Doping-Free Intrinsic Amorphous Silicon Thin-Film Solar Cell Having a Simple Structure of ${\rm Glass}/{\rm SnO}_{2}/{\rm MoO}_{3}/{\rm i}\hbox{-}{\rm a}\hbox{-}{\rm Si}/{\rm LiF}/{\rm Al}$

We fabricated doping-free intrinsic amorphous silicon (i-a-Si) thin-film solar cells having a structure of glass/SnO
₂
/MoO
₃
/i-a-Si/LiF/Al. The short-circuit current density of the cell markedly increased while the open-circuit voltage and fill factor were low due to a lower work-function of the MoO
₃
than that of a conventional amorphous silicon carbide film. To solve these drawbacks, we UV-treated on the MoO
₃
layer, obtaining a greatly enhanced conversion efficiency of 6.42%.