A method for controlling any of a responsivity, response time, and trap characteristics of a two-dimensional (2D) material on a self-assembled monolayers (SAMs) device, the method including modifying a surface of an oxide substrate, in an atomic scale, to create the 2D material, wherein the modifying the surface includes modifying a level of impurities trapped in the surface and a doping level of the surface, and forming charge carrier traps at the surface, wherein a capture rate and an emission rate of the charge carrier is influenced by an exposure to a light signal, and wherein the exposure to the light signal further changes the doping level of the surface.