Plasma surface in teractions are an important aspect of spacecraft design. Due to the presence of negatively charged surfaces, a few slow ions present in the plume region of an ion thruster can enter the back-flow region of the thruster and interact with the surface of spacecraft1. This interaction is important especially for the solar panels present in this backflow region of ion thrusters. The ions accelerating towards the spacecraft can cause surface sputtering on dielectric protective coating present on the solar panel surfaces. Additionally, other elements such as Molybdenum which is present in the ion-plume may be deposited on the solar panels and reduce their energy efficiency2, In this work, we will perform a three-dimensional numerical study of ion thruster plume plasma interactions with a surface.