Optical glasses internal triangular grating structure and manufacturing method thereof

Abstract

The application discloses an optical glasses internal triangular grating structure and a manufacturing method thereof. The method comprises the following steps: forming an embossing glue pattern on a non-metal mask layer located on a functional layer and performing a first treatment to remove burrs; forming a first mask pattern on the functional layer through the embossing glue pattern and performing a second treatment to form a first oxide layer; forming a smooth side wall structure on both sides of the first mask pattern to form a second mask pattern; etching the functional layer through the second mask pattern until the first oxide layer is completely etched and consumed; repeating the process of forming the second mask pattern and etching the functional layer until the first mask pattern is completely etched and consumed; and forming a plurality of smooth triangular grating structures on the functional layer. The application can reduce the process difficulty, realize the smooth processing of the side wall, be suitable for enhancing the optical performance, improving the diffraction efficiency and long-term stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of precision manufacturing of semiconductor optical devices, and in particular to an internal triangular grating structure of optical glasses and a manufacturing method thereof. BACKGROUND

[0002] At present, when a triangular grating structure in optical glasses is manufactured by using a conventional etching process, it is difficult to pattern the triangular grating structure, and the side wall surface of the grating groove obtained often presents a pitted and pocky appearance with obvious undulations, and the surface roughness of the inclined side wall of the grating groove after etching is often high (Ra>100nm), resulting in problems of large light scattering loss and reduced diffraction efficiency. Therefore, it is necessary to study a new manufacturing technology of an internal triangular grating structure of optical glasses to enhance optical performance, improve diffraction efficiency and long-term stability. SUMMARY

[0003] The present application aims to overcome the above-mentioned problems existing in the prior art, and provides an internal triangular grating structure of optical glasses and a manufacturing method thereof, so as to optimize the patterning process of the triangular grating structure and realize smooth processing of the side wall, thereby being suitable for enhancing optical performance, improving diffraction efficiency and long-term stability.

[0004] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0005] According to a first aspect of the present application, the present application provides a manufacturing method of an internal triangular grating structure of optical glasses, which comprises the following steps in sequence:

[0006] (a) forming a non-metal mask layer on a functional layer;

[0007] (b) forming a plurality of triangular imprint glue patterns on the non-metal mask layer;

[0008] (c) using a first process gas to perform a first treatment on the surface of the imprint glue pattern to remove burrs;

[0009] (d) performing etching patterning on the non-metal mask layer through the imprint glue pattern to form a plurality of triangular first mask patterns on the functional layer;

[0010] (e) using a second process gas to perform a second treatment on the surface of the first mask pattern to form a first oxide layer;

[0011] (f) using an atomic layer deposition process to form a second oxide layer on the surface of the first mask pattern;

[0012] (g) performing a back-etching on the second oxide layer to form a side wall structure with smooth surface on both sides of the first mask pattern, the first mask pattern, the first oxide layer and the side wall structure form a second mask pattern with smooth side surface;

[0013] (h) performing an etching on the exposed surface of the functional layer through the second mask pattern until the first oxide layer is completely etched and consumed;

[0014] repeating (e) to (h) until the first mask pattern is completely etched and consumed, and a plurality of triangular grating structures are formed on the functional layer under the first mask pattern, and the smooth side surface of the second mask pattern is transferred to the two side walls of the grating structure through pattern transfer.

[0015] In some embodiments, the functional layer is disposed on a substrate, and the substrate comprises a glass substrate.

[0016] In some embodiments, the functional layer comprises a titanium dioxide layer.

[0017] In some embodiments, the non-metal mask layer comprises a polysilicon layer.

[0018] In some embodiments, the first oxide layer comprises a silicon dioxide layer.

[0019] In some embodiments, the second oxide layer comprises a silicon dioxide layer.

[0020] In some embodiments, when (b) is performed, it specifically comprises:

[0021] spinning an ultraviolet-curable imprint glue on the non-metal mask layer;

[0022] pressing a transparent soft template with a preset triangular grating pattern on the non-metal mask layer coated with the ultraviolet-curable imprint glue, and curing the ultraviolet-curable imprint glue by ultraviolet irradiation under a pressure of 1 mTorr to 500 mTorr, so as to copy the preset triangular grating pattern on the transparent soft template to the ultraviolet-curable imprint glue, and after demolding, forming an imprint glue pattern with a vertical cross section of a triangle on the non-metal mask layer.

[0023] In some embodiments, when (b) is performed, it specifically comprises:

[0024] spinning a heat-curable imprint glue on the non-metal mask layer;

[0025] A hard template with a preset triangular grating pattern is pressed on the non-metal mask layer coated with the thermally-curable imprint glue, and the thermally-curable imprint glue is cured by heating under a pressure of 1 mTorr-500 mTorr, so that the preset triangular grating pattern on the hard template is copied to the thermally-curable imprint glue, and after demolding, an imprint glue pattern with a vertical cross section of a triangle is formed on the non-metal mask layer.

[0026] In some embodiments, when performing (c), the first process gas comprises O2, the temperature is 60-100°C, the pressure is 5-50 mTorr, the source power is 500-1000 W, and the bias power is 0-200 W.

[0027] In some embodiments, the first treatment is performed by exciting O2 to form an O2 plasma, and filtering charged particles in the O2 plasma to obtain O radicals.

[0028] In some embodiments, when performing (e), the second process gas comprises O2, and the second treatment is performed by exciting O2 to form an O2 plasma, and filtering charged particles in the O2 plasma to obtain O radicals, the temperature is 150-200°C, the pressure is 500 mTorr-1 Torr, the source power is 1000-2000 W, and the bias power is turned off.

[0029] In some embodiments, when performing (e), the second process gas comprises O2, and the second treatment is performed by a thermal oxidation process, the temperature is 500-1000°C, and the time is 5-60 s.

[0030] In some embodiments, a dry etching process is used to pattern the non-metal mask layer, the process gas comprises Cl2, HBr, SF6 and O2, the dilution and dissociation gas comprises at least one of N2 and Ar, the temperature is -10-20°C, the pressure is 5-100 mTorr, the source power is 100-1000 W, and the bias power is 5-100 W.

[0031] In some embodiments, when performing the atomic layer deposition process, the temperature is 600-800°C, the pressure is 100-5000 mTorr, the silicon source precursor comprises SiH4 or tetraethyl orthosilicate, and the oxygen source comprises at least one of N2O, O2 and O3.

[0032] In some embodiments, the second oxide layer is etched back by a dry etching process, the process gas includes CF4, C4F8, NF3 and O2, the dilution and dissociation gas includes at least one of N2 and Ar, the temperature is 0-80℃, the pressure is 5-500mTorr, the source power is 500-1000W, and the bias power is 50-500W.

[0033] In some embodiments, the exposed surface of the functional layer is etched by a dry etching process, the process gas includes Cl2, CH4, HBr and O2, the dilution and dissociation gas includes at least one of N2, Ar and He, the temperature is 0-60℃, the pressure is 1-1Torr, the source power is 50-3000W, and the bias power is 50-200W.

[0034] According to a second aspect of the present application, the embodiments of the present application further provide an internal triangular grating structure of optical glasses, which is obtained by using the manufacturing method of the internal triangular grating structure of optical glasses provided by any one of the embodiments of the present application.

[0035] The embodiments of the present application can have / possess at least the following advantages:

[0036] (1) The embodiments of the present application define the mask topography of the triangular grating pattern in advance by forming the triangular imprint glue pattern, and repeatedly perform the process of forming the first oxide layer, the second oxide layer, the side wall structure and etching the functional layer when etching the functional layer to form the triangular grating structure, which not only can utilize the continuous consumption of the first mask pattern in the etching process to continuously transfer the triangular topography to the functional layer to form a grating structure with the same triangular vertical section, thereby optimizing the patterning process of the triangular grating structure, but also can make the smooth side of the second mask pattern transferred to the two side walls of the grating structure by pattern transfer, thereby achieving the smooth processing of the side wall, so as to be applicable to enhance the optical performance, improve the diffraction efficiency and long-term stability during use.

[0037] (2) The embodiment of the present application can remove burrs and other defects existing on the surface of the imprint glue pattern, reduce the surface roughness, and improve the surface quality, thereby improving the triangular morphology precision of the first mask pattern formed by etching the non-metal mask layer through the imprint glue pattern; the first mask pattern surface is treated by the second treatment to form a first oxide layer, which can improve the roughness defects existing on the surface of the first mask pattern to preliminarily reduce the surface roughness; the second oxide layer is formed on the surface of the first mask pattern by using an atomic layer deposition process, which can further fill the roughness defects on the surface of the first mask pattern layer by layer at the atomic level and realize the atomic level surface flatness; the second oxide layer is etched back to form a side wall structure with a smooth surface on the two sides of the triangular side of the first mask pattern, which significantly improves the smoothness of the overall side wall of the second mask pattern. Therefore, when the triangular grating structure is formed by etching the exposed surface of the functional layer through the second mask pattern, the smooth side surface of the second mask pattern can be transferred to the side wall surface of the grating structure through pattern transfer, and a grating structure with a smooth side wall is obtained. Therefore, the embodiment of the present application can effectively solve the problem that it is difficult to pattern the triangular grating structure in the conventional etching process for manufacturing optical glasses, which causes poor side wall roughness and leads to large light scattering loss and low diffraction efficiency.

[0038] (3) The embodiment of the present application can use O radicals to gently perform the first treatment on the surface of the imprint glue pattern, which can effectively remove burrs while avoiding damage to the triangular morphology of the imprint glue pattern, thereby helping to maintain the sharp corner characteristics of the triangular top corner of the imprint glue pattern and improving the pattern transfer quality. By using O radicals, the surface of the first mask pattern can be gently treated by the second treatment, a dense first oxide layer is formed, a good treatment bottom surface is formed on the surface of the first mask pattern, thereby laying a foundation for further forming a second oxide layer on the oxidized surface of the first mask pattern and realizing atomic level surface flatness.

[0039] (4) The embodiment of the present application can realize uniform treatment of the overall side wall of the grating structure during the preparation of the grating structure, which can reduce the side wall roughness from the existing Ra greater than 100 nm to the level of Ra 1 nm-10 nm, thereby improving the precision of the device.

[0040] (5) The embodiment of the present application uses a first mask pattern made of polycrystalline silicon, and a first oxide layer and a side wall structure formed of silicon dioxide to form a second mask pattern, which avoids the problem of metal byproduct pollution caused by using a metal mask, thereby improving the reliability of the device.

[0041] Other advantages of the present application will be described in the following detailed description of the application. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 A flow chart of a method for manufacturing an internal triangular grating structure of an optical eyeglass according to an embodiment of the present application.

[0043] Figure 2 A structure diagram after forming a triangular imprinting glue pattern on a surface of a non-metal mask layer according to an embodiment of the present application.

[0044] Figure 3 A structure diagram after forming a triangular first mask pattern on a functional layer according to an embodiment of the present application.

[0045] Figure 4 A structure diagram after forming a side wall structure on a side of the first mask pattern according to an embodiment of the present application.

[0046] Figure 5 A structure diagram after etching the functional layer to form a trench intermediate structure according to an embodiment of the present application.

[0047] Figure 6 A structure diagram after forming a side wall structure on a side of the first mask pattern again according to an embodiment of the present application.

[0048] Figure 7 A structure diagram after etching the functional layer to form a grating intermediate structure according to an embodiment of the present application.

[0049] Figure 8 A structure diagram after forming a triangular grating structure on the functional layer according to an embodiment of the present application.

[0050] Fig. 10. functional layer; 11. non-metal mask layer; 111. first mask pattern; 12. imprinting glue pattern; 13. opening; 14. side wall structure; 141. second oxide layer; 15. trench intermediate structure; 16. grating intermediate structure; 17. grating structure; 100. substrate. DETAILED DESCRIPTION

[0051] In order to solve the problem that, in the prior art, when a triangular grating structure is manufactured in an optical glasses by using a conventional etching process, it is difficult to pattern the triangular grating structure, the sidewall surface of the grating groove is rough, has obvious undulation, and the surface roughness of the inclined sidewall of the grating groove is high (Ra>100 nm) after etching, which leads to large light scattering loss and reduced diffraction efficiency, embodiments of the present application provide a manufacturing method of a triangular grating structure in an optical glasses, which comprises the following steps in sequence:

[0052] (a) forming a non-metal mask layer on a functional layer;

[0053] (b) forming a plurality of triangular imprint glue patterns on the non-metal mask layer;

[0054] (c) performing first processing on the surface of the imprint glue pattern by using a first process gas, so as to remove burrs;

[0055] (d) performing etching patterning on the non-metal mask layer by using the imprint glue pattern, so as to form a plurality of triangular first mask patterns on the functional layer;

[0056] (e) performing second processing on the surface of the first mask pattern by using a second process gas, so as to form a first oxide layer;

[0057] (f) forming a second oxide layer on the surface of the first mask pattern by using an atomic layer deposition process;

[0058] (g) performing back etching on the second oxide layer, so as to form a sidewall structure with smooth surface on the two side surfaces of the first mask pattern, and the first mask pattern, the first oxide layer and the sidewall structure form a second mask pattern with smooth side surface;

[0059] (h) performing etching on the exposed surface of the functional layer by using the second mask pattern, until the first oxide layer is completely etched and consumed;

[0060] repeating steps (e) to (h) until the first mask pattern is completely etched and consumed, and a plurality of triangular grating structures are formed on the functional layer under the first mask pattern, and the smooth side surface of the second mask pattern is transferred to the two sidewalls of the grating structure by pattern transfer.

[0061] The embodiments of the present application also provide a triangular grating structure in an optical glasses, which is obtained by using the manufacturing method of the triangular grating structure in the optical glasses.

[0062] The embodiment of the present application forms a triangular imprint glue pattern, defines a mask topography of a triangular grating pattern in advance, and forms a first oxide layer, a second oxide layer, a side wall structure and a functional layer etching process through repeated cycles when forming a triangular grating structure, which not only uses the first mask pattern to continuously transfer the triangular topography to the functional layer during the etching process, forms a grating structure with a triangular vertical section, optimizes the patterning process of the triangular grating structure, and makes the smooth side of the second mask pattern formed by pattern transfer to the two side walls of the grating structure, thereby achieving smooth processing of the side wall, and thus can be applied to enhance optical performance, improve diffraction efficiency and long-term stability during use.

[0063] The specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0064] Reference Figure 1 The embodiment of the present application provides a manufacturing method of an internal triangular grating structure of an optical glasses, which comprises the following steps in sequence:

[0065] Step S11: providing a substrate with a functional layer and a non-metal mask layer.

[0066] Reference Figure 2 In some embodiments, the surface of the substrate 100 is sequentially provided with the functional layer 10 and the non-metal mask layer 11.

[0067] In some embodiments, the substrate 100 comprises a glass substrate. The glass substrate material can be, for example, silicon dioxide (SiO2). But it can not be limited to this.

[0068] In some embodiments, the functional layer 10 comprises a titanium dioxide layer. For example, the material of the functional layer 10 is titanium dioxide (TiO2). But it can not be limited to this.

[0069] The functional layer 10 is used to manufacture a grating structure with a triangular vertical section to manufacture a triangular grating structure inside the optical glasses.

[0070] In some embodiments, a deposition process is used to form a titanium dioxide layer on the surface of the substrate 100 as the functional layer 10.

[0071] In some embodiments, the non-metal mask layer 11 comprises a polysilicon layer. For example, the material of the non-metal mask layer 11 is polysilicon. But it can not be limited to this. The non-metal mask layer 11 is used to form a mask for etching and patterning the functional layer 10.

[0072] In some embodiments, a deposition process is used to form a polysilicon layer on the surface of the functional layer 10 as the non-metal mask layer 11.

[0073] Step S12: Forming a triangular imprinting glue pattern on the non-metal mask layer.

[0074] In some embodiments, a spin coating process is adopted to form an imprinting glue layer on the surface of the non-metal mask layer 11. The imprinting glue of the imprinting glue layer can be a UV-curable imprinting glue or a thermal-curable imprinting glue.

[0075] Then, a template (not shown) with a preset triangular grating pattern is aligned and pressed against the surface of the imprinting glue layer, and a imprinting process is adopted to pattern the imprinting glue layer, so as to copy the grating pattern with triangular vertical cross-section on the template to the imprinting glue layer. After demolding, a plurality of periodically arranged triangular imprinting glue patterns 12 with triangular vertical cross-section are formed on the surface of the non-metal mask layer 11, as shown in FIG. 1C. Figure 2

[0076] In some embodiments, the definition process of the imprinting glue pattern 12 can specifically include:

[0077] First, a UV-curable imprinting glue is spin coated on the surface of the non-metal mask layer 11. Then, a transparent soft template with a preset triangular grating pattern is pressed against the non-metal mask layer 11 coated with the UV-curable imprinting glue, and the UV-curable imprinting glue is cured by UV irradiation under a pressure of 1 mTorr to 500 mTorr, so as to copy the preset triangular grating pattern on the transparent soft template to the UV-curable imprinting glue. After demolding, the imprinting glue pattern 12 with triangular vertical cross-section is formed on the surface of the non-metal mask layer 11.

[0078] In some embodiments, the definition process of the imprinting glue pattern 12 can specifically include:

[0079] First, a thermal-curable imprinting glue is spin coated on the surface of the non-metal mask layer 11. Then, a hard template with a preset triangular grating pattern is pressed against the non-metal mask layer 11 coated with the thermal-curable imprinting glue, and the thermal-curable imprinting glue is cured by heating under a pressure of 1 mTorr to 500 mTorr, so as to copy the preset triangular grating pattern on the hard template to the thermal-curable imprinting glue. After demolding, the imprinting glue pattern 12 with triangular vertical cross-section is formed on the non-metal mask layer 11.

[0080] Step S13: Performing a first treatment on the surface of the imprinting glue pattern.

[0081] Reference Figure 2 In some embodiments, a first process gas is adopted to perform a first treatment on the surface of the imprinting glue pattern 12 formed in the above step, so as to remove burrs and other defects such as residues existing on the surface of the imprinting glue pattern 12.

[0082] ​In some embodiments, when performing the first treatment, the first process gas comprises O2, the dilution and dissociation gas comprises N2, the temperature is 60-100°C, the pressure is 5-50 mTorr, the source power is 500-1000 W, and the bias power is 0-200 W.

[0083] In some embodiments, when performing the first treatment, the O2 plasma is formed by exciting O2, and charged particles in the O2 plasma are filtered out to obtain O radicals (oxygen radicals) for treating and removing defects such as burrs and residues present on the surface of the photoresist pattern 12.

[0084] By performing the first treatment on the surface of the photoresist pattern 12, the surface roughness of the photoresist pattern 12 can be reduced, and the surface quality of the photoresist pattern 12 can be improved, thereby improving the pattern accuracy when subsequently etching and patterning the non-metal mask layer 11 by using the photoresist pattern 12 to form a triangular first mask pattern.

[0085] Step S14: etching and patterning the non-metal mask layer by using the photoresist pattern to form a triangular first mask pattern.

[0086] Reference Figure 3 In some embodiments, the non-metal mask layer 11 is etched and patterned by using the photoresist pattern 12 as a mask, and the triangular pattern features of the photoresist pattern 12 are transferred to the non-metal mask layer 11 to form a plurality of periodically arranged triangular first mask patterns 111 on the surface of the functional layer 10, i.e., the first mask patterns 111 have a triangular vertical cross section.

[0087] In some embodiments, the plurality of periodically arranged first mask patterns 111 of the polycrystalline silicon material are used as a mask for subsequent etching of the functional layer 10, and an opening 13 serving as an etching window is formed between adjacent two first mask patterns 111 to expose the surface of the functional layer 10 between the adjacent first mask patterns 111.

[0088] In some embodiments, the non-metal mask layer 11 is etched and patterned by using a dry etching process, the process gas comprises Cl2, HBr, SF6, and O2, the dilution and dissociation gas comprises at least one of N2 and Ar, the temperature is -10-20°C, the pressure is 5-100 mTorr, the source power is 100-1000 W, and the bias power is 5-100 W. However, the present application is not limited thereto.

[0089] Reference Figure 3 In some embodiments, a third process gas is used to perform a third treatment on the surface of the first mask pattern 111 to clean the surface of the first mask pattern 111.

[0090] In some embodiments, when performing the third processing, the third process gas includes O2, the dilution and dissociation gas includes at least one of N2and He, and the ion filter is turned on. The surface of the first mask pattern 111 of the polysilicon material is cleaned by forming a plasma of O2from the excited O2and removing the charged particles in the plasma of O2to obtain oxygen radicals.

[0091] In some embodiments, when performing the third processing, the temperature is 150-250°C, the pressure is 100 mTorr-1 Torr, the source power is 500-3000 W, and the bias power is turned off. However, the present application is not limited thereto.

[0092] The surface of the first mask pattern 111 is gently cleaned by using the oxygen radicals, which avoids damaging the surface of the first mask pattern 111, is beneficial to maintaining the sharp corner feature of the triangular top corner of the first mask pattern 111, and avoids aggravating the roughness of the surface of the first mask pattern 111 to form a good processing bottom surface on the surface of the first mask pattern 111, thereby laying a foundation for the subsequent surface oxidation processing of the first mask pattern 111 to form the first oxide layer and further forming the second oxide layer on the oxidized surface of the first mask pattern 111 to realize atomic-level surface flatness.

[0093] Step S15: performing second processing on the surface of the first mask pattern to form a first oxide layer.

[0094] Reference Figure 3 In some embodiments, the second process gas is used to perform the second processing on the surface of the first mask pattern 111 to form a first oxide layer (not shown) on the surface of the first mask pattern 111.

[0095] In some embodiments, the first oxide layer includes a silicon dioxide layer. For example, the material of the first oxide layer is silicon dioxide.

[0096] In some embodiments, when performing the second processing, the second process gas includes O2, a plasma of O2is formed from the excited O2, and the charged particles in the plasma of O2are removed to obtain oxygen radicals, and the surface of the first mask pattern 111 is gently oxidized to form a dense first oxide layer. When performing the second processing, the temperature is 150-200°C, the pressure is 500 mTorr-1 Torr, the source power is 1000-2000 W, and the bias power is turned off. However, the present application is not limited thereto.

[0097] In some embodiments, the surface of the first mask pattern 111 is subjected to a second treatment by a thermal oxidation process to form a compact first oxide layer on the surface of the first mask pattern 111. In the thermal oxidation process, the second process gas includes O2 (dry oxygen) or O2 and H2 (wet oxygen synthesis), and N2 is used as the carrier gas or dilution gas, the temperature is 500-1000°C, the time is 5-60s, and the pressure is normal pressure. However, the present application is not limited thereto.

[0098] By subjecting the surface of the first mask pattern 111 to the second treatment, the first oxide layer is formed on the surface of the first mask pattern 111, which can improve the rough defects existing on the surface of the first mask pattern 111, and preliminarily reduce the surface roughness, thereby laying a foundation for further forming the second oxide layer on the oxidized surface of the first mask pattern 111 and achieving atomic-level surface flatness.

[0099] Step S16: Forming a second oxide layer on the surface of the first mask pattern and forming a side wall structure by etching back to form a second mask pattern.

[0100] Reference Figure 4 In some embodiments, the atomic layer deposition process is used to form a plurality of second oxide layers 141 on the surface of the first mask pattern 111, i.e., on the left and right two sides of the triangular shape of the first mask pattern 111, to further fill the rough defects existing on the surface of the first mask pattern 111 at the atomic level layer by layer, and to sufficiently maintain the triangular shape of the first mask pattern 111. Finally, the rough surfaces with different depths existing on the side of the first mask pattern 111 are filled and flattened, so that the sidewall of the first mask pattern 111 reaches the atomic-level flatness, and the repair of the sidewall roughness of the first mask pattern 111 is achieved.

[0101] In some embodiments, the second oxide layer 141 includes a silicon dioxide layer. For example, the material of the second oxide layer 141 is silicon dioxide.

[0102] In some embodiments, the atomic layer deposition process is performed at a temperature of 600-800°C and a pressure of 100-5000mTorr, the silicon source precursor includes SiH4 or tetraethyl orthosilicate, and the oxygen source includes at least one of N2O, O2, and O3.

[0103] Then, the second oxide layer 141 formed in the previous step is etched back to form a smooth side wall structure 14 on the two side surfaces of the first mask pattern 111. The first mask pattern 111, the first oxide layer, and the side wall structure 14 form a second mask pattern with smooth side surfaces.

[0104] The side wall structure 14 is formed on both sides of the first mask pattern 111 to improve the smoothness of the side surface of the second mask pattern. When the exposed surface of the functional layer 10 is etched to form a triangular grating structure through the second mask pattern, the smooth side surface of the second mask pattern is transferred to the side wall surface of the grating structure, and a grating structure with smooth side wall is obtained, thereby reducing the surface roughness of the grating groove side wall.

[0105] When the second oxide layer 141 is etched back, the second oxide layer 141 on the surface of the functional layer 10 is etched and removed to expose the surface of the functional layer 10, and at least the second oxide layer 141 on the bottom of the side surface of the first mask pattern 111 is effectively retained. In this way, even if the second oxide layer 141 on the top of the first mask pattern 111 is partially removed during etching back, the exposed top side surface of the first mask pattern 111 is also smooth due to the characteristics of the etching back process. Figure 4 An example of the side wall structure 14 formed after etching back covering the two sides of the first mask pattern 111 is shown.

[0106] In some embodiments, the second oxide layer 141 is etched back by a dry etching process, the process gas includes CF4, C4F8, NF3 and O2, the dilution and dissociation gas includes at least one of N2 and Ar, the temperature is 0-80°C, the pressure is 5-500 mTorr, the source power is 500-1000 W, and the bias power is 50-500 W. However, it is not limited thereto.

[0107] Step S17: Etching the exposed surface of the functional layer through the second mask pattern until the first oxide layer is completely etched and consumed.

[0108] Reference Figure 5 In some embodiments, a plasma dry etching process is used, and the exposed surface of the functional layer 10 in the opening 13 between adjacent second mask patterns is etched downward through the second mask pattern to form a groove intermediate structure 15 with a certain depth in the functional layer 10, and the smooth surface of the side wall structure 14 is transferred to the side wall of the groove intermediate structure 15 through pattern transfer, thereby forming a groove intermediate structure 15 with smooth side wall in the functional layer 10, and etching to the first oxide layer is completely etched and consumed until the surface of the first mask pattern 111 is exposed.

[0109] In some embodiments, when etching the exposed surface of the functional layer 10, the process gas includes Cl2, CH4, HBr and O2, the dilution and dissociation gas includes at least one of N2, Ar, He, the temperature is 0-60℃, the pressure is 1mTorr-1Torr, the source power is 50-3000W, and the bias power is 50-200W. But it is not limited thereto.

[0110] Step S18: repeat the execution of steps S15-S17 until the first mask pattern is completely etched and consumed, and a side wall smooth triangular grating structure is formed on the functional layer.

[0111] In some embodiments, when the side wall structure 14 and the first oxide layer are etched and consumed in step S17, the steps S15-S17 are repeatedly executed, i.e., the second processing of the surface of the first mask pattern 111 is performed again to form the first oxide layer, the second oxide layer 141 is formed on the surface of the first mask pattern 111, and the side wall structure 14 is formed by etching back to form a second mask pattern, as shown in Figure 6 , and the exposed surface of the functional layer 10 is continuously etched with the second mask pattern as a mask to further form the grating intermediate structure 16 in the functional layer 10 (i.e., a new groove intermediate structure with increased length of the side wall between adjacent grating intermediate structures 16), as shown in Figure 7 , and in the process of repeated etching, the first mask pattern 111 itself will also be gradually etched and consumed (see Figure 7 ), until the first mask pattern 111 is completely etched and consumed in the etching process, and a plurality of periodically arranged triangular grating structures 17 evolved from the grating intermediate structures 16 are formed on the functional layer 10 below the first mask pattern 111, so that the formed grating structure 17 has a triangular vertical cross section (i.e., the grating structure 17 has a triangular cross section in the vertical direction perpendicular to the horizontal surface of the functional layer 10), as shown in Figure 8 .

[0112] And, at each cycle, a first oxide layer can be formed by surface oxidation treatment (second treatment) on the first mask pattern 111, and a second oxide layer 141 can be formed on the surface of the first mask pattern 111 to repair the roughness of the sidewall of the first mask pattern 111, and by forming a smooth-surface sidewall structure 14 on both sides of the first mask pattern 111, the smooth surface of the sidewall structure 14 can be transferred to the sidewall of the trench intermediate structure 15 (or the grating intermediate structure 16) at each repetition of etching the functional layer 10, so that the smooth surface of the sidewall structure 14 can be continuously transferred by pattern transfer, and transferred to the two sidewalls of the triangle of the grating structure 17 finally formed, thereby forming a triangle grating structure 17 with smooth sidewalls.

[0113] In some embodiments, after the process of forming the triangle grating structure 17 with smooth sidewalls is completed, the substrate 100 is thoroughly rinsed with a large amount of ultra-pure water (DIW) to completely terminate the chemical reaction and remove all chemical residues. The subsequent drying step adopts high-speed spin drying or isopropyl alcohol (IPA) vapor drying method to avoid water marks.

[0114] The embodiment of the present application defines the mask topography of the triangle grating pattern in advance by forming the triangle imprint glue pattern 12, and by repeatedly performing the process of forming the first oxide layer, the second oxide layer 141, the sidewall structure 14, and etching the functional layer 10 when etching the functional layer 10 to form the triangle grating structure 17, not only can the first mask pattern 111 be continuously consumed during etching to transfer the triangle topography to the functional layer 10, forming a grating structure 17 with the same triangle vertical section, thereby optimizing the patterning process of the triangle grating structure, but also the smooth topography of the side of the second mask pattern formed can be transferred to the two sidewalls of the grating structure 17 formed by pattern transfer, thereby realizing the smooth processing of the sidewall, so as to be applicable to enhance the optical performance, improve the diffraction efficiency and long-term stability in use.

[0115] The embodiment of the present application can realize uniform processing of the entire sidewall of the grating structure 17 during the preparation of the grating structure 17, so that the sidewall roughness can be reduced from the existing Ra greater than 100 nm to the level of Ra 1 nm-10 nm, thereby improving the precision of the device.

[0116] In some embodiments, the etching depth is 1 nm-100 nm each time the functional layer 10 is etched in step S17.

[0117] In some embodiments, whether the first oxide layer material (silicon oxide) is completely etched away is detected by optical emission spectroscopy (OES) to determine the etching endpoint of each cycle.

[0118] In some embodiments, the two base angles of the triangle of the vertical cross section of the grating structure 17 can vary in size respectively.

[0119] In some embodiments, the triangular prism mirror side wall of the grating structure 17 and the specific size (nanometer level) can selectively filter the wavelength of ultraviolet light and achieve selective angle transmission light intensity.

[0120] In some embodiments, the aspect ratio of the grating structure 17 is greater than 3:1 or greater than 5:1. However, it can not be limited thereto.

[0121] In some embodiments, the critical dimension of the grating groove between adjacent grating structures 17 is less than 50 nm. However, it can not be limited thereto.

[0122] In some embodiments, the surface roughness of the side wall of the grating structure 17 is 1 nm to 10 nm.

[0123] In some embodiments, the grating structure 17 includes a blazed grating.

[0124] In some embodiments, the optical glasses can be AI glasses.

[0125] Embodiments of the present application also provide an internal triangular grating structure of optical glasses, which is obtained by using the manufacturing method of the internal triangular grating structure of optical glasses provided by any one of the embodiments of the present application.

[0126] Reference Figure 8 In some embodiments, the triangular grating structure 17 (triangular grating structure) inside the optical glasses is arranged on the functional layer 10 and arranged in a periodic manner. The grating structure 17 has a triangular vertical cross section, and has a grating groove between adjacent grating structures 17. The grating structure 17 (grating groove) has a smooth side wall, and the surface roughness is 1 nm to 10 nm. The functional layer 10 is arranged on the substrate 100.

[0127] In some embodiments, the substrate 100 is a glass (SiO2) substrate. The functional layer 10 is a titanium dioxide (TiO2) layer.

[0128] In summary, the embodiment of the present application defines the mask topography of the triangular grating pattern by forming the triangular imprint glue pattern 12, and when forming the triangular grating structure 17 by etching the functional layer 10, the process of forming the first oxide layer, the second oxide layer 141, the side wall structure 14 and etching the functional layer 10 is repeatedly executed. Not only can the first mask pattern 111 be continuously consumed in the etching process, and the triangular topography thereof be continuously transferred to the functional layer 10 to form the grating structure 17 with the same triangular vertical section, thereby optimizing the patterning process of the triangular grating structure, but also the smooth side of the second mask pattern formed can be transferred to the two side walls of the grating structure 17 through pattern transfer, thereby achieving smooth processing of the side walls, and thus being applicable to enhancing optical performance, improving diffraction efficiency and long-term stability in use.

[0129] The above is only the preferred embodiment of the present application, and the embodiment is not used to limit the protection scope of the present application, so any equivalent changes made according to the content of the specification and drawings of the present application should also be included in the protection scope of the present application.

Claims

1. A method for manufacturing a triangular grating structure inside optical glasses, characterized in that, In order, they include: (a) Forming a non-metallic mask layer on the functional layer; (b) Forming multiple triangular imprinted adhesive patterns on the non-metallic mask layer; (c) The surface of the embossed pattern is subjected to a first process gas to remove burrs; (d) The non-metallic mask layer is etched and patterned using the imprinted adhesive pattern to form a plurality of triangular first mask patterns on the functional layer; (e) Using a second process gas, the surface of the first mask pattern is subjected to a second treatment to form a first oxide layer; (f) A second oxide layer is formed on the surface of the first mask pattern using an atomic layer deposition process; (g) The second oxide layer is etched back to form a smooth sidewall structure on both sides of the first mask pattern. The first mask pattern, the first oxide layer and the sidewall structure constitute a smooth second mask pattern. (h) The exposed surface of the functional layer is etched through the second mask pattern until the first oxide layer is completely etched away; Repeat steps (e) to (h) until the first mask pattern is completely etched and consumed, and form a plurality of triangular grating structures on the functional layer below the first mask pattern, and transfer the smooth lateral topography of the second mask pattern to the two sidewalls of the grating structures through pattern transfer.

2. The method for manufacturing the internal triangular grating structure of optical glasses according to claim 1, characterized in that, The functional layer is disposed on a substrate, the substrate including a glass substrate; and / or, the functional layer including a titanium dioxide layer; and / or, the non-metallic mask layer including a polycrystalline silicon layer; and / or, the first oxide layer including a silicon dioxide layer; and / or, the second oxide layer including a silicon dioxide layer.

3. The method for manufacturing the internal triangular grating structure of optical glasses according to claim 1, characterized in that, When executing (b), the specific steps include: A UV-curable imprinting adhesive is spin-coated onto the non-metallic mask layer; A transparent flexible template with a preset triangular grating pattern is pressed onto a non-metallic mask layer coated with the UV-curable imprinting adhesive. Under a pressure of 1 mTorr to 500 mTorr, the UV-curable imprinting adhesive is cured by ultraviolet irradiation, replicating the preset triangular grating pattern on the transparent flexible template onto the UV-curable imprinting adhesive. After demolding, an imprinting adhesive pattern with a triangular vertical cross-section is formed on the non-metallic mask layer; or... A thermosetting embossing adhesive is spin-coated onto the non-metallic mask layer; A hard template with a preset triangular grating pattern is pressed onto the non-metallic mask layer coated with the thermosetting imprinting adhesive. Under a pressure of 1 mTorr to 500 mTorr, the thermosetting imprinting adhesive is cured by heating, and the preset triangular grating pattern on the hard template is copied onto the thermosetting imprinting adhesive. After demolding, an imprinting adhesive pattern with a triangular vertical cross section is formed on the non-metallic mask layer.

4. The method for manufacturing the internal triangular grating structure of optical glasses according to claim 1, characterized in that, When executing (c), the first process gas includes O2, the temperature is 60℃~100℃, the pressure is 5mTorr~50mTorr, the source power is 500W~1000W, and the bias power is 0W~200W.

5. The method for manufacturing the internal triangular grating structure of optical glasses according to claim 4, characterized in that, The first treatment is performed by exciting O2 to form O2 plasma and filtering out charged particles in the O2 plasma to obtain O free radicals.

6. The method for manufacturing the internal triangular grating structure of optical glasses according to claim 1, characterized in that, When executing (e), the second process gas includes O2, and O2 plasma is formed by exciting O2, and charged particles in the O2 plasma are filtered out to obtain O free radicals for the second treatment. The temperature is 150°C to 200°C, the pressure is 500mTorr to 1Torr, the source power is 1000W to 2000W, and the bias power is turned off. Alternatively, the second process gas includes O2, and the second treatment is carried out by a thermal oxidation process at a temperature of 500℃~1000℃ for a time of 5s~60s.

7. The method for manufacturing the internal triangular grating structure of optical glasses according to claim 1, characterized in that, The non-metallic mask layer is etched and patterned using a dry etching process. The process gases include Cl2, HBr, SF6, and O2, and the dilution and dissociation gases include at least one of N2 and Ar. The temperature is -10℃ to 20℃, the pressure is 5mTorr to 100mTorr, the source power is 100W to 1000W, and the bias power is 5W to 100W.

8. The method for manufacturing the internal triangular grating structure of optical glasses according to claim 1, characterized in that, When performing the atomic layer deposition process, the temperature is 600℃~800℃, the pressure is 100mTorr~5000mTorr, the silicon source precursor includes SiH4 or tetraethyl orthosilicate, and the oxygen source includes at least one of N2O, O2, and O3; and / or, a dry etching process is used to etch back the second oxide layer, the process gas includes CF4, C4F8, NF3, and O2, the dilution and dissociation gas includes at least one of N2 and Ar, the temperature is 0℃~80℃, the pressure is 5mTorr~500mTorr, the source power is 500W~1000W, and the bias power is 50W~500W.

9. The method for manufacturing the internal triangular grating structure of optical glasses according to claim 1, characterized in that, The exposed surface of the functional layer is etched using a dry etching process. The process gases include Cl2, CH4, HBr, and O2, and the dilution and dissociation gases include at least one of N2, Ar, and He. The temperature is 0℃ to 60℃, the pressure is 1 mTorr to 1 Torr, the source power is 50W to 3000W, and the bias power is 50W to 200W.

10. A triangular grating structure inside optical glasses, characterized in that, It is obtained using the manufacturing method of the internal triangular grating structure of optical glasses as described in any one of claims 1-9.

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