Fabrication of high open‐circuit voltage a‐Si_1–<i>x</i>O<i>_x</i>:H solar cells by using p‐a‐Si_1–<i>x</i>O<i>_x</i>:H as window layer

Abstract

Abstract We have deposited p‐type hydrogenated amorphous silicon oxide (p‐a‐Si 1‐x O x :H) by 13.56 MHz radio frequency plasma enhanced chemical vapor deposition (RF‐PECVD) using a gas mixture of silane (SiH 4 ), hydrogen (H 2 ), carbon dioxide (CO 2 ) and diborane (B 2 H 6 ). Optical and electrical characterization showed that high quality wide optical band‐gap ( E opt ) p‐a‐Si 1‐x O x :H films could be achieved by using low doping concentration and high H 2 dilution. We also fabricated a‐Si 1‐x O x :H single‐junction p‐i‐n solar cells by using p‐a‐Si 1‐x O x :H and intrinsic a‐Si 1‐x O x :H as window and absorber layer, respectively. These solar cells exhibited open circuit voltages of over 1.05 V and good short‐circuit currents as well as fill factors (© 2011 WILEY‐VCH Verlag GmbH &amp; Co. KGaA, Weinheim)