Effects of Na precursor layer deposited on Mo substrate about (In,Ga)_2Se_3 and CIGS layers

摘要

Na external doping using Na_2S precursors on Mo/Corning glass substrate is one of the simplest doping methods. But the method affects both surface morphology and preferred orientation of (In,Ga)_2Se_3 and CIGS films, especially when the thickness was increased. The textures of CIGS films prepared with 3-stage process appear to be inherited from the textures of the (In,Ga)_2Se_3 films deposited during the first stage, it can be assumed that the growth of (In,Ga)_2Se_3 films were modified with Na_2S precursors. As the thickness of Na precursor was increased, surface morphology of (In,Ga)2Se3 films was more smooth than that of the films which had thin Na precursor. And CIGS thin films made by these (In,Ga)_2Se_3 films showed that (112) orientation was stronger than (220/204) orientation. And also it was investigated there is a close relation about the morphology and the roughness between (In,Ga)_2S_e3 and CIGS films by AFM.