TWI582429B - Scanning method for an atomic force microscopy - Google Patents

Description

Atomic force microscope scanning method

The present invention relates to an atomic force microscope scanning method, and more particularly to an atomic force microscope scanning method using a dual probe for scanning.

In recent years, Nanotechnology has become one of the focuses of the development of science and technology, mainly because the physical properties of substances after the scale reduction are often changed, after understanding the quantum and surface phenomena possessed by these substances at the nanometer scale. It can be used to find new ways to apply new materials or new equipment. Therefore, what is indispensable is the observation tool that can reach the atomic scale resolution. Atomic force microscopy is one of the choices.

The principle of atomic force microscopy is to make the cantilever beam slightly displaced in the scanning test piece by the atomic force between the tip and the test piece by the special micro-probe inside it, to measure the microstructure shape of the test piece surface, and the conductor And the insulator has a three-dimensional development capability. Moreover, the atomic force microscope can detect some interaction between the probe and the surface of the test piece, such as tunneling current, atomic force, magnetic force, near-field electromagnetic wave, etc., and can be applied to explore the nanometer scale. Microscopic physical properties (light, force, electricity, magnetism) measurements.

However, the conventional atomic force microscope is not suitable for different thickness and contour test pieces because the tilt angle of the probe is a fixed angle, and often the accuracy of the output data is affected by the characteristics of the test piece itself. Add another variable.

An object of the present invention is to provide an atomic force microscope scanning method for scanning a test piece by controlling a double probe on a tilt angle suitable for a specific test piece, and combining the scan data of the two probes according to the configuration at the time of scanning, which can be accurately The surface microstructure shape or microfeatures on the test piece were obtained.

According to the present invention, there is provided an atomic force microscope scanning method, which is suitable for an atomic force microscope with dual probes, comprising: aligning the probes; respectively adjusting an inclination angle of the probes to scan a test piece; The test piece is scanned with a probe to obtain a scan data; and the two scan data are combined to obtain a surface microstructure shape or micro-characteristic on the test piece.

It can be known from the above that the atomic force microscope scanning method of the present invention is designed to obtain the surface microstructure or micro-characteristics on the test piece by controlling the inclination angle of the double probe and combining scanning data, and effectively improving the accuracy of the atomic force microscope. Sex.

1‧‧‧Atomic Force Microscope

2‧‧‧ test strips

10‧‧‧Measurement unit

11, 12 ‧ ‧ probe

13‧‧‧Mirror

20‧‧‧First scanning unit

30‧‧‧Second scanning unit

40‧‧‧Data Processing Unit

50‧‧‧Track generation unit

60‧‧‧Light microscope

Figure 1 is a schematic view showing the structure of a system of an atomic force microscope to which the present invention is applied.

Figure 2 shows a schematic diagram of the positional relationship between a probe and a test piece.

To further illustrate the various embodiments, the invention is provided with the drawings. The drawings are a part of the disclosure of the present invention, and are mainly used to explain the embodiments, and the operation of the embodiments may be explained in conjunction with the related description of the specification. With reference to such content, those of ordinary skill in the art should be able to understand other possible embodiments and advantages of the present invention. Elements in the figures are not drawn to scale, and similar elements are generally used to represent similar elements.

First, please refer to Figure 1 first, which shows the atomic force applied in accordance with the present invention. A schematic diagram of one of the microscope systems. Please note that the atomic force microscope described herein is one of the embodiments to which the present invention is applicable, and the present invention is not limited thereto. As shown in FIG. 1, the atomic force microscope 1 mainly includes a measuring unit 10, a first scanning unit 20, a second scanning unit 30, and a data processing unit 40. The measuring unit 10 comprises two probes 11, 12 which are respectively directed to the test strip 2 on the stage 13.

The first scanning unit 20 and the second scanning unit 30 are respectively connected to the probes 11, 12, and the positions of the probes 11, 12 can be adjusted, for example, within either the first scanning unit 20 or the second scanning unit 30. An XY-piezoelectric displacement element can be provided to control the movement of the probe 11/12 in the XY plane and to set a Z-piezoelectric displacement element to control the height of the probe 11/12 on the Z axis, and another example is the first scanning unit. The position of the XYZ-piezoelectric displacement element control probe 11/12 on the XYZ triaxial axis may be set in either of the 20 or the second scanning unit 30, or the position of the probe 11/12 may be adjusted by other forms of driving. The components and other setting structures are not limited thereto. In this embodiment, the architecture of the embodiment is that the same trajectory generating unit 50 sends out positive and negative source output signals, and controls the first scanning unit 20 and the second scanning unit 30 respectively, and the first scanning unit 20 is provided with a The XY-piezoelectric displacement element controls the movement of the probe 11 in the XY plane and sets a Z-piezoelectric displacement element to control the height of the probe 11 on the Z axis, and an XYZ-piezoelectric displacement element is disposed in the second scanning unit 30. The position of the probe 12 on the XYZ triaxial is controlled because the height adjustment amplitude of the probe 12 on the Z axis is much smaller than its movement in the XY plane, but the invention is not limited in this way. Constructing a dual probe architecture can also be achieved in other ways.

When scanning with the atomic force microscope 1, it is first necessary to align the probes 11, 12. In this embodiment, the alignment is performed in two steps of coarse adjustment and fine adjustment. In the coarse adjustment, an image of the probes 11 and 12 is displayed by an optical microscope 60, and the first scanning unit 20 and the first control unit are controlled. The two scanning unit 30 moves the tips of the probes 11, 12 to a certain range to coarsely adjust the relative positions of the probe tips. Then, in the fine adjustment, the other probe 12/11 is scanned with the tip of one of the probes 11 and 12, for example, the tip of the probe 12 is scanned by the probe 11, and the two probes 11 are obtained. The relative positional relationship between 12, so that the relative position of the tip of the probe 11, 12 can be mobilized or used for subsequent interpretation of the data.

Next, adjusting an inclination angle of the two probes 11, 12 respectively is suitable for scanning a test piece 2. Please refer to FIG. 2, which shows a probe thereof, for example, a schematic diagram of the positional relationship between the probe 11 and a test strip 2. As can be seen from Fig. 2, the inclination angle of the probe 11 is preferably such that the side surface of the probe tip is attached to the side wall of the test piece 2, i.e., the ψ angle in the figure is zero. The other parameters shown in Fig. 2 are: σ is the side wall inclination angle of the test piece 2, α is the tip half angle of the probe 11, 1 is the length of the probe 11, the needle tip β is the rotation angle of the probe 11, h It is the thickness of the test piece 2, and p is the graphic width of the surface microstructure shape on the test piece 2. The probe tilt angle Φ satisfies the following relationship: Φ = σ + α + β - π, in which case the side of the probe tip can be attached to one side wall of the test strip 2, which can increase the effective scanning range of the probe tip. In the example of FIG. 2, the above relationship is satisfied such that the probe tip is scanned to the intersection of the right side wall and the bottom of the test piece 2 such that the right side of the tip of the probe 11 is attached to the right side wall of the test piece 2. The other probe 12 is preferably inclined to the opposite direction of the probe 11, as inclined to the left side in FIG. 2, preferably to satisfy the aforementioned relationship and tilted so that the probe tip is scanned to the left side wall and the bottom of the test piece 2. At the junction, the left side of the tip of the probe 12 is attached to the left side wall of the test piece 2.

However, it is considered that some of the test pieces 2 may be fragile or have a repeating microstructure disposed thereon. If the probes 11, 12 are tilted at a large angle, the tip of the probe may collide with a densely arranged microstructure in the vicinity during scanning. damage. In order to avoid such a situation, first determine whether the probe tilt angle Φ obtained by the above relation is obtained by the relationship of β-α-tan ^-1 (h/(hcot(σ)+p))≦σ+α+β-π Greater than β-α-tan ^-1 (h/(hcot(σ)+p)), and if so, set the inclination of the probe 11/12 to β-α-tan ^-1 (h/(hcot(σ)+p )) instead of σ+α+β-π. Therefore, after adjusting the probe tilt angle by this step, the probes 11, 12 are adapted to scan the particular test strip 2.

Next, the test piece 2 is scanned by a probe 11/12 to obtain a scanned data. In this embodiment, one of the probes 11, 12 is rotated to scan the test strip 2 in the opposite direction, wherein the probe is tilted at an acute angle to scan the test strip 2 from one side to the opposite side, The other probe having an angle of inclination of the probe is an obtuse angle, and the test piece 2 is scanned from the opposite side to the one side. For example, the probe 11 shown in FIG. 2 is scanned from left to right, and the probe 12 is scanned from right to left. After the scanning is completed, the data processing unit 40 receives the probe. Scanned data obtained by needles 11, 12.

The data processing unit 40 then combines the two pieces of scanned data from the probes 11, 12 to obtain the surface microstructure shape or micro-characteristics on the test piece 2 after the data has been interpreted. In the present embodiment, it is considered that the inclination angles of the probes 11, 12 are different and the scanning directions are different, so that they have different performances for the microstructure shapes of different slopes. For example, the tilt angle of the probe 11 is an acute angle and its scanning direction is from left to right, which has a poor judgment effect on the shape of the microstructure falling with a negative slope, and conversely, it is a shape of the microstructure that rises with a positive slope. , can be judged accurately. Therefore, when there is a positive slope between two consecutive scanning points, the scanning data obtained by the probe 11 having an acute angle and whose scanning direction is left to right is for analyzing the surface microstructure shape or micro characteristics. However, when there is a negative slope between successive two scanning points, the scanning data obtained by the right-to-left probe 12 is taken as an obtuse angle and its scanning direction is for analyzing the surface microstructure shape or micro-characteristic. The following formula is the data merge relationship: P _m ( t _k ) is the combined result of one of the two scanning data, S _i ( t _k ) is the slope between the two scanning points, k =0,1,...., m ,...,i For the numbering of these probes, i = 1 or 2, respectively, represents probe 11 and probe 12.

It can be known from the above that the atomic force microscope scanning method of the present invention is designed to obtain the surface microstructure or micro-characteristics on the test piece by controlling the inclination angle of the double probe and combining scanning data, and effectively improving the accuracy of the atomic force microscope. Sex.

The above description is based on a number of different embodiments of the invention, wherein the features may be implemented in a single or different combination. Therefore, the disclosure of the embodiments of the present invention is intended to be illustrative of the embodiments of the invention. Further, the foregoing description and the accompanying drawings are merely illustrative of the invention and are not limited. Variations or combinations of other elements are possible and are not intended to limit the spirit and scope of the invention.

Claims (6)

An atomic force microscope scanning method suitable for an atomic force microscope with dual probes, comprising: aligning the probes; respectively adjusting an inclination angle Φ of the probes for scanning a test piece, and by using an optical The microscope displays the images of the probes and the test strips for alignment; respectively, scanning the test strips with a probe to obtain a scan data; and combining the two scan data to obtain a surface microstructure shape or micro on the test strip The characteristic includes the following steps: when there is a positive slope between two consecutive scanning points, the inclination angle Φ of the probes is taken as an acute angle and the scanning direction is the scanning data obtained by the probe from left to right. Analyzing the surface microstructure shape or micro-characteristics; and when the two consecutive scanning points have a negative slope, the inclination angle Φ of the probes is obtuse and the scanning direction is obtained from the right-to-left probe. The scanned data is for analysis of its surface microstructure shape or micro-characteristics. The atomic force microscope scanning method according to claim 1, wherein the inclination angle Φ is obtained by the following relationship: the inclination angle Φ of the probe satisfies Φ=σ+α+β-π, and σ is one of the test pieces. The side wall inclination angle, α is the tip half angle of the probe, and β is the rotation angle of the probe. The atomic force microscope scanning method according to claim 1, wherein the inclination angle Φ is obtained in the following relationship: if β-α-tan ^-1 (h/(hcot(σ)+p))≦σ+α+ Β-π, the inclination angle Φ of the probe is set to be equal to β-α-tan ^-1 (h/(hcot(σ)+p)), otherwise, the inclination angle Φ of the probe is σ+α+β- π, σ is the inclination angle of one side wall of the test piece, α is the tip half angle of the probe, β is the rotation angle of the probe, and p is the graphic width of the surface microstructure shape on the test piece. The AFM scanning method of claim 1, wherein the step of aligning the probes further comprises: coarsely adjusting the probe tips by displaying an image of the probe tips The relative positions of the probes are scanned by the probes of the other probes to obtain the relative positional relationship between the probes to finely adjust the relative positions of the probe tips. The AFM scanning method of claim 1, wherein the step of scanning the test piece with a probe to obtain a piece of scanned data further comprises: moving one of the probes in turn to scan the opposite direction Audition. The atomic force microscope scanning method according to claim 5, wherein the step of combining the two scanning materials to obtain the surface microstructure shape or micro-characteristics on the test piece is performed according to the following relationship: For the result of combining the two scan data, S _i ( t _k ) is the slope between the two scan points, k =0, 1, . . . , m, . . . , i is the probe Number, i=1 or 2.