The absorption edge increases as the amount of fluorine is raised. The optical energy gap E g is mainly determined by CF bond in the films, which results in the change of the density of states in band tail of the valence band.

• 薄膜中氟的引入对吸收边和光学带隙产生较大的影响 ,吸收边随氟含量的提高而增大 ,光学带隙则主要取决于CF键的含量 ,是由于强电负性F的引入改变了价带带尾附近带隙中态密度的结果所至