Grating manufacturing method and optical waveguide product
Through the one-time etching molding method, the registration accuracy problem caused by multiple partition exposure development is solved, the grating etching efficiency and production quality are improved, and the smooth transition of grating surface height changes is achieved.
Patent Information
- Application Number
- CN202510906006.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-01
- Publication Date
- 2025-08-19
AI Technical Summary
In the prior art, grating etching with multiple surface heights depends on multiple partition exposure development, which easily occurs in registration accuracy problems, and low preparation efficiency. The light effect suddenly changes at the boundary of surface height change, limiting the optical characteristics of optical waveguide products.
By using the one-time etching molding method, by depositing the material to be etched on the grating substrate, etching based on the preset grating height, depositing the hard mask layer and spin-coating the imprinted mask layer, etching the hard mask layer after the grating structure pattern is imprinted, removing the imprinted mask layer and etching the etched film layer based on the target hard mask, and finally removing the hard mask to obtain the target grating.
Efficient etching of multiple surface height gratings is achieved, which avoids registration accuracy issues, reduces sudden changes in the luminous effect at the height of the grating surface height, and improves grating etching efficiency and production quality.
Smart Images
Figure CN120507826A_ABST
Abstract
Description
Technical Field
[0001] The present invention generally relates to the field of optical element manufacturing technology. More specifically, the present invention relates to a grating manufacturing method and an optical waveguide product. Background Art
[0002] A grating is an optical element with a periodic structure. It uses the principles of light interference and diffraction to decompose light into beams of different wavelengths and directions, achieving reflection, filtering, or coupling of specific light. It is widely used in fiber optic communications, optical sensing, and integrated optics. In the field of diffraction optical waveguides, gratings with multiple surface heights can achieve multiple refractions and diffractions of light, thereby improving the brightness uniformity of the optical waveguide and achieving a variety of optical effects. However, the etching of gratings with multiple surface heights relies on multiple partitioned exposure and development, which is prone to overlay errors and has low preparation efficiency. In addition, the optical efficiency of the resulting optical waveguide product is abrupt at the boundary where the surface height changes, resulting in limitations in the optical properties of the product.
[0003] In view of this, there is an urgent need to provide a grating manufacturing method so that a grating with multiple surface heights can be etched and formed in one go, thereby avoiding the registration accuracy problems caused by multiple partition exposure and development, reducing the degree of sudden changes in light effect at the boundaries where the grating surface height changes, improving the grating etching efficiency and improving the grating production quality. Summary of the Invention
[0004] To address at least one or more of the above-mentioned technical issues, the present application proposes a grating fabrication method in various aspects. This grating fabrication method enables single-step etching of gratings with multiple surface heights, avoids registration accuracy issues associated with multiple partitioned exposure and development processes, reduces the degree of sudden changes in light effect at the boundaries of varying grating surface heights, and improves both grating etching efficiency and grating production quality.
[0005] In a first aspect, the present application provides a grating fabrication method, comprising: depositing a material to be etched on a grating substrate; etching the material to be etched based on a preset grating height at each position on the material to be etched to obtain a film layer to be etched; depositing a hard mask layer on the film layer to be etched, and spin-coating an imprinted adhesive mask layer on the hard mask layer; imprinting a grating structure pattern on the imprinted adhesive mask layer, and etching the hard mask layer exposed after imprinting to obtain a target hard mask; removing the imprinted adhesive mask layer, and etching the film layer to be etched based on the target hard mask; and removing the target hard mask to obtain a target grating.
[0006] In some embodiments, etching the material to be etched based on the preset grating height at each position on the material to be etched includes: etching the material to be etched based on the preset grating height at each position on the material to be etched using a gas cluster ion beam etching machine or a reactive ion beam etching machine.
[0007] In some embodiments, etching the exposed hard mask layer after imprinting includes: etching the exposed hard mask layer after imprinting by chemical reaction gas; wherein the chemical reaction gas is any one of fluorine-based gas, chlorine-based gas and a mixture of fluorine-based gas and chlorine-based gas.
[0008] In some embodiments, removing the embossing adhesive mask layer includes removing the embossing adhesive mask layer by dry resist or wet resist stripping.
[0009] In some embodiments, etching the film layer to be etched based on the target hard mask includes: etching the film layer to be etched by an inductively coupled plasma etching machine using the target hard mask as a shield.
[0010] In some embodiments, etching the film to be etched using an inductively coupled plasma etching machine includes: in the inductively coupled plasma etching machine, etching each target etching position of the film to be etched using a preset mixed gas until each target etching position reaches a corresponding target etching depth.
[0011] In some embodiments, the preset mixed gas is a mixed gas of chlorine and octafluorocyclobutane, and the gas ratio of chlorine to octafluorocyclobutane is between 2:1 and 8:1; the power range of the inductively coupled plasma etching machine is between 2500w / 200MHz and 1500w / 400MHz; and the chamber pressure range of the inductively coupled plasma etching machine is between 10mTorr and 20mTorr.
[0012] In some embodiments, removing the target hard mask includes removing the target hard mask using a wet etching solution.
[0013] In some embodiments, depositing the material to be etched on the grating substrate includes depositing any one of TiO2, Si, SiO2, SiN and Nb2O5 on the grating substrate.
[0014] In some embodiments, depositing a hard mask layer on the film to be etched includes depositing any one of Cr, TiN, Al, and Cu on the film to be etched.
[0015] A second aspect of the present application provides an optical waveguide product, comprising a grating manufactured using the grating manufacturing method described in any one of the first aspects.
[0016] The technical solution provided by this application may have the following beneficial effects:
[0017] The grating fabrication method provided in the present application deposits a material to be etched on a grating substrate, and then etches the material to be etched based on a preset grating height at each position on the material to be etched, thereby obtaining a film layer to be etched to meet the required grating size. Furthermore, a hard mask layer is deposited on the film layer to be etched, and an imprinted adhesive mask layer is spin-coated on the hard mask layer. A grating structure pattern is imprinted on the imprinted adhesive mask layer, and the exposed hard mask layer after imprinting is etched to obtain a target hard mask, thereby determining the target position to be etched in the film layer to be etched. Furthermore, the imprinted adhesive mask layer is removed, and the film layer to be etched is etched based on the target hard mask. After the target hard mask is removed, the target grating is obtained. This achieves a single etching process for gratings with multiple surface heights, avoiding the situation where the grating surface height changes greatly due to multiple zone exposure and development, thereby increasing the degree of abrupt change in the light effect at the boundary of the grating surface height change.
[0018] In general, the present application can realize one-time etching of gratings with multiple surface heights, avoid the registration accuracy problems caused by multiple partition exposure and development, reduce the degree of sudden change in light effect at the boundary where the grating surface height changes, improve the grating etching efficiency and improve the grating production quality. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The above and other objects, features and advantages of the exemplary embodiments of the present application will become readily understood by reading the detailed description below with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present application are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:
[0020] Figure 1 FIG1 shows one of the flow charts of the grating manufacturing method according to an embodiment of the present application;
[0021] Figure 2 FIG2 shows a second flow chart of the grating manufacturing method according to an embodiment of the present application;
[0022] Figure 3 A schematic diagram showing a structure of depositing a material to be etched on a grating substrate in a first embodiment of a grating manufacturing method according to an embodiment of the present application is shown;
[0023] Figure 4 A schematic structural diagram of a first embodiment of the grating manufacturing method according to an embodiment of the present application is shown after a material to be etched is etched to obtain a film layer to be etched;
[0024] Figure 5A schematic structural diagram illustrating a first embodiment of a grating fabrication method according to an embodiment of the present application, after a hard mask layer is deposited on a film layer to be etched and an imprinting resin mask layer is spin-coated on the hard mask layer;
[0025] Figure 6 A schematic structural diagram is shown in the first embodiment of the grating manufacturing method according to the embodiment of the present application, after the grating structure pattern is embossed on the embossing mask layer;
[0026] Figure 7 A schematic diagram of the structure after etching the exposed hard mask layer after imprinting, removing the imprinted resist mask layer, and etching the film layer to be etched based on the obtained target hard mask in the first embodiment of the grating manufacturing method of the present application is shown;
[0027] Figure 8 FIG1 shows a schematic structural diagram of a target grating obtained after removing a target hard mask in a first embodiment of a grating manufacturing method according to an embodiment of the present application;
[0028] Figure 9 A schematic structural diagram of depositing a material to be etched on a grating substrate in a second embodiment of the grating manufacturing method according to an embodiment of the present application is shown;
[0029] Figure 10 A schematic structural diagram of a second embodiment of the grating manufacturing method according to an embodiment of the present application is shown after a material to be etched is etched to obtain a film layer to be etched;
[0030] Figure 11 A schematic structural diagram illustrating a second embodiment of the grating fabrication method according to an embodiment of the present application, after a hard mask layer is deposited on a film layer to be etched and an imprinting resin mask layer is spin-coated on the hard mask layer;
[0031] Figure 12 A schematic structural diagram showing a second embodiment of the grating manufacturing method according to an embodiment of the present application after the grating structure pattern is embossed on the embossing mask layer;
[0032] Figure 13 A schematic diagram of the structure after etching the exposed hard mask layer after imprinting, removing the imprinted resist mask layer, and etching the film layer to be etched based on the obtained target hard mask in a second embodiment of the grating manufacturing method of the embodiment of the present application is shown;
[0033] Figure 14 A schematic structural diagram of a target grating obtained after removing the target hard mask in a second embodiment of the grating manufacturing method of the embodiment of the present application is shown.
[0034] In the figure, 1 is a silicon wafer substrate or a glass substrate, 2 is a material to be etched, 3 is a hard mask layer, and 4 is an imprinted adhesive mask layer. DETAILED DESCRIPTION
[0035] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. For the sake of simplicity and clarity of explanation, figure marks may be repeated in the drawings to indicate corresponding or similar elements where appropriate. In addition, this application sets forth many specific details in order to provide a thorough understanding of the embodiments described herein. However, those skilled in the art will understand that the embodiments described herein can be practiced without these specific details. In other cases, well-known methods, processes, and components are not described in detail to avoid obscuring the embodiments described herein. Moreover, this description should not be regarded as limiting the scope of the embodiments described herein. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of this application.
[0036] It should be understood that the terms "first" or "second" and the like in the claims, description, and drawings disclosed in this application are used to distinguish different objects rather than to describe a specific order. The terms "include" and "comprising" used in the description and claims of this application indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.
[0037] It should also be understood that the terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit this application. As used in this specification and claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It should also be further understood that the term "and / or" as used in this specification and claims refers to any and all possible combinations of one or more of the associated listed items, including and including these combinations.
[0038] As used in this specification and claims, the term "if" can be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]," depending on the context.
[0039] A grating is an optical element with a periodic structure. It uses the principles of light interference and diffraction to decompose light into beams of different wavelengths and directions, achieving reflection, filtering, or coupling of specific light. It is widely used in fiber optic communications, optical sensing, and integrated optics. In the field of diffraction optical waveguides, gratings with multiple surface heights can achieve multiple refractions and diffractions of light, thereby improving the brightness uniformity of the optical waveguide and achieving a variety of optical effects. However, the etching of gratings with multiple surface heights relies on multiple partitioned exposure and development, which is prone to overlay errors and has low preparation efficiency. In addition, the optical efficiency of the resulting optical waveguide product is abrupt at the boundary where the surface height changes, resulting in limitations in the optical properties of the product.
[0040] In view of this, an embodiment of the present application provides a grating fabrication method so as to achieve one-time etching of a grating having multiple surface heights, avoid the registration accuracy problems caused by multiple partition exposure and development, reduce the degree of sudden change in light effect at the boundary where the grating surface height changes, improve the grating etching efficiency and improve the grating production quality.
[0041] The specific implementation of the present application will be described in detail below with reference to the accompanying drawings.
[0042] Figure 1 FIG1 shows one of the flow charts of the grating manufacturing method according to an embodiment of the present application. Figure 1 The grating manufacturing method shown in the embodiment of the present application may include:
[0043] In step S101, a material to be etched is deposited on a grating substrate. In the embodiment of the present application, the grating substrate can be a silicon wafer substrate or a glass substrate, and the material to be etched can be a metal oxide with a high refractive index and excellent optical properties, such as but not limited to TiO2, Si, SiO2, SiN, Nb2O5, etc.
[0044] In step S102, the material to be etched is etched based on the preset grating height at each location on the material to be etched, thereby obtaining a film layer to be etched. To achieve multiple refractions and diffractions of light, the grating has multiple surface heights. Therefore, the grating height required to be retained at each location on the material to be etched may be inconsistent. Therefore, it is necessary to perform etching based on the preset grating height at each location on the material to be etched so that the film thickness at each location on the material to be etched (i.e., the retained thickness of the material to be etched) reaches the desired grating surface height. In other words, the preset grating height at each location corresponds to and is the same as the height of the target grating to be ultimately formed, thereby obtaining a film layer to be etched.
[0045] In step S103, a hard mask layer is deposited on the film to be etched, and an imprint adhesive mask layer is spin-coated on the hard mask layer. In the embodiment of the present application, the hard mask layer can be made of materials including but not limited to Cr, TiN, Al, Cu, etc. Imprint adhesive is a material used in nanoimprint lithography (NIL), which is mainly used to replicate nanostructures on a template onto a substrate.
[0046] In step S104, a grating structure pattern is imprinted on the imprinted adhesive mask layer, and the hard mask layer exposed after imprinting is etched to obtain a target hard mask. The aforementioned grating structure pattern can be, for example, a sequence of parallel grooves of a grating. After imprinting the grating structure pattern on the imprinted adhesive mask layer, the desired etching location on the film layer to be etched can be determined. The hard mask layer then acts as a limiter. After imprinting is completed, the local portion of the hard mask layer corresponding to the desired etching location on the film layer to be etched will be exposed. The exposed hard mask layer (i.e., the aforementioned local portion of the hard mask layer) needs to be etched to open it before further etching of the film layer to be etched beneath the hard mask layer.
[0047] In step S105, the imprinted mask layer is removed, and the film to be etched is etched based on the target hard mask. In the embodiment of the present application, the target hard mask can be used as a shield, and then the exposed film to be etched corresponding to the etching opening position of the hard mask layer is etched.
[0048] In step S106, the target hard mask is removed to obtain the target grating. After the target hard mask is removed, the grating structure pattern is retained on the film layer to be etched, thereby obtaining the desired target grating.
[0049] The grating fabrication method of the embodiment of the present application deposits the material to be etched on a grating substrate, and then etches the material to be etched based on the preset grating height at each position on the material to be etched to obtain a film layer to be etched to meet the required grating size. Furthermore, a hard mask layer is deposited on the film layer to be etched, and an imprinted adhesive mask layer is spin-coated on the hard mask layer. The grating structure pattern is imprinted on the imprinted adhesive mask layer, and the hard mask layer exposed after imprinting is etched to obtain a target hard mask, thereby determining the target position to be etched in the film layer to be etched. Furthermore, the imprinted adhesive mask layer is removed, and the film layer to be etched is etched based on the target hard mask. After the target hard mask is removed, the target grating is obtained. This achieves a single etching process for gratings with multiple surface heights, avoiding the situation where the grating surface height changes greatly due to multiple partitioned exposure and development, which results in an increase in the degree of abrupt change in the light effect at the boundary of the grating surface height change.
[0050] In general, the present application can realize one-time etching of gratings with multiple surface heights, avoid the registration accuracy problems caused by multiple partition exposure and development, reduce the degree of sudden change in light effect at the boundary where the grating surface height changes, improve the grating etching efficiency and improve the grating production quality.
[0051] In some embodiments, the process flow for obtaining the target grating can be further designed. Figure 2 The second flow chart of the grating manufacturing method according to the embodiment of the present application is shown. Figure 2 The grating manufacturing method shown in the embodiment of the present application may include:
[0052] In step S201, a material to be etched is deposited on a grating substrate. In the embodiment of the present application, any one of TiO2, Si, SiO2, SiN, and Nb2O5 can be deposited on the grating substrate. It is understood that a variety of materials can be deposited on the grating substrate. In practical applications, the appropriate material to be etched must be selected based on the actual application, and this application does not impose any limitations in this regard.
[0053] In step S202, the material to be etched is etched by a gas cluster ion beam etching machine or a reactive ion beam etching machine according to the preset grating height at each position on the material to be etched. Gas cluster ion beam (GCIB) etching technology is an advanced surface treatment and etching technology that utilizes the interaction between the gas cluster ion beam and the surface of the target material to stimulate a variety of physical and chemical reactions to achieve precise pattern etching. Reactive ion beam etching (RIBE) is an etching technology that combines physical bombardment and chemical reaction, and is mainly used for high-precision material processing and pattern transfer. Etching is performed according to the preset grating height at each position on the material to be etched, so that the film thickness at each position on the material to be etched (i.e., the retained thickness of the material to be etched) reaches the required grating surface height, thereby obtaining the film layer to be etched.
[0054] In step S203, a hard mask layer is deposited on the film layer to be etched, and a stamping adhesive mask layer is spin-coated on the hard mask layer. In the embodiment of the present application, any one of Cr, TiN, Al, and Cu can be deposited on the film layer to be etched. It is understood that the hard mask layer materials that can be used to deposit on the film layer to be etched are diverse. In actual applications, it is necessary to select a suitable hard mask layer material based on the actual application situation. The present application does not impose any restrictions in this regard. In addition, the stamping adhesive in the stamping adhesive mask layer can also be a photoresist, which also needs to be determined based on the actual application situation. The present application does not impose any restrictions in this regard.
[0055] In step S204, a grating structure pattern is imprinted on the imprinted adhesive mask layer, and the exposed hard mask layer is etched using a chemical reaction gas to obtain a target hard mask. In the embodiment of the present application, the chemical reaction gas can be any one of a fluorine-based gas, a chlorine-based gas, and a mixture of a fluorine-based gas and a chlorine-based gas.
[0056] In step S205, the imprint adhesive mask layer is removed by dry ash glue or wet stripping, and the film layer to be etched is etched based on the target hard mask. Dry ash glue (Dry Ashing) is a process that utilizes plasma technology to remove imprint adhesive, photoresist and its residues. Through the action of high-energy oxygen plasma, the imprint adhesive and photoresist are oxidized and decomposed into gaseous products (such as CO2, H2O, etc.), which are then extracted by the vacuum system, thereby achieving the removal of the imprint adhesive and photoresist. Wet stripping (Wet Strip) is a process that removes imprint adhesive, photoresist and its residues by chemical solution, and is widely used in the fields of semiconductor manufacturing, micro-electromechanical systems (MEMS) and optical devices. It is understandable that the methods for removing the imprint adhesive mask layer are various. In actual applications, it is necessary to select a suitable imprint adhesive mask layer removal method according to the actual application situation. The present application does not impose any restrictions in this regard.
[0057] In an embodiment of the present application, the target hard mask can be used as a shield to etch the film layer to be etched using an inductively coupled plasma (ICP) etcher. Conventionally, a reactive ion beam etcher (RIBE) can etch teeth of varying heights by controlling the etch time using a shutter, but the shutter rotation angle and rate are difficult to control, resulting in low efficiency and a long etching time. Furthermore, materials such as TiO2, Si, SiO2, SiN, and Nb2O5 have high chemical bond energies and are difficult to etch. Therefore, the present application employs an inductively coupled plasma (ICP) etcher to etch the film layer to reduce etching time and difficulty, thereby improving the efficiency and quality of grating preparation.
[0058] Specifically, in an inductively coupled plasma etching machine, each target etching location of the film layer to be etched can be etched using a preset mixed gas until each target etching location reaches a corresponding target etching depth. The preset mixed gas is a mixture of chlorine and octafluorocyclobutane, with a gas volume ratio of chlorine to octafluorocyclobutane between 2:1 and 8:1. The power range of the inductively coupled plasma etching machine is 2500W / 200MHz to 1500W / 400MHz, and the chamber pressure range of the inductively coupled plasma etching machine is between 10mTorr and 20mTorr.
[0059] In step S206, the target hard mask is removed using a wet etching solution to obtain the target grating. Wet etching is a micro-nanofabrication technology that achieves selective material removal by reacting a chemical solution with the material surface. The choice of wet etching solution depends on the properties of the material to be etched and the process requirements. Wet etching solutions can include hydrofluoric acid, phosphoric acid, nitric acid, etc. In actual applications, the choice should be based on the actual application situation. This application does not impose any restrictions in this regard.
[0060] Figure 3 FIG1 shows a schematic diagram of a structure in which a material to be etched is deposited on a grating substrate in a first embodiment of a grating manufacturing method according to an embodiment of the present application. Figure 4 FIG1 shows a schematic diagram of the structure after etching the material to be etched to obtain the film layer to be etched in the first embodiment of the grating manufacturing method of the embodiment of the present application. Figure 5 FIG1 shows a schematic diagram of a structure after depositing a hard mask layer on a film layer to be etched and spin-coating an imprinting adhesive mask layer on the hard mask layer in a first embodiment of a grating manufacturing method according to an embodiment of the present application. Figure 6 FIG1 shows a schematic structural diagram of a first embodiment of the grating manufacturing method according to an embodiment of the present application after the grating structure pattern is embossed on the embossed adhesive mask layer. Figure 7 A schematic diagram of the structure after etching the exposed hard mask layer after imprinting, removing the imprinted adhesive mask layer, and etching the film layer to be etched based on the obtained target hard mask in the first embodiment of the grating manufacturing method of the present application is shown. Figure 8 FIG1 shows a schematic diagram of the structure of the target grating obtained after removing the target hard mask in the first embodiment of the grating manufacturing method of the present application. Figures 3 to 8 In the first embodiment, as Figure 3 As shown in Figure 1, a 300 nm thick TiO2 layer can be deposited on a glass substrate using plasma enhanced chemical vapor deposition. Figure 4 As shown, after coating, exposure and development, TiO2 is etched into TiO2 film layers with surface heights of 100nm, 200nm and 300nm respectively. Figure 5As shown, 30nm of Cr (chromium) is deposited on the TiO2 film to be etched by physical vapor phase to form a hard mask layer, and a stamping resin mask layer is spin-coated on the hard mask layer. Figure 6 As shown, a grating structure pattern is embossed on the imprinted mask layer. The pattern is a straight tooth pattern with a grating period (grating period refers to the distance between two adjacent teeth (or grooves) in the grating structure) of 310nm, a duty cycle (duty cycle refers to the ratio of the grating line width to the grating period) of 27%, a line width (line width refers to the width of each tooth (or groove) in the grating structure) of 84nm, and a line spacing (line spacing refers to the distance between two adjacent teeth (or grooves) in the grating structure) of 226nm. Figure 7 As shown, further, the exposed hard mask layer Cr after imprinting is etched by chemical reaction gas to obtain a target hard mask, and the imprinted adhesive mask layer is removed by wet method, and further, with the target hard mask as a shield, the film layer to be etched is etched by an inductively coupled plasma (ICP) etching machine, and the preset mixed gas for etching is a mixed gas of chlorine and octafluorocyclobutane, and the target etching depths are 100nm, 200nm, and 300nm, respectively, that is, the target etching depth at a position with a surface height of 100nm is 100nm, the target etching depth at a position with a surface height of 200nm is 200nm, and the target etching depth at a position with a surface height of 300nm is 300nm, that is, the target etching position is etched until the etching depth reaches the glass substrate. Figure 8 As shown, after the target hard mask is removed by wet etching solution, TiO2 straight tooth gratings with surface heights of 100nm, 200nm, and 300nm are finally obtained.
[0061] Figure 9 10 shows a schematic diagram of the structure of depositing a material to be etched on a grating substrate in the second embodiment of the grating manufacturing method according to the embodiment of the present application. 11 shows a schematic diagram of the structure of the second embodiment of the grating manufacturing method according to the embodiment of the present application after etching the material to be etched to obtain a film layer to be etched. Figure 11 FIG2 shows a schematic structural diagram of a second embodiment of the grating fabrication method according to an embodiment of the present application, after a hard mask layer is deposited on the film layer to be etched and an imprinting adhesive mask layer is spin-coated on the hard mask layer. Figure 12 FIG2 shows a schematic structural diagram of a second embodiment of the grating manufacturing method according to an embodiment of the present application after the grating structure pattern is embossed on the embossing mask layer. Figure 13A schematic diagram of the structure after etching the exposed hard mask layer after imprinting, removing the imprinted adhesive mask layer, and etching the film layer to be etched based on the obtained target hard mask in the second embodiment of the grating manufacturing method of the present invention is shown. Figure 14 FIG2 shows a schematic diagram of the structure of the target grating obtained after removing the target hard mask in the second embodiment of the grating manufacturing method of the embodiment of the present application. Figures 9 to 14 In the second embodiment, as Figure 9 As shown in Figure 1, a 500nm thick TiO2 layer can be deposited on a glass substrate using plasma enhanced chemical vapor deposition. Figure 10 As shown, TiO2 is etched into a TiO2 film layer to be etched with a surface height gradient of 0-500nm. Figure 11 As shown, 30nm of Cr (chromium) is deposited on the TiO2 film to be etched by physical vapor phase to form a hard mask layer, and a stamping resin mask layer is spin-coated on the hard mask layer. Figure 12 As shown, a grating structure pattern is embossed on the embossed mask layer, and the pattern is a straight tooth pattern with a grating period of 402nm, a duty cycle of 40%, a line width of 160nm, and a line spacing of 242nm. Figure 13 As shown, the exposed hard mask layer Cr after imprinting is further etched by chemical reaction gas to obtain a target hard mask, and the imprinted adhesive mask layer is wet removed. Furthermore, the target hard mask is used as a shield to etch the film layer to be etched by an inductively coupled plasma (ICP) etching machine. The preset mixed gas for etching is a mixed gas of chlorine and octafluorocyclobutane. The target etching depth is a gradient depth of 0-500nm, that is, the target etching position is etched until the etching depth reaches the glass substrate. Figure 14 As shown, after the target hard mask is removed by wet etching solution, a TiO2 straight tooth grating with a surface height gradient of 0-500nm is finally obtained.
[0062] Although multiple embodiments of the present application have been shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art can conceive of many changes, modifications, and alternatives without departing from the thought and spirit of the present application. It should be understood that in the process of practicing the present application, various alternatives to the embodiments of the present application described herein can be adopted. The accompanying claims are intended to define the scope of protection of the present application and therefore cover equivalents or alternatives within the scope of these claims.
Claims
1. A grating manufacturing method, characterized in that: include: depositing a material to be etched on the grating substrate; Etching the material to be etched based on the preset grating height at each position on the material to be etched to obtain a film layer to be etched; Depositing a hard mask layer on the film layer to be etched, and spin-coating an imprinting adhesive mask layer on the hard mask layer; Imprinting a grating structure pattern on the imprinted adhesive mask layer, and etching the hard mask layer exposed after the imprinting to obtain a target hard mask; removing the imprinted adhesive mask layer, and etching the film layer to be etched based on the target hard mask; The target hard mask is removed to obtain a target grating.
2. The grating manufacturing method according to claim 1, characterized in that: The etching of the material to be etched based on the preset grating height at each position on the material to be etched comprises: The material to be etched is etched according to a preset grating height at each position on the material to be etched by a gas cluster ion beam etching machine or a reactive ion beam etching machine.
3. The grating manufacturing method according to claim 1, characterized in that: The etching of the exposed hard mask layer after imprinting comprises: The hard mask layer exposed after imprinting is etched by chemical reaction gas; wherein the chemical reaction gas is any one of fluorine-based gas, chlorine-based gas and a mixed gas of the fluorine-based gas and the chlorine-based gas.
4. The grating manufacturing method according to claim 1, wherein: The removing of the embossing adhesive mask layer comprises: The embossing resin mask layer is removed by dry resist or wet resist stripping.
5. The grating manufacturing method according to claim 1, characterized in that: The etching of the film layer to be etched based on the target hard mask includes: The target hard mask is used as a shield to etch the film layer to be etched by an inductively coupled plasma etching machine.
6. The grating manufacturing method according to claim 5, characterized in that: The etching of the film to be etched by using an inductively coupled plasma etching machine includes: In the inductively coupled plasma etching machine, each target etching position of the film layer to be etched is etched by using a preset mixed gas until each target etching position reaches a corresponding target etching depth.
7. The grating manufacturing method according to claim 6, characterized in that: The preset mixed gas is a mixed gas of chlorine and octafluorocyclobutane, and the gas ratio of the chlorine to the octafluorocyclobutane is between 2:1 and 8:1; The power range of the inductively coupled plasma etching machine is 2500w / 200MHz to 1500w / 400MHz; The chamber pressure of the inductively coupled plasma etching machine ranges from 10 mTorr to 20 mTorr.
8. The grating manufacturing method according to claim 1, wherein: The removing of the target hard mask comprises: The target hard mask is removed by using a wet etching solution.
9. The grating manufacturing method according to claim 1, characterized in that: The step of depositing the material to be etched on the grating substrate comprises: Any one of TiO2, Si, SiO2, SiN and Nb2O5 is deposited on the grating substrate.
10. The grating manufacturing method according to claim 1, wherein: Depositing a hard mask layer on the film layer to be etched includes: Any one of Cr, TiN, Al and Cu is deposited on the film layer to be etched.
11. An optical waveguide product, characterized in that: include: The grating is manufactured using the grating manufacturing method according to any one of claims 1 to 10.