CN116660234A - In-situ Raman testing method and system in plasma environment - Google Patents

Abstract

The invention discloses an in-situ Raman spectrum test method and system in a plasma environment, wherein the in-situ Raman spectrum test system includes: a Raman test device and material growth equipment for growing samples in a plasma environment. The Raman testing device is used to emit a pulsed light signal to the material growth equipment and irradiate the sample grown on the material growth equipment, the pulsed light signal excites the sample to generate a pulsed Raman scattering signal, and is used in the The pulse Raman scattering signal is collected in the pulse time domain, and the Raman scattering spectrum is obtained through data processing. The in-situ Raman spectrum test system disclosed by the present invention emits pulsed light signals through the Raman test device and receives the Raman scattering signals in the pulsed time domain excited by the pulsed light signals, reducing the impact of stray light in the plasma environment on the Raman spectrum Test interference.

Description

In-situ Raman testing method and system in plasma environment

technical field

The present application relates to the field of on-line monitoring technology, in particular to an in-situ Raman testing method and system in a plasma environment.

Background technique

Carbon materials, such as diamond, diamond-like carbon, graphene, and carbon nanotubes, are important multifunctional materials with great application potential and scientific value, and are widely concerned as the frontier of new materials. Plasma chemical vapor deposition technology is suitable for preparing high-quality thin films and crystal materials with large area, good uniformity, high purity and good crystal morphology. It is an effective means to obtain high-end carbon materials. The relevant process parameters directly affect the gas phase growth environment in the reaction chamber , thereby affecting the quality of carbon materials. Raman spectroscopy is a necessary means to detect the structure and quality of carbon materials. It can accurately and quickly determine the structure, type, defects and impurities of carbon materials, so as to evaluate the quality and properties of materials.

In the existing situation, carbon materials are prepared in the material growth equipment, and the plasma in the reaction chamber emits strong light, which leads to interference in the Raman spectrum test. Therefore, how to eliminate the interference of the stray light in the carbon material preparation process on the Raman spectrum test has become a subject of research by those skilled in the art.

Contents of the invention

The main purpose of the embodiments of the present application is to provide an in-situ Raman test method and system in a plasma environment, aiming to provide an in-situ Raman test in a plasma environment that reduces stray light interference in Raman spectroscopy tests methods and systems.

In the first aspect, the embodiment of the present application provides an in-situ Raman spectroscopy testing system in a plasma environment, including:

Material growth equipment for growing samples in a plasma environment;

The Raman test device is used to emit pulsed light signals to the material growth equipment and irradiate the samples grown on the material growth equipment, and the pulsed light signals excite the samples to generate pulsed Raman scattering signals; and are used to collect pulsed Raman scattering signals in the pulse time domain , the Raman scattering spectrum was obtained after data processing.

In some embodiments, the Raman testing device includes a pulsed laser, and the pulsed light signal emitted by the pulsed laser transmitter is an ultraviolet pulse signal, and the wavelength of the pulse signal is less than 300 nm.

In some embodiments, the Raman testing device also includes a photodetector provided with an ICCD (enhanced charge-coupled device, IntensifiedCharge-coupled Device), and the photodetector is used to collect the Raman scattering signal in the pulse time domain of the pulsed Raman scattering signal .

In some embodiments, the Raman test device also includes a Raman test module, and the Raman test module includes a light emitting component, a light receiving component, a transflective component, and a light concentrating component;

Among them, the transflective component is arranged between the light emitting component and the light concentrating component, and the pulsed light signal emitted by the pulse laser is collimated by the light emitting component, and then focused and irradiated to the sample in the material growth equipment through the transflective component and the light concentrating component to excite The sample generates a pulsed Raman scattering signal, the transflective component reflects the pulsed Raman scattering signal to the light receiving component, and the light receiving component transmits the Raman scattering signal to the photodetector.

In some embodiments, the Raman test module also includes a filter assembly, and the filter assembly is arranged between the transflective assembly and the light receiving assembly;

Wherein, the light receiving component includes a mirror and a focusing lens;

The focusing lens is arranged between the reflector and the light detector, and the reflector is used to reflect the Raman scattering signal, so as to transmit the Raman scattering signal to the light detector through the focusing lens, and the transmission of the Raman scattering signal after being reflected by the reflector The direction is parallel to the light emitting direction of the light emitting component.

In some embodiments, the light-receiving component includes a reflector, a focusing lens, and a filter component;

The mirror is used to reflect the Raman scattering signal, so that the Raman scattering signal is transmitted to the photodetector through the focusing lens, and after being reflected by the mirror, the transmission direction of the side Raman scattering signal is parallel to the light emission direction of the light emitting component ;

The filter assembly is arranged between the reflection mirror and the focusing lens, or between the reflection mirror and the transflective assembly.

In some embodiments, the light emitting component includes an optical filter and a collimating mirror, and the optical filter and the collimating mirror are sequentially arranged in the light emitting direction, and the pulsed light signal emitted by the pulse laser is converted into ultraviolet monochromatic light after passing through the optical filter. .

In some embodiments, a material growth apparatus includes a reaction assembly and a sealing assembly;

Wherein, the reaction assembly includes a main body and an observation connection part connected to the main body, and the main body is formed with a reaction chamber for providing a growth environment for the sample; the observation connection part is formed with an observation channel that communicates with the reaction chamber and has an opening; the sealing The component is connected with the observation connection part, which is used to seal the opening of the observation channel, and make the opening of the observation channel form a light-transmitting part; the pulsed laser signal emitted by the Raman test device is irradiated from the observation channel to the sample in the reaction chamber through the light-transmitting part.

In the second aspect, the present application provides an in-situ Raman spectroscopy testing method in a plasma environment, which is applied to material growth equipment, including the following steps:

growing samples in reaction chambers of material growth equipment;

The Raman test device emits a pulsed laser signal into the reaction chamber and irradiates the surface of the sample to excite the sample to generate a pulsed Raman scattering signal;

The Raman testing device collects the pulse Raman scattering signal in the pulse time domain of the pulse Raman scattering signal, and obtains the Raman scattering spectrum through data processing.

In some embodiments, the pulsed laser signal emitted by the Raman testing device into the reaction chamber is an ultraviolet pulsed laser signal with a wavelength below 300 nm.

The in-situ Raman spectroscopy test method and system in a plasma environment provided by this application uses a Raman test module to emit a pulsed light signal and excite the sample to generate a pulsed Raman scattering signal, and the pulsed Raman signal of the sample is excited within one pulse time Compared with the continuous signal, the plasma fluorescence is stronger, which reduces the stray light interference accepted by the Raman test module, so as to obtain a clearer spectrum.

Icons: 10, material growth equipment; 11, reaction component; 111, main body; 112, observation connection part; 113, light-transmitting part; 12, sealing component; 13, sample;

20. Raman test device; 21. Shell; 22. Light emitting component; 23. Light receiving component; 24. Transflective component; 25. Concentrating component; 26. Filter component; 28. Pulse laser; Light sheet; 223, collimating mirror; 231, reflecting mirror; 232, focusing lens; 29, light detector;

30. Adapter assembly; 31. First adapter; 32. Second adapter; 321. First light transmission port; 322. Connection hole; 311. Bottom plate; 312. Side plate; 313. Through hole; 314 , Fixed hole.

Description of drawings

Fig. 1 is a schematic diagram of the explosion structure of the in-situ Raman testing system of the present invention;

2 is a schematic diagram of the light path of the Raman test module of the in-situ Raman test system of the present invention;

3 is a schematic diagram of the optical path of the Raman test module of another variant embodiment of the in-situ Raman test system of the present invention;

Fig. 4 is a schematic structural diagram of the adapter assembly of the in-situ Raman testing system of the present invention;

Fig. 5 is a flowchart of the in-situ Raman testing method of the present invention.

Detailed ways

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 part of the embodiments of the present application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

In the description of this application, unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral Connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in this application in specific situations.

At present, materials are prepared in material growth equipment in a plasma environment, and the plasma in the reaction chamber emits strong light, which leads to interference in Raman spectroscopy.

In order to solve the above problems, the present invention provides an in-situ Raman spectroscopy testing method and system in a plasma environment.

Some implementations of the present application will be described in detail below with reference to the accompanying drawings, and the following embodiments and features in the embodiments can be combined with each other if there is no conflict.

Please refer to FIG. 1 . FIG. 1 is an in-situ Raman spectroscopy testing system provided by an embodiment of the present application, including a material growth device 10 and a Raman testing device 20 .

The material growth apparatus 10 is used to grow a sample 13 in a plasma environment. The Raman testing device 20 is used to emit pulsed light signals to the material growth equipment 10 and irradiate the samples 13 grown on the material growth equipment 10 , and the pulsed light signals excite the samples 13 to generate pulsed Raman scattering signals. The Raman testing device 20 is also used to collect pulse Raman scattering signals in the pulse time domain, and obtain Raman scattering spectra through data processing.

Exemplarily, the material growth device 10 grows the sample 13 in a plasma environment, and the material growth device 10 may be Microwave Plasma Chemical Vapor Deposition (MPCVD, Microwave Plasma Chemical Vapor Deposition), or Plasma Enhanced Chemical Vapor Deposition (PECVD). , Plasma Enhanced Chemical VaporDeposition). The grown sample 13 can be diamond or other carbon materials, etc., and can also be other chemicals that need to be used for Raman spectroscopic testing.

In some embodiments, the material growth device 10 can also be a physical vapor deposition (PVD, Physical VapourDeposition) device, the PVD device grows the sample 13 in a plasma environment, and the Raman testing device 20 performs in-situ Raman on the sample 13 Spectrum test.

After adopting the above technical scheme, the Raman test device 20 emits a pulsed light signal and excites the sample 13 to generate a pulsed Raman scattering signal, and the pulsed Raman signal that excites the sample 13 within one pulse time is stronger than the plasma fluorescence of the continuous signal , reducing the stray light interference received by the Raman test module 20, thereby obtaining a clearer spectrum.

Please refer to FIG. 2 , in some embodiments, the Raman testing device 20 includes a pulsed laser 28 , the pulsed light signal emitted by the pulsed laser 28 is an ultraviolet pulsed signal, and the wavelength of the pulsed signal is less than 300 nm.

The plasmon luminescence spectrum is generally above 300nm, and the Raman scattering light signal of the laser excitation material below 300nm is below 300nm, so using the laser wavelength below 300nm can avoid the interference of plasma luminescence on the Raman scattering signal. And because the ultraviolet Raman signal is stronger than the visible light and infrared Raman signal, the shorter the wavelength, the larger the Raman scattering cross section and the stronger the Raman signal intensity. Under the same conditions, to produce the same intensity signal, the laser power required by UV is also smaller. Therefore, ultraviolet Raman detection is less affected by the interference of ambient light and background light, which helps to avoid the interference of background light caused by plasma luminescence, so as to obtain a clear spectrum.

In some embodiments, the material growth device 10 can also be Hot Filament Chemical Vapor Deposition (HFCVD, Hot Filament Chemical Vapor Deposition). The Raman spectroscopy test of 13 produced great interference. Since the luminescence is mainly visible light, using the ultraviolet Raman test can effectively avoid the interference of the filament luminescence on the Raman spectrum test.

Please refer to FIG. 2 , in some embodiments, the Raman testing device 20 further includes a photodetector 29 provided with an ICCD, and the photodetector 29 is used for collecting Raman scattering signals in the pulse time domain of the pulsed Raman scattering signals.

In some embodiments, it is characterized in that the Raman test device 20 further includes a Raman test module, and the Raman test module includes a light emitting component 22 , a light receiving component 23 , a transflective component 24 , and a light concentrating component 25 .

Among them, the transflective component 24 is arranged between the light emitting component 22 and the light concentrating component 25, and the pulsed light signal emitted by the pulse laser 28 is collimated by the light emitting component 22 and then focused and irradiated to the material through the transflective component 24 and the light concentrating component 25. The sample 13 in the growth device 10 excites the sample 13 to generate a pulsed Raman scattering signal, the transflective component 24 reflects the pulsed Raman scattering signal to the light receiving component 23, and the light receiving component 23 transmits the Raman scattering signal to the photodetector 29 . Exemplarily, the transflective component 24 may be a dichroic mirror or a dichroic mirror.

In some embodiments, the Raman test module further includes a filter assembly 26 , and the filter assembly 26 is disposed between the transflective assembly 24 and the light receiving assembly 23 .

Wherein, the light receiving component 23 includes a mirror 231 and a focusing lens 232 . The focusing lens 232 is arranged between the reflecting mirror 231 and the photodetector 29, and the reflecting mirror 231 is used to reflect the Raman scattering signal, so that the Raman scattering signal is transmitted to the photodetector 29 through the focusing lens 232, and reflected by the reflecting mirror 231 The transmission direction of the back Raman scattering signal is parallel to the light emitting direction of the light emitting component 22 . By setting the mirror 231 , the transmission direction of the lateral Raman scattering signal reflected by the mirror 231 is parallel to the light emission direction of the light emitting component 22 , so that the volume of the Raman testing device 20 is reduced.

Referring to FIG. 2 and FIG. 3 , the filter assembly 26 is disposed between the reflector 231 and the focusing lens 232 , or the filter assembly 26 is disposed between the reflector 231 and the transflective assembly 24 .

In some embodiments, the light emitting component 22 includes a filter 222 and a collimating mirror 223, the filter 222 and the collimating mirror 223 are arranged in sequence in the light emitting direction, and the pulsed light signal emitted by the pulse laser 28 passes through the filter 222 Then transform into ultraviolet monochromatic light.

Referring to FIG. 1 , in some embodiments, a material growth device 10 includes a reaction component 11 and a sealing component 12 .

Wherein, the reaction assembly 11 includes a main body 111 and an observation connecting portion 112 connected to the main body 111, and the main body 111 is formed with a reaction chamber for providing a growth environment for the sample 13; Observation channel with opening. The sealing assembly 12 is connected with the observation connection part 112 and is used for sealing the opening of the observation channel and making the opening of the observation channel form a light-transmitting part 113 . The pulsed laser signal emitted by the Raman testing device 20 is irradiated to the sample 13 in the reaction chamber through the light-transmitting part 113 through the observation channel.

Exemplarily, the sample 13 is a carbon material, such as carbon material such as diamond and graphene, and the material growth device 10 uses a microwave plasma chemical vapor deposition technique to prepare the carbon material. The sealing assembly 12 includes a flange and quartz glass, the flange and the quartz glass jointly seal the opening of the observation channel, and the quartz glass realizes light transmission. It can be understood that the sealing assembly 12 can have other ways to achieve sealing and light transmission, and there can also be multiple observation connecting parts 112 , which is not limited here.

Please refer to FIG. 1 and FIG. 4 , in some embodiments, the in-situ Raman spectroscopy testing system further includes an adapter assembly 30 for connecting the material growth equipment 10 and the Raman testing device 20 . Wherein, the adapter assembly 30 includes a first adapter 31 and a second adapter 32 .

The first adapter 31 is detachably connected to the observation connection part 112, and is provided with a through hole 313 corresponding to the light-transmitting part 113. The second adapter 32 is connected to the first adapter 31 and connected to the Raman test module. The housing 21 of 20 is detachably connected.

Exemplarily, the surface of the second adapter 32 is provided with a first light-transmitting port 321, and a connection hole 322 is provided around the first light-transmitting port 321. The housing 21 is provided with corresponding openings (not shown in the figure), and a connecting rod can be used One end is inserted into the connection hole 322 of the second adapter 32 , and the other end is inserted into a corresponding opening of the housing 21 to realize the connection between the adapter assembly 30 and the housing 21 . It can be understood that the connection between the housing 21 and the adapter assembly 30 can be selected in various ways, which are not limited here.

In some embodiments, the first adapter 31 includes a bottom plate 311 , a side plate 312 surrounding the bottom plate 311 , and an adapter fixing member (not shown).

Specifically, the through hole 313 is opened in the bottom plate 311, and the side plate 312 is provided with fixing holes 314 at intervals. Detachable connection.

Exemplarily, the fixing hole 314 may be provided with threads, and the transfer fixing member may be a screw. The first adapter 31 is sheathed on the observation connection part 112 , and a screw is screwed into the fixing hole 314 under the action of an external force to realize the connection between the observation connection part 112 and the first adapter 31 . Alternatively, the screw is screwed out of the fixing hole 314 under the action of an external force, so as to realize the disassembly of the first adapter 31 and the observation connecting portion 112 .

When it is necessary to perform in-situ Raman spectrum testing on the sample 13, the Raman test module 20 can be connected to the observation connection part 112 of the material growth equipment 10 through the adapter assembly 30, and the Raman test module 20 sends out an optical signal and the sample 13 is excited Raman scattering signals are transmitted through the light-transmitting part 113 , the through hole 313 corresponding to the first adapter 31 , and the first light-transmitting port 321 corresponding to the second adapter 32 . When it is not necessary to perform the Raman spectrum test, the connection between the adapter assembly 30 and the observation connection part 112 can also be selectively disconnected.

Please refer to Fig. 5, an embodiment of the present application provides an in-situ Raman spectroscopy testing method applied to material growth equipment, including the following steps:

101. A sample is grown in a reaction chamber of a material growth device;

In this embodiment, the samples are carbon materials, such as carbon materials such as diamond and graphene, and the carbon materials are prepared by microwave plasma chemical vapor deposition technology in the reaction chamber of the material growth equipment.

102. The Raman testing device emits a pulsed laser signal into the reaction chamber and irradiates the surface of the sample to excite the sample to generate a pulsed Raman scattering signal;

103. The Raman testing device collects pulsed Raman scattering signals in the pulse time domain of the pulsed Raman scattering signals, and obtains Raman scattering spectra through data processing.

In this embodiment, the Raman testing device collects Raman scattering signals in the pulse time domain through a photodetector with an ICCD.

Using the above-mentioned in-situ Raman spectroscopy test method, the pulsed Raman signal of the sample is excited within one pulse time, and the generated pulsed Raman signal is stronger than the plasma fluorescence of the continuous signal, which reduces the stray light received by the Raman test module Interference, so as to obtain a clearer spectrum.

In some embodiments, the pulsed laser signal emitted by the Raman testing device into the reaction chamber is an ultraviolet pulsed laser signal with a wavelength below 300 nm.

The plasma luminescence spectrum is generally above 300nm, while the Raman scattering light signal of the laser excitation material below 300nm is below 300nm, and because the ultraviolet Raman signal is stronger than the visible light and infrared Raman signal, the shorter the wavelength, the smaller the Raman scattering cross section. The larger the value, the stronger the Raman signal intensity. Under the same conditions, to produce the same intensity signal, the laser power required by UV is also smaller. Therefore, the ultraviolet Raman detection with a wavelength of 300nm is less affected by the interference of ambient light and background light, which helps to avoid the interference of background light caused by plasma luminescence, so as to obtain a clear spectrum.

Furthermore, the Raman testing device performs laser emission and Raman signal reception and detection through an observation window of the material growth equipment, so as to realize the detection of in-situ Raman scattering signals during the growth process of the sample.

The in-situ Raman spectroscopy testing method under the plasma environment of the present invention corresponds to the above-mentioned in-situ Raman spectroscopy testing system under the plasma environment. Example of a Raman spectroscopy testing system.

It should also be understood that the term "and/or" used in the description of the present application and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

The above is only a specific embodiment of the application, but the scope of protection of the application is not limited thereto. Any person familiar with the technical field can easily think of various equivalents within the scope of the technology disclosed in the application. Modifications or replacements, these modifications or replacements shall be covered within the scope of protection of this application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims (10)

1. An in-situ raman spectroscopy testing system in a plasma environment, comprising:

a material growth apparatus for growing a sample in a plasma environment;

the Raman testing device is used for emitting a pulse optical signal to the material growing equipment and irradiating the sample growing on the material growing equipment, and the pulse optical signal excites the sample to generate a pulse Raman scattering signal; and the method is used for collecting pulse Raman scattering signals in a pulse time domain and obtaining Raman scattering spectra through data processing.

2. The in situ raman spectrum testing system according to claim 1, wherein said raman testing device comprises a pulsed laser, wherein the pulsed light signal emitted from said pulsed laser emitter is an ultraviolet pulsed signal, and the wavelength of the pulsed signal is less than 300nm.

3. The in situ raman spectroscopy testing system according to claim 2, wherein said raman testing device further comprises a photodetector provided with an enhanced charge coupler (ICCD) for collecting raman scattering signals in the pulse time domain of the pulsed raman scattering signals.

4. The in situ raman spectrum testing system according to claim 3, wherein said raman testing device further comprises a raman testing module comprising a light emitting assembly, a light receiving assembly, a transflective assembly, and a light condensing assembly;

wherein the transreflective component is arranged between the light emitting component and the light condensing component, the pulse light signal emitted by the pulse laser is collimated by the light emitting component and then focused by the transreflective component and the light condensing component to irradiate the sample in the material growing equipment, the sample is excited to generate a pulse Raman scattering signal, the transflective assembly reflects the pulse Raman scattering signal to the light receiving assembly, and the light receiving assembly transmits the Raman scattering signal to the light detector.

5. The in situ raman spectrum testing system according to claim 4, wherein said raman test module further comprises a filter assembly disposed between said transflective assembly and said light receiving assembly;

wherein the light receiving assembly comprises a reflector and a focusing lens;

the focusing lens is arranged between the reflecting mirror and the light detector, the reflecting mirror is used for reflecting the Raman scattering signals, so that the Raman scattering signals are transmitted to the light detector through the focusing lens, and the transmission direction of the Raman scattering signals reflected by the reflecting mirror is parallel to the light emergent direction of the light emitting component.

6. The in situ raman spectroscopy system according to claim 4, wherein said light receiving assembly comprises a mirror, a focusing lens and a filter assembly;

the reflecting mirror is used for reflecting the Raman scattering signals so as to transmit the Raman scattering signals to the optical detector through the focusing lens, and the transmission direction of the side Raman scattering signals reflected by the reflecting mirror is parallel to the light emergent direction of the light emitting component;

the light filtering component is arranged between the reflecting mirror and the focusing lens or between the reflecting mirror and the transflective component.

7. The in-situ raman spectrum testing system according to claim 4, wherein said light emitting assembly comprises a light filter and a collimator lens, said light filter and said collimator lens are sequentially disposed in a light emitting direction, and a pulse light signal emitted from said pulse laser is converted into ultraviolet monochromatic light after passing through said light filter.

8. The in situ raman spectroscopy testing system of claim 1, wherein said material growth apparatus comprises a reaction assembly and a sealing assembly;

the reaction assembly comprises a main body part and an observation connecting part connected with the main body part, wherein the main body part is provided with the reaction cavity for providing a growth environment for a sample; the observation connection part is formed with an observation channel which is communicated with the reaction cavity and is provided with an opening; the sealing component is connected with the observation connecting part and is used for sealing the opening of the observation channel and enabling the opening of the observation channel to form a light transmission part; the pulse laser signal emitted by the Raman testing device irradiates the sample in the reaction cavity from the observation channel through the light transmission part.

9. The in-situ Raman spectrum testing method in the plasma environment is applied to material growth equipment and is characterized by comprising the following steps:

growing a sample within a reaction chamber of the material growth apparatus;

the Raman testing device emits a pulse laser signal into the reaction cavity and irradiates the surface of the sample, and excites the sample to generate a pulse Raman scattering signal;

the Raman test device collects the pulse Raman scattering signals in a pulse time domain of the pulse Raman scattering signals, and obtains Raman scattering spectra through data processing.

10. The in-situ raman spectrum testing method according to claim 9, wherein said pulsed laser signal emitted into said reaction chamber by said raman testing device is an ultraviolet pulsed laser signal having a wavelength of 300nm or less.