Design and construction of electron impact ion source controller for Mass spectrometer system

Abstract

The resolution of a mass spectrometer is dependent directly on the strength of the output ion and its energy. The number of produced ions depends on the current and the energy of the electron beam. One task of the electronic collision source control circuit is to regulate the current and energy of the electron beam to achieve optimal resolution. Parameters such as the stabilization of the electron beam current and its energy, the precise change of the electrical potential of the lens, and the ion source electrodes are very important in the construction of the electronic collision source control circuit. In this paper, the ion source control circuit was designed and built and stabilize the electron emission current, beam energy, and electrical potential of points. This controller circuit was installed and tested on the Varian MAT 44 mass spectrometer. The stabilization of the current and energy of the electron in this control circuit was measured to be less than 1%.

Keywords

• electron impact ion source controller
• electron emission current stabilizer
• mass spectroscopy