X-ray diffraction spectrum calibration method, device, electronic equipment and storage medium

Abstract

The present application provides a calibration method, device, electronic device and storage medium for an X-ray diffraction spectrum, which are applied to an X-ray diffractometer. The calibration method includes: obtaining the plane angle, sample lattice spacing, sample diffraction order, reference diffraction peak pixel coordinates and measured diffraction peak pixel coordinates of a sample to be tested, as well as the angular resolution of a preset complex light source and the wavelength corresponding to a characteristic peak; determining the reference angle corresponding to the reference diffraction peak pixel coordinates based on the plane angle, sample lattice spacing, sample diffraction order and the wavelength corresponding to any characteristic peak; determining the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested based on the reference angle, reference diffraction peak pixel coordinates, measured diffraction peak pixel coordinates and angular resolution; reducing the complexity of data acquisition and data processing, improving the angular scale accuracy of the X-ray diffraction spectrum, and thereby improving the accuracy and precision of the parameters of the sample to be tested.

Description

Technical Field

[0001] The present application belongs to the field of X-ray diffraction technology, and in particular relates to a calibration method, device, electronic equipment and storage medium for an X-ray diffraction spectrum. Background Art

[0002] X-ray diffraction (XRD) is an X-ray method used to analyze crystal structure. When X-rays pass through the sample to be tested, they interact with the atoms in the sample to be tested to produce diffraction lines, forming an X-ray diffraction spectrum. By measuring and analyzing the X-ray diffraction spectrum, the crystal structure, lattice parameters, crystal orientation, crystal purity and other information of the sample to be tested can be determined.

[0003] At present, the calibration method of the X-ray diffraction spectrum of the monochromatic X-ray light source needs to determine the correspondence between the pixel coordinates and angles of the X-ray diffractometer through the diffraction peaks of multiple crystal plane diffraction spectra of the sample to be tested, and then convert the pixel coordinates of the X-ray diffractometer into angles, which increases the complexity of data acquisition and reduces the angular scale accuracy of the X-ray diffraction spectrum.

[0004] The prior art has the problem that the calibration method of the X-ray diffraction spectrum of the monochromatic X-ray light source increases the complexity of data acquisition and reduces the angle scale accuracy of the X-ray diffraction spectrum. Summary of the invention

[0005] The embodiments of the present application provide a calibration method, device, electronic device and storage medium for X-ray diffraction, which can solve the problem that the calibration method of the X-ray diffraction spectrum of a monochromatic X-ray light source increases the complexity of data acquisition and reduces the angular scale accuracy of the X-ray diffraction spectrum.

[0006] In a first aspect, an embodiment of the present application provides a method for calibrating an X-ray diffraction spectrum, which is applied to an X-ray diffractometer, comprising:

[0007] Obtaining the plane angle of the sample to be tested, the sample lattice spacing, the sample diffraction order, the reference diffraction peak pixel coordinates and the measured diffraction peak pixel coordinates, as well as the angular resolution of the preset polychromatic light source and the wavelength corresponding to the characteristic peak, wherein the angular resolution is the angle value corresponding to any pixel of the preset polychromatic light source in the X-ray diffraction spectrum of the calibration sample, the preset polychromatic light source includes at least 2 of the characteristic peaks, and the plane angle is the angle between the measured crystal plane of the sample to be tested and the horizontal direction;

[0008] Determine a reference angle corresponding to the pixel coordinates of the reference diffraction peak based on the plane angle, the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any of the characteristic peaks;

[0009] Based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution, a calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be measured is determined.

[0010] In one embodiment, each of the characteristic peaks includes a first characteristic peak and a second characteristic peak;

[0011] The obtaining of the angular resolution comprises:

[0012] Acquire a first pixel coordinate corresponding to the first characteristic peak and a second pixel coordinate corresponding to the second characteristic peak of the X-ray diffraction spectrum of the preset polychromatic light source in the calibration sample, as well as a first diffraction angle corresponding to the first characteristic peak and a second diffraction angle corresponding to the second characteristic peak;

[0013] The angular resolution is determined by an angular resolution calculation formula based on the first diffraction angle, the second diffraction angle, the first pixel coordinates, and the second pixel coordinates.

[0014] In one embodiment, the angle resolution calculation formula is:

[0015]

[0016] Where RES is the angular resolution;

[0017] θ 1 is the first diffraction angle; θ 2 is the second diffraction angle;

[0018] P 1 is the first pixel coordinate; 2 is the second pixel coordinate.

[0019] In one embodiment, the sample diffraction order is the diffraction order corresponding to the crystal plane diffraction spectrum of the test crystal plane of the sample to be tested;

[0020] The step of determining the reference angle corresponding to the pixel coordinates of the reference diffraction peak based on the plane angle, the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any of the characteristic peaks comprises:

[0021] Determine the diffraction angle corresponding to any of the characteristic peaks based on the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any of the characteristic peaks;

[0022] Based on the diffraction angle corresponding to any of the characteristic peaks and the plane angle, a reference angle corresponding to the pixel coordinates of the reference diffraction peak is determined.

[0023] In one embodiment, determining the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution includes:

[0024] Based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution, a calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be measured is determined by a first calibration angle value calculation formula.

[0025] In one embodiment, the first calibration angle value calculation formula is:

[0026] θ i =θ ref +(P i -P ref )×RES

[0027] Among them, θ i is the calibration angle value corresponding to any pixel i;

[0028] θ ref is the reference angle; RES is the angle resolution;

[0029] P i is the pixel coordinate of the measured diffraction peak; ref is the pixel coordinate of the reference diffraction peak.

[0030] In one embodiment, the X-ray diffractometer includes a goniometer;

[0031] The step of determining a calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angle resolution further includes:

[0032] Based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates, the angular resolution and the compensation amount, a calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested is determined, wherein the compensation amount is the difference between the reference angle and the nominal angle, and the nominal angle is the angle of rotation of the goniometer corresponding to when the maximum intensity of the characteristic peak of the X-ray diffraction spectrum of the sample to be tested is determined by scanning.

[0033] In a second aspect, an embodiment of the present application provides a calibration device for an X-ray diffraction spectrum, which is applied to an X-ray diffractometer, comprising:

[0034] An acquisition module, used to acquire the plane angle of the sample to be tested, the sample lattice spacing, the sample diffraction order, the reference diffraction peak pixel coordinates and the measured diffraction peak pixel coordinates, as well as the angular resolution of a preset polychromatic light source and the wavelength corresponding to the characteristic peak, wherein the angular resolution is the angle value corresponding to any pixel of the preset polychromatic light source in the X-ray diffraction spectrum of the calibration sample, the preset polychromatic light source includes at least 2 of the characteristic peaks, and the plane angle is the angle between the measured crystal plane of the sample to be tested and the horizontal direction;

[0035] A first determination module is used to determine a reference angle corresponding to the pixel coordinates of the reference diffraction peak based on the plane angle, the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any of the characteristic peaks;

[0036] The second determination module is used to determine the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution.

[0037] In a third aspect, an embodiment of the present application provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, it implements a method as described in any one of the contents of the first aspect above.

[0038] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method as described in any one of the contents of the first aspect above is implemented.

[0039] In a fifth aspect, an embodiment of the present application provides a computer program product. When the computer program product is run on an electronic device, the electronic device executes any one of the methods described in the first aspect above.

[0040] It can be understood that the beneficial effects of the second to fifth aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here.

[0041] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0042] The X-ray diffraction spectrum calibration method of the present application is applied to an X-ray diffractometer. Compared with the X-ray diffraction spectrum calibration method of the prior art using a monochromatic X-ray light source, which increases the complexity of data acquisition and reduces the angular scale accuracy of the X-ray diffraction spectrum, the X-ray diffraction spectrum calibration method of the present application increases the complexity of data acquisition and reduces the angular scale accuracy of the X-ray diffraction spectrum. Since a preset polychromatic light source including at least two characteristic peaks is adopted and only any crystal face of the sample to be tested is measured, based on the angular resolution of the preset polychromatic light source, the sample to be tested parameters, the reference X-ray diffraction peak of any crystal face of the sample to be tested and the measured X-ray diffraction peak of any crystal face, the sample to be tested is determined without measuring multiple crystal faces of the sample to be tested. The calibration angle value corresponding to any pixel of the X-ray diffraction spectrum is determined, which reduces the data processing amount of the calibration angle value, thereby reducing the complexity of data acquisition and data processing. Only the X-ray diffraction spectrum of one crystal plane of the sample to be tested is used to determine the calibration angle value corresponding to any pixel, avoiding multiple calibration angle values ​​corresponding to pixels of the X-ray diffraction spectrum of multiple crystal planes, thereby improving the angle scale accuracy of the X-ray diffraction spectrum, and further improving the accuracy and precision of parameters such as the crystal structure, lattice parameter, crystal orientation, crystal purity, strain, relaxation, doping concentration, film thickness, etc. of the sample to be tested. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0044] Figure 1 It is a schematic flow chart of a method for calibrating an X-ray diffraction spectrum provided in one embodiment of the present application;

[0045] Figure 2 is a schematic diagram of a process for obtaining angular resolution provided by an embodiment of the present application;

[0046] Figure 3 It is a schematic diagram of a one-dimensional X-ray diffraction spectrum of a measured crystal plane of single crystal silicon (004) provided in one embodiment of the present application;

[0047] Figure 4 It is a flow chart of determining a reference angle corresponding to a reference diffraction peak pixel coordinate based on a plane angle, a sample lattice spacing, a sample diffraction order, and a wavelength corresponding to any characteristic peak in S200 provided in an embodiment of the present application;

[0048] Figure 5 It is a schematic diagram of angle calibration of a crystal plane diffraction spectrum of a (004) measurement crystal plane of a semiconductor material with a single crystal silicon substrate and silicon germanium (SiGe) as an epitaxial layer provided by another embodiment of the present application;

[0049] Figure 6 is a schematic diagram of a flow chart for determining a compensation amount provided by another embodiment of the present application;

[0050] Figure 7 It is a schematic diagram of the structure of the X-ray diffraction spectrum calibration device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0051] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0052] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0053] It should also be understood that the term “and / or” used in the specification and appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0054] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0055] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0056] The X-ray diffraction spectrum of the sample to be tested is angle-calibrated (also called angle scale), that is, the pixel coordinates of the horizontal axis of the X-ray diffraction spectrum of the sample to be tested are converted into the horizontal axis with angle value, and the vertical axis is still the radiation energy intensity. The X-ray diffraction spectrum is also called the X-ray light intensity distribution curve, which is convenient for correlating the X-ray diffraction spectrum obtained by the X-ray diffractometer detecting the sample to be tested with the parameters such as the crystal structure of the sample to be tested, and then determining the various crystal parameters of the sample to be tested. For example, the X-ray diffraction spectrum of the sample to be tested after angle calibration can determine the lattice information of the sample to be tested corresponding to the diffraction spectrum by linking the position of the diffraction peak in the X-ray diffraction spectrum with the Bragg law, that is, determine the unit cell parameters of the sample to be tested, and the unit cell parameters include lattice constant, unit cell volume and lattice spacing, etc.; the X-ray diffraction spectrum of the sample to be tested after angle calibration is the basis of phase analysis, which can make the position of the diffraction peak accurately correspond to a specific crystal plane, so that in phase analysis, the diffraction spectrum related data of the standard reference sample with known crystal structure can be used to analyze the diffraction pattern of the unknown sample, so as to determine the crystal structure of the sample to be tested; after angle calibration, the X-ray diffraction spectrum of the sample to be tested can be used to determine the crystal structure of the sample to be tested. The X-ray diffraction spectrum of the sample to be tested is also used for comparison and calibration between different samples to be tested. By aligning the diffraction spectrum related data of different samples to be tested on the angle scale of the horizontal axis, the diffraction peak positions and relative intensities of different samples to be tested can be intuitively compared, which is helpful to determine the differences between multiple samples and calibrate and qualitatively analyze multiple samples. The angle scale is a key step in obtaining the structural information of the sample to be tested in X-ray measurement. By measuring the position and radiation intensity of the diffraction peak of the X-ray diffraction spectrum of the sample to be tested, the lattice parameters, unit cell symmetry, crystal plane index and structural defects of the crystal can be extracted from the X-ray diffraction spectrum.

[0057] At present, the calibration method of the X-ray diffraction spectrum of the monochromatic X-ray light source needs to determine the correspondence between the pixel coordinates and angles of the X-ray diffractometer through the diffraction peaks of multiple crystal plane diffraction spectra of the sample to be tested, and then convert the pixel coordinates of the X-ray diffractometer into angles, which increases the complexity of data acquisition and reduces the angular scale accuracy of the X-ray diffraction spectrum.

[0058] In view of the above problems, the calibration method of X-ray diffraction spectrum of the present application is applied to X-ray diffractometer, by obtaining the plane angle of the sample to be tested, the sample lattice spacing, the sample diffraction order, the reference diffraction peak pixel coordinates and the measured diffraction peak pixel coordinates, as well as the angular resolution of the preset polychromatic light source and the wavelength corresponding to the characteristic peak, wherein the angular resolution is the angle value corresponding to any pixel of the X-ray diffraction spectrum of the calibration sample of the preset polychromatic light source, the preset polychromatic light source includes at least 2 characteristic peaks, and the plane angle is the angle between the measured crystal plane of the sample to be tested and the horizontal direction; based on the plane angle, the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any characteristic peak, the reference angle corresponding to the reference diffraction peak pixel coordinates is determined; based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution, the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested is determined; compared with the calibration method of X-ray diffraction spectrum of the monochromatic X-ray light source in the prior art, the complexity of data acquisition is increased. Compared with the conventional method, a preset polychromatic light source including at least two characteristic peaks is adopted, and only any crystal plane of the sample to be tested is measured, and then based on the angular resolution of the preset polychromatic light source, the parameters of the sample to be tested, the reference X-ray diffraction peak of any crystal plane of the sample to be tested and the measured X-ray diffraction peak of any crystal plane, the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested is determined without measuring multiple crystal planes of the sample to be tested, thereby reducing the data processing amount of the calibration angle value, thereby reducing the complexity of data acquisition and data processing, and only using the X-ray diffraction spectrum of one crystal plane of the sample to be tested to determine the calibration angle value corresponding to any pixel avoids multiple calibration angle values ​​corresponding to pixels of the X-ray diffraction spectra of multiple crystal planes, thereby improving the angular scale accuracy of the X-ray diffraction spectrum, and then improving the accuracy and precision of parameters such as crystal structure, lattice parameter, crystal orientation, crystal purity, strain, relaxation, doping concentration, film thickness, etc. of the sample to be tested.

[0059] The technical solution of the present application is described below through specific embodiments.

[0060] First, as Figure 1 As shown, the embodiment of the present application provides a method for calibrating an X-ray diffraction spectrum, which is applied to an X-ray diffractometer, comprising:

[0061] S100, obtaining the plane angle of the sample to be tested, the sample lattice spacing, the sample diffraction order, the reference diffraction peak pixel coordinates and the measured diffraction peak pixel coordinates, as well as the angular resolution of the preset polychromatic light source and the wavelength corresponding to the characteristic peak.

[0062] In one embodiment, the angular resolution is the angle value corresponding to any pixel of the X-ray diffraction spectrum of the calibration sample of the preset polychromatic light source; the preset polychromatic light source includes at least two characteristic peaks, each characteristic peak includes a first characteristic peak and a second characteristic peak; the plane angle is the angle between the measured crystal plane of the sample to be measured and the horizontal direction; the sample diffraction order is the diffraction order corresponding to the crystal plane diffraction spectrum of the test crystal plane of the sample to be measured; the reference diffraction peak pixel coordinates are the pixel coordinates corresponding to the diffraction peak in the X-ray diffraction spectrum of the calibration sample determined by a fitting method.

[0063] In one embodiment, in an X-ray diffractometer, copper is used as an anode target material, and the X-ray light source of the preset polychromatic light source is copper Kα radiation. The Kα radiation line of copper includes a first characteristic peak of Kα1 and a second characteristic peak of Kα2. The wavelength corresponding to the first characteristic peak of Kα1 of copper is The wavelength of the second characteristic peak of copper Kα2 is These two characteristic peaks are very close and are usually regarded as a double peak in X-ray diffraction analysis, called copper Kα double peak. In most X-ray diffraction analyses in the prior art, the characteristic radiation wavelength of Kα1 is mainly used, that is, a monochromatic X-ray radiation source is used.

[0064] In one embodiment, the X-ray diffractometer includes a two-dimensional pixel detector, and the pixel resolution of each detector includes 512×512, 1024×1024, etc. When using the X-ray diffractometer to measure the sample to be measured, the incident angle of the preset polychromatic light source and the receiving angle of the two-dimensional pixel detector need to be adjusted to the diffraction angle that satisfies the Bragg law; the preset polychromatic light source is used to illuminate the measurement crystal plane of the sample to be measured, and the two-dimensional pixel detector collects the X-ray diffraction spectrum through the measurement crystal plane (for example, the hkl parallel crystal plane); the two-dimensional X-ray diffraction spectrum is converted into a one-dimensional X-ray diffraction spectrum by integration, and the ordinate of the one-dimensional X-ray diffraction spectrum at this time is the radiation intensity, and the abscissa is 0 to the maximum value of the pixel resolution, that is, the abscissa is the pixel coordinate.

[0065] In one embodiment, Figure 2 As shown, the angular resolution is obtained, including:

[0066] S110, obtaining a first pixel coordinate corresponding to a first characteristic peak and a second pixel coordinate corresponding to a second characteristic peak of an X-ray diffraction spectrum of a calibration sample of a preset polychromatic light source, as well as a first diffraction angle corresponding to the first characteristic peak and a second diffraction angle corresponding to the second characteristic peak.

[0067] In one embodiment, single crystal silicon is used as a calibration sample, and the angular resolution of any pixel in the X-ray diffraction spectrum of the calibration sample is obtained by irradiating the measurement crystal plane (for example, the 004 crystal plane) with copper Kα radiation of a preset polychromatic light source, where 004 represents the 004 crystal plane of single crystal silicon, thereby facilitating the measurement of samples of semiconductor materials based on single crystal silicon.

[0068] In one embodiment, after using a copper Kα radiation light source to irradiate the (004) measurement crystal plane to obtain an X-ray diffraction spectrum of the calibration sample, the first diffraction angle θ corresponding to the first characteristic peak is determined according to the Bragg calculation formula. 1 The second diffraction angle θ corresponding to the second characteristic peak 2 .

[0069] Understandably, the Bragg calculation is:

[0070] 2d hkl sinθ=nλ

[0071] Where n is the diffraction order; λ is the wavelength of the X-ray source (i.e. the wavelength corresponding to the characteristic peak);

[0072] d hkl is the lattice spacing corresponding to the (hkl) measurement crystal plane of the sample; θ is the diffraction angle corresponding to the (hkl) measurement crystal plane.

[0073] In one embodiment, after obtaining a one-dimensional X-ray diffraction spectrum of the calibration sample by irradiating the (004) measurement crystal plane with a copper Kα radiation light source, a first pixel coordinate corresponding to the first characteristic peak Kα1 and a second pixel coordinate corresponding to the second characteristic peak Kα2 are determined from the one-dimensional X-ray diffraction spectrum, such as Figure 3 As shown, Figure 3 Schematic diagram of the one-dimensional X-ray diffraction spectrum of the single crystal silicon (004) crystal plane. The horizontal axis is the pixel coordinates from 0 to 512, and the vertical axis is the radiation intensity. The diffraction peak with a larger radiation intensity in the figure comes from the first characteristic peak Kα1, and the diffraction peak with a smaller radiation intensity in the figure comes from the second characteristic peak Kα2. The first pixel coordinate P of the diffraction peak corresponding to the first characteristic peak 1 Around 240, the second pixel coordinate P of the diffraction peak corresponding to the second characteristic peak 2 Around 261.

[0074] S120, determining the angular resolution by using an angular resolution calculation formula based on the first diffraction angle, the second diffraction angle, the first pixel coordinates, and the second pixel coordinates.

[0075] In one embodiment, based on the first diffraction angle, the second diffraction angle, the first pixel coordinates and the second pixel coordinates, the angular resolution is determined by an angular resolution calculation formula, so as to facilitate the determination of the angular resolution of the calibration sample, and then the angular resolution of the calibration sample is used as a reference to calibrate the angle of the X-ray diffraction spectrum of the sample to be measured.

[0076] In one embodiment, the angular resolution is calculated as:

[0077]

[0078] Where RES is the angular resolution;

[0079] θ 1 is the first diffraction angle; θ 2 is the second diffraction angle;

[0080] P 1 is the first pixel coordinate; P 2 is the second pixel coordinate.

[0081] S200, determining a reference angle corresponding to a pixel coordinate of a reference diffraction peak based on a plane angle, a sample lattice spacing, a sample diffraction order, and a wavelength corresponding to any characteristic peak.

[0082] In one embodiment, based on the plane angle, sample lattice spacing, sample diffraction order and the wavelength corresponding to any characteristic peak, the reference angle corresponding to the reference diffraction peak pixel coordinates is determined, thereby reducing the error of the calibration angle of any pixel of the sample to be tested, thereby improving the accuracy and precision of the parameters of the sample to be tested.

[0083] In one embodiment, Figure 4 As shown, based on the plane angle, sample lattice spacing, sample diffraction order and the wavelength corresponding to any characteristic peak, the reference angle corresponding to the pixel coordinate of the reference diffraction peak is determined, including:

[0084] S210, determining the diffraction angle corresponding to any characteristic peak based on the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any characteristic peak.

[0085] In one embodiment, the sample to be tested is a semiconductor material with single crystal silicon as a substrate and silicon germanium (SiGe) as an epitaxial layer. A copper Kα radiation light source is used to irradiate the (004) measurement crystal plane of the silicon germanium epitaxial layer to obtain an X-ray diffraction spectrum of the (004) measurement crystal plane of the silicon germanium epitaxial layer. Based on the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any characteristic peak, the diffraction angle θ corresponding to any characteristic peak of the crystal plane diffraction spectrum of the (004) measurement crystal plane of the silicon germanium epitaxial layer is determined by a Bragg calculation formula. Bragg .

[0086] S220, determining a reference angle corresponding to a pixel coordinate of a reference diffraction peak based on a diffraction angle and a plane angle corresponding to any characteristic peak.

[0087] In one embodiment, since the plane angle is the angle between the measured crystal plane of the sample to be measured and the horizontal direction, the plane angle between the (004) measured crystal plane of the silicon germanium epitaxial layer and the horizontal direction is determined by a geometric method, and then based on the sum of the diffraction angle corresponding to any characteristic peak and the plane angle, the reference angle θ corresponding to the pixel coordinate of the reference diffraction peak is determined. ref ,Right now Among them, θ ref is the reference angle, θ Bragg is the diffraction angle, is the plane angle.

[0088] S300, determining a calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be measured based on a reference angle, a reference diffraction peak pixel coordinate, a measured diffraction peak pixel coordinate and an angle resolution.

[0089] In one embodiment, based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution, the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested is determined, thereby improving the accuracy and precision of the calibration angle value of the sample to be tested.

[0090] In one embodiment, based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution, determining the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested, including: based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution, determining the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested by a first calibration angle value calculation formula, wherein the reference diffraction peak pixel coordinates P i It is the pixel coordinates of the diffraction peaks of the X-ray diffraction spectrum of the calibration sample fitted by the Gaussian function or the Lorentz function; further, the pixel coordinates of the diffraction peaks of the X-ray diffraction spectrum of the calibration sample are the pixel coordinates of the two diffraction peaks with larger radiation intensity. For example, the calibration angle values ​​corresponding to the two diffraction peaks are weighted to determine the weighted calibration angle value, which further improves the accuracy and precision of the calibration angle value.

[0091] It should be noted that in the prior art, the monochromatic X-ray light source has only one diffraction peak for the X-ray diffraction spectrum of the same (hkl) crystal plane, which easily causes deviations in the calibrated angle value. The polychromatic X-ray light source includes at least two characteristic peaks, and there are multiple diffraction peaks for the X-ray diffraction spectrum of the same (hkl) crystal plane. Any two of the diffraction peaks are taken for angle calibration, which improves the accuracy and precision of the calibrated angle value.

[0092] In one embodiment, the first calibration angle value calculation formula is:

[0093] θ i =θ ref +(P i -P ref )×RES

[0094] Among them, θ i is the calibration angle value corresponding to any pixel i, where i is an integer;

[0095] θ ref is the reference angle; RES is the angle resolution;

[0096] P i is the pixel coordinate of the measured diffraction peak; P ref is the pixel coordinate of the reference diffraction peak.

[0097] In one embodiment, Figure 5 As shown, Figure 5 The figure is a schematic diagram of the angle calibration of the crystal plane diffraction spectrum of the (004) measurement crystal plane of the semiconductor material with single crystal silicon as the substrate and silicon germanium (SiGe) as the epitaxial layer, that is, the crystal plane diffraction spectrum with pixel coordinates as the horizontal axis is completely converted into angle values ​​as the horizontal axis, and the vertical axis is still the radiation intensity; the rightmost peak in the figure is the diffraction peak of the (004) measurement crystal plane of the silicon germanium (SiGe) epitaxial layer, the diffraction peak with larger radiation intensity among the two peaks on the left is the diffraction peak generated by the first characteristic peak Kα1, and the diffraction peak with smaller radiation intensity among the two peaks on the left is the diffraction peak generated by the second characteristic peak Kα2.

[0098] In one embodiment, the X-ray diffractometer includes a goniometer, which can perform angle calibration of a one-dimensional diffraction spectrum at any angle and any crystal plane of a sample to be measured according to the pixel detector angle given by the goniometer, thereby increasing the application scope of the X-ray diffraction spectrum calibration method.

[0099] In one embodiment, based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution, determining the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested also includes:

[0100] Based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates, the angular resolution and the compensation amount, the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be measured is determined.

[0101] In one embodiment, based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates, the angular resolution and the compensation amount, the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested is determined, including: based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates, the angular resolution and the compensation amount, the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested is determined by a second calibration angle value calculation formula.

[0102] In one embodiment, the second calibration angle value calculation formula is:

[0103] θ i =θ ref +(P i -P ref )×RES+Δω

[0104] Among them, θ i is the calibration angle value corresponding to any pixel i, where i is an integer;

[0105] θ ref is the reference angle; RES is the angle resolution; Δω is the compensation amount;

[0106] P i is the pixel coordinate of the measured diffraction peak; P ref is the pixel coordinate of the reference diffraction peak.

[0107] In one embodiment, the compensation amount is the difference between the reference angle and the nominal angle, and the nominal angle is the angle of rotation of the goniometer corresponding to the maximum intensity of the characteristic peak of the X-ray diffraction spectrum of the sample to be tested determined by scanning; Figure 6 As shown, determine the compensation amount, including:

[0108] S310, determining the diffraction angle corresponding to any characteristic peak based on the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any characteristic peak.

[0109] In one embodiment, the sample to be tested is a semiconductor material with single crystal silicon as a substrate and silicon germanium (SiGe) as an epitaxial layer. A copper Kα radiation light source is used to irradiate the (004) measurement crystal plane of the silicon germanium epitaxial layer to obtain an X-ray diffraction spectrum of the (004) measurement crystal plane of the silicon germanium epitaxial layer. Based on the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any characteristic peak, the diffraction angle θ corresponding to any characteristic peak of the crystal plane diffraction spectrum of the (004) measurement crystal plane of the silicon germanium epitaxial layer is determined by a Bragg calculation formula. Bragg .

[0110] S320, based on the diffraction angle corresponding to any characteristic peak and the plane angle, determine a reference angle corresponding to the pixel coordinate of the reference diffraction peak, where the reference angle includes a grazing incidence reference angle or a grazing exit reference angle.

[0111] In one embodiment, the grazing incidence reference angle Grazing emission reference angle Among them, θ ref1-ka1 is the grazing incidence reference angle corresponding to the first characteristic peak Kα1, θ ref2-ka1 is the grazing emission reference angle corresponding to the first characteristic peak Kα1, θ Bragg is the diffraction angle, is the plane angle.

[0112] S330, determining a compensation amount based on a difference between a reference angle and a nominal angle.

[0113] In one embodiment, the calculation formula for obtaining the compensation amount is: Δω=θ ref-ka1 -θ ka1 ; Among them, Δω is the compensation amount; θ ref-ka1 is the reference angle; θ ka1 is the nominal angle corresponding to the first characteristic peak Kα1.

[0114] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0115] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0116] The X-ray diffraction spectrum calibration method of the present application is applied to an X-ray diffractometer. Compared with the X-ray diffraction spectrum calibration method of the prior art using a monochromatic X-ray light source, which increases the complexity of data acquisition and reduces the angular scale accuracy of the X-ray diffraction spectrum, the X-ray diffraction spectrum calibration method of the present application increases the complexity of data acquisition and reduces the angular scale accuracy of the X-ray diffraction spectrum. Since a preset polychromatic light source including at least two characteristic peaks is adopted and only any crystal face of the sample to be tested is measured, based on the angular resolution of the preset polychromatic light source, the sample to be tested parameters, the reference X-ray diffraction peak of any crystal face of the sample to be tested and the measured X-ray diffraction peak of any crystal face, the sample to be tested is determined without measuring multiple crystal faces of the sample to be tested. The calibration angle value corresponding to any pixel of the X-ray diffraction spectrum is determined, which reduces the data processing amount of the calibration angle value, thereby reducing the complexity of data acquisition and data processing. Only the X-ray diffraction spectrum of one crystal plane of the sample to be tested is used to determine the calibration angle value corresponding to any pixel, avoiding multiple calibration angle values ​​corresponding to pixels of the X-ray diffraction spectrum of multiple crystal planes, thereby improving the angle scale accuracy of the X-ray diffraction spectrum, and further improving the accuracy and precision of parameters such as the crystal structure, lattice parameter, crystal orientation, crystal purity, strain, relaxation, doping concentration, film thickness, etc. of the sample to be tested.

[0117] Second, as Figure 7As shown, the embodiment of the present application provides an X-ray diffraction spectrum calibration device 100, which is applied to an X-ray diffractometer, including:

[0118] The acquisition module 110 is used to obtain the plane angle of the sample to be tested, the sample lattice spacing, the sample diffraction order, the reference diffraction peak pixel coordinates and the measured diffraction peak pixel coordinates, as well as the angular resolution of the preset polychromatic light source and the wavelength corresponding to the characteristic peak, wherein the angular resolution is the angle value corresponding to any pixel of the preset polychromatic light source in the X-ray diffraction spectrum of the calibrated sample, the preset polychromatic light source includes at least 2 characteristic peaks, and the plane angle is the angle between the measured crystal plane of the sample to be tested and the horizontal direction.

[0119] The first determination module 120 is used to determine the reference angle corresponding to the pixel coordinates of the reference diffraction peak based on the plane angle, the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any characteristic peak.

[0120] The second determination module 130 is used to determine the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be measured based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angle resolution.

[0121] In one embodiment, the acquisition module 110 is also used to perform: obtaining a first pixel coordinate corresponding to a first characteristic peak and a second pixel coordinate corresponding to a second characteristic peak of an X-ray diffraction spectrum of a preset polychromatic light source in a calibration sample, as well as a first diffraction angle corresponding to the first characteristic peak and a second diffraction angle corresponding to the second characteristic peak; based on the first diffraction angle, the second diffraction angle, the first pixel coordinate and the second pixel coordinate, determining the angular resolution by an angular resolution calculation formula.

[0122] In one embodiment, the first determination module 120 is also used to perform: determining the diffraction angle corresponding to any characteristic peak based on the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any characteristic peak; determining the reference angle corresponding to the pixel coordinates of the reference diffraction peak based on the diffraction angle corresponding to any characteristic peak and the plane angle.

[0123] In one embodiment, the second determination module 130 is also used to perform: determining the diffraction angle corresponding to any characteristic peak based on the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any characteristic peak; determining the reference angle corresponding to the pixel coordinates of the reference diffraction peak based on the diffraction angle and the plane angle corresponding to any characteristic peak, the reference angle including the grazing incidence reference angle or the grazing exit reference angle; determining the compensation amount based on the difference between the reference angle and the nominal angle.

[0124] It should be noted that the information interaction, execution process, etc. between the above-mentioned modules / units are based on the same concept as the method embodiment of the present application. Their specific functions and technical effects can be found in the method embodiment part and will not be repeated here.

[0125] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0126] In a third aspect, an embodiment of the present application provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, it implements a method as described in any one of the contents of the first aspect above.

[0127] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method as described in any one of the contents of the first aspect above is implemented.

[0128] In a fifth aspect, an embodiment of the present application provides a computer program product. When the computer program product is run on an electronic device, the electronic device executes any one of the methods described in the first aspect above.

[0129] It can be understood that the beneficial effects of the second to fifth aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here.

[0130] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the processes in the above-mentioned embodiment method, which can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned method embodiments when executed by a processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form, etc.

[0131] The computer-readable medium may include at least: any entity or device capable of carrying computer program codes to a camera / terminal device, a recording medium, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electric carrier signal, a telecommunication signal, and a software distribution medium. For example, a USB flash drive, a mobile hard disk, a magnetic disk, or an optical disk. In some jurisdictions, according to legislation and patent practice, a computer-readable medium cannot be an electric carrier signal or a telecommunication signal.

[0132] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0133] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0134] In the embodiments provided in the present application, it should be understood that the disclosed devices / network equipment and methods can be implemented in other ways. For example, the device / network equipment embodiments described above are merely schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0135] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0136] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for calibrating an X-ray diffraction spectrum, characterized in that: Applications in X-ray diffractometers include: Obtaining the plane angle of the sample to be tested, the sample lattice spacing, the sample diffraction order, the reference diffraction peak pixel coordinates and the measured diffraction peak pixel coordinates, as well as the angular resolution of the preset polychromatic light source and the wavelength corresponding to the characteristic peak, wherein the angular resolution is the angle value corresponding to any pixel of the preset polychromatic light source in the X-ray diffraction spectrum of the calibration sample, the preset polychromatic light source includes at least 2 of the characteristic peaks, and the plane angle is the angle between the measured crystal plane of the sample to be tested and the horizontal direction; Determine a reference angle corresponding to the pixel coordinates of the reference diffraction peak based on the plane angle, the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any of the characteristic peaks; Determining a calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution, comprising: determining a calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested by a first calibration angle value calculation formula based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution, wherein the first calibration angle value calculation formula is: in, For any pixel i The corresponding calibration angle value; is the reference angle; is the angular resolution; is the pixel coordinate of the measured diffraction peak; is the pixel coordinate of the reference diffraction peak.

2. The method according to claim 1, characterized in that Each of the characteristic peaks includes a first characteristic peak and a second characteristic peak; The obtaining of the angular resolution comprises: Acquire a first pixel coordinate corresponding to the first characteristic peak and a second pixel coordinate corresponding to the second characteristic peak of the X-ray diffraction spectrum of the preset polychromatic light source in the calibration sample, as well as a first diffraction angle corresponding to the first characteristic peak and a second diffraction angle corresponding to the second characteristic peak; The angular resolution is determined by an angular resolution calculation formula based on the first diffraction angle, the second diffraction angle, the first pixel coordinates, and the second pixel coordinates.

3. The method according to claim 2, characterized in that The angular resolution calculation formula is: in, is the angular resolution; is the first diffraction angle; is the second diffraction angle; is the first pixel coordinate; is the second pixel coordinate.

4. The method according to claim 1, characterized in that The sample diffraction order is the diffraction order corresponding to the crystal plane diffraction spectrum of the test crystal plane of the sample to be tested; The step of determining the reference angle corresponding to the pixel coordinates of the reference diffraction peak based on the plane angle, the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any of the characteristic peaks comprises: Determine the diffraction angle corresponding to any of the characteristic peaks based on the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any of the characteristic peaks; Based on the diffraction angle corresponding to any of the characteristic peaks and the plane angle, a reference angle corresponding to the pixel coordinates of the reference diffraction peak is determined.

5. The method according to claim 1, characterized in that The X-ray diffractometer includes a goniometer; The step of determining a calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angle resolution further includes: Based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates, the angular resolution and the compensation amount, a calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested is determined, wherein the compensation amount is the difference between the reference angle and the nominal angle, and the nominal angle is the angle of rotation of the goniometer corresponding to when the maximum intensity of the characteristic peak of the X-ray diffraction spectrum of the sample to be tested is determined by scanning.

6. A calibration device for an X-ray diffraction spectrum, characterized in that: Applications in X-ray diffractometers include: An acquisition module, used to acquire the plane angle of the sample to be tested, the sample lattice spacing, the sample diffraction order, the reference diffraction peak pixel coordinates and the measured diffraction peak pixel coordinates, as well as the angular resolution of a preset polychromatic light source and the wavelength corresponding to the characteristic peak, wherein the angular resolution is the angle value corresponding to any pixel of the preset polychromatic light source in the X-ray diffraction spectrum of the calibration sample, the preset polychromatic light source includes at least 2 of the characteristic peaks, and the plane angle is the angle between the measured crystal plane of the sample to be tested and the horizontal direction; A first determination module is used to determine a reference angle corresponding to the pixel coordinates of the reference diffraction peak based on the plane angle, the sample lattice spacing, the sample diffraction order and the wavelength corresponding to any of the characteristic peaks; The second determination module is used to determine the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution, including: based on the reference angle, the reference diffraction peak pixel coordinates, the measured diffraction peak pixel coordinates and the angular resolution, determining the calibration angle value corresponding to any pixel of the X-ray diffraction spectrum of the sample to be tested by a first calibration angle value calculation formula, wherein the first calibration angle value calculation formula is: in, For any pixel i The corresponding calibration angle value; is the reference angle; is the angular resolution; is the pixel coordinate of the measured diffraction peak; is the pixel coordinate of the reference diffraction peak.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 5 is implemented.

8. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 5 is implemented.

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