Thermal instability of the half-metallic CrO2 film epitaxially grown on TiO2

We have investigated the thermal instability of the half-metallic CrO2 films epitaxially grown on the (002) and (200) TiO2 (rutile) substrates by chemical vapor deposition. The temperature-dependent x-ray diffraction measurement directly revealed that the epitaxial CrO2 film on TiO2 was decomposed above 250 °C and recrystallized to the heteroepitaxial Cr2 O3 film above 300-350 °C. These results will be a guide for a thermal instability parameter in a development of spintronic devices using the half-metallic CrO2 film.