In this work, we report the contact potential difference measured by Kelvin probe force microscopy of phosphorus-doped Si/MoS2/graphene and Si/MoS2/GO with different thicknesses deposited using micro drop casting and chemical vapor deposition. Doping with 15% phosphorus increased the surface potential of the layers. The readings obtained were from -722.27 to +340.46, showing that layer orientation is equally important as layer thickness when designing multilayer two-dimensional systems where surface potential is considered. The number of layers is essential to forming metal contacts for fabricating future MoS2-GO-based devices.