Patterning method for high-molecular polymer film

Abstract

The present invention provides a patterning method for a high-molecular polymer film, comprising: forming a hard mask material layer having a preset thickness h0 on a high-molecular polymer film layer; forming a photoresist layer having a preset shape on the hard mask material layer, wherein the photoresist layer has a coverage area and an exposed area; etching the hard mask material layer in the exposed area, and etching a first preset depth h1, wherein the first preset depth h1 is less than the preset thickness h0; removing the photoresist layer; performing blanket etching on the hard mask material layer, and etching a second preset depth h2; etching the exposed high-molecular polymer film layer; and removing the hard mask material layer to form a high-molecular polymer film layer having a preset shape. The second preset depth h2, the first preset depth h1 and the preset thickness h0 satisfy h2=h0-h1. The present invention solves the problem in the prior art of poor patterning quality of high-molecular polymer films.

Description

A method for patterning polymer films

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 7, 2023, with application number 202311676211.2 and invention name “Graphing method for polymer films”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the technical field of micro-nano processing equipment, and in particular to a method for patterning a high molecular polymer film. Background Art

[0003] Polymer films have a wide range of applications in optoelectronic devices, biomedical devices, and other fields. Among them, polymer waveguide devices are an important optoelectronic device with advantages such as low loss, low cost, and easy integration. Polymer waveguide devices typically consist of a sandwich structure of a cladding layer + polymer layer + cladding layer. The cladding layer and polymer layer can be made of materials such as PDMS (Polydimethylsiloxane) and PMMA (Polymethylmethacrylate). The polymer layer serves as the core layer and requires a patterning process to form the desired waveguide structure.

[0004] Currently, there are two main patterning processes for polymer waveguide devices: one using photoresist as an etch mask, and the other using a hard mask. While the process using photoresist as an etch mask is simpler, due to its inherent low etch selectivity and poor resolution, it struggles to meet the minimum feature size and edge precision requirements of polymer waveguide devices. Using a hard mask is more complex, but it can improve etch selectivity and resolution, enabling the fabrication of finer and smoother waveguide structures.

[0005] Currently, there are two commonly used methods for preparing hard masks: stripping and etching. In the stripping method, conventional organic stripping solutions are usually used to remove the hard mask material layer. However, polymer layers (such as PMMA) are easily soluble in conventional organic stripping solutions. When removing the hard mask material layer, the polymer layer is easily dissolved in the stripping solution, resulting in damage to the polymer layer.

[0006] The etching method involves preparing a hard mask material layer (such as a metal coating or oxide film layer) on the entire surface of a polymer film, then patterning the hard mask material layer using a photoresist, and etching it using a dry etching device (such as IBE (Ion Beam Etching), RIE (Reactive Ion Etching), or ICP (Inductive Coupled Plasma Emission Spectrometer)) to obtain a hard mask. The hard mask is then used as a mask to etch the polymer layer, and finally the hard mask is removed. The disadvantage of this method is that after the hard mask is patterned, the photoresist needs to be removed. If a wet method is used to remove the photoresist, conventional debonding solvents (such as acetone, ethanol, and NMP (N-Methylpyrrolidone)) will also damage the polymer layer. If the photoresist is removed by dry method, since the high molecular polymer (such as PMMA) itself can be used as a photoresist, when the photoresist on the hard mask is removed by dry method, the exposed high molecular polymer layer will be removed along with the photoresist or the surface will be damaged.

[0007] In summary, existing methods for patterning polymer films using hard masks as etch masks have certain drawbacks and deficiencies, making it difficult to ensure the patterning quality of the polymer core layer. Therefore, there is an urgent need to provide a new method for patterning polymer films using hard masks as etch masks to address the aforementioned issues.

[0008] Summary of the Invention

[0009] The main purpose of the present invention is to provide a method for patterning a polymer film to solve the problem of poor patterning quality of the polymer film in the prior art.

[0010] To achieve the above-mentioned purpose, according to one aspect of the present invention, a method for patterning a polymer film is provided, comprising: forming a hard mask material layer with a preset thickness h0 on the polymer film layer; forming a photoresist layer with a preset shape on the hard mask material layer, the photoresist layer having a covered area and an exposed area; etching the hard mask material layer in the exposed area to a first preset depth h1, wherein the first preset depth h1 is less than the preset thickness h0; removing the photoresist layer; etching the entire surface of the hard mask material layer to a second preset depth h2; etching the exposed polymer film layer; removing the hard mask material layer to form a polymer film layer with a preset shape; wherein the second preset depth h2, the first preset depth h1 and the preset thickness h0 satisfy h2=h0-h1.

[0011] Furthermore, before forming the hard mask material layer with a preset thickness h0 on the high molecular polymer film layer, the process further includes: forming a first cladding layer on the substrate layer; and forming the high molecular polymer film layer on the first cladding layer.

[0012] Furthermore, in the process of forming the first cladding layer on the substrate layer, the first cladding layer is formed by coating.

[0013] Furthermore, in the process of forming the high molecular polymer film layer on the first coating layer, the high molecular polymer film layer is formed by coating.

[0014] Furthermore, after the hard mask material layer is removed to form the high molecular polymer film layer having a preset shape, the process further includes: forming a second coating layer on the high molecular polymer film layer.

[0015] Furthermore, the materials of the first coating layer, the second coating layer and the high molecular polymer film layer include at least one of acrylic resin, polydimethylsiloxane and polyimide.

[0016] Furthermore, in the process of forming the second coating layer on the high molecular polymer film layer, the second coating layer is formed by coating.

[0017] Furthermore, in the process of forming the hard mask material layer with a preset thickness h0 on the high molecular polymer film layer, the hard mask material layer is formed by magnetron sputtering or thermal evaporation.

[0018] Furthermore, the hard mask material layer is etched twice or more.

[0019] Furthermore, in the process of etching the hard mask material layer in the exposed area and etching to a first preset depth h1, wherein the first preset depth h1 is less than the preset thickness h0, the hard mask material layer in the exposed area is etched at least once, wherein when the hard mask material layer in the exposed area is etched multiple times, the first preset depth h1 is etched cumulatively multiple times; and / or in the process of etching the entire surface of the hard mask material layer and etching to a second preset depth h2, the entire surface of the hard mask material layer is etched at least once, wherein when the entire surface of the hard mask material layer is etched multiple times, the second preset depth h2 is etched cumulatively multiple times.

[0020] Furthermore, the hard mask material layer includes at least one of a metal plating layer and an oxide film layer.

[0021] Applying the technical solution of the present invention, a method for patterning a polymer film includes: forming a hard mask material layer with a preset thickness h0 on the polymer film layer; forming a photoresist layer with a preset shape on the hard mask material layer, the photoresist layer having a covered area and an exposed area; etching the hard mask material layer in the exposed area to a first preset depth h1, the first preset depth h1 being less than the preset thickness h0; removing the photoresist layer; etching the entire surface of the hard mask material layer to a second preset depth h2; etching the exposed polymer film layer; removing the hard mask material layer to form a polymer film layer with a preset shape; wherein the second preset depth h2, the first preset depth h1, and the preset thickness h0 satisfy h2=h0-h1.

[0022] By forming a photoresist layer of a preset shape on the hard mask material layer, a portion of the hard mask material layer is covered by the photoresist layer, while another portion of the hard mask material layer is exposed externally, facilitating subsequent etching of the hard mask material layer within the exposed area. When etching the hard mask material layer within the exposed area, the etching depth of the hard mask material layer is less than the thickness of the hard mask material layer, leaving some hard mask material to protect the polymer film layer. Because some hard mask material remains in the exposed area, the polymer film layer is not damaged during removal of the photoresist layer, which is beneficial to the integrity of the polymer film layer. Because the hard mask material layer within the exposed area has a height difference from the hard mask material layer within the covered area, after removing the photoresist layer, the hard mask material layer within the exposed area can be accurately removed to form a mask plate with a preset shape, and then the polymer film layer can be etched. Since no damage is caused to the polymer film layer before etching, the quality of the patterning of the polymer film layer is effectively improved, which is conducive to the preparation of finer and smoother waveguide structures and meets the requirements of polymer waveguide devices for minimum feature size and edge accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG1 shows a schematic flow chart of a method for patterning a polymer film according to an optional embodiment of the present invention.

[0024] The above drawings include the following reference numerals: 10, polymer film layer; 20, hard mask material layer; 30, photoresist layer; 40, cover area; 50, exposed area; 60, substrate layer; 70, first cladding layer. DETAILED DESCRIPTION

[0025] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0026] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0027] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity direction; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above directional words are not used to limit the present invention.

[0028] In order to solve the problem of poor patterning quality of high molecular polymer films in the prior art, the present invention provides a method for patterning high molecular polymer films.

[0029] As shown in Figure 1, the patterning method of a polymer film includes: forming a hard mask material layer 20 with a preset thickness h0 on the polymer film layer 10; forming a photoresist layer 30 with a preset shape on the hard mask material layer 20, the photoresist layer 30 having a covered area 40 and an exposed area 50; etching the hard mask material layer 20 in the exposed area 50 and etching to a first preset depth h1, the first preset depth h1 being less than the preset thickness h0; removing the photoresist layer 30; etching the entire surface of the hard mask material layer 20 and etching to a second preset depth h2; etching the exposed polymer film layer 10; removing the hard mask material layer 20 to form a polymer film layer 10 with a preset shape; wherein the second preset depth h2, the first preset depth h1 and the preset thickness h0 satisfy h2=h0-h1.

[0030] By forming a photoresist layer 30 of a predetermined shape on the hard mask material layer 20, a portion of the hard mask material layer 20 is covered by the photoresist layer 30, while another portion of the hard mask material layer 20 is exposed. This facilitates subsequent etching of the hard mask material layer 20 within the exposed region 50. When etching the hard mask material layer 20 within the exposed region 50, the etching depth of the hard mask material layer 20 is less than the thickness of the hard mask material layer 20, leaving some hard mask material to protect the polymer film layer 10. Because some hard mask material remains in the exposed region 50, the polymer film layer 10 is not damaged during removal of the photoresist layer 30, thereby maintaining the integrity of the polymer film layer 10. Because the hard mask material layer 20 in the exposed area 50 has a height difference from the hard mask material layer 20 in the covered area 40, the hard mask material layer 20 in the exposed area 50 can be accurately removed after removing the photoresist layer 30 to form a mask with a predetermined shape, and then the polymer film layer 10 can be etched. Because the polymer film layer 10 is not damaged before etching, the patterning quality of the polymer film layer 10 is effectively improved, facilitating the fabrication of finer and smoother waveguide structures and meeting the minimum feature size and edge precision requirements of polymer waveguide devices.

[0031] Since the material of the photoresist layer 30 is softer than that of the hard mask material layer 20 and is easier to remove than the hard mask material layer 20, the removal of the photoresist layer 30 has less impact on the hard mask material layer 20, making the hard mask material layer 20 more accurate during imaging, thereby improving the quality of the patterning of the polymer film layer 10.

[0032] In the prior art, the etching time for the hard mask material layer 20 is long, which increases the time the photoresist layer 30 spends in the etching equipment, thereby causing the photoresist layer 30 to carbonize or deform. The carbonized or denatured photoresist layer 30 is extremely difficult to remove whether using a wet method or a dry method. In the present application, the step of removing the photoresist layer 30 is performed after the hard mask material layer 20 is first etched and the first preset depth h1 is etched. The time the photoresist layer 30 spends in the etching equipment is shortened, and the risk of carbonization or deformation of the photoresist layer 30 is reduced, so that the time to remove the photoresist layer 30 is shortened. It should be noted that dry etching equipment can be used in the process of etching the exposed high molecular polymer film layer 10.

[0033] In the process of removing the hard mask material layer 20 to form the high molecular polymer film layer 10 having a preset shape, a dry etching device may be used to remove the remaining hard mask material layer 20 .

[0034] Specifically, before forming the hard mask material layer 20 having a predetermined thickness h0 on the polymer film layer 10, the process further includes: forming a first coating layer 70 on the substrate layer 60; and forming the polymer film layer 10 on the first coating layer 70. The first coating layer 70 protects the polymer film layer 10, thereby reducing stretching and damage to the polymer film layer 10.

[0035] It should be noted that the first cladding layer 70 and the polymer film layer 10 may be an integrally formed structure. Specifically, the first cladding layer 70 and the polymer film layer 10 may be formed simultaneously on the substrate layer 60 .

[0036] Optionally, during the process of forming the first cladding layer 70 on the substrate layer 60 , the first cladding layer 70 is formed by coating. The coating method is conducive to forming a uniform first cladding layer 70 .

[0037] Optionally, the first coating layer 70 may be coated by spin coating, roller coating, or the like. Of course, other methods may also be used to form the first coating layer 70, which is not specifically limited here.

[0038] Specifically, in the process of forming the polymer thin film layer 10 on the first coating layer 70 , the polymer thin film layer 10 is formed by coating. The coating method is conducive to forming a uniform polymer thin film layer 10 .

[0039] Optionally, the polymer film layer 10 may be coated by spin coating, roller coating, or the like. Of course, other methods may also be used to form the polymer film layer 10, which are not specifically limited herein.

[0040] Optionally, after removing the hard mask material layer 20 using a dry etching device to form the polymer film layer 10 having a preset shape, the process further includes forming a second coating layer on the polymer film layer 10. After forming the polymer film layer 10 having the preset shape, the second coating layer is formed on the polymer film layer 10, thereby forming a sandwich structure of coating layer + polymer film layer 10 + coating layer. The sandwich structure protects the polymer film layer 10 on both sides, further improving the protection of the polymer film layer 10.

[0041] Optionally, the material of the first coating layer 70, the second coating layer, and the polymer film layer 10 includes at least one of acrylic resin, polydimethylsiloxane, and polyimide. The materials of the first coating layer 70, the second coating layer, and the polymer film layer 10 can be selected based on the actual use requirements of the polymer film. Of course, the materials of the first coating layer 70, the second coating layer, and the polymer film layer 10 can be the same or different, and are not specifically limited here.

[0042] It should be noted that when the first coating layer 70 and the polymer film layer 10 are made of the same material, the first coating layer 70 and the polymer film layer 10 can be prepared in the same process. Of course, the first coating layer 70 and the polymer film layer 10 can also be formed in steps, and no specific restrictions are made here.

[0043] Optionally, the first coating layer 70 and the polymer film layer 10 may be an integral structure. When the first coating layer 70 and the polymer film layer 10 are an integral structure, the two may be collectively referred to as the polymer film layer 10. In this case, when patterning the polymer film layer 10, it is not necessary to completely etch the exposed polymer film layer 10.

[0044] The present application is not limited to any material of the polymer film layer 10 . Regardless of whether the polymer film layer 10 is soluble in an organic or inorganic solvent, the method of the present application can be used for patterning.

[0045] Specifically, in the process of forming the second coating layer on the polymer film layer 10, the second coating layer is formed by coating, which is conducive to forming a uniform second coating layer.

[0046] Optionally, the second coating layer can be coated by spin coating, roller coating, etc. Of course, other methods can also be used to form the second coating layer, which is not specifically limited here.

[0047] Optionally, during the process of forming the hard mask material layer 20 having a preset thickness h0 on the polymer film layer 10, the hard mask material layer 20 is formed by magnetron sputtering or thermal evaporation. During the process of forming the hard mask material layer 20, the process for preparing the hard mask material layer 20 can be selected based on the material of the hard mask material layer 20 and the material of the polymer film layer 10, and is not specifically limited herein.

[0048] In the method for patterning a polymer film described herein, the etching step can be performed using either dry or wet etching equipment, and the choice is not limited to a specific method. Dry etching is more advantageous for process control, allows for more precise control of patterns with small feature sizes, and is more conducive to improving pattern accuracy.

[0049] Conventional gases, such as argon and fluorine-based gases, can be used for dry etching in this application. Toxic gases such as chlorine-based gases do not need to be used during the etching process, which is safer and more environmentally friendly.

[0050] In the process of the present invention, no organic solvent other than the developer is used, and the polymer film layer 10 will not be damaged during the process.

[0051] When dry etching equipment is used in the etching step of the polymer film patterning method of the present application, conventional alkali is not used, and the corresponding cationic metal is not introduced during the process, which is more conducive to process control. This makes the polymer film patterning method of the present application not limited by feature size, and the patterning accuracy of the polymer film layer 10 with large and small feature sizes can be guaranteed. In addition, this configuration means that no organic solvents other than the developer are used in the polymer film patterning method of the present application, and the polymer film layer 10 will not be damaged before etching.

[0052] When using dry etching equipment for etching, at least one of IBE equipment (Ion Beam Etching, ion beam etching equipment), RIE equipment (Reactive Ion Etching, reactive ion etching equipment), and ICP equipment (Inductive Coupled Plasma Emission Spectrometer, inductively coupled plasma equipment) can be used. The dry etching equipment can be selected according to specific usage requirements.

[0053] The present invention utilizes the high etching selectivity and high resolution of IBE and RIE equipment to produce finer and smoother waveguide structures, meeting the minimum feature size and edge precision requirements of polymer waveguide devices. It also reduces damage to the polymer core layer caused by organic solvents or acid-base solutions, ensuring the integrity and patterning quality of the polymer film layer 10.

[0054] Of course, wet process can also be used in some etching steps. There is no specific limitation here. Dry etching is preferably used. Compared with wet etching, dry etching is more conducive to process control and can more accurately control graphics with small feature sizes.

[0055] Optionally, the hard mask material layer 20 is etched two or more times. That is, the total number of etchings for the hard mask material layer 20 can be two or more times, and can be designed based on the pattern to be etched on the polymer film layer 10, without specific limitation herein. For example, the total number of etchings for the hard mask material layer 20 can be three times, four times, etc., without specific limitation herein.

[0056] Specifically, during the etching of the hard mask material layer 20 in the exposed region 50 to a first predetermined depth h1, where the first predetermined depth h1 is less than the predetermined thickness h0, the hard mask material layer 20 in the exposed region 50 is etched at least once. When the hard mask material layer 20 in the exposed region 50 is etched multiple times, the first predetermined depth h1 is accumulated during the multiple etchings. In other words, the etching of the first predetermined depth h1 may be performed multiple times, and the accumulated depth of the multiple etchings is h1.

[0057] Alternatively, during the entire surface etching of the hard mask material layer 20 and the etching to the second preset depth h2, the entire surface etching of the hard mask material layer 20 may be performed at least once. When the entire surface etching of the hard mask material layer 20 is performed multiple times, the second preset depth h2 is accumulated over the multiple etchings. In other words, the second preset depth h2 may be etched multiple times, and the accumulated depth of the multiple etchings is h2.

[0058] Optionally, the hard mask material layer 20 includes at least one of a metal plating layer and an oxide thin film layer. The hard mask material layer 20 may be a single metal plating layer, multiple metal plating layers, a single oxide thin film layer, multiple oxide thin film layers, or a combination of metal plating layers and oxide thin film layers, for example, a combination of alternating metal plating layers and oxide thin film layers.

[0059] The oxide film layer can be a metal oxide film layer or a non-metal oxide film layer, and there is no specific limitation here. It only needs to ensure that the structure of the hard mask material layer 20 has a relatively high strength.

[0060] Optionally, the material of the hard mask material layer 20 may include at least one of aluminum, copper, gold, silver, platinum, titanium, chromium, nickel, tantalum, tungsten, titanium nitride, titanium tungsten alloy, nickel titanium alloy, tantalum nitride, aluminum oxide, silicon dioxide, silicon nitride, silicon oxynitride, and phosphorus-doped silicate glass.

[0061] Optionally, a dry stripping device is used to remove the photoresist layer 30 during the removal process. Since the dry stripping device does not remove the hard mask material layer 20 when removing the photoresist layer 30, the pattern integrity of the hard mask material layer 20 is ensured, which is conducive to higher precision and higher quality of patterning of the polymer film layer 10.

[0062] Of course, other equipment can be used to remove the photoresist layer 30, such as IBE equipment, RIE equipment, ICP equipment, etc. There is no specific restriction here. It only needs to ensure that the polymer film layer 10 is not damaged when the photoresist layer 30 is removed.

[0063] Specifically, in the process of forming the photoresist layer 30 having a preset shape on the hard mask material layer 20, a photoresist material is coated on the hard mask material layer 20 to form a subbing layer; a projection lithography machine is used to project the preset shape onto the subbing layer and expose the subbing layer; and a developer is used to develop the subbing layer to form the photoresist layer 30 having the preset shape. The area washed away by the developer is the exposed area 50, and the area not washed away by the developer is the covered area 40. The photoresist material used in this application can be any commercially available photoresist that meets the required resolution, which reduces restrictions on the photoresist material and helps reduce costs.

[0064] The process flow of the present invention is simple, reliable and easy to control, and is suitable for batch production of high molecular polymer waveguide devices, thereby reducing production costs and improving production efficiency.

[0065] Example 1

[0066] Step 1: Spin-coat 10 μm thick PDMS (polydimethylsiloxane) on the substrate to form a first coating layer 70;

[0067] Step 2: Spin-coat 1 μm thick PMMA (polymethyl methacrylate) on the first coating layer 70 to form a high molecular polymer film layer 10;

[0068] Step 3: Use magnetron sputtering to grow a 10 nm Cr layer and a 120 nm Au layer to form a hard mask material layer 20;

[0069] Step 4: spin-coating 800nm ​​AR80 photoresist to form a subbing layer, using a projection lithography machine to project a preset shape onto the subbing layer to expose the subbing layer, and using 3038 solution to develop the subbing layer to form a photoresist layer 30 having the preset shape;

[0070] Step 5: Using the photoresist layer 30 as a mask, an IBE device is used to etch the hard mask material layer 20 in the exposed area 50 to a depth of 70 nm.

[0071] Step six: using oxygen plasma equipment to remove the photoresist layer 30 .

[0072] Step seven: continue etching the hard mask material layer 20 using IBE until the remaining 60 nm thick hard mask material layer 20 in the exposed area 50 is completely etched away, thereby forming a hard mask material layer 20 with a preset shape.

[0073] Step eight: using the hard mask material layer 20 with a preset shape as a mask, select RIE equipment to etch the polymer thin film layer 10 with an etching depth of 1 μm to form a polymer thin film layer 10 with a preset shape.

[0074] Step nine: spin-coat 10 μm of PDMS on the high molecular polymer film layer 10 having a preset shape to form a second coating layer.

[0075] Example 2

[0076] The difference from the first embodiment is that the graphical method uses different equipment and parameters.

[0077] Step 1: Spin-coat 10 μm thick PDMS (polydimethylsiloxane) on the substrate to form a first coating layer 70;

[0078] Step 2: Spin-coat 1 μm thick PMMA (polymethyl methacrylate) on the first coating layer 70 to form a high molecular polymer film layer 10;

[0079] Step 3: using magnetron sputtering to grow a 10 nm Cr layer and a 100 nm Au layer to form a hard mask material layer 20;

[0080] Step 4: Spin-coat 800nm ​​SPR955 photoresist to form a subbing layer, use a projection lithography machine to project a preset shape onto the subbing layer to expose the subbing layer, and use 3038 solution to develop the subbing layer to form a photoresist layer 30 with the preset shape;

[0081] Step 5: Using the photoresist layer 30 as a mask, an IBE device is used to etch the hard mask material layer 20 in the exposed area 50 to a depth of 60 nm.

[0082] Step six: using oxygen plasma equipment to remove the photoresist layer 30 .

[0083] Step seven: continue etching the hard mask material layer 20 using IBE until the remaining 50 nm thick hard mask material layer 20 in the exposed area 50 is completely etched away, thereby forming a hard mask material layer 20 with a preset shape.

[0084] Step eight: using the hard mask material layer 20 with a preset shape as a mask, an ICP device is selected to etch the polymer thin film layer 10 with an etching depth of 1 μm to form a polymer thin film layer 10 with a preset shape.

[0085] Step nine: spin-coat 10 μm of PDMS on the high molecular polymer film layer 10 having a preset shape to form a second coating layer.

[0086] Example 3

[0087] The difference from the first embodiment is that the graphical method uses different equipment and parameters.

[0088] Step 1: growing 100 nm of Al (aluminum) on the substrate to form a first cladding layer 70;

[0089] Step 2: Spin-coat 1 μm thick PMMA (polymethyl methacrylate) on the first coating layer 70 to form a high molecular polymer film layer 10;

[0090] Step 3: using magnetron sputtering to grow a 10 nm Cr layer and a 100 nm Au layer to form a hard mask material layer 20;

[0091] Step 4: Spin-coat 800nm ​​SPR955 photoresist to form a subbing layer, use a projection lithography machine to project a preset shape onto the subbing layer to expose the subbing layer, and use 3038 solution to develop the subbing layer to form a photoresist layer 30 with the preset shape;

[0092] Step 5: Using the photoresist layer 30 as a mask, an IBE device is used to etch the hard mask material layer 20 in the exposed area 50 to a depth of 60 nm.

[0093] Step six: using oxygen plasma equipment to remove the photoresist layer 30 .

[0094] Step seven: continue etching the hard mask material layer 20 using IBE until the remaining 50 nm thick hard mask material layer 20 in the exposed area 50 is completely etched away, thereby forming a hard mask material layer 20 with a preset shape.

[0095] Step eight: using the hard mask material layer 20 with a preset shape as a mask, an ICP device is selected to etch the polymer thin film layer 10 with an etching depth of 1 μm to form a polymer thin film layer 10 with a preset shape.

[0096] Step nine: spin-coat 10 μm of PDMS on the high molecular polymer film layer 10 having a preset shape to form a second coating layer.

[0097] Obviously, the embodiments described above 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 making creative efforts should fall within the scope of protection of the present invention.

[0098] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, tasks, devices, components and / or combinations thereof.

[0099] It should be noted that the terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0100] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A method for patterning a polymer film, characterized in that: include: Forming a hard mask material layer (20) with a preset thickness h0 on the high molecular polymer film layer (10); Forming a photoresist layer (30) having a preset shape on the hard mask material layer (20), wherein the photoresist layer (30) has a covered area (40) and an exposed area (50); Etching the hard mask material layer (20) in the exposed area (50) to a first preset depth h1, wherein the first preset depth h1 is less than the preset thickness h0; removing the photoresist layer (30); Performing full-surface etching on the hard mask material layer (20), and etching to a second preset depth h2; Etching the exposed high molecular polymer film layer (10); Removing the hard mask material layer (20) to form a high molecular polymer film layer (10) having the preset shape; The second preset depth h2, the first preset depth h1 and the preset thickness h0 satisfy h2=h0-h1.

2. The method for patterning a polymer film according to claim 1, characterized in that: Before the process of forming a hard mask material layer (20) with a preset thickness h0 on the high molecular polymer film layer (10), the process further includes: forming a first cladding layer (70) on the substrate layer (60); The high molecular polymer film layer (10) is formed on the first coating layer (70).

3. The method for patterning a polymer film according to claim 2, characterized in that: In the process of forming the first cladding layer (70) on the substrate layer (60), the first cladding layer (70) is formed by coating.

4. The method for patterning a polymer film according to claim 2, characterized in that: In the process of forming the high molecular polymer film layer (10) on the first coating layer (70), the high molecular polymer film layer (10) is formed by coating.

5. The method for patterning a polymer film according to claim 2, characterized in that: After the process of removing the hard mask material layer (20) to form the high molecular polymer film layer (10) having the preset shape, the process further includes: A second coating layer is formed on the high molecular polymer film layer (10).

6. The method for patterning a polymer film according to claim 5, characterized in that: The materials of the first coating layer (70), the second coating layer, and the high molecular polymer film layer (10) include at least one of acrylic resin, polydimethylsiloxane, and polyimide.

7. The method for patterning a polymer film according to claim 5, characterized in that: In the process of forming the second coating layer on the high molecular polymer film layer (10), the second coating layer is formed by coating.

8. The method for patterning a polymer film according to any one of claims 1 to 7, characterized in that: In the process of forming a hard mask material layer (20) with a preset thickness h0 on a high molecular polymer film layer (10), a magnetron sputtering method or a thermal evaporation method is used to form the hard mask material layer (20).

9. The method for patterning a polymer film according to any one of claims 1 to 7, characterized in that: The hard mask material layer (20) is etched more than or equal to twice.

10. The method for patterning a polymer film according to any one of claims 1 to 7, characterized in that: In the process of etching the hard mask material layer (20) in the exposed area (50) and etching to a first preset depth h1, wherein the first preset depth h1 is less than the preset thickness h0, the hard mask material layer (20) in the exposed area (50) is etched at least once, wherein when the hard mask material layer (20) in the exposed area (50) is etched multiple times, the first preset depth h1 is etched cumulatively multiple times; and / or In the process of etching the entire surface of the hard mask material layer (20) and etching to the second preset depth h2, the hard mask material layer (20) is etched entirely at least once, wherein when the hard mask material layer (20) is etched entirely multiple times, the second preset depth h2 is etched cumulatively multiple times.

11. The method for patterning a polymer film according to any one of claims 1 to 7, characterized in that: The hard mask material layer (20) comprises at least one of a metal plating layer and an oxide film layer.

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