High-gain hybrid photomultiplier based on micro-channel plate

Abstract

The invention relates to a high-gain hybrid photomultiplier based on a micro-channel plate. An MCP (micro-channel plate) is placed behind a photocathode to amplify photoelectrons generated by the photocathode, and the amplified electrons are accelerated under an external voltage, and the motion trail is restrained by the focusing electrode to ensure that high-energy electrons can bombard a wide bandgap semiconductor detector. A 6,000-20,000V negative high voltage can be loaded to the photocathode, and the voltage of the photocathode, the voltage of the MCP and the voltage of a focusing electrode can be flexibly adjusted through the ratio of three voltage dividing resistors in a voltage dividing circuit according to needs, thereby achieving the adjustment of the gain and time characteristics. The gain of the hybrid photomultiplier is not only limited to high gain, but also can be adjusted within a wide gain range (102-106) through the existence of the MCP or the multi-stage MCP, an external voltage value and a wide bandgap semiconductor detector structure, and different gain requirements can be met.

Description

technical field [0001] The invention belongs to the field of nuclear radiation detection, and relates to a high-gain hybrid photomultiplier tube based on a microchannel plate, which can be used for researches such as pulse radiation measurement and single particle detection. Background technique [0002] Scintillator-based detection methods have been widely used in radiation detection, spectroscopy research and other fields, and have made outstanding contributions. This is entirely dependent on the photomultiplier tube being able to convert and amplify the weak pulsed flash signal generated by the scintillator excited by radiation into a measurable electrical signal. Although semiconductor diodes are also used for the luminescence measurement of scintillators, the photomultiplier tube is still the most widely used device. Due to the wide statistical distribution of the pulse output amplitude of the traditional photomultiplier tube, the pulse amplitude spectrum measured by t...

AI Technical Summary

Problems solved by technology

In order to further increase the magnification of the hybrid photomultiplier tube, one is to increase the applied voltage value infinitely, which is obviously impractical; the other is to change the structure of the back-end semiconductor device, such as using an avalanche diode to further amplify the number of electrons , but because avalanche diodes are mostly made of silicon materials, they usually have large dark noise and poor radiation resistance, and their performance will deteriorate after long-term use, which is not conducive to maintaining the excellent performance of hybrid photomultiplier tubes.

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