Integrated measuring device for surface dielectric properties of solid insulating materials

Abstract

The invention discloses an integrated measuring device for surface dielectric properties of solid insulating materials. The device includes a secondary electronic measurement module, a sample stage module, a corona charging module, a surface potential measurement module and a vacuum / high pressure system; the secondary electronic measurement module includes an electronic gun and a collector; the electronic gun is arranged right above the collector, and the central axes of the electronic gun and the collector are on a same straight line; the sample stage module is provided with a sample flatform, and the bottom surface of the sample flatform is provided with sliding tracks in X, Y and Z axis directions; the corona charging module includes a high voltage electrode and a corona needle, and thehigh voltage electrode is connected to the corona needle; the surface potential measurement module includes a high voltage interface and a static probe, and the static probe is connected to the highvoltage interface; and the vacuum / high pressure system includes an outer cavity body, a gas interface, a vacuum interface, a gas cylinder and a vacuum pump, the gas interface and the vacuum interfaceare arranged on the wall of the outer cavity body and communicate with the outer cavity body, the gas cylinder is connected to the gas interface, and the vacuum pump is connected to the vacuum interface.

Description

technical field [0001] The invention relates to the technical field of measurement of surface charge characteristics of materials, in particular to a comprehensive measurement device for surface dielectric characteristics of solid insulating materials. Background technique [0002] The secondary electron emission coefficient, surface charge characteristics and charge traps on the surface of insulating materials are the key parameters reflecting the surface characteristics of materials. The surface secondary electron emission coefficient reflects the electron detachment ability of the material surface layer; the charge trap reflects the charge binding ability of the material surface layer; the surface charge is a comprehensive reflection of the charge accumulation and dissipation characteristics of the material surface. The three parameters do not exist in isolation, but are interrelated with each other. The current devices all measure one of the three parameters separately,...

AI Technical Summary

Problems solved by technology

The current devices measure one of the three parameters separately, and the measurement environment and measurement conditions are different, so there is a problem that the experimental data cannot be compared

At the same time, the measurement of a single parameter cannot truly and comprehensively reflect the dielectric properties of the insulating material surface, and can only reflect a specific process one-sidedly.

At present, most of the devices for measuring charge traps inject charges into the sample through corona, which can only measure the charge trap parameters on the surface of the material, but cannot measure the trap parameters at a certain depth.

[0003] The Chinese patent No. 201410022709.1 discloses a secondary electron emission coefficient measurement device based on a hemispherical collector structure. The device distinguishes true secondary electrons from backscattered electrons through a multi-layer spherical mesh screen, and passes through a pulsed electron beam. To reduce the impact of dielectric material surface charge on secondary electron emission, the device mainly measures the secondary electron emission characteristics of materials in a vacuum environment, and cannot measure the surface charge and trap parameter distribution of materials

The Chinese patent with the patent number 201410023001.8 discloses a measuring device for the secondary electron emission coefficient of the flat plate collector. The device provides a rotating sample stage, and the sample is rotated at a certain angle before and after each measurement to avoid multiple measurements at the same position. In order to reduce the influence of the surface charge of the insulating material on the secondary electron emission coefficient, but there is a large gap between the collector and the sample, so it is difficult to guarantee the secondary electron collection efficiency; the Chinese patent No. 201010617890.2 discloses A test device for distinguishing secondary electrons from backscattered electrons. The device discloses a hemispherical collection structure composed of collectors and retardation grids. By applying different voltages to the retardation grids, the secondary electrons and backscattered The distinction of scattered electrons and the energy spectrum analysis of secondary electrons, but this device can only be used for the measurement of metal materials, and the accumulation of material surface charges will seriously affect the measurement results when measuring insulating materials; these two devices can only measure the secondary of materials Sub-electronic properties, unable to measure the surface charge and trap parameter distribution of the material

[0004] The Chinese patent No. 2009100231880 discloses an automatic measurement device for the surface charge distribution of a solid medium. The device uses an electrostatic probe to measure the surface charge of insulating materials, and can measure the two-dimensional charge distribution through a two-dimensional motion platform, but the device only Can measure surface charge in a fixed environment and cannot measure secondary electron emission properties of materials

[0005] The Chinese patent No. 2014104587908 discloses a solid dielectric material trap parameter acquisition system. The device uses three-electrode corona charging to inject charges into the sample, heats the sample through the heating system, and the electrostatic probe measures the surface charge decay. According to the surface Calculate the trap parameters of the sample based on the charge decay. The device can only measure the charge traps on the surface of the material, but cannot measure the trap parameters at a certain depth; at the same time, the device cannot measure the secondary electron emission characteristics of the material

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