WO2023097815A1

WO2023097815A1 - Raman spectrum-based particle detection and analysis system and method

Info

Publication number: WO2023097815A1
Application number: PCT/CN2021/140415
Authority: WO
Inventors: 罗先刚; 张涛; 高平; 岳伟生; 蒲明博; 李雄
Original assignee: 中国科学院光电技术研究所
Priority date: 2021-12-01
Filing date: 2021-12-22
Publication date: 2023-06-08
Also published as: CN114152547A

Abstract

A Raman spectrum-based particle detection and analysis system and method. The Raman spectrum-based particle detection and analysis system comprises: a light source assembly (2) used for generating a laser and splitting same; a Y-type optical fiber array (14), each Y-type optical fiber comprising an input end (502), a first output end (501), and a second output end (503), and the split laser being respectively input from the input end (502) of each Y-type optical fiber; a microlens array (13), each microlens group corresponding to the first output end (501) of each Y-type optical fiber, and being used for focusing the laser on the surface of a sample to be tested (12), collecting Raman signals excited by the laser, and respectively outputting same by means of the second output end (503) of each Y-type optical fiber; and a Raman spectrum assembly (3) used for receiving the Raman signals and obtaining particle components and position distribution on the surface of said sample (12). The system realizes high-throughput, rapid and real-time particle detection and component analysis on the surface of a large-size mask or wafer.

Description

Particle detection and analysis system and method based on Raman spectroscopy

This disclosure claims the priority of Chinese Patent Application No. 202111455052.4 filed on December 1, 2021, the entire contents of which are incorporated by reference in this disclosure.

technical field

The present disclosure relates to the technical field of optical analysis, in particular to a particle detection and analysis system and method based on Raman spectroscopy.

Background technique

Photomasks are a key process for making semiconductor devices and integrated circuit micro-pattern structures. With the development of integrated circuit design processes, the requirements for the quality of reticles are gradually becoming more stringent, and their quality directly affects the device yield and reliability. The stability and improvement of parameters such as reliability, device performance and service life. One of the most direct and important reasons that affect these performance parameters is the various defects and particles introduced in the entire photolithography process. During the production process of the mask plate, once the dust, particles and other pollutants in the environment fall on the mask plate, it will directly affect the pattern transfer of the integrated circuit pattern on the mask plate on the surface of the silicon wafer, resulting in fatal defects. Cause short circuit, open circuit, etc., directly affect the yield rate of integrated circuit products. The distribution of impurity particles on the wafer surface also needs to be strictly controlled to avoid chip loss due to ineffective etching.

In industrial applications, the control of hundreds of nanometers and micron-sized particles is extremely important. To solve the problem of particles on the surface of the reticle and wafer, the source and mechanism of the particles on the surface of the reticle and wafer must first be studied, which is very necessary to find out and solve the problem of particles on the surface of the reticle and wafer. Compositional analysis of the particles on the reticle and wafer surface will help to find out the source and mechanism of particle contamination, and provide important support for solving the problem of particle control and cleaning on the reticle and wafer surface.

At present, the particle detection technology at home and abroad mainly uses light scattering, image contrast, aerial image measurement and other technologies to realize the particle distribution and location on the surface of the mask or wafer, and the component analysis of the mask or wafer particles mainly uses the EDX of scanning electron microscope. (Energy Dispersive X-ray Detector) for fixed-point energy spectrum analysis can only be detected in a vacuum environment, lacking fast, large-area mask or wafer surface particle detection and analysis methods and equipment.

Therefore, high-efficiency, high-throughput, large-area particle detection and component analysis technology research has become an urgent need to solve the problem of particle control on reticles and wafers.

Contents of the invention

(1) Technical problems to be solved

In view of the above problems, the present disclosure provides a particle detection and analysis system and method based on Raman spectroscopy, which is used to solve technical problems such as high-efficiency, high-throughput, large-area particle detection and particle component analysis that are difficult to achieve with traditional particle detection technologies.

(2) Technical solutions

One aspect of the present disclosure provides a particle detection and analysis system based on Raman spectroscopy, including: a light source assembly for generating laser light and splitting the laser light; a Y-shaped optical fiber array, wherein each Y-shaped optical fiber includes an input end, a second One output end, the second output end, the split laser light is respectively input from the input end of each Y-shaped optical fiber; the microlens array, wherein each micro-lens group corresponds to the first output end of each Y-shaped optical fiber respectively, It is used to focus the laser on the surface of the sample to be detected, and collect the Raman signals excited by the laser, and output them through the second output end of each Y-shaped optical fiber; the Raman spectrum component is used to receive the Raman signal and obtain the Detect particle composition and location distribution on the sample surface.

Further, the Y-shaped optical fiber array and the microlens array are respectively distributed in an N*N array, where N is an integer; the first output end of each Y-shaped optical fiber is located at the focal plane of each microlens group.

Further, it also includes: a three-dimensional motion console, which is used to control the movement of the sample to be inspected, so that the laser light emitted from the microlens array performs area inspection on the partitions of the sample to be inspected sequentially.

Further, the three-dimensional motion console is used to control the sample to be tested to move in a zigzag in each area, and the zigzag is one of a horizontal zigzag, a vertical zigzag, an oblique zigzag or a combination thereof.

Further, the light source assembly includes: a laser; a power attenuation module for attenuating the power of the laser emitted by the laser; a laser splitter module for splitting the power-attenuated laser to the input end of each Y-shaped optical fiber.

Further, the emission wavelength of the laser is one of 266nm, 405nm, 488nm, 532nm, 633nm, 785nm, 830nm, 1064nm.

Further, the Raman spectrum component includes: a signal receiving module, used to receive the Raman signal output by the second output end of the Y-shaped optical fiber; a Raman spectrometer, used to convert the Raman signal into an electrical signal; a control analysis module, used to It is used to control the movement of the three-dimensional motion console and to generate the Raman spectrum of the sample to be tested according to the electrical signal, so as to obtain the particle position distribution and composition distribution on the surface of the sample to be tested.

Further, the sample to be tested is one of blank mask, layout mask and wafer.

Another aspect of the present disclosure provides a particle detection and analysis method based on Raman spectroscopy, including: a light source assembly generates laser light and splits the laser light; The input end is input, wherein each Y-shaped optical fiber includes an input end, a first output end, and a second output end; the microlens array focuses the laser light on the surface of the sample to be detected, and collects the Raman signals excited by the laser light, respectively passing through The second output end of each Y-shaped optical fiber is output, wherein each microlens group in the microlens array corresponds to the first output end of each Y-shaped optical fiber; the Raman spectrum component receives the Raman signal and obtains the sample to be detected Grain composition and location distribution on the surface.

Further, it also includes: the three-dimensional motion console controls the movement of the sample to be detected, so that the laser light emitted from the microlens array performs area detection on the samples to be detected sequentially.

Further, it also includes: the three-dimensional motion console controls the sample to be tested to move in a zigzag in each area, and the zigzag is one of a horizontal zigzag, a vertical zigzag, an oblique zigzag or a combination thereof; saving the collected The Raman spectrum is compared with the Raman spectrum of the particles preset in the database; move to the next area and repeat the steps of area detection until the detection is completed.

Further, it also includes: the control analysis module obtains the particle composition and position distribution on the surface of the sample to be tested according to the data detected in each area; the moving path of the area detection in the partitions is a horizontal zigzag, a vertical zigzag, and an oblique zigzag one or a combination of them.

(3) Beneficial effects

The particle detection and analysis system and method based on Raman spectroscopy provided by the present disclosure can quickly perform large-area particle detection and analysis by using a Y-shaped optical fiber array and a microlens array based on Raman spectroscopy signals; further combining two-dimensional scanning methods , realizing high-throughput, real-time detection of particle detection and particle composition analysis on surfaces such as large-scale masks or wafers.

Description of drawings

FIG. 1 schematically shows a schematic structural diagram of a particle detection and analysis system based on Raman spectroscopy in an embodiment of the present disclosure;

Fig. 2 schematically shows a distribution diagram of a Y-shaped fiber array and a microlens array according to an embodiment of the present disclosure;

Fig. 3 schematically shows a schematic diagram of the distribution of the microlens array and the spot after focusing the laser beam according to an embodiment of the present disclosure;

Fig. 4 schematically shows a schematic diagram of a dot matrix spot and its scanning path according to an embodiment of the present disclosure;

Fig. 5 schematically shows a schematic diagram of a scanning path for performing area detection on a sample to be detected according to an embodiment of the present disclosure;

FIG. 6 schematically shows a schematic diagram of an oblique zigzag scanning path according to an embodiment of the present disclosure;

Fig. 7 schematically shows a flow chart of a particle detection and analysis method based on Raman spectroscopy in an embodiment of the present disclosure;

FIG. 8 schematically shows the comparison analysis results of Raman spectra of particles measured on the surface of a reticle according to an embodiment of the present disclosure and a database.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

The terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting of the present disclosure. The terms "comprising", "comprising" and the like used herein indicate the presence of stated features, steps, operations and/or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.

All terms (including technical and scientific terms) used herein have the meaning commonly understood by one of ordinary skill in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted to have a meaning consistent with the context of this specification, and not be interpreted in an idealized or overly rigid manner.

An embodiment of the present disclosure provides a particle detection and analysis system based on Raman spectroscopy, please refer to FIG. 1 and FIG. 2 , including: a light source assembly 2, used to generate laser light and split the laser light; Y-shaped fiber array 14, Wherein each Y-shaped optical fiber comprises an input end 502, a first output end 501, and a second output end 503, and the laser light after beam splitting is respectively input from the input end 502 of each Y-shaped optical fiber; microlens array 13, wherein each microlens The lens group corresponds to the first output end 501 of each Y-shaped optical fiber, and is used to focus the laser light on the surface of the sample 12 to be detected, and collect the Raman signal excited by the laser, and pass through the second output end 501 of each Y-shaped optical fiber respectively. The output terminal 503 outputs; the Raman spectroscopic component 3 is used to receive the Raman signal and obtain the particle composition and position distribution on the surface of the sample 12 to be detected.

Figure 1 is a schematic diagram of the detailed structure of a particle detection and analysis system based on Raman spectroscopy, and Figure 2 is a schematic diagram of the distribution of a Y-shaped optical fiber array and a microlens array. The light source assembly 2 splits the laser light, and the split laser light is input from the input end 502 of each Y-shaped optical fiber (that is, the B end in FIG. (i.e. A terminal in FIG. 1 ) output, respectively through each microlens group in the microlens array 13 to focus incident on the surface of the sample 12 to be detected, the Raman signal excited by the surface passes through the microlens array 13, the first The first output terminal 501 and the second output terminal 503 (namely terminal C in FIG. 1 ) output; the Raman spectroscopy component 3 receives the Raman signal to obtain the particle composition and position distribution on the surface of the sample 12 to be detected.

In this disclosure, the use of Y-shaped optical fiber array and microlens array is beneficial to expand the detection area and realize rapid large-area particle detection; since the Raman signal can be excited and collected in an air environment, the system is used in a non-vacuum environment. It overcomes the condition limitation that traditional EDX can only be detected in a vacuum environment.

On the basis of the foregoing embodiments, the Y-shaped optical fiber array 14 and the microlens array 13 are distributed in an N*N array respectively, and N is an integer; the first output end 501 of each Y-shaped optical fiber is located at the focal point of each microlens group respectively. flat position.

Specifically, as shown in Figure 2, the Y-shaped optical fiber array 14 is distributed in an N*N array (N is an integer) by N ² single Y-shaped optical fibers, wherein the A-end center of each Y-shaped optical fiber is aligned with N*N A single microlens group in the microlens array, and the end face A is located at the focal plane of the single microlens group. Among them, the value of N is theoretically as large as possible, and it is actually related to the receiving range of the detector of the Raman spectrometer, and the value of N≤10 is possible.

The microlens array 13 is composed of N ² microlens groups in an N*N array distribution (N is an integer), and the function of a single microlens group is to collimate the light beam emitted from the A end of a single Y-shaped optical fiber and then focus it on the sample 12 to be tested. Another function of the single microlens group is to collect the Raman signal on the sample surface excited by the laser beam and send it to the A end of a single Y-shaped fiber. The Raman signal is collected by the A end of the single Y-shaped fiber and then passed through the single Y-shaped fiber The C-end of the optical fiber is output to the Raman spectrum component 3.

The Y-type fiber is a conventional Y-type fiber in the market. A single microlens group in the microlens array can include a plurality of raised microlenses but is not limited to a plurality of raised microlenses. Its function is to achieve the effect of beam collimation and focusing. The specific structure is shown as 504 in FIG. 2 Show.

On the basis of the above embodiments, it also includes: a three-dimensional motion console 11, which is used to control the movement of the sample 12 to be tested, so that the laser light emitted from the microlens array 13 performs area detection on the sample 12 to be tested sequentially.

The array scanning detection assembly 1 shown in FIG. 1 includes a Y-shaped optical fiber array 14 , a microlens array 13 , a sample to be detected 12 and a three-dimensional motion console 11 . The function of the three-dimensional motion console 11 is to carry the sample 12 to be tested, and the software controls the three-dimensional motion console 11 to move according to the designed displacement route, wherein the movement along the Z direction is used to fix the surface of the sample 12 to be tested in the Z direction The position is such that the focal plane of the laser beam after being focused by the microlens array 13 coincides with the surface of the sample 12 to be tested; the movement in the horizontal X/Y direction is used to detect each area according to the pre-designed scanning detection circuit.

On the basis of the above-mentioned embodiments, the three-dimensional motion console 11 is used to control the sample 12 to be tested to move in a zigzag in each area, and the zigzag can be one of a horizontal zigzag, a vertical zigzag, and an oblique zigzag or a combination thereof.

The surface of the sample 12 to be tested can be divided into M*M array areas, each area is quickly detected in turn, and the range of each area is determined by the range of the microlens array. The detection method is to perform zigzag movement scanning detection in each area first, and perform zigzag movement scanning detection between M*M array areas in the same way after each area is detected. The horizontal zigzag path is shown in Figure 4, and the oblique zigzag path is shown in Figure 6.

On the basis of the above-mentioned embodiments, the light source assembly 2 includes: a laser 23; a power attenuation module 22, which is used to attenuate the power of the laser emitted by the laser; a laser beam splitter module 21, which is used to split the power attenuated laser light into An input end 502 of a Y-shaped optical fiber.

The light source assembly 2 may include a laser 23, a power attenuation module 22, and a laser beam splitter module 21; the laser beam emitted from the laser 23 is attenuated by the power attenuation module 22, and the laser beam is split by the laser beam splitter module 21 and then focused on the Y-shaped optical fiber the B side. The power attenuation module 22 is used to adjust the emitted laser power, and the attenuation ratio can be controlled by the control analysis module 33 . Preferably, the number of laser beams split by the laser beam splitting module 21 corresponds to the number N ² of the Y-shaped fiber arrays 14 .

Based on the above embodiments, the emission wavelength of the laser 23 may be one of 266nm, 405nm, 488nm, 532nm, 633nm, 785nm, 830nm, 1064nm.

The emission wavelength of the laser 23 includes but is not limited to the common Raman excitation wavelength.

On the basis of the above-described embodiments, the Raman spectrum assembly 3 includes: a signal receiving module 31, used to receive the Raman signal output by the second output end 503 of the Y-shaped optical fiber; a Raman spectrometer 32, used to convert the Raman signal Generate an electrical signal; control the analysis module 33, used to control the movement of the three-dimensional motion console 11 and to generate the Raman spectrum of the sample to be tested according to the above electrical signal, and obtain the particle composition and position distribution on the surface of the sample to be tested.

The control analysis module 33 can include a computer and its host computer Raman data analysis unit, and the computer can be used to control the motion of the three-dimensional motion console 11, the attenuation ratio of the power attenuation module and store corresponding data, etc.; the host computer Raman data analysis unit It can be used to generate the Raman spectrum of the sample to be tested according to the electrical signal, and obtain the particle composition and position distribution on the surface of the sample to be tested.

Specifically, the Raman spectroscopy component 3 includes a signal receiving module 31, a Raman spectrometer 32, a computer and a Raman data analysis unit. The signal receiving module 31 is used to receive the Raman signal output by the Y-shaped optical fiber array 14, and the electrical signal output by the Raman spectrometer 32 is transmitted to the computer in the control analysis module 33 and its host computer Raman data analysis unit.

The Raman data analysis unit is used to generate the Raman spectrum of the sample to be tested, and compare and analyze the measured Raman spectrum with the Raman spectrum of each material component in the database to obtain the position of the sample corresponding to the measured Raman spectrum Particle composition; at the same time, all measured Raman spectral data are saved in a readable data format to the local disk of the computer, and the results of comparative analysis are systematically classified and counted. The functions of the control analysis module 33 may also include setting the detection range and detection method of the sample 12 to be detected, and controlling the displacement of the three-dimensional motion console 11 according to the set detection route.

On the basis of the above embodiments, the sample 12 to be inspected may be one of a blank mask, a layout mask, and a wafer.

The sample 12 to be tested can be a sample with a large area, such as a 6-inch blank mask, a 6-inch layout mask, a 6-inch wafer, an 8-inch wafer, a 12-inch wafer, and the like.

The present disclosure also provides a particle detection and analysis method based on Raman spectroscopy, please refer to FIG. 7 , including:

S1, the light source assembly 2 generates laser light and splits the laser light;

S2, the beam-splitting laser is respectively input from the input end 502 of each Y-shaped fiber in the Y-shaped fiber array 14, wherein each Y-shaped fiber includes an input end 502, a first output end 501, and a second output end 503;

S3, the microlens array 13 focuses the laser on the surface of the sample 12 to be detected, and collects the Raman signals excited by the laser, and outputs them through the second output end 503 of each Y-shaped optical fiber, wherein each of the microlens arrays 13 A microlens group corresponds to the first output end 501 of each Y-shaped optical fiber respectively;

S4, the Raman spectroscopic component 3 receives the Raman signal and obtains the particle composition and position distribution on the surface of the sample 12 to be detected.

Specifically, the laser light emitted by the laser 23 in the light source assembly 2 enters the laser beam splitting module 21 after being attenuated by the power attenuation module 22, and the laser beam enters the B end of the Y-shaped fiber array 14 after being split by the laser beam splitting module 21, and the Y-shaped fiber array The A end of 14 is connected to the microlens array 13; the laser beam after beam splitting is focused and incident on the sample 12 to be tested after being passed through the laser beam splitting module 21, the Y-shaped fiber array 14, and the microlens array 13, and the sample 12 to be tested is placed in a three-dimensional motion On the console 11; the Raman spectrum excited is collected into the Y-shaped fiber array 14 through the microlens array 13, and enters the Raman spectrometer 32 after being output by the C end of the Y-shaped fiber array 14 and the signal receiving module 31; the control analysis module 33 controls The sample 12 to be detected in the three-dimensional motion console 11 is moved, and the Raman spectrometer 32 is controlled to collect and save the Raman spectrum corresponding to the area. At the same time, the collected data is compared and analyzed in the database to obtain the particle position distribution on the surface of the sample to be detected, Real-time display of test results after component distribution.

On the basis of the above-mentioned embodiments, it also includes: the three-dimensional motion console 11 controls the movement of the sample 12 to be inspected, so that the laser light emitted from the microlens array 13 sequentially detects the regions of the sample 12 to be inspected.

The surface of the sample 12 to be tested can be divided into M*M array areas, each area is quickly detected in turn, and the range of each area is determined by the range of the microlens array. The sample 12 to be tested is moved by the three-dimensional motion console 11 for area scanning analysis without moving the light source component 2 and the array scanning detection component 1, which is beneficial to speed up the detection speed.

On the basis of the above embodiments, it also includes: the three-dimensional motion console 11 controls the sample 12 to be detected to move in a zigzag in each area, and the zigzag can be one of a horizontal zigzag, a vertical zigzag, and an oblique zigzag One or a combination thereof; save the collected Raman spectrum and compare it with the Raman spectrum of the preset particles in the database; then move to the next area and repeat the above-mentioned area detection steps until the detection is completed.

The detection method in each area may be zigzag scanning detection, which has been described in detail above and will not be repeated here. After the detection of the first region in the M*M array is completed, the sample 12 to be detected is then moved to detect the second region. The detection method of the M*M array can be the path shown in Figure 5, and each region is detected in turn until the entire waiting area is completed. Detection of sample 12. By means of two-dimensional scanning, the surface of the sample 12 to be tested can be quickly scanned to realize high-throughput and real-time particle analysis on large-sized surfaces.

On the basis of the above embodiments, it also includes: the Raman data analysis unit of the control analysis module 33 obtains the particle composition and position distribution on the surface of the sample 12 to be tested according to the data detected in each area; It can be one of horizontal zigzag, vertical zigzag, oblique zigzag or a combination thereof.

Further, the Raman data analysis unit generates the Raman spectrum of the surface particles of the sample 12 to be detected, and compares the measured Raman spectrum with the Raman spectrum of each material component in the database, and performs a systematic comparison of the results of the comparative analysis. Classify and count and generate a map to visually display the distribution of particle components.

The present disclosure provides a particle detection and analysis method based on Raman spectroscopy. Aiming at the lack of rapid and large-area particle component analysis in a non-vacuum environment in the prior art, based on Raman spectroscopy signals, microlens arrays, Y-shaped fiber arrays and The two-dimensional scanning method realizes high-throughput, fast and real-time detection of particle composition analysis and position distribution on the surface of large-scale masks or wafers. The present disclosure can further realize the intuitive display of the composition distribution map of all particulate matter on the surface of a large-scale mask or wafer and the proportion of each composition.

The present disclosure will be further described below through specific embodiments, taking the sample to be tested as a blank mask as an example.

Fig. 1 schematically shows a schematic structural diagram of a particle detection and analysis system based on Raman spectroscopy according to an embodiment of the present disclosure.

This embodiment provides a particle detection and analysis system based on Raman spectroscopy, including: a light source component 2 , an array scanning detection component 1 , and a Raman spectrum component 3 . The light source assembly 2 includes a laser 23, a power attenuation module 22, and a laser beam splitting module 21; the laser light emitted by the laser 23 is attenuated by the power attenuation module 22, and then split by the laser beam splitting module 21. The input end 502 of a Y-shaped optical fiber is input. The array scanning detection assembly 1 includes a Y-shaped optical fiber array 14, a microlens array 13, a sample to be detected 12, and a three-dimensional motion console 11; As shown in the figure on the left, the Y-shaped optical fiber consists of an input end 502 (B end), a first output end 501 (A end), and a second output end 503 (C end); the first output end 501 of the Y-shaped fiber array and the microlens The array 13 is distributed as shown in the figure on the right. Each microlens group corresponds to the first output end 501 of each Y-shaped optical fiber. Each microlens group is used to focus the laser light on the surface of the sample 12 to be tested and collect the The Raman signals excited by the laser are respectively output through the second output end 503 of each Y-shaped optical fiber. The Raman spectrum assembly 3 includes a signal receiving module 31, a Raman spectrometer 32 and a control analysis module 33; the signal receiving module 31 is used to receive the Raman signal output by the second output terminal 503, and the Raman spectrometer 32 is used to receive the Raman signal Converted into electrical signals; control analysis module 33, used to control the movement of the three-dimensional motion console 11 and used to generate the Raman spectrum of the sample 12 to be tested according to the aforementioned electrical signals, and obtain the particle position distribution and component distribution on the surface of the sample 12 to be tested. In this embodiment, the sample to be detected is a blank mask 402 .

Specifically, the laser light emitted by the laser 23 in the light source assembly 2 enters the laser beam splitting module 21 after passing through the power attenuation module 22, and the laser beam enters the B end of the Y-shaped fiber array 14 after being split by the laser beam splitting module 21, and the Y-shaped fiber array The A end of 14 is connected to the microlens array 13; the laser beam passes through the laser beam splitting module 21, the Y-shaped fiber array 14, and the microlens array 13, and then focuses and enters the sample 12 to be tested, and the sample 12 to be tested is placed on the three-dimensional motion console 11 The Raman spectrum of excitation enters the Y-type fiber array 14 through the microlens array 13 collection, and enters the Raman spectrometer 32 after the C end of the Y-type fiber array 14, the signal receiving module 31 output; The control analysis module 33 controls the three-dimensional motion console The sample 12 to be detected in 11 moves in a zigzag shape, and the Raman spectrometer 32 is controlled to collect and save the Raman spectrum corresponding to the area. At the same time, the collected data is compared and analyzed in the database, and the detection result is displayed in real time. The zigzag moving path in this embodiment is shown in FIG. 4 .

Referring to Figures 1 to 5, the basic process of using the particle detection and analysis system based on Raman spectroscopy and performing high-throughput particle composition analysis based on Raman spectroscopy is as follows:

(1) Turn on the power of the laser, the light spots after the laser beam passes through the Y-shaped fiber array 14 and the microlens array 13 are distributed in a dot matrix, and the laser beam 505 output from the A end of the Y-shaped fiber array passes through the microlens array 504 and then focuses. The distribution of the microlens array 13 and the spot after focusing the laser beam are shown in Figure 3, d is the distance between two adjacent lenses or two adjacent spots, the left side of Figure 3 is the distribution of the microlens array 201, and the right side of Figure 3 is the distribution of the spot 202 after the laser beam is focused.

(2) Fix a 6-inch square blank mask on the three-dimensional motion console 11, place the side length of the square mask in the same direction as the horizontal X/Y direction, and control the analysis module 33 to control the three-dimensional motion console 11 to move along the Z direction, The surface of the blank mask is located at the focal plane of the microlens array, and the side length of the mask is 152 mm.

(3) According to the size of the blank mask used in the horizontal X/Y direction, the control analysis module 33, as shown in FIG. In M=8), the initial detection position is set to be the first area 401 in the upper left corner of the blank mask; wherein the value of M adopts M=mask plate side length/(spot spacing d*N), and N is in this embodiment 5. The spot distance d is 3.8mm, and the value of d is generally above 3mm.

(4) Then the detection mode of the first area 401 is set, as shown in Figure 4, the dotted line frame is the boundary 303 of the first area 401 among the figure; The dot matrix light spot moves and scans successively according to the zigzag scanning path 302 at the initial position 301 Detection, the right figure is the end point detection position of the first area.

(5) The control analysis module 33 controls the movement of the three-dimensional motion console 11 so that the dot matrix spot moves sequentially at the initial position 301 along the zigzag scanning path 302 for scanning detection. First, when the array spot is at the initial position 301, the N*N array Raman signal is collected and a corresponding Raman spectrum is generated, and then the single-step distance D is moved laterally to the right (the single-step displacement distance D in the zigzag scanning path 302=spot spacing d/N, D in the present embodiment is 0.76mm), the Raman spectrum that collects is saved simultaneously in the moving process and is compared and analyzed with the database, and the N*N array Raman signal of this position is collected after moving the single-step distance D to stop. Generate the corresponding Raman spectrum; continue to move horizontally to the right by a single step distance D, repeat the previous steps, collect the N*N array Raman signal at the current position after each step and generate the corresponding Raman spectrum, and save the collected Raman spectrum at the same time Mann spectrum and comparative analysis with the database; from the initial position 301, move N steps horizontally to the right, then move down one step vertically, then move N steps horizontally in the reverse direction, then move down one step vertically, and cycle in turn, and finally a single zigzag scanning process A total of N steps are required to move vertically. Corresponding to FIG. 4 , the scanning in the small area is horizontal zigzag, and can also be vertical zigzag and oblique zigzag.

(6) After the detection of the first area is completed, move (N-1)*d horizontally from the end position of the first area to the right, move up d vertically to the next area, and proceed according to the zigzag scanning path 403 shown in Figure 5 The detection of other regions is followed in turn, and the step (5) is repeated for each region detection step. Similarly, the scanning of the entire area can also be in the shape of vertical zigzag and oblique zigzag, and the effect is also consistent. Thus, the above three scan modes for the small area and the three scan modes for the entire area can be randomly combined to form nine feasible scan combination modes, which is not limited in the present disclosure.

(7) Compare, classify and count all the collected Raman spectrum analysis data with the database. Figure 8 shows the comparison and analysis results of the particle Raman spectrum measured on the surface of the mask plate and the database. The composition of the particles can be seen from the comparison analysis results Mainly PVC lubricants and calcium carbonate, this result can provide important help in tracing and analyzing the source of particles.

The Raman spectrum-based particle detection and analysis system and method of the present disclosure are based on Raman spectrum signals, and use microlens arrays, Y-shaped fiber arrays, and two-dimensional scanning methods to achieve high-throughput, fast, and real-time large-scale mask or Particle detection and compositional analysis of surfaces such as wafers.

The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present disclosure in detail. It should be understood that the above descriptions are only specific embodiments of the present disclosure, and are not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included within the protection scope of the present disclosure.

Claims

A particle detection and analysis system based on Raman spectroscopy, characterized in that it includes:

A light source assembly (2), configured to generate laser light and split the laser light into beams;

Y-shaped optical fiber array (14), wherein each Y-shaped optical fiber includes an input end (502), a first output end (501), and a second output end (503), and the laser light after beam splitting is respectively transmitted from each Y-shaped optical fiber The input end (502) of the optical fiber is input;

A microlens array (13), wherein each microlens group corresponds to the first output end (501) of each Y-shaped optical fiber, and is used to focus the laser light on the surface of the sample to be detected (12), and Collect the Raman signals excited by the laser, and output them through the second output end (503) of each Y-shaped optical fiber;

A Raman spectroscopic component (3), configured to receive the Raman signal and obtain particle composition and position distribution on the surface of the sample to be detected (12).
The particle detection and analysis system based on Raman spectroscopy according to claim 1, wherein said Y-shaped optical fiber array (14) and microlens array (13) are distributed in N*N arrays respectively, and N is an integer; The first output end (501) of each Y-shaped optical fiber is respectively located at the focal plane position of each microlens group.
The particle detection and analysis system based on Raman spectroscopy according to claim 1, further comprising:

The three-dimensional motion console (11) is used to control the movement of the sample to be detected (12), so that the laser emitted from the microlens array (13) sequentially detects the regions of the sample to be detected (12).
The particle detection and analysis system based on Raman spectroscopy according to claim 3, wherein the three-dimensional motion console (11) is used to control the sample to be detected (12) to carry out Z in each of the regions. Zigzag movement, the zigzag is one of horizontal zigzag, vertical zigzag, oblique zigzag or a combination thereof.
The particle detection and analysis system based on Raman spectroscopy according to claim 1, wherein the light source assembly (2) comprises:

laser (23);

A power attenuation module (22), used to attenuate the power of the laser emitted by the laser;

A laser beam splitting module (21), configured to split the power-attenuated laser beam to the input end (502) of each Y-shaped optical fiber.
The particle detection and analysis system based on Raman spectroscopy according to claim 5, wherein the emission wavelength of the laser (23) is one of 266nm, 405nm, 488nm, 532nm, 633nm, 785nm, 830nm, 1064nm .
The particle detection and analysis system based on Raman spectroscopy according to claim 3, wherein the Raman spectroscopy component (3) comprises:

A signal receiving module (31), configured to receive the Raman signal output by the second output end (503) of the Y-shaped optical fiber;

Raman spectrometer (32), for converting the Raman signal into an electrical signal;

The control analysis module (33) is used to control the movement of the three-dimensional motion console (11) and is used to generate the Raman spectrum of the sample to be detected (12) according to the electrical signal, so as to obtain the sample to be detected (12) ) particle composition and location distribution on the surface.
The particle detection and analysis system based on Raman spectroscopy according to any one of claims 1 to 7, wherein the sample to be detected (12) is one of a blank mask, a layout mask, and a wafer .
A method for particle detection and analysis based on Raman spectroscopy, characterized in that it comprises:

The light source assembly (2) generates laser light and splits the laser light into beams;

The split laser light is input from the input end (502) of each Y-shaped optical fiber in the Y-shaped optical fiber array (14), wherein each Y-shaped optical fiber includes an input end (502), a first output end (501), a second output terminal (503);

The microlens array (13) focuses the laser light on the surface of the sample (12) to be detected, and collects the Raman signals excited by the laser light, and passes through the second output end (503) of each Y-shaped optical fiber respectively Output, wherein each microlens group in the microlens array (13) corresponds to the first output end (501) of each Y-shaped optical fiber;

The Raman spectroscopic component (3) receives the Raman signal and obtains the particle composition and position distribution on the surface of the sample to be detected (12).
The particle detection and analysis method based on Raman spectroscopy according to claim 9, further comprising:

The three-dimensional motion console (11) controls the movement of the sample to be detected (12), so that the laser light emitted from the microlens array (13) sequentially detects the regions of the sample to be detected (12).
The method for particle detection and analysis based on Raman spectroscopy according to claim 10, further comprising:

The three-dimensional motion console (11) controls the sample to be detected (12) to move in a zigzag in each of the regions, and the zigzag is one of a horizontal zigzag, a vertical zigzag, and an oblique zigzag. species or combinations thereof;

Save the collected Raman spectrum and compare it with the Raman spectrum of the particles preset in the database;

Move to the next area, and repeat the steps of area detection until the detection is completed.
The method for particle detection and analysis based on Raman spectroscopy according to claim 10 or 11, further comprising:

The control analysis module (33) obtains the particle composition and position distribution on the surface of the sample to be detected (12) according to the data detected in each area;

The moving path of the sub-area for area detection is one of a horizontal zigzag, a vertical zigzag, an oblique zigzag or a combination thereof.