Method for detecting metal impurity content in organic zirconium precursor

Abstract

This application relates to a method for detecting the content of metal impurities in organozzirconium precursors. First, the zirconium precursor sample to be tested is taken, digested with ultrapure hydrofluoric acid, and then diluted to obtain the test solution. Standard solutions containing 20 elements, including Li and Be, are prepared. The standard solutions are then added to the test solution to prepare a standard working curve solution. The standard curve and regression equation are obtained using ICP MS / MS. Finally, a blank solution is prepared and detected using ICP MS / MS. The content of metal impurity elements in the sample is calculated based on the regression equation. This application effectively reduces matrix interference by optimizing parameters such as carrier gas flow rate and RF power. Simultaneously, by utilizing energy discrimination, different collision reaction modes, and reaction gas and voltage conditions, interfering ions are selectively eliminated, improving detection sensitivity and enabling accurate detection of low-concentration samples. The use of hydrofluoric acid pretreatment ensures complete sample digestion, improving the accuracy of metal impurity detection results.

Description

Technical Field

[0001] This application belongs to the field of inductively coupled plasma tandem mass spectrometry detection technology, specifically relating to a method for detecting the content of metallic impurities in organozirconium precursors. Background Technology

[0002] Organic zirconium precursors are widely used in advanced ceramics, catalysts, optical materials and semiconductor manufacturing, and their purity directly determines the electrical, optical and structural properties of the final thin film material.

[0003] Sample pretreatment of organozirconium precursors is a crucial step in the entire detection process. These compounds generally exhibit high reactivity, volatility, flammability, and hydrolysis. The entire sampling and weighing process must be completed in a glove box under inert gas protection. For conventional organometallic precursors, high-purity concentrated nitric acid is commonly used for digestion. However, zirconium has a strong passivation effect, readily forming a dense, chemically stable oxide film on its surface. This oxide film effectively resists corrosion from various acids, making nitric acid-based digestion systems inefficient or even impossible. Therefore, introducing hydrofluoric acid becomes the necessary choice to break the zirconium passivation film, effectively complex zirconium ions, and achieve complete sample dissolution.

[0004] In the detection of metallic impurities, inductively coupled plasma mass spectrometry (ICP-MS) has become the mainstream technique for trace and ultra-trace element analysis due to its extremely high sensitivity, extremely low detection limit, wide dynamic linear range, and ability to analyze multiple elements simultaneously. For the detection of impurity elements in high-purity materials, ICP-MS demonstrates irreplaceable advantages. However, standard conventional ICP-MS analytical methods exhibit significant limitations when dealing with complex zirconium matrices.

[0005] Traditional ICP-MS instruments, especially standard models equipped with a single quadrupole and a collision / reaction cell, face interference from polyatomic ions, oxides, double-charged ions, hydrides, and isotopes when determining trace impurities in zirconium-based samples. Among these, polyatomic ion interference generated by the zirconium matrix is ​​the most challenging problem. Zirconium has five stable isotopes: 90 Zr、 91 Zr、 92 Zr、 94 Zr、 96 In plasma, zirconium ions readily combine with elements such as oxygen, argon, and hydrogen to form a series of polyatomic ions. The mass numbers of these polyatomic ions overlap with the isotopes of the target impurity elements, generating false signals. Furthermore, the determination of elements such as ruthenium, tin, and antimony can also be affected by different forms of ZrO. + ZrAr + Different degrees of interference from complex ions.

[0006] To combat polyatomic ion interference, conventional ICP-MS commonly uses a collision cell mode, introducing inert gases such as helium. The principle is based on the fact that the kinetic energy loss of polyatomic ions after colliding with the inert gas is greater than that of the analyte ions; by setting kinetic energy discrimination, low-kinetic-energy interfering ions are filtered out. However, the collision mode has inherent limitations. First, it is essentially ineffective against isotopic interference with mass numbers very close to those of the interfering ions. Second, for some polyatomic ions with high binding energies, the collisional dissociation efficiency is limited, resulting in incomplete interference elimination.

[0007] Besides mass spectrometry interference, matrix effects are also a key factor limiting detection accuracy and sensitivity. High concentrations of zirconium matrix alter the viscosity, surface tension, and transport efficiency of the sample solution, leading to fluctuations in injection volume and nebulization efficiency, and generating non-mass spectrometry physical effects. Simultaneously, high concentrations of zirconium ions consume a significant amount of plasma energy, potentially causing localized plasma cooling and affecting the ionization efficiency of the analyte, i.e., producing an ionization suppression effect. These matrix effects result in signal drift, decreased sensitivity, and deterioration of the detection limit, and are difficult to fully correct using conventional internal standard methods.

[0008] The reaction cell technology of inductively coupled plasma tandem mass spectrometry (ICP-MS / MS) adds a quadrupole mass analyzer to the conventional quadrupole ICP-MS. It can control the types of ions entering the reaction cell and actively eliminate interference by introducing specific reaction gases into the reaction cell and utilizing the difference in reaction kinetics between analyte ions and interfering ions and reaction gases.

[0009] However, existing research on ICP-MS / MS reaction modes for eliminating zirconium matrix interferences largely focuses on verifying solutions for specific elements or types of interference. These studies or solutions have the following limitations: First, these methods often focus on individual optimizations targeting one or two elements, lacking a systematic and holistic approach to detecting all key impurity elements in organozirconium precursors, including Li, Be, B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Co, Zn, Ga, In, Ba, and U. Different elements exhibit significant differences in mass spectrometry behavior, ionization potential, and reaction characteristics with reactant gases, necessitating personalized optimization of reaction modes and parameters for each element or element group. Current technologies lack such a systematic approach.

[0010] Secondly, existing solutions are mostly designed for geological samples, alloy samples and other matrices. The matrix concentration, acidity and coexisting ion environment after digestion of organozirconium precursors have their own characteristics. Directly applying methods to other matrices may lead to new matrix effects or signal suppression.

[0011] Furthermore, the performance of ICP-MS / MS instruments is highly dependent on the synergistic optimization of numerous operating parameters. These parameters are interrelated and jointly affect plasma stability, ion transport efficiency, collision reaction process within the reaction cell, and the final quality of the analytical signal.

[0012] In summary, current technologies lack a systematic and effective pretreatment and analytical method for detecting trace metal impurities in organozzirconium precursors. This method should systematically and effectively eliminate the comprehensive mass spectrometry interference and matrix effects caused by the zirconium matrix, and simultaneously and accurately and sensitively determine multiple key impurity elements, including light elements and easily affected elements. Therefore, developing a detection method that is highly efficient in sample pretreatment, reliable in instrumental analysis, can accurately overcome zirconium matrix interference, and enables the accurate determination of multiple trace metal impurities has become an urgent technical problem to be solved in this field. Summary of the Invention

[0013] To address the shortcomings of existing technologies for detecting trace metallic impurities in organozirconium precursors, there is a lack of a pretreatment and analytical method that can systematically and effectively eliminate the comprehensive mass spectrometry interference and matrix effects caused by the zirconium matrix, and simultaneously and accurately and sensitively determine multiple key impurity elements, including light elements and easily affected elements. Therefore, this application proposes a method for detecting the content of metallic impurities in organozirconium precursors.

[0014] The technical solution of this application is as follows: A method for detecting the content of metallic impurities in organozzirconium precursors, comprising the following steps: S1. Prepare the test solution and elemental standard solutions: Test solution: Take the zirconium precursor sample to be tested, add ultrapure hydrofluoric acid to digest it until a clear acidic solution is obtained, and then dilute the acidic solution with ultrapure water and disperse it evenly to obtain the test solution; Elemental standard solutions: Prepare standard solutions containing 20 elements: Li, Be, B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Co, Zn, Ga, In, Ba, and U. S2. Plot the standard curve to obtain the regression equation. The elemental standard solution is added to the test solution in step S1 to obtain a standard working curve solution with a concentration of 0~50 μg / L for each element. Then, the standard working curve solution is detected by an ICP-MS / MS instrument to obtain a standard curve and regression equation representing the relationship between element concentration and response signal value. S3. Calculate the content of impurity elements. Prepare a reagent blank solution using the same steps as the test solution; use ICP-MS / MS to detect the reagent blank solution and the test solution respectively, and substitute the detected response signal values ​​into the regression equation of step S2 to obtain the content of each impurity element in the organozirconium precursor to be tested.

[0015] Preferably, in step S1, the impurity content of the ultrapure hydrofluoric acid is ≤1ppt, the ratio of the mass of the zirconium precursor sample to the volume of the ultrapure hydrofluoric acid is 20mg:3mL, the resistivity of the ultrapure water is 18.2 MΩ·cm, and the ratio of the mass of the zirconium precursor sample to the volume of the solution to be tested is 1mg:1mL.

[0016] Preferably, the concentrations of Li, Be, B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Co, Zn, Ga, In, Ba, and U in the standard solution of step S1 are all 10 mg / L.

[0017] Preferably, in steps S2 and S3, when using ICP-MS / MS to test for Li, Be, B, Na, and Mg impurities in the zirconium precursor sample, the No Gas mode is used, the scan type is single-stage scan, the RF power is 1200~1600 W, the atomizing gas flow rate is 0.8~1.0 L / min, the plasma gas flow rate is 12~18 L / min, the compensation gas flow rate is 0.05~1.0 L / min, the sampling depth is 5~10 mm, the octet deflection voltage is -15~-5 V, the axial acceleration voltage is 0~2.0 V, and the energy discrimination voltage is -10~10 V.

[0018] Preferably, in steps S2 and S3, when using ICP-MS / MS to test the impurities Al, K, Ca, V, Mn, and Fe in the zirconium precursor sample, the H2 mode is used, the scanning type is tandem scanning, the RF power is 1200~1600 W, the atomizing gas flow rate is 0.5~1.0 L / min, the plasma gas flow rate is 12~18 L / min, the compensation gas flow rate is 0.1~1.0 L / min, the hydrogen flow rate is 5~10 mL / min, the sampling depth is 5~10 mm, the octet deflection voltage is -20~-5 V, the axial acceleration voltage is 0~2 V, and the energy discrimination voltage is 0~5 V.

[0019] Preferably, in steps S2 and S3, when using ICP-MS / MS to test the impurities Cr, Ni, Co, Zn, Ga, Ba, and U in the zirconium precursor sample, the He mode is used, the scan type is single-stage scan, the RF power is 1400~1600 W, the atomizing gas flow rate is 0.5~1.5 L / min, the plasma gas flow rate is 12~18 L / min, the compensation gas flow rate is 0.1~0.5 L / min, the helium flow rate is 2~10 mL / min, the sampling depth is 5~10 mm, the octet deflection voltage is -20~-15 V, the axial acceleration voltage is 0~2 V, and the energy discrimination voltage is 2~5 V.

[0020] Preferably, in steps S2 and S3, when using ICP-MS / MS to test Ti impurities in the zirconium precursor sample, the O2 mode is used, the scanning type is tandem scanning, the RF power is 1500~1600 W, the atomizing gas flow rate is 0.5~1.0 L / min, the plasma gas flow rate is 12~18 L / min, the compensation gas flow rate is 0.1~0.8 L / min, the oxygen flow rate is 10%~30%, the sampling depth is 5~10 mm, the octet deflection voltage is -5~-1 V, the axial acceleration voltage is 0.8~1.5 V, and the energy discrimination voltage is -10~-5 V.

[0021] Preferably, in steps S2 and S3, when using ICP-MS / MS to test the In impurities in the zirconium precursor sample, the NH3 / He mode is used, the scan type is tandem scan, the RF power is 1500~1600 W, the nebulizer gas flow rate is 0.5~1.0 L / min, the plasma gas flow rate is 12~18 L / min, the compensation gas flow rate is 0.1~0.8 L / min, the ammonia flow rate is 10-30%, the helium flow rate is 1-10 mL / min, the sampling depth is 5~10 mm, the octet deflection voltage is -5~-1 V, the axial acceleration voltage is 0.8~1.5 V, and the energy discrimination voltage is -20~-5 V.

[0022] Preferably, the organozirconium precursor is any one of tetraethoxyzirconium, tetrapropoxyzirconium, tetra(2,2,6,6-tetramethyl-3,5-heptadecyl)zirconium, tetra(dimethylamino)zirconium, propylcyclopentadiene tri(dimethylamino)zirconium, and tri(dimethylamino)cyclopentadienezirconium.

[0023] The beneficial effects of this application are: (1) In order to further reduce the interference of the substrate, the parameters are used in combination to make the carrier gas flow rate, auxiliary gas flow rate, RF power and other conditions all within the optimal range, thereby avoiding the generation of interference and reducing the influence of interference.

[0024] (2) This invention solves the problem by selecting different collision modes and mass number transfer through energy discrimination, charge transfer, proton transfer and other methods. For different reaction modes, the octagonal deflection voltage, appropriate reaction gas, axial acceleration and energy discrimination are controlled to selectively eliminate specific interfering ions and substrates without affecting the analyte ions, thereby improving the accuracy and sensitivity of the analysis and ensuring accurate detection of low concentration samples.

[0025] (3) The present invention uses hydrofluoric acid to pretreat the sample, so that the sample is completely digested and the metal ion impurities are released, which further improves the accuracy of detection. Detailed Implementation

[0026] To further illustrate the technical means and effects of the present invention in achieving the intended purpose, the following detailed description of the specific implementation methods, structures, features and effects of the present invention, in conjunction with preferred embodiments, is provided below. Example 1

[0027] This embodiment provides a method for detecting the content of metal impurities in organozirconium precursors. In this embodiment, high-purity electronic chemical tetra(dimethylamino)zirconium is used as the organozirconium precursor for detecting the content of metal impurities. The detection method is carried out in the following steps.

[0028] S1. Prepare the test solution 1 and the elemental standard solution. Test solution 1: Weigh 100 mg of the zirconium precursor sample to be tested into a polytetrafluoroethylene bottle in a glove box, place it on the workbench of the clean room, add 15 mL of ultrapure hydrofluoric acid to digest it into a clear acidic solution, and then dilute the acidic solution in the previous step to 100 mL with 18.2 MΩ·cm ultrapure water and disperse it evenly to obtain test solution 1; the blank solution is also diluted under the same conditions.

[0029] Elemental standard solutions: The preparation of elemental standard solutions is detailed below: Standard solutions: Prepare standard solutions containing the elements Li, Be, B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Co, Zn, Ga, In, Ba, and U, with each element having a concentration of 10 mg / L.

[0030] S2. Preparation of standard stock solution The standard solution was diluted with 18.2 MΩ·cm ultrapure water to prepare a standard stock solution with an elemental content of 100 ug / L.

[0031] S3. Plot the standard curve to obtain the regression equation. The standard stock solution was added to the test solution 1. The specific steps were as follows: First, the test solution 1 was analyzed using an ICP-MS / MS instrument, which was used as the standard operating point 1. Then, 2 mL of the standard stock solution was transferred to the test solution 1 using a pipette, and the concentration of each element was measured at 2 μg / L using an ICP-MS / MS instrument to obtain the standard operating point 2. Next, 3 mL of the standard stock solution was added to the test solution, and the concentration of each element was measured at 5 μg / L to obtain the standard operating point 3. Finally, 3 mL of the standard stock solution was added to the test solution, and the concentration of each element was measured at 8 μg / L to obtain the standard operating point 4. These four points were plotted to obtain a standard operating curve and regression equation relating the element concentration and the response signal value. The ICP-MS / MS test parameters are as follows: The ICP-MS / MS instrument used was an Agilent 8900, with a single-point peak acquisition mode, 3 repetitions, and 10 scans / repetitions. The detection parameters for each element are as follows: When testing for Li, Be, B, Na, and Mg impurities in the zirconium precursor sample, the No Gas mode was used, the scanning type was single-bar, the RF power was 1600 W, the atomizing gas flow rate was 0.9 L / min, the plasma gas flow rate was 15 L / min, the compensation gas flow rate was 0.15 L / min, the sampling depth was 7.8 mm, the octet deflection voltage was -8 V, the axial acceleration was 0 V, and the energy discrimination was 5.3 V.

[0032] When testing for Al, K, Ca, V, Mn, and Fe impurities in the zirconium precursor sample, the H2 mode was used, the scan type was cascaded, the RF power was 1600W, the atomizing gas flow rate was 0.9 L / min, the plasma gas flow rate was 15 L / min, the compensation gas flow rate was 0.15 L / min, the hydrogen flow rate was 7 mL / min, and the sampling depth was 7.8 mm; the octet deflection voltage was -18V, the axial acceleration was 0.5V, and the energy discrimination was 0V.

[0033] When testing Cr, Ni, Co, Zn, Ga, Ba, and U in the zirconium precursor sample, He mode was used, the scanning type was single-bar, the RF power was 1600W, the atomizing gas flow rate was 0.9L / min, the plasma gas flow rate was 15L / min, the compensation gas flow rate was 0.15L / min, the helium flow rate was 4.8 mL / min, the sampling depth was 7.8 mm, the octet deflection voltage was -18V, the axial acceleration was 0V, and the energy discrimination was 3V.

[0034] When testing for Ti impurities in the zirconium precursor sample, the O2 mode was used, the scanning type was serial, the RF power was 1600W, the atomizing gas flow rate was 0.9 L / min, the plasma gas flow rate was 15 L / min, the compensation gas flow rate was 0.15 L / min, the oxygen flow rate was 20%, the sampling depth was 7.8 mm, the octet deflection voltage was -3V, the axial acceleration was 1.0V, and the energy discrimination was -7V.

[0035] When testing for In impurities in the zirconium precursor sample, the NH3 / He mode was used, the scan type was cascaded, the RF power was 1600W, the atomizing gas flow rate was 0.9L / min, the plasma gas flow rate was 15 L / min, the compensation gas flow rate was 0.15 L / min, the ammonia flow rate was 25%, the helium flow rate was 1.5mL / min, the sampling depth was 7.8 mm, the octet deflection voltage was -3V, the axial acceleration was 0.5V, and the energy discrimination was -15V.

[0036] The regression equations established by the standard curves obtained from the above test results are shown in Table 1. In each regression equation, y represents the response signal value of the ICP-MS / MS test instrument, and x represents the element concentration (ppt). Table 1 Testing items Regression equation Correlation coefficient Li y = 6.218x + 3.000 0.9998 Be y=1.865x 0.9999 B y = 1.046x + 4.333 0.9998 Na y = 1.466x + 371.93 0.9998 Mg y = 11.057x + 341.27 0.9997 Al y = 0.546x + 49 0.9998 K y = 1.595x + 49 0.9993 Ca y = 3.388x + 601 0.9998 Ti y = 13.855x + 94 0.9997 V y = 1.464x + 3 0.9996 Cr y = 5.457x + 878 1.0000 Mn y = 12.962x + 127 0.9999 Fe y = 8.337x + 5666 0.9999 Ni y = 6.158x + 442 1.0000 Co y = 10.117x + 51 1.0000 Zn y = 2.4x + 296 1.0000 Ga y = 3.497x + 8 1.0000 In y = 44.246x + 13 0.9999 Ba y = 30.066x + 303 1.0000 U y = 106.085x + 0.333 1.0000 S4. Calculate the content of impurity elements. The instrument detection limits (LOD) and background equivalent concentrations (BEC) for the content of metallic impurity elements are listed in Table 2.

[0037] Table 2 Testing items Limit of detection (LOD) Background concentration (BEC) unit Li 0.02 0.48 ppt Be 0 0 ppt B 7.22 4.14 ppt Na 1.06 25.37 ppt Mg 5.29 30.86 ppt Al 8.57 90.27 ppt K 7.32 31.13 ppt Ca 5.08 177.5 ppt Ti 1.04 6.83 ppt V 2.17 2.04 ppt Cr 10.27 161.0 ppt Mn 1.05 9.87 ppt Fe 9.67 679.6 ppt Ni 6.20 71.81 ppt Co 3.46 5.10 ppt Zn 7.26 123.4 ppt Ga 3.91 2.38 ppt In 0.302 0.309 ppt Ba 1.963 10.1 ppt U 0.011 0.003 ppt Test case The impurity element content of tetra(dimethylamino)zirconium samples was tested according to the method in Example 1 to verify the repeatability, reproducibility, linearity, and recovery of the method. The standard curve reflects the linear quantitative relationship between different concentrations of the analyte and the instrument response value; the correlation coefficient R value of each analyte calibration curve should satisfy R≥0.995. Repeatability and reproducibility, measured under controlled conditions, reflect the magnitude of errors in the measurement system and are expressed as relative standard deviation (RSD). Repeatability RSD ≤ 10%, and reproducibility RSD ≤ 10%. Recovery rate is typically used to evaluate the accuracy and reliability of the method; the standard requires a recovery rate between 80% and 120%. The linear correlation coefficients, repeatability, reproducibility, and recovery rates obtained by testing tetra(dimethylamino)zirconium samples according to the method of Example 1 are listed in Table 3.

[0038] Table 3 Testing items Correlation coefficient R Repeatability RSD / 100% Reproducibility RSD / 100% Recovery rate / 100% Li 0.9998 3.2 2.1 107.3 Be 0.9999 4.8 1.3 109.6 B 0.9998 5.9 3.6 110.4 Na 0.9998 4.7 2.7 105.5 Mg 0.9997 6.3 1.9 107.6 Al 0.9998 3.8 2.8 99.3 K 0.9993 5.1 1.6 101.4 Ca 0.9998 7.2 5.3 104.5 Ti 0.9997 2.1 1.8 110.3 V 0.9996 3.0 2.4 106.7 Cr 1.0000 2.9 2.1 104.8 Mn 0.9999 2.5 1.9 98.1 Fe 0.9999 5.4 3.5 96.7 Ni 1.0000 4.2 1.4 107.2 Co 1.0000 3.6 1.6 106.4 Zn 1.0000 2.8 2.9 103.5 Ga 1.0000 2.1 3.7 107.7 In 0.9999 1.9 4.0 105.6 Ba 1.0000 3.7 3.4 99.1 U 1.0000 3.5 3.2 110.7 Analysis of the data in Table 3 shows that the detection method in Example 1 can meet the standard requirements for linear correlation coefficient, repeatability, reproducibility, and recovery rate. This indicates that the detection method in Example 1 is feasible, can reduce the detection limit of impurity elements, and achieve better detection results.

[0039] Comparative Example 1 Compared with Example 1, the difference is that the testing instrument was replaced by Thermo Fisher iCAPRQ instead of Agilent 8900. When testing for impurities of Li, Na, Mg, Al, K, Ca, Cr, Fe, and Mn in the sample, Cold-Ins mode was used, the scanning type was single rod, the RF power was 520W, the atomizing gas flow rate was 1.2L / min, the plasma gas flow rate was 14L / min, the auxiliary gas flow rate was 0.8L / min, the sampling depth was 10mm, the horizontal position of the rectangular tube was 1.24mm, the vertical position of the rectangular tube was -0.75mm, the extraction lens voltage was -200V, the focusing lens voltage was 14V, the negative electrode voltage of the extraction lens was -35V, the CCT focusing lens voltage was -20V, the CCT inlet voltage was -120V, and the CCT deflection voltage was -18V.

[0040] When testing Be, B, Ti, V, Ni, Zn, Ga, In, Ba, and U in the sample, He mode was used, the scanning type was single rod, the RF power was 1500W, the atomizing gas flow rate was 1.0L / min, the plasma gas flow rate was 14L / min, the auxiliary gas flow rate was 0.8L / min, the sampling depth was 5mm, the horizontal position of the rectangular tube was 0.44mm, the vertical position of the rectangular tube was -0.42mm, the extraction lens voltage was -188V, the focusing lens voltage was -7.5V, the negative electrode voltage of the extraction lens was 0V, the CCT focusing lens voltage was 2.5V, the CCT inlet voltage was -110V, and the CCT deflection voltage was -21V. The other steps and conditions are exactly the same. The instrument detection limits and background equivalent concentrations of the impurity elements are finally listed in Table 4.

[0041] Table 4 Testing items Limit of detection (LOD) Background concentration (BEC) unit Li 0.65 0.98 ppt Be 0 0 ppt B 14.99 45.28 ppt Na 12.82 569.77 ppt Mg 4.58 65.81 ppt Al 57.67 103.66 ppt K 15.99 27.21 ppt Ca 6.75 463.18 ppt Ti 1.73 2.34 ppt V 3.55 1.05 ppt Cr 86.02 139.4 ppt Mn 2.78 10.22 ppt Fe 16.93 1264.1 ppt Ni 10.61 63.57 ppt Co 4.34 2.97 ppt Zn 23.93 489.73 ppt Ga 4.41 1.04 ppt In 0.392 0.157 ppt Ba 2.117 23.69 ppt U 0.016 0.001 ppt Analysis of the data in Table 4 reveals that the LOD values ​​of some elements tested by the Thermo Fisher iCAPRQ instrument are higher than those tested by the Agilent 8900 instrument in Example 1. The LOD values ​​of Al and Cr are even as high as tens of ppt, while the LOD values ​​of most of these elements tested in Example 1 are below 10 ppt. This indicates that the method of using the Agilent 8900 instrument in Example 1 can significantly improve the LOD values ​​of Al and Cr elements.

[0042] Comparative Example 2 Compared to Example 1, the only difference is that when testing for Li, Be, B, Na, Mg, Al, K, Ca, V, Mn, and Fe impurities in the tetrakis(dimethylamino)zirconium sample, He mode was used, the scan type was single-bar, the RF power was 1600W, the nebulizer gas flow rate was 0.7L / min, the plasma gas flow rate was 15L / min, the auxiliary gas flow rate was 0.9L / min, the sampling depth was 9mm, the octet deflection voltage was -18V, the axial acceleration was 1V, and the energy discrimination was 3V. All other steps and conditions were exactly the same. The instrument detection limits and background equivalent concentrations (BECs, calculated by substituting the background instrument response signal value into the standard curve equation, reflecting the instrument's signal-to-background ratio and detection capability during measurement. In ICP-MS analysis, BECs can help eliminate background signal interference, thus more accurately determining the elemental concentrations in the sample) are listed in Table 5.

[0043] Table 5 Testing items Limit of detection (LOD) Background concentration (BEC) unit Li 0.76 3.66 ppt Be 0 0.29 ppt B 40.39 69.27 ppt Na 29.17 453.7 ppt Mg 89.37 231.59 ppt Al 109.55 256.31 ppt K 132.68 59.37 ppt Ca 90.27 395.43 ppt V 66.23 6.34 ppt Mn 50.37 9.37 ppt Fe 159.70 1399.7 ppt Analysis of the data in Table 5 shows that the LOD values ​​of most light elements in the He mode are above 20 ppt, and the LOD values ​​of K, Ca, and Fe are above 80 ppt. In contrast, the LOD values ​​of most light elements tested in Example 1 are almost below 10 ppt. This indicates that the No Gas mode and H2 mode method used in Example 1 can significantly improve the LOD values ​​of these hydrogen elements.

[0044] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for detecting the content of metallic impurities in organozirconium precursors, characterized in that, Includes the following steps: S1. Prepare the test solution and elemental standard solutions: Test solution: Take the zirconium precursor sample to be tested, add ultrapure hydrofluoric acid to digest it until a clear acidic solution is obtained, and then dilute the acidic solution with ultrapure water and disperse it evenly to obtain the test solution; Elemental standard solutions: Prepare standard solutions containing 20 elements: Li, Be, B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Co, Zn, Ga, In, Ba, and U. S2. Plot the standard curve to obtain the regression equation. The elemental standard solution is added to the test solution in step S1 to obtain a standard working curve solution with a concentration of 0~50 μg / L for each element. Then, the standard working curve solution is detected by an ICP-MS / MS instrument to obtain a standard curve and regression equation representing the relationship between element concentration and response signal value. S3. Calculate the content of impurity elements. Prepare a reagent blank solution using the same steps as the preparation of the test solution; The reagent blank solution and the test solution were detected by ICP-MS / MS, respectively. The detected response signal values ​​were substituted into the regression equation in step S2 to obtain the content of each impurity element in the organozirconium precursor to be tested.

2. The method for detecting the content of metal impurities in an organozirconium precursor according to claim 1, characterized in that, In step S1, the impurity content of the ultrapure hydrofluoric acid is ≤1ppt, the ratio of the mass of the zirconium precursor sample to the volume of the ultrapure hydrofluoric acid is 20mg:3mL, the resistivity of the ultrapure water is 18.2 MΩ·cm, and the ratio of the mass of the zirconium precursor sample to the volume of the test solution is 1mg:1mL.

3. The method for detecting the content of metal impurities in an organozirconium precursor according to claim 1, characterized in that, The concentrations of Li, Be, B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Co, Zn, Ga, In, Ba, and U in the standard solution of step S1 are all 10 mg / L.

4. The method for detecting the content of metal impurities in an organozirconium precursor according to claim 1, characterized in that, In steps S2 and S3, when using ICP-MS / MS to test for Li, Be, B, Na, and Mg impurities in the zirconium precursor sample, the No Gas mode was used, the scan type was single-stage scan, the RF power was 1200~1600 W, the atomizing gas flow rate was 0.8~1.0 L / min, the plasma gas flow rate was 12~18 L / min, the compensation gas flow rate was 0.05~1.0 L / min, the sampling depth was 5~10 mm, the octet deflection voltage was -15~-5 V, the axial acceleration voltage was 0~2.0 V, and the energy discrimination voltage was -10~10 V.

5. The method for detecting the content of metal impurities in an organozirconium precursor according to claim 1, characterized in that, In steps S2 and S3, when using ICP-MS / MS to test the impurities Al, K, Ca, V, Mn, and Fe in the zirconium precursor sample, the H2 mode is used, the scanning type is tandem scanning, the RF power is 1200~1600 W, the nebulizer gas flow rate is 0.5~1.0 L / min, the plasma gas flow rate is 12~18 L / min, the compensation gas flow rate is 0.1~1.0 L / min, the hydrogen flow rate is 5~10 mL / min, the sampling depth is 5~10 mm, the octet deflection voltage is -20~-5 V, the axial acceleration voltage is 0~2 V, and the energy discrimination voltage is 0~5 V.

6. The method for detecting the content of metal impurities in an organozirconium precursor according to claim 1, characterized in that, In steps S2 and S3, when using ICP-MS / MS to test the impurities Cr, Ni, Co, Zn, Ga, Ba, and U in the zirconium precursor sample, the He mode was used, the scan type was single-stage scan, the RF power was 1400~1600 W, the nebulizer gas flow rate was 0.5~1.5 L / min, the plasma gas flow rate was 12~18 L / min, the compensation gas flow rate was 0.1~0.5 L / min, the helium flow rate was 2~10 mL / min, the sampling depth was 5~10 mm, the octet deflection voltage was -20~-15 V, the axial acceleration voltage was 0~2 V, and the energy discrimination voltage was 2~5 V.

7. The method for detecting the content of metal impurities in an organozirconium precursor according to claim 1, characterized in that, In steps S2 and S3, when using ICP-MS / MS to test Ti impurities in the zirconium precursor sample, the O2 mode is used, the scanning type is tandem scanning, the RF power is 1500~1600 W, the atomizing gas flow rate is 0.5~1.0 L / min, the plasma gas flow rate is 12~18 L / min, the compensation gas flow rate is 0.1~0.8 L / min, the oxygen flow rate is 10%~30%, the sampling depth is 5~10 mm, the octet deflection voltage is -5~-1 V, the axial acceleration voltage is 0.8~1.5 V, and the energy discrimination voltage is -10~-5 V.

8. The method for detecting the content of metal impurities in an organozirconium precursor according to claim 1, characterized in that, In steps S2 and S3, when ICP-MS / MS is used to test the In impurities in the zirconium precursor sample, the NH3 / He mode is used, the scan type is tandem scan, the RF power is 1500~1600 W, the nebulizer gas flow rate is 0.5~1.0 L / min, the plasma gas flow rate is 12~18 L / min, the compensation gas flow rate is 0.1~0.8 L / min, the ammonia flow rate is 10-30%, the helium flow rate is 1-10 mL / min, the sampling depth is 5~10 mm, the octet deflection voltage is -5~-1 V, the axial acceleration voltage is 0.8~1.5 V, and the energy discrimination voltage is -20~-5 V.

9. The method for detecting the content of metal impurities in an organozirconium precursor according to claim 1, characterized in that, The organozirconium precursor is any one of tetraethoxyzirconium, tetrapropoxyzirconium, tetra(2,2,6,6-tetramethyl-3,5-heptadecyl)zirconium, tetra(dimethylamino)zirconium, propylcyclopentadiene tri(dimethylamino)zirconium, and tri(dimethylamino)cyclopentadienezirconium.