A sample preparation method for EBSD detection of Ag sputtering target

Abstract

The present invention relates to a sample preparation method for EBSD detection of Ag sputtering target, the sample preparation method comprising the following steps: (1) Ag sputtering target is cut by wire cutting to obtain a sputtering target block; (2) the sputtering target block obtained in step (1) is subjected to first mechanical polishing, second mechanical polishing and third mechanical polishing in sequence to obtain a polished target block; (3) the polished target block obtained in step (2) is subjected to chemical etching, cleaning and drying to obtain a sample to be tested; the etching liquid used for the chemical etching in step (3) comprises a mixture of methanol, ammonia water and hydrogen peroxide. The present invention uses multiple mechanical polishing to make the sputtering target block have a flat surface and can eliminate the deformation stress layer on the surface; and further polishing is performed by chemical etching to obtain a flat, smooth and scratch-free sample to be tested, and after EBSD detection, the diffraction Kikuchi band is clear and the calibration rate is high.

Description

Technical Field

[0001] The invention relates to the technical field of magnetron sputtering, and in particular to a sample preparation method for EBSD detection of an Ag sputtering target. Background Art

[0002] High-purity sputtering targets are widely used in fields such as semiconductors, displays, and solar cells that have high requirements for material purity and stability. Since the internal uniformity of the sputtering target is closely related to the performance of the sputtering coating, the semiconductor field places high demands on the purity and internal microstructure of the sputtering target.

[0003] CN 112198183A discloses a method for detecting the morphology and components of a C-SiC sputtering target, wherein the C-SiC sputtering target is polished and gold-sprayed in sequence, and then SEM and EDS detection is performed. The detection method provided by the invention can observe the microstructure of the target by pre-treating the sample before detection, but can only detect larger grains and cannot perform more complex microscopic analysis.

[0004] Electron backscatter diffraction (EBSD) is a type of diffraction that retains the conventional characteristics of a scanning electron microscope while performing submicron-level spatial resolution. It can be used to analyze microstructural features such as grain size, grain boundaries, and micro-oriented texture of sputtering targets. EBSD analysis and testing requires the removal of surface stress on the sample in order to obtain the diffraction pattern on the sample surface.

[0005] CN 108802076A discloses an electrolytic polishing method for preparing pure titanium and titanium alloy EBSD samples, wherein the pure titanium or titanium alloy slices are ground with sandpaper of different specifications, and then the pure titanium or titanium alloy samples are placed in an electrolytic polishing device for electrolytic polishing, and then the samples are taken out after cleaning and blown dry to obtain the pure titanium or titanium alloy EBSD samples. However, the electrolytic polishing process is relatively complicated, and the selection of the electrolyte has a great influence on the sample.

[0006] CN 105928767A discloses a method for preparing a nickel-containing steel sample for EBSD analysis. The nickel-containing steel sample is subjected to rough machining, polishing and erosion, and then fine polishing. The fine polishing sample is cleaned to obtain the EBSD analysis sample. The fine polishing process is: firstly polishing the polished and eroded sample with a diamond suspension, and then polishing the sample with an aluminum oxide suspension. The method is simple and convenient to operate when preparing the sample for EBSD analysis, but there is a risk of introducing impurities for high-purity sputtering target samples.

[0007] High-purity Ag sputtering targets are widely used in the preparation of high-performance thin films in the field of semiconductors and information recording media due to their excellent physical and chemical properties. Currently, there are few studies on the sample preparation methods for EBSD detection of high-purity Ag sputtering targets. In view of the shortcomings of the existing technology, it is necessary to provide a sample preparation method for EBSD detection of Ag sputtering targets with high efficiency and accurate detection. Summary of the invention

[0008] The purpose of the present invention is to provide a sample preparation method for EBSD detection of Ag sputtering target materials, which adopts multiple mechanical grinding and polishing to obtain a polished target block with a smooth surface, and uses a mixed solution of methanol, ammonia water and hydrogen peroxide as an etching solution for chemical etching. The surface of the obtained sample to be tested is flat, smooth and scratch-free, and the diffraction Kikuchi band is clear after EBSD detection, and the calibration rate is high.

[0009] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0010] The present invention provides a sample preparation method for EBSD detection of Ag sputtering target, and the sample preparation method comprises the following steps:

[0011] (1) Ag sputtering target is cut into wires to obtain sputtering target blocks;

[0012] (2) The sputtering target block obtained in step (1) is subjected to a first mechanical polishing, a second mechanical polishing, and a third mechanical polishing in sequence to obtain a polished target block;

[0013] (3) chemically corroding, cleaning and drying the polishing target block obtained in step (2) to obtain a sample to be tested;

[0014] The etching solution used in the chemical etching in step (3) includes a mixture of methanol, ammonia water and hydrogen peroxide.

[0015] The sample preparation method provided by the present invention first adopts wire cutting technology to prepare a sputtering target block of standard specifications, and through multiple mechanical grinding and polishing, the sputtering target block has a preliminary flat surface and can effectively eliminate the deformation stress layer on the surface; then it is further polished by chemical corrosion, and a mixed solution of methanol, ammonia water and hydrogen peroxide is used as the corrosion liquid. Under weak alkaline conditions, the reaction rate is mild and the corrosion effect is stable, so that a flat, smooth and scratch-free sample to be tested can be obtained. After EBSD detection, the diffraction Kikuchi band is clear and the calibration rate is high.

[0016] Preferably, the Ag content in the Ag sputtering target in step (1) is greater than 99.9%, for example, it may be 99.92%, 99.95% or 99.98%, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0017] Preferably, the sputtering target block in step (1) has a length of 8-18 mm, a width of 8-18 mm, and a height of 8-12 mm.

[0018] The length of the sputtering target block is 8-18 mm, for example, 8 mm, 11 mm, 13 mm, 15 mm or 18 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0019] The width of the sputtering target block is 8-18 mm, for example, 8 mm, 11 mm, 13 mm, 15 mm or 18 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0020] The height of the sputtering target block is 8-12 mm, for example, 8 mm, 9 mm, 10 mm, 11 mm or 12 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0021] Preferably, the first mechanical polishing in step (2) is performed using 220-280# SiO 2 Sandpaper is used for grinding and polishing, for example, it can be 220#, 240# or 280#.

[0022] Preferably, the time for the first mechanical polishing in step (2) is 3-5 min, for example, 3 min, 3.5 min, 4 min, 4.5 min or 5 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0023] If the time of the first mechanical polishing is too short, the polishing effect is poor; if the time is too long, the polishing efficiency will be reduced. Therefore, the present invention limits the polishing time to a reasonable range to achieve a good polishing effect.

[0024] Preferably, the second mechanical polishing in step (2) is performed using 800-1200# SiO 2 The sandpaper used for grinding and polishing may be, for example, 800#, 1000# or 1200#.

[0025] Preferably, the time for the second mechanical polishing in step (2) is 3-6 min, for example, 3 min, 3.5 min, 4 min, 5 min or 6 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0026] Preferably, the third mechanical polishing in step (2) is performed using 2000-2500# SiO 2 Sandpaper is used for grinding and polishing, for example, it can be 2000# or 2500#.

[0027] Preferably, the third mechanical polishing in step (2) is performed until there is no scratch on the surface of the sputtering target block.

[0028] The first mechanical polishing, the second mechanical polishing and the third mechanical polishing of the present invention are respectively SiO 2 The mesh numbers of the sandpaper are increased successively, that is, the sample is first ground and polished with coarse sandpaper and then further finely ground and polished with fine sandpaper, so that a flat sample surface without protrusions can be obtained, and the deformation stress layer on the sample surface can be effectively eliminated.

[0029] Preferably, the etching solution used for the chemical etching in step (3) comprises a mixture of methanol, ammonia water and hydrogen peroxide in a volume ratio of (3.5-4.5):1:1, for example, it can be 3.5:1:1, 3.8:1:1, 4:1:1, 4.2:1:1 or 4.5:1:1, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0030] The present invention strictly controls the volume ratio of the methanol, ammonia water and hydrogen peroxide, and can obtain a sample surface with good corrosion effect. If the volume ratio is too high or too low, the corrosion effect of the polishing target block will be reduced, resulting in unclear diffraction Kikuchi bands during EBSD detection and a reduced calibration rate.

[0031] Preferably, the time of the chemical etching in step (3) is 115-125 s, for example, it can be 115 s, 118 s, 120 s, 122 s or 125 s, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0032] The time of the chemical etching also needs to be limited within a reasonable range. If the time of the chemical etching is too short or too long, the surface of the obtained sample cannot fully meet the test requirements of EBSD, thereby affecting the calibration rate of the test.

[0033] Preferably, the cleaning in step (3) comprises cleaning with anhydrous ethanol.

[0034] As a preferred technical solution of the sample preparation method of the present invention, the sample preparation method comprises the following steps:

[0035] (1) Ag sputtering target with Ag content > 99.9% is cut into pieces with a length of 8-18 mm, a width of 8-18 mm, and a height of 8-12 mm;

[0036] (2) The sputtering target block obtained in step (1) was successively treated with 220-280# SiO 2 Sandpaper polishing 3-5min, 800-1200# SiO 2 Sandpaper polishing 3-6min, 2000-2500# SiO 2Grinding and polishing with sandpaper until there are no scratches on the surface of the sputtering target block to obtain a polished target block;

[0037] (3) The polishing target block obtained in step (2) is chemically etched for 115-125 seconds, cleaned with anhydrous ethanol, and blown dry to obtain a sample to be tested;

[0038] The etching solution used for the chemical etching includes a mixed solution of methanol, ammonia water and hydrogen peroxide in a volume ratio of (3.5-4.5):1:1.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The sample preparation method for EBSD detection of Ag sputtering target provided by the present invention makes the sputtering target block have a preliminary flat surface through multiple mechanical grinding and polishing, and can effectively eliminate the deformation stress layer on the surface; then a mixed solution of methanol, ammonia water and hydrogen peroxide is used as a corrosive solution for further polishing, so as to obtain a flat, smooth and scratch-free sample to be tested, and the diffraction Kikuchi band is clear after EBSD detection, and the calibration rate can reach 90-95%. DETAILED DESCRIPTION

[0041] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only used to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0042] Example 1

[0043] This embodiment provides a sample preparation method for EBSD detection of Ag sputtering target, and the sample preparation method comprises the following steps:

[0044] (1) Ag sputtering target with Ag content greater than 99.9% was cut into pieces to obtain sputtering target blocks with a length of 13 mm, a width of 13 mm, and a height of 10 mm;

[0045] (2) The sputtering target block obtained in step (1) was successively treated with 240# SiO 2 Sandpaper polishing for 4 minutes, 1000# SiO 2 Sandpaper polishing for 4 minutes, 2000# SiO 2 Grinding and polishing with sandpaper until there are no scratches on the surface of the sputtering target block to obtain a polished target block;

[0046] (3) The polishing target block obtained in step (2) is chemically corroded for 120 seconds, cleaned with anhydrous ethanol and blown dry to obtain a sample to be tested; the corrosive solution used for the chemical corrosion includes a mixture of methanol, ammonia water and hydrogen peroxide in a volume ratio of 4:1:1.

[0047] Example 2

[0048] This embodiment provides a sample preparation method for EBSD detection of Ag sputtering target, and the sample preparation method comprises the following steps:

[0049] (1) Ag sputtering target with Ag content greater than 99.9% was cut into pieces with a length of 11 mm, a width of 11 mm, and a height of 9 mm;

[0050] (2) The sputtering target block obtained in step (1) was successively treated with 240# SiO 2 Sandpaper polishing for 3.5min, 1000# SiO 2 Sandpaper polishing for 5 minutes, 2000# SiO 2 Grinding and polishing with sandpaper until there are no scratches on the surface of the sputtering target block to obtain a polished target block;

[0051] (3) The polishing target block obtained in step (2) is chemically etched for 118 seconds, cleaned with anhydrous ethanol and blown dry to obtain a sample to be tested; the etching solution used for the chemical etching includes a mixture of methanol, ammonia water and hydrogen peroxide in a volume ratio of 3.8:1:1.

[0052] Example 3

[0053] This embodiment provides a sample preparation method for EBSD detection of Ag sputtering target, and the sample preparation method comprises the following steps:

[0054] (1) Ag sputtering target with Ag content greater than 99.9% was cut into pieces to obtain sputtering target blocks with a length of 15 mm, a width of 15 mm, and a height of 11 mm;

[0055] (2) The sputtering target block obtained in step (1) was successively treated with 240# SiO 2 Sandpaper polishing for 4.5min, 1000# SiO 2 Sandpaper polishing for 3.5min, 2000# SiO 2 Grinding and polishing with sandpaper until there are no scratches on the surface of the sputtering target block to obtain a polished target block;

[0056] (3) The polishing target block obtained in step (2) is chemically etched for 122 seconds, cleaned with anhydrous ethanol and blown dry to obtain a sample to be tested; the etching solution used for the chemical etching includes a mixture of methanol, ammonia water and hydrogen peroxide in a volume ratio of 4.2:1:1.

[0057] Example 4

[0058] This embodiment provides a sample preparation method for EBSD detection of Ag sputtering target, and the sample preparation method comprises the following steps:

[0059] (1) Ag sputtering target with Ag content greater than 99.9% was cut into pieces to obtain sputtering target blocks with a length of 8 mm, a width of 8 mm, and a height of 8 mm;

[0060] (2) The sputtering target block obtained in step (1) was successively treated with 220# SiO 2 Sandpaper polishing for 3 minutes, 1200# SiO 2 Sandpaper polishing for 6 minutes, 2000# SiO 2 Grinding and polishing with sandpaper until there are no scratches on the surface of the sputtering target block to obtain a polished target block;

[0061] (3) The polishing target block obtained in step (2) is chemically etched for 115 seconds, cleaned with anhydrous ethanol and blown dry to obtain a sample to be tested; the etching solution used for the chemical etching includes a mixture of methanol, ammonia water and hydrogen peroxide in a volume ratio of 3.5:1:1.

[0062] Example 5

[0063] This embodiment provides a sample preparation method for EBSD detection of Ag sputtering target, and the sample preparation method comprises the following steps:

[0064] (1) Ag sputtering target with Ag content greater than 99.9% was cut into pieces to obtain sputtering target blocks with a length of 18 mm, a width of 18 mm, and a height of 12 mm;

[0065] (2) The sputtering target block obtained in step (1) was successively treated with 280# SiO 2 Sandpaper polishing for 5 minutes, 800# SiO 2 Sandpaper polishing for 3 minutes, 2500# SiO 2 Grinding and polishing with sandpaper until there are no scratches on the surface of the sputtering target block to obtain a polished target block;

[0066] (3) The polishing target block obtained in step (2) is chemically corroded for 125 seconds, cleaned with anhydrous ethanol and blown dry to obtain a sample to be tested; the corrosive solution used for the chemical corrosion includes a mixture of methanol, ammonia water and hydrogen peroxide in a volume ratio of 4.5:1:1.

[0067] Example 6

[0068] This embodiment provides a sample preparation method for EBSD detection of Ag sputtering targets, which is different from Embodiment 1 in that, except for adjusting the time of chemical etching in step (3) to 100 s, the rest is the same as Embodiment 1.

[0069] Example 7

[0070] This embodiment provides a sample preparation method for EBSD detection of Ag sputtering targets, which is different from Embodiment 1 in that, except for adjusting the time of the chemical etching in step (3) to 140 s, the rest is the same as Embodiment 1.

[0071] Example 8

[0072] This embodiment provides a sample preparation method for EBSD detection of Ag sputtering targets, which is different from Embodiment 1 in that, except for adjusting the volume ratio of methanol, ammonia water and hydrogen peroxide in step (3) to 3:1:1, the rest is the same as Embodiment 1.

[0073] Example 9

[0074] This embodiment provides a sample preparation method for EBSD detection of Ag sputtering targets, which is different from Embodiment 1 in that, except for adjusting the volume ratio of methanol, ammonia water and hydrogen peroxide in step (3) to 5:1:1, the rest is the same as Embodiment 1.

[0075] Comparative Example 1

[0076] This comparative example provides a sample preparation method for EBSD detection of Ag sputtering target materials. The difference from Example 1 is that the chemical etching in step (3) is replaced by electrolytic polishing. The electrolytic polishing step is: using a mixed polishing solution of methanol and 2-butoxyethanol, a voltage of 5-30V, room temperature, and a polishing time of 2-5min. The rest is the same as Example 1.

[0077] Comparative Example 2

[0078] This comparative example provides a sample preparation method for EBSD detection of Ag sputtering target materials. The difference from Example 1 is that the etching solution in step (3) is replaced by a mixture of hydrofluoric acid, hydrochloric acid, nitric acid and water, the volume ratio of hydrofluoric acid to water is 1:95, the volume ratio of hydrochloric acid to water is 1:63, and the volume ratio of nitric acid to water is 1:36. The rest is the same as Example 1.

[0079] The samples provided in Examples 1-9 and Comparative Examples 1 and 2 were subjected to EBSD testing. The testing conditions were as follows: 300× magnification, 2 μm scanning step, 15 mm working distance, and 30 kV working voltage. The calibration rates are shown in Table 1.

[0080] Table 1

[0081]

[0082]

[0083] As can be seen from Table 1, from Examples 1-5, the sample preparation method provided by the present invention adopts multiple mechanical grinding and polishing combined with chemical etching, and the obtained sample to be tested is tested by EBSD, and the diffraction Kikuchi band is clear and the calibration rate is high;

[0084] By comparing Example 1 with Examples 6 and 7, it can be seen that if the chemical etching time is too short or too long, the surface of the obtained sample cannot fully meet the test requirements of EBSD, thereby affecting the calibration rate of the test; by comparing Example 1 with Examples 8 and 9, it can be seen that if the volume ratio of each component in the etching solution exceeds the reasonable range, the etching effect of the polishing target block will be reduced, resulting in unclear diffraction Kikuchi bands during EBSD detection, and the calibration rate is also reduced;

[0085] By comparing Example 1 with Comparative Example 1, it can be seen that the calibration rate is reduced by the electrolytic polishing process compared with chemical corrosion, and electrolytic polishing equipment and electrolyte are required, and the operation is relatively cumbersome; by comparing Example 1 with Comparative Example 2, it can be seen that the chemical corrosion of the sample using an acidic corrosive solution causes a violent chemical reaction, which can easily cause excessive corrosion of the sample and an uneven surface, thereby significantly reducing the calibration rate.

[0086] In summary, the sample preparation method for EBSD detection of Ag sputtering target provided by the present invention, through multiple mechanical grinding and polishing, makes the sputtering target block have a preliminary flat surface, and can effectively eliminate the deformation stress layer on the surface; and then uses a mixed solution of methanol, ammonia water and hydrogen peroxide as a corrosive solution for further polishing, so as to obtain a flat, smooth and scratch-free sample to be tested. After EBSD detection, the diffraction Kikuchi band is clear, and the calibration rate can reach 90-95%.

[0087] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a sample for EBSD detection of a Ag sputtering target, characterized in that: The sample preparation method comprises the following steps: (1) Ag sputtering target is cut into wires to obtain sputtering target blocks; (2) The sputtering target block obtained in step (1) is subjected to a first mechanical polishing, a second mechanical polishing, and a third mechanical polishing in sequence to obtain a polished target block; (3) chemically corroding, cleaning and drying the polishing target block obtained in step (2) to obtain a sample to be tested; The etching solution used in the chemical etching in step (3) includes a mixture of methanol, ammonia water and hydrogen peroxide; The etching solution used in the chemical etching in step (3) includes a mixture of methanol, ammonia water and hydrogen peroxide in a volume ratio of (3.5-4.5):1:1; The time of the chemical etching in step (3) is 115-125s.

2. The sample preparation method according to claim 1, characterized in that: The Ag content in the Ag sputtering target in step (1) is greater than 99.9%.

3. The sample preparation method according to claim 1, characterized in that: The sputtering target block in step (1) has a length of 8-18 mm, a width of 8-18 mm, and a height of 8-12 mm.

4. The sample preparation method according to claim 1, characterized in that: Step (2) The first mechanical grinding and polishing is performed using 220-280# SiO2 sandpaper.

5. The sample preparation method according to claim 1, characterized in that: Step (2) The time of the first mechanical polishing is 3-5 minutes.

6. The sample preparation method according to claim 1, characterized in that: Step (2) The second mechanical grinding and polishing is performed using 800-1200# SiO2 sandpaper.

7. The sample preparation method according to claim 1, characterized in that: Step (2) The time of the second mechanical polishing is 3-6 minutes.

8. The sample preparation method according to claim 1, characterized in that: The third mechanical polishing in step (2) is performed by using 2000-2500# SiO2 sandpaper.

9. The sample preparation method according to claim 1, characterized in that: The third mechanical polishing in step (2) is performed until the surface of the sputtering target block is free of scratches.

10. The sample preparation method according to claim 1, characterized in that: The cleaning in step (3) includes cleaning with anhydrous ethanol.

11. The sample preparation method according to claim 1, characterized in that: The sample preparation method comprises the following steps: (1) Ag sputtering target with Ag content > 99.9% is cut into pieces with a length of 8-18 mm, a width of 8-18 mm, and a height of 8-12 mm; (2) The sputtering target block obtained in step (1) is polished with 220-280# SiO2 sandpaper for 3-5 min, 800-1200# SiO2 sandpaper for 3-6 min, and 2000-2500# SiO2 sandpaper in sequence until there are no scratches on the surface of the sputtering target block, thereby obtaining a polished target block; (3) The polishing target block obtained in step (2) is chemically etched for 115-125 seconds, cleaned with anhydrous ethanol, and blown dry to obtain a sample to be tested; The etching solution used for the chemical etching includes a mixed solution of methanol, ammonia water and hydrogen peroxide in a volume ratio of (3.5-4.5):1:1.

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