Combined scanning probe microscope body with common stepping unit

Abstract

The invention relates to a combined scanning probe microscope body with a common stepping unit, which is characterized by comprising an outer frame, a base, a first scanning unit, a first probe support, a stepping unit and a second probe support, the outer frame is hollow, the base is fixed at the top of the outer frame, one end of the first scanning unit is fixed on the base, and the other end of the first scanning unit is fixed on the first probe support. The first probe support is arranged at one end of the stepping unit, the first probe support is arranged at the other end of the stepping unit, the stepping unit is arranged in the outer frame, the first sample table is arranged at the top of the stepping unit, the second sample table is arranged at the bottom of the stepping unit, and the second probe support is fixed at the bottom of the outer frame. The combined type scanning probe microscope comprises two testing structures of the scanning probe microscope, the approaching process and the needle withdrawing process of the two testing structures share the same stepping unit, and the microscope is compact in structure, high in rigidity and suitable for extreme environment testing of a low-temperature and high-intensity magnetic field.

Description

Technical Field

[0001] The invention belongs to the technical field of scanning probe microscopes, and in particular relates to a combined scanning probe microscope body suitable for a co-stepping unit. Background Art

[0002] Scanning probe microscopy has become a cutting-edge tool for exploring surface science due to its excellent atomic resolution and manipulation and handling capabilities at the atomic scale. It has a wide variety of types, including scanning tunneling microscopes, magnetic force microscopes, and atomic force microscopes. With the continuous advancement of science and technology and the in-depth development of traditional science, the application of scanning probe microscopes has surpassed conventional conditions and expanded to extreme environments such as extremely low temperatures and ultra-strong magnetic fields when exploring the properties of materials. Research under these extreme conditions can provide us with a deeper understanding of the nature of matter. Scanning probe microscope imaging usually requires independent cavity testing, and the cost of doing so is also huge, because first of all, whether it is a scanning tunneling microscope, a magnetic force microscope or an atomic force microscope, its commercial price is extremely expensive. If you want to buy these scanning probe microscopes at the same time, it will cost a huge amount of money. And under extreme test conditions (such as extremely low temperatures and strong magnetic fields), the test requires these scanning probe microscopes to be placed in the cavity one by one. This process not only causes the loss of resources such as liquid helium, but also consumes a lot of experimental time. The design of the combined scanning probe microscope integrates the functions of different scanning probe microscopes into the same mechanical structure, making it possible to perform multiple imaging tests in the same cavity and environment, significantly reducing the time and resource consumption during the experiment, thereby improving experimental efficiency and providing experimenters with a more convenient and efficient research method.

[0003] In the mechanical design of the combined scanning probe microscope, first, the diameter of the mirror body must meet the aperture limitation of the high-intensity magnetic field environment (for example, the room temperature aperture of the center of a 27T water-cooled magnet is only 32 mm). Secondly, because the microscope integrates multiple test functions, each function must not interfere with each other during operation and measurement imaging. In addition, the stepper unit used in the combined scanning probe microscope needs to be specially considered in the design to reduce its cross-coupling error and scanning range error in sample scanning imaging or nano-operation. These error factors will significantly affect the quantitative analysis accuracy of imaging and the positioning accuracy of the probe in nano-operation. Summary of the invention

[0004] The purpose of the present invention is to design a combined scanning probe microscope with a co-stepping unit based on the combined scanning probe microscope concept proposed above, which can realize the testing of multiple scanning probe microscopes on the same microscope body.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A combined scanning probe microscope body with a stepping unit, characterized in that it includes an outer frame, a base, a first scanning unit, a first probe bracket, a stepping unit and a second probe bracket, the outer frame is hollow inside, the base is fixed to the top of the outer frame, one end of the first scanning unit is fixed to the base, the first probe bracket is fixed to the other end of the first scanning unit, the stepping unit is placed inside the outer frame, the first sample stage is placed on the top of the stepping unit, the first sample stage corresponds to the first probe bracket, the stepping unit and the first scanning unit, the first probe bracket, the first probe, the first sample stage and the outer frame constitute a test structure suitable for the first scanning probe microscope, the second sample stage is placed at the bottom of the stepping unit, the second probe bracket is fixed to the bottom of the outer frame, the stepping unit is also a second scanning unit, and the stepping unit and the second probe bracket, the second probe, the second sample stage and the outer frame constitute a test structure suitable for the second scanning probe microscope.

[0007] Preferably, the stepping unit is a common stepping unit for the approach and retraction processes of the first scanning probe microscope and the second scanning probe microscope.

[0008] Preferably, the stepping unit includes a piezoelectric element, a fixing ring, a sliding rod, a sleeve and a spring sheet. A fixing ring is provided at the top of the outer wall of the piezoelectric element, and the fixing ring is used to fix the piezoelectric element to the middle of the outer frame. The sleeve is fixed to the bottom of the inner wall of the second scanning unit, and the sliding rod is directly inserted into the sleeve. The spring sheet squeezes the sliding rod against the inner wall of the sleeve in the horizontal direction, and the sliding rod slides axially along the inner wall of the sleeve under the deformation of the piezoelectric element.

[0009] Preferably, the stepping unit cannot perform a stepping function and a scanning function simultaneously, and its stepping function is utilized in the first scanning probe microscope structure, and its stepping function and scanning function are utilized in the second scanning probe microscope structure.

[0010] Preferably, the first probe holder and the first sample stage are interchangeable in position, and the first probe holder can be placed on the top of the stepping unit, and the first sample stage can be placed at one end of the first scanning unit.

[0011] Preferably, the first scanning probe microscope is a scanning tunneling microscope.

[0012] Preferably, the second scanning probe microscope may be a magnetic force microscope or an atomic force microscope.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] (1) The mirror body of the present invention realizes a co-stepping unit during the testing process of different scanning probe microscopes. This design makes the mechanical structure of the mirror body more compact and stable, effectively reduces the size of the mirror body design, and enables it to adapt to the requirements of high-field test apertures. The effective combination of different scanning probe microscopes reduces the manufacturing cost of the mirror body. There is no need to switch the mirror body back and forth during the low-temperature test process, which reduces the loss of resources and the test time.

[0015] (2) Both ends of the mirror body of the present invention can be respectively applied to different scanning probe microscope tests, effectively isolating the mutual influence during the testing process of different microscopes. Scanning tunnel microscopes, magnetic force microscopes and atomic force microscopes need to maintain extremely high mechanical stability during the testing process. Any slight vibration of the scanning tunnel microscope during imaging may destroy the stability of the tunnel junction and affect the imaging quality. During the scanning process, both the magnetic force microscope and the atomic force microscope use the interaction force between the probe and the sample surface to form an image, which may produce certain mechanical vibrations. Testing them separately can avoid the mutual interference that may occur during their operation and ensure the accuracy and reliability of their respective test results.

[0016] (3) In the design of the stepping unit of the present invention, the spring sheet and the slide bar clamp have a larger contact area, which makes it more stable and less prone to sliding and offsetting when the piezoelectric tube deforms to drive the slide bar to move, and can effectively isolate the movement between the X-axis and the Y-axis, thereby reducing cross-coupling errors. Especially under high-field test conditions, the appropriate clamping force will make the slide bar less affected by the magnetic field torque, which is beneficial to the approach and withdrawal of the stepping unit during the test. In addition, during the magnetic force microscope and atomic force microscope test scanning process, since the stepping unit needs to be used for scanning, the spring sheet is used to clamp the slide bar at the magnetic force microscope and atomic force microscope test end when the stepping unit is designed, which increases the rigidity of the piezoelectric element and its supporting structure, can reduce the interference caused by external vibration, and thus improve the stability and accuracy of the scanning.

[0017] (4) The second probe bracket of the present invention is designed with an elliptical notch. The appropriate notch position enables the cantilever beam and the sample of the second probe to be located at the center of the notch in the vertical direction, which is beneficial for using a microscope to locate the tip of the cantilever beam and some tiny samples to be tested together through the notch when conducting magnetic sample testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a diagram of the overall mechanical structure of the combined scanning probe microscope.

[0019] Figure 2 This is a cross-sectional mechanical structure diagram of the combined scanning probe microscope.

[0020] Figure 3This is a schematic diagram of the first scanning probe microscope test in the combined scanning probe microscope.

[0021] Figure 4 This is a schematic diagram of the second scanning probe microscope test in the combined scanning probe microscope. Specific implementation plan

[0022] The technical solution of the present invention will be explained in detail and clearly with reference to the accompanying drawings of the embodiments of the present invention. Without inventive work, other implementation methods that can be derived by those skilled in the art based on these embodiments all belong to the protection scope of the present invention.

[0023] See attached Figure 1 The combined scanning probe microscope body structure of the present invention includes two scanning probe microscope test structures.

[0024] Embodiment 1: Stepping unit structure

[0025] See attached Figure 2 The stepping unit used in the present invention is integrated into a single microscope body to provide the required approach and retreat functions for two different types of scanning probe microscopes. The stepping unit includes a piezoelectric element, a fixing ring, a sliding rod, a sleeve and a spring sheet. The sleeve is fixed to the top of the inner wall of the piezoelectric element. The spring sheet squeezes the sliding rod against the inner wall of the sleeve in the horizontal direction. The sliding rod slides axially along the inner wall of the sleeve under the deformation of the piezoelectric element. The mirror body needs to be suspended vertically during testing. At this time, if the piezoelectric element is not driven by an external signal, the friction between the spring sheet and the sliding rod must be greater than the gravity of the sliding rod itself; when the stepping unit moves downward, the outer electrode of the piezoelectric element applies a reverse pulse voltage to make it extend rapidly, and the piezoelectric element can push the sliding rod downward; when the stepping unit moves upward, the outer electrode of the piezoelectric element applies a positive pulse voltage to make it contract rapidly, and the piezoelectric element can pull the sliding rod upward.

[0026] Example 2: Test structure suitable for scanning tunneling microscope

[0027] See attached Figure 3 , a test structure suitable for a scanning probe microscope is formed by the stepping unit described in Example 1, as well as a first scanning unit, a first probe holder, a first probe, a first sample stage and a window at the upper end of the outer frame. One end of the first scanning unit is fixed to the top of the outer frame with a base, and the other end is a free end fixed to the first probe holder for testing. A first sample stage is placed at the top of the stepping unit relative to the first probe holder. When the stepping unit is driven upward, the sample and the first probe approach each other and gradually enter the sample tunnel junction range to form a tunnel current. The external electrode of the first scanning unit is driven by the applied voltage signal to perform a small range of scanning or imaging; when the stepping unit is driven downward, the first probe gradually moves away from the sample tunnel junction to achieve needle withdrawal.

[0028] Example 3: Test structure suitable for magnetic force microscope and atomic force microscope

[0029] See attached Figure 4 The stepping unit, the second sample stage, the second probe base, the second probe and the lower window of the outer frame described in the first embodiment constitute a test structure suitable for magnetic force microscope and atomic force microscope. The second sample stage is placed at the bottom of the stepping unit, and the second probe base is placed at the bottom of the outer frame and fixed to it by titanium screws. When the stepping unit is driven downward, the sample and the second probe gradually approach each other and a torque is generated. Since the imaging range of magnetic force microscope and atomic force microscope is large, the stepping unit structure can be used for scanning imaging.

Claims

1. A combined scanning probe microscope body with a common stepping unit, characterized in that The invention comprises an outer frame (1), a base (2), a first scanning unit (3), a first probe support (4), a stepping unit (11) and a second probe support (10); the outer frame (1) is hollow inside; the base (2) is fixed on the top of the outer frame (1); one end of the first scanning unit (3) is fixed on the base (2) and the other end is provided with the first probe support (4); the stepping unit (11) is arranged inside the outer frame (1); the first sample stage (7a) is arranged on the top of the stepping unit (11); the stepping unit (11) and the first scanning unit are connected to each other. The first probe holder (3), the first probe (4), the first probe (5), the first sample stage (7a) and the outer frame (1) constitute a test structure suitable for a first scanning probe microscope; the second sample stage (7b) is arranged at the bottom of the stepping unit (11); the second probe holder (10) is fixed at the bottom of the outer frame (1); the stepping unit (11) is also a second scanning unit; the stepping unit (11) and the second probe holder (10), the second probe (9), the second sample stage (7b) and the outer frame (1) constitute a test structure suitable for a second scanning probe microscope.

2. The combined scanning probe microscope body of the co-stepping unit according to claim 1, characterized in that: The stepping unit (15) is a stepping unit shared by the first scanning probe microscope and the second scanning probe microscope.

3. The combined scanning probe microscope body of the co-stepping unit according to claim 1, characterized in that: The stepping unit comprises a piezoelectric element (15), a fixing ring (11), a sliding rod (8), a sleeve (12) and a spring sheet (13); a fixing ring (11) is provided at the top of the outer wall of the piezoelectric element (15); the fixing ring (11) is used to fix the piezoelectric element (15) inside the outer frame (1); the sleeve (12) is fixed to the bottom of the inner wall of the piezoelectric element (15); the spring sheet (13) presses the sliding rod (8) against the inner wall of the sleeve (12) in the horizontal direction; the sliding rod (8) slides axially along the inner wall of the sleeve (12) under the deformation of the piezoelectric element (15).

4. The combined scanning probe microscope body of the co-stepping unit according to claim 1, characterized in that: The stepping unit (11) cannot perform the stepping function and the scanning function at the same time.

5. The combined scanning probe microscope body of the co-stepping unit according to claim 1, characterized in that: The positions of the first probe support (4) and the first sample stage (7a) are interchangeable.

6. The combined scanning probe microscope body of the co-stepping unit according to claim 1, characterized in that: The first scanning probe microscope is a scanning tunneling microscope.

7. The combined scanning probe microscope body of the co-stepping unit according to claim 1, characterized in that: The second scanning probe microscope may be a magnetic force microscope or an atomic force microscope.

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