Method for manufacturing special-shaped microlens and special-shaped microlens

Abstract

The invention discloses a method for manufacturing a special-shaped microlens and the special-shaped microlens, which can efficiently and stably repeat the processing of the special-shaped microlens, have fewer process flows, and compared with an ideal lens, the error introduced by the process is small.

Description

Technical Field

[0001] The invention belongs to the technical field of micro lens processing and manufacturing, and in particular relates to a method for manufacturing a special-shaped micro lens and the special-shaped micro lens. Background Art

[0002] Microlenses are commonly used optical devices, which are widely used in optical communications, infrared fields, consumer electronics, etc. Concave or convex microlenses are the main forms in optical devices. The lens needs to be packaged at the back or used with other devices in the optical path, which requires higher costs and increases processing time.

[0003] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0004] The object of the present invention is to provide a method for manufacturing a special-shaped microlens and a special-shaped microlens, which can efficiently and stably repeat the processing of the special-shaped microlens, have fewer process flows, and the error introduced by the process is small when the finished lens is compared with the ideal lens.

[0005] In order to achieve the above object, a specific embodiment of the present invention provides a method for manufacturing a special-shaped microlens, comprising:

[0006] Providing a first substrate, forming a first photoresist layer on a first surface of the first substrate, exposing and developing the first photoresist layer to form one or more columnar photoresist structures;

[0007] Heating the first substrate to allow each of the glue pillar structures to undergo thermal reflow to form a microlens surface shape;

[0008] Forming a protective layer on the surface of each of the microlens surfaces;

[0009] forming a second photoresist layer on the first surface of the first substrate, the second photoresist layer covering the microlens surface shape and the protective layer, exposing and developing the second photoresist layer to form one or more special-shaped structures exposing the microlens surface shape, the first substrate, the microlens surface shape and the special-shaped structures constituting a special-shaped microlens master mold;

[0010] forming an anti-sticking coating on the surface of the special-shaped microlens master mold;

[0011] forming a composite film layer on the special-shaped microlens master mold;

[0012] Demolding the composite film layer and the special-shaped microlens master mold;

[0013] Providing a second substrate, and forming an embossed adhesive layer on a first surface of the second substrate;

[0014] Aligning the first surface of the second substrate with the composite film layer, embossing, curing and demoulding, so as to form a special-shaped microlens surface on the embossed adhesive layer;

[0015] The surface shape of the irregular microlens is transferred to the second substrate by etching technology to form an irregular microlens.

[0016] In one or more embodiments of the present invention, the composite film layer includes a first film layer, a second film layer and a third film layer arranged in sequence, the first film layer is at least filled between the special-shaped structure and the microlens surface, the first film layer has a first hardness, the second film layer covers the special-shaped structure and the microlens surface, the second film layer has a second hardness greater than the first hardness, and the size of the third film layer is greater than the size of the second film layer.

[0017] In one or more embodiments of the present invention, the materials of the first photoresist layer and the second photoresist layer include positive photoresist and / or negative photoresist; and / or

[0018] The material of the protective layer includes solvent-free epoxy UV glue; and / or,

[0019] The material of the embossed adhesive layer includes polyacrylic acid UV-curable etching-resistant photoresist; and / or,

[0020] The first hardness is less than or equal to 40A; and / or,

[0021] The first hardness ranges from 25A to 40A; and / or,

[0022] The second hardness ranges from 45A to 50A; and / or,

[0023] The thickness of the composite film layer is in the range of 300 μm to 800 μm; and / or,

[0024] The materials of the first film layer and the second film layer both include PDMS and H-PDMS; and / or,

[0025] The third film layer is a PET film.

[0026] In one or more embodiments of the present invention, before the step of forming the embossed adhesive layer on the first surface of the second substrate, the step of coating a tackifier on the first surface of the second substrate is also included; and / or,

[0027] Forming an anti-sticking coating on the surface of the special-shaped microlens master mold comprises:

[0028] The surface of the special-shaped microlens master mold is treated with modified HMDS, and then coated and cured with hydroxy silicone oil to form an anti-sticking coating.

[0029] In one or more embodiments of the present invention, the profile of the irregular microlens is transferred to the second substrate by etching technology to form the irregular microlens, including:

[0030] The profile of the irregular microlens is transferred to the second substrate by dry etching technology, wherein after the profile of the microlens is completely transferred to the second substrate, the thickness of the embossed adhesive layer remaining on the surface of the irregular structure is greater than 1 μm;

[0031] The embossed adhesive layer on the surface of the special-shaped structure is removed to form a special-shaped microlens.

[0032] A specific embodiment of the present invention provides a method for manufacturing a special-shaped microlens, comprising:

[0033] Providing a first substrate, forming a first photoresist layer on a first surface of the first substrate, exposing and developing the first photoresist layer to form one or more columnar photoresist structures;

[0034] Heating the first substrate to allow each of the glue pillar structures to undergo thermal reflow to form a microlens surface shape;

[0035] Transferring the microlens surface shape to the first substrate by etching technology to form a microlens;

[0036] forming a second photoresist layer on the surface of the first substrate having the microlens, the second photoresist layer covering the microlens, exposing and developing the second photoresist layer to form one or more special-shaped structures exposing the microlens, the first substrate and the special-shaped structures constituting a special-shaped microlens master mold;

[0037] forming an anti-sticking coating on the surface of the special-shaped microlens master mold;

[0038] forming a composite film layer on the special-shaped microlens master mold;

[0039] Demolding the composite film layer and the special-shaped microlens master mold;

[0040] Providing a second substrate, and forming an embossed adhesive layer on a first surface of the second substrate;

[0041] Aligning the first surface of the second substrate with the composite film layer, embossing, curing and demoulding, so as to form a special-shaped microlens surface on the embossed adhesive layer;

[0042] The surface shape of the irregular microlens is transferred to the second substrate by etching technology to form an irregular microlens.

[0043] In one or more embodiments of the present invention, the composite film layer includes a second film layer and a third film layer arranged in sequence, the second film layer covers the special-shaped structure and the microlens surface, and the size of the third film layer is larger than that of the second film layer.

[0044] In one or more embodiments of the present invention, the materials of the first photoresist layer and the second photoresist layer include positive photoresist and / or negative photoresist; and / or,

[0045] The material of the embossed adhesive layer includes polyacrylic acid UV-curable etching-resistant photoresist; and / or,

[0046] The thickness of the composite film layer is in the range of 250 μm to 500 μm; and / or,

[0047] The material of the second film layer includes PDMS and H-PDMS; and / or,

[0048] The third film layer is a PET film; and / or,

[0049] The second film layer has a second hardness, and the second hardness ranges from 45A to 50A.

[0050] In one or more embodiments of the present invention, before the step of forming the embossed adhesive layer on the first surface of the second substrate, the step of coating a tackifier on the first surface of the second substrate is also included; and / or,

[0051] Forming an anti-sticking coating on the surface of the special-shaped microlens master mold comprises:

[0052] The surface of the special-shaped microlens master mold is treated with modified HMDS, and then coated and cured with hydroxy silicone oil to form an anti-sticking coating.

[0053] A specific embodiment of the present invention provides a special-shaped microlens, which is manufactured by the above-mentioned method for manufacturing the special-shaped microlens.

[0054] Compared with the prior art, the method for manufacturing the special-shaped microlens and the special-shaped microlens of the present invention can efficiently and stably repeat the processing of the special-shaped microlens, with fewer process flows, and the error introduced by the process is small when the finished lens is compared with the ideal lens.

[0055] The method for manufacturing the special-shaped microlens and the special-shaped microlens of the present invention have made a breakthrough in the nano-imprint processing capability of an integrated multi-structure lens, and the process is relatively simple and applicable to most substrate materials. The special-shaped microlens is quickly replicated by nano-imprint replication technology, which is extremely efficient and eliminates the multi-structure processing process. The semiconductor processing technology is used to accurately control the lens surface shape, and at the same time, the ability to ship polymer rubber balls can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0057] Figure 1 is a process flow chart of a method for manufacturing a special-shaped microlens in the first embodiment of the present invention;

[0058] Figure 2a-2j is a flowchart of the steps of the method for manufacturing a special-shaped microlens in the first embodiment of the present invention;

[0059] Figure 3 is a process flow chart of a method for manufacturing a special-shaped microlens in a second embodiment of the present invention;

[0060] Figure 4a-4j FIG. 4 is a flow chart of the steps of a method for manufacturing a special-shaped microlens in a second embodiment of the present invention. DETAILED DESCRIPTION

[0061] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0062] As mentioned in the background technology, microlenses are commonly used optical devices, which are widely used in optical communications, infrared fields, consumer electronics, etc. Concave or convex microlenses are the main forms in optical devices. The lens needs to be packaged at the back or used together with other devices in the optical path, which requires higher costs and increases processing time.

[0063] Based on this, the present application provides a method for manufacturing a special-shaped microlens and a special-shaped microlens, which can efficiently and stably repeat the processing of the special-shaped microlens, has fewer process flows, and the finished lens has a small error introduced by the process compared with the ideal lens.

[0064] The special-shaped microlens in the present application is essentially a special-shaped structure formed integrally around the microlens to surround, semi-surround, or partially surround the microlens. The shape of the special-shaped structure can be various, for example, it can be a groove formed around the microlens and having a square longitudinal section, or a groove formed around the microlens and having a triangular longitudinal section, etc. The specific shape of the special-shaped structure can be customized according to the needs of the output product, and this application does not limit it here.

[0065] like Figure 1 As shown, the method for manufacturing the special-shaped microlens in the first embodiment of the present invention specifically includes the following steps:

[0066] S1, providing a first substrate, forming a first photoresist layer on a first surface of the first substrate, exposing and developing the first photoresist layer to form one or more columnar photoresist structures.

[0067] S2, heating the first substrate to make each glue column structure reflow to form a microlens surface shape.

[0068] S3, forming a protective layer on the surface of each microlens.

[0069] S4, forming a second photoresist layer on the first surface of the first substrate, the second photoresist layer covering the microlens surface shape and the protective layer, exposing and developing the second photoresist layer to form one or more special-shaped structures exposing the microlens surface shape, the first substrate, the microlens surface shape and the special-shaped structures constitute a special-shaped microlens master mold.

[0070] S5, forming an anti-sticking coating on the surface of the special-shaped microlens mother mold.

[0071] S6, forming a composite film layer on the special-shaped microlens mother mold.

[0072] S7, demoulding the composite film layer and the special-shaped microlens mother mold.

[0073] S8, providing a second substrate, and forming an embossed adhesive layer on a first surface of the second substrate.

[0074] S9, aligning the first surface of the second substrate and the composite film layer, embossing, curing and demoulding, so as to form a special-shaped microlens surface on the embossed adhesive layer.

[0075] S10, transferring the surface shape of the irregular microlens to the second substrate through etching technology to form an irregular microlens.

[0076] The materials of the first photoresist layer and the second photoresist layer may include positive photoresist and / or negative photoresist. The material of the protective layer includes solvent-free epoxy UV glue, and the material of the embossing glue layer includes polyacrylic acid UV curing etch-resistant photoresist.

[0077] Thermal reflow of the first photoresist can not only form a microlens surface shape of the first photoresist, but also spontaneously form a smooth isolation layer on the surface of the microlens surface shape. The formation of the isolation layer can block the second photoresist applied subsequently, so that it will not be compatible with the first photoresist, and further the second photoresist will not affect the surface roughness of the microlens surface shape formed by the first photoresist. In order to further reduce the influence of the second photoresist, a protective layer is also formed on the surface of the microlens surface shape to completely block the second photoresist from being compatible with the first photoresist.

[0078] Step S5 specifically includes: performing a modified HMDS treatment on the surface of the special-shaped microlens master mold, and then coating and curing with hydroxy silicone oil to form an anti-sticking coating.

[0079] In step S6, the composite film layer may include different film layer structures according to the vertical angle difference of the sidewalls adjacent to the microlens surface on the special-shaped structure on the special-shaped microlens mother mold (affecting the size of the draft angle).

[0080] When the angle between the side wall adjacent to the microlens surface on the special-shaped structure on the special-shaped microlens master mold and the first surface of the first substrate is large, for example, the angle is greater than 85°, the composite film layer includes a first film layer, a second film layer and a third film layer arranged in sequence, the first film layer is at least filled between the special-shaped structure and the microlens surface, the first film layer has a first hardness, the second film layer covers the special-shaped structure and the microlens surface, the second film layer has a second hardness greater than the first hardness, and the size of the third film layer is greater than the size of the second film layer.

[0081] When the angle between the side wall of the irregular structure adjacent to the microlens surface on the irregular microlens master mold and the first surface of the first substrate is small, for example, the angle is less than 85°, the composite film layer only includes the second film layer and the third film layer which are arranged in sequence, the second film layer completely covers the irregular structure and the microlens surface, and the size of the third film layer is larger than that of the second film layer.

[0082] The materials of the first film layer and the second film layer both include PDMS (polydimethylsiloxane) and H-PDMS (hydrogen-terminated polydimethylsiloxane). The first hardness ranges less than or equal to 40A. Preferably, the first hardness ranges from 25A to 40A; the second hardness ranges from 45A to 50A; and the third film layer is a PET film. The thickness range of the composite film layer is 300μm to 800μm; the total thickness range of the first film layer and the second film layer is 200μm to 500μm, and the thickness range of the third film layer is 100μm to 300μm.

[0083] In step S8, before the step of forming the embossed adhesive layer on the first surface of the second substrate, the step of coating a tackifier on the first surface of the second substrate is also included.

[0084] In step S10, if the profiled structure has a top surface parallel to the first surface of the first substrate, in order to obtain a profiled structure with a flat top surface on the second substrate, in the process of transferring the profiled microlens surface to the second substrate by dry etching technology, first, after the microlens surface is completely transferred to the second substrate, the thickness of the embossed adhesive layer on the surface of the profiled structure is retained to be greater than 1 μm; then the embossed adhesive layer on the surface of the profiled structure is removed by a degumming liquid to form a profiled microlens. If the profiled structure does not have a top surface parallel to the first surface of the first substrate, the profiled microlens surface can be completely transferred to the second substrate by etching without degumming.

[0085] The following is combined with Figure 2a-2j , the method for manufacturing the irregular microlens in the first embodiment of the present application is described in detail. In this embodiment, the irregular microlens is specifically a microlens structure in a square groove.

[0086] refer to Figure 2a As shown, a first substrate 10 is provided. The first substrate 10 can be a metal, semiconductor, quartz, etc. with good mirror surface. Photoresist is applied twice on the first surface of the first substrate 10. The first time, AZ4620 photoresist is used to form one or more columnar glue column structures, and the glue column structure is made into a microlens surface shape 11 by heating and reflowing, and then 300nm thick SU-8 photoresist is sprayed for protection, and the UV energy is 100mj / cm 2 The protective layer 12 is formed by curing.

[0087] refer to Figure 2b As shown, AZ4620 photoresist is used to coat the first surface of the first substrate 10 multiple times, and the thickness of the photoresist is controlled to be 20 μm higher than the microlens surface 11, and a groove photoresist is used for photolithography. During photolithography, an MA8 photolithography machine is used for alignment photolithography, and the photolithography energy is 90 mj / cm 2 ~200mj / cm 2 After the photolithography is completed, 3038 developer is used for development at room temperature, and the AZ4620 photoresist at the bottom of the groove is visually observed. After the development is clean, it is washed and dried to complete the production of the special-shaped microlens master mold.

[0088] refer to Figure 2c As shown, at 70° C., the HMDS anti-sticking coating 20 is vacuum sprayed on the surface of the special-shaped microlens mother mold, and the water drop angle is controlled to 50 degrees after spraying to ensure smooth demoulding in the subsequent steps.

[0089] refer to Figure 2dAs shown, a composite film layer 30 is formed on the special-shaped microlens master mold. Specifically, 10g of the first component PDMS (molecular weight 20000) is weighed, and a Micro8 manual glue spreader is used, the speed is set to 3000r / min, and the rotation is performed for 8S. Then 4g of the second component H-PDMS (molecular weight 1000) is weighed, and a Micro8 manual glue spreader is used, the speed is set to 3000r / min, and the rotation is performed for 8S. The composite film layer 30 is coated on the surface of the special-shaped microlens master mold and filled between the groove structure and the microlens surface. The first film layer 31 with a hardness of 25A-40A can be obtained by curing at 80°C for 10 minutes. The first film layer 31 with a hardness between 25A-40A has better structural fidelity.

[0090] Then weigh 20g of the first component PDMS (molecular weight 100000), use a Micro8 manual glue machine, set the speed to 3000r / min, rotate for 30S, weigh 8g of the second component H-PDMS (molecular weight 1000), use a Micro8 manual glue machine, set the speed to 3000r / min, rotate for 8S, and apply it on the surface of the first film layer 31, completely covering the groove structure and the microlens surface. Curing at 80℃ for 10min can obtain a second film layer 32 with a hardness of 45A to 50A. The overall thickness of the first film layer 31 and the second film layer 32 can be controlled at 200μm-500μm. The second film layer 32 with a hardness of 45A-50A has a better life.

[0091] Weigh 2g of PDMS and 0.2g of H-PDMS and mix them evenly to form glue, use the glue to glue the third film layer 33-PET film and the cured second film layer 32 together, and cure at 60°C for 30min.

[0092] refer to Figure 2e As shown, the third film layer 33 bonded to the second film layer 32 and the first film layer 31 is manually separated from the special-shaped microlens mother mold to complete demoulding.

[0093] The demoulded composite film layer 30 is fixed to a soft film frame dedicated to the nanoimprinting equipment and fixed with screws.

[0094] refer to Figure 2f As shown, a second substrate 40 is provided. The second substrate 40 is a chalcogenide glass such as germanium, silicon, quartz, GaSe, etc., with a thickness of 500μm-1100μm. The first surface of the second substrate 40 is coated with a tackifier. On the first surface of the second substrate 40, a Micro8 manual glue spreader is used to set the speed to 1000r / min, rotate for 30S, and evenly spread the nanoimprint glue 50 on the first surface of the second substrate 40, with a thickness of about 30μm, and the pre-baking condition is 100℃, 3min.

[0095] refer to Figure 2g and Figure 2h As shown, the second substrate 40 coated with the embossing glue and the soft film frame equipped with the composite film layer 30 are installed on the nanoimprinting device, and the parameters are set to 0.01mm / s-5mm / s to evenly bring the composite film layer 30 into close contact with the glue-coated surface of the second substrate 40, and the UV curing energy is controlled to 400mj / 2 -40000mj / 2 After curing, the composite film layer 30 is separated from the second substrate 40 at a speed of 1 mm / s-10 mm / s to obtain a 1:1 replicated adhesive structure product - a special-shaped microlens surface.

[0096] refer to Figure 2i and Figure 2j As shown, the dry etching technology is used to transfer the irregular microlens surface to the second substrate 40. Dry etching technology, such as reactive ion beam etching (RIE) or inductively coupled plasma etching (ICP), is preferably an ICP technology with a higher etching speed. ICP etching gas can be but is not limited to C4F8 and SF6. Furthermore, the reactive etching gas flow rate and its type are 35sccm of SF6 and 30sccm of C4F8, the ICP power is 2000W, the HF power is 200W, and the pressure in the etching chamber is 10mtorr. During the debugging process, the gas composition or proportion can be changed according to actual needs. During the etching process, when the microlens surface is completely transferred to the second substrate 40, the thickness of the imprinted glue layer on the surface of the groove structure is still greater than 1μm; then the degumming liquid NMP or a glue machine is used to completely remove the imprinted glue layer on the surface of the groove structure to form an irregular microlens.

[0097] like Figure 3 As shown, the method for manufacturing the special-shaped microlens in the second embodiment of the present invention specifically includes the following steps:

[0098] S1, providing a first substrate, forming a first photoresist layer on a first surface of the first substrate, exposing and developing the first photoresist layer to form one or more columnar photoresist structures.

[0099] S2, heating the first substrate to make each glue column structure reflow to form a microlens surface shape.

[0100] S3, transferring the microlens surface shape to the first substrate through etching technology to form a microlens.

[0101] S4, forming a second photoresist layer on the surface of the first substrate with the microlens, the second photoresist layer covers the microlens, exposing and developing the second photoresist layer to form one or more special-shaped structures exposing the microlens, the first substrate and the special-shaped structures constitute a special-shaped microlens mother mold.

[0102] S5, forming an anti-sticking coating on the surface of the special-shaped microlens mother mold.

[0103] S6, forming a composite film layer on the special-shaped microlens mother mold.

[0104] S7, demoulding the composite film layer and the special-shaped microlens mother mold.

[0105] S8, providing a second substrate, and forming an embossed adhesive layer on a first surface of the second substrate.

[0106] S9, aligning the first surface of the second substrate and the composite film layer, embossing, curing and demoulding, so as to form a special-shaped microlens surface on the embossed adhesive layer.

[0107] S10, transferring the surface shape of the irregular microlens to the second substrate through etching technology to form an irregular microlens.

[0108] The materials of the first photoresist layer and the second photoresist layer may include positive photoresist and / or negative photoresist. The material of the imprinting adhesive layer includes polyacrylic acid UV curing etch-resistant photoresist.

[0109] Step S5 specifically includes: performing a modified HMDS treatment on the surface of the special-shaped microlens master mold, and then coating and curing with hydroxy silicone oil to form an anti-sticking coating.

[0110] In step S6, the composite film layer may include different film layer structures according to the vertical angle difference of the sidewalls adjacent to the microlens surface on the special-shaped structure on the special-shaped microlens mother mold (affecting the size of the draft angle).

[0111] When the angle between the side wall adjacent to the microlens surface on the special-shaped structure on the special-shaped microlens master mold and the first surface of the first substrate is large, for example, the angle is greater than 85°, the composite film layer includes a first film layer, a second film layer and a third film layer arranged in sequence, the first film layer is at least filled between the special-shaped structure and the microlens surface, the first film layer has a first hardness, the second film layer covers the special-shaped structure and the microlens surface, the second film layer has a second hardness greater than the first hardness, and the size of the third film layer is greater than the size of the second film layer.

[0112] When the angle between the side wall of the irregular structure adjacent to the microlens surface on the irregular microlens master mold and the first surface of the first substrate is small, for example, the angle is less than 85°, the composite film layer only includes the second film layer and the third film layer which are arranged in sequence, the second film layer completely covers the irregular structure and the microlens surface, and the size of the third film layer is larger than that of the second film layer.

[0113] Wherein, the materials of the first film layer and the second film layer both include PDMS (polydimethylsiloxane) and H-PDMS (hydrogen-terminated polydimethylsiloxane). The range of the first hardness is less than or equal to 40A. Preferably, the range of the first hardness is 25A-40A; the range of the second hardness is 45A-50A; and the third film layer is a PET film. The thickness range of the composite film layer is 300μm-800μm; the total thickness range of the first film layer and the second film layer is 200μm-500μm, the thickness range of the second film layer is 150μm-200μm, and the thickness range of the third film layer is 100μm-300μm.

[0114] In step S8, before the step of forming the embossed adhesive layer on the first surface of the second substrate, the step of coating a tackifier on the first surface of the second substrate is also included.

[0115] The following is combined with Figure 4a-4j , a method for manufacturing a special-shaped microlens in the second embodiment of the present application is described in detail. In this embodiment, the special-shaped microlens is a microlens structure with a triangular special-shaped structure having 45° inclined surfaces on both sides, such as Figure 4j shown.

[0116] refer to Figure 4a and Figure 4b As shown, a first substrate 10 is provided. The first substrate 10 can be a metal, semiconductor, quartz, etc. with good mirror surface. Photoresist is applied twice on the first surface of the first substrate 10 and an etching is performed. AZ4620 photoresist is used for the first time to form one or more columnar glue column structures, and the glue column structures are made into microlens surface shapes 11 by heating and reflowing. A dry etching device is used to etch the reflowed microlens surface shape 11 on the first substrate 10 to form a microlens, and the etching device can be an RIE or ICP etching device.

[0117] refer to Figure 4c As shown, AZ4620 photoresist is used to coat the surface of the first substrate 10 with microlenses for multiple times, and the thickness of the photoresist is controlled to be 20 μm higher than the microlenses. Grayscale photolithography equipment is used for photolithography. The grayscale photolithography equipment uses a PICOMast200 grayscale laser direct writing device to etch a special-shaped structure with 45° inclined surfaces on both sides around the microlenses. After the photolithography is completed, 3038 developer is used for room temperature development, and the AZ4620 photoresist at the bottom of the special-shaped structure is visually observed. After the development is clean, it is washed and dried to complete the production of the special-shaped microlens master mold.

[0118] refer to Figure 4d As shown, at 70° C., the HMDS anti-sticking coating 20 is vacuum sprayed on the surface of the special-shaped microlens mother mold, and the water drop angle is controlled to 50 degrees after spraying to ensure smooth demoulding in the subsequent steps.

[0119] refer to Figure 4e As shown, a composite film layer 30 is formed on the special-shaped microlens master mold. Specifically, 10g of two-component PDMS (molecular weight 20,000) is weighed and mixed with H-PDMS (molecular weight 1,000), and a Micro8 manual glue spreader is used to set the speed to 3,000 r / min, and the mixture is coated on the surface of the special-shaped microlens master mold to completely cover the special-shaped structure and microlens. Curing at 80°C for 10 minutes can obtain a second film layer 32 with a hardness of 45A to 50A, and the thickness of the second film layer 32 can be controlled at 150μm-200μm. The second film layer 32 with a hardness of 45A-50A has a better life.

[0120] Weigh 2g of PDMS and 0.2g of H-PDMS and mix them evenly to form glue, use the glue to glue the third film layer 33-PET film and the cured second film layer 32 together, and cure at 60°C for 30min.

[0121] refer to Figure 4f As shown, the third film layer 33 bonded to the second film layer 32 is manually separated from the special-shaped microlens mother mold to complete demoulding.

[0122] The demoulded composite film layer 30 is fixed to a soft film frame dedicated to the nanoimprinting equipment and fixed with screws.

[0123] refer to Figure 4g As shown, a second substrate 40 is provided. The second substrate 40 is a chalcogenide glass such as germanium, silicon, quartz, GaSe, etc., with a thickness of 500μm-1100μm. The first surface of the second substrate 40 is coated with a tackifier. On the first surface of the second substrate 40, a Micro8 manual glue spreader is used to set the speed to 2000r / min, rotate for 30S, and evenly apply the nanoimprint glue 50 on the first surface of the second substrate 40, with a thickness of about 30μm, and the pre-baking condition is 100℃, 3min.

[0124] refer to Figure 4h and Figure 4i As shown, the second substrate 40 coated with the embossing glue and the soft film frame equipped with the composite film layer 30 are installed on the nanoimprinting device, and the parameters are set to 0.01mm / s-5mm / s to evenly bring the composite film layer 30 into close contact with the glue-coated surface of the second substrate 40, and the UV curing energy is controlled to 400mj / 2 -40000mj / 2 After curing, the composite film layer 30 is separated from the second substrate 40 at a speed of 1 mm / s-10 mm / s to obtain a 1:1 replicated adhesive structure product - a special-shaped microlens surface.

[0125] refer to Figure 4jAs shown, the special-shaped microlens surface is transferred to the second substrate 40 by dry etching technology. Dry etching technology, such as reactive ion beam etching (RIE) or inductively coupled plasma etching (ICP), is preferably an ICP technology with a higher etching speed. ICP etching gas can be but is not limited to C4F8 and SF6. Further, the reactive etching gas flow rate and its type are 50sccm of SF6 and 30sccm of C4F8, the ICP power is 1800W, the HF power is 300W, and the pressure in the etching chamber is 10mtorr. During the debugging process, the gas composition or proportion can be changed according to actual needs.

[0126] The embodiments of the present application also provide a special-shaped microlens manufactured by using the two methods for manufacturing special-shaped microlenses mentioned above.

[0127] Compared with the prior art, the method for manufacturing the special-shaped microlens and the special-shaped microlens of the present invention can efficiently and stably repeat the processing of the special-shaped microlens, with fewer process flows, and the error introduced by the process is small when the finished lens is compared with the ideal lens.

[0128] The method for manufacturing the special-shaped microlens and the special-shaped microlens of the present invention have made a breakthrough in the nano-imprint processing capability of an integrated multi-structure lens, and the process is relatively simple and applicable to most substrate materials. The special-shaped microlens is quickly replicated by nano-imprint replication technology, which is extremely efficient and eliminates the multi-structure processing process. The semiconductor processing technology is used to accurately control the lens surface shape, and at the same time, the ability to ship polymer rubber balls can be achieved.

[0129] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0130] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for manufacturing a special-shaped microlens, characterized in that: include: Providing a first substrate, and forming a microlens surface pattern on a first surface of the first substrate through a first photoresist layer; Forming a protective layer on the surface of each of the microlens surfaces; One or more special-shaped structures exposing the microlens surface are formed on the first surface of the first substrate through a second photoresist layer, and the first substrate, the microlens surface and the special-shaped structures constitute a special-shaped microlens master mold; forming an anti-sticking coating on the surface of the special-shaped microlens master mold; forming a composite film layer on the special-shaped microlens master mold; Demolding the composite film layer and the special-shaped microlens master mold; Providing a second substrate, and forming an embossed adhesive layer on a first surface of the second substrate; Aligning the first surface of the second substrate with the composite film layer, embossing, curing and demoulding, so as to form a special-shaped microlens surface on the embossed adhesive layer; By means of etching technology, the surface shape of the irregular microlens is transferred to the second substrate to form an irregular microlens; Wherein, the protective layer is used to prevent the second photoresist from being compatible with the first photoresist; Forming a composite film layer on the special-shaped microlens master mold comprises: When the angle between the side wall of the special-shaped structure adjacent to the microlens surface shape and the first surface of the first substrate on the special-shaped microlens master mold is greater than 85°, the composite film layer includes a first film layer, a second film layer and a third film layer arranged in sequence, the first film layer is at least filled between the special-shaped structure and the microlens surface shape, the first film layer has a first hardness, the range of the first hardness is less than or equal to 40A, the second film layer covers the special-shaped structure and the microlens surface shape, the second film layer has a second hardness greater than the first hardness, and the size of the third film layer is greater than the size of the second film layer; When the angle between the side wall of the irregular structure adjacent to the microlens surface on the irregular microlens master mold and the first surface of the first substrate is less than 85°, the composite film layer only includes the second film layer and the third film layer which are arranged in sequence, the second film layer completely covers the irregular structure and the microlens surface, and the size of the third film layer is larger than that of the second film layer.

2. The method for manufacturing a special-shaped microlens according to claim 1, characterized in that: The materials of the first photoresist layer and the second photoresist layer include positive photoresist and / or negative photoresist; and / or The material of the protective layer includes solvent-free epoxy UV glue; and / or, The material of the embossed adhesive layer includes polyacrylic acid UV-curable etching-resistant photoresist; and / or, The first hardness ranges from 25A to 40A; and / or, The second hardness ranges from 45A to 50A; and / or, The thickness of the composite film layer is in the range of 300 μm to 800 μm; and / or, The materials of the first film layer and the second film layer both include PDMS and H-PDMS; and / or, The third film layer is a PET film.

3. The method for manufacturing a special-shaped microlens according to claim 1, characterized in that: Before the step of forming the embossed adhesive layer on the first surface of the second substrate, the step of coating a tackifier on the first surface of the second substrate is also included; and / or, Forming an anti-sticking coating on the surface of the special-shaped microlens master mold comprises: The surface of the special-shaped microlens master mold is treated with modified HMDS, and then coated and cured with hydroxy silicone oil to form an anti-sticking coating.

4. The method for manufacturing a special-shaped microlens according to claim 1, characterized in that: The special-shaped microlens is transferred to the second substrate by etching technology to form a special-shaped microlens, including: The profile of the irregular microlens is transferred to the second substrate by dry etching technology, wherein after the profile of the microlens is completely transferred to the second substrate, the thickness of the embossed adhesive layer remaining on the surface of the irregular structure is greater than 1 μm; The embossed adhesive layer on the surface of the special-shaped structure is removed to form a special-shaped microlens.

5. A method for manufacturing a special-shaped microlens, characterized in that: include: Providing a first substrate, and forming a microlens surface pattern on a first surface of the first substrate through a first photoresist layer; Transferring the microlens surface shape to the first substrate by etching technology to form a microlens; Forming one or more special-shaped structures exposing the microlenses on the surface of the first substrate having the microlenses through a second photoresist layer, wherein the first substrate and the special-shaped structures constitute a special-shaped microlens master mold; forming an anti-sticking coating on the surface of the special-shaped microlens master mold; forming a composite film layer on the special-shaped microlens master mold; Demolding the composite film layer and the special-shaped microlens master mold; Providing a second substrate, and forming an embossed adhesive layer on a first surface of the second substrate; Aligning the first surface of the second substrate with the composite film layer, embossing, curing and demoulding, so as to form a special-shaped microlens surface on the embossed adhesive layer; By means of etching technology, the surface shape of the irregular microlens is transferred to the second substrate to form an irregular microlens; Wherein, forming a composite film layer on the special-shaped microlens master mold comprises: When the angle between the side wall of the special-shaped structure adjacent to the microlens surface shape and the first surface of the first substrate on the special-shaped microlens master mold is greater than 85°, the composite film layer includes a first film layer, a second film layer and a third film layer arranged in sequence, the first film layer is at least filled between the special-shaped structure and the microlens surface shape, the first film layer has a first hardness, the range of the first hardness is less than or equal to 40A, the second film layer covers the special-shaped structure and the microlens surface shape, the second film layer has a second hardness greater than the first hardness, and the size of the third film layer is greater than the size of the second film layer; When the angle between the side wall of the irregular structure adjacent to the microlens surface on the irregular microlens master mold and the first surface of the first substrate is less than 85°, the composite film layer only includes the second film layer and the third film layer which are arranged in sequence, the second film layer completely covers the irregular structure and the microlens surface, and the size of the third film layer is larger than that of the second film layer.

6. The method for manufacturing a special-shaped microlens according to claim 5, characterized in that: The materials of the first photoresist layer and the second photoresist layer include positive photoresist and / or negative photoresist; and / or, The material of the embossed adhesive layer includes polyacrylic acid UV-curable etching-resistant photoresist; and / or, The thickness of the composite film layer is in the range of 250 μm to 500 μm; and / or, The material of the second film layer includes two-component PDMS and a second-component H-PDMS; and / or, The third film layer is a PET film; and / or, The second film layer has a second hardness, and the second hardness ranges from 45A to 50A.

7. The method for manufacturing a special-shaped microlens according to claim 5, characterized in that: Before the step of forming the embossed adhesive layer on the first surface of the second substrate, the step of coating a tackifier on the first surface of the second substrate is also included; and / or, Forming an anti-sticking coating on the surface of the special-shaped microlens master mold comprises: The surface of the special-shaped microlens master mold is treated with modified HMDS, and then coated and cured with hydroxy silicone oil to form an anti-sticking coating.

8. A special-shaped microlens, characterized in that: The special-shaped microlens is manufactured by the manufacturing method of any one of claims 1 to 4 or claims 5 to 7.

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