Abstract: Billion-pixel infrared detectors are an important direction for the development of next-generation infrared detectors, and the 8-inch high-uniform Hg_1-xCd_xTe thin film has become the most crucial component of this technology. The structure and layout of molecular beam epitaxy(MBE) effusion cells are key factors influencing the composition and thickness uniformity of Hg_1-xCd_xTe epitaxy films. This paper theoretically analyzes the beam flux generation and emission distribution of effusion cells based on requirements for large-area high-uniformity Hg_1-xCd_xTe epitaxial films. It simulates and calculates the impacts of effusion cell layout and the usage of source materials within the cells on the thickness uniformity of epitaxial thin films. This article takes a cylindrical channel effusion cell as an example and uses COMSOL Multiphysics to simulate the MBE growth process with different distances and different angles from the effusion cell of MBE, and the uniformity of the beam reaching the substrate is calculated. The results show that the beam flux decreases nearly linearly with source material consumption. The highest thickness uniformity is achieved when the angle is 46°; as the distance increases, the thickness uniformity becomes better, and after 300 mm, the thickness uniformity is within ±1.5%. This ensures the successful preparation of 8-inch highly uniform Hg_1-xCd_xTe thin film.