Manufacturing method of ultrathin flexible glass

Abstract

The invention discloses a manufacturing method of ultra-thin flexible glass, and belongs to the technical field of glass manufacturing, the manufacturing method of the ultra-thin flexible glass comprises the following steps: taking a metal sheet as a substrate, taking silicon dioxide as a target material, carrying out magnetron sputtering to obtain a metal sheet with a silicon dioxide film after the magnetron sputtering is finished, and carrying out vacuum drying on the metal sheet to obtain the ultra-thin flexible glass. The metal sheet with the silicon dioxide film is soaked in an acid solution, an ultrathin flexible glass film suspended in the acid solution is obtained, the ultrathin flexible glass is obtained after cleaning and drying, the thickness of the ultrathin flexible glass ranges from 10 nm to 500 nm, the thickness is uniform, and the thickness uniformity deviation ranges from + / -1 nm to + / -2 nm. The ultra-thin flexible glass can be used as a key material of a flexible touch panel, high-flexibility and light and thin design of the touch panel is achieved, the touch operation experience of a user is improved, the application scene of a product is expanded, and the ultra-thin flexible glass can be applied to flexible touch equipment such as a foldable mobile phone, a tablet personal computer and an intelligent watch.

Description

Technical Field

[0001] This invention belongs to the field of glass manufacturing technology, and in particular relates to a method for manufacturing ultrathin flexible glass. Background Technology

[0002] The existing methods for preparing ultrathin flexible glass and their limitations are as follows:

[0003] 1. Float glass manufacturing process:

[0004] Float glass production involves floating molten glass on the surface of molten tin. By controlling parameters such as the temperature, flow rate, and drawing speed of the molten glass, the glass is flattened and cooled to form its shape. However, this method faces numerous challenges in producing ultra-thin glass. As the glass thickness decreases, its stability on the molten tin deteriorates, easily leading to problems such as uneven thickness and reduced surface quality. For example, when the glass thickness is less than 1 mm, even minor fluctuations during production can cause thickness deviations exceeding ±10 μm, failing to meet the requirements of some high-precision applications. Moreover, the float glass process struggles to precisely control the microstructure and properties of the glass, limiting its application in producing ultra-thin glass requiring specific electrical or optical properties.

[0005] 2. Drop-down method:

[0006] The down-drawing method includes vertical down-drawing and horizontal down-drawing. In the vertical down-drawing method, molten glass flows out from the top slot and is drawn vertically downwards under gravity and traction to form a glass ribbon. In the horizontal down-drawing method, the molten glass is drawn horizontally. Although these methods can produce ultra-thin glass of a certain thickness, they still have shortcomings in terms of production efficiency and product quality. During the down-drawing process, the cooling rate of the glass ribbon is difficult to control precisely, which can easily generate internal stress, leading to a decrease in the strength and stability of the glass. At the same time, the complexity of the equipment and the high maintenance cost limit its large-scale application. For example, when preparing ultra-thin glass with a thickness of 0.3 mm, the strength of glass produced by the down-drawing method may be 20%-30% lower than that of glass prepared by an optimized process, and the surface flatness deviation is larger, which will affect light propagation and imaging quality in optical applications.

[0007] The shortcomings of existing ultrathin flexible glass in applications are as follows:

[0008] 1. Electronic equipment field:

[0009] In flexible display applications, while existing ultra-thin flexible glass can achieve a certain degree of bending, its fatigue resistance is insufficient during long-term folding. After repeated folding, microcracks will form inside the glass and gradually expand, leading to deterioration of display quality or even screen failure. For example, some existing flexible displays develop noticeable bright lines or black spots after 10,000 folds, due to damage to the internal structure of the ultra-thin flexible glass. Moreover, in touchscreen applications, it is difficult to optimize the balance between conductivity and touch sensitivity of existing ultra-thin flexible glass. Either insufficient conductivity leads to delayed touch response, or the glass's flexibility or light transmittance is sacrificed to improve conductivity.

[0010] 2. Optical Devices Field:

[0011] For optical devices such as optical sensors, existing ultrathin flexible glass lacks precision in refractive index control. Due to non-uniform refractive index, scattering and chromatic aberration occur during light signal transmission, reducing the sensor's detection accuracy. For example, some high-precision optical sensors require a refractive index deviation within ±0.001, but existing ultrathin flexible glass struggles to meet this requirement, leading to increased measurement errors. Furthermore, in optical coating applications, existing ultrathin flexible glass suffers from poor coating adhesion and uniformity due to surface quality and uniformity issues, affecting the optical performance and lifespan of the coating.

[0012] In summary, existing technologies have many defects and shortcomings in the preparation and application of ultrathin flexible glass, making it difficult to meet the urgent needs of current and future high-tech fields for high-performance, multifunctional, high-quality, and low-cost large-scale production of ultrathin flexible glass. Therefore, developing a new method for fabricating ultrathin flexible glass using magnetron sputtering is of great significance. Summary of the Invention

[0013] To address the aforementioned technical problems, this invention proposes a method for manufacturing ultrathin flexible glass.

[0014] To achieve the above objectives, the present invention provides the following technical solution:

[0015] A method for manufacturing ultrathin flexible glass includes the following steps:

[0016] Using a metal sheet as a substrate and silicon dioxide as a target, magnetron sputtering is performed to obtain a metal sheet with a silicon dioxide film after the magnetron sputtering is completed. The metal sheet with the silicon dioxide film is then immersed in an acid solution to remove the metal sheet, resulting in an ultrathin flexible glass film suspended in the acid solution. The ultrathin flexible glass film is then cleaned and dried to obtain the ultrathin flexible glass.

[0017] The thickness of the ultrathin flexible glass is 10nm to 500nm, and the thickness is uniform with a thickness uniformity deviation of ±1nm to ±2nm.

[0018] Furthermore, prior to magnetron sputtering, the process includes a pretreatment step of cleaning and drying the metal sheet. The method for cleaning and drying the metal sheet is not limited in this invention; any method that effectively removes oil and impurities from the surface of the metal sheet is acceptable.

[0019] The metal sheet has a thickness of 0.5 mm to 1 mm, a width of 60 mm, a length of 80 mm, and a surface roughness (Ra) of less than 0.3 nm.

[0020] In the method of this invention, the substrate only needs to be etched away by an acid solution. For example, the metal sheet is an aluminum sheet or a copper sheet.

[0021] The silicon dioxide has a diameter of 50 mm and a thickness of 4 mm.

[0022] During magnetron sputtering, the working gas is argon, with a pressure of 0.05–0.6 Pa, a sputtering power of 80–600 W, a substrate temperature of 40–220 °C, a sputtering rate of 0.08–1.2 nm / s, and a sputtering time of 20–40 min. Lower working pressure (i.e., higher pressure) helps to obtain denser films, but the deposition rate is lower. Higher pressure increases plasma density and deposition rate, but may lead to voids in the film. Therefore, optimizing the gas pressure can balance the density of the film and the deposition rate. Sputtering power has a significant impact on the film growth rate and quality. With increasing sputtering power, the deposition rate increases linearly, but beyond a certain power, the limited power tolerance of the target may cause a decrease in the insulation performance between the target and the shield, leading to arcing, which affects the quality and uniformity of the film. Substrate temperature affects the crystallinity and density of thin films. Higher temperatures increase crystallinity and density, which is beneficial for improving device performance; while lower temperatures are suitable for the deposition of thermistor materials and amorphous thin films. Therefore, selecting an appropriate substrate temperature can control the microstructure of the thin film. The deposition rate affects the migration time of sputtered atoms on the substrate surface, thus indirectly affecting factors such as the number of nuclei, internal stress, surface roughness, and internal defects. Low deposition rates may lead to rough and non-dense film surfaces, while high deposition rates may lead to excessive internal stress and increased defects. Sputtering time directly determines the film thickness. With other conditions such as sputtering power and operating pressure remaining constant, increasing the sputtering time leads to an increase in film thickness. By controlling the sputtering time, films of different thicknesses can be obtained. This invention allows for the adjustment of the thickness of ultrathin flexible glass by controlling the parameters of magnetron sputtering.

[0023] Preferably, during magnetron sputtering, the working gas is argon, the pressure is 0.25 Pa, the sputtering power is 150 W, the substrate temperature is 100 °C, the sputtering rate is 0.05 nm / s, and the sputtering time is 30 min. Under these magnetron sputtering conditions, ultrathin flexible glass with a thickness of 20 nm and a thickness uniformity deviation within ±1 nm can be obtained.

[0024] Furthermore, the argon flow rate is 15–60 sccm, preferably 40 sccm.

[0025] When immersing the metal sheet with the silicon dioxide film in hydrochloric acid solution, the temperature is 18-32°C and the time is 20-24 hours.

[0026] In this invention, the mass concentration of the acid solution is 6%. Immersing a metal sheet with a silica film in the acid solution etches away the metal, resulting in an ultrathin flexible glass film. Exemplarily, the acid solution is a hydrochloric acid solution or a dilute nitric acid solution.

[0027] Furthermore, after obtaining the ultrathin flexible glass film, the process includes quality inspection steps, such as using an optical microscope to inspect the flatness of the ultrathin glass film surface, using an atomic force microscope to inspect the surface roughness, and using a spectrometer to inspect the optical properties. If the test results do not meet the preset standards, the magnetron sputtering step or the weak acid treatment (i.e., hydrochloric acid solution immersion) step is repeated, and the corresponding parameters are adjusted.

[0028] The cleaning process involves rinsing the ultra-thin flexible glass film with deionized water for at least 8 minutes. Further, the rinsing time with deionized water is 8–10 minutes. This cleaning removes residual hydrochloric acid solution and other impurities from the surface of the ultra-thin flexible glass film, further improving its cleanliness.

[0029] This invention does not limit the drying method, as long as the drying effect is achieved. For example, the drying is vacuum drying, with a temperature of 35-65°C, a vacuum degree of 0.04-0.12 MPa, and a time of 25-70 minutes.

[0030] For example, the method for manufacturing the ultrathin flexible glass is as follows:

[0031] 1. Raw material preparation:

[0032] Aluminum sheets with a purity of 99.9% were selected as the substrate material. The sheets were 1 mm thick, 60 mm wide, and 80 mm long, with a surface roughness (Ra) of less than 0.3 nm. The aluminum sheets were pre-cleaned and dried to remove surface oil and impurities. The sputtering target was a silicon dioxide target with a purity of 99.99%, a diameter of 50 mm, and a thickness of 4 mm, ensuring sufficient material supply and uniform, stable composition during sputtering.

[0033] 2. Pretreatment for magnetron sputtering equipment:

[0034] Place the aluminum substrate flat on the sample holder inside the vacuum chamber of the magnetron sputtering equipment, ensuring the aluminum substrate is completely fixed and horizontal to prevent curling or displacement during sputtering. After closing the chamber door, start the high vacuum pump system to evacuate the chamber to a vacuum level of 1×10⁻⁶. -5 The pressure is below 100 Pa to remove impurities, water vapor, and other contaminants that may affect the film quality from the chamber, creating an extremely pure environment for the sputtering process.

[0035] 3. Sputtering gas and process parameter settings:

[0036] Argon gas was introduced at a flow rate of 40 sccm, and the flow rate was precisely controlled by a high-precision mass flow controller to maintain the pressure in the chamber at 0.25 Pa. The sputtering power was set to 150 W, and the target-substrate distance was adjusted to 60 mm. The magnetic field structure of the magnetron sputtering device was optimized to ensure uniform plasma distribution on the surface of the silica target, thereby ensuring that the sputtered silica atoms could be uniformly deposited on the aluminum substrate.

[0037] 4. Sputter deposition process:

[0038] The magnetron sputtering apparatus was turned on to begin depositing an ultrathin flexible glass film on an aluminum substrate. The sputtering rate was set to 0.05 nm / s, and the deposition time (i.e., sputtering time, hereinafter the same) was set to 30 min. During the deposition process, the sample holder rotated slowly at 2 rpm, while the temperature of the aluminum substrate was stabilized at approximately 100°C using a temperature control system within the chamber. This temperature control helps improve the density and uniformity of the film, reducing internal stress and defects. Furthermore, a real-time monitoring system was employed during sputtering, using optical sensors to monitor changes in film thickness and refractive index, allowing for timely adjustments to process parameters and ensuring the stability and consistency of film quality.

[0039] 5. Aluminum substrate dissolution and separation from ultrathin flexible glass:

[0040] After sputtering, the aluminum sheet with the silica film is removed from the magnetron sputtering equipment and placed in a container filled with a 6% (w / w) weak hydrochloric acid solution. The container is equipped with a stirrer to ensure uniform contact between the solution and the aluminum sheet, accelerating the dissolution process. At a temperature of 25±2℃, the aluminum sheet gradually dissolves in the weak hydrochloric acid solution. After 20 hours, the aluminum foil is completely dissolved, yielding an ultrathin flexible glass film suspended in the solution.

[0041] 6. Post-processing:

[0042] The ultrathin flexible glass film was separated from the solution using a filtration device, and then repeatedly rinsed with deionized water for 10 minutes to remove residual weak hydrochloric acid and other impurities from the surface. The cleaned ultrathin flexible glass film was then placed in a drying oven and dried at 55℃ and 0.08MPa vacuum for 30 minutes to obtain ultrathin flexible glass. Performance tests were performed on the dried ultrathin flexible glass. Using atomic force microscopy, the thickness of the ultrathin flexible glass was measured to be 20nm, with a thickness uniformity deviation within ±1nm, a surface roughness of 0.2nm, and an average transmittance of not less than 95% in the visible light range. Its sheet resistance was measured to be 20Ω / □ using the four-point probe method. After 100,000 repeated bending tests, the film showed no obvious cracks or damage, and the average transmittance in the visible light range remained above 90%.

[0043] This invention can successfully produce ultra-thin flexible glass that meets the requirements of flexible touch panels. The ultra-thin flexible glass of this invention can be used as a key material for flexible touch panels, realizing highly flexible and thin designs of touch panels, improving the user's touch operation experience and expanding product application scenarios, such as foldable mobile phones, tablets, smartwatches and other flexible touch devices.

[0044] The present invention also provides an ultrathin flexible glass produced by the above method, which has a surface roughness of less than 10 nm and an average transmittance of not less than 95% in the visible light range.

[0045] The present invention also provides the application of the ultrathin flexible glass in electronic display devices, optical instruments or optical communication devices.

[0046] Compared with the prior art, the present invention has the following advantages and technical effects:

[0047] 1. By optimizing the process parameters of magnetron sputtering, this invention can precisely prepare ultrathin flexible glass with a thickness of up to 20 nm, meeting the stringent requirements of modern technology for ultrathin glass. After 100,000 repeated bending tests, there were no obvious cracks or damage, proving that this invention has successfully prepared ultrathin flexible glass.

[0048] 2. This invention utilizes magnetron sputtering to deposit various functional thin films on the glass surface, enabling ultrathin glass to possess excellent electrical and optical properties, such as high conductivity and precisely controllable refractive index, greatly expanding the application range of ultrathin glass.

[0049] 3. The ultrathin flexible glass prepared by this invention has good uniformity and stability. After rigorous performance testing, its thickness uniformity deviation is within ±1nm to ±2nm. Its performance degradation is minimal during long-term use. It can adapt to complex and ever-changing usage environments and has extremely high reliability and durability. Attached Figure Description

[0050] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0051] Figure 1 The images shown are actual pictures of the silica target material of the present invention, wherein the left image is a front view of the silica target material with a purity of 99.99%, and the right image is a back view of the silica target material with a purity of 99.99%.

[0052] Figure 2 This is a schematic diagram of the main components of the magnetron sputtering device using an aluminum sheet as a substrate according to the present invention, and a schematic diagram of the manufacturing method of the present invention.

[0053] Figure 3 This is a schematic diagram of the structure of the ultrathin flexible glass prepared in Example 1. Detailed Implementation

[0054] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0055] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0056] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0057] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0058] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0059] Ultra-thin flexible glass (UTG) is a type of glass material with flexibility and bendability, less than 100 micrometers thick. Unlike traditional rigid glass, it can be bent arbitrarily under external force without heat treatment. This material is made through a special manufacturing process and has characteristics such as ultra-thinness, wear resistance, high temperature resistance, corrosion resistance, high strength, high light transmittance, bendability, and good resilience.

[0060] Unless otherwise specified, the room temperature in this invention is 25±2℃.

[0061] In the embodiments of the present invention, the method for cleaning and drying the aluminum sheet is not limited, as long as it can achieve the effect of removing oil and impurities from the surface of the aluminum sheet.

[0062] In embodiments of the present invention, an atomic force microscope is used to detect surface roughness, a spectrometer is used to detect the optical properties of the ultrathin flexible glass, and an optical microscope is used to detect the flatness of the ultrathin flexible glass surface.

[0063] All raw materials used in the embodiments of this invention were obtained through commercial purchase.

[0064] In an embodiment of the present invention, a method for manufacturing ultrathin flexible glass is provided, comprising the following steps:

[0065] Using a metal sheet as a substrate and silicon dioxide as a target, magnetron sputtering is performed. After magnetron sputtering, a metal sheet with a silicon dioxide film is obtained. The metal sheet with the silicon dioxide film is immersed in an acid solution to remove the metal sheet, resulting in an ultrathin flexible glass film suspended in the acid solution. The ultrathin flexible glass film is then cleaned and dried to obtain ultrathin flexible glass.

[0066] The ultrathin flexible glass has a thickness of 10nm to 500nm, and the thickness is uniform with a thickness uniformity deviation of ±1nm to ±2nm. The surface roughness is less than 10nm, and the average transmittance in the visible light range is not less than 95%. Preferably, the thickness of the ultrathin flexible glass is 20nm to 100nm; more preferably, the thickness of the ultrathin flexible glass is 20nm, and the thickness is uniform with a thickness uniformity deviation within ±1nm.

[0067] In some embodiments of the present invention, a pretreatment step of cleaning and drying the metal sheet is included before magnetron sputtering. The method for cleaning and drying the metal sheet is not limited in the present invention, as long as it achieves the effect of removing oil and impurities from the surface of the metal sheet.

[0068] In some embodiments of the present invention, the metal sheet has a thickness of 0.5 mm to 1 mm, a width of 60 mm, a length of 80 mm, and a surface roughness (Ra) of less than 0.3 nm. The substrate only needs to be etchable by an acid solution. In the following typical embodiments of the present invention, aluminum or copper sheets are used for illustration.

[0069] In some embodiments of the present invention, the silicon dioxide has a diameter of 50 mm and a thickness of 4 mm.

[0070] In some embodiments of the present invention, during magnetron sputtering, the working gas is argon, the pressure is 0.05–0.6 Pa, the sputtering power is 80–600 W, the substrate temperature is 40–220 °C, the sputtering rate is 0.08–1.2 nm / s, and the sputtering time is 20–40 min. By controlling the parameters of magnetron sputtering, the thickness of the ultrathin flexible glass can be adjusted. Preferably, during magnetron sputtering, the working gas is argon, the pressure is 0.25 Pa, the sputtering power is 150 W, the substrate temperature is 100 °C, the sputtering rate is 0.05 nm / s, and the sputtering time is 30 min. Under these magnetron sputtering conditions, an ultrathin flexible glass with a thickness of 20 nm and a thickness uniformity deviation within ±1 nm can be obtained.

[0071] In some embodiments of the present invention, the argon flow rate is 15 to 60 sccm, preferably 40 sccm.

[0072] In some embodiments of the present invention, when immersing aluminum sheets with a silicon dioxide film in an acid solution, the temperature is 18–32°C and the time is 20–24 hours.

[0073] In some embodiments of the present invention, the mass concentration of the acid solution is 6%. Immersion in the acid solution is to remove metal ions and obtain a pure, ultrathin, flexible glass film. The acid solution is a hydrochloric acid solution or a dilute nitric acid solution. For example, immersing an aluminum sheet with a silica film in a hydrochloric acid solution can etch away the aluminum, resulting in an ultrathin, flexible glass film.

[0074] In some embodiments of the present invention, after obtaining the ultrathin flexible glass film, a quality inspection step is included, in which the flatness of the surface of the ultrathin glass film is detected using an optical microscope, the surface roughness is detected using an atomic force microscope, and the optical performance is detected using a spectrometer. If the test results do not meet the preset standards, the magnetron sputtering step or the weak acid treatment (i.e., hydrochloric acid solution immersion) step is repeated, and the corresponding parameters are adjusted.

[0075] In some embodiments of the present invention, cleaning involves rinsing the ultrathin flexible glass film with deionized water for at least 8 minutes. Further, the rinsing time with deionized water is 8-10 minutes. Cleaning can remove residual hydrochloric acid solution and other impurities from the surface of the ultrathin flexible glass film, further improving the cleanliness of the ultrathin flexible glass.

[0076] In some embodiments of the present invention, the drying method is not limited, as long as the drying effect is achieved. For example, the drying is vacuum drying, with a temperature of 35-65°C, a vacuum degree of 0.04-0.12 MPa, and a time of 25-70 min.

[0077] A physical image of the silica target material of this invention is shown below. Figure 1 The left image shows the front view of a silica target with a purity of 99.99%, and the right image shows the back view of a silica target with a purity of 99.99%.

[0078] The structural schematic diagram of the main components of the magnetron sputtering device using an aluminum sheet as a substrate, and the schematic diagram of the manufacturing method of the present invention, are shown below. Figure 2 The main components of the magnetron sputtering apparatus are showcased. The main body of the apparatus is a sealed vacuum chamber. A 1mm thick aluminum sheet with a purity of at least 99.9% is mounted on the top of the chamber and connected to the anode end. A 4mm thick, 50mm diameter silica target with a purity of 99.99% is mounted on the bottom of the chamber. The target is connected to the cathode end via wires to provide the energy required for sputtering. An inlet pipe is connected to the side of the chamber for precise control of the flow rate and proportion of the sputtering gas argon. A vacuum pump at the bottom of the chamber can evacuate the air pressure to an extremely low level, creating a suitable vacuum environment for sputtering. Furthermore, a magnetic field generator is installed within the chamber, surrounding the target, to confine the plasma by generating a specifically distributed magnetic field, thereby improving sputtering efficiency and thin film quality.

[0079] This invention has achieved at least the following advancements:

[0080] I. Overcoming the bottleneck in the preparation of ultrathin flexible glass

[0081] By precisely controlling thickness and uniformity, and through in-depth exploration and innovative optimization of magnetron sputtering process parameters, ultra-precise control over the thickness of ultrathin flexible glass has been achieved. The aim is to stably fabricate ultrathin flexible glass with a thickness ranging from 10nm to 500nm and a thickness uniformity deviation strictly controlled within ±1nm to ±2nm. This achievement will strongly meet the stringent requirements for glass thickness consistency in cutting-edge applications such as ultra-high resolution flexible displays and ultra-precision optical sensors, laying a solid foundation for performance advancements in these high-end products.

[0082] II. Expanding the Diverse Applications of Ultra-thin Flexible Glass

[0083] Leading the flexible revolution in electronic devices, we tailor high-performance, ultra-thin flexible glass substrates for next-generation flexible electronic devices. In flexible display applications, we ensure that the glass substrates possess both ultra-high visible light transmittance (>90%) and extremely low sheet resistance (<30Ω / □) to achieve superior electrical performance and excellent display effects.

[0084] III. Achieving Efficient Fabrication of Ultrathin Flexible Glass

[0085] This study comprehensively and systematically investigates all aspects of magnetron sputtering technology in the fabrication of ultrathin flexible glass. Utilizing advanced experimental design methods and numerical simulation techniques, it deeply analyzes the complex interactions between process parameters and constructs an intelligent and precise process parameter optimization model. This model enables the rapid and accurate determination of the optimal combination of process parameters, significantly shortening the R&D cycle of the fabrication process (by more than 50% compared to traditional methods) and substantially improving production efficiency and product quality stability. Simultaneously, through process innovation and equipment improvement, it achieves continuous and automated production of ultrathin flexible glass, further enhancing production efficiency and reducing production costs, laying a solid foundation for the large-scale industrial production of ultrathin flexible glass.

[0086] In summary, this invention aims to comprehensively improve the preparation technology and application value of ultrathin flexible glass through in-depth innovation and application expansion of magnetron sputtering technology, providing strong material support and technical guarantee for the rapid development of modern science and technology industries, and leading the transformative application and sustainable development trend of ultrathin flexible glass in multiple fields.

[0087] It should be noted that all aspects not described in detail in this invention are conventional operating methods in the field and are not the focus of this invention. For example, the specific methods for cleaning and drying aluminum sheets are all completed using conventional methods.

[0088] The technical solution of the present invention will be further illustrated by the following embodiments.

[0089] Example 1: Preparation of ultrathin flexible glass for flexible touch panels

[0090] 1. Raw material preparation:

[0091] Aluminum sheets with a purity of 99.9% were selected as the substrate material. The sheets were 1 mm thick, 60 mm wide, and 80 mm long, with a surface roughness (Ra) of less than 0.3 nm. The aluminum sheets were pre-cleaned and dried to remove surface oil and impurities. The sputtering target was a silicon dioxide target with a purity of 99.99%, a diameter of 50 mm, and a thickness of 4 mm, ensuring sufficient material supply and uniform, stable composition during sputtering.

[0092] 2. Pretreatment for magnetron sputtering equipment:

[0093] Place the aluminum substrate flat on the sample holder inside the vacuum chamber of the magnetron sputtering equipment, ensuring the aluminum substrate is completely fixed and horizontal to prevent curling or displacement during sputtering. After closing the chamber door, start the high vacuum pump system to evacuate the chamber to a vacuum level of 1×10⁻⁶. -5 The pressure is below 100 Pa to remove impurities, water vapor, and other contaminants that may affect the film quality from the chamber, creating an extremely pure environment for the sputtering process.

[0094] 3. Sputtering gas and process parameter settings:

[0095] Argon gas was introduced at a flow rate of 40 sccm, and the flow rate was precisely controlled by a high-precision mass flow controller to maintain the pressure in the chamber at 0.25 Pa. The sputtering power was set to 150 W, and the target-substrate distance was adjusted to 60 mm. The magnetic field structure of the magnetron sputtering device was optimized to ensure uniform plasma distribution on the surface of the silica target, thereby ensuring that the sputtered silica atoms could be uniformly deposited on the aluminum substrate.

[0096] 4. Sputter deposition process:

[0097] The magnetron sputtering apparatus was turned on to begin depositing an ultrathin flexible glass film on an aluminum substrate. The sputtering rate was set to 0.05 nm / s, and the deposition time was set to 30 min. During deposition, the sample holder rotated slowly at 2 rpm, while the temperature of the aluminum substrate was stabilized at 100 ± 1 °C using a temperature control system within the chamber. This temperature control helps improve the density and uniformity of the film, reducing internal stress and defects. Furthermore, a real-time monitoring system was employed during sputtering, using optical sensors to monitor changes in film thickness and refractive index, allowing for timely adjustments to process parameters and ensuring the stability and consistency of film quality.

[0098] 5. Aluminum substrate dissolution and separation from ultrathin flexible glass:

[0099] After sputtering, the aluminum sheet with the silica film is removed from the magnetron sputtering equipment and placed in a container containing 1L of a 6% (w / w) weak hydrochloric acid solution. The container is equipped with a stirrer to ensure uniform contact between the solution and the aluminum sheet, accelerating the dissolution process. At a temperature of 25±2℃, the aluminum sheet gradually dissolves in the weak hydrochloric acid solution. After 20 hours, the aluminum foil is completely dissolved, yielding an ultrathin flexible glass film suspended in the solution.

[0100] 6. Post-processing:

[0101] The ultrathin flexible glass film was separated from the solution using a filtration device, and then repeatedly rinsed with deionized water for 10 minutes to remove residual weak hydrochloric acid and other impurities from the surface. Next, the cleaned ultrathin flexible glass film was placed in a drying oven and dried at 55°C and 0.08 MPa vacuum for 30 minutes to obtain ultrathin flexible glass. A schematic diagram of the structure of the ultrathin flexible glass (hereinafter referred to as "ultrathin glass") prepared in this embodiment is shown below. Figure 3 Performance tests were conducted on the dried ultrathin flexible glass. Using atomic force microscopy, the thickness of the ultrathin flexible glass was measured to be 20 nm, with uniform thickness and a thickness uniformity deviation within ±1 nm. The Ra value was 0.2 nm, and the average transmittance in the visible light range was not less than 98%. The sheet resistance was measured to be 20 Ω / □ using the four-point probe method. Flexibility testing was conducted according to GB / T 38686-2020 "Test Method for Flexibility of Ultrathin Glass - Two-Point Bending Method". After 100,000 repeated bending tests, the ultrathin flexible glass showed no obvious cracks or damage. The highest transmittance in the visible light range was 95%, and the average transmittance in the visible light range remained above 90%. This fully meets the requirements for ultrathin flexible glass in flexible touch panels and can be used as a key material for flexible touch panels, enabling highly flexible and thin designs, improving the user's touch operation experience, and expanding product application scenarios. For example, it can be applied to flexible touch devices such as foldable phones, tablets, and smartwatches.

[0102] Example 2

[0103] Same as Example 1, except that in step 1, a copper sheet with a purity of 99.9% is used as the substrate material, with a thickness of 1 mm, a width of 60 mm, a length of 80 mm, a surface roughness (Ra) of 0.3 nm, an argon flow rate of 50 sccm, a chamber pressure of 0.6 Pa, and a sputtering power of 300 W; in step 5, 1 L of a 6% dilute nitric acid solution is used to dissolve the copper substrate and separate it from the ultrathin flexible glass, the deposition time is set to 20 min, and the substrate temperature is 240 °C.

[0104] The ultrathin flexible glass obtained in this embodiment has a thickness of 80 nm, uniform thickness with a thickness uniformity deviation within ±1 nm, an Ra of 1.5 nm, and an average transmittance of not less than 95% in the visible light range. Its sheet resistance, measured using the four-point probe method, is 15 Ω / □. Flexibility testing was conducted according to GB / T 38686-2020 "Test Method for Flexibility of Ultrathin Glass - Two-Point Bending Method". After 100,000 repeated bending tests, the ultrathin flexible glass showed no obvious cracks or damage, and its average transmittance in the visible light range remained above 90%.

[0105] Example 3

[0106] Same as Example 1, except that the thickness of the aluminum substrate in step 1 is changed to 0.5 mm; in step 4, the sputtering rate is set to 0.08 nm / s, the deposition time is set to 0 min, and the substrate temperature is 140 °C.

[0107] The ultrathin flexible glass obtained in this embodiment has a thickness of 50 nm, uniform thickness with a thickness uniformity deviation within ±2 nm, an Ra of 1.5 nm, and an average transmittance of not less than 95% in the visible light range. Its sheet resistance, measured using the four-point probe method, is 18 Ω / □. Flexibility testing was conducted according to GB / T 38686-2020 "Test Method for Flexibility of Ultrathin Glass - Two-Point Bending Method". After 100,000 repeated bending tests, the ultrathin flexible glass showed no obvious cracks or damage, and its average transmittance in the visible light range remained above 90%.

[0108] Example 4

[0109] Same as Example 1, except that the deposition time in step 4 is set to 20 min.

[0110] The ultrathin flexible glass obtained in this embodiment has a thickness of 10 nm, uniform thickness with a thickness uniformity deviation within ±1 nm, an Ra value of 0.1 nm, and an average transmittance of not less than 95% in the visible light range. Its sheet resistance, measured using the four-point probe method, is 25 Ω / □. Flexibility testing was conducted according to GB / T 38686-2020 "Test Method for Flexibility of Ultrathin Glass - Two-Point Bending Method". After 100,000 repeated bending tests, the ultrathin flexible glass showed no obvious cracks or damage, and its average transmittance in the visible light range remained above 90%.

[0111] Example 5

[0112] Same as Example 1, except that the deposition time in step 4 is set to 40 min.

[0113] The ultrathin flexible glass obtained in this embodiment has a thickness of 60 nm, uniform thickness with a thickness uniformity deviation within ±1 nm, an Ra of 1.5 nm, and an average transmittance of not less than 95% in the visible light range. Its sheet resistance, measured using the four-point probe method, is 16 Ω / □. Flexibility testing was conducted according to GB / T 38686-2020 "Test Method for Flexibility of Ultrathin Glass - Two-Point Bending Method". After 100,000 repeated bending tests, the ultrathin flexible glass showed no obvious cracks or damage, and its average transmittance in the visible light range remained above 90%.

[0114] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for manufacturing ultrathin flexible glass, characterized in that, Includes the following steps: Using a metal sheet as a substrate and silicon dioxide as a target, magnetron sputtering is performed to obtain a metal sheet with a silicon dioxide film after the magnetron sputtering is completed. The metal sheet with the silicon dioxide film is then immersed in an acid solution to remove the metal sheet, resulting in an ultrathin flexible glass film suspended in the acid solution. The ultrathin flexible glass film is then cleaned and dried to obtain the ultrathin flexible glass. The thickness of the ultrathin flexible glass is 10nm to 500nm, and the thickness uniformity deviation is ±1nm to ±2nm.

2. The method for manufacturing ultrathin flexible glass according to claim 1, characterized in that, Before magnetron sputtering, the process also includes a pretreatment step of cleaning and drying the metal sheet.

3. The method for manufacturing ultrathin flexible glass according to claim 2, characterized in that, The metal sheet has a thickness of 0.5 mm to 1 mm, a width of 60 mm, a length of 80 mm, and a surface roughness of less than 0.3 nm.

4. The method for manufacturing ultrathin flexible glass according to claim 1, characterized in that, The silicon dioxide has a diameter of 50 mm and a thickness of 4 mm.

5. The method for manufacturing ultrathin flexible glass according to claim 1, characterized in that, During magnetron sputtering, the working gas is argon, the pressure is 0.05–0.6 Pa, the sputtering power is 80–600 W, the substrate temperature is 40–220 °C, the sputtering rate is 0.08–1.2 nm / s, and the sputtering time is 20–40 min.

6. The method for manufacturing ultrathin flexible glass according to claim 5, characterized in that, During magnetron sputtering, the working gas is argon, the pressure is 0.25 Pa, the sputtering power is 150 W, the substrate temperature is 100 °C, the sputtering rate is 0.05 nm / s, and the sputtering time is 30 min.

7. The method for manufacturing ultrathin flexible glass according to claim 5, characterized in that, The argon flow rate is 15–60 sccm.

8. The method for manufacturing ultrathin flexible glass according to claim 1, characterized in that, When immersing the metal sheet with the silicon dioxide film in hydrochloric acid solution, the temperature is 18-32°C and the time is 20-24 hours.

9. An ultrathin flexible glass, characterized in that, The ultrathin flexible glass, manufactured according to any one of claims 1 to 8, has a surface roughness of less than 10 nm and an average transmittance of not less than 95% in the visible light range.

10. The application of the ultrathin flexible glass according to claim 9 in electronic display devices, optical instruments or optical communication devices.

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