A focused ion gun

Abstract

The invention discloses an ion gun structure used for thinning solid materials by an ion thinning instrument. It includes a first cathode, a concave anode and a second cathode; the voltage between the first cathode and the concave anode is controlled between 0‑2kV, and the voltage between the concave anode and the second cathode is 0‑ Between 6kV. There is a small hole at one end of the first cathode for argon gas to enter between the first cathode and the concave-shaped anode. Under the action of the electric field, the argon gas is ionized to form positive ions Ar+, and enters between the concave anode and the second cathode. There is a hole with a diameter of 1 mm to 2 mm in the center of the concave-shaped anode. One side is covered by an insulating layer, and the other side is a concave-hole metal surface. Under the action of the high-voltage electric field between the second cathodes, Ar+ is accelerated and forms a substantially parallel ion beam, which rushes out of the ion gun to thin the sample. The ion gun of the invention has good focusing performance, and when thinning a solid sample, the temperature rise of the sample is small.

Description

technical field [0001] The invention belongs to the field of instruments for material science research, and more particularly relates to a focused ion gun. Background technique [0002] The development of material science is inseparable from advanced material sample preparation and analysis methods. The ion thinning instrument is a kind of mechanical impact on the surface of the material by using high-energy ion beam to thin the solid sample to a thickness of 2000 angstroms for transmission. The internal microstructure and composition of materials are observed under electron microscope (TEM), so as to research and develop new materials. [0003] The ion gun is a key component of the ion thinning instrument, and the focusing ability of the ion gun is one of the key factors that determine the performance of the ion thinning instrument. The structure of the traditional ion gun is generally composed of positive and negative electrodes, and an electric field of 8kV to 10kV or ev...

AI Technical Summary

Problems solved by technology

The higher the electric field voltage, the higher the ion beam speed, the stronger the thinning ability of the sample. However, when the electric field voltage exceeds 8kV, the temperature of the sample will easily rise when the ion thins the sample, which will cause the phase change of the material and affect the effect on the material. observation and analysis

The ionization voltage of the other half of the argon gas Ar is between 0-4kV. When the voltage exceeds 4kV, the ionization energy is too high due to the high ionization voltage, which is prone to unstable discharge phenomenon. A small amount of impurities are more prone to discharge under high voltage, resulting in the inability to generate a stable ion beam

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