Improving the long-term stability of new-generation perovskite-based TCOs using binary and ternary oxides capping layers†

We report the impact of capping layers on vanadate based transparent conductive oxides (TCOs) to prolong the thermal stability with a minimal loss of electrical conductivity during heat treatment in ambient environment. In the present study, various capping layers (amorphous Al₂O₃, LaAlO₃ (LAO), TiO₂ grown at base pressure and TiO₂ deposited under oxygen partial pressure) are grown in situ on polycrystalline perovskite SrVO₃ (SVO) thin films using Pulsed Laser Deposition (PLD). The results show that amorphous LaAlO₃ is the most promising capping layer among the oxide layers, to preserve both electrical and optical properties of perovskite SVO films from natural as well as artificial aging. Our present approach for a capping layer on SVO may address the long-term stability issues of correlated TCOs and would open an opportunity for the future oxide electronics applications.