Epitaxial Atomic Layer Deposition of Sn-Doped Indium Oxide

Coherently strained, epitaxial Sn-doped
In2O3 (ITO) thin films were fabricated at temperatures
as low as 250 °C
using atomic layer deposition (ALD) on (001)-, (011)-, and (111)-oriented
single-crystal Y-stabilized ZrO2 (YSZ) substrates. Resultant
films possess cube-on-cube epitaxial relationships with the underlying
YSZ substrates and are smooth, highly conductive, and optically transparent.
This epitaxial ALD approach is favorable compared to many conventional
growth techniques as it is a large-scale synthesis method that does
not necessitate the use of high temperatures or ultrahigh vacuum.
These films may prove valuable as a conductive growth template in
areas where high-quality crystalline thin film substrates are important,
such as solar energy materials, light-emitting diodes, or wide bandgap
semiconductors. Furthermore, we discuss the applicability of this
ALD system as an excellent model system for the study of ALD surface
chemistry, nucleation, and film growth.