material layer 1 203 .

[0092] The material of the filling layer 204 includes photoresist.

[0093] Please refer to Fig.12 , a patterned mask layer 205 is formed on the filling layer 204 .

[0094] In this embodiment, the material of the patterned mask layer 205 includes photoresist.

[0095] Please refer to Fig.13 The filling layer 204 and the material layer 1 203 are etched using the patterned mask layer 205 as a mask until the surface of the substrate 200 is exposed, and an optical structure 206 is formed on the substrate 200, wherein the thickness of the optical structures 206 varies continuously.

[0096] The thickness of the plurality of optical structures 206 changes continuously, including: in the arrangement direction of the plurality of optical structures 206 , the thickness of the plurality of optical structures 206 gradually increases or gradually decreases.

[0097] Specifically, in a direction along the surface of the substrate 200 , the thickness of the optical structure 206 changes continuously from 15 nanometers to 400 nanometers.

[0098] In this embodiment, the plurality of optical structures 206 formed by the material layer 1 203 are used to form a turning grating and / or an outcoupling grating, and the depth of the turning grating and / or the outcoupling grating gradually increases along the direction of light transmission.

[0099] In this embodiment, the material of the material layer 1 203 includes an inorganic dielectric material, and the inorganic dielectric material includes titanium oxide, niobium oxide, silicon carbide, silicon oxide, lithium niobate, silicon nitride, tantalum oxide, hafnium oxide, and aluminum oxide.

[0100] In this embodiment, after the optical structure 206 is formed, the filling layer 204 and the patterned mask layer 205 are removed.

[0101] In another embodiment, after removing the filling layer 204 and the patterned mask layer 205, the method further includes: thinning the substrate 200 to form the optical structure. Specifically, the substrate 200 is etched by an etching process to form an optical structure with a continuously gradient thickness on the substrate.

[0102] In other embodiments, the substrate 200 may not be thinned.

[0103] In other embodiments, the filling layer and the material layer are etched at a preset etching depth using the patterned mask layer as a mask to form an optical structure on the substrate, wherein the optical structure has a plurality of grooves, and the depth of the grooves is less than the depth of the material layer.

[0104] Please refer to Fig.14 In another embodiment, after the optical structure 206 is formed, the substrate 200 is further etched using the optical structure 206 as a mask, so that the substrate 200 is formed into a base 1 210 and a gradient structure 208 located on the base 1 210 .

[0105] The thickness variation trend of the gradual structure 208 is the same as the thickness variation trend of the optical structure 206 .

[0106] In this embodiment, the material of the material layer 1 203 includes metal, and the metal material includes a combination of one or more of copper, aluminum, tungsten, cobalt, nickel and tantalum.

[0107] In summary, the formed optical structure 206 has a thickness that gradually increases or decreases in the arrangement direction of the optical structures 206. Therefore, the thickness variation trend of the optical structure 206 can be accurately controlled, and the thickness variation trend of the optical structures 206 is a continuous variation. The thickness variation of the material layer at different positions can be accurately controlled by designing the deposition auxiliary structure, so as to form an optical structure 206 with a continuous and gradual thickness variation. On the one hand, based on this structural design, the diffraction efficiency modulation of the optical structure 206 at different positions can be realized to improve the display uniformity of the optical structure 206 at different positions and improve the display effect; on the other hand, the design of this structure can also improve the display appearance of the optical structure 206. The design of the continuous and gradual thickness variation can prevent the thickness mutation at different positions. Such a design improves the dimensional accuracy and visual effect of the optical structure.

[0108] The above-mentioned method for forming an optical structure, by setting a deposition auxiliary structure between the target material and the substrate, makes the second window correspond to the optical structure area, and the first window corresponds to the target material. By controlling the relative positions of the target material, the first window and the second window and the sputtering process, a material layer with continuously changing thickness can be formed on the substrate, such as the thickness increasing or decreasing in sequence, so as to accurately control the formation process of the optical structure and improve the display appearance of the optical structure, especially avoiding the sudden stripes between different optical structure areas, so that the thickness of each area presents a continuous gradient, and improves the display effect of the optical structure while improving the display efficiency. In addition, based on this method, a grating structure can be formed in a diffraction optical waveguide to achieve continuous gradient modulation of depth, and different grating structures have different depth materials deposited. On the one hand, the method modulates the diffraction efficiency of the grating structure at different positions, especially in the area far away from the incident light source, improves the diffraction efficiency in the distant area, and makes it present a continuously gradual diffraction efficiency at each position, thereby improving the display uniformity and effect of the diffraction optical waveguide; on the other hand, the grating structure depth of the formed diffraction optical waveguide at different positions continuously changes gradually, which is different from the traditional partition structure, avoiding the visual difference caused by the sudden change of thickness, thereby obtaining a better appearance effect visually. The present invention has unexpected technical effects compared with the prior art.

[0109] Fig.15 and Fig.16 It is a structural schematic diagram of the optical structure forming process in another embodiment of the present invention.

[0110] Please refer to Fig.15 , providing a substrate, wherein the substrate includes a second substrate 300 and a grating structure 1 301 located on the second substrate 300.

[0111] In this embodiment, a plurality of the grating structures 1 301 are separated on the substrate 2 300 , and the heights of the plurality of the grating structures 1 301 are the same.

[0112] Please refer to Fig.16 , using Figures 5 to 10 The method described forms a second material layer 302 on a substrate, wherein the second material layer 302 is located on the side wall surface and the top surface of the grating structure 1 301, and along the arrangement direction of the plurality of the grating structures 1 301, the thickness of the second material layer 302 located on the side wall surface and the top surface of the grating structure 1 301 gradually increases.

[0113] Fig.17 and Fig.18 It is a structural schematic diagram of the optical structure forming process in another embodiment of the present invention.

[0114] Please refer to Fig.17 , providing a substrate, wherein the substrate includes a substrate three 400 and a grating structure two 401 located in the substrate three 400.

[0115] In this embodiment, a plurality of the second grating structures 401 are separated in the third substrate 400 , and the tops of a plurality of the second grating structures 401 are flush with the top of the third substrate 400 .

[0116] Please refer to Fig.18 , using Figures 5 to 10 The method described forms a material layer three 402 on a substrate, and the material layer three 402 is located on the side wall surface and the top surface of the grating structure two 401. Along the arrangement direction of the plurality of grating structures two 401, the thickness of the material layer three 402 located on the side wall surface and the top surface of the grating structure two 401 gradually increases.

[0117] In some other embodiments, the present invention further provides a diffractive optical waveguide, the diffractive optical waveguide at least comprising an outcoupling grating region and / or a turning grating region, the grating structure in the outcoupling grating region or the turning grating region is based on any of the above embodiments ( Figures 3 to 14 Embodiments of Fig.15 and Fig.16 Embodiments of Fig.17 and Fig.18 It is prepared by the method for forming an optical structure described in the embodiment of the present invention.

[0118] Based on the technical effects listed in the aforementioned embodiments, the diffraction optical waveguide obtained by the present invention also has corresponding technical effects. Based on this method, a grating structure can be formed in the diffraction optical waveguide to achieve continuous gradient modulation of depth, and different grating structures have different depth materials deposited. On the one hand, this method modulates the diffraction efficiency of the grating structure at different positions, especially in the area far away from the incident light source, improves the diffraction efficiency of the distant area, and makes it present a continuously gradient diffraction efficiency at each position, thereby improving the display uniformity and effect of the diffraction optical waveguide; on the other hand, the grating structure depth of the formed diffraction optical waveguide at different positions is continuously gradient, which is different from the traditional partition structure, avoiding the visual difference caused by the sudden change of thickness, thereby visually obtaining a better appearance effect. The present invention has unexpected technical effects compared with the prior art.

[0119] It should be noted that, the “grating structure one, grating structure two” in the above embodiments are distinctions made in different embodiments when describing the same feature “grating structure”, the “substrate one, substrate two, substrate three” are distinctions made in different embodiments when describing the same feature “substrate”, and the “material layer one, material layer two, material layer three” are distinctions made in different embodiments when describing the same feature “material layer”.

[0120] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A deposition auxiliary structure, characterized in that: include: a first auxiliary plate, wherein the first auxiliary plate has a first window penetrating the first auxiliary plate; a second auxiliary plate, wherein the second auxiliary plate has a second window penetrating the second auxiliary plate, and center lines of the first window and the second window do not overlap; There is a distance between the first auxiliary plate and the second auxiliary plate, and the first window of the first auxiliary plate and the second window of the second auxiliary plate are used to form a material layer with thickness increasing or decreasing successively in the second window; the thickness of the material layer is related to the distance.

2. The deposition assist structure according to claim 1, wherein: The material layer is used to form a turning grating and / or an outcoupling grating of a diffraction optical waveguide, and the depth of the turning grating and / or the outcoupling grating gradually increases along the direction of light transmission.

3. The deposition assisting structure according to claim 1 or 2, characterized in that: The thickness of the material layers increases or decreases sequentially, and the calculation formula of the thickness T(x, y) is defined as: Where M is the mass of the target material, ρ is the density of the target material, h is the distance from the center of the target to the surface of the substrate, T(x, y) is the thickness of the material layer at the coordinate (x, y), H is the distance between the first auxiliary plate and the substrate, m x1 is the critical coordinate value of the first window on the left side of the x-axis, m x2 is the critical coordinate value of the first window on the right side of the x-axis; m y1 is the left critical coordinate value of the first window on the y-axis, m y2 is the right critical coordinate value of the first window on the y-axis; are respectively the abscissa value and ordinate value of the target sputtering point relative to the target center; when the deposition auxiliary structure is used to assist deposition, it is arranged on the surface of the substrate.

4. The deposition assist structure according to claim 1, wherein: Along the direction from the center line of the first window to the center line of the second window, the thickness of the material layer decreases sequentially.

5. A method for forming an optical structure, characterized in that: include: Providing a substrate, the substrate comprising one or more optical structure regions; Providing a deposition auxiliary structure according to any one of claims 1 to 4, wherein the deposition auxiliary structure is arranged perpendicular to a surface direction of a substrate; Providing a target material, disposed above the deposition auxiliary structure; The deposition auxiliary structure is arranged between the target material and the substrate, the second auxiliary plate is in contact with the substrate, the second window corresponds to the optical structure area, and the first window corresponds to the target material; An optical structure material layer with thickness increasing or decreasing sequentially is formed on the optical structure region by adjusting the relative positions of the target material, the first window and the second window.

6. The method for forming an optical structure according to claim 5, wherein: An optical structure material layer with a thickness that increases or decreases sequentially is formed on the optical structure area by adjusting the relative positions of the target material, the first window, and the second window, including: adjusting the relative positions of the target material, the center line of the first window, and the center line of the second window, so that the relative positions of the target material relative to the first window and the second window meet preset conditions.

7. The method for forming an optical structure according to claim 6, wherein: The relative position of the target material relative to the first window and the second window meets a preset condition, including: in, They respectively represent the critical coordinate values ​​of the left boundary in the target's active range; They represent the critical coordinate values ​​of the right boundary of the target's active range; H is the distance between the first auxiliary plate and the substrate; h is the distance from the center of the target to the surface of the substrate; m x1 is the critical coordinate value on the left side of the x-axis in the first window area, m x2 is the critical coordinate value on the right side of the x-axis in the first window area; m y1 is the critical coordinate value on the left side of the y-axis in the first window area, m y2 is the critical coordinate value on the right side of the y-axis in the first window area; u x1 is the critical coordinate value on the left side of the x-axis in the second window area, u y1 u is the critical coordinate value on the left side of the y-axis in the second window area; x2 is the critical coordinate value on the right side of the x-axis in the second window area, u y2 It is the critical coordinate value on the right side of the y-axis in the second window area.

8. The method for forming an optical structure according to claim 5, wherein: Also includes: The substrate surface is flat; A turning grating and / or an outcoupling grating is formed based on the optical structure material layer on the substrate, and the depth of the turning grating and / or the outcoupling grating gradually increases along the direction of light transmission.

9. The method for forming an optical structure according to claim 5, wherein: Also includes: The substrate comprises: a substrate and a grating structure located on the substrate, and the optical structure material layer is formed on a surface of the grating structure away from the substrate.

10. A diffractive optical waveguide, characterized in that: At least includes a coupling-out grating region and / or a turning grating region, and the grating structure in the coupling-out grating region or the turning grating region is prepared based on the method for forming an optical structure according to any one of claims 5 to 9.

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