Papers by Author: Hyun Jung Kim

Abstract: We report on the effect of the oxygen partial pressure ratio in the sputtering gas mixture on the electrical and magnetic properties of cubic spinel ZnCo₂O₄ thin films grown by reactive magnetron sputtering. The conduction type and carrier concentration in ZnCo₂O₄ films were found to be dependent on the oxygen partial pressure ratio. The maximum electron and hole concentration at 300 K were estimated to be as high as 1.37 × 1020 cm^-3 and 2.81 × 10²⁰ cm^-3, respectively. While an antiferromagnetic coupling was found for n-type ZnCo₂O₄, a ferromagnetic interaction was observable in p-type ZnCo₂O₄, indicating hole-induced ferromagnetic transition in spinel ZnCo₂O₄.