Studying the Crystallization of ALD-Deposited Doped Nb₂O₅ into NbO₂ for Next Generation Electronics Applications

Phase change materials have a variety of applications across many disciplines. They can be used in homes to produce more energy-efficient refrigerators and freezers, or in clothes to help regulate body temperature in varying climates. NbO₂ is one such material, and can be used in a variety of electronic applications. In this project, we studied the conversion of amorphous Nb₂O₅ thin-films doped with either Al₂O₃ or ZnO (supplied by our collaborators at the Naval Research Laboratory) to crystalline NbO₂. Previous studies show Nb₂O₅ can be converted into NbO₂ by annealing to temperatures around 800 C. Systematic anneals in a tube furnace showed how the dopants affect the conversion of Nb₂O₅ into NbO₂. Our results indicate that samples of Nb₂O₅ doped with Al₂O₃ convert much slower than pure Nb₂O₅, and those with ZnO appear to convert faster.