Influence of extraction voltage on electrons and ions behavior characteristics

The characteristics of the extracted ion current have a significant impact on the design and testing of ion source performance. In this paper, 2D3V particle in cell (2D3V PIC) method is utilized to simulate plasma motion and ion extraction characteristics under various initial plasma velocity distributions and extraction voltages in a Cartesian coordinate system. The plasma density is in the order of 1015 m-3~1016 m-3 and the extraction voltage is in the order of 100 V~1000V. The study investigates the impact of various extraction voltages on the velocity and density distributions of electrons and positive ions, and analyzes the influence of different initial plasma velocity distributions on the extraction current. The simulation results revealed that the main reason for the variation of extraction current is the space charge force formed by the relative aggregation of positive and negative net charges. This lays the foundation for a deeper understanding of extraction beam characteristics.