Hundred-nanometer inner surface roughness laboratory comparison sample and preparation and verification method thereof

Abstract

The invention discloses a hundred-nanometer inner surface roughness inter-laboratory comparison sample and a preparation and verification method, and belongs to the field of material surface topography analysis, and the hundred-nanometer inner surface roughness inter-laboratory comparison sample comprises the following steps: (1) preparing a titanium-containing metal film material as a comparison sample through a physical vapor deposition method; (2) roughly searching the characteristic area of the titanium metal film material sample to the position under a lens in a 1-time objective lens field of view, sequentially selecting objective lenses with 10-time, 20-time and 50-time amplification factors, continuously moving the sample, ensuring that the characteristic area of the titanium metal film material sample is kept under the lens, and marking by using a Vickers hardness tester; the preparation method has the beneficial effects that the comparison sample which is simpler and easier to obtain and has the average roughness within 100nm is prepared, and the reliability of the preparation method of the 100nm inner surface roughness inter-laboratory comparison sample is proved through verification.

Description

Technical Field

[0001] The present invention relates to the field of material surface morphology analysis, and in particular to a sample for comparing internal surface roughness between laboratories of 100 nanometers and a preparation and verification method thereof. Background Art

[0002] The surface morphology of materials is an important parameter for evaluating the surface properties of workpieces. Due to the development of chips, semiconductors, precision machining and other fields, the requirements for the roughness of material surfaces are getting higher and higher. The demand for inspection and testing of flat surfaces with a surface roughness of hundreds of nanometers is growing rapidly. Before the inspection and testing agency conducts roughness inspection and testing, it is necessary to verify the laboratory capabilities of the inspection and testing agency. In the surface roughness testing project, the way to verify the laboratory capabilities of the inspection and testing agency is to compare laboratories. Therefore, there is an urgent need for 100nm surface roughness samples that meet the needs of the industry.

[0003] At present, laboratory comparisons usually use ordered grid structures on flat surfaces published by my country's metrology institutions for instrument calibration in nanometer surface roughness analysis methods. The roughness of these ordered grid structures on flat surfaces is quite different from that of actual samples. Therefore, in the process of capability evaluation of inspection and testing laboratories, there is a lack of simpler and more accessible comparison samples with an average roughness of 100 nanometers.

[0004] Chinese invention patent authorization announcement number CN103017692B discloses a composite calibration standard and calibration method, including a substrate, the substrate having an upper end face and a lower end face, the lower end face is a mounting bottom face, the upper end face is a test end face, the test end face is provided with two or more steps, a horizontal step surface is provided on the step, and a standard grid or a standard surface roughness is provided on the step surface. The patent uses a standard grid or a standard surface roughness for calibration, but does not disclose how to make a standard grid or a standard surface roughness.

[0005] China's invention patent authorization announcement number CN109659221B discloses a method for preparing a silicon carbide single crystal film, and uses an atomic force microscope to measure the surface roughness of the silicon carbide single crystal film. The patent only discloses the preparation process of the silicon carbide single crystal film, and does not mention how to verify the laboratory capabilities of this inspection and testing agency.

[0006] Chinese invention patent publication number CN115265460A discloses a surface roughness detection method, detection device, equipment and readable storage medium, wherein the semiconductor film surface roughness detection method includes: determining the area ratio of the first area on the film surface based on the film pattern process parameters, the first area includes multiple patterns evenly distributed; positioning multiple patterns based on the overall roughness data and area ratio of the film surface; detecting at least one of the roughness of the first area and the roughness of the second area based on the positioning result, the second area includes the area outside the first area of ​​the film surface. This patent only discloses how to detect the surface roughness of semiconductor films, and does not disclose how to verify the laboratory capabilities of this inspection and testing agency. Summary of the invention

[0007] The technical problem to be solved by the present invention is that in the existing capability evaluation process of inspection and testing laboratories, there is a lack of simpler and more easily available comparison samples with an average roughness within 100 nanometers. For this purpose, a comparison sample of surface roughness within 100 nanometers between laboratories and a preparation and verification method are provided.

[0008] The technical solution of the present invention is: a method for preparing a laboratory comparison sample of a hundred-nanometer inner surface roughness, comprising the following steps: (1) preparing a titanium-containing metal thin film material as a comparison sample by a physical vapor deposition method; (2) roughly searching for a characteristic area of ​​the titanium metal thin film material sample directly below the lens under a 1x objective lens field of view, selecting objective lenses with 10x, 20x and 50x magnifications in turn and continuously moving the sample to ensure that the characteristic area of ​​the titanium metal thin film material sample remains directly below the lens, and marking it using a Vickers hardness tester.

[0009] The physical vapor deposition method of step (1) described in the above scheme comprises the following steps: (1.1) sample pretreatment, before physical vapor deposition, ultrasonically cleaning the surface of the single crystal silicon substrate with water, acetone or ethanol to remove pollutants; (1.2) before physical vapor deposition, using argon plasma to etch the single crystal silicon substrate for 10 minutes to remove the natural oxide layer on the surface of the single crystal silicon substrate; (1.3) the distance between the target and the sample is 10cm-15cm; (1.4) using argon gas with a purity of 99.99% as the working gas and high-purity titanium with a purity of 99.99% as the target, using magnetron sputtering plasma equipment to sputter titanium metal film, the argon gas flow rate is 15sccm-20sccm, the sputtering power is 100W-300W, the working gas pressure is 0.1Pa-10Pa, the deposition temperature is 100℃-300℃, and the sputtering time is 20min -150min; (1.5) The thickness of the titanium metal film is regulated by changing the deposition time, and the film thickness is 0.3μm -4μm.

[0010] In the titanium metal thin film material sample described in the above scheme, the size of the titanium metal particles on the surface is 150nm-300nm, the particle height is 5nm-100nm, and the average roughness of the sample surface is 10nm-50nm.

[0011] The Vickers hardness tester scale in the above scheme is 0.005HV-0.5HV, the interval of the marking points is 5μm-15μm, the number of marking points is 1-5 marking points, the marking range is square or rectangular, and the side length of the marking range is 1μm-20μm.

[0012] The 100-nanometer internal surface roughness inter-laboratory comparison sample is prepared by the preparation method of the 100-nanometer internal surface roughness inter-laboratory comparison sample as described above.

[0013] The verification method for inter-laboratory comparison of samples with 100-nanometer internal surface roughness is as follows: different personnel use the same atomic force microscope to scan the marked characteristic area of ​​the titanium metal thin film material sample at different times, and fix the scanning area within the marked area. The overall standard deviation of the average roughness value is recorded as 0.03 nm; atomic force microscopes of different brands and models are used to scan the marked characteristic area of ​​the titanium metal thin film material sample to ensure that the scanning area can be fixed. The overall standard deviation of the average roughness value is recorded as 1.1 nm, and the inter-laboratory comparison is completed.

[0014] The beneficial effect of the present invention is to prepare a simpler and more easily obtainable comparison sample with an average roughness within 100 nanometers, and the reliability of the preparation method of the laboratory comparison sample with an internal surface roughness of 100 nanometers has been verified. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a flow chart of the method for preparing the 100-nanometer internal surface roughness inter-laboratory comparison sample of the present invention; Figure 2 It is the atomic force microscope 2D topography and 3D stereogram of the surface roughness inter-laboratory comparison sample marked with Vickers hardness tester; Figure 3-1 , Figure 3-2 and Figure 3-3 It is a comparison chart of the test results of different personnel on the same instrument for comparing samples between laboratories; Figure 4-1 , Figure 4-2 and Figure 4-3 This is a comparison chart of the morphology and average roughness values ​​measured by three different manufacturers and different models of instruments. DETAILED DESCRIPTION

[0016] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0017] like Figure 1 As shown, the present invention includes the following steps: firstly, a titanium-containing metal thin film material is prepared as a comparison sample by a physical vapor deposition method; the surface morphology and surface roughness are analyzed according to the method of measuring the surface roughness of a sputtered thin film by an atomic force microscope in GB / T 31227-2014; then, a hardness tester is used to mark the area to be tested; finally, the comparison sample is used for comparison of atomic force microscopes of different brands and models to verify that the comparison sample can be stably and accurately positioned under atomic force microscopes of different brands (Bruker, Veeco, Shimadzu) and different models (Dimension Icon, Multimode, SPM-9700HT), thereby completing the inter-laboratory comparison.

[0018] The physical vapor deposition method comprises the following steps: (1.1) sample pretreatment, before physical vapor deposition, ultrasonically cleaning the surface of the single crystal silicon substrate with water, acetone or ethanol to remove pollutants; (1.2) before physical vapor deposition, using argon plasma to etch the single crystal silicon substrate for 10 minutes to remove the natural oxide layer on the surface of the single crystal silicon substrate; (1.3) the distance between the target and the sample is 10cm-15cm, specifically 10 cm, 12 cm, 15 cm; (1.4) using argon gas with a purity of 99.99% as the working gas and high-purity titanium with a purity of 99.99% as the target, using magnetron sputtering plasma equipment to sputter titanium metal film, the argon gas flow rate is 15sccm-20sccm, specifically 15sccm or 20sccm, the sputtering power is 100W-300W, specifically 100W, 200W or 300W, and the working gas pressure is 0.1Pa-10 Pa, specifically 0.1Pa, 5Pa or 10Pa, deposition temperature 100℃-300℃, specifically 100℃, 200℃ or 300℃, sputtering time 20min-150min, specifically 20min, 80min or 150min; (1.5), the thickness of the titanium metal film is regulated by changing the deposition time, and the film thickness is 0.3μm-4μm, specifically 0.3μm or 0.4μm. The size of the titanium metal particles on the surface of the obtained titanium metal film material sample is 150nm-300nm, specifically 150nm, 250nm or 300nm, the particle height is 5nm-100nm, specifically 5nm, 50nm or 100nm, and the average roughness of the sample surface is 10nm-50nm, specifically 10nm, 25nm or 50nm.

[0019] like Figure 2As shown, the characteristic area of ​​the titanium thin film material sample is determined and marked by using a Vickers hardness tester. The specific scheme is as follows: using a Vickers hardness tester, roughly find the characteristic area of ​​the titanium thin film material sample to the bottom of the lens under the 1x objective lens field of view, select 10x, 20x and 50x objective lenses in turn and keep moving the sample to ensure that the characteristic area of ​​the titanium thin film material sample remains directly below the lens. The Vickers hardness tester scale used is 0.005HV -0.5HV, which can be 0.005HV, 0.15HV or 0.5HV, the interval of the marking points is 5μm -15μm, which can be 5μm, 10μm or 15μm, the number of marking points is 1-5 marking points, which can be 1, 5 or 15 marking points, the marking range is square or rectangular, and the side length of the marking range is 1μm -20μm, which can be 1μm, 10μm or 20μm.

[0020] like Figure 3-1 , Figure 3-2 and Figure 3-3 As shown, using the same atomic force microscope, different personnel scanned the marked characteristic area of ​​the titanium thin film material sample at different times and were able to fix the scanning area within the marked area. As shown in Table 1, the average roughness obtained by person 1 was 21.7nm, the average roughness obtained by person 2 was 22nm, and the average roughness obtained by person 3 was 22.1nm.

[0021]

[0022] The overall standard deviation of the average roughness value obtained is 0.03 nm; Figure 4-1 , Figure 4-2 and Figure 4-3 As shown, atomic force microscopes of different brands and models were used to scan the marked characteristic areas of titanium thin film material samples. As shown in Table 2, the average roughness (nm) of model A from manufacturer 1 is 22nm, the average roughness (nm) of model B from manufacturer 2 is 24.5nm, and the average roughness (nm) of model C from manufacturer 3 is 23.77nm.

[0023]

[0024] It was determined that the scanning area could be fixed, and the overall standard deviation of the average roughness value obtained was 1.1 nm. These verifications confirmed the reliability of this preparation method for inter-laboratory comparison of samples with internal surface roughness of 100 nanometers.

Claims

1. A method for preparing samples for inter-laboratory comparison of internal surface roughness of 100 nanometers, characterized by: The following steps are involved: (1) Prepare titanium metal thin film material as a comparison sample by physical vapor deposition method; (2) Roughly search for the characteristic area of ​​the titanium metal thin film material sample under the 1x objective lens field of view to the point directly below the lens, select 10x, 20x and 50x objective lenses in turn and keep moving the titanium metal thin film material sample to ensure that the characteristic area of ​​the titanium metal thin film material sample remains directly below the lens, and mark it with a Vickers hardness tester.

2. The method for preparing the 100-nanometer internal surface roughness inter-laboratory comparison sample according to claim 1, characterized in that: The physical vapor deposition method of step (1) comprises the following steps: (1.1) sample pretreatment, before physical vapor deposition, ultrasonically cleaning the surface of the single crystal silicon substrate with water, acetone or ethanol to remove pollutants; (1.2) before physical vapor deposition, using argon plasma to etch the single crystal silicon substrate for 10 minutes to remove the natural oxide layer on the surface of the single crystal silicon substrate; (1.3) using argon gas with a purity of 99.99% as the working gas, high-purity titanium with a purity of 99.99% as the target material, the distance between the target material and the single crystal silicon substrate is 10cm-15cm, using magnetron sputtering plasma equipment to sputter the titanium metal film, the argon gas flow rate is 15sccm-20sccm, the sputtering power is 100W-300W, and the working gas pressure is 0.1Pa-10 Pa, the deposition temperature is 100℃-300℃, and the sputtering time is 20min-150min; (1.4) During physical vapor deposition, the thickness of the titanium metal film is controlled by changing the deposition time, and the film thickness is 0.3μm-4μm.

3. The method for preparing the 100-nanometer internal surface roughness inter-laboratory comparison sample according to claim 1, characterized in that: The size of the titanium metal particles on the surface of the titanium metal thin film material sample is 150nm-300nm, the particle height is 5nm-100nm, and the average roughness of the surface of the titanium metal thin film material sample is 10nm-50nm.

4. The method for preparing a 100-nanometer internal surface roughness inter-laboratory comparison sample according to claim 1, characterized in that: The Vickers hardness tester scale is 0.005HV-0.5HV, the interval of the marking points is 5μm-15μm, the number of marking points is 1-5 marking points, the marking range is a square or a rectangle, and the side length of the marking range is 1μm-20μm. 5.100-nanometer internal surface roughness inter-laboratory comparison sample, characterized by: The sample is prepared by the method for preparing a 100-nanometer internal surface roughness inter-laboratory comparison sample as described in any one of claims 1 to 4.

6. The verification method for comparing samples of 100-nanometer internal surface roughness between laboratories according to claim 5, characterized in that: The following steps are involved: The same atomic force microscope was used to scan the marked characteristic areas of titanium metal thin film material samples by different personnel at different times. The scanning area was fixed within the marked area, and the overall standard deviation of the average roughness values ​​was recorded as 0.03nm. Atomic force microscopes of different brands and models were used to scan the marked characteristic areas of titanium metal thin film material samples to ensure that the scanning area could be fixed. The overall standard deviation of the average roughness values ​​was recorded as 1.1nm, and the inter-laboratory comparison was completed.

Images