Ultra-low background alpha ionization chamber

Abstract

The invention belongs to the technical field of radioactivity measurement and discloses an ultralow background alpha ionization chamber for measuring an ultralow background alpha sample. The ionization chamber comprises a cylindrical cavity and a shielding body, wherein the cavity is positioned in the shielding body and positioned in the central position at the bottom of the shielding body; a circular anode and an annular protection pole are arranged on the lower surface of the top of the cavity, an anode and the protection pole have the same working voltage and are used as collection poles, the anode, the protection pole and the position of the center of a circle of the top of the cylindrical cavity are consistent, and the protection pole is positioned on the outer side of the anode and is insulated with the anode; a sample support is arranged at the bottom of the cavity and used as a cathode at the same time; the distance between the anode and the cathode is 2-5 times the range of alpha particles in working gas of the ionization chamber at normal pressure. The ionization chamber has the characteristics that the ionization chamber can discriminate and eliminate alpha emissivity of material of the ionization chamber and be used for measuring the ultralow background alpha sample.

Description

technical field [0001] The invention belongs to the technical field of radioactivity measurement, and in particular relates to an ultra-low background alpha ionization chamber for measuring ultra-low background alpha samples. Background technique [0002] The demand for low background or even ultra-low background α measurement is increasing in environmental monitoring, basic physics experiments, new material production, especially in the production of microelectronic component packaging materials. Especially as the semiconductor production process enters the finer nanometer level, the operating voltage becomes lower, and the soft error (Soft Error) caused by ionizing radiation will increase exponentially under this condition. In order for this error rate not to affect the performance of electronic products, the alpha radiation in the packaging material is required to be as small as possible. Therefore, there is an urgent need for corresponding ultra-low background α measuri...

AI Technical Summary

Problems solved by technology

This method has reached its limit, and it is still difficult to meet the demand for the measurement of ultra-low background α samples

Similarly, for semiconductor detectors, in addition to the α background of the detector material itself, it is also affected by cosmic rays, and it is difficult to meet the needs of ultra-low background measurement

At present, there is no ultra-low background alpha ionization chamber that can screen and reject the alpha emission rate of the detector material itself

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