Surface activated bonding (SAB) is a technique that enables the direct bonding of dissimilar materials at room temperature. Since SAB does not require a heating process, it prevents thermal deformation and is widely applied in semiconductor bonding involving heterogeneous materials. The fast atom beam (FAB) source is commonly employed for surface-activated bonding. With the increasing diameter of semiconductor wafers, there is a growing demand for large-area and uniform irradiation. In this study, we developed an FAB source equipped with potential distribution control electrodes to achieve a broader and more uniform irradiation area. Simulations confirmed that the proposed structure generated a distinct potential distribution compared to conventional FAB sources, leading to modified ion acceleration characteristics. The performance of the developed FAB source was evaluated through an oxide layer removal test, demonstrating superior irradiation characteristics and enhanced uniformity. Additionally, the effect of aperture shape on the irradiation distribution was analyzed. These findings indicate that modifying the potential distribution enables control over irradiation characteristics and offers the potential to further expand the irradiation area. This study presents an approach for optimizing irradiation performance by regulating the internal potential distribution of the FAB source, contributing to advancements in FAB irradiation technology for semiconductor manufacturing.