CN119045093A

CN119045093A - Preparation method of porous antireflection film, porous antireflection film and optical device

Info

Publication number: CN119045093A
Application number: CN202411232645.8A
Authority: CN
Inventors: 李翔; 袁红霞; 糜珂; 王娟
Original assignee: Jiangsu Leadmicro Nano Technology Co Ltd
Current assignee: Jiangsu Leadmicro Nano Technology Co Ltd
Priority date: 2024-09-03
Filing date: 2024-09-03
Publication date: 2024-11-29

Abstract

The present disclosure provides a method for preparing a porous antireflection film, and an optical device. The preparation method comprises the steps of preparing at least one first precursor monolayer and at least one second precursor monolayer on a substrate, reacting materials of the first precursor monolayer and materials of the second precursor monolayer to form a metal organic composite layer capable of being hydrolyzed, placing the metal organic composite layer in an aqueous environment for hydrolysis reaction so that the metal organic composite layer is converted into a porous metal oxide layer, and preparing a conformal layer used for reinforcing the porous metal oxide layer on the porous metal oxide layer. The preparation method of the porous antireflection film can improve the controllable degree of the pore structure, give consideration to the stability of the pore structure, simplify the preparation process of the porous antireflection film, and obtain the optical antireflection film with high transmittance.

Description

Preparation method of porous antireflection film, porous antireflection film and optical device

Technical Field

The invention relates to the technical field of films, in particular to a preparation method of a porous antireflection film, the porous antireflection film and an optical device.

Background

The optical antireflection film is an optical film with a very wide application range at present. The optical antireflection film is used for reducing reflected light on the surface of the optical device and increasing the light transmission quantity of the optical device. Conventional optical antireflection films utilize the principle of interference cancellation of light to achieve a reduction in reflected light and an increase in transmitted light. Conventional optical antireflection films typically include tens or even hundreds of films of different refractive indices that are matched by thickness and refractive index to achieve increased transmittance of light in a particular band. The optical antireflection film has complex structure and preparation process, can realize antireflection effect only in a limited wave band, and has poor durability and stability.

The porous antireflection film is a porous antireflection film which reduces the reflection of light at an interface by using a microporous structure of a material, thereby improving the transmittance. Through reasonable design micropore structure and regulation material parameter, can realize the refractive index regulation and control to specific wavelength light, and then realize effectual anti-reflection effect. The porous antireflection film is usually prepared by a template method, a sol-gel method, a template method or the like in the traditional technology. The sol-gel method refers to that precursor molecules in sol are gelled to form solid materials in the presence of a gelling agent, and then the solid materials are subjected to heat treatment to form pore structures, so that the structural stability of the prepared materials is poor due to higher process complexity. The template method refers to forming a pore structure by using a template agent, then filling a material into the pore structure of the template, and finally removing the template agent to obtain a porous material. The mode often needs to change the type of the template agent when the pore structure is regulated and controlled, and has higher process complexity and poorer controllability. Therefore, the problems of higher process complexity, insufficient controllable degree of pore structure, poor stability and the like often exist in the traditional technology, and further development and application of the porous antireflection film are limited.

Disclosure of Invention

Based on this, it is necessary to provide a preparation method of a porous antireflection film, which has low process complexity, can improve the controllable degree of the pore structure and has the stability of the pore structure.

According to some embodiments of the present disclosure, a method of preparing a porous anti-reflection film includes the steps of:

Preparing at least one first precursor monolayer and at least one second precursor monolayer on a substrate, wherein the materials of the first precursor monolayer and the second precursor monolayer react to form a metal-organic composite layer capable of being hydrolyzed;

subjecting the metal organic composite layer to hydrolysis reaction in an aqueous environment to convert the metal organic composite layer into a porous metal oxide layer, and

And preparing a conformal layer for reinforcing the porous metal oxide layer on the porous metal oxide layer.

In some embodiments of the present disclosure, the material of the conformal layer is selected from an oxide. The conformal layer is prepared by one or more methods of atomic layer deposition, molecular layer deposition, chemical vapor deposition, physical vapor deposition and liquid phase epitaxy.

In some embodiments of the present disclosure, the material of the conformal layer is selected from one or more of silicon oxide, aluminum oxide, and titanium oxide.

In some embodiments of the present disclosure, the conformal layer has a thickness of 10nm or less.

In some embodiments of the present disclosure, prior to preparing the conformal layer, a step of shaping the porous metal oxide layer is further included.

In some embodiments of the present disclosure, the step of shaping the porous metal oxide layer includes placing the porous metal oxide layer in a protective gas environment and heating the porous metal oxide layer.

In some embodiments of the present disclosure, the process of heating the porous metal oxide layer satisfies at least one of the following characteristics:

(1) The heating temperature is 50-80 ℃;

(2) The heating time is 5 min-10 min.

In some embodiments of the present disclosure, the process of performing the hydrolysis reaction satisfies at least one of the following characteristics:

(1) The temperature of the hydrolysis reaction is 10-80 ℃;

(2) The hydrolysis reaction time is 5 min-120 min.

In some embodiments of the present disclosure, the metal-organic composite layer is formed to a thickness of 5nm to 60nm.

In some embodiments of the present disclosure, the step of preparing the first precursor monolayer and the second precursor monolayer on the substrate comprises:

placing the substrate in a deposition chamber;

Introducing the material of the first precursor monolayer into the deposition chamber and attaching the material to the substrate to form the first precursor monolayer;

Introducing the material of the second precursor monolayer into the deposition chamber and attaching the material to the substrate to form the second precursor monolayer;

Wherein the deposition cycle is repeated a plurality of times with the step of forming the first precursor monolayer and the step of forming the second precursor monolayer as one deposition cycle.

In some embodiments of the present disclosure, the metal-organic composite layer comprises an aluminum-based organic-inorganic hybrid material, the material of the first precursor monolayer comprises a metal-organic compound, and the material of the second precursor monolayer comprises an alcohol-based organic compound and/or derivatives thereof.

In some embodiments of the present disclosure, the material of the first precursor monolayer comprises trimethylaluminum and the material of the second precursor monolayer comprises one or more of ethylene glycol, glycerol, and ethanolamine.

In some embodiments of the present disclosure, the process of preparing the first precursor monolayer and the second precursor monolayer on the substrate satisfies at least one of the following characteristics:

(1) The number of deposition cycles is 15-100;

(2) The temperature of the deposition chamber is 50-200 ℃.

Further, the disclosure also provides a porous antireflection film, which comprises a porous metal oxide layer and a conformal layer, wherein the conformal layer is attached to the pore structure of the porous metal oxide layer, and the porous antireflection film is prepared by the preparation method of the porous antireflection film according to any embodiment.

In some embodiments of the present disclosure, the porous metal oxide layer satisfies at least one of the following characteristics:

(1) The thickness of the porous metal oxide layer is 40 nm-100 nm;

(2) The pore diameter of the pores in the porous metal oxide layer is 35 nm-105 nm;

(3) The average light transmittance of the porous metal oxide layer in the wave band of 450-675 nm is more than 99%.

The present disclosure also provides an optical device comprising a workpiece body and a porous anti-reflection film disposed on the workpiece body, the porous anti-reflection film comprising a porous anti-reflection film as described in any one of the embodiments above. In the preparation method of the porous antireflection film, a metal organic composite layer is formed by combining a first precursor monomolecular layer and a second precursor monomolecular layer. And then the metal organic composite layer and water undergo hydrolysis reaction, so that the metal organic composite layer is converted into a porous metal oxide layer with a porous structure. Compared with the traditional preparation method of the porous antireflection film, the preparation method has obviously lower process complexity. The mode of combining and forming the metal organic composite layer and carrying out hydrolysis reaction on the metal organic composite layer can effectively improve the controllable degree of the pore structure. On the basis, the further formed conformal layer can also improve the air stability and the friction resistance of the porous metal oxide layer without basically changing the pore structure, so that the prepared porous antireflection film also has higher stability.

In addition, the preparation method has higher consistency, and the thickness of the metal organic composite layer, the temperature and time of hydrolysis reaction and the like are controlled by selecting the materials of the first precursor monolayer and the second precursor monolayer, so that the required porous structure can be customized and obtained.

The foregoing description is only an overview of the present invention, and is intended to provide a better understanding of the present invention, as it is embodied in the following description, with reference to the preferred embodiments of the present invention and the accompanying drawings.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and that other embodiments of the drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram showing steps of a method for preparing a porous antireflection film;

FIG. 2 is a photograph of the surface morphology of the sample before and after the setting treatment in example 1 after standing in air for a certain period of time, wherein the left graph is a photograph of the surface morphology of the sample before the setting treatment after standing for 20 hours, and the right graph is a photograph of the surface morphology of the sample after the setting treatment after standing for 100 hours;

FIG. 3 is a photograph of the surface topography of the samples prepared in example 1 and comparative example 1 after wiping with steel wool, wherein the left graph is a photograph of the surface topography of the sample of example 1 after wiping, and the right graph is a photograph of the surface topography of the sample of comparative example 1 after wiping;

FIG. 4 is a sample surface topography of example 1 observed using a scanning electron microscope;

FIG. 5 is a sample surface topography of example 2 observed using a scanning electron microscope;

FIG. 6 is a sample surface topography of example 3 observed using a scanning electron microscope;

FIG. 7 is a graph showing the transmittance as a function of the wavelength of incident light for example 1, wherein the abscissa indicates the wavelength in nm and the ordinate indicates the transmittance;

FIG. 8 is a graph showing the transmittance as a function of the wavelength of incident light for example 2, wherein the abscissa indicates the wavelength in nm and the ordinate indicates the transmittance;

fig. 9 is a graph showing the transmittance as a function of the wavelength of incident light for example 3, wherein the abscissa indicates the wavelength in nm and the ordinate indicates the transmittance.

Detailed Description

To facilitate an understanding of this document, a more complete description of this document will follow. Preferred embodiments herein are presented. This may be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description presented herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

It will be understood that when an element or layer is referred to as being "on," "adjacent," "connected to," or "coupled to" another element or layer, it can be directly on, adjacent, connected, or coupled to the other element or layer, or intervening elements or layers may also be present. In contrast, when an element is referred to as being "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" another element or layer, there are no intervening elements or layers present. It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section.

Spatially relative terms, such as "under", "below", "beneath", "under", "above", "over" and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and operation. For example, if the device in the figures is turned over, elements or features described as "under" or "beneath" other elements would then be oriented "on" the other elements or features. Thus, the exemplary terms "below" and "under" may include both an upper and a lower orientation. The device may be otherwise oriented (e.g., rotated 90 degrees or other orientations) and the spatial descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of the associated listed items.

The present disclosure provides a method of preparing a porous anti-reflection film comprising the steps of preparing at least one first precursor monolayer and at least one second precursor monolayer on a substrate, the material of the first precursor monolayer and the material of the second precursor monolayer reacting to form a metal-organic composite layer capable of hydrolysis. And placing the metal organic composite layer in an aqueous environment for hydrolysis reaction so that the metal organic composite layer is converted into a porous metal oxide layer. And preparing a conformal layer on the porous metal oxide layer for reinforcing the porous metal oxide layer.

Wherein in an actual manufacturing process the first precursor monolayer and the second precursor monolayer may be formed by attaching a monolayer of molecules to the matrix material. It will be appreciated that the first precursor monolayer and the second precursor monolayer may be chemically bonded to form a metal-organic composite layer, the material of which is capable of undergoing hydrolysis and formation of an oxide of the metal. The hydrolysis reaction of the metal organic composite layer with water gradually decomposes the material of the metal organic composite layer and causes a structural change of the metal organic composite layer, thereby generating a pore structure. The present disclosure has found during the course of research that the pore structure and pore size are closely related to the conditions (e.g., time and temperature) of the hydrolysis reaction. By controlling the conditions of the hydrolysis reaction, the surface hydrolysis rate of the metal organic composite layer can be controlled, thereby realizing the accurate control of the pore structure and the pore size in the porous metal oxide layer.

In the preparation method of the porous antireflection film, a metal organic composite layer is formed by combining a first precursor monomolecular layer and a second precursor monomolecular layer. Because the first precursor monolayer and the second precursor monolayer are prepared and react by the monolayer, the interference of random factors can be effectively avoided, the reproduction is easy, and the structure of the metal organic composite layer is highly controllable and has higher reproducibility. And then, carrying out hydrolysis reaction on the metal organic composite layer and water, so that the metal organic composite layer is converted into a porous metal oxide layer with a porous structure. The pore structure in the porous metal oxide layer is related to the structure of the metal organic composite layer and the hydrolysis condition, and the accurate control of the pore structure and the size can be realized by controlling the hydrolysis condition and the structure of the metal organic composite layer. Therefore, the controllable degree of the pore structure can be effectively improved by combining the metal organic composite layer and the hydrolysis reaction mode. On the basis, the further formed conformal layer can also improve the air stability and the friction resistance of the porous metal oxide layer without basically changing the pore structure, so that the prepared porous antireflection film also has higher stability.

Compared with the traditional preparation methods such as a template method or a sol-gel method, the preparation method of the porous antireflection film disclosed by the invention is prepared by depositing a molecular layer, so that the rapid, efficient and large-area preparation of the porous antireflection film can be realized. The preparation process is simplified and the preparation efficiency is high. The preparation method of the porous antireflection film can be used for preparing on a plurality of different substrates, and can also realize the regional selective generation of the porous antireflection film by combining a selective deposition technology, so as to meet different application requirements. Further, experiments prove that the porous antireflection film prepared by the preparation method of the porous antireflection film disclosed by the invention has an excellent antireflection effect.

Fig. 1 is a schematic step diagram of a method for preparing a porous antireflection film according to the present disclosure. Referring to fig. 1, the preparation method of the porous antireflection film includes steps S1 to S3, specifically as follows.

Step S1, preparing at least one first precursor monolayer and at least one second precursor monolayer on a substrate.

As some examples of this embodiment, the substrate may be a workpiece to be prepared with a porous antireflection film. The workpiece may be, but is not limited to, an optical lens. The material of the optical lens can be organic glass or inorganic glass. As an example, the organic glass is plexiglass and the inorganic glass is K9 glass.

In this embodiment, the material of the first precursor monolayer and the material of the second precursor monolayer react to form a metal-organic composite layer capable of hydrolysis. The metal organic composite layer contains metal organic composite material, and the metal organic composite material is formed by combining metal atoms with carbon chains of organic matters. The metal atoms are able to combine with hydroxyl groups in the water upon hydrolysis to form metal-hydroxyl compounds and ultimately to form metal oxides.

As some examples of this embodiment, the metal organic composite layer includes an aluminum-based organic-inorganic hybrid material.

It will be appreciated that the materials of the first precursor monolayer and the second precursor monolayer may be selected accordingly depending on the desired metal-organic composite layer. As some examples of this embodiment, the first precursor monolayer comprises a metal-organic compound and the second precursor monolayer comprises an alcohol-based organic compound and/or derivatives thereof.

As some examples of this embodiment, in the first precursor monolayer, the metal-organic compound may be a metal alkyl compound. In this example, the metal atom in the metal alkyl compound may be selected from one or more of aluminum, gallium, indium, tin, lead, zinc, titanium, and cobalt. In this example, there may be one or more alkyl groups depending on the number of coordination of the metal atoms in the metal alkyl compound. The alkyl group may be selected from alkyl groups having 1 to 20 carbon atoms, and for example, the alkyl group may be methyl, ethyl, propyl, butyl, or the like.

Further, the metal organic compound in the first precursor monolayer is trimethylaluminum. It will be appreciated that in other examples, the metal organic compound may also be, but is not limited to, triethylaluminum, tetramethyltin, dimethylzinc, and the like.

Further, the alcohol organic in the second precursor monolayer may be selected from one or more of ethylene glycol, glycerol, and ethanolamine.

In other examples, the alcohol organic matter may also be selected from one or more of glycols such as propylene glycol, butylene glycol, and pentylene glycol. The derivative of the alcohol organic substance refers to an alcohol organic substance in which at least one hydrogen atom is substituted.

In the method, trimethylaluminum and dihydric alcohol are taken as examples, and trimethylaluminum and dihydric alcohol can react to form an aluminum alkoxide compound, and the aluminum alkoxide compound is used as a material of the metal organic composite layer.

As some examples of this embodiment, both the first precursor monolayer and the second precursor monolayer have multiple layers. It will be appreciated that the provision of multiple first precursor monolayers and multiple second precursor monolayers enables thicker metal-organic composite layers to be formed. Further, by controlling the number of layers of the first precursor monolayer and the second precursor monolayer, the thickness of the metal-organic composite layer formed can be controlled. This also facilitates precise control over the overall structure of the final porous metal oxide layer.

As some examples of this embodiment, the step of preparing the first precursor monolayer and the second precursor monolayer on the substrate includes placing the substrate in a deposition chamber. The material of the first precursor monolayer is introduced into the deposition chamber and attached to the substrate to form the first precursor monolayer. A second precursor monolayer is formed by introducing material of the second precursor monolayer into the deposition chamber and attaching it to the substrate. Wherein the step of forming a first precursor monolayer and the step of forming a second precursor monolayer are repeated as one deposition cycle.

For example, a first precursor monolayer is formed on the substrate prior to the first precursor monolayer being attached to the substrate. Then, a second precursor monolayer is formed which adheres to and is reactive with the previously prepared first precursor monolayer. Then, the first precursor monolayer and the second precursor monolayer are alternately deposited until a predetermined number of layers. The post-deposited first precursor monolayers are each attached to the previously deposited second precursor monolayer, and the post-deposited second precursor monolayers are each also attached to the previously deposited first precursor monolayer. The multiple first precursor monolayers and the multiple second precursor monolayers are combined to form a metal-organic composite layer.

As some examples of this embodiment, the step of purging the deposition chamber may be included after each formation of the first precursor monolayer and the second precursor monolayer. The step of purging the deposition chamber includes introducing a protective gas into the deposition chamber to remove unreacted materials and byproducts from the reaction, ensuring the purity of the surface to ensure continued deposition.

It is understood that in this embodiment, the process of preparing the first precursor monolayer and the second precursor monolayer on the substrate may be performed using a molecular layer deposition (Molecular Layer Deposition) apparatus.

As some examples of this embodiment, the metal organic composite layer is formed to a thickness of 5nm to 60nm.

In this example, the thickness of the metal organic composite layer is 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm. Or the thickness of the metal organic composite layer can be between any two of the above thicknesses. The metal organic composite layer with the thickness is favorable for forming a porous metal oxide layer with a relatively stable pore structure and relatively good light transmittance in the subsequent hydrolysis process.

It will be appreciated that the thickness of the metal organic composite layer may be controlled by controlling the number of deposition cycles to correspond to the control.

As some examples of this embodiment, the number of deposition cycles may be 15-100. That is, 15 to 100 monolayers of the first precursor and 15 to 100 monolayers of the second precursor are alternately deposited. For example, the number of deposition cycles may be 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100, or the number of deposition cycles may be between any two of the above.

As some examples of this embodiment, the temperature of the deposition chamber is 50 ℃ to 200 ℃ during the formation of the first precursor monolayer and the second precursor monolayer. Controlling the temperature of the deposition chamber between this range helps to allow the first precursor monolayer to adhere more fully and uniformly and to allow the process of combining the first precursor monolayer with the second precursor monolayer to form the metal-organic composite layer to be more controlled, thereby increasing the degree of controllability of the pore structure in the subsequently formed porous metal oxide layer.

In this method of preparation, the first precursor monolayer and the second precursor monolayer may be deposited at a lower temperature and thus are also particularly suitable for preparation on certain substrates that are less resistant to high temperatures. For a substrate with poor high temperature resistance, the temperature of the deposition chamber may be 50 ℃ to 100 ℃ during the formation of the first precursor monolayer and the second precursor monolayer. For example, the temperature of the deposition chamber may be 50 ℃,60 ℃, 70 ℃, 80 ℃, 90 ℃, 100 ℃. Or the temperature of the deposition chamber may be between any two of the above temperatures.

And S2, placing the metal organic composite layer in an aqueous environment for hydrolysis reaction so that the metal organic composite layer is converted into a porous metal oxide layer.

In this embodiment, the material of the porous metal oxide layer includes a metal oxide, and the metal element in the metal oxide is the metal element in the metal organic composite layer.

As some examples of this embodiment, the metal organic composite layer may be placed in water to perform a hydrolysis reaction. Or in other examples, the metal organic composite layer may be placed in a humid gas environment containing water vapor to perform the hydrolysis reaction.

Here, taking the hydrolysis reaction of an aluminum alkoxide compound as an example, the aluminum alkoxide compound (Al-O-CH ₂-CH₂ -O-Al) reacts with water to form an aluminum hydroxide compound (Al-OH), and the chemical reaction formula is Al-O-CH ₂-CH₂-O-Al+H₂O→Al-OH+HO-CH₂-CH₂ -O-Al. Wherein the aluminum hydroxide compound is further dehydrated to form aluminum oxide. In addition, the hydroxyl group can generate alkyd radical ions RO ^- (R represents a group connected with the hydroxyl group) when being hydrolyzed, the chemical reaction formula is ROH+H ₂O→RO^-+H₃O⁺, and the alkyd radical ions can further react with water in the presence of carbon dioxide to generate carboxylic acid (RCOOH), and the chemical reaction formula is RO ^-+CO+H₂O→RCOOH+OH^-. Thus, the aluminum alkoxide polymer can be gradually converted into a porous alumina material having hydroxyl and carboxyl functional groups on the surface thereof through a hydrolysis reaction.

As some examples of this embodiment, the temperature of the hydrolysis reaction may be controlled to be 10 ℃ to 80 ℃ during the hydrolysis reaction. Controlling the temperature of the hydrolysis reaction allows for a more optimal hydrolysis reaction rate, which facilitates more precise control of the pore structure obtained. When the temperature of the hydrolysis reaction is low, the hydrolysis reaction rate is too slow, which is unfavorable for the formation of a porous structure. When the temperature of the hydrolysis reaction is higher, the hydrolysis reaction rate is too high, which is unfavorable for more accurate control of the porous structure.

In this example, the temperature of the hydrolysis reaction may be controlled to be 10 ℃, 15 ℃, 20 ℃, 25 ℃, 30 ℃, 35 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃, 80 ℃, or the temperature of the hydrolysis reaction may also be controlled to be between any two of the above temperatures.

As some examples of this embodiment, the hydrolysis reaction time may be controlled to be 5 min-120 min. The control of the hydrolysis reaction time is beneficial to the control of the hydrolysis reaction progress, and the regulation and control of pore size, shape, arrangement mode and the like can be realized, so that the porous metal oxide layer with the controllable pore structure is prepared. And the time of the hydrolysis reaction is also favorable for obtaining a porous metal oxide layer with significantly higher transmittance.

In this example, the time of the hydrolysis reaction may be controlled to 5min、10min、15min、20min、25min、30min、35min、40min、45min、50min、60min、70min、80min、90min、100min、110min、120min. or may be controlled to be between any two of the above.

It will be appreciated that when the temperature of the hydrolysis reaction is higher, the rate of hydrolysis reaction is faster and the time of hydrolysis reaction can be controlled to be shorter, i.e. to be able to form the desired pore structure. When the temperature of the hydrolysis reaction is low, the hydrolysis reaction rate is slow, and the time of the hydrolysis reaction can be controlled to be long to form a desired pore structure. In addition, the time of the hydrolysis reaction can be correspondingly controlled according to the thickness of the metal organic composite layer. For example, for thicker metal organic composite layers, longer hydrolysis reaction times may be employed to ensure that the metal organic composite layer is more fully hydrolyzed to a porous metal oxide layer.

As some examples of this embodiment, after the hydrolysis reaction, a step of drying the formed porous metal oxide layer is further included. The drying treatment is used to remove the residual moisture in the porous metal oxide layer.

In this example, the drying process is performed by purging the porous metal oxide layer with a protective gas.

In this embodiment, the porous metal oxide layer produced by the hydrolysis reaction also has a problem of poor stability of the pore structure, which results in that the pore structure of the layer is easily broken and easily detached from the surface of the substrate. As some examples of this embodiment, after the porous metal oxide layer is formed, a step of subjecting the porous metal oxide layer to a shaping treatment may be further included.

In this example, the step of shaping the porous metal oxide layer includes placing the porous metal oxide layer in a protective gas environment and heating the porous metal oxide layer. By heating the porous metal oxide layer, the pore structure can be shaped and the bonding strength between the porous metal oxide layer and the substrate can be enhanced.

In this example, the heating temperature is 50 ℃ to 80 ℃ when heating the porous metal oxide layer. For example, the heating temperature may be 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃, or the heating temperature may also be in a range between any two of the above.

As some examples of this embodiment, when heating the porous metal oxide layer, the heating time is 5min to 10min. For example, the heating time may be 5min, 6min, 7min, 8min, 9min, 10min, or the heating time may be in a range between any two of the above.

And S3, preparing a conformal layer for reinforcing the porous metal oxide layer on the porous metal oxide layer.

In this embodiment, the conformal layer covers the surface of the porous metal oxide layer. It will be appreciated that the surface of the porous metal oxide layer is porous and the conformal layer may be attached to the walls of the pores therein. The conformal layer can strengthen the pore structure of the porous metal oxide layer, so that the porous metal oxide layer can maintain the pore structure when facing external forces such as friction. And the conformal layer also enables stable attachment of the porous metal oxide layer to the substrate.

As some examples of this embodiment, the material of the conformal layer is selected from oxides. The oxide is structurally similar to the porous metal oxide layer material, which enables a tighter bond between the conformal layer and the porous metal oxide layer.

In this example, the material of the conformal layer may be selected from one or more of titanium dioxide, aluminum oxide, and silicon dioxide.

In this example, the material of the conformal layer is the same as the material of the porous metal oxide layer.

As some examples of this embodiment, the thickness of the conformal layer is 10nm or less. The adoption of the conformal layer with the thickness below 10nm can avoid the conformal layer from filling up the pore structure as much as possible and maintain the original pore structure in the porous metal oxide layer. Wherein, optionally, the thickness of the conformal layer may be 1 nm-3 nm. This is advantageous in achieving better shape retention properties while not substantially altering the pore structure.

In this example, the thickness of the conformal layer may be 1nm, 1.5nm, 2nm, 2.5nm, 3nm, or the thickness of the conformal layer may be between any two of the above.

As some examples of this embodiment, the conformal layer is prepared on the porous metal oxide layer in a manner selected from one or more of Chemical Vapor Deposition (CVD), physical Vapor Deposition (PVD), atomic Layer Deposition (ALD), molecular layer deposition, and liquid phase epitaxy. Preferably, atomic layer deposition is used to produce a conformal layer that is thinner and more uniform in thickness, while providing better conformal capabilities while minimizing the impact on light transmission properties.

It is understood that a porous antireflection film can be formed by steps S1 to S3.

Further, the present disclosure also provides a porous antireflection film, which may be prepared by the preparation method in the above embodiment.

As some examples of this embodiment, a porous anti-reflection film includes a porous metal oxide layer and a conformal layer attached to walls of the porous metal oxide layer. The porous metal oxide layer may be prepared by using the preparation method in the above embodiment.

As some examples of this embodiment, the porous antireflection film has an average light transmittance of 99% or more in a wavelength band of 450nm to 675 nm.

As some examples of this embodiment, the thickness of the porous metal oxide layer is 40nm to 100nm.

As some examples of this embodiment, the pores in the porous metal oxide layer have a pore size of 35nm to 105nm.

Further, the present disclosure also provides an optical device including a workpiece body and a porous anti-reflection film disposed on the workpiece body. The porous antireflection film is the porous antireflection film in the above embodiment.

As some examples of this embodiment, the optical device may be an imaging device, such as a display, the workpiece body of the display including a panel glass, and the porous anti-reflection film may be disposed on the panel glass of the display.

As some examples of this embodiment, the optical device may be a projection apparatus, such as a projector, the workpiece body of which includes a lens, and the porous antireflection film may be provided on the lens of the projector.

As some examples of this embodiment, the optical device may further include an image pickup apparatus, such as a camera, the work body of which includes a lens, and the porous antireflection film may be provided on the lens.

The present disclosure also provides the following examples to further illustrate some implementations of the above preparation methods. Accordingly, the present disclosure also provides the following comparative examples to illustrate the advantages of this preparation method.

Example 1

Using K9 glass as a substrate, the substrate was placed in a deposition chamber of a molecular layer deposition apparatus.

The temperature in the deposition chamber is controlled to be 120 ℃, trimethylaluminum is introduced into the deposition chamber to enable the trimethylaluminum to be attached to the substrate to form a first precursor monomolecular layer, and then argon is introduced into the deposition chamber to purge the deposition chamber to remove unattached trimethylaluminum and other byproducts and the like. And then ethylene glycol is introduced into the deposition chamber to enable the ethylene glycol to be attached to the first precursor monolayer, and argon is introduced into the deposition chamber to purge the deposition chamber to remove unattached ethylene glycol and other byproducts and the like. The steps of introducing trimethylaluminum and ethylene glycol are repeated for 50 times to form an aluminum alkoxide polymer which is used as a metal organic composite layer.

And immersing the substrate in pure water for hydrolysis reaction, wherein the water temperature is controlled to be 50 ℃, and the hydrolysis time is 45min, so that the porous metal oxide layer is formed. Taking out after hydrolysis, and purging for 2min by adopting a nitrogen gun until no residual water stain exists on the surface.

The substrate was transferred to an oven at 75 ℃ and heated for 10min to set the pore structure.

The substrate was transferred to a deposition chamber of an atomic layer deposition apparatus and an alumina material with a thickness of 2nm was deposited as a conformal layer.

Example 2

Example 2 is substantially the same as example 1 except that the step of introducing trimethylaluminum and ethylene glycol is repeated 75 times in the preparation of the metal organic composite layer, and the water temperature is controlled to be 30C and the hydrolysis time is controlled to be 60min in the hydrolysis reaction.

Example 3

Example 3 was substantially the same as example 1 except that the procedure of introducing trimethylaluminum and ethylene glycol was repeated 40 times at the time of preparing the metal-organic composite layer, and the water temperature was controlled to 10℃and the hydrolysis time was 100 minutes at the time of performing the hydrolysis reaction.

Example 4

Example 4 was substantially the same as example 1 except that polymethyl methacrylate was used as a substrate, the step of introducing trimethylaluminum and ethylene glycol was repeated 80 times in the preparation of the metal organic composite layer, and the water temperature was controlled to 30℃and the hydrolysis time was 60 minutes in the hydrolysis reaction.

Example 5

Example 5 is substantially the same as example 1 except that glycerol is used instead of ethylene glycol in the preparation of the metal organic composite layer, the steps of introducing trimethylaluminum and glycerol are repeated 100 times, the water temperature is controlled to be 50 ℃ in the hydrolysis reaction, the hydrolysis time is 30min, and the titanium dioxide material with a thickness of 2nm is deposited in the preparation of the conformal layer.

Example 6

Example 6 is substantially the same as example 1 except that polycarbonate is used as a substrate, ethanol amine is used instead of ethylene glycol in the preparation of the metal organic composite layer, and the steps of introducing trimethylaluminum and ethanol amine are repeated 90 times, water temperature is controlled to 80 deg.c in the hydrolysis reaction, hydrolysis time is 5min, and a silicon dioxide material having a thickness of 2nm is deposited in the preparation of the conformal layer.

Example 7

Example 7 is substantially the same as example 1 except that, in preparing the conformal layer, the substrate is transferred to a deposition chamber of a chemical vapor deposition apparatus, and an alumina material having a thickness of 2nm is deposited by a chemical vapor deposition method.

Example 8

Example 8 is substantially the same as example 1 except that, in the preparation of the conformal layer, the substrate is transferred to a deposition chamber of a magnetron sputtering apparatus and an alumina material having a thickness of 2nm is deposited by a magnetron sputtering method.

Example 9

Example 9 is essentially the same as example 1 except that in the preparation of the conformal layer, an alumina material is deposited to a thickness of 5 nm.

Example 10

Example 10 is essentially the same as example 1 except that an alumina material having a thickness of 0.5nm is deposited in the preparation of the conformal layer.

Example 11

Example 11 is essentially the same as example 1 except that no heating step is performed to set the pore structure after hydrolysis and prior to the preparation of the conformal layer.

Example 12

Example 12 is essentially the same as example 1, except that the hydrolysis temperature is 100 ℃.

Example 13

Example 13 is essentially the same as example 1, except that the hydrolysis time is 200min.

Comparative example 1

Comparative example 1 is substantially the same as example 1 except that the step of preparing the conformal layer is not performed after heating to set the pore structure.

Comparative example 2

Comparative example 2 is substantially the same as example 1 except that after the metal-organic composite layer was formed, the substrate was directly transferred into a muffle furnace and heated to 500 deg.c under an air atmosphere to be calcined, and then an alumina material having a thickness of 2nm was deposited on the surface of the calcined material.

Test 1 two samples of example 1 before and after the setting treatment were taken, respectively, and after standing in air for a certain period of time, the surface morphology change of the samples was observed with a microscope, and the results can be seen in fig. 2. The left graph in fig. 2 is a surface topography photograph of the sample after standing for 20 hours before the setting treatment, and the right graph in fig. 2 is a surface topography photograph of the sample after standing for 100 hours after the setting treatment.

Referring to fig. 2, it can be seen that the film layer on the surface of the substrate had localized bubbling, cracking and peeling after 20 hours of standing without the setting treatment, and the film layer on the surface of the substrate was not significantly abnormal even after 100 hours of standing. This means that the porous metal oxide layer can be effectively kept stable in pore structure by means of heat baking.

Test 2 samples prepared in example 1 and comparative example 1 were taken, and after wiping with steel wool, the surface morphology change of the samples was observed with a microscope, and the results can be seen in fig. 3. The left graph in fig. 3 is a photograph of the surface topography of the sample of example 1 after wiping, and the right graph in fig. 3 is a photograph of the surface topography of the sample of comparative example 1 after wiping.

Referring to fig. 3, it can be seen that the shape-retaining layer was not prepared in comparative example 1, and the surface film layer of comparative example 1 was subject to bubbling, cracking and peeling after wiping. In example 1, however, the surface film layer of example 1 did not suffer from the problem of bubbling and falling off even after wiping with steel wool, as compared to comparative example 1, in which the conformal layer was not further prepared, in which the conformal layer was further prepared on the basis of the porous metal oxide layer. This demonstrates that the design of the conformal layer structure can effectively ensure the structural stability of the porous metal oxide layer.

Test 3 the surface topography of the samples of examples 1 to 3 was observed by scanning electron microscopy, and the results are shown in fig. 4 to 6. Wherein fig. 4 is the surface morphology of the sample of example 1, fig. 5 is the surface morphology of the sample of example 2, and fig. 6 is the surface morphology of the sample of example 3.

Referring to fig. 4 to 6, examples 1 to 3 respectively employ different deposition cycles and different hydrolysis conditions, so that a porous metal oxide layer having a specific pore structure can be prepared. In FIG. 4, the pore size distribution of the porous structure is 35nm to 105 nm. In fig. 5, the pore size distribution of the porous structure is 62nm to 90 nm. In fig. 6, the pore size distribution of the porous structure is 75nm to 95 nm. This means that the pore structure is related to the thickness of the metal-organic composite layer and the hydrolysis conditions, and that the pore structure can be controlled correspondingly by controlling the thickness of the metal-organic composite layer and the hydrolysis conditions. Further, the hydrolysis temperature of example 1 was 50 ℃, and since the hydrolysis temperature was higher, the hydrolysis rate was faster, and the hydrolysis was more sufficient at 45 minutes. But the correspondingly formed holes are more non-uniform in size and therefore have a larger range of pore size distribution. The hydrolysis temperature of example 2 was 30 ℃, and the hydrolysis was sufficient only when the hydrolysis was carried out for 60 min. The uniformity of the pore size is improved, and the pore size distribution range is reduced compared with that of the embodiment 1. The hydrolysis temperature of example 3 was 10 ℃, the hydrolysis rate was slower, and hydrolysis for 100min was sufficient. The uniformity of the pore size is higher than that of example 2, and the pore size distribution range is further reduced than that of example 2.

Test 4 the porous antireflection films prepared in each example and comparative example were tested for average transmittance between 450nm and 675nm, and the surface morphology was observed after each example and comparative example were left to stand in air for 20 hours, and then the surface morphology was observed after wiping the surface with steel wool, and the results are shown in table 1. The transmittance curves of examples 1 to 3 according to the wavelength of the incident light are shown in fig. 7 to 9, respectively.

TABLE 1

In the column of the surface morphology after standing in table 1, "v" indicates that the film was flat and free from cracking abnormality, "o" indicates that a slight crack was seen in the film surface. In the column of the surface morphology after wiping in table 1, "v" indicates that the film did not suffer from the problem of bubble shedding, "o" indicates that the film had a small number of bubbles shedding, and "×" indicates that the film had a large area of bubble shedding.

Referring to fig. 7 to 9 and table 1, the porous antireflection films prepared in examples 1 to 3 can maintain the average transmittance at the wavelength band of 450nm to 6755 nm at 99% or more. Referring to table 1, the average transmittance of the porous antireflection films prepared in examples 1 to 6 can reach 99% or more, and it is explained that the preparation method of the present disclosure can prepare a porous antireflection film with a transmittance of 99% or more by hydrolyzing the metal-organic composite layer and then preparing the conformal layer.

Further, in table 1, comparative example 1 did not prepare a conformal layer as compared to example 1, and although example 1 and comparative example 1 had similar average light transmittance, there was a problem that large area bubbles were peeled off from the surface of comparative example 1, resulting in that the film of comparative example 1 was not suitable for practical use. This also illustrates that the formation of a thin conformal layer by atomic layer deposition does not significantly adversely affect the light transmittance of the porous metal oxide layer. Comparative example 2, although a porous metal oxide layer could be formed by direct firing, the transmittance of the prepared film was significantly lower. This also demonstrates that the preparation method of the present disclosure can prepare a porous antireflection film having significantly higher light transmittance.

Reference is also made to examples 1 and 12 and 13. In example 13, the transmittance of the porous antireflection film was reduced by using a higher hydrolysis temperature and a longer hydrolysis time period than in example 1. This is mainly because the degree of hydrolysis is too deep, which has a negative effect on the light transmittance of the porous structure.

Reference is made to example 1 and example 11. Compared with example 1, example 11 was not baked before the preparation of the conformal layer, resulting in a small crack on the surface after the placement, which not only has a negative effect on the structural stability of the porous anti-reflection film, but also results in a decrease in the light transmittance of the porous anti-reflection film.

Reference is made to example 1 and examples 7 and 8. The transmittance of examples 7 and 8 is significantly reduced compared to example 1, mainly because example 7 uses chemical vapor deposition to prepare the conformal layer and example 8 uses physical vapor deposition to prepare the conformal layer, and the uniformity of the conformal layers prepared by both methods is poor, which affects the original transmittance of the porous structure.

Reference is made to examples 1, 9 and 10. The conformal layer of example 9 was slightly thicker, which had a negative effect on the light transmission properties of the pore structure, resulting in a decrease in the light transmission of the porous anti-reflection film. The shape-retaining layer of example 10 was slightly thinner, and the porous antireflection film had substantially the same light transmittance as that of example 1, but the film was likely to undergo slight bubbling and peeling after wiping, and had slightly inferior structural stability.

Note that the above embodiments are for illustrative purposes only and are not meant to be limiting herein.

It should be understood that the steps are not strictly limited to the order of execution unless explicitly recited herein, and the steps may be executed in other orders. Moreover, at least a portion of the steps in the preparation process may include a plurality of sub-steps or stages, which are not necessarily performed at the same time, may be performed at different times, may not necessarily be performed sequentially, and may be performed alternately or alternately with at least a portion of the sub-steps or stages of other steps or other steps.

In this specification, each embodiment is described in a progressive manner, and each embodiment is mainly described by differences from other embodiments, and identical and similar parts between the embodiments are all enough to be referred to each other.

The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

Claims

1. The preparation method of the porous antireflection film is characterized by comprising the following steps of:

2. The method for preparing the porous antireflection film according to claim 1, wherein the material of the conformal layer is selected from the group consisting of oxides, and the conformal layer is prepared by one or more of atomic layer deposition, molecular layer deposition, chemical vapor deposition, physical vapor deposition and liquid phase epitaxy.

3. The method of claim 1, wherein the conformal layer is formed from a material selected from one or more of silicon oxide, aluminum oxide, and titanium oxide.

4. The method for preparing a porous antireflection film according to claim 1, wherein the thickness of the conformal layer is 10nm or less.

5. The method for preparing a porous antireflection film according to any one of claims 1 to 4, further comprising a step of shaping the porous metal oxide layer before preparing the conformal layer.

6. The method of claim 5, wherein the step of shaping the porous metal oxide layer comprises placing the porous metal oxide layer in a protective gas atmosphere and heating the porous metal oxide layer.

7. The method of claim 6, wherein the step of heating the porous metal oxide layer satisfies at least one of the following characteristics:

(1) The heating temperature is 50-80 ℃;

(2) The heating time is 5 min-10 min.

8. The method for producing a porous antireflection film according to any one of claims 1 to 4 and 6 to 7, wherein the hydrolysis reaction is carried out in a process satisfying at least one of the following characteristics:

(1) The temperature of the hydrolysis reaction is 10-80 ℃;

(2) The hydrolysis reaction time is 5 min-120 min.

9. The method for producing a porous antireflection film according to any one of claims 1 to 4 and 6 to 7, wherein the thickness of the metal-organic composite layer is 5nm to 60nm.

10. The method of preparing a porous anti-reflection film according to claim 9, wherein the step of preparing a first precursor monolayer and a second precursor monolayer on the substrate comprises:

placing the substrate in a deposition chamber;

11. The method according to claim 10, wherein the metal-organic composite layer comprises an aluminum-based organic-inorganic hybrid material, the material of the first precursor monolayer comprises a metal-organic compound, and the material of the second precursor monolayer comprises an alcohol organic compound and/or a derivative thereof.

12. The method of claim 11, wherein the material of the first precursor monolayer comprises trimethylaluminum and the material of the second precursor monolayer comprises one or more of ethylene glycol, glycerol, and ethanolamine.

13. The method of any one of claims 10-12, wherein the process of preparing the first precursor monolayer and the second precursor monolayer on the substrate satisfies at least one of the following characteristics:

(1) The number of deposition cycles is 15-100;

(2) The temperature of the deposition chamber is 50-200 ℃.

14. A porous antireflection film, characterized by comprising a porous metal oxide layer and a conformal layer, wherein the conformal layer is attached to a pore structure of the porous metal oxide layer, and the porous antireflection film is prepared by the preparation method of the porous antireflection film according to any one of claims 1-13.

15. The porous anti-reflection film according to claim 14, wherein the porous metal oxide layer satisfies at least one of the following characteristics:

(1) The thickness of the porous metal oxide layer is 40 nm-100 nm;

16. An optical device, comprising a workpiece body and a porous antireflection film disposed on the workpiece body, wherein the porous antireflection film comprises the porous antireflection film according to any one of claims 14 to 15.