Germanium‐doped Czochralski silicon: a novel material for solar cells

Abstract

AbstractThe effect of Ge codoping on the light induced degradation (LID) of B doped Czochralski‐silicon (CZ‐Si) was investigated. The rate of degradation under illumination is relatively suppressed in B and Ge codoped Czochralski‐silicon (CZ‐Si) compared to B‐doped CZ‐Si. The Oi concentrations measured by FTIR spectroscopy was decreased as the Ge concentration increased in the Si crystal. The formation of Ge‐VO complex in silicon lattice is considered as a possible reason for the variation in Oi. Moreover, the compressive strain field around the Ge‐VO complex may increase the barrier for O diffusion which limits the formation of fast diffusing O dimmers. As a consequence, the B‐O dimmer (O2i) related defects were relatively suppressed, which causes the suppression of LID effect in B and Ge codoped CZ‐Si. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)