阅读说明：本技术 一种提高模板转印柔性衬底微结构位置精度的方法 (Method for improving position precision of template transfer printing flexible substrate microstructure ) 是由 高国涵 范斌 李志炜 刘鑫 于 2019-09-11 设计创作，主要内容包括：本发明提供了一种提高模板转印柔性衬底微结构位置精度的方法,先将微孔陶瓷吸附板贴于微结构柔性衬底表面,抽真空使微结构柔性衬底上表面被牢牢吸附于微孔陶瓷吸附板表面,然后通过物理或化学手段使微结构柔性衬底下表面与微结构刚性模板分离,再利用胶粘剂将刚性支撑边框与微结构柔性衬底粘接固定,最后释放吸附板的真空,实现微结构柔性衬底从微结构刚性模板到刚性支撑边框的高精度转移。本发明可以实现真正意义上的柔性衬底薄膜透镜,摆脱了传统刚性基底的束缚,利于光学元件的轻量化。本发明可以克服先剥离薄膜再固定薄膜造成的面内不可逆变形,最大程度地保持了微结构位置的精度,有利于光学波前的无损保留。(The invention provides a method for improving the position precision of a microstructure of a template transfer printing flexible substrate, which comprises the steps of firstly attaching a microporous ceramic adsorption plate to the surface of a microstructure flexible substrate, vacuumizing to enable the upper surface of the microstructure flexible substrate to be firmly adsorbed to the surface of the microporous ceramic adsorption plate, then separating the lower surface of the microstructure flexible substrate from a microstructure rigid template through a physical or chemical means, then adhering and fixing a rigid support frame and the microstructure flexible substrate by using an adhesive, and finally releasing the vacuum of the adsorption plate to realize the high-precision transfer of the microstructure flexible substrate from the microstructure rigid template to the rigid support frame. The invention can realize the flexible substrate film lens in the true sense, gets rid of the constraint of the traditional rigid base and is beneficial to the light weight of the optical element. The invention can overcome the in-plane irreversible deformation caused by peeling the film firstly and then fixing the film, furthest maintains the precision of the microstructure position and is beneficial to the lossless retention of the optical wavefront.)

1. The method for improving the position accuracy of the template transfer printing flexible substrate microstructure is characterized in that the device utilized by the method comprises a microporous ceramic adsorption plate (1), an adsorption plate base (2), an air pressure adjusting pipeline (3), a microstructure flexible substrate (4), a microstructure rigid template (5), a rigid supporting frame (6) and an adhesive (7); the mutual relation is that the microporous ceramic adsorption plate (1), the adsorption plate base (2) and the air pressure adjusting pipeline (3) are integrated into a whole and have an adsorption function, the microstructure flexible substrate (4) and the microstructure rigid template (5) are integrated into a whole, the binding force between the microstructure flexible substrate and the microstructure rigid template is large, and the surface of the rigid support frame (6) is coated with an adhesive (7) and is bonded with the microstructure flexible substrate (4); the method comprises the working procedures of firstly transferring a microstructure flexible substrate (4) to a microporous ceramic adsorption plate (1) from a microstructure rigid template (5) by using a vacuum adsorption mode, then transferring the microstructure flexible substrate (4) to a rigid support frame (6) from the microporous ceramic adsorption plate (1) by using an adhesive (7), and finally removing the vacuum to finish the transfer.

2. The method for improving the position accuracy of the template-transferred flexible substrate microstructure according to claim 1, wherein the microporous ceramic adsorption plate (1) has a high flatness (PV < 10 μm in general) and a small pore size (pore size < 2 μm in general), and is generally formed by high-temperature sintering and polished to control the surface shape.

3. The method for improving the position accuracy of the microstructure of the template transfer printing flexible substrate according to claim 1, wherein a seal is formed between the base (2) of the adsorption plate and the microporous ceramic adsorption plate (1), the air pressure adjusting pipeline (3) is generally composed of an air nozzle, an air pipe and a vacuum pump, when the microporous ceramic adsorption plate contacts the microstructure flexible substrate (4), the vacuum pump is started, the microstructure flexible substrate (4) is tightly attached to the microporous ceramic adsorption plate (1), the surface needs to be cleaned before adsorption, and the phenomenon that the attachment strength is reduced or the defect is caused by pollutants such as surface particles is avoided.

4. The method for improving the template-transferred flexible substrate microstructure position accuracy according to claim 1, wherein the bonding force between the microstructure flexible substrate (4) and the microstructure rigid template (5) is smaller than the bonding force between the microstructure flexible substrate (4) and the microporous ceramic adsorption plate (1), in order to achieve this, a surface pretreatment or a post-treatment method is usually adopted to reduce the bonding force between the microstructure flexible substrate (4) and the microstructure rigid template (5), the surface pretreatment usually can use a fluorine-containing compound coating or other coatings with lower surface energy, and the surface post-treatment usually can use the swelling property of the flexible substrate to reduce the bonding force.

5. The method for improving the position accuracy of the microstructure of the template transfer printing flexible substrate according to claim 1, wherein the rigid supporting frame (6) has better flatness, surface smoothness and higher rigidity, and is generally made of metal, ceramic and carbon fiber composite materials.

6. The method for improving the microstructure position accuracy of the template transfer printing flexible substrate according to claim 1, wherein the adhesive (7) can be firmly bonded with the rigid supporting frame (6) and the microstructure flexible substrate (4) at the same time, an epoxy adhesive or a polyester adhesive is generally adopted, the adhesive (7) is firstly uniformly coated on the surface of the rigid supporting frame (6), then the rigid supporting frame (6) is contacted with the microstructure flexible substrate (4), and after the adhesive (7) is completely cured, the vacuum of the microporous ceramic adsorption plate (1) is released.

Technical Field

The invention belongs to the field of micro-machining of flexible substrates, and particularly relates to a method for improving the position precision of a template transfer printing flexible substrate microstructure.

Background

In the field of fine processing of flexible substrates, a commonly adopted technical process is that a microstructure is formed on a rigid substrate (such as a silicon wafer, a glass sheet or a quartz sheet) through photoetching and etching process technologies, and then a microstructure pattern is copied onto the flexible substrate by utilizing an imprinting or casting process technology. However, due to the poor dimensional stability of the flexible substrate itself, shrinkage or expansion is inevitably caused during the replication process. Although the amount of change in the microstructure is usually small, the accumulation of the change macroscopically manifests itself in a decrease in the positional accuracy of the microstructure, which becomes a fatal defect, particularly when a flexible substrate is applied to a diffractive imaging element.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the invention provides a method for improving the position precision of a template transfer printing flexible substrate microstructure, which aims to ensure the position precision of the microstructure on a flexible substrate so as to be applied to a diffraction imaging element.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a method for improving the position accuracy of a template transfer printing flexible substrate microstructure utilizes a device comprising a microporous ceramic adsorption plate, an adsorption plate base, an air pressure adjusting pipeline, a microstructure flexible substrate, a microstructure rigid template, a rigid supporting frame and an adhesive. The microstructure rigid template is generally made of rigid substrates such as metal, ceramic and the like through a micro-nano processing technology, and the microstructure flexible substrate is generally made on the surface of the microstructure rigid template through a tape casting method or an imprinting method; the microporous ceramic adsorption plate is generally manufactured by sintering, polishing and other processes, and has high flatness and air permeability; the microporous ceramic adsorption plate is fixed on the adsorption plate base, a closed cavity is formed in the microporous ceramic adsorption plate, and air is pumped or inflated through an air pressure adjusting pipeline; the rigid supporting frame is generally molded and polished by rigid materials such as metal, ceramic or carbon fiber and the like, and the surface of the rigid supporting frame has higher flatness and smoothness; the adhesive is used for bonding the rigid support frame and the microstructure flexible substrate.

The microporous ceramic adsorption plate has high flatness (PV is less than 10 mu m generally), has small pores (aperture is less than 2 mu m generally), is generally formed by high-temperature sintering, and is polished to control the surface shape.

The adsorption plate base and the microporous ceramic adsorption plate form a seal, the air pressure adjusting pipeline is usually composed of an air nozzle, an air pipe and a vacuum pump, and when the microporous ceramic adsorption plate contacts the microstructure flexible substrate, the vacuum pump is started, and the microstructure flexible substrate is tightly attached to the microporous ceramic adsorption plate. It is worth noting that the surface is cleaned before adsorption, so as to avoid the reduction of the bonding force or the defect caused by pollutants such as surface particles.

The adsorption plate base and the microporous ceramic adsorption plate form a seal, the air pressure adjusting pipeline is usually composed of an air nozzle, an air pipe and a vacuum pump, and when the microporous ceramic adsorption plate contacts the microstructure flexible substrate, the vacuum pump is started, and the microstructure flexible substrate is tightly attached to the microporous ceramic adsorption plate. It is worth noting that the surface is cleaned before adsorption, so as to avoid the reduction of the bonding force or the defect caused by pollutants such as surface particles.

The binding force between the microstructure flexible substrate and the microstructure rigid template is required to be smaller than that between the microstructure flexible substrate and the microporous ceramic adsorption plate, and in order to realize the binding force, a surface pretreatment or post-treatment method is usually adopted to reduce the binding force between the microstructure flexible substrate and the microstructure rigid template. Surface pre-treatments may typically utilize fluorochemical coatings or other coatings with lower surface energy, and surface post-treatments may typically utilize the swelling properties of the flexible substrate to reduce bonding forces.

The rigid supporting frame has good flatness, surface smoothness and high rigidity, and is generally processed by metal, ceramic, carbon fiber composite materials and the like.

The adhesive can be firmly bonded with the rigid supporting frame and the microstructure flexible substrate at the same time, and the adhesives such as epoxy adhesives, polyester adhesives and the like are generally adopted. Firstly, uniformly coating the adhesive on the surface of the rigid support frame, then contacting the rigid support frame with the microstructure flexible substrate, and releasing the vacuum of the microporous ceramic adsorption plate after the adhesive is completely cured.

The working process is as follows: the method comprises the steps of transferring a microstructure flexible substrate from a microstructure rigid template to a microporous ceramic adsorption plate by using a vacuum adsorption mode, transferring the microstructure flexible substrate from the microporous ceramic adsorption plate to a rigid support frame by using an adhesive, and finally removing vacuum to complete transfer.

Compared with the prior art, the invention has the advantages that:

(1) the invention can realize the flexible substrate film lens in the true sense, gets rid of the constraint of the traditional rigid base and is beneficial to the light weight of the optical element.

(2) The invention can overcome the in-plane irreversible deformation caused by peeling the film firstly and then fixing the film, furthest maintains the precision of the microstructure position and is beneficial to the lossless retention of the optical wavefront.

(3) The microporous ceramic adsorption plate adopted by the invention has higher smoothness and flatness, ensures the surface quality and surface shape of the film to the maximum extent and is beneficial to the transfer printing precision.

Drawings

FIG. 1 is a schematic diagram of a microstructure flexible substrate transferred from a microstructure rigid template to a microporous ceramic adsorption plate;

FIG. 2 is a schematic diagram of a microstructure flexible substrate transferred from a microporous ceramic adsorption plate to a rigid support frame;

fig. 3 is a schematic diagram of a microstructure flexible substrate with a rigid supporting frame after the transfer is completed.

In the figure: the device comprises a microporous ceramic adsorption plate 1, an adsorption plate base 2, an air pressure adjusting pipeline 3, a microstructure flexible substrate 4, a microstructure rigid template 5, a rigid support frame 6 and an adhesive 7.

Detailed Description

The invention is further described with reference to the following figures and detailed description.

The invention relates to a method for improving the position precision of a template transfer printing flexible substrate microstructure, which utilizes a device comprising a microporous ceramic adsorption plate 1, an adsorption plate base 2, an air pressure adjusting pipeline 3, a microstructure flexible substrate 4, a microstructure rigid template 5, a rigid support frame 6 and an adhesive 7; the mutual relation is that the microporous ceramic adsorption plate 1, the adsorption plate base 2 and the air pressure adjusting pipeline 3 are integrated into a whole and have an adsorption function, the microstructure flexible substrate 4 and the microstructure rigid template 5 are integrated into a whole, the binding force between the microstructure flexible substrate and the microstructure rigid template is large, and the surface of the rigid support frame 6 is coated with an adhesive 7 and is bonded with the microstructure flexible substrate 4. The work flow is that firstly the micro-structure flexible substrate 4 is transferred to the micro-porous ceramic adsorption plate 1 from the micro-structure rigid template 5 by using a vacuum adsorption mode, then the micro-structure flexible substrate 4 is transferred to the rigid support frame 6 from the micro-porous ceramic adsorption plate 1 by using an adhesive 7, and finally the vacuum is removed to finish the transfer.

The microporous ceramic adsorption plate 1 has high flatness (PV is less than 10 μm generally), has small pores (aperture is less than 2 μm generally), is generally formed by high-temperature sintering, and is polished to control the surface shape.

Form between adsorption plate base 2 and the micropore ceramic adsorption plate 1 sealedly, atmospheric pressure adjusting pipe way 3 comprises air cock, trachea, vacuum pump usually, opens the vacuum pump after micropore ceramic adsorption plate contact micro-structure flexible substrate 4, and micro-structure flexible substrate 4 closely laminates with micropore ceramic adsorption plate 1 promptly. It is worth noting that the surface is cleaned before adsorption, so as to avoid the reduction of the bonding force or the defect caused by pollutants such as surface particles.

The bonding force between the microstructure flexible substrate 4 and the microstructure rigid template 5 needs to be smaller than the bonding force between the microstructure flexible substrate 4 and the microporous ceramic adsorption plate 1, and in order to achieve the bonding force, a surface pretreatment or post-treatment method is usually adopted to reduce the bonding force between the microstructure flexible substrate 4 and the microstructure rigid template 5. Surface pre-treatments may typically utilize fluorochemical coatings or other coatings with lower surface energy, and surface post-treatments may typically utilize the swelling properties of the flexible substrate to reduce bonding forces.

The rigid supporting frame 6 has good flatness, surface smoothness and high rigidity, and is generally made of metal, ceramic, carbon fiber composite materials and the like.

The adhesive 7 can be firmly bonded to both the rigid support frame 6 and the microstructure flexible substrate 4, and an adhesive such as epoxy or polyester is generally used. Firstly, uniformly coating the adhesive 7 on the surface of the rigid support frame 6, then contacting the rigid support frame 6 with the microstructure flexible substrate 4, and releasing the vacuum of the microporous ceramic adsorption plate 1 after the adhesive 7 is completely cured.