Testing method of fine copper wire sample for glow discharge mass spectrometer

Abstract

The invention provides a test method of a fine copper wire sample for a glow discharge mass spectrometer. The test method comprises the following steps: a sample preparation stage: preparing the fine copper wire sample through a preparation device of the fine copper wire sample for the glow discharge mass spectrometer. In the sample cleaning stage, the prepared Flat-shaped wire winding copper sample and the prepared Pin-shaped wire twisting copper sample are firstly placed in a polytetrafluoroethylene beaker of special copper, 10% dilute nitric acid is added for ultrasonic cleaning or heated to 150 DEG C for cleaning; cleaning the pickled sample with ultrapure water for 5 times, and performing ultrasonic treatment with ultrapure water for 5 minutes; and finally, carrying out ultrasonic treatment for 5 minutes by using absolute ethyl alcohol, taking out and blow-drying for later detection. A parameter optimization stage; and a sample testing stage. The method has the advantages that operation is easy, preparation efficiency is high, and contamination is not prone to occurring; the rotating speed and the up-and-down moving speed of the lifting table are adjusted, so that consistent sample gaps are ensured, stable test signals are ensured, the rolled wire samples with different diameters can be prepared according to requirements, and the practicability is high.

Description

Technical Field

[0001] The invention relates to the field of glow discharge mass spectrometry analysis in chemical component analysis, and in particular to a method for testing a micro-copper wire sample for a glow discharge mass spectrometer. Background Art

[0002] Chemical composition analysis of materials is an important test content of physical and chemical inspection. Glow discharge mass spectrometry is the most effective method for trace element detection. It has the advantages of direct solid sampling, full element analysis, fast detection speed, wide detection range, weak matrix effect, stable ion source, and excellent gas element analysis ability. It is widely used in pure metal, alloy, ceramic and coating industries, especially in the field of high-purity metals and semiconductors. It has an irreplaceable position and provides an important basis for the selection of raw materials for application products in various fields.

[0003] In actual testing, the solid samples to be tested are in various forms, including rods, blocks, powders, fine filaments, and granules. As one of the typical samples, fine filament samples are too thin to be directly placed in the fixture for clamping and testing. The fine filament samples need to be prepared into rod-shaped (pin-shaped) samples or sheet-shaped (flat-shaped) samples for testing. Manual sample preparation has the following problems:

[0004] 1. Uneven sample preparation and irregular shape and size will weaken the matrix signal and lead to unstable discharge;

[0005] 2. The sizes are not uniform, and repeated measurement is cumbersome and the accuracy is not high;

[0006] 3. Manual sample preparation can easily cause contamination and damage to the sample surface, resulting in a high level of the element to be measured;

[0007] 4. Manual sample preparation has problems such as long time, low efficiency and low safety. Summary of the invention

[0008] In view of the above technical problems, the purpose of the present invention is to provide a method for testing a micro-copper wire sample for a glow discharge mass spectrometer, which relates to a preparation device for a micro-copper wire sample for a glow discharge mass spectrometer. The present invention is a method for preparing and testing a micro-copper wire sample.

[0009] To achieve the above object, the present invention provides a method for testing a fine copper wire sample for a glow discharge mass spectrometer, comprising the following steps:

[0010] 1. Sample preparation stage:

[0011] The preparation of micro-copper wire samples is achieved by using a micro-wire sample preparation device for a glow discharge mass spectrometer.

[0012] Preparation of Flat Copper Wire Samples: For wire samples of a specific shape, pass the straight end through the wire guide through the hole of the lower clamping die of the conical wire winding on the bent side. After fixing the sample, set the rotation and lifting speed on the PLC display according to the sample diameter, and click the wire winding button. The rotating motor drives the lower clamping die of the conical wire winding to rotate together, and the lifting motor drives the lifting transmission assembly and the lifting platform to move the lower clamping die of the wire winding upward along the guide rail. After the winding sample of the lower clamping die of the conical wire winding is completed, click the wire winding button again to take out both ends of the wire winding sample and remove them all for testing.

[0013] Preparation of Pin-shaped copper wire twisting sample: bend the wire twisting sample to be tested into a shape to be determined, loosen the mold changing handle, replace the conical wire winding lower clamping mold with the wire twisting lower clamping mold, and drive the lifting transmission assembly, lifting platform and wire twisting lower clamping mold to move up and down along the lifting guide rail through the operation of the lifting motor. Adjust the position according to the sample length requirement, hang one end on the wire twisting hanging assembly, insert the other end into the wire twisting lower clamping mold, and lock the wire twisting sample through the sample clamping handle. Click the wire twisting button on the base, and the rotating motor drives the wire twisting lower clamping mold to start rotating. After the wire winding is completed, click the wire twisting button again, unscrew the sample clamping handle, and remove the sample for testing.

[0014] 2. Sample cleaning stage:

[0015] Sample cleaning: Place the prepared Flat-shaped copper coiled wire sample and Pin-shaped copper twisted wire sample in a special copper polytetrafluoroethylene beaker, add 10% dilute nitric acid for ultrasonic cleaning or heat at 150°C for cleaning, and the cleaning time is 5 minutes; wash the acid-washed sample with ultrapure water for 5 times, and then use ultrapure water for ultrasonic cleaning for 5 minutes; finally, use anhydrous ethanol for ultrasonic cleaning for 5 minutes, take out and blow dry for testing.

[0016] Preparation and cleaning of high-purity indium sheets: Put high-purity indium into 2 to 3 layers of clean sealed bags, and use a high-purity tantalum knife to cut the strip of high-purity indium into several pieces, put the cut high-purity indium into their respective sealed bags, use a sheet press to press the cut high-purity indium blocks into a thickness of about 1mm, and cut them into high-purity indium sheets with a diameter of about 15mm to 20mm. For the prepared indium sheet, put it into a special indium polytetrafluoroethylene beaker, add 10% dilute nitric acid for ultrasonic cleaning or heat it at 150℃ for cleaning, and the cleaning time is 3min; after the acid-washed indium sheet is cleaned with ultrapure water for 5 times, use ultrapure water for ultrasonic cleaning for 3min; finally, use anhydrous ethanol for ultrasonic cleaning for 3min, take it out and blow dry for testing.

[0017] 3. Parameter optimization stage:

[0018] ①Optimal selection of discharge current and discharge voltage:

[0019] a. Discharge current and discharge voltage of Pin-shaped twisted copper sample on substrate 63 Cu + Optimization of signal strength and resolution: Use pure copper standard, set the discharge voltage from 500V to 1100V, the discharge current from 1mA to 5mA, and distribute the current and voltage orthogonally. In summary, by adjusting the argon flow rate, when the discharge current is 3mA and the discharge voltage is 1100V, the signal strength is the highest, the resolution is the highest, and the stability is less than 5%.

[0020] b. The discharge current and discharge voltage of the Pin-shaped twisted copper sample have an influence on the relationship between the elements to be tested and the matrix 63 Cu + Optimization of ion beam ratio: The ratio of ion beam of each element to be measured to matrix element was studied under the conditions of current of 3mA and voltage of 500V-1100V. Except for Ni, Pb and Co, the ion beam ratio of other elements to the matrix reached the maximum value at 1100V, while the ion beam ratio of Ni, Pb and Co to the matrix was slightly lower than the maximum value at 1100V. Considering the influence of discharge current and discharge voltage on matrix signal intensity and resolution, the test conditions of current of 3mA and voltage of 1100V were selected to test Pin-shaped samples.

[0021] c. Discharge current and discharge voltage of flat copper wire sample 63 Cu + Optimization of signal strength and resolution: Use pure copper standard, set the discharge voltage from 600V to 1100V, the discharge current from 0.5mA to 3.5mA, and distribute the current and voltage orthogonally. In summary, by adjusting the argon flow rate, when the discharge current is 1.5mA and the discharge voltage is 1100V, the signal strength is the highest and the resolution is the highest; when the discharge current is 1.5mA and the discharge voltage is 1000V, the signal strength is slightly lower. In addition, under different discharge currents and discharge voltages, the substrate 63 Cu + The signal stability RSD was less than 10%.

[0022] d. Effect of discharge current and discharge voltage of flat-shaped copper wire sample on the measured elements and matrix 63 Cu +Optimization of ion beam ratio: The ratio of ion beams of each element to be tested to the matrix element was studied under the conditions of current of 1.5 mA and voltage of 600 V to 1100 V. Except for Sn, the ion beam ratios of the other elements to the matrix reached the maximum value at 1000 V. As the voltage increased to 1100 V, the ion beam ratio gradually decreased. Considering the influence of discharge current and discharge voltage on matrix signal intensity and resolution, the test conditions of current of 1.5 mA and voltage of 1000 V were selected to test the flat sample.

[0023] e. Flat-shaped copper wire sample diameter vs. substrate 63 Cu + Optimization of signal strength and resolution: Before testing the flat-shaped copper wire sample, the copper wire sample needs to be made into a circular sheet sample, and a high-purity indium sheet is used as an auxiliary cathode. Before this test, copper wire with a specification of Φ0.3mm was selected and prepared into uniformly wound circular samples with diameters of 5mm, 7mm and 9mm, and the effects of different diameters on matrix signal strength and resolution were studied. When the sample diameter is 9mm, its matrix signal strength is the largest and the resolution is the highest, so the Flat test samples are all prepared into a circle with a diameter of 9mm.

[0024] ② Optimization of pre-sputtering time:

[0025] The glow discharge process belongs to the sputtering analysis of the sample surface. The surface finish and treatment method of the sample have a great influence on the test results. In addition, during the processing and storage of the sample, it is also easy to cause the aggregation of certain elements due to contamination, which leads to a high test result.

[0026] This experiment selected pure copper standard samples and conducted a study on the pre-sputtering time for each element to be tested. The current for the Pin sample was 3mA and the voltage was 1100V; the current for the Flat sample was 1.5mA and the voltage was 1000V. Regardless of the Pin sample or the Flat sample, each element tended to be stable after sputtering for 24min to 27min. In summary, the test was started after 30min of pre-sputtering.

[0027] ③Isotope selection and mass spectrometry interference analysis:

[0028] Mass spectrometry detection is through the ionization of the substance to be measured, based on the different mass-to-charge ratios (m / z) of the ions, and then the peak spectrum intensity of each ion is measured. The interference sources of glow discharge mass spectrometry include: (1) polyatomic ion interference formed by matrix element Ni and main alloy elements and discharge gas Ar; (2) polyatomic ion interference formed by O, N and other elements in the air; (3) multi-charged ion interference of matrix elements, etc. In order to ensure the accuracy of mass spectrometry detection, the principles for selecting isotope mass numbers are: high abundance, less interference, sufficient resolution and high sensitivity.

[0029] ④Correction of relative sensitivity factor RSF:

[0030] The equipment itself has a set of standard RSF. Due to limited standard samples, this article uses pure copper standards for RSF single-point calibration, and obtains accurate test results through the calibrated RSF value.

[0031] 4. Sample testing stage:

[0032] ① High-purity tantalum calibration and testing: Both the pin-shaped twisted copper sample and the flat-shaped coiled copper sample need to use high-purity tantalum samples for quality calibration (if necessary) and IC Efficiency testing.

[0033] ② Sample parameter adjustment and pre-sputtering: After the twisted wire sample prepared in stage 1 is cleaned according to stage 2, it is placed in the reaction pool and glow discharge is started. For the coiled wire sample, the sample and the high-purity indium sheet need to be pasted together, and then placed in the equipment together, and glow discharge is started. According to the parameters optimized in stage 3, the discharge current and voltage are adjusted by adjusting the argon flow rate, and the Cu63 peak is adjusted to the maximum, and the resolution is guaranteed to reach more than 4000. The pre-sputtering time is 30 minutes to start the test.

[0034] ③Program creation and sample testing: Select each isotope to be tested and the corrected RSF according to the parameters optimized in stage 3, set Cu63 as the matrix element, save the method, and the new program is created. Add the created test program, repeat 3 times, and the average value of each element to be tested is the test result.

[0035] The test method involves a preparation device for a micro-wire sample for a glow discharge mass spectrometer, comprising: a base, a lifting motor, an emergency stop button, a wire winding button, a wire twisting button, a power switch, a PLC display screen, a rotating motor, a wire guide, a wire winding sample, a lifting platform, a lifting guide rail assembly, a mold changing base, a mold changing handle, a conical wire winding lower clamping mold, a wire twisting lower clamping mold, a sample clamping handle, a wire twisting sample, a wire twisting top plate and a wire twisting and hanging assembly. The lifting motor is placed inside the base to control the up and down movement of the lifting platform; the front of the base is equipped with a power switch, a wire twisting button, a wire winding button, an emergency stop button and a PLC display screen; the left side of the base is connected to a wire guide for precise guidance and positioning when preparing the wire winding sample, so that the wire winding sample is evenly stressed and not damaged by friction; the two sides of the base are connected to lifting guide rail assemblies, which run through the two sides of the lifting platform; the rear end of the lifting platform is connected to a lifting transmission assembly, and the lifting platform can be driven by the lifting motor to move up and down along the lifting guide rail; the front end of the lifting platform is connected to a rotating motor and a mold changing base at the bottom and top, and the rotating motor is used to wind the wire into samples and twist the wire. When the wire is sampled, the upper mold is driven to rotate. A mold changing handle is provided on the upper end of the mold changing base, which can be used to replace the conical wire winding lower locking mold or the twisting wire lower locking mold according to the sample preparation needs; the straight end of the wire winding sample of a specific shape is connected to the wire guide, and the other end is inserted into the hole of the conical wire winding lower locking mold. The rotation of the rotating motor and the up and down movement of the lifting platform can realize the preparation of the Flat-shaped wire winding copper sample; a top plate is provided on the upper end of the lifting guide rail, and a wire twisting and hanging assembly is connected to the lower end of the top plate, and the lower end of the wire twisting and hanging assembly is connected to the twisted wire sample, and the other end of the twisted wire sample is connected to the wire twisting lower locking mold and fixed with a sample pressing handle. The rotation of the rotating motor can realize the preparation of the Pin-shaped twisted wire copper sample.

[0036] This device has the following advantages:

[0037] The fine copper wire samples can be prepared into Pin-shaped twisted wire samples and Flat-shaped coiled wire samples, which are simple to operate, highly efficient to prepare, and not easy to be contaminated; the device can set the PLC program according to the diameter of the fine wire sample, adjust the rotation speed and the speed of the lifting platform moving up and down, ensure the consistency of the sample gap, and ensure the stability of the test signal; the lower clamping die of the coiling wire is provided with holes at different diameters, and Flat-shaped coiled wire samples of different diameters can be prepared according to needs, which is highly practical. The device is provided with a wire guide to ensure that the coiling process is uniformly stressed and there is no friction loss. The device is provided with an emergency stop button, which is highly safe. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A perspective view of a microfilament sample preparation device for a glow discharge mass spectrometer;

[0039] Figure 2 and Figure 3 A side view of a microfilament sample preparation device for a glow discharge mass spectrometer;

[0040] Figure 4 A front view of a microfilament sample preparation device for a glow discharge mass spectrometer;

[0041] Figure 5 A rear view of a microfilament sample preparation device for a glow discharge mass spectrometer;

[0042] Figure 6 A top view of a microfilament sample preparation device for a glow discharge mass spectrometer;

[0043] Figure 7 This is a diagram of the wire twisting structure of a micro-wire sample preparation device for a glow discharge mass spectrometer;

[0044] Figure 8 The morphological pictures of the coiled wire sample and the twisted wire sample of the micro-wire sample preparation device for glow discharge mass spectrometer are shown respectively;

[0045] Fig. 9 Pin-shaped twisted copper sample: changes in matrix 63Cu+ signal intensity and resolution at different discharge currents and discharge voltages;

[0046] Fig.10 Pin-shaped twisted copper sample: the change diagram of the ratio of each element to the matrix 63Cu+ ion beam under the discharge current of 3mA and different discharge voltages;

[0047] Fig.11 Flat-shaped copper wire sample: changes in matrix 63Cu+ signal intensity and resolution at different discharge currents and discharge voltages;

[0048] Fig.12 Flat-shaped copper wire sample: 63Cu+ ion beam ratio diagram of each element to be measured and matrix at a discharge current of 1.5mA and different discharge voltages;

[0049] Fig.13 Flat-shaped copper wire sample: the change of matrix 63Cu+ signal intensity and resolution under different sample diameters;

[0050] Fig.14 Pin-shaped twisted copper sample: Under the discharge current of 3mA and the discharge voltage of 1100V, the variation of each element to be measured with the pre-sputtering time;

[0051] Fig.15 Flat-shaped copper wire sample: the variation of each element to be measured with the pre-sputtering time at a discharge current of 1.5 mA and a discharge voltage of 1000 V;

[0052] In the figure: 1. Rotating motor, 2. Lifting transmission assembly, 3. Wire guide, 4. Wire winding sample, 5. Conical wire winding lower clamping die, 6. Wire twisting and hanging assembly, 7. Lifting guide rail, 8. Lifting platform, 9. Base, 10. Lifting motor, 11. Emergency stop button, 12. Wire winding button, 13. Wire twisting button, 14. Power switch, 15. PLC display screen, 16. Top plate, 17. Wire twisting sample, 18. Sample pressing handle, 19. Wire twisting lower clamping die, 20. Mold changing handle, 21. Mold changing base. DETAILED DESCRIPTION

[0053] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings required for use in the embodiment will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0054] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0055] like Figures 1 to 7 As shown, a micro-filament sample preparation device for a glow discharge mass spectrometer is composed of a rotation and lifting system, a switch and display combination, a wire winding system, a wire twisting system, a base 9, a top plate 16, a mold changing handle 20, and a mold changing base 21.

[0056] The rotating and lifting system is composed of a rotating motor 1, a lifting motor 10, a lifting transmission assembly 2, a lifting guide rail assembly 7 and a lifting platform 8, and is used to prepare flat-shaped wire winding samples and pin-shaped wire twisting samples.

[0057] The switch and display combination consists of an emergency stop button 11 , a wire winding button 12 , a wire twisting button 13 , a power switch 14 and a PLC display screen 15 , all of which are arranged on the base 9 .

[0058] The wire winding system is composed of a wire guide 3 arranged on the left side of a base 9, a wire winding sample 4 and a conical wire winding lower clamping mold 5 arranged on a mold changing base 21, so as to realize the preparation of a flat wire winding sample.

[0059] The wire twisting system is composed of a wire twisting and hanging assembly 6 arranged on a top plate 16, a wire twisting sample 17, a sample clamping handle 18 and a wire twisting lower clamping mold 19 arranged on a mold changing base 21, so as to realize the preparation of a Pin-shaped wire twisting sample.

[0060] Sample test method

[0061] 1. Sample preparation stage:

[0062] The above device is used to prepare flat-shaped rolled copper samples and pin-shaped twisted copper samples for glow discharge mass spectrometer micro-copper wire samples. The specific steps are as follows:

[0063] Flat copper wire sample: First press Figure 8 It is required to bend the wire winding sample 4 to be tested into a to-be-determined shape, insert the bent end into the hole of the required diameter in the lower clamping mold 5 of the conical wire winding, and pass the other straight end through the wire guide 3. After fixing the wire winding sample 4, on the PLC display screen 15, set the rising speed and rotation speed of the lower clamping mold 5 of the conical wire winding according to the diameter of the sample, click the wire winding button 12 on the base 9, and the rotating motor 1 drives the lower clamping mold 5 of the conical wire winding to start rotating. At the same time, the lifting motor 10 starts to run and drives the lifting transmission assembly 2, the lifting platform 8 and the lower clamping mold 5 of the conical wire winding to move upward along the lifting guide rail 7. After the sample preparation is completed, click the wire winding button 12 again to take out the two ends of the wire winding sample 4 and remove all of them to be tested.

[0064] Pin-shaped twisted copper sample: First press Figure 8 It is required to bend the wire twisting sample 17 to be tested into a to-be-determined shape, loosen the mold changing handle 20, replace the conical wire winding lower locking mold 5 with the wire twisting lower locking mold 19, and drive the lifting transmission assembly 2, the lifting platform 8 and the wire twisting lower locking mold 19 to move up and down along the lifting guide rail 7 through the operation of the lifting motor 10, adjust the position according to the sample length requirement, hang one end of the bending on the wire twisting hanging assembly 6, and insert the other end into the wire twisting lower locking mold 19, and lock the wire twisting sample 17 through the sample clamping handle 18, click the wire twisting button 13 on the base 9, and the rotating motor 1 drives the wire twisting lower locking mold 19 to start rotating. After the wire winding is completed, click the wire twisting button 13 again, unscrew the sample clamping handle 18, and remove the sample for testing.

[0065] 2. Sample cleaning stage:

[0066] Cleaning of the samples to be tested: Place the Flat-shaped copper coiled wire sample and Pin-shaped copper twisted wire sample prepared in the first stage into a special Cu beaker, add 10% dilute nitric acid for ultrasonic cleaning or heat at 150°C for cleaning, and the cleaning time is 5 minutes; wash the acid-washed samples with ultrapure water for 5 times, and then use ultrapure water for ultrasonic cleaning for 5 minutes; finally, use anhydrous ethanol for ultrasonic cleaning for 5 minutes, take out and blow dry for testing.

[0067] Flat coiled wire samples require the use of high-purity indium sheets as auxiliary cathodes. The preparation and cleaning of high-purity indium sheets are required.

[0068] Preparation of high-purity indium sheets: put high-purity indium into 2 to 3 layers of clean sealed bags, and use a high-purity tantalum knife to cut the strip high-purity indium into several pieces (to ensure that the high-purity indium is not contaminated, ensure that the tantalum knife is clean, and ensure that the sealed bag is not cut during the cutting process), put the cut high-purity indium into their respective sealed bags, use a sheet press to press the cut high-purity indium blocks into a thickness of about 1mm, and cut them into high-purity indium sheets with a diameter of about 15mm to 20mm. A high-purity Ta knife is also required during the cutting process, and the indium sheet is placed in a sealed bag for operation.

[0069] Cleaning of high-purity indium sheets: For the pressed high-purity indium sheets, first use 10% dilute nitric acid for ultrasonic cleaning or heat at 150°C for cleaning, and the cleaning time is 3 minutes; after the acid-washed indium sheets are cleaned with ultrapure water for 5 times, use ultrapure water for ultrasonic cleaning for 3 minutes; finally, use anhydrous ethanol for ultrasonic cleaning for 3 minutes, take out and blow dry for testing.

[0070] 3. Parameter optimization stage:

[0071] ①Optimal selection of discharge current and discharge voltage:

[0072] a. Discharge current and discharge voltage of Pin-shaped twisted copper sample on substrate 63 Cu + Optimization of signal strength and resolution: Use pure copper standard BAM-M383d, set the discharge voltage from 500V to 1100V, the discharge current from 1mA to 5mA, and distribute the current and voltage orthogonally. Fig. 9 As shown in Table 1, by adjusting the argon flow rate, when the discharge current is 3 mA and the discharge voltage is 1100 V, the signal intensity is the highest, the resolution is the highest, and the stability is less than 5%.

[0073] Table 1 Pin-shaped twisted copper sample: matrix under different discharge current and discharge voltage 63 Cu + Changes in signal strength and resolution

[0074]

[0075] b. The discharge current and discharge voltage of the Pin-shaped twisted copper sample have an influence on the relationship between the elements to be tested and the matrix 63 Cu +Optimization of ion beam ratio: The ratio of ion beam of each element to be tested to the matrix element was studied under the conditions of current of 3mA and voltage of 500V to 1100V. Except for Ni, Pb and Co, the ion beam ratio of other elements to the matrix reached the maximum value at 1100V, while the ion beam ratio of Ni, Pb and Co to the matrix was slightly lower than the maximum value at 1100V. Considering the influence of discharge current and discharge voltage on matrix signal intensity and resolution, the test conditions of current of 3mA and voltage of 1100V were selected to carry out Pin sample testing. Fig.10 As shown:

[0076] Table 2 Pin-shaped twisted copper sample: the measured elements and the matrix at the discharge current of 3mA and different discharge voltages 63 Cu + Ion beam ratio

[0077]

[0078] c. Discharge current and discharge voltage of flat copper wire sample 63 Cu + Optimization of signal strength: Use pure copper standard BAM-M383d, set the discharge voltage from 600V to 1100V, the discharge current from 0.5mA to 3.5mA, and distribute the current and voltage orthogonally. In summary, by adjusting the argon flow rate, when the discharge current is 1.5mA and the discharge voltage is 1100V, the signal strength is the highest and the resolution is the highest; when the discharge current is 1.5mA and the discharge voltage is 1000V, the signal strength is slightly lower. In addition, under different discharge currents and discharge voltages, the substrate 63 Cu + The signal stability RSD is less than 10%. Fig.11 As shown:

[0079] Table 3 Flat-shaped copper wire sample: matrix under different discharge current and discharge voltage 63 Cu + Changes in signal strength and resolution

[0080]

[0081] d. Effect of discharge current and discharge voltage of flat-shaped copper wire sample on the measured elements and matrix 63 Cu +Optimization of ion beam ratio: The ratio of ion beam of each element to be tested to the matrix element was studied under the conditions of current of 1.5mA and voltage of 600V to 1100V. Except for Sn, the ion beam ratio of other elements to the matrix reached the maximum value at 1000V. As the voltage increased to 1100V, the ion beam ratio gradually decreased. Considering the influence of discharge current and discharge voltage on matrix signal intensity and resolution, the test conditions of current of 1.5mA and voltage of 1000V were selected to test the flat sample. Fig.12 As shown:

[0082] Table 4 Flat-shaped copper wire sample: The measured elements and the matrix at the discharge current of 1.5 mA and different discharge voltages 63 Cu + Ion beam ratio

[0083]

[0084] e. Flat-shaped copper wire sample diameter vs. substrate 63 Cu + Optimization of signal strength and resolution: Before testing the flat copper wire sample, the copper wire sample needs to be made into a circular sheet sample and a high-purity indium sheet is used as an auxiliary cathode. Figure 5 As shown in the figure, before this test, copper wire with a specification of Φ0.3mm was selected and prepared into uniformly wound circular samples with diameters of 5mm, 7mm and 9mm, respectively. The signal intensity and resolution of the matrix with different diameters were studied at a current of 1.5mA and a voltage of 1000V. When the sample diameter is 9mm, its matrix signal intensity is the largest and the resolution is the highest. Therefore, the Flat test samples are all prepared into circles with a diameter of 9mm. Fig.13 As shown:

[0085] Table 5 Flat-shaped copper wire samples: matrix under different sample diameters 63 Cu + Changes in signal strength and resolution

[0086] diameter Signal Strength Resolution 5mm <![CDATA[5.0E -10 ]]> 4200 7mm <![CDATA[7.8E -10 ]]> 4400 9mm <![CDATA[9.5E -10 ]]> 4400

[0087] ② Optimization of pre-sputtering time:

[0088] The glow discharge process belongs to the sputtering analysis of the sample surface. The surface finish and treatment method of the sample have a great influence on the test results. In addition, during the processing and storage of the sample, it is also easy to cause the aggregation of certain elements due to contamination, which leads to a high test result.

[0089] In this experiment, pure copper standard samples were selected to study the pre-sputtering time of each element to be tested.

[0090] For the pin-shaped sample, the current is 3mA and the voltage is 1100V. Fig.14 shown.

[0091] Flat samples are tested at a current of 1.5 mA and a voltage of 1000 V. Fig.15 shown.

[0092] From the change of each element test result with the sputtering time, it can be seen that, no matter Pin or Flat sample, each element tends to be stable after sputtering for 24min to 27min. In summary, it is selected to start the test after pre-sputtering for 30min.

[0093] ③Isotope selection and mass spectrometry interference analysis:

[0094] Mass spectrometry detection is through the ionization of the substance to be measured, based on the different mass-to-charge ratios (m / z) of the ions, and then the peak spectrum intensity of each ion is measured. The interference sources of glow discharge mass spectrometry include: (1) polyatomic ion interference formed by matrix element Ni and main alloy elements and discharge gas Ar; (2) polyatomic ion interference formed by O, N and other elements in the air; (3) multi-charged ion interference of matrix elements, etc. In order to ensure the accuracy of mass spectrometry detection, the principles for selecting isotope mass numbers are: high abundance, less interference, sufficient resolution and high sensitivity.

[0095] Table 6 Main mass spectrometry interferences and test resolution of each element to be tested

[0096]

[0097]

[0098]

[0099] ④Correction of relative sensitivity factor RSF:

[0100] The equipment itself has a set of standard RSF. Due to limited standard samples, this paper uses pure copper standard BAM-M383d for RSF single-point calibration to obtain accurate results.

[0101] Table 7 Corrected RSF values ​​of each element to be measured

[0102] element Corrected RSF value P 3.51 Fe 1.00 Ni 1.54 Co 1.14 Zn 5.46 As 4.34 Se 3.10 Zr 0.64 Ag 4.90 Cd 4.65 Sn 2.38 Sb 3.90 Te 3.42 Pb 2.84 Bi 6.00

[0103] 4. Sample testing stage:

[0104] ①Pin-shaped twisted wire copper sample:

[0105] Calibration and testing of high-purity tantalum: After cooling the glow discharge mass spectrometer to liquid nitrogen temperature, click Load Sample, put in a high-purity tantalum pin sample, set the argon flow rate to 500 SCCM, the discharge current to 3 mA, and the voltage to 1200 V, and click Start to turn on the glow. Open Magnet in Scans, find the peak of Ta181, and ensure that the peak position is in the center of the window (if it is too offset, mass calibration is required), adjust the argon flow rate to make the voltage value around 1100 V; adjust the various parameters in Source and Analyser to maximize the signal intensity of the Ta181 peak (greater than 1.0E -09 A), and the resolution reaches 4000 or above. Set ICEfficiency in Setup to 1 and click Save. Open EscanAnalysis in Data Acquisition, add a test program, repeat 3 times, calculate the Ta180 / Ta181 ratio, fill the average of the 3 test results into the IC Efficiency box, and click Save. After the test is completed, click the Stop button to remove the high-purity tantalum.

[0106] Sample parameter adjustment and pre-sputtering: After the wire sample prepared in stage 1 is cleaned according to stage 2, it is placed in the reaction cell and glow discharge is started. According to the parameters optimized in stage 3, the discharge current is adjusted to 3mA and the voltage is about 1100V by adjusting the argon flow rate. Turn on Magnet in Scans, adjust the Cu63 peak to the maximum, and ensure that the resolution reaches more than 4000. Start the test after 30 minutes of pre-sputtering.

[0107] Program creation and sample testing: Click Set Up Analysis in Data Acquisition to create a program, select each isotope to be tested and the corrected RSF value according to the parameters optimized in stage 3, set Cu63 as the matrix element, and name and save the method. Open Escan Analysis in Data Acquisition, add the test program just created, repeat 3 times, and the average value of each element to be tested is the test result.

[0108] ②Flat-shaped copper wire sample:

[0109] High purity tantalum calibration and testing: The operation process is the same as that of ① Pin-shaped twisted copper sample, except that high purity tantalum sheets are used; settings: argon flow rate 500SCCM, discharge current 1.5mA, voltage 1200V, turn on the glow. After finding the peak of Ta181, adjust the argon flow rate so that the discharge current is 1.5mA and the voltage value is around 1000V.

[0110] Sample parameter adjustment and pre-sputtering: After the prepared coiled wire sample and the prepared high-purity indium sheet in stage 1 are cleaned according to stage 2, the high-purity indium sheet and the coiled wire sample are placed on weighing paper respectively, and the coiled wire copper sample is placed in the middle of the high-purity indium. After placing another layer of weighing paper, use a cylinder with a flat surface to press hard to ensure that the coiled wire copper sample sticks to the high-purity indium sheet and has a certain adhesion, so that the sample does not fall off during the glow sputtering process and the discharge is stable. Put the high-purity indium with the coiled wire sample into the equipment together and start the glow discharge. According to the parameters optimized in stage 3, adjust the discharge current to 1.5mA and the voltage to about 1000V by adjusting the argon flow rate, turn on the Magnet in Scans, adjust the Cu63 peak to the maximum, and ensure that the resolution reaches more than 4000. The pre-sputtering time is 30min to start the test.

[0111] Program creation and sample testing: The operation process is the same as ① Pin-shaped twisted wire copper sample.

Claims

1. A method for testing a fine copper wire sample for a glow discharge mass spectrometer, characterized in that: The steps include:

1. Sample preparation stage: The preparation of the micro-copper wire sample is realized by a micro-wire sample preparation device for a glow discharge mass spectrometer; Preparation of Flat Copper Wire Samples: For wire samples of a specific shape, pass the straight end through the hole of the lower clamping die of the conical wire winding on the bent side through the wire guide. After fixing the sample, set the rotation and lifting speeds on the PLC display screen according to the sample diameter, and click the wire winding button; the rotating motor drives the lower clamping die of the conical wire winding to rotate together, and the lifting motor drives the lifting transmission assembly and the lifting platform to move up and down, so that the lower clamping die of the wire winding moves upward along the guide rail, so that the wire winding sample is completed after the winding sample preparation of the lower clamping die of the conical wire winding is completed. Click the wire winding button again to take out both ends of the wire winding sample and remove them all for testing; Preparation of Pin-shaped copper wire twisting sample: bend the wire twisting sample to be tested into a shape to be determined, loosen the mold changing handle, replace the conical wire winding lower clamping mold with the wire twisting lower clamping mold, and drive the lifting transmission assembly, lifting platform and wire twisting lower clamping mold to move up and down along the lifting guide rail through the operation of the lifting motor. Adjust the position according to the sample length requirement, hang one end of the bending on the wire twisting hanging assembly, insert the other end into the wire twisting lower clamping mold, and lock the wire twisting sample through the sample clamping handle, click the wire twisting button on the base, and the rotating motor drives the wire twisting lower clamping mold to start rotating. After the wire winding is completed, click the wire twisting button again, unscrew the sample clamping handle, and remove the sample for testing; 2. Sample cleaning stage: Sample cleaning: Place the prepared flat-shaped copper coiled wire sample and pin-shaped copper twisted wire sample in a special copper polytetrafluoroethylene beaker, add 10% dilute nitric acid for ultrasonic cleaning or heat at 150°C for cleaning, and the cleaning time is 5 minutes; wash the acid-washed sample with ultrapure water for 5 times, and then use ultrapure water for ultrasonic cleaning for 5 minutes; finally, use anhydrous ethanol for ultrasonic cleaning for 5 minutes, take out and blow dry for testing; Preparation and cleaning of high-purity indium sheets: put high-purity indium into 2 to 3 layers of clean sealed bags, and use a high-purity tantalum knife to cut the strip high-purity indium into several pieces, put the cut high-purity indium into their respective sealed bags, use a sheet press to press the cut high-purity indium blocks into a thickness of about 1 mm, and cut them into high-purity indium sheets with a diameter of about 15 mm to 20 mm; put the prepared indium sheets into a special indium polytetrafluoroethylene beaker, add 10% dilute nitric acid for ultrasonic cleaning or heat at 150°C for cleaning, and the cleaning time is 3 minutes; wash the acid-washed indium sheets with ultrapure water for 5 times, and then use ultrapure water for ultrasonic cleaning for 3 minutes; finally, use anhydrous ethanol for ultrasonic cleaning for 3 minutes, take out and blow dry for testing; 3. Parameter optimization stage: ①Optimal selection of discharge current and discharge voltage: a. Discharge current and discharge voltage of Pin-shaped twisted copper sample on substrate 63 Cu + Optimization of signal strength and resolution: Using pure copper standard, set the discharge voltage from 500V to 1100V, the discharge current from 1mA to 5mA, and distribute the current and voltage orthogonally; In summary, by adjusting the argon flow rate, when the discharge current is 3mA and the discharge voltage is 1100V, the signal strength is the highest, the resolution is the highest, and the stability is less than 5%; b. The discharge current and discharge voltage of the Pin-shaped twisted copper sample have an influence on the relationship between the elements to be tested and the matrix 63 Cu + Optimization of ion beam ratio: The ratio of ion beam of each element to be measured to the matrix element was studied under the conditions of current of 3mA and voltage of 500V to 1100V. Except for Ni, Pb and Co, the ion beam ratio of other elements to the matrix reached the maximum value at 1100V, while the ion beam ratio of Ni, Pb and Co to the matrix was slightly lower than the maximum value at 1100V. Considering the influence of discharge current and discharge voltage on matrix signal intensity and resolution, the test conditions of current of 3mA and voltage of 1100V were selected to test the pin-shaped sample. c. Discharge current and discharge voltage of flat copper wire sample 63 Cu + Optimization of signal strength and resolution: Using pure copper standard, set the discharge voltage from 600V to 1100V, the discharge current from 0.5mA to 3.5mA, and distribute the current and voltage orthogonally; In summary, by adjusting the argon flow rate, when the discharge current is 1.5mA and the discharge voltage is 1100V, the signal strength and resolution are the highest; The signal intensity is slightly lower when the discharge current is 1.5mA and the discharge voltage is 1000V. 63 Cu + The signal stability RSDs were all less than 10%; d. Effect of discharge current and discharge voltage of flat-shaped copper wire sample on the measured elements and matrix 63 Cu + Optimization of ion beam ratio: The ratio of ion beam of each element to be measured to the matrix element was studied under the conditions of current of 1.5mA and voltage of 600V to 1100V. Except for Sn, the ion beam ratio of other elements to the matrix reached the maximum value at 1000V. As the voltage increased to 1100V, the ion beam ratio gradually decreased. Considering the influence of discharge current and discharge voltage on matrix signal intensity and resolution, the test conditions of current of 1.5mA and voltage of 1000V were selected to test the flat sample. e. Flat-shaped copper wire sample diameter vs. substrate 63 Cu + Optimization of signal intensity and resolution: Before testing the flat-shaped coiled copper sample, the copper wire sample needs to be made into a circular sheet sample, and a high-purity indium sheet is used as an auxiliary cathode; before this test, a copper wire with a specification of Φ0.3mm was selected, and uniformly wound circular samples with diameters of 5mm, 7mm and 9mm were prepared respectively, and the effects of different diameters on matrix signal intensity and resolution were studied; when the sample diameter is 9mm, its matrix signal intensity is the largest and the resolution is the highest, so the Flat test samples are all prepared into a circle with a diameter of 9mm; ② Optimization of pre-sputtering time: The glow discharge process belongs to the sputtering analysis of the sample surface. The surface finish and treatment method of the sample have a great influence on the test results. In addition, during the processing and storage of the sample, it is also easy for certain elements to gather due to contamination, which leads to high test results. This experiment selected pure copper standard samples and carried out a study on the pre-sputtering time for each element to be tested; the current of the Pin sample was 3mA and the voltage was 1100V; the current of the Flat sample was 1.5mA and the voltage was 1000V; regardless of the Pin sample or the Flat sample, each element tended to be stable after sputtering for 24min to 27min; in summary, the test was started after pre-sputtering for 30min; ③Isotope selection and mass spectrometry interference analysis: Mass spectrometry detection is through the ionization of the substance to be measured, based on the different mass-to-charge ratios (m / z) of the ions, separation, and then measurement of the peak spectrum intensity of each ion; the interference sources of glow discharge mass spectrometry include: (1) polyatomic ion interference formed by matrix element Ni and major alloying elements and discharge gas Ar; (2) polyatomic ion interference formed by O, N, etc. in the air; (3) multi-charged ion interference of matrix elements, etc.; in order to ensure the accuracy of mass spectrometry detection, the principles for selecting isotope mass numbers are: high abundance, less interference, sufficient resolution and high sensitivity; ④Correction of relative sensitivity factor RSF: The equipment itself has a set of standard RSF. Due to the limited standard samples, this paper uses pure copper standard samples for RSF single-point calibration, and obtains accurate test results through the corrected RSF value; 4. Sample testing stage: ① High-purity tantalum calibration and testing: Both the pin-shaped twisted copper sample and the flat-shaped coiled copper sample need to use high-purity tantalum samples for quality calibration (if necessary) and IC Efficiency testing; ② Sample parameter adjustment and pre-sputtering: After the wire sample prepared in the first stage is cleaned according to the second stage, it is placed in the reaction pool and the glow discharge is turned on; For the wire sample, the sample and the high-purity indium sheet need to be pasted together, and then placed in the equipment together, and glow discharge is turned on. According to the parameters optimized in stage 3, the discharge current and voltage are adjusted by adjusting the argon flow rate, and the Cu63 peak is adjusted to the maximum, and the resolution is guaranteed to reach more than 4000. The pre-sputtering time is 30 minutes before the test is started. ③Program creation and sample testing: Select each isotope to be measured and the corrected RSF according to the parameters optimized in stage 3, set Cu63 as the matrix element, save the method, and the new program is created; add the created test program, repeat 3 times, and the average value of each element to be measured is the test result.

2. The method for testing a fine copper wire sample for a glow discharge mass spectrometer according to claim 1, characterized in that: The micro-filament sample preparation device for a glow discharge mass spectrometer comprises a rotating and lifting system, a switch and display combination, a wire winding system, a wire twisting system, a base (9), a top plate (16), a mold changing handle (20), and a mold changing base (21); The rotating and lifting system is composed of a rotating motor (1), a lifting motor (10), a lifting transmission assembly (2), a lifting guide rail assembly (7) and a lifting platform (8), and is used to prepare flat-shaped wire winding samples and pin-shaped wire twisting samples; The switch and display assembly consists of an emergency stop button (11), a wire winding button (12), a wire twisting button (13), a power switch (14) and a PLC display screen (15), all of which are arranged on the base (9); The wire winding system is composed of a wire guide (3) arranged on the left side of the base (9), a wire winding sample (4) and a conical wire winding lower clamping mold (5) arranged on the mold changing base (21), so as to realize the preparation of a flat wire winding sample; The wire twisting system is composed of a wire twisting and hanging assembly (6) arranged on a top plate (16), a wire twisting sample (17), a sample clamping handle (18), and a wire twisting lower clamping mold (19) arranged on a mold changing base (21), so as to realize the preparation of a pin-shaped wire twisting sample.

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