Optical film thickness monitoring system

Abstract

The invention discloses an optical film thickness monitoring system, and relates to the field of optical film plating, and the system comprises a laser emission assembly, an optical fiber, a detection assembly and a controller. The laser emitting assembly is used for emitting laser with different wavelengths; the optical fiber is arranged on an output light path of the laser emission assembly and is used for transmitting the laser with different wavelengths to the monitoring sheet; a to-be-measured film is deposited on the monitoring sheet, and laser energy changes after laser with different wavelengths penetrates through the monitoring sheet; the detection assembly is arranged on an output light path of the monitoring sheet and is used for detecting laser with different wavelengths after penetrating through the monitoring sheet and respectively generating a light current signal of each wavelength; the controller is connected with the detection assembly and used for calculating the thickness of the to-be-detected film on the monitoring piece according to the light current signal of each wavelength and controlling the deposition process of the film according to the thickness of the to-be-detected film so as to control the thickness of the to-be-detected film on the monitoring piece. According to the invention, the precision and stability of film thickness monitoring are improved.

Description

Technical Field

[0001] The present application relates to the field of optical coating, and particularly to an optical thin film thickness monitoring system for a multi-wavelength semiconductor laser light source combination. Background Art

[0002] There is a close relationship between the transmittance of an optical thin film and the thickness of the thin film, and this relationship has important application value in optical design and thin film preparation. Transmittance refers to the intensity ratio of the light after passing through the thin film to the incident light. As the thickness of the thin film changes, the transmittance also changes accordingly. The relationship between transmittance and thin film thickness usually exhibits one or more peaks, and these peaks correspond to integer multiples of the light wavelength in the thin film. When the thickness of the thin film is an integer multiple of the light wavelength, light undergoes constructive interference between the two interfaces of the thin film, resulting in more light being able to pass through the thin film, thereby making the transmittance reach a peak.

[0003] In occasions where it is necessary to monitor the thickness of an optical thin film, a continuous spectrum light source that can generate a continuous spectrum, such as a tungsten halogen lamp, etc., is generally used as the monitoring light source. After the continuous light passes through the monitoring film or is reflected by the film to be monitored, it is spectrally selected by a grating monochromator to select the corresponding wavelength and is received by a detector. The energy received by the detector will change with the change of the film thickness on the monitoring film, and then the change law of the thin film thickness is obtained through the change of the light energy.

[0004] In actual optical film thickness monitoring applications, due to the low spectral energy density of the continuous light source, the resolution of the grating monochromator is inversely proportional to the energy received by the detector. Therefore, the grating monochromator has disadvantages in actual applications: in low-resolution applications, the output wavelength bandwidth is relatively wide, affecting the monitoring accuracy; in high-resolution applications, the energy of the output wavelength is low, affecting the signal-to-noise ratio of the system; the positioning stability of the grating monochromator is insufficient, affecting the repeatability of actual coating indicators. Summary of the Invention

[0005] The purpose of the present application is to provide an optical thin film thickness monitoring system, which can improve the accuracy and stability of thin film thickness monitoring.

[0006] To achieve the above purpose, the present application provides the following solutions:

[0007] The present application provides an optical thin film thickness monitoring system, including:

[0008] A laser emission component, configured to emit lasers of different wavelengths;

[0009] An optical fiber, arranged on the output optical path of the laser emission component, configured to transmit lasers of different wavelengths to the monitoring film; the monitoring film is used for depositing the thin film to be measured, and the laser energy changes after the lasers of different wavelengths pass through the monitoring film;

[0010] A detection component is arranged on the output optical path of the monitoring film, and is used for detecting lasers of different wavelengths after passing through the monitoring film, and respectively generating photocurrent signals of each wavelength.

[0011] A controller is connected to the detection component, and is used for calculating the thickness of the thin film to be measured on the monitoring film according to the photocurrent signals of each wavelength, and controlling the film deposition process according to the thickness of the thin film to be measured, so as to control the thickness of the thin film to be measured on the monitoring film.

[0012] Further, the controller is also connected to the laser emission component, and the controller is also used for controlling the wavelength of the laser emitted by the laser emission component.

[0013] Further, the laser emission component includes a plurality of semiconductor lasers with different wavelengths.

[0014] Further, the controller is also connected to each semiconductor laser, and the controller is also used for controlling the working states of the semiconductor lasers, so as to control the wavelength of the laser emitted by the laser emission component.

[0015] Further, the optical fiber is an energy homogenization optical fiber; the energy homogenization optical fiber is also used for homogenizing the energy distribution of the laser transmitted inside.

[0016] Further, the optical thin film thickness monitoring system further includes: an optical fiber collimator, which is arranged between the optical fiber and the monitoring film, and is used for shaping the laser output by the optical fiber into a parallel light beam and making it incident on the monitoring film.

[0017] Further, the detection component includes a plurality of photodetectors and a plurality of analog-to-digital converters;

[0018] The plurality of photodetectors are all arranged on the output optical path of the monitoring film; one analog-to-digital converter is connected to one photodetector, and the plurality of analog-to-digital converters are all connected to the controller;

[0019] Each photodetector is used for detecting a laser of one wavelength after passing through the monitoring film and generating a photocurrent analog signal corresponding to the wavelength;

[0020] The analog-to-digital converter is used for converting the photocurrent analog signal corresponding to the wavelength into a digital signal to obtain a photocurrent signal corresponding to the wavelength.

[0021] Further, the monitoring film is located in a vacuum chamber.

[0022] Further, the monitoring film is an optical glass monitoring film.

[0023] Further, the controller controls the deposition process of the thin film by controlling the electron beam emitted by the electron gun; wherein, the electron gun emits an electron beam to heat and evaporate the film material, so that the film material forms vapor and deposits on the monitoring wafer.

[0024] According to the specific embodiments provided by the present application, the present application has the following technical effects:

[0025] The present application provides an optical thin film thickness monitoring system. By using lasers with different wavelengths to monitor the thickness of the thin film to be measured, it can not only improve the measurement accuracy and sensitivity, but also effectively eliminate the interference factors and errors that may occur during single-wavelength monitoring, thereby improving the accuracy and stability of thin film thickness monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0027] Figure 1 It is a schematic diagram of an optical thin film thickness monitoring system provided by an embodiment of the present application.

[0028] Reference numerals: 1 - laser emission component, 11 - semiconductor laser, 2 - optical fiber, 3 - optical fiber collimator, 4 - monitoring wafer, 5 - vacuum chamber, 6 - vacuum window, 7 - electron gun, 8 - detection component, 81 - photodetector, 82 - amplifier, 83 - analog-to-digital converter, 9 - controller. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0030] To make the above objects, features, and advantages of the present application more obvious and understandable, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0031] In an exemplary embodiment, as Figure 1 shown, an optical thin film thickness monitoring system is provided, including: a laser emission component 1, an optical fiber 2, a detection component 8, and a controller 9.

[0032] (1) The laser emission component 1 is used to emit lasers of different wavelengths.

[0033] In a specific application example, the laser emission component 1 includes a plurality of semiconductor lasers 11 of different wavelengths.

[0034] The semiconductor laser 11, also known as a laser diode, is a laser using semiconductor materials as the working substance. The semiconductor laser 11 refers to a semiconductor device that generates laser through stimulated emission transition of electrons by means of electrical injection, optical excitation, etc. The characteristics of semiconductor lasers are mainly reflected in the following four aspects:

[0035] ① High energy: The energy of the single wavelength of the laser is very high, which can be tens of thousands of times higher than the spectral energy of ordinary white light.

[0036] ② Good directivity: The divergence angle of the laser after emission is very small, almost emitted along a parallel direction, which makes the directivity of the laser particularly good. The light emitted by ordinary light sources propagates in all directions with a large divergence angle. In contrast, the directivity advantage of the laser is obvious.

[0037] ③ Good monochromaticity: The wavelength range of the laser is very narrow, so its color is very pure, the monochromaticity is very good, and at the same time, the wavelength output stability is good with small drift.

[0038] ④ Good coherence: The laser light waves emitted from the laser are consistent in wavelength, frequency, and polarization direction, which makes the laser have extremely strong coherence.

[0039] In order to further highlight the advantages of this application, the performance differences between the traditional grating monochromator and the laser emission component 1 of this application in thin film thickness monitoring are compared below.

[0040] 1) Energy output comparison.

[0041] Grating monochromators usually rely on continuous light sources such as tungsten halogen lamps. The energy distribution of these light sources is relatively dispersed, and the light intensity of each wavelength is low. In low-resolution applications, the relatively wide output wavelength bandwidth will affect the monitoring accuracy; in high resolution, due to the low spectral energy, it affects the signal intensity of the detector, resulting in a decrease in the signal-to-noise ratio.

[0042] The laser emitted by the laser emission component 1 of this application has high energy output and high monochromaticity. The output energy of each laser wavelength is concentrated, significantly improving the signal intensity and signal-to-noise ratio. This characteristic can effectively suppress background noise, thereby improving the measurement accuracy of the thin film thickness.

[0043] 2) Repeatability comparison.

[0044] Due to the use of continuous light sources such as tungsten halogen lamps in grating monochromators, the stability of these light sources is poor and they are easily affected by factors such as temperature fluctuations and light source attenuation, resulting in poor repeatability. Especially during long-term operation, the accuracy of thin film thickness monitoring may be affected.

[0045] The semiconductor laser 11 used in the laser emission component 1 of this application has excellent wavelength stability and low drift characteristics, and can maintain the stability of the output wavelength during long-term use, ensuring the repeatability of measurement.

[0046] 3) Complexity comparison.

[0047] Grating monochromators usually require multiple optical elements, such as continuous light sources, gratings, filters, optical fibers, etc. The structure is complex and the volume is large. The wavelength switching of grating monochromators depends on mechanical rotation, which increases the operation complexity and response time, and the wear of the mechanical part may lead to a decrease in stability.

[0048] Through an integrated design, the laser emission component 1 of this application couples lasers of multiple wavelengths into an optical fiber 2, and the output end outputs a parallel light beam through an optical fiber collimator 3, simplifying the optical design. There is no need for mechanical moving parts to switch wavelengths, the structure is more compact and stable, and the response speed is faster, reducing the operation complexity.

[0049] (2) The optical fiber 2 is arranged on the output optical path of the laser emission component 1. The optical fiber 2 is used to transmit lasers of different wavelengths to the monitoring film 4. The monitoring film 4 is used for depositing the thin film to be measured. After the lasers of different wavelengths pass through the monitoring film 4, the laser energy changes.

[0050] In a specific application example, after passing through multiple optical elements, the laser beam is easily affected by effects such as reflection and scattering, generating coherent noise. To effectively reduce this problem, the optical fiber 2 of this application uses an energy homogenization optical fiber. The energy homogenization optical fiber is also used to homogenize the energy distribution of the laser transmitted inside.

[0051] The light passing diameter of the energy homogenization optical fiber is larger than that of a common optical fiber, and the energy homogenization optical fiber can be designed as a square structure to break up the single mode of the laser propagating in the optical fiber, generate more modes, and average the energy into different modes to obtain the effect of uniform energy distribution. The process of breaking up the laser propagation mode is also the process of reducing the laser coherence length. The more modes there are, the shorter the coherence length.

[0052] Due to the high coherence of the laser, its long coherence length may cause coherent noise when passing through optical elements. By using an energy homogenizing optical fiber, the energy of the laser can be evenly distributed across the cross-section of the fiber, thus avoiding the uneven light intensity distribution with too strong a center and too weak an edge in the light beam. After homogenization at the light beam output end, the interference and noise caused by local light intensity differences can be effectively reduced.

[0053] In addition, the energy homogenizing optical fiber also reduces the optical wave interference effect caused by too long a coherence length by shortening the effective coherence length of the laser, making the laser beam more stable when passing through the optical path and greatly reducing the noise level.

[0054] In a specific application example, the monitoring film 4 is located inside the vacuum chamber 5. The vacuum chamber 5 is provided with a plurality of vacuum windows 6. The monitoring film 4 is an optical glass monitoring film.

[0055] (III) The detection component 8 is arranged on the output optical path of the monitoring film 4. The detection component 8 is used to detect the laser of different wavelengths after passing through the monitoring film 4 and generate photocurrent signals for each wavelength respectively.

[0056] In a specific application example, the detection component 8 includes a plurality of photodetectors 81 and a plurality of analog-to-digital converters 83. A plurality of photodetectors 81 are all arranged on the output optical path of the monitoring film 4. One analog-to-digital converter 83 is connected to one photodetector 81, and a plurality of analog-to-digital converters 83 are all connected to the controller 9. The detection component 8 further includes a plurality of amplifiers 82, and one amplifier 82 is connected to one photodetector 81.

[0057] Each photodetector 81 is used to detect the laser of one wavelength after passing through the monitoring film 4 and generate a photocurrent analog signal corresponding to the wavelength. The amplifier 82 is used to amplify the photocurrent analog signal.

[0058] The analog-to-digital converter 83 is used to convert the photocurrent analog signal corresponding to the wavelength into a digital signal to obtain the photocurrent signal corresponding to the wavelength.

[0059] (IV) The controller 9 is connected to the detection component 8. The controller 9 is used to calculate the thickness of the thin film to be measured on the monitoring film 4 according to the photocurrent signal of each wavelength, and control the film deposition process according to the thickness of the thin film to be measured to control the thickness of the thin film to be measured on the monitoring film 4.

[0060] In a specific application, the controller 9 can adopt a terminal device such as a computer.

[0061] In another exemplary embodiment, the controller 9 is further connected to the laser emission component 1, and the controller 9 is further configured to control the wavelength of the laser emitted by the laser emission component 1. Specifically, the controller 9 is connected to each semiconductor laser 11, and controls the wavelength of the laser emitted by the laser emission component 1 by controlling the operating states of the semiconductor lasers 11.

[0062] The controller 9 controls the deposition process of the thin film by controlling the electron beam emitted by the electron gun 7. Among them, the electron gun 7 emits an electron beam to heat and evaporate the film material, so that the film material forms vapor and deposits on the monitoring wafer 4. The electron gun 7 is located inside the vacuum chamber 5.

[0063] In another exemplary embodiment, the thin film to be measured can also be deposited on the monitoring wafer by means of magnetron sputtering, ion beam sputtering, etc. That is, the optical thin film thickness monitoring system provided in the present application can also be applied to a magnetron sputtering system or an ion beam sputtering system, and the corresponding deposition process can be selected according to requirements during actual application.

[0064] In another exemplary embodiment, the controller 9 can select different lasers to emit light, so that the laser output by the optical fiber 2 has different wavelengths.

[0065] In another exemplary embodiment, the optical thin film thickness monitoring system further includes an optical fiber collimator 3.

[0066] (5) The optical fiber collimator 3 is arranged between the optical fiber 2 and the monitoring wafer 4. The optical fiber collimator 3 is configured to shape the laser output by the optical fiber 2 into a parallel beam and incident on the monitoring wafer 4. In order to ensure that the laser can be accurately projected onto the photodetector 81, the present application installs an optical fiber collimator 3 at the output end of the optical fiber 2 to further improve the directivity of the beam, thereby improving the stability and signal-to-noise ratio of the optical thin film thickness monitoring system.

[0067] To better understand the technical solution of the present application, the following introduces the process of monitoring the thickness of the optical thin film in the present application:

[0068] ① The semiconductor laser 11 selected by the controller 9 emits a laser with a corresponding wavelength and is coupled into the energy homogenizing optical fiber.

[0069] ② Lasers with different wavelengths enter the vacuum chamber 5 as parallel light after passing through the optical fiber collimator 3 and are incident on the glass monitoring wafer.

[0070] ③The electron gun 7 emits an electron beam to heat and evaporate the film material. The film material forms vapor and is simultaneously deposited on the glass monitor and the coating substrate. The laser energy passing through the glass monitor changes, and through the beam splitter, it is decomposed into lasers of different wavelengths to be detected by the corresponding laser detectors, forming two photocurrents. The coating substrate is the substrate that needs to be coated during actual application. By monitoring the thickness of the film on the glass monitor, the thickness of the film on the coating substrate can be monitored simultaneously.

[0071] ④Amplify the two photocurrents respectively and convert the analog signals into digital signals to be read by the controller 9.

[0072] ⑤The controller 9 extracts the photocurrent signals of different wavelengths, converts them into optical thicknesses of their respective wavelengths through calculation, and then precisely controls the film thickness.

[0073] In the thickness monitoring of the optical film in this application, multiple lasers of different wavelengths are used for monitoring, which can significantly improve the measurement accuracy, sensitivity, and reliability of the optical film thickness, and at the same time simplify the structure of the optical film thickness monitoring system. The beneficial effects of this application include the following points:

[0074] 1) Improve the measurement accuracy and precision.

[0075] The film thickness has different transmittance responses to light of different wavelengths. In film thickness monitoring, transmittance is one of the commonly used measurement parameters. The propagation and transmission of light of different wavelengths in the film are different, mainly due to the following reasons:

[0076] Optical interference effect: The interference effect of the film is closely related to the wavelength of the light wave. If the thickness of the film is close to an integer multiple of some light waves, the transmittance will show a peak. These peaks are closely related to the wavelength. Therefore, using lasers of different wavelengths can effectively capture the optical interference effects in different thickness ranges. By comparing the transmittances at different wavelengths, the film thickness can be estimated more precisely.

[0077] Wavelength-dependent refractive index: Light of different wavelengths has different propagation speeds in the film, resulting in different refractive indices. When multiple wavelengths are used, the differences in the propagation speeds of lasers of different wavelengths in the film can provide more optical information, which helps to accurately calculate the film thickness.

[0078] 2) Enhance the adaptability of the film material.

[0079] Optical films usually consist of multiple material layers, and the optical properties (such as refractive index, absorption coefficient, etc.) of different material layers have different effects on the reflection and transmission of light. By selecting multiple lasers of different wavelengths for monitoring, the optical characteristics of different material layers can be more accurately reflected, and more reliable thickness data can be obtained.

[0080] In complex multi-layer films, lasers of different wavelengths can better resolve the thickness changes of each layer. By appropriately selecting the wavelengths, the mutual interference between different layers can be minimized, improving the accuracy of monitoring. For example, if multiple wavelengths act on different layers of the thin film respectively, more accurate thickness information of different layers can be obtained. Especially when the thin film structure is complex or the refractive index difference between film layers is large, measurements at multiple wavelengths will provide more independent data, effectively reducing errors.

[0081] 3) Reduce spectral interference and improve the signal-to-noise ratio.

[0082] During the actual film coating process, due to the influence of factors such as ambient light, background noise, and stray light of the thin film itself, the monitoring of a single wavelength may be interfered with, resulting in inaccurate measurements. Using lasers of multiple different wavelengths can effectively eliminate these interference factors, thereby improving the reliability of the measurements.

[0083] Suppress background noise: Lasers have very high monochromaticity and a narrow spectral line width, enabling the effective suppression of the influence of background light when monitoring the thickness of thin films. If only relying on one wavelength, background noise (such as ambient light or other irrelevant light sources) may lead to low or unstable signal intensity, thereby affecting the accuracy. However, when using multiple different wavelengths, some measurement errors caused by background noise can be automatically eliminated by comparing the transmittance changes at different wavelengths.

[0084] Improve the signal-to-noise ratio: Under the same detector conditions, by simultaneously monitoring the signals of multiple wavelengths, the overall signal intensity is enhanced, thereby improving the signal-to-noise ratio.

[0085] 4) Improve measurement sensitivity and real-time response.

[0086] Real-time monitoring and adjustment: By using lasers of multiple wavelengths, it is possible to respond more quickly to changes in the thickness of the thin film, especially in the rapidly changing film coating process. Since the response speeds of multiple wavelengths are different, the dynamic changes of the film layer at different wavelengths can be captured. By real-time monitoring the transmittance of two wavelengths, deviations can be detected earlier during the growth of the film layer, and adjustments can be made in a timely manner to prevent the film layer thickness from exceeding the set range.

[0087] Enhance sensitivity: Especially in the case of very small changes in the thickness of the thin film, lasers of multiple different wavelengths can provide more measurement points, enhancing sensitivity. For example, when the change in the thickness of the thin film is at the micron or nanometer level, the change amplitude of the transmittance at multiple wavelengths can reflect more subtle thickness fluctuations than single-wavelength monitoring.

[0088] 5) Improve flexibility and adaptability.

[0089] Flexibility in wavelength selection: Different wavelengths are suitable for different types of thin film materials. In some cases, it may be necessary to monitor the transmittance at specific wavelengths to obtain higher resolution or more suitable sensitivity. By adjusting the combination of different wavelengths, it is possible to adapt to different thin film materials, thickness ranges, or process requirements.

[0090] Process adaptability: For different thin film production processes, there may be different requirements. For example, some processes require faster thickness monitoring or are more sensitive to the film layer at specific wavelengths. Through the laser emission components with multiple wavelengths, the selection of the monitoring wavelength can be flexibly adjusted under different process conditions.

[0091] In summary, the present application uses lasers with multiple different wavelengths to monitor the thickness of thin films, which can not only improve the measurement accuracy and sensitivity but also effectively eliminate the interference factors and errors that may occur during single-wavelength monitoring. By combining the advantages of different wavelengths, more thin film thickness information can be provided, enhancing the stability, signal-to-noise ratio, response speed, and adaptability of the monitoring system.

[0092] It should be noted that the data involved in the present application (including but not limited to the data for analysis, stored data, displayed data, etc.) are all information and data authorized by the user or fully authorized by all parties, and the collection, use, and processing of relevant data need to comply with relevant regulations.

[0093] In the present application, all actions of obtaining signals, information, or data are carried out on the premise of complying with the corresponding data protection regulations and policies of the country where the device is located and with the authorization given by the owner of the corresponding device.

[0094] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as these technical feature combinations do not conflict, they should all be considered as within the scope described in this specification.

[0095] Specific examples are used in this article to elaborate on the principles and implementation methods of the present application. The descriptions of the above embodiments are only used to help understand the method and its core idea of the present application. At the same time, for those of ordinary skill in the art, based on the idea of the present application, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. An optical thin film thickness monitoring system, characterized in that The optical thin film thickness monitoring system includes: A laser emission component for emitting lasers of different wavelengths; An optical fiber disposed on the output optical path of the laser emission component for transmitting lasers of different wavelengths to a monitoring film; a thin film to be measured is deposited on the monitoring film, and the laser energy changes after the lasers of different wavelengths pass through the monitoring film; A detection component disposed on the output optical path of the monitoring film for detecting lasers of different wavelengths that have passed through the monitoring film and respectively generating photocurrent signals for each wavelength; A controller connected to the detection component for calculating the thickness of the thin film to be measured on the monitoring film according to the photocurrent signals for each wavelength and controlling the deposition process of the thin film according to the thickness of the thin film to be measured, so as to control the thickness of the thin film to be measured on the monitoring film.

2. The optical thin film thickness monitoring system according to claim 1, wherein The controller is further connected to the laser emission component, and the controller is further used to control the wavelength of the laser emitted by the laser emission component.

3. The optical thin film thickness monitoring system according to claim 1, characterized in that, The laser emission component includes a plurality of semiconductor lasers of different wavelengths.

4. The optical thin film thickness monitoring system according to claim 3, characterized in that, The controller is further connected to each semiconductor laser, and the controller is further used to control the working state of each semiconductor laser to control the wavelength of the laser emitted by the laser emission component.

5. The optical thin film thickness monitoring system according to claim 1, characterized in that The optical fiber is an energy homogenizing optical fiber; the energy homogenizing optical fiber is further used to homogenize the energy distribution of the laser transmitted inside.

6. The optical thin film thickness monitoring system according to claim 1, wherein The optical thin film thickness monitoring system further includes: An optical fiber collimator disposed between the optical fiber and the monitoring film for shaping the laser output from the optical fiber into a parallel beam and incident on the monitoring film.

7. The optical thin film thickness monitoring system according to claim 1, wherein, The detection component includes a plurality of photodetectors and a plurality of analog-to-digital converters; A plurality of photodetectors are all disposed on the output optical path of the monitoring film; one analog-to-digital converter is connected to one photodetector, and a plurality of analog-to-digital converters are all connected to the controller; Each photodetector is used to detect a laser of one wavelength that has passed through the monitoring film and generate a photocurrent analog signal corresponding to the wavelength; The analog-to-digital converter is used to convert the photocurrent analog signal corresponding to the wavelength into a digital signal to obtain the photocurrent signal corresponding to the wavelength.

8. The optical thin film thickness monitoring system according to claim 1, wherein The monitoring film is located in a vacuum chamber.

9. The optical thin film thickness monitoring system according to claim 1, characterized in that The monitoring film is an optical glass monitoring film.

10. The optical thin film thickness monitoring system according to claim 1, characterized in that, The controller controls the deposition process of the thin film by controlling the electron beam emitted by an electron gun; wherein, the electron gun emits an electron beam to heat and evaporate the film material, so that the film material forms vapor and deposits on the monitoring film.

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