Confocal fluorescence spectrum testing system
By designing a tilted test head module and objective lens module with overlapping focal points in a confocal fluorescence spectroscopy testing system, combined with a switching module and deep ultraviolet laser excitation, the problem of difficult acquisition of fluorescence signals from high-Al content AlGaN materials was solved, achieving efficient fluorescence signal collection and measurement.
Patent Information
- Application Number
- CN202411087839.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-09
- Publication Date
- 2026-02-10
AI Technical Summary
Existing confocal fluorescence spectroscopy systems struggle to effectively obtain fluorescence signals from AlGaN materials with high Al content because when the surface is excited along the c-axis of the crystal, very little fluorescence is emitted from the front.
By designing the main axis of the test head module to be tilted relative to the main axis of the objective lens module, and setting the focal point of the objective lens module and the focal point of the test head module at the same point, fluorescence signals emitted from different directions on the sample surface are collected. The switching module controls the on/off of the imaging and detection optical paths. Deep ultraviolet laser is used to excite the fluorescence and filter it through a filter. The fluorescence signal is transmitted to the test instrument body using a triaxial drive module and optical fiber.
The method enables efficient collection and measurement of fluorescence signals from AlGaN materials with high Al content, improving the efficiency of fluorescence signal acquisition. In particular, fluorescence that can propagate laterally during surface excitation along the c-axis of the crystal can be effectively collected.
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Figure CN121499441A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the semiconductor field, specifically to a confocal fluorescence spectroscopy testing system. Background Technology
[0002] With the development of emerging semiconductor devices, the variety of semiconductor materials is increasing. For fourth-generation semiconductors, wide-bandgap semiconductor materials include: GaN (3.3-3.4 eV), Ga2O3 (3.9 eV), SiC (3.3-3.4 eV), diamond (5 eV), and AlGaN (6.2 eV). Measuring their fluorescence spectra is crucial.
[0003] AlGaN, as an important component of semiconductor materials, is subject to spectral measurements. When the Al content exceeds 50%, the emission wavelength is <250nm, and its band structure exhibits band reversal (light and heavy holes). Using existing confocal fluorescence spectroscopy systems, when exciting the surface along the c-axis of the crystal, very little fluorescence is emitted from the front, making it difficult to obtain fluorescence signals from AlGaN materials with high Al content. Summary of the Invention
[0004] To solve the above-mentioned technical problems, this application provides the following technical solution:
[0005] This application provides a confocal fluorescence spectroscopy testing system, comprising:
[0006] A sample loading assembly;
[0007] The display component has a built-in imaging optical path and an objective lens module at one end of the display component. The objective lens module is positioned close to the sample on the material carrier component.
[0008] The light processing component contains a detection optical path, one end of which guides the objective lens module.
[0009] The testing component includes a testing instrument body and a testing head module. The testing instrument body has a first input terminal and a second input terminal. The other end of the detection optical path is directed to the first input terminal, and the testing head module is communicatively connected to the second input terminal. The testing head module is used to detect the sample on the material carrier assembly.
[0010] The main axis of the test head module is tilted relative to the main axis of the objective lens module, and the focal point of the objective lens module and the focal point of the test head module are at the same point.
[0011] In one embodiment, the beam path is a shared portion of the imaging optical path and the detection optical path;
[0012] A switching module is set at the intersection of the imaging optical path and the detection optical path, and the switching module is set close to the objective lens module.
[0013] In one embodiment, the switching module has a built-in motion unit, and the switching module can switch between a first position and a second position.
[0014] When the switching module moves to the first position, the imaging optical path is in the open state and the detection optical path is cut off;
[0015] When the switching module moves to the second position, the detection optical path is in the open state, and the imaging optical path is cut off.
[0016] In one embodiment, the optical processing component includes an optical path module, which has a built-in filter and a focusing plate; the filter and the focusing plate are located on the detection optical path;
[0017] The light processing assembly also includes an excitation light module, which is positioned close to the optical path module. The excitation light emitted by the excitation light module is guided by a filter and transmitted to the objective lens module via the detection optical path. The objective lens module then projects and focuses the light onto the sample loaded in the material carrier assembly.
[0018] In one embodiment, the detection optical path includes a coupling optical path;
[0019] A coupling module is provided between the optical path module and the switching module in the display component. The coupling optical path is built into the coupling module, and light is transmitted between the filter and the switching module through the coupling optical path.
[0020] In one embodiment, the display component includes an imaging module and an illumination module, with the imaging module and objective lens module disposed at opposite ends of the imaging optical path; the illumination module is used to compensate for the amount of light entering the imaging module.
[0021] In one embodiment, the imaging module is an ultraviolet camera and the objective lens module is an ultraviolet objective lens.
[0022] In one embodiment, the test head module includes a second objective lens, a second condenser, and an optical fiber. The light reflected from the sample is collected by the second objective lens, focused and transmitted to the receiving end face of one end of the optical fiber via the second condenser, and the other end of the optical fiber is connected to the second input end. The optical signal is transmitted to the test instrument body via the optical fiber.
[0023] In one embodiment, the loading assembly has a three-axis drive module, under which the loaded sample can move in three mutually perpendicular axes.
[0024] In one embodiment, the main axis of the objective lens module is set perpendicular to the sample surface, and the angle of inclination of the main axis of the test head module relative to the main axis of the objective lens module is in the range of 30-60°.
[0025] This application has at least the following beneficial effects:
[0026] In this application, the high-Al content AlGaN material with inverted light and heavy hole bands exhibits fluorescence emission perpendicular to the excitation light direction when the surface of the crystal along the c-axis is excited. Based on the characteristic that fluorescence propagates laterally along the crystal surface while very little fluorescence is emitted from the front, this application uses a test head module whose main axis is tilted relative to the objective lens module. The test head module and objective lens module collect fluorescence signals emitted from different directions on the sample surface to obtain the fluorescence signal of the high-Al content AlGaN material. Attached Figure Description
[0027] Figure 1 This is a three-dimensional structural diagram of a test system provided in an embodiment of this application.
[0028] Figure 2 This is a schematic diagram of the internal structure of a test system provided in an embodiment of this application.
[0029] Figure label:
[0030] 10. Display components;
[0031] 11. Imaging module; 12. Illumination module; 13. Objective lens module;
[0032] 20. Light processing components;
[0033] 21. Coupling module; 22. Optical path module; 23. Switching module; 24. Excitation light module;
[0034] 211. Coupled optical path;
[0035] 221. Optical filter; 222. Focusing element;
[0036] 30. Test components;
[0037] 31. Tester body; 32. Test head module;
[0038] 311. First input terminal; 312. Second input terminal;
[0039] 40. Material loading assembly;
[0040] 50. Sample. Detailed Implementation
[0041] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.
[0042] In the description of this application, it should be understood that if terms such as "length", "width", "thickness", "upper", "lower", "vertical", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.
[0043] Furthermore, where the terms "first," "second," and "third" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first," "second," and "third" may explicitly or implicitly include at least one of those features. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0044] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0045] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0046] It should be noted that if an element is referred to as being "fixed to," "set on," or "contained on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.
[0047] The embodiments of this application are described in detail below with reference to the accompanying drawings.
[0048] Reference Figure 1 , 2 As shown in some embodiments of this application, a confocal fluorescence spectroscopy testing system is provided, including: a display component 10, a light processing component 20, a testing component 30, and a material carrier component 40. Specifically, in this solution, the material carrier component 40 is used to load a sample 50. The display component 10 is used to image the sample 50, and has a built-in imaging optical path. One end of the display component 10 has an objective lens module 13, which is positioned close to the sample 50 on the material carrier component 40. The light processing component 20 is used to process the fluorescence signal, mainly filtering out the fluorescence signal from the light signal. The light processing component 20 has a detection optical path, one end of which is guided to the objective lens module 13.
[0049] The testing component 30 obtains the fluorescence spectral characteristics of the sample 50 based on the fluorescence signal. The testing component 30 includes a testing instrument body 31 and a testing head module 32. The testing instrument body 31 has a first input terminal 311 and a second input terminal 312. The other end of the detection optical path is directed to the first input terminal 311. The testing head module 32 is communicatively connected to the second input terminal 312. The testing head module 32 is used to detect the sample 50 on the material carrier component 40.
[0050] More specifically, in this scheme, the main axis of the test head module 32 is tilted relative to the main axis of the objective lens module 13, and the focal point of the objective lens module 13 and the focal point of the test head module 32 are at the same point.
[0051] For sample 50, which is an AlGaN material with a high Al content (Al content ≥ 50%), the light and heavy hole bands of sample 50 often reverse. When the sample 50 is excited from the front, the emission direction of fluorescence is perpendicular to the direction of the excitation light, meaning that the fluorescence propagates laterally along the crystal surface, while very little fluorescence is emitted from the front. Specifically, the front excitation of sample 50 involves projecting excitation light perpendicular to the test surface of sample 50, focusing the excitation light onto the sample 50 to form a spot, and then exciting the sample 50 to produce fluorescence or photocurrent.
[0052] Since this scheme includes a test head module 32 and an objective lens module 13, and the test head module 32 and the objective lens module 13 are arranged at different angles, when the objective lens module 13 projects excitation light, the fluorescence propagating laterally along the crystal surface can be collected by the test head module 32, so as to obtain the fluorescence spectral characteristics of sample 50 based on the fluorescence signal collected by the test head module 32.
[0053] Furthermore, the beam path shared by the imaging and detection optical paths, i.e., the imaging and detection optical paths intersect at a point, and then the intersecting imaging and detection optical paths are conducted on the same optical path, ultimately leading to the objective lens module 13; a switching module 22 is provided at the intersection of the imaging and detection optical paths, which is used to control the switching between imaging and fluorescence spectroscopy testing functions. The switching module 22 is located close to the objective lens module 13. In this scheme, the optical path between the switching module 22 and the objective lens module 13 is a shared optical path.
[0054] In this scheme, the switching module 22 has a built-in motion unit, and the switching module 22 can switch between a first position and a second position. At any given time, the switching module 22 is in one and only one position, either the first position or the second position. Specifically, the logic for controlling the switching of the switching module 22 between imaging and fluorescence spectroscopy testing functions is as follows:
[0055] When the switching module 22 moves to the first position, the imaging optical path is in the open state and the detection optical path is cut off. Cutting off the detection optical path can block the path of the beam on the detection optical path to the common optical path.
[0056] When the switching module 22 moves to the second position, the detection optical path is in the open state, and the imaging optical path is cut off. Cutting off the imaging optical path can block the path of the beam on the imaging optical path to the common optical path.
[0057] In some embodiments of this application, the optical processing component 20 includes an optical path module 22, which has a built-in filter 221 and a focusing plate 222. The filter 221 and the focusing plate 222 are located on the detection optical path, such that at least a portion of the detection optical path is located within the optical path module 22.
[0058] Meanwhile, the light processing assembly 20 also includes an excitation light module 24, which is positioned close to the optical path module 22. The excitation light module 24 is used to provide excitation light to excite the fluorescence of the sample 50. The excitation light emitted by the excitation light module 24 is guided by a filter 221 and transmitted through the detection optical path to the objective lens module 13, where it is projected and focused onto the sample 50 loaded in the material carrier assembly 40.
[0059] For example, the excitation module 24 can generate deep ultraviolet laser (typically 195 nm). The deep ultraviolet laser is focused into a micrometer-sized spot on the surface of the sample 50 by the objective lens module 13, which can greatly improve the excitation power density and obtain a stronger fluorescence signal. In addition, the filter 221 can filter the laser to allow fluorescence to pass through. The filter 221 can separate the fluorescence in the 235-550 nm range and allow it to enter the test assembly 30.
[0060] Furthermore, the detection optical path includes a coupling optical path 211. A coupling module 21 is provided between the optical path module 22 and the switching module 22 within the display component 10. The coupling optical path 211 is built into the coupling module 21, and light is transmitted between the filter 221 and the switching module 22 via the coupling optical path 211. The coupling optical path 211 can change the light propagation path to ensure that the optical paths after the imaging optical path and the detection optical path intersect are on the same straight line.
[0061] Furthermore, the display component 10 includes an imaging module 11 and an illumination module 12, with the imaging module 11 and the objective lens module 13 located at opposite ends of the imaging optical path; the illumination module 12 is used to compensate for the amount of light entering the imaging module 11.
[0062] Specifically, the imaging module 11 is an ultraviolet camera, and the objective lens module 13 is an ultraviolet objective lens. The ultraviolet laser generated by the excitation light module 24 can pass through the ultraviolet objective lens module 13, and at the same time, it can also perform microscopic imaging of the surface of the sample 50 through the ultraviolet imaging module 11.
[0063] In some embodiments of this application, the loading assembly 40 has a three-axis drive module, under which the loaded sample 50 can move in three mutually perpendicular axes. In order to focus the sample 50, the three-axis drive module moves the sample 50 in the Z-axis direction, which can focus the sample 50, and moves the sample 50 in the X and Y-axis directions, which can select a small area of the sample 50.
[0064] In some embodiments of this application, the main axis of the objective lens module 13 is arranged perpendicular to the surface of the sample 50, and the angle of inclination of the main axis of the test head module 32 relative to the main axis of the objective lens module 13 is in the range of 30-60°.
[0065] The test head module 32 is communicatively connected to the second input terminal 312, including: the test head module 32 includes a second objective lens, a second condenser and an optical fiber. The light reflected by the sample 50 is collected by the second objective lens, focused and transmitted to the receiving end face of one end of the optical fiber through the second condenser, and the other end of the optical fiber is connected to the second input terminal 312. The optical signal is transmitted to the test instrument body 31 through the optical fiber.
[0066] For the emission wavelength of AlN (200-210nm), there is no suitable filter to filter out the laser. Also, due to the inversion of the light and heavy hole bands, AlN emits fluorescence from the side. In this scheme, the fluorescence (200-550nm) emitted from the side of the sample 50 is collected by a second objective lens tilted at 60°. The fluorescence collected by the second objective lens is focused by the second condenser and then transmitted to the test instrument body 31 through the second input terminal 312 via optical fiber for collection and measurement.
[0067] Furthermore, a time-resolved single-photon module is also integrated within the test component 30. The fluorescence signal intensity is obtained by the fluorescence signal entering the test component 30, the fluorescence spectrum is obtained by gradually scanning the grating, and the fluorescence lifetime of the spectrum is obtained by the time-resolved single-photon module.
[0068] The above embodiments are used to further illustrate this application, but do not limit this application to these specific implementations. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be understood as falling within the protection scope of this application.
Claims
1. A confocal fluorescence spectroscopy testing system, characterized in that, include: A material carrier assembly (40) on which a sample (50) is loaded; The display component (10) has an imaging optical path built in, and an objective lens module (13) is provided at one end of the display component (10). The objective lens module (13) is positioned close to the sample (50) on the material carrier component (40). An optical processing component (20) has a detection optical path, one end of which is guided to the objective lens module (13). The test component (30) includes a tester body (31) and a test head module (32). The tester body (31) has a first input terminal (311) and a second input terminal (312). The other end of the detection optical path is directed to the first input terminal (311). The test head module (32) is communicatively connected to the second input terminal (312). The test head module (32) is used to test the sample (50) on the material carrier assembly (40); The main axis of the test head module (32) is inclined relative to the main axis of the objective lens module (13), and the focal point of the objective lens module (13) and the focal point of the test head module (32) are at the same point.
2. The confocal fluorescence spectroscopy testing system according to claim 1, characterized in that, The beam path shared by the imaging optical path and the detection optical path; A switching module (22) is provided at the intersection of the imaging optical path and the detection optical path, and the switching module (22) is located close to the objective lens module (13).
3. The confocal fluorescence spectroscopy testing system according to claim 2, characterized in that, The switching module (22) has a built-in motion unit and can switch between a first position and a second position; When the switching module (22) moves to the first position, the imaging optical path is in the open state and the detection optical path is cut off; When the switching module (22) moves to the second position, the detection optical path is in the open state and the imaging optical path is cut off.
4. The confocal fluorescence spectroscopy testing system according to claim 2, characterized in that, The optical processing component (20) includes an optical path module (22), which has a built-in filter (221) and a focusing plate (222); the filter (221) and the focusing plate (222) are located on the detection optical path; The light processing component (20) further includes an excitation light module (24), which is located close to the optical path module (22). The excitation light emitted by the excitation light module (24) is guided to the filter (221) and transmitted to the objective lens module (13) through the detection optical path. The objective lens module (13) projects and focuses the light onto the sample (50) loaded on the material carrier component (40).
5. The confocal fluorescence spectroscopy testing system according to claim 4, characterized in that, The detection optical path includes a coupling optical path (211); A coupling module (21) is provided between the optical path module (22) and the switching module (22) in the display component (10). The coupling optical path (211) is built into the coupling module (21) and transmits light between the filter (221) and the switching module (22) via the coupling optical path (211).
6. The confocal fluorescence spectroscopy testing system according to any one of claims 1-5, characterized in that, The display component (10) includes an imaging module (11) and an illumination module (12), wherein the imaging module (11) and the objective lens module (13) are respectively disposed at both ends of the imaging optical path; the illumination module (12) is used to compensate for the amount of light entering the imaging module (11).
7. The confocal fluorescence spectroscopy testing system according to claim 6, characterized in that, The imaging module (11) is an ultraviolet camera, and the objective lens module (13) is an ultraviolet objective lens.
8. The confocal fluorescence spectroscopy testing system according to any one of claims 1-5, characterized in that, The test head module (32) includes a second objective lens, a second condenser, and an optical fiber. The light reflected by the sample (50) is collected by the second objective lens, focused and transmitted to the receiving end face of one end of the optical fiber via the second condenser, and the other end of the optical fiber is connected to the second input end (312). The optical signal is transmitted to the test instrument body (31) via the optical fiber.
9. The confocal fluorescence spectroscopy testing system according to any one of claims 1-5, characterized in that, The loading assembly (40) has a three-axis drive module, under the drive of which the loaded sample (50) can move in three mutually perpendicular axes.
10. The confocal fluorescence spectroscopy testing system according to any one of claims 1-5, characterized in that, The main axis of the objective lens module (13) is set perpendicular to the surface of the sample (50), and the angle of inclination of the main axis of the test head module (32) relative to the main axis of the objective lens module (13) is in the range of 30-60°.