Nanoimprint master, optical waveguide, and method for manufacturing same

Abstract

The invention provides a nanoimprint master mask, an optical waveguide and a manufacturing method of the nanoimprint master mask and the optical waveguide. The nanoimprint master mask and the optical waveguide can solve the problems that in the nanoimprint process, the edge of a grating structure area is poor, and residual glue is not uniform. The nanoimprint master mask comprises: a grating structure region; the non-grating structure region is positioned on the periphery of the grating structure region; and the sinking structure is arranged at a position, which is adjacent to the grating structure area, on the non-grating structure area, and the sinking structure extends along the peripheral direction of the grating structure area so as to surround the grating structure area.

Description

Technical Field

[0001] The present invention relates to the technical field of nanoimprinting, and in particular to a nanoimprinting master and an optical waveguide and a manufacturing method thereof. Background Art

[0002] Nanoimprint technology is a new type of micro-nano processing technology, which transfers micro-nano image structures to the corresponding substrate through a template. It can overcome the difficulties of traditional photolithography in reducing feature size, and has the advantages of feature size up to nanometer level, high resolution and low cost. Although the AR / VR industry has developed and upgraded, the production process of nanoimprint technology for optical waveguide products has gradually become industrialized, but there are also some process difficulties in preparing optical waveguide products through nanoimprint technology. Among them, the edge of the grating structure area of ​​the nanoimprint product cannot be completely fitted with the substrate due to the large height difference between the grating structure area and the non-grating structure area, resulting in poor edges and uneven residual glue defects in the grating structure area, which seriously affects the optical display performance of the optical waveguide. Summary of the invention

[0003] One advantage of the present invention is that it provides a nanoimprint master and an optical waveguide and a method for manufacturing the same, which can solve the defect problems of poor edge and uneven residual adhesive in the grating structure area in the nanoimprint process.

[0004] Another advantage of the present invention is to provide a nanoimprint master and an optical waveguide and a method for manufacturing the same. In one embodiment of the present invention, the nanoimprint master can reduce the height difference between the top of the grating transferred by the imprinting and the top of the glue layer in the non-structured area through a sinking process, thereby avoiding defects caused by the sub-plate not being able to contact the imprinting substrate due to excessive height difference.

[0005] Another advantage of the present invention is to provide a nanoimprint master and an optical waveguide and a method for manufacturing the same, wherein, in one embodiment of the present invention, the nanoimprint master can reduce or eliminate the problems of poor edges and uneven residual glue in the grating structure area by reducing the height difference.

[0006] Another advantage of the present invention is to provide a nanoimprint master and an optical waveguide and a method for manufacturing the same, wherein, in one embodiment of the present invention, the nanoimprint master can reserve a spacing between the sinker structure and the grating structure region to protect the grating structure from damage.

[0007] Another advantage of the present invention is to provide a nanoimprint master and an optical waveguide and a method for manufacturing the same, wherein, in one embodiment of the present invention, the nanoimprint master can ensure that the grating teeth at the edge of the grating structure area are better restored after imprinting.

[0008] Another advantage of the present invention is to provide a nanoimprint master and optical waveguide and a method for manufacturing the same, wherein in order to achieve the above-mentioned purpose, no expensive materials or complicated structures are required in the present invention. Therefore, the present invention successfully and effectively provides a solution, not only providing a simple nanoimprint master and optical waveguide and a method for manufacturing the same, but also increasing the practicality and reliability of the nanoimprint master and optical waveguide and a method for manufacturing the same.

[0009] In order to achieve at least one of the above advantages or other advantages and purposes of the present invention, the present invention provides a nanoimprint master, comprising:

[0010] Grating structure area;

[0011] a non-grating structure region, wherein the non-grating structure region is located around the grating structure region; and

[0012] The sinker structure is disposed on the non-grating structure region and adjacent to the grating structure region, and the sinker structure extends along the peripheral direction of the grating structure region to surround the grating structure region.

[0013] According to an embodiment of the present application, the distance between the inner edge of the sinker structure and the outer edge of the grating structure region is between 0.01 um and 1000 um.

[0014] According to an embodiment of the present application, the processing width of the sinking structure is greater than or equal to 0.01 um.

[0015] According to one embodiment of the present application, the processing depth of the sinking structure is between 0.01um and 100um.

[0016] According to an embodiment of the present application, the sinker structure includes an annular groove recessed from the surface of the non-grating structure region.

[0017] According to an embodiment of the present application, the groove depth of the annular groove is equal to the theoretical depth of the sinking structure.

[0018] According to one embodiment of the present application, the theoretical depth ΔH of the sinking structure satisfies the relationship: ΔH=H1*(1-L / P); wherein H1 is the grating height of the grating structure region; L is the grating line width of the grating structure region; and P is the grating period of the grating structure region.

[0019] According to an embodiment of the present application, the sinking structure includes a plurality of annular grooves that are recessed from the surface of the non-grating structure region and are interconnected, and the depths of the plurality of annular grooves decrease from inside to outside to form stepped grooves.

[0020] According to one embodiment of the present application, the difference between the groove depths of two adjacent annular grooves is equal to the allowable depth of the sub-plate, and the allowable depth of the sub-plate is determined by the sub-plate material and the thickness of the sub-plate.

[0021] According to one embodiment of the present application, the number N of the annular grooves satisfies the relationship: N=ROUNDUP(ΔH / Δh); wherein ROUNDUP is a rounding up function; ΔH is a theoretical depth of the sinking structure; and Δh is an allowable depth of the sub-plate.

[0022] According to another aspect of the present application, the present application further provides an optical waveguide, comprising:

[0023] a waveguide substrate; and

[0024] A coupling grating is formed on the waveguide substrate by nanoimprinting using any of the nanoimprint masters described above.

[0025] According to another aspect of the present application, the present application further provides a method for manufacturing a nanoimprint master, comprising:

[0026] Step S100: Calculate the theoretical depth ΔH=H1*(1-L / P) of the sinking structure based on the grating height H1, the grating line width L and the grating period P of the grating structure region;

[0027] Step S200: obtaining the sub-plate allowable depth Δh based on the sub-plate material and sub-plate thickness;

[0028] Step S300: comparing the allowable depth Δh of the sub-plate with the theoretical depth ΔH of the sunken structure;

[0029] Step S400: if Δh≥ΔH, then no sinking structure is provided at a position adjacent to the grating structure region on the non-grating structure region; or, a position adjacent to the grating structure region on the non-grating structure region is etched to form a single annular groove, wherein the groove depth of the annular groove is equal to the theoretical depth of the sinking structure; and

[0030] Step S500: If Δh<ΔH, a sinker structure is disposed on the non-grating structure region at a position adjacent to the grating structure region.

[0031] According to an embodiment of the present application, step S500 includes:

[0032] Step S510: rounding down ΔH / Δh to obtain the number N of annular grooves of the sinking structure; and

[0033] Step S520: etching a position on the non-grating structure region adjacent to the grating structure region to form N annular grooves, wherein N is a positive integer.

[0034] According to an embodiment of the present application, step S500 includes:

[0035] Step S510': adjusting the daughter plate material and the daughter plate thickness to improve the daughter plate allowable depth to obtain the daughter plate allowable improved depth Δh';

[0036] Step S520': if Δh'≥ΔH, then no sinking structure is provided at a position adjacent to the grating structure region on the non-grating structure region; or, a position adjacent to the grating structure region on the non-grating structure region is etched to form a single annular groove, wherein the groove depth of the annular groove is equal to the theoretical depth of the sinking structure;

[0037] Step S530': if Δh'<ΔH, round down ΔH / Δh' to obtain the number N of annular grooves of the sinking structure; and

[0038] Step S540 ′: etching a position on the non-grating structure region adjacent to the grating structure region to form N annular grooves, wherein N is a positive integer.

[0039] According to one embodiment of the present application, when N=1, the depth of the annular groove is equal to the theoretical depth of the sinking structure; when N≥2, multiple annular grooves are interconnected, wherein the depths of the multiple annular grooves decrease successively from the inside to the outside, and the difference between the depths of two adjacent annular grooves is equal to the allowable depth of the sub-plate.

[0040] According to another aspect of the present application, the present application further provides a method for manufacturing an optical waveguide, comprising:

[0041] Manufacturing a nanoimprint master by any of the above-mentioned methods for manufacturing a nanoimprint master;

[0042] Imprinting a daughter substrate with the nanoimprint master to form a nanoimprint daughter substrate after curing; and

[0043] The waveguide substrate is imprinted by the nanoimprinting plate to form an optical waveguide after curing. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a schematic structural diagram of a nanoimprint master according to an embodiment of the present application;

[0045] Figure 2 A first example of a nanoimprint master according to the above-described embodiment of the present application is shown;

[0046] Figure 3 Shows Figure 2 A partial enlarged schematic diagram of the nanoimprint master;

[0047] Figure 4A second example of the nanoimprint master according to the above embodiment of the present application is shown;

[0048] Figure 5 is a schematic flow chart of a method for manufacturing a nanoimprint master according to an embodiment of the present application;

[0049] Figure 6 A first example of step S500 in the method for manufacturing a nanoimprint master according to the above embodiment of the present application is shown;

[0050] Figure 7 A second example of step S500 in the method for manufacturing a nanoimprint master according to the above embodiment of the present application is shown;

[0051] Figure 8 is a schematic structural diagram of an optical waveguide according to an embodiment of the present application;

[0052] Fig. 9 is a schematic flow chart of a method for manufacturing an optical waveguide according to an embodiment of the present application;

[0053] Fig.10 One example of the method of manufacturing the optical waveguide according to the above-described embodiment of the present application is shown.

[0054] Explanation of the main component symbols: 10, nanoimprint master; 11, grating structure area; 111, coupling-in grating structure area; 112, coupling-out grating structure area; 12, non-grating structure area; 13, sinking structure; 130, annular groove; 131, coupling-in sinking structure; 132, coupling-out sinking structure; 20, optical waveguide; 21, waveguide base; 211, waveguide substrate; 212, waveguide glue; 22, coupling grating; 221, coupling-in grating; 222, coupling-out grating; 30, nanoimprint daughter plate; 300, daughter plate base; 31, daughter plate substrate; 32, daughter plate glue.

[0055] The above description of the main component symbols is combined with the accompanying drawings and specific implementation methods to further illustrate the present application in detail. DETAILED DESCRIPTION

[0056] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0057] Those skilled in the art should understand that, in the disclosure of the present invention, the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0058] In the present invention, the term "one" in the claims and the specification should be understood as "one or more", that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple. Unless it is clearly indicated in the disclosure of the present invention that the number of the element is only one, the term "one" cannot be understood as unique or single, and the term "one" cannot be understood as a limitation on the quantity.

[0059] In the description of the present invention, it should be understood that "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through a medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0060] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0061] In the process of analyzing the nanoimprinting process, the applicant found that the main reasons for the poor edge and uneven residual glue defects in the grating structure area are: when the sub-plate is imprinting the product, there is a large height difference between the top of the grating in the grating structure area and the top of the glue layer in the non-grating structure area, and the thickness of the product glue layer is relatively thin, resulting in the sub-plate outside the grating structure area cannot be bonded to the substrate, resulting in poor edges, forming a ring-shaped defective band, which seriously affects the product appearance and optical display performance; during the imprinting and bonding process, the sub-plate at the edge of the grating structure area will be concave and deformed, resulting in the edge glue of the grating structure area cannot be fully filled, resulting in uneven residual glue defects, which will further affect the optical display performance.

[0062] In order to solve this problem, the present application creatively proposes a nanoimprint master and an optical waveguide and a method for manufacturing the same, which can solve the problems of poor edges and uneven residual glue in the grating structure area in the nanoimprint process, enhance the optical display performance, and improve the product appearance.

[0063] Specifically, refer to the accompanying drawings of the specification of this application. Figures 1 to 4 According to an embodiment of the present application, a nanoimprint master 10 is provided, which may include a grating structure region 11, a non-grating structure region 12 located around the grating structure region 11, and a sinker structure 13. The sinker structure 13 is disposed on the non-grating structure region 12 at a position adjacent to the grating structure region 11, and the sinker structure 13 extends along the peripheral direction of the grating structure region 11 to surround the grating structure region 11.

[0064] More specifically, if Figure 2 and Figure 4 As shown, the nanoimprint master 10 of the present application may have one or more grating structure regions 11, and in this case, the nanoimprint master 10 also requires a corresponding number of sinking structures 13, and the sinking structures 13 surround the grating structure regions 11 one by one. For example, the nanoimprint master 10 may include an input grating structure region 111 and an output grating structure region 112 arranged at intervals, and the nanoimprint master 10 needs to perform sinking treatment on the peripheries of the input grating structure region 111 and the output grating structure region 112, respectively, to obtain an input sinking structure 131 surrounding the input grating structure region 111 and an output sinking structure 132 surrounding the output grating structure region 112, so as to ensure that the input grating and the output grating formed by imprint transfer do not have the problems of poor edges and uneven residual glue.

[0065] It is noteworthy that, since a sinking structure 13 surrounding the grating structure region 11 is provided on the non-grating structure region 12 in the nanoimprint master 10 adjacent to the grating structure region 11, the difference between the top height of the grating transferred by the nanoimprint master 10 and the top height of the glue layer in the non-grating structure region is reduced, thereby reducing or eliminating the defects of poor edge and uneven residual glue in the grating structure region caused by excessive height difference.

[0066] Alternatively, if Figure 3 As shown, the distance A between the inner edge of the sinking structure 13 and the outer edge of the grating structure area 11 can be between 0.01um and 1000um, so as to protect the grating structure in the grating structure area 11 from damage. It can be understood that the distance A mentioned in the present application can be adjusted according to factors such as the filling property of the sub-plate material and the thickness of the sub-plate, and the present application will not repeat it in detail.

[0067] Alternatively, if Figure 3 As shown, the processing width B of the sinking structure 13 can be greater than or equal to 0.01um to avoid the problem of poor ring shape caused by too small processing width B of the sinking structure 13. It can be understood that the processing width B mentioned in this application is related to the firmness of the sub-plate material, that is, the firmer the sub-plate material, the larger the required processing width B.

[0068] In addition, the processing width B of the sinking structure 13 may be less than or equal to the width of the non-grating structure area 12, that is, the sinking structure 13 may at most cover the entire non-grating structure area 12. Optionally, the processing width B of the sinking structure 13 is usually less than or equal to 30 cm.

[0069] Optionally, the processing depth of the sinking structure 13 may be between 0.01 um and 100 um to ensure that the sub-plate can be in close contact with the imprinting substrate (such as a waveguide substrate).

[0070] It is worth noting that Figure 3 As shown, the processing depth of the sinking structure 13 can be set according to the theoretical depth ΔH of the sinking structure 13, and the theoretical depth ΔH of the sinking structure 13 can be calculated according to the grating height H1, the residual glue thickness H2, and the imprint thickness H3 of the non-grating structure area of ​​the actual product, and the relationship satisfies: ΔH=H1+H2-H3; H1*L+P*H2=H3*P, wherein L is the grating line width of the grating structure area 11; P is the grating period of the grating structure area 11.

[0071] After sorting out, it can be known that the theoretical depth ΔH of the sinking structure 13 satisfies the relationship ΔH=H1*(1-L / P); wherein H1 is the grating height of the grating structure area 11; L is the grating line width of the grating structure area 11; and P is the grating period of the grating structure area 11.

[0072] It is understandable that the sum of the grating height of the grating structure area and the thickness of the residual glue area of ​​the actual product is greater than the thickness of the non-grating structure area. The present application defines their difference as the theoretical depth ΔH of the sinking structure 13, and the theoretical depth ΔH of the sinking structure 13 and the allowable depth Δh of the sub-plate jointly determine whether a ring defect will occur, wherein the allowable depth Δh of the sub-plate is determined by the sub-plate material / material and the thickness of the sub-plate. If the allowable depth Δh of the sub-plate is greater than or equal to the theoretical depth ΔH of the sinking structure 13, the ring defect will not occur even if the sinking structure is not set; and if the allowable depth Δh of the sub-plate is less than the theoretical depth ΔH of the sinking structure 13, the sinking structure needs to be set to prevent the ring defect.

[0073] It is worth noting that in order to further improve the problem of uneven residual adhesive, even if the allowable depth Δh of the daughter plate is greater than or equal to the theoretical depth ΔH of the sinking structure 13 , the nanoimprint master 10 of the present application can still be provided with the sinking structure 13 .

[0074] For example, in the first example of the present application, Figure 2 and Figure 3 As shown, the sinking structure 13 may include a single annular groove 130 sunken from the surface of the non-grating structure area 12 to surround the grating structure area 11, so that there is a buffer between the top height of the grating after printing and the top height of the glue layer in the non-grating structure area, avoiding defects caused by the sub-plate not being able to contact the printing substrate due to excessive height difference, such as uneven residual glue at the edge of the grating structure area.

[0075] Alternatively, if Figure 3 As shown, the depth of the annular groove 130 may be equal to the theoretical depth ΔH of the sinking structure 13. It is understandable that in other examples of the present application, the depth of the annular groove 130 may also be greater than the theoretical depth ΔH, as long as it is not greater than the allowable depth Δh of the sub-plate.

[0076] It is worth noting that when the sub-plate allowable depth Δh is less than the theoretical depth ΔH of the sinking structure 13, if the sinking structure 13 only includes a single annular groove, the groove depth of the annular groove will be greater than the sub-plate allowable depth Δh, and the problem of poor annularity will still exist. Figure 4 As shown, the sinking structure 13 may include a plurality of annular grooves 130 which are recessed from the surface of the non-grating structure area 12 and interconnected, and the depths of the plurality of annular grooves 130 decrease from the inside to the outside to form step grooves, which is helpful in solving the annular defects formed due to excessive groove depth.

[0077] Alternatively, if Figure 4As shown, the difference in groove depth between two adjacent annular grooves 130 may be equal to the allowable depth Δh of the sub-plate, so as to avoid the problem of annular defects caused by the difference in groove depth between two adjacent annular grooves 130 being greater than the allowable depth Δh of the sub-plate.

[0078] Optionally, the number N of the annular grooves 130 may satisfy the relationship: N = ROUNDUP (ΔH / Δh); wherein ROUNDUP is a round-up function; ΔH is the theoretical depth of the sinking structure; and Δh is the allowable depth of the sub-plate. Thus, the number N mentioned in the present application is a positive integer greater than 1, for example, when ΔH / Δh = 1.2, N = 2; when ΔH / Δh = 2.5, N = 3, so as to ensure that the difference in the groove depth of two adjacent annular grooves 130 is not greater than the allowable depth Δh of the sub-plate.

[0079] In summary, the sinking structure 13 mentioned in the present application can be, but is not limited to, implemented as one or more annular grooves 130 formed in the non-grating structure area 12 by etching. It can be understood that the ring mentioned in the present application is not limited to a circular ring, and can also be implemented as a rectangular ring or other types of annular structures, as long as it matches the shape of the grating structure area 11, and the present application will not elaborate on this.

[0080] It is worth mentioning that according to another aspect of the present application, Figure 5 As shown, one embodiment of the present application further provides a method for manufacturing a nanoimprint master, which may include:

[0081] Step S100: Calculate the theoretical depth ΔH=H1*(1-L / P) of the sinking structure based on the grating height H1, the grating line width L and the grating period P of the grating structure region;

[0082] Step S200: obtaining the sub-plate allowable depth Δh based on the sub-plate material and sub-plate thickness;

[0083] Step S300: comparing the allowable depth Δh of the sub-plate with the theoretical depth ΔH of the sunken structure;

[0084] Step S400: if Δh≥ΔH, then no sinking structure is provided at a position adjacent to the grating structure region on the non-grating structure region; or, a position adjacent to the grating structure region on the non-grating structure region is etched to form a single annular groove, wherein the groove depth of the annular groove is equal to the theoretical depth of the sinking structure; and

[0085] Step S500 : If Δh<ΔH, disposing a sinker structure on the non-grating structure region adjacent to the grating structure region.

[0086] It is worth noting that in step S400, when Δh≥ΔH, it is not necessary to provide a sinking structure or to provide a single annular groove, both of which can avoid the problem of annular defects.

[0087] Optionally, in the first example of the present application, as Figure 6 As shown, step S500 may include:

[0088] Step S510: rounding up ΔH / Δh to obtain the number N of annular grooves of the sinking structure, where N is a positive integer greater than 1; and

[0089] Step S520: etching the position of the non-grating structure area adjacent to the grating structure area to form N interconnected annular grooves, wherein the depths of the N annular grooves decrease from the inside to the outside, and the difference in the depths of two adjacent annular grooves is equal to the allowable depth of the sub-plate.

[0090] It is worth noting that since the allowable depth Δh of the sub-plate is determined by the material and thickness of the sub-plate, the present application can improve the allowable depth of the sub-plate by adjusting the material (such as glue type) and / or the thickness of the sub-plate to obtain an allowable improvement depth Δh' of the sub-plate that is increased compared to the allowable depth Δh of the sub-plate; at this time, if the allowable improvement depth Δh' of the sub-plate can be greater than or equal to the theoretical depth ΔH of the sinking structure, there is no need to set a sinking structure or only a single annular groove needs to be set to solve the problem of poor annularity; and if the allowable improvement depth Δh' of the sub-plate is still less than the theoretical depth ΔH of the sinking structure, multiple annular grooves must be set to form a step groove to solve the problem of poor annularity.

[0091] For example, in the second example of the present application, Figure 7 As shown, step S500 may include:

[0092] Step S510': adjusting the daughter plate material and the daughter plate thickness to improve the daughter plate allowable depth to obtain the daughter plate allowable improved depth Δh';

[0093] Step S520': if Δh'≥ΔH, then no sinking structure is provided at a position adjacent to the grating structure region on the non-grating structure region; or, a position adjacent to the grating structure region on the non-grating structure region is etched to form a single annular groove, wherein the groove depth of the annular groove is equal to the theoretical depth of the sinking structure;

[0094] Step S530': if Δh'<ΔH, round up ΔH / Δh' to obtain the number N of annular grooves of the sinking structure, where N is a positive integer greater than 1; and

[0095] Step S540': etching the position of the non-grating structure area adjacent to the grating structure area to form N interconnected annular grooves, wherein the depths of the N annular grooves decrease from the inside to the outside, and the difference in depth between two adjacent annular grooves is equal to the allowable depth of the sub-plate.

[0096] It is worth mentioning that according to another aspect of the present application, Figure 8 As shown, an embodiment of the present application further provides an optical waveguide 20, which may include a waveguide substrate 21 and a coupling grating 22. The coupling grating 22 may be formed on the waveguide substrate 21 by nanoimprinting via the above-mentioned nanoimprint master 10, so as to ensure that the edge grating teeth of the coupling grating 22 have a better restoration effect, reducing or eliminating the problems of poor edges and uneven residual glue.

[0097] Alternatively, if Figure 8 As shown, the coupling grating 22 can be implemented as an input grating 221 and an output grating 222 arranged at intervals on the waveguide substrate 21, and the input grating 221 and the output grating 222 correspond to the input grating structure area 111 and the output grating structure area 112 in the nanoimprint master 10. It can be understood that the coupling grating 22 mentioned in the present application can also be implemented as a pupil expansion grating (not shown in the figure) located in the optical path between the input grating 221 and the output grating 222; accordingly, the nanoimprint master 10 is also provided with a pupil expansion grating structure area corresponding to the pupil expansion grating, which will not be described in detail in the present application.

[0098] It is worth mentioning that according to another aspect of the present application, Fig. 9 As shown, an embodiment of the present application further provides a method for manufacturing an optical waveguide, which may include the steps of:

[0099] The nanoimprint master 10 is manufactured by the above-mentioned nanoimprint master manufacturing method;

[0100] Imprinting the daughter substrate 300 by the nanoimprint master 10 to form the nanoimprint daughter substrate 30 after curing; and

[0101] The waveguide substrate 21 is imprinted by the nano-imprinting sub-plate 30 to form the optical waveguide 20 after curing.

[0102] For example, Fig.10 As shown, the sub-plate base 300 mentioned in the present application can be composed of a sub-plate substrate 31 and a sub-plate glue 32 coated on the surface of the sub-plate substrate 31, and the nanoimprint master 10 is imprinted on the sub-plate glue 32 of the sub-plate base 300, so that the nanoimprint sub-plate 30 can be obtained after the sub-plate glue 32 is cured.

[0103] Similarly, if Fig.10As shown, the waveguide base 21 mentioned in the present application can also be composed of a waveguide substrate 211 and a waveguide glue 212 coated on the surface of the waveguide substrate 211 before curing. The nanoimprint sub-plate 30 is imprinted on the waveguide glue 212 of the waveguide base 21, so that the optical waveguide 20 can be obtained after the waveguide glue 212 is cured.

[0104] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0105] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention.

Claims

1. A nanoimprint master, characterized in that: include: Grating structure area; a non-grating structure region, wherein the non-grating structure region is located around the grating structure region; as well as The sinker structure is disposed on the non-grating structure region and adjacent to the grating structure region, and the sinker structure extends along the peripheral direction of the grating structure region to surround the grating structure region.

2. The nanoimprint master according to claim 1, characterized in that: The distance between the inner edge of the sinking structure and the outer edge of the grating structure region is between 0.01 um and 1000 um.

3. The nanoimprint master according to claim 1, characterized in that: The processing width of the sinking structure is greater than or equal to 0.01um.

4. The nanoimprint master according to claim 1, characterized in that: The processing depth of the sinking structure is between 0.01um and 100um.

5. The nanoimprint master according to any one of claims 1 to 4, characterized in that: The sinker structure includes a single annular groove sunken from the surface of the non-grating structure area.

6. The nanoimprint master according to claim 5, characterized in that: The depth of the annular groove is equal to the theoretical depth of the sinking structure.

7. The nanoimprint master according to claim 6, characterized in that: The theoretical depth ΔH of the sinking structure satisfies the relationship: ΔH=H1*(1-L / P); wherein H1 is the grating height of the grating structure region; L is the grating line width of the grating structure region; and P is the grating period of the grating structure region.

8. The nanoimprint master according to any one of claims 1 to 4, characterized in that: The sinking structure includes a plurality of annular grooves which are sunken from the surface of the non-grating structure area and are interconnected. The depths of the plurality of annular grooves decrease from the inside to the outside to form stepped grooves.

9. The nanoimprint master according to claim 8, characterized in that: The difference between the groove depths of two adjacent annular grooves is equal to the allowable depth of the sub-plate, and the allowable depth of the sub-plate is determined by the sub-plate material and the thickness of the sub-plate.

10. The nanoimprint master according to claim 8, characterized in that: The number N of the annular grooves satisfies the relationship: N=ROUNDUP(ΔH / Δh); wherein ROUNDUP is a round-up function; ΔH is a theoretical depth of the sinking structure; and Δh is an allowable depth of the sub-plate.

11. An optical waveguide, characterized in that include: waveguide substrate; and A coupling grating, wherein the coupling grating is formed on the waveguide substrate by nanoimprinting using the nanoimprint master according to any one of claims 1 to 10.

12. A method for manufacturing a nanoimprint master, characterized in that: include: Step S100: Calculate the theoretical depth ΔH=H1*(1-L / P) of the sinking structure based on the grating height H1, the grating line width L and the grating period P of the grating structure region; Step S200: obtaining a sub-plate allowable depth Δh based on the sub-plate material and sub-plate thickness; Step S300: comparing the allowable depth Δh of the sub-plate with the theoretical depth ΔH of the sunken structure; Step S400: if Δh≥ΔH, then no sinking structure is provided at a position adjacent to the grating structure region on the non-grating structure region; or, a position adjacent to the grating structure region on the non-grating structure region is etched to form a single annular groove, wherein the groove depth of the annular groove is equal to the theoretical depth of the sinking structure; as well as Step S500: If Δh<ΔH, a sinker structure is disposed on the non-grating structure region at a position adjacent to the grating structure region.

13. The method for manufacturing a nanoimprint master according to claim 12, characterized in that: The step S500 includes: Step S510: rounding up ΔH / Δh to obtain the number N of annular grooves of the sinking structure, where N is a positive integer greater than 1; and Step S520: etching the position of the non-grating structure area adjacent to the grating structure area to form N interconnected annular grooves, wherein the depths of the N annular grooves decrease from the inside to the outside, and the difference in the depths of two adjacent annular grooves is equal to the allowable depth of the sub-plate.

14. The method for manufacturing a nanoimprint master according to claim 12, characterized in that: The step S500 includes: Step S510': adjusting the daughter plate material and the daughter plate thickness to improve the daughter plate allowable depth to obtain the daughter plate allowable improved depth Δh'; Step S520': if Δh'≥ΔH, then no sinking structure is provided at a position adjacent to the grating structure region on the non-grating structure region; or, a position adjacent to the grating structure region on the non-grating structure region is etched to form a single annular groove, wherein the groove depth of the annular groove is equal to the theoretical depth of the sinking structure; Step S530': if Δh'<ΔH, round up ΔH / Δh' to obtain the number N of annular grooves of the sinking structure, where N is a positive integer greater than 1; and Step S540': etching the position of the non-grating structure area adjacent to the grating structure area to form N interconnected annular grooves, wherein the depths of the N annular grooves decrease from the inside to the outside, and the difference in depth between two adjacent annular grooves is equal to the allowable depth of the sub-plate.

15. A method for manufacturing an optical waveguide, characterized in that: include: Manufacturing a nanoimprint master by the method for manufacturing a nanoimprint master as claimed in any one of claims 12 to 14; Imprinting a daughter substrate with the nanoimprint master to form a nanoimprint daughter substrate after curing; and The waveguide substrate is imprinted by the nanoimprinting plate to form an optical waveguide after curing.

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