A method for preparing microscale tungsten needle tips of different aspect ratios using a direct current power supply
Micron-sized tungsten needle tips with different aspect ratios were prepared by direct current electrochemical etching, which solved the problem of instability in the preparation of high-precision needle tips, realized independent production, reduced costs, and met the needs of high-precision microscopes.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- WUXI NASKAI SEMICON TECH CO LTD
- Filing Date
- 2026-05-20
- Publication Date
- 2026-07-31
AI Technical Summary
The inability of China to independently produce high-precision atomic force microscope and scanning tunneling microscope tips has led to reliance on imported consumables, resulting in high costs and impacting testing results. Existing equipment cannot meet the ever-increasing production requirements.
Electrochemical etching was performed using a DC regulated power supply. Micron-sized tungsten needle tips with different aspect ratios were prepared by utilizing the characteristics of the DC regulated power supply. The aspect ratio and radius of curvature of the needle tips were controlled by adjusting the voltage and current parameters, resulting in tungsten needle tips with a radius of curvature of less than 3 μm.
It has achieved stable preparation of high-precision tungsten needle tips, meeting different needs, breaking the dependence on imported consumables, reducing costs, and improving the equipment's independent production capabilities.
Smart Images
Figure CN122487701A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a method for preparing micron-sized tungsten needle tips with different aspect ratios, and particularly to a method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply. Background Technology
[0002] Atomic force microscopes and scanning tunneling microscopes are important modern scientific research tools, playing an indispensable role in many fields such as materials, biology, and semiconductors. Among them, high-precision probes are essential high-value consumables for these devices. Due to technological reasons, they cannot be produced domestically and must be imported from abroad, resulting in long trade cycles and high costs.
[0003] Meanwhile, as important failure analysis equipment in the semiconductor industry, the tips of these two microscopes gradually become dull with use, affecting the final test results.
[0004] Due to time constraints, existing domestic processing equipment cannot meet the ever-increasing production requirements. Most of the atomic force microscopes and scanning tunneling microscopes used in China are imported, which further restricts the independent production of the domestic semiconductor industry and is greatly hampered. There is an urgent need to develop suitable high-precision probes to break the monopoly.
[0005] Therefore, there is a particular need for a method to prepare micron-sized tungsten needle tips with different aspect ratios using a DC power supply in order to solve the aforementioned existing problems. Summary of the Invention
[0006] The purpose of this invention is to provide a method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply. This method effectively solves the problem of instability in the preparation of small-diameter material needle tips, addresses the shortcomings of existing technologies, ensures good appearance and morphology, and allows adjustment of the needle tip aspect ratio to meet different needs.
[0007] The technical problem solved by this invention can be achieved by the following technical solutions:
[0008] A method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply includes the following steps:
[0009] S1. Use a DC regulated power supply as the power generation device, and use a tungsten wire with a cross-sectional diameter of less than 400μm as the corrosion body. Immerse the tungsten wire in the electrochemical corrosion solution, keeping the tungsten wire perpendicular to the surface of the electrochemical corrosion solution.
[0010] S2. Using an external DC regulated power supply, a tungsten wire is used as the anode and a stainless steel open cylindrical sleeve in the corrosion container is used as the cathode for electrochemical corrosion processing. When the current reading on the DC regulated power supply is 0, the power supply is quickly cut off to complete the electrochemical corrosion processing and form a tungsten needle tip with an aspect ratio of 0.5-3 and a radius of curvature of less than 3μm.
[0011] In a preferred embodiment of the present invention, the DC regulated power supply is a UTP1306S type DC regulated power supply.
[0012] In a preferred embodiment of the present invention, the voltage of the DC regulated power supply is 3-10V and the current is 0.1-0.6A.
[0013] In a preferred embodiment of the present invention, the electrochemical corrosion solution is a sodium hydroxide solution with a concentration of 3-8 mol / L.
[0014] In a preferred embodiment of the present invention, the tungsten wire is immersed in the electrochemical corrosion solution to a depth of 0.5-5 mm.
[0015] In a preferred embodiment of the present invention, the reaction time of the electrochemical corrosion process is 2-8 minutes.
[0016] In a preferred embodiment of the present invention, during the electrochemical etching process, the relationship between the current parameter of the DC regulated power supply and the length-to-diameter ratio of the needle tip is as follows: when the current parameter is constant, the smaller the voltage, the larger the length-to-diameter ratio of the needle tip; the larger the voltage, the smaller the length-to-diameter ratio of the needle tip.
[0017] The present invention provides a method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply. Compared with existing technologies, this method utilizes the characteristics of a DC regulated power supply in electrochemical corrosion to prepare hyperbolic tungsten needle tips. By adjusting the corresponding electrical parameters of the DC regulated power supply, needle tips with different aspect ratios can be prepared to obtain tungsten needle tips that meet the requirements. The needle tips prepared by this method have an aspect ratio of 0.5-3 and a radius of curvature of less than 3 μm, effectively solving the problem of instability in the preparation of small-diameter material needle tips and achieving the objective of the present invention.
[0018] The features of the present invention can be clearly understood by referring to the drawings and the following detailed description of preferred embodiments. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the needle tip morphology obtained by electrochemical corrosion using low voltage parameters according to the present invention.
[0020] Figure 2 This is a schematic diagram of the needle tip morphology obtained by electrochemical corrosion using high voltage parameters according to the present invention;
[0021] Figure 3 This is a schematic diagram of the needle tip morphology obtained by electrochemical corrosion using higher voltage parameters according to the present invention.
[0022] Figure 4 This is a schematic diagram of another needle tip morphology for electrochemical corrosion using higher voltage parameters according to the present invention. Detailed Implementation
[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0024] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0025] It should be noted that similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, all directional indications in this application (such as up, down, left, right, front, back, bottom, etc.) are only used to explain the relative positional relationships and movements between components in a specific orientation (as shown in the figures). If the specific orientation changes, the directional indication will also change accordingly. Furthermore, descriptions involving "first," "second," etc., in this application are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated.
[0026] The method of the present invention for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply includes the following steps:
[0027] S1. Use a DC regulated power supply as the power generation device, and use a tungsten wire with a cross-sectional diameter of less than 400μm as the corrosion body. Immerse the tungsten wire in the electrochemical corrosion solution, keeping the tungsten wire perpendicular to the surface of the electrochemical corrosion solution.
[0028] S2. Using an external DC regulated power supply, a tungsten wire is used as the anode and a stainless steel open cylindrical sleeve in the corrosion container is used as the cathode for electrochemical corrosion processing. When the current reading on the DC regulated power supply is 0, the power supply is quickly cut off to complete the electrochemical corrosion processing and form a tungsten needle tip with an aspect ratio of 0.5-3 and a radius of curvature of less than 3μm.
[0029] In this invention, the DC regulated power supply is a UTP1306S type DC regulated power supply.
[0030] In this invention, the voltage of the DC regulated power supply is 3-10V and the current is 0.1-0.6A.
[0031] In this invention, the electrochemical corrosion solution is a sodium hydroxide solution with a concentration of 3-8 mol / L.
[0032] In this invention, the tungsten wire is immersed in the electrochemical corrosion solution to a depth of 0.5-5 mm.
[0033] In this invention, the reaction time for the electrochemical corrosion process is 2-8 minutes.
[0034] In this invention, during the electrochemical corrosion process, the relationship between the current parameter of the DC regulated power supply and the length-to-diameter ratio of the needle tip is as follows: when the current parameter is constant, the smaller the voltage, the larger the length-to-diameter ratio of the needle tip; the larger the voltage, the smaller the length-to-diameter ratio of the needle tip.
[0035] Example 1
[0036] The specific process of the method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply according to the present invention is as follows:
[0037] After setting a fixed current (0.1-0.5A), set a lower voltage (3-5V). Before connecting the cathode and anode, turn on the DC regulated power supply to stabilize the equipment. Then connect the wires to the cathode and anode to begin electrochemical corrosion. The concentration of the electrochemical corrosion solution is 3-8 mol / L. When the displayed current of the DC regulated power supply reaches 0, immediately turn off the power supply to form a tungsten needle tip with an aspect ratio of 2-3 and a radius of curvature of 1-3 μm. The needle tip morphology is as follows. Figure 1 As shown.
[0038] Example 2
[0039] The specific process of the method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply according to the present invention is as follows:
[0040] After setting a fixed current (0.1-0.5A), set a high voltage (8-10V). Before connecting the cathode and anode, turn on the DC regulated power supply to stabilize the equipment. Then connect the wires to the cathode and anode to begin electrochemical corrosion. The concentration of the electrochemical corrosion solution is 3-8 mol / L. When the displayed current of the DC regulated power supply reaches 0, immediately turn off the power supply to form a tungsten needle tip with an aspect ratio of 0.5-1 and a radius of curvature of 1-3 μm. The needle tip morphology is as follows. Figure 2 As shown.
[0041] Example 3
[0042] The specific process of the method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply according to the present invention is as follows:
[0043] After setting a fixed current (0.1-0.5A), set a relatively high voltage (5-6V). Before connecting the cathode and anode, turn on the DC regulated power supply to stabilize the equipment. Then connect the wires to the cathode and anode to begin electrochemical corrosion. The concentration of the electrochemical corrosion solution is 3-8 mol / L. When the displayed current of the DC regulated power supply reaches 0, immediately turn off the power supply to form a tungsten needle tip with an aspect ratio of 1.5-2 and a radius of curvature of 1-3 μm. The needle tip morphology is as follows. Figure 3 As shown.
[0044] Example 4
[0045] The specific process of the method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply according to the present invention is as follows:
[0046] After setting a fixed current (0.1-0.5A), set a relatively high voltage (7-8V). Before connecting the cathode and anode, turn on the DC regulated power supply to stabilize the equipment. Then connect the wires to the cathode and anode to begin electrochemical corrosion. The concentration of the electrochemical corrosion solution is 3-8 mol / L. When the displayed current of the DC regulated power supply reaches 0, immediately turn off the power supply to form a tungsten needle tip with an aspect ratio of 1-1.5 and a radius of curvature of 1-3 μm. The needle tip morphology is as follows. Figure 4 As shown.
[0047] This invention discloses a method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply. By controlling the voltage, current, and other electrical parameters of the DC regulated power supply during the electrochemical corrosion process, the corrosion rate and morphology of the tungsten wire are adjusted. In DC mode, the tungsten wire is more likely to exhibit a hyperbolic profile during electrochemical corrosion, meeting the morphology requirements of various high-precision needle tips, such as STM needle tips. Voltage and current, as the most direct factors in regulating the corrosion rate, can be adjusted to meet different needs based on the required aspect ratio. The needle tips prepared using this method effectively solve the problem of instability in the preparation of small-diameter material needle tips, ensuring good appearance and achieving the objectives of this invention.
[0048] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as defined by the appended claims and their equivalents.
Claims
1. A method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply, characterized in that, Includes the following steps: S1. Use a DC regulated power supply as the power generation device, and use a tungsten wire with a cross-sectional diameter of less than 400μm as the corrosion body. Immerse the tungsten wire in the electrochemical corrosion solution, keeping the tungsten wire perpendicular to the surface of the electrochemical corrosion solution. S2. Using an external DC regulated power supply, a tungsten wire is used as the anode and a stainless steel open cylindrical sleeve in the corrosion container is used as the cathode for electrochemical corrosion processing. When the current reading on the DC regulated power supply is 0, the power supply is quickly cut off to complete the electrochemical corrosion processing and form a tungsten needle tip with an aspect ratio of 0.5-3 and a radius of curvature of less than 3μm.
2. The method of claim 1, wherein the tungsten microneedle with different aspect ratios is prepared using a direct current power supply. The DC regulated power supply is a UTP1306S type DC regulated power supply.
3. The method of claim 1, wherein the tungsten microneedle with different aspect ratios is prepared using a direct current power supply. The voltage of the DC regulated power supply is 3-10V and the current is 0.1-0.6A.
4. The method of claim 1, wherein the tungsten microneedle with different aspect ratios is prepared using a direct current power supply. The electrochemical corrosion solution is a sodium hydroxide solution with a concentration of 3-8 mol / L.
5. The method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply as described in claim 1, characterized in that, The tungsten wire is immersed in the electrochemical corrosion solution to a depth of 0.5-5 mm.
6. The method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply as described in claim 1, characterized in that, The reaction time for the electrochemical corrosion process is 2-8 minutes.
7. The method for preparing micron-sized tungsten needle tips with different aspect ratios using a DC power supply as described in claim 1, characterized in that, During the electrochemical etching process, the relationship between the current parameter of the DC regulated power supply and the length-to-diameter ratio of the needle tip is as follows: when the current parameter is constant, the smaller the voltage, the larger the length-to-diameter ratio of the needle tip; the larger the voltage, the smaller the length-to-diameter ratio of the needle tip.