Diamond film glass substrate preparation device and method based on laser deposition

Abstract

The invention provides a diamond film glass substrate preparation device and method based on laser deposition, and belongs to the field of laser deposition. A glass material is selected to prepare a substrate, and a diamond film precursor gas mixture is configured; the substrate is arranged in a vacuum environment, the prepared diamond film precursor gas mixture is conveyed into the vacuum environment, laser deposition is carried out on the surface of the substrate, and the substrate is evenly covered with a diamond film; and carrying out annealing and surface characteristic detection on the diamond film deposited on the substrate. According to the method, the accurately configured precursor gas mixture is adopted to assist laser deposition in the vacuum environment, impurities and defects are reduced, the growth process of the diamond film is optimized by controlling laser parameters and environmental conditions, and the thermal expansion and stability of the substrate are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of laser deposition, and in particular to a device and method for preparing a diamond film glass substrate based on laser deposition. Background Art

[0002] With the rapid development of electronic technology, the application of traditional silicon substrates in high-performance chip manufacturing has gradually faced many challenges. In recent years, glass substrates have gradually become a new choice to replace silicon substrates due to their superior optical properties, thermal stability and lightweight advantages. However, the thermal expansion and electrical conductivity of glass substrates in electronic devices still need to be improved.

[0003] Laser deposition technology, as an emerging thin film preparation method, has been widely used in the semiconductor and optoelectronic fields by depositing high-quality functional thin films on the substrate surface. In this process, the laser beam irradiates the substrate surface with high energy density, vaporizing or melting the material and redepositing it to form the desired thin film.

[0004] Although the existing technology has achieved the deposition of various thin films on glass substrates, the selection and control of laser parameters are still particularly important in the deposition process of diamond films. In the existing technology, laser parameters such as laser power, pulse frequency and beam focus position are often regarded as fixed values, which may lead to uncertainty in the quality and uniformity of the film during the deposition process. For example, changes in laser power directly affect the growth rate and structural characteristics of the diamond film, while the laser pulse frequency affects the deposition thickness and density of the film. Summary of the invention

[0005] In view of this, the present invention proposes a device and method for preparing a diamond film glass substrate based on laser deposition, which is used to solve the problem of how to improve the quality of the diamond film layer and the performance of the substrate by accurately controlling the precursor gas flow rate and laser parameters.

[0006] The technical solution of the present invention is implemented as follows: The present invention provides a method for preparing a diamond film glass substrate based on laser deposition, comprising the following steps:

[0007] S1, selecting a glass material to prepare a substrate and preparing a diamond film precursor gas mixture;

[0008] S2, placing the substrate in a vacuum environment, delivering a configured diamond film precursor gas mixture into the vacuum environment, and performing laser deposition on the surface of the substrate so that the substrate is evenly covered with a diamond film;

[0009] S3, annealing and surface property testing of the diamond film deposited on the substrate.

[0010] On the basis of the above technical solution, preferably, in step S1, methane and hydrogen are selected as precursor gases, and the mixing ratio of methane and hydrogen is set according to deposition conditions and expected film properties.

[0011] More preferably, in step S2, when the diamond film precursor gas mixture is transported into the vacuum environment where the substrate is located, a gas flow prediction model based on machine learning is introduced. By learning from previous experimental data, the changing trend of the gas flow of methane and hydrogen is predicted and dynamically adjusted to provide an ideal precursor gas environment for laser deposition of diamond film on the substrate surface, so as to avoid sudden gas flow fluctuations affecting the deposition effect.

[0012] More preferably, the prediction model of the gas flow rate change trend of methane and hydrogen is,

[0013]

[0014] Where t is time, and are the predicted flow rates of methane and hydrogen at the next time step at time t, respectively. X(t) is the input feature matrix of the model. The input features of the model include the historical gas flow data, environmental conditions and equipment parameters of methane and hydrogen. t-1 is the hidden state at time t-1, and θ is the trainable parameter of the model;

[0015] The adjustment formulas for dynamically adjusting the gas flow rates of methane and hydrogen are:

[0016]

[0017] in, and are the gas flow rates of methane and hydrogen adjusted for the next time step, and is the gas flow rate of methane and hydrogen in the current time step, α is the adjustment coefficient and is used to smooth the change of gas flow rate, and the value range of α is between 0 and 1.

[0018] On the basis of the above technical solution, preferably, in step S2, the deposition rate of the diamond film on the substrate is adjusted by adjusting the laser power and the pulse frequency. The calculation formula of the deposition rate is:

[0019] R=(f×A) / D,

[0020] Where R is the deposition rate, f is the pulse frequency, A is the thickness of the material deposited per pulse, and A is the effective area of ​​the substrate.

[0021] More preferably, in step S2, the deposition rate and the deposition thickness of the diamond film are monitored during the laser deposition process, and an adaptive frequency adjustment algorithm based on machine learning is introduced to optimize the pulse frequency. The adjustment algorithm formula is:

[0022] f new =f old +β×(R target -R measured ),

[0023] Among them, β is the pulse frequency adjustment coefficient, R target is the target deposition rate, R measured The deposition rate is monitored in real time. The optimal frequency control under different film thicknesses is achieved through adaptive adjustment.

[0024] On the basis of the above technical solution, preferably, in step S2, the focus of the laser is adjusted to focus the laser on the surface of the glass substrate, and the calculation formula of the spot diameter D of the laser focus is:

[0025] D = (2 × λ ​​× F) / (π × D0),

[0026] Wherein, λ is the laser wavelength, F is the focal length of the focusing lens, F ranges from 50 mm to 100 mm, D0 is the input diameter of the laser beam, and D ranges from 50 μm to 200 μm.

[0027] On the basis of the above technical solution, preferably, in step S3, the diamond film is annealed by a segmented annealing method, and the temperature distribution formula during annealing can be expressed as:

[0028] T(t)=T0+ΔT×sin(πt / t f ),

[0029] Where T0 is the initial temperature, ΔT is the temperature variation range, t is the deposition time, and t f is the end time of the annealing process.

[0030] On the basis of the above technical solution, preferably, in step S3, when detecting the surface characteristics of the diamond film, an ellipsometer or a step meter is used to measure the thickness of the diamond film, and confirm whether the thickness of the diamond film meets the design requirements; and the uniformity of the film layer is evaluated by detecting multiple positions of the diamond film, and the tolerance range of the film thickness is ±10%.

[0031] On the other hand, the present invention provides a device for preparing a diamond film glass substrate based on laser deposition, which is used for the above-mentioned method for preparing a diamond film glass substrate based on laser deposition, including a vacuum chamber in which a substrate is arranged; a laser device, which emits laser into the vacuum chamber and is used to laser deposit a diamond film on the surface of the substrate; a gas delivery system, which delivers a configured diamond film precursor gas mixture into the vacuum chamber; a control unit, which is electrically connected to the vacuum chamber, the laser device and the gas delivery system, the control unit monitors and adjusts the power, pulse frequency and focal position of the laser device in real time, the control unit adjusts the flow rate and proportion of the diamond film precursor gas mixture delivered by the gas delivery system, and the control unit monitors the vacuum degree and environmental parameters of the vacuum chamber.

[0032] The device and method for preparing a diamond film glass substrate based on laser deposition of the present invention have the following beneficial effects compared with the prior art:

[0033] (1) During the deposition process, key parameters such as laser power, pulse frequency, and laser focus position are monitored; by precisely controlling these parameters of the laser system, the laser energy is ensured to be accurately focused on the surface of the glass substrate, achieving uniform growth and high-quality adhesion of the diamond film, and significantly improving the performance and stability of the film layer.

[0034] (2) By setting specific laser parameters, the effects of laser power, spot diameter, wavelength and pulse frequency on the growth of diamond film are taken into account. By utilizing the optimized combination of these parameters, the crystal structure and thickness of the diamond film are more accurately controlled. Through inverse process simulation and adjustment, high precision and consistency of the film layer are achieved. This enables the substrate to have better thermal expansion and mechanical strength, thereby improving the performance and reliability of the chip.

[0035] (3) During the deposition process, a precisely configured precursor gas mixture is used and laser deposition is performed in a vacuum environment, which reduces the generation of impurities and defects. At the same time, by annealing the deposited diamond film and testing its surface properties, dynamic factors such as time and temperature are taken into account, and the crystal quality and surface flatness of the film layer are improved more accurately, thereby improving the overall performance and application prospects of the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 is a flow chart of the preparation method of the present invention;

[0038] Figure 2 It is a schematic diagram of the preparation device of the present invention. DETAILED DESCRIPTION

[0039] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] like Figure 1 As shown, a method for preparing a diamond film glass substrate based on laser deposition of the present invention comprises the following steps:

[0041] S1, select glass material to prepare substrate 1, and clean the surface of substrate 1 to remove contaminants; at the same time, prepare a diamond film precursor gas mixture. The type of glass substrate is selected according to the application requirements. Commonly used materials include: 1) Borosilicate glass (for example, Corning7740): has good thermal stability and chemical corrosion resistance. 2) Aluminosilicate glass (for example, Corning7059): has high light transmittance and low thermal expansion coefficient. 3) Soda-lime glass: economical and practical, suitable for general applications. According to the equipment requirements and the performance of the final product, select a suitable glass substrate thickness, generally between 0.5mm and 2mm; thicker substrates provide better thermal stability and mechanical strength. According to the degree of contamination of the glass substrate, select a suitable cleaning method, including: using an ultrasonic cleaner for ultrasonic cleaning, immersing the substrate 1 in deionized water or a cleaning agent, usually the ultrasonic frequency is set at 40kHz, and the cleaning time is 5-10 minutes; using ethanol or acetone for chemical cleaning, soaking and wiping the substrate 1 to remove organic matter and oil stains. After cleaning is completed, an optical microscope or a scanning electron microscope (SEM) is used to check the cleaning effect on the surface of the substrate 1 to ensure that there is no obvious dirt or particles remaining on the surface.

[0042] Before laser deposition, the surface roughness of the glass substrate 1 can also be adjusted by mechanical polishing or chemical mechanical polishing (CMP) according to the deposition requirements of the diamond film. The target roughness is generally Ra < 5nm to ensure the uniformity of thin film deposition; and plasma treatment or flame treatment and other technologies are used to produce highly active sites on the surface of the substrate 1 to enhance the adhesion of the diamond film. Use an atomic force microscope (AFM) or a scanning electron microscope (SEM) to detect the surface morphology after cleaning, evaluate the surface flatness and roughness, and ensure that it meets the deposition requirements. A contact angle meter can also be used to test the contact angle of a water droplet on the surface of the substrate 1 to evaluate the hydrophilicity and energy of its surface to ensure that it is suitable for subsequent diamond film deposition.

[0043] S2, placing the substrate 1 in a vacuum environment, delivering the configured diamond film precursor gas mixture into the vacuum environment, and performing laser deposition on the surface of the substrate 1, so that the diamond film is evenly covered on the substrate 1. The specific steps are: ensuring that the laser parameters (power, frequency, focus) have been adjusted to appropriate values ​​(such as power: 500mW, frequency: 2kHz); starting the delivery of the gas mixture, ensuring that the gas flow is stable, usually setting the methane (CH4) flow rate to 100sccm, and the hydrogen (H2) flow rate to 900sccm; setting the deposition time according to the thickness requirements of the film layer, the common deposition time range is: 30 minutes to 1 hour for thin films, with a target thickness of 500nm to 1μm; 1 hour to 3 hours for thick films, with a target thickness of 1μm to 5μm.

[0044] S3, annealing and surface property testing of the diamond film deposited on substrate 1 to improve the quality and performance of the film. X-ray diffraction (XRD) analysis is performed to evaluate the crystal structure and quality of the film layer, with the goal of improving the crystallinity and purity of the film. The XRD spectrum should show obvious diamond characteristic peaks, indicating that the film layer is of good quality. The interplanar spacing d is calculated by Bragg's law as 2dsinθ=nλ, where θ is the diffraction angle; λ is the X-ray wavelength (generally 0.15406nm); n is the diffraction order, usually 1. Use a scanning electron microscope (SEM) or an atomic force microscope (AFM) to observe the surface morphology of the film layer, evaluate the grain size and surface roughness, and the expected roughness Ra is less than 10nm. Raman spectroscopy is used to detect the quality of the diamond film. The characteristic peak of diamond is at 1332cm-1, and the peak intensity and half-height width can be used to evaluate the crystal quality.

[0045] When evaluating the annealing effect of the diamond film, the XRD and Raman spectral data before and after annealing are compared, and the characteristic peak intensity increases and the half-height width decreases, indicating that the crystal quality has improved. Calculate the internal stress of the film layer σ=(E / (1-ν))×(Δd / d), where E is Young's modulus (about 1050GPa for diamond); ν is Poisson's ratio (about 0.1); Δd / d represents the relative change in the interplanar spacing. According to the stress and crystal quality, adjust the annealing temperature and time. For example, when the stress is too large, the annealing temperature can be reduced to 650℃ or the cooling time can be extended. Record the experimental data in the database and establish a relationship model between annealing parameters and film properties. Linear regression or machine learning methods can be used for model fitting to obtain the model y=β0+β1T+β2t+β3σ+∈, where y is the film performance (such as hardness, thermal conductivity, etc.), T is the annealing temperature, t is the annealing time, σ is the internal stress of the film layer, and ∈ is the error term. Nanoindentation test was performed on the diamond film to determine the hardness H and Young's modulus E of the film layer. The hardness calculation formula is H = P max / A, where P maxis the maximum load, and A is the contact area. The thermal diffusivity α of the diamond film was tested using the laser flash method, and then the thermal conductivity κ was calculated as α×ρ×C p , ρ is the density (diamond is about 3.51g / cm 3 ), C p is the specific heat capacity (about 0.52 J / g·K). The resistivity of the diamond film is measured by the four-probe method: ρ = (V / I) × (π / ln2), where V is voltage and I is current. The mechanical, thermal and electrical properties are combined to evaluate whether the diamond film meets the application requirements. Compared with traditional substrate materials, the advantages of diamond film glass substrate in high thermal conductivity, high hardness and electrical insulation are highlighted. By combining multi-physics field simulation and experimental data, a mechanical, thermal and electrical performance model of the film is constructed to predict its performance in different applications.

[0046] exist Figure 1 In a preferred embodiment shown, in step S1, methane and hydrogen are selected as precursor gases, and the mixing ratio of methane and hydrogen is set according to the deposition conditions and the expected film properties. Methane (CH4) is the main precursor gas, suitable for the deposition of diamond films, and its concentration is usually between 1% and 10%. Hydrogen (H2) is used to dilute methane and provide a reducing environment to ensure the quality of the diamond film, and its concentration can account for more than 90% of the mixed gas. Other gases are usually included, such as ethylene (C2H4), which can be used to adjust the properties of the film, but their proportions must be carefully controlled.

[0047] The volume ratio of methane to hydrogen is usually 1:9, which is suitable for the deposition of most diamond films. The hardness and conductivity of the film can be optimized by adjusting the methane concentration. A higher methane concentration can increase the growth rate of the film.

[0048] Use the following formula to calculate the required gas volumes of methane and hydrogen:

[0049] V (CH4) =V total ×C (CH4) / (C (CH4) +C (H2) ),

[0050] V (H2) =V total ×C (H2) / (C (CH4) +C (H2) ),

[0051] Among them, V total is the total gas volume, C (CH4) With C (H2) are the concentrations of methane and hydrogen, respectively.

[0052] Based on this calculation, combined with the real-time feedback control system, the time function of gas flow is introduced to dynamically calculate and adjust the gas flow. The time function is:

[0053] V (CH4) (t) = V total (t)×C (CH4) (t) / (C (CH4) (t)+C (H2) (t)),

[0054] The gas flow rate can be adjusted in real time as a function of time to optimize the deposition rate of the film layer.

[0055] exist Figure 1 In a preferred embodiment shown, in step S2, when the diamond film precursor gas mixture is transported into the vacuum environment where the substrate 1 is located, a gas flow prediction model based on machine learning is introduced to predict the changing trend of the gas flow of methane and hydrogen and dynamically adjust it to provide an ideal precursor gas environment for laser deposition of diamond film on the surface of the substrate 1.

[0056] exist Figure 1 In a preferred embodiment shown, a time series prediction model, such as a long short-term memory network (LSTM) or a regression model, can be used to predict the changing trend of the gas flow. The following is a detailed description of using a machine learning model to predict the gas flow and dynamically adjust it:

[0057] 1) Determine the data input type of the model and preprocess the data. The input data includes: historical gas flow data (for example: methane, hydrogen flow); environmental conditions (such as temperature, pressure, etc.), set to E(t); equipment parameters (such as current laser power, gas mixing ratio, etc.), set to P(t). We combine these data into an input feature matrix X(t) = [V (CH4) (t),V (H2) (t), E(t), P(t)], where t represents time.

[0058] 2) LSTM (Long Short-Term Memory Network) is used as the prediction model. LSTM is suitable for processing time series data and can learn time dependencies. The basic structure of the LSTM model is as follows:

[0059] h t =LSTM(X(t),h t-1 ),

[0060] Among them, h t is the hidden state (memory state) at time t, which is obtained by inputting the feature X(t) and the previous hidden state h t-1 Joint decision.

[0061] The predicted output is the gas flow at the next time step t+1

[0062]

[0063] Among them, f() is the traffic prediction function obtained through the LSTM network.

[0064] 3) Using mean square error (MSE) as the loss function, calculate the difference between the predicted value and the actual gas flow rate,

[0065]

[0066] Where N is the time step of the prediction, is the predicted value of the model at the t+ith time step, and V(t+i) is the actual gas flow. The loss function is optimized by back propagation algorithm and gradient descent, and the parameters of the LSTM model are updated to make the prediction results more accurate.

[0067] 4) The prediction model for the gas flow rate change trend of methane and hydrogen is:

[0068]

[0069] Where t is time, and are the predicted flow rates of methane and hydrogen at the next time step at time t, respectively. X(t) is the input feature matrix of the model. The input features of the model include the historical gas flow data, environmental conditions and equipment parameters of methane and hydrogen. t-1 is the hidden state at time t-1; θ is the trainable parameter of the model, which is updated every time new data is input, so that the model can better adapt to the dynamic changes of gas flow. Through this gas flow prediction model based on machine learning, the system can predict the changing trend of gas flow in advance and make dynamic adjustments based on the prediction results, thereby avoiding the impact of gas flow fluctuations on the deposition process and ensuring high-quality deposition of diamond films.

[0070] 5) Based on the predicted gas flow, the closed-loop control algorithm is used to dynamically adjust the gas flow of methane and hydrogen. The adjustment formulas are:

[0071]

[0072] in, and are the gas flow rates of methane and hydrogen adjusted for the next time step, and is the gas flow rate of methane and hydrogen in the current time step, α is the adjustment coefficient and is used to smooth the change of gas flow rate, and the value range of α is between 0 and 1.

[0073] exist Figure 1 In a preferred embodiment shown, in step S2, the deposition rate of the diamond film on the substrate 1 is adjusted by adjusting the laser power and the pulse frequency. The calculation formula of the deposition rate is R = (f × A) / D, where R is the deposition rate, f is the pulse frequency, A is the thickness of the material deposited per pulse, and A is the effective area of ​​the substrate 1. The pulse frequency range is 1Hz to 10kHz, which is conducive to adjusting the deposition rate and the quality of the film. Specifically, low frequency (1-500Hz) is suitable for thick film deposition, allowing the material to be fully cooled; medium frequency (500Hz-2kHz) is suitable for the deposition of medium-thick films; high frequency (2kHz-10kHz) is suitable for fast deposition of thin films.

[0074] exist Figure 1 In a preferred embodiment shown, in step S2, the deposition rate and the deposition thickness of the diamond film are monitored during the laser deposition process. Specifically, a monitoring device (such as an optical microscope, RHEED) is used to monitor the growth of the film layer in real time to ensure the uniformity and quality of the film layer. The growth rate of the film layer is R=D / t, where R is the deposition rate (in nm / s), D is the film thickness (in nm), and t is the deposition time (in s). For example, if the film thickness target is 1 μm and the deposition time is 1 hour (3600s), then the deposition rate R=1000nm / 3600s≈0.28nm / s. An adaptive frequency adjustment algorithm based on machine learning is introduced to optimize the pulse frequency, and the adjustment algorithm formula is,

[0075] f new =f old +β×(R target -R measured ),

[0076] Among them, β is the pulse frequency adjustment coefficient, R target is the target deposition rate, R measured The deposition rate is monitored in real time.

[0077] A power meter and a frequency meter can also be installed to monitor the laser power and frequency in real time to ensure their stability and set the monitoring values: power monitoring range: 0-1500mW; frequency monitoring range: 1Hz-10kHz.

[0078] At the same time, a feedback mechanism is set to ensure real-time adjustment of laser parameters. PID control algorithm can be used to adjust to keep laser parameters stable. The algorithm formula is:

[0079]

[0080] Among them, u(t) is the control output, e(t) is the current error, K p , Ki , K d They are proportional, integral and differential gains respectively.

[0081] exist Figure 1 In a preferred embodiment shown in FIG. 1 , in step S2 , the focus of the laser is adjusted so that the laser is focused on the surface of the glass substrate 1 , and the calculation formula for the spot diameter D of the laser focus is:

[0082] D = (2 × λ ​​× F) / (π × D0),

[0083] Wherein, λ is the laser wavelength, F is the focal length of the focusing lens, F ranges from 50 mm to 100 mm, D0 is the input diameter of the laser beam, and D ranges from 50 μm to 200 μm.

[0084] exist Figure 1 In a preferred embodiment shown in FIG. 1 , in step S3, the common annealing temperature range is 500°C to 800°C, and the annealing time depends on the film thickness and the required crystal quality. The general annealing time is 30 minutes to 2 hours. For example, for a film with a thickness of 1 μm, the annealing time can be set to 1 hour. Annealing should be performed in an inert gas (such as argon) or a high vacuum (<10 - 4 Pa) environment to prevent oxidation of the film. The gas purity should reach 99.999% to ensure a clean environment. Control the heating and cooling rates to avoid cracking of the film due to thermal stress. The heating and cooling rates are 5°C / min. The diamond film is annealed using the segmented annealing method. The temperature distribution formula during annealing can be expressed as:

[0085] T(t)=T0+ΔT×sin(πt / t f ),

[0086] Where T0 is the initial temperature, ΔT is the temperature variation range, t is the deposition time, and t f is the end time of the annealing process.

[0087] exist Figure 1 In a preferred embodiment shown in FIG. 1 , in step S3, when detecting the surface characteristics of the diamond film, an ellipsometer or a step profiler is used to measure the thickness of the diamond film, and the calculation formula is:

[0088]

[0089] And confirm whether the thickness of the diamond film meets the design requirements; and evaluate the uniformity of the film layer (for example, 1 μm) by detecting multiple positions of the diamond film, with a tolerance range of ±10%.

[0090] like Figure 2As shown, a diamond film glass substrate preparation device based on laser deposition of the present invention is used in a diamond film glass substrate preparation method based on laser deposition of any of the above embodiments, including a vacuum chamber 2, a laser device 3, a gas delivery system 4 and a control unit 5.

[0091] The substrate 1 is arranged in the vacuum chamber 2. The vacuum chamber 2 is usually made of high temperature and corrosion resistant materials, such as stainless steel. The volume of the vacuum chamber is between 50L and 200L to accommodate deposition of different scales; its vacuum degree is required to reach 10 -5 Up to 10 - 6 Torr high vacuum environment to reduce the impact of gas molecules on the deposited film.

[0092] Use a vacuum pump (such as a mechanical pump and a turbomolecular pump) to establish a vacuum environment. Specifically, start the mechanical pump to perform preliminary vacuuming until the vacuum degree reaches 10 -3 Torr; switch to the turbomolecular pump to further increase the vacuum to the target value (10 -5 Up to 10 -6 Torr).

[0093] The laser device 3 emits laser into the vacuum chamber 2 and is used to laser deposit diamond film on the surface of the substrate 1. A pulsed laser (such as a Nd laser) is selected as the laser emitting mechanism, and its laser wavelength is 1064nm. The adjustable range of the peak power is 100mW to 1500mW, which is usually set according to the film thickness requirements. The laser device 3 is divided into three gears: low power when the power is 100-300mW, which is suitable for initial film growth; medium power when the power is 500-800mW, which is suitable for accelerated film growth; high power when the power is 1000-1500mW, which is suitable for rapid deposition. The formula P=E / t can be used to calculate the power required for deposition, where P is the power (in W), E is the required energy (in J), and t is the deposition time (in s).

[0094] The gas delivery system 4 delivers the configured diamond film precursor gas mixture into the vacuum chamber 2. The gas delivery system 4 uses a high-precision gas flow valve to ensure the stability and adjustability of each gas flow. It is usually equipped with a mass flow meter (MFC) for real-time monitoring and adjustment, with an accuracy of ±0.5% FS. Before the mixed gas is delivered, methane and hydrogen will be input into the pre-mixed gas tank, and the methane and hydrogen will be mixed evenly according to the configured ratio; a stirring device can be used to improve the mixing uniformity and ensure that the mixed gas is not contaminated by the outside. After the mixing is completed, the mixed gas is analyzed by analytical means such as gas chromatography (GC) or mass spectrometry (MS) to ensure that the gas ratio is in line with expectations; according to the test results, the gas flow is adjusted in time to ensure the stability and suitability of the gas mixture, providing an ideal precursor gas environment for subsequent laser deposition. .

[0095] The control unit 5 is electrically connected to the vacuum chamber 2, the laser device 3 and the gas delivery system 4. The control unit 5 monitors and adjusts the power, pulse frequency and focus position of the laser device 3 in real time, adjusts the flow rate and proportion of the diamond film precursor gas mixture delivered by the gas delivery system 4, and monitors the vacuum degree and environmental parameters of the vacuum chamber 2.

[0096] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a diamond film glass substrate based on laser deposition, characterized in that: The following steps are included: S1, selecting a glass material to prepare a substrate (1), and preparing a diamond film precursor gas mixture; S2, placing the substrate (1) in a vacuum environment, transporting the configured diamond film precursor gas mixture into the vacuum environment, and performing laser deposition on the surface of the substrate (1) so that the substrate (1) is evenly covered with a diamond film; S3, annealing the diamond film deposited on the substrate (1) and detecting its surface properties.

2. The method for preparing a diamond film glass substrate based on laser deposition according to claim 1, characterized in that: In the step S1 , methane and hydrogen are selected as precursor gases, and the mixing ratio of methane and hydrogen is set according to deposition conditions and expected film properties.

3. The method for preparing a diamond film glass substrate based on laser deposition according to claim 2, characterized in that: In the step S2, when the diamond film precursor gas mixture is transported into the vacuum environment where the substrate (1) is located, a gas flow prediction model based on machine learning is introduced to predict the change trend of the gas flow of methane and hydrogen and perform dynamic adjustments to provide an ideal precursor gas environment for laser deposition of diamond film on the surface of the substrate (1).

4. The method for preparing a diamond film glass substrate based on laser deposition according to claim 3, characterized in that: The prediction model of the gas flow rate variation trend of methane and hydrogen is: Where t is time, and are the predicted flow rates of methane and hydrogen at the next time step at time t, respectively. X(t) is the input feature matrix of the model. The input features of the model include the historical gas flow data, environmental conditions and equipment parameters of methane and hydrogen. t-1 is the hidden state at time t-1, and θ is the trainable parameter of the model; The adjustment formulas for dynamically adjusting the gas flow rates of methane and hydrogen are: in, and are the gas flow rates of methane and hydrogen adjusted for the next time step, and is the gas flow rate of methane and hydrogen in the current time step, α is the adjustment coefficient and is used to smooth the change of gas flow rate, and the value range of α is between 0 and 1.

5. The method for preparing a diamond film glass substrate based on laser deposition according to claim 1, characterized in that: In the step S2, the deposition rate of the diamond film on the substrate (1) is adjusted by adjusting the laser power and the pulse frequency. The calculation formula of the deposition rate is: R=(f×A) / D, Wherein, R is the deposition rate, f is the pulse frequency, A is the thickness of the material deposited per pulse, and A is the effective area of ​​the substrate (1).

6. The method for preparing a diamond film glass substrate based on laser deposition according to claim 5, characterized in that: In step S2, the deposition rate and the deposition thickness of the diamond film are monitored during the laser deposition process, and an adaptive frequency adjustment algorithm based on machine learning is introduced to optimize the pulse frequency. The adjustment algorithm formula is: f new =f old +β×(R target -R measured ), Among them, β is the pulse frequency adjustment coefficient, R target is the target deposition rate, R measured The deposition rate is monitored in real time.

7. The method for preparing a diamond film glass substrate based on laser deposition according to claim 1, characterized in that: In the step S2, the focus of the laser is adjusted so that the laser is focused on the surface of the glass substrate (1). The calculation formula for the spot diameter D of the laser focus is: D = (2 × λ ​​× F) / (π × D0), Wherein, λ is the laser wavelength, F is the focal length of the focusing lens, F ranges from 50 mm to 100 mm, D0 is the input diameter of the laser beam, and D ranges from 50 μm to 200 μm.

8. The method for preparing a diamond film glass substrate based on laser deposition according to claim 1, characterized in that: In step S3, the diamond film is annealed by a segmented annealing method. The temperature distribution formula during annealing can be expressed as: T(t)=T0+ΔT×sin(πt / t f ), Where T0 is the initial temperature, ΔT is the temperature variation range, t is the deposition time, and t f is the end time of the annealing process.

9. The method for preparing a diamond film glass substrate based on laser deposition according to claim 1, characterized in that: In step S3, when detecting the surface characteristics of the diamond film, the thickness of the diamond film is measured using an ellipsometer or a step profiler, and it is confirmed whether the thickness of the diamond film meets the design requirements; The uniformity of the film layer is evaluated by testing multiple locations of the diamond film, and the tolerance range of the film thickness is ±10%.

10. A device for preparing a diamond film glass substrate based on laser deposition, characterized in that: A method for preparing a diamond film glass substrate based on laser deposition as described in any one of claims 1 to 9, include, A vacuum chamber (2) in which the substrate (1) is arranged; A laser device (3) emits laser light into the vacuum chamber (2) and is used to deposit a diamond film on the surface of the substrate (1) by laser; A gas delivery system (4) for delivering the configured diamond film precursor gas mixture into the vacuum chamber (2); The control unit (5) is electrically connected to the vacuum chamber (2), the laser device (3) and the gas delivery system (4). The control unit (5) monitors and adjusts the power, pulse frequency and focal position of the laser device (3) in real time. The control unit (5) adjusts the flow rate and proportion of the diamond film precursor gas mixture delivered by the gas delivery system (4). The control unit (5) monitors the vacuum degree and environmental parameters of the vacuum chamber (2).

Images