A germanate transparent conductive oxide

作者：Mizoguchi Hiroshi; Kamiya Toshio; Matsuishi Satoru; Hosono Hideo^*

来源：Nature Communications, 2011, 2(1): 470.

DOI：10.1038/ncomms1484

Wide bandgap conductors such as In2O3 and ZnO are used as transparent conducting oxides (TCOs). To date, TCOs are realized using post transition metal cations with largely spread s-orbitals such as In3+, Sn4+, Zn2+ and Cd2+. On the other hand, no good electronic conductor has been realized in oxides of Al, Si and Ge. Here we report the conversion of an oxide of Ge into a good electronic conductor by employing the concept of superdegeneracy. We find that cubic SrGeO3, synthesized under high pressure, displays a direct bandgap of 3.5 eV, a carrier mobility of 12 cm(2)(Vs)(-1), and conductivities of 3 S Scm(-1) (DC) and 400 S Scm(-1) (optical conductivity). This is the first Ge-based electronic conductive oxide, and expands the family of TCOs from ionic oxides to covalent oxides.

• 出版日期2011-9