Inserted Layer of AZO Thin Film with High Work Function Between Transparent Conductive Oxide and <I>p</I>-Layer and Its Solar Cell Application

Abstract

We report aluminum doped zinc oxide (AZO) films with high work function as an insertion layer between transparent conducting oxides (TCO) and hydrogenated amorphous silicon carbide (a-SiC:H) layer to improve open circuit voltage (V(oc)) and fill factor (FF) for thin film solar cells. Amorphous silicon (a-Si:H) solar cells exhibit poor fill factors due to a Schottky barrier at the interface between a-SiC:H window and TCO. The interface engineering is carried out by inserting an AZO layer with high work function (4.95 eV at O2 = 2 sccm). As a result, V(oc) and FF improved significantly. FF as high as 63.35% is obtained.