Method for detecting oxygen content in tungsten-silicon alloy

Abstract

The invention provides a method for detecting oxygen content in a tungsten-silicon alloy, which comprises the following steps: (1) carrying out acid pickling treatment on the tungsten-silicon alloy to obtain an acid pickling material; (2) washing the pickled material with water and an organic solvent to obtain a to-be-detected material; and (3) carrying out molten oxygen analysis treatment on the to-be-detected material to obtain the oxygen content in the tungsten-silicon alloy. According to the detection method, stable measurement of the low oxygen content in the tungsten-silicon alloy can be achieved, the oxygen content in the tungsten-silicon alloy can be accurately detected, and the precision is high.

Description

Technical Field

[0001] The invention belongs to the technical field of alloy material composition analysis and relates to a method for detecting the oxygen content in a tungsten silicon alloy. Background Art

[0002] Tungsten silicon alloy has the characteristics of high electrical conductivity, good high temperature resistance and excellent chemical corrosion resistance. It is widely used in the preparation of semiconductor integrated circuits, especially memories (such as dynamic random access memory (DRAM)), as a gate contact layer, diffusion barrier layer or adhesion layer.

[0003] The main preparation processes of tungsten silicon alloy include physical vapor deposition and chemical vapor deposition. During the preparation process, the raw materials used and the preparation process will cause a small amount of oxygen to be doped into the tungsten silicon alloy, and the oxygen content will directly affect the stability and density of the tungsten silicon alloy. In order to meet the requirements of the high-end electronics industry, the performance of the tungsten silicon alloy must meet the requirements of high purity and low oxygen, and ensure the uniformity of the target material's microstructure composition. The uniformity of the microstructure composition of the tungsten silicon target material requires that the powder particle size should be below 50μm. The smaller the particle size, the more uniform the microstructure. However, silicon is highly active, and micron-grade silicon powder is very easy to absorb oxygen in the atmospheric environment, resulting in the oxygen content of the final prepared target material as high as 1000ppm or more, causing the resistance of the tungsten silicon film to increase and reducing the stability of the tungsten silicon alloy. Therefore, the oxygen content of the tungsten silicon alloy must be controlled within a certain range in order to achieve better results during its application.

[0004] Many preparation methods of tungsten silicon alloys are disclosed in the prior art. However, after the tungsten silicon alloy is prepared, the oxygen content in the product cannot be accurately obtained, resulting in uneven effects during its application, affecting its actual use. Therefore, it is urgent to develop a method for detecting the oxygen content in tungsten silicon alloy, which can accurately analyze the oxygen content even for tungsten silicon alloys with low oxygen content. Summary of the invention

[0005] The purpose of the present invention is to provide a method for detecting the oxygen content in tungsten silicon alloy. The detection method of the present invention can realize the stable measurement of the low oxygen content in tungsten silicon alloy, accurately detect the oxygen content in tungsten silicon alloy with high precision.

[0006] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0007] The present invention provides a method for detecting the oxygen content in a tungsten silicon alloy, the detection method comprising the following steps:

[0008] (1) performing pickling treatment on the tungsten silicon alloy to obtain a pickled material;

[0009] (2) washing the pickled material with water and washing with an organic solvent to obtain a material to be tested;

[0010] (3) Performing molten oxygen analysis on the material to be tested to obtain the oxygen content in the tungsten silicon alloy.

[0011] In view of the high temperature tolerance, high strength and corrosion resistance of tungsten silicon alloy, the present invention pre-pickles the tungsten silicon alloy to remove impurities on the alloy surface, then washes with water to remove the acid on the alloy surface, washes with an organic solvent to remove excess water, and then uses molten oxygen analysis to convert the oxygen in the tungsten silicon alloy into other gases (such as carbon dioxide, carbon monoxide, nitric oxide, etc.) with higher detection accuracy for measurement, so as to accurately obtain the oxygen content in the tungsten silicon alloy.

[0012] Preferably, the pickling solution of the pickling treatment in step (1) comprises nitric acid, hydrofluoric acid and water.

[0013] Preferably, the mass concentration of the nitric acid is 40-70%, for example, 40%, 45%, 50%, 60% or 70%, etc., not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0014] Preferably, the mass concentration of the hydrofluoric acid is 30-60%, for example, 30%, 35%, 40%, 50% or 60%, etc., and is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0015] Preferably, the volume ratio of nitric acid, hydrofluoric acid and water is (8-12):1:(4-6), for example: 8:1:4, 9:1:5, 10:1:5, 11:1:4 or 12:1:6, etc., and is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0016] Preferably, the pickling treatment time in step (1) is 30 to 90 seconds, for example, 30 seconds, 40 seconds, 50 seconds, 70 seconds or 90 seconds, etc., and is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable.

[0017] Preferably, the number of times of washing with water in step (2) is 4 to 6 times.

[0018] Preferably, the detergent used in the organic solvent washing treatment in step (2) comprises acetone.

[0019] Preferably, the number of times of the organic solvent washing treatment in step (2) is 2 to 4 times.

[0020] Preferably, the organic solvent washing treatment in step (2) is followed by an inert gas drying treatment.

[0021] Preferably, the molten oxygen analysis treatment in step (2) includes melting the material to be tested, collecting the generated gas, and subjecting the collected gas to oxygen analysis through a solid oxidant to obtain the oxygen content in the tungsten silicon alloy.

[0022] Preferably, the solid oxidant comprises rare earth copper oxide.

[0023] Preferably, the power of the molten oxygen analysis treatment in step (2) is 4500-5500 W, for example: 4500 W, 4800 W, 5000 W, 5200 W or 5500 W, etc., not limited to the listed values, other values ​​not listed within the numerical range are also applicable.

[0024] Preferably, the integration time of the molten oxygen analysis treatment in step (2) is 30 to 40 seconds, for example, 30 seconds, 32 seconds, 35 seconds, 38 seconds or 40 seconds, etc., and is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) In view of the high temperature tolerance, high strength and corrosion resistance of tungsten silicon alloy, the present invention pre-pickles the tungsten silicon alloy to remove impurities on the alloy surface, then washes with water to remove the acid on the alloy surface, and washes with an organic solvent to remove excess water. Then, molten oxygen analysis is used to convert the oxygen in the tungsten silicon alloy into other gases (such as carbon dioxide, carbon monoxide, nitric oxide, etc.) with higher detection accuracy for measurement, so that the oxygen content in the tungsten silicon alloy can be accurately obtained.

[0027] (2) The relative standard deviation (RSD) of the detection method of the present invention can be controlled below 7%. DETAILED DESCRIPTION

[0028] 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 to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0029] Example 1

[0030] This embodiment provides a method for detecting oxygen content in tungsten silicon alloy, and the detection method comprises the following steps:

[0031] (1) nitric acid with a mass concentration of 60%, hydrofluoric acid with a mass concentration of 40% and water are mixed in a volume ratio of 10:1:5 to obtain a pickling solution, a block of tungsten silicon alloy is placed in a special beaker, and the pickling solution is added. The pickling solution covers the block of tungsten silicon alloy, and the pickling treatment is performed for 60 seconds to obtain a pickled material;

[0032] (2) The pickled material was washed with water for 5 times to remove the acid on the surface, and then washed with acetone for 3 times, and then dried with an argon gun to quickly remove the residual acetone to obtain the material to be tested;

[0033] (3) The material to be tested is subjected to molten oxygen analysis at a power of 5000 W, with an integration time of 35 s. The generated gas is collected and passed through rare earth copper oxide for oxidation treatment, and then oxygen analysis is performed to obtain the oxygen content in the tungsten silicon alloy.

[0034] Example 2

[0035] This embodiment provides a method for detecting oxygen content in tungsten silicon alloy, and the detection method comprises the following steps:

[0036] (1) 40% nitric acid, 30% hydrofluoric acid and water are mixed in a volume ratio of 12:1:4 to obtain a pickling solution, a block of tungsten silicon alloy is placed in a special beaker, and the pickling solution is added. The pickling solution covers the block of tungsten silicon alloy, and the pickling treatment is performed for 30 seconds to obtain a pickled material;

[0037] (2) The pickled material was washed with water 4 times to remove the acid on the surface, and then washed with acetone 2 times, and then dried with an argon gun to quickly remove the residual acetone to obtain the material to be tested;

[0038] (3) The material to be tested is subjected to molten oxygen analysis at a power of 4500 W, with an integration time of 40 s. The generated gas is collected and passed through rare earth copper oxide for oxidation treatment, and then oxygen analysis is performed to obtain the oxygen content in the tungsten silicon alloy.

[0039] Example 3

[0040] This embodiment provides a method for detecting oxygen content in tungsten silicon alloy, and the detection method comprises the following steps:

[0041] (1) 70% nitric acid, 60% hydrofluoric acid and water are mixed in a volume ratio of 8:1:6 to obtain a pickling solution, a block of tungsten silicon alloy is placed in a special beaker, and the pickling solution is added. The pickling solution covers the block of tungsten silicon alloy, and the pickling treatment is performed for 90 seconds to obtain a pickled material;

[0042] (2) The pickled material was washed with water for 6 times to remove the acid on the surface, and then washed with acetone for 4 times, and then dried with an argon gun to quickly remove the residual acetone to obtain the material to be tested;

[0043] (3) The material to be tested is subjected to molten oxygen analysis at a power of 5500 W, with an integration time of 30 s. The generated gas is collected and passed through rare earth copper oxide for oxidation treatment, and then oxygen analysis is performed to obtain the oxygen content in the tungsten silicon alloy.

[0044] Example 4

[0045] This embodiment provides a method for detecting oxygen content in tungsten silicon alloy, and the detection method comprises the following steps:

[0046] (1) 60% nitric acid, 40% hydrofluoric acid and water are mixed in a volume ratio of 5:1:5 to obtain a pickling solution, a block of tungsten silicon alloy is placed in a special beaker, and the pickling solution is added. The pickling solution covers the block of tungsten silicon alloy, and the pickling treatment is performed for 60 seconds to obtain a pickled material;

[0047] (2) The pickled material was washed with water for 5 times to remove the acid on the surface, and then washed with acetone for 3 times, and then dried with an argon gun to quickly remove the residual acetone to obtain the material to be tested;

[0048] (3) The material to be tested is subjected to molten oxygen analysis at a power of 5000 W, with an integration time of 35 s. The generated gas is collected and passed through rare earth copper oxide for oxidation treatment, and then oxygen analysis is performed to obtain the oxygen content in the tungsten silicon alloy.

[0049] Example 5

[0050] This embodiment provides a method for detecting oxygen content in tungsten silicon alloy, and the detection method comprises the following steps:

[0051] (1) nitric acid with a mass concentration of 60%, hydrofluoric acid with a mass concentration of 40% and water are mixed in a volume ratio of 15:1:5 to obtain a pickling solution, a block of tungsten silicon alloy is placed in a special beaker, and the pickling solution is added. The pickling solution covers the block of tungsten silicon alloy, and the pickling treatment is performed for 60 seconds to obtain a pickled material;

[0052] (2) The pickled material was washed with water for 5 times to remove the acid on the surface, and then washed with acetone for 3 times, and then dried with an argon gun to quickly remove the residual acetone to obtain the material to be tested;

[0053] (3) The material to be tested is subjected to molten oxygen analysis at a power of 5000 W, with an integration time of 35 s. The generated gas is collected and passed through rare earth copper oxide for oxidation treatment, and then oxygen analysis is performed to obtain the oxygen content in the tungsten silicon alloy.

[0054] Example 6

[0055] This embodiment provides a method for detecting oxygen content in tungsten silicon alloy, and the detection method comprises the following steps:

[0056] (1) nitric acid with a mass concentration of 60%, hydrofluoric acid with a mass concentration of 40% and water are mixed in a volume ratio of 10:1:5 to obtain a pickling solution, a block of tungsten silicon alloy is placed in a special beaker, and the pickling solution is added. The pickling solution covers the block of tungsten silicon alloy, and the pickling treatment is performed for 60 seconds to obtain a pickled material;

[0057] (2) The pickled material was washed with water for 5 times to remove the acid on the surface, and then washed with acetone for 3 times, and then dried with an argon gun to quickly remove the residual acetone to obtain the material to be tested;

[0058] (3) The material to be tested is subjected to molten oxygen analysis at a power of 4000 W, with an integration time of 35 s. The generated gas is collected and passed through rare earth copper oxide for oxidation treatment, and then oxygen analysis is performed to obtain the oxygen content in the tungsten silicon alloy.

[0059] Example 7

[0060] This embodiment provides a method for detecting oxygen content in tungsten silicon alloy, and the detection method comprises the following steps:

[0061] (1) nitric acid with a mass concentration of 60%, hydrofluoric acid with a mass concentration of 40% and water are mixed in a volume ratio of 10:1:5 to obtain a pickling solution, a block of tungsten silicon alloy is placed in a special beaker, and the pickling solution is added. The pickling solution covers the block of tungsten silicon alloy, and the pickling treatment is performed for 60 seconds to obtain a pickled material;

[0062] (2) The pickled material was washed with water for 5 times to remove the acid on the surface, and then washed with acetone for 3 times, and then dried with an argon gun to quickly remove the residual acetone to obtain the material to be tested;

[0063] (3) The material to be tested is subjected to molten oxygen analysis at a power of 6000 W, with an integration time of 35 s. The generated gas is collected and passed through rare earth copper oxide for oxidation treatment, and then oxygen analysis is performed to obtain the oxygen content in the tungsten silicon alloy.

[0064] Example 8

[0065] This embodiment provides a method for detecting oxygen content in tungsten silicon alloy, and the detection method comprises the following steps:

[0066] (1) nitric acid with a mass concentration of 60%, hydrofluoric acid with a mass concentration of 40% and water are mixed in a volume ratio of 10:1:5 to obtain a pickling solution, a block of tungsten silicon alloy is placed in a special beaker, and the pickling solution is added. The pickling solution covers the block of tungsten silicon alloy, and the pickling treatment is performed for 60 seconds to obtain a pickled material;

[0067] (2) The pickled material was washed with water for 5 times to remove the acid on the surface, and then washed with acetone for 3 times, and then dried with an argon gun to quickly remove the residual acetone to obtain the material to be tested;

[0068] (3) The material to be tested is subjected to molten oxygen analysis at a power of 5000 W, with an integration time of 20 s. The generated gas is collected and passed through rare earth copper oxide for oxidation treatment, and then oxygen analysis is performed to obtain the oxygen content in the tungsten silicon alloy.

[0069] Example 9

[0070] This embodiment provides a method for detecting oxygen content in tungsten silicon alloy, and the detection method comprises the following steps:

[0071] (1) nitric acid with a mass concentration of 60%, hydrofluoric acid with a mass concentration of 40% and water are mixed in a volume ratio of 10:1:5 to obtain a pickling solution, a block of tungsten silicon alloy is placed in a special beaker, and the pickling solution is added. The pickling solution covers the block of tungsten silicon alloy, and the pickling treatment is performed for 60 seconds to obtain a pickled material;

[0072] (2) The pickled material was washed with water for 5 times to remove the acid on the surface, and then washed with acetone for 3 times, and then dried with an argon gun to quickly remove the residual acetone to obtain the material to be tested;

[0073] (3) The material to be tested is subjected to molten oxygen analysis at a power of 5000 W, with an integration time of 50 s. The generated gas is collected and passed through rare earth copper oxide for oxidation treatment, and then oxygen analysis is performed to obtain the oxygen content in the tungsten silicon alloy.

[0074] Comparative Example 1

[0075] This comparative example provides a method for detecting the oxygen content in a tungsten silicon alloy, and the detection method comprises the following steps:

[0076] (1) mixing nitric acid with a mass concentration of 60% and water in a volume ratio of 10:5 to obtain a pickling solution, placing a block of tungsten silicon alloy in a special beaker, adding the pickling solution, wherein the pickling solution covers the block of tungsten silicon alloy, and performing pickling treatment for 60 seconds to obtain a pickled material;

[0077] (2) The pickled material was washed with water for 5 times to remove the acid on the surface, and then washed with acetone for 3 times, and then dried with an argon gun to quickly remove the residual acetone to obtain the material to be tested;

[0078] (3) The material to be tested is subjected to molten oxygen analysis at a power of 5000 W, with an integration time of 35 s. The generated gas is collected and passed through rare earth copper oxide for oxidation treatment, and then oxygen analysis is performed to obtain the oxygen content in the tungsten silicon alloy.

[0079] Comparative Example 2

[0080] This comparative example provides a method for detecting the oxygen content in a tungsten silicon alloy, and the detection method comprises the following steps:

[0081] (1) mixing hydrofluoric acid with a mass concentration of 40% and water in a volume ratio of 1:5 to obtain an acid wash solution, placing a block of tungsten silicon alloy in a special beaker, adding the acid wash solution, wherein the block of tungsten silicon alloy is submerged by the acid wash solution, and performing an acid wash treatment for 60 seconds to obtain an acid wash material;

[0082] (2) The pickled material was washed with water for 5 times to remove the acid on the surface, and then washed with acetone for 3 times, and then dried with an argon gun to quickly remove the residual acetone to obtain the material to be tested;

[0083] (3) The material to be tested is subjected to molten oxygen analysis at a power of 5000 W, with an integration time of 35 s. The generated gas is collected and passed through rare earth copper oxide for oxidation treatment, and then oxygen analysis is performed to obtain the oxygen content in the tungsten silicon alloy.

[0084] Comparative Example 3

[0085] This comparative example provides a method for detecting the oxygen content in a tungsten silicon alloy, and the detection method comprises the following steps:

[0086] (1) High-purity helium (4N) is introduced into the device as a carrier gas, and the sample is placed in a high-purity graphite crucible;

[0087] (2) The sample is melted at high temperature in the cavity to generate gas;

[0088] (3) The oxygen content of the gas produced after the reaction is determined by infrared method.

[0089] Performance Test:

[0090] In alloys, the relative standard deviation (RSD) of oxygen content is an important indicator for evaluating the consistency and stability of oxygen content in alloys. The relative standard deviation RSD is calculated based on the test results of the detection method described in the embodiment and the comparative example, wherein the relative standard deviation RSD is calculated as follows:

[0091] Among them, Mean is the mean value, standard deviation The results are shown in Table 1:

[0092] Table 1

[0093] Relative standard deviation RSD / % Example 1 5 Example 2 6 Example 3 7 Example 4 11 Example 5 14 Example 6 12 Example 7 13 Example 8 14 Example 9 15 Comparative Example 1 20 Comparative Example 2 21 Comparative Example 3 19

[0094] As can be seen from Table 1, from Examples 1-3, the relative standard deviation RSD of the detection method of the present invention can be controlled below 7%.

[0095] By comparing Example 1 with Examples 4-5, it can be seen that in the method for detecting the oxygen content in the tungsten silicon alloy of the present invention, the ratio of nitric acid, hydrofluoric acid and water will affect the detection effect. If the amount of nitric acid added is too low, the surface treatment is not clean. If the amount of nitric acid added is too high, the reaction speed is too fast.

[0096] By comparing Example 1 with Examples 6-7, it can be seen that in the method for detecting the oxygen content in the tungsten silicon alloy of the present invention, the power of the molten oxygen analysis treatment will affect the detection effect. If the power of the molten oxygen analysis treatment is too low, the sample will not be completely melted, resulting in a too low detection content. If the power of the molten oxygen analysis treatment is too high, W will form WO3, resulting in a low detection result.

[0097] By comparing Example 1 with Examples 8-9, it can be seen that in the method for detecting the oxygen content in the tungsten silicon alloy of the present invention, the integration time of the molten oxygen analysis treatment will affect the detection effect. If the integration time of the molten oxygen analysis treatment is too short, the detected content is low, and the oxygen released by the sample has not been completely detected. If the integration time of the molten oxygen analysis treatment is too long, it will not have a significant effect on the result, but will only waste time.

[0098] From the comparison between Example 1 and Comparative Examples 1-2, it can be seen that the present invention uses a mixed acid of hydrofluoric acid and nitric acid as a pickling solution, which can fully remove surface dirt and control the reaction speed so that the reaction speed is not too fast.

[0099] By comparing Example 1 and Comparative Example 3, it can be obtained that in view of the high temperature tolerance, high strength, corrosion resistance and other characteristics of tungsten silicon alloy, the present invention pre-pickles the tungsten silicon alloy to remove impurities on the alloy surface, then washes with water to remove the acid on the alloy surface, washes with an organic solvent to remove excess water, and then uses molten oxygen analysis to convert the oxygen in the tungsten silicon alloy into other gases (such as carbon dioxide, carbon monoxide, nitric oxide, etc.) with higher detection accuracy for measurement, so that the oxygen content in the tungsten silicon alloy can be accurately obtained.

[0100] The applicant declares that the above 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 shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for detecting oxygen content in tungsten silicon alloy, characterized in that: The detection method comprises the following steps: (1) performing pickling treatment on the tungsten silicon alloy to obtain a pickled material; (2) washing the pickled material with water and washing with an organic solvent to obtain a material to be tested; (3) Performing molten oxygen analysis on the material to be tested to obtain the oxygen content in the tungsten silicon alloy.

2. The detection method according to claim 1, characterized in that The pickling solution of the pickling treatment in step (1) comprises nitric acid, hydrofluoric acid and water; Preferably, the mass concentration of the nitric acid is 40-70%; Preferably, the mass concentration of the hydrofluoric acid is 30-60%; Preferably, the volume ratio of the nitric acid, hydrofluoric acid and water is (8-12):1:(4-6).

3. The detection method according to claim 1 or 2, characterized in that: The pickling time in step (1) is 30 to 90 seconds.

4. The detection method according to any one of claims 1 to 3, characterized in that: The number of times of water washing in step (2) is 4 to 6 times.

5. The detection method according to any one of claims 1 to 4, characterized in that: The detergent for the organic solvent washing treatment in step (2) comprises acetone; Preferably, the number of times of the organic solvent washing treatment in step (2) is 2 to 4 times.

6. The detection method according to any one of claims 1 to 5, characterized in that: The organic solvent washing treatment in step (2) is followed by an inert gas drying treatment.

7. The detection method according to any one of claims 1 to 5, characterized in that: The molten oxygen analysis treatment in step (2) includes melting the material to be tested, collecting the generated gas, and subjecting the collected gas to oxygen analysis through a solid oxidant to obtain the oxygen content in the tungsten silicon alloy.

8. The detection method according to claim 7, characterized in that The solid oxidant includes rare earth copper oxide.

9. The detection method according to any one of claims 1 to 8, characterized in that: The power of the molten oxygen analysis treatment in step (2) is 4500-5500W.

10. The detection method according to any one of claims 1 to 9, characterized in that: The integration time of the molten oxygen analysis treatment in step (2) is 30 to 40 seconds.