Enhanced electrical properties of amorphous In-Sn-Zn oxides through heterostructuring with Bi 2 Se 3 topological insulators

Amorphous indium tin zinc oxide (a-ITZO)/Bi 2 Se 3 nanoplatelets (NPs) were fabricated using a two-step procedure. First, Bi 2 Se 3 NPs were synthesized through thermal chemical vapor deposition at 600 °C on a glass substrate, and then a-ITZO was deposited on the surface of the Bi 2 Se 3 NPs via magnetron sputtering at room-temperature. The crystal structures of the a-ITZO/Bi 2 Se 3 NPs were determined via X-ray diffraction spectroscopy and high-resolution transmission electron microscopy. The elemental vibration modes and binding energies were measured using Raman spectroscopy and X-ray photoelectron spectroscopy. The morphologies were examined using field-emission scanning electron microscopy. The electrical properties of the a-ITZO/Bi 2 Se 3 NPs were evaluated using Hall effect measurements. The bulk carrier concentration of a-ITZO was not affected by the heterostructure with Bi 2 Se 3 . In the case of the Bi 2 Se 3 heterostructure, the carrier mobility and conductivity of a-ITZO were increased by 263.6% and 281.4%, respectively, whereas the resistivity of a-ITZO was reduced by 73.57%. This indicates that Bi 2 Se 3 significantly improves the electrical properties of a-ITZO through its heterostructure, expanding its potential applications in electronic and thermoelectric devices.