We report on the growth of spinel ZnCo2O4 films using reactive magnetron sputtering and their electrical and magnetic properties, with particular emphasis on the relation of Curie–Weiss temperature (TCW) and conduction type. The conduction type and carrier concentration in these films were found to be dependent on the oxygen partial pressure ratio in the sputtering gas mixture. The highest electron and hole concentration at 300 K were 1.37×1020 and 2.81×1020 cm−3, respectively. A ferromagnetic coupling (TCW>0) was observable in p-type ZnCo2O4, whereas an antiferromagnetic interaction (TCW<0) was found for n-type and insulating ZnCo2O4, revealing hole-induced ferromagnetic transition in ZnCo2O4.

We report the synthesis of spinel oxide ZnCo 2 O 4 thin films and the effects of the oxygen partial pressure in the sputtering gas mixture on their electrical and magnetic properties. The conduction type and carrier concentration were found to be dependent on the oxygen partial pressure ratio: n-type and p-type for the oxygen partial pressure ratio below ∼70% and above ∼85%, respectively. A ferromagnetic coupling was observable in p-type ZnCo 2 O 4 , whereas an antiferromagnetic interaction was found for insulating and n-type ZnCo 2 O 4 film, revealing hole-mediated ferromagnetic transition in ZnCo 2 O 4 . Arrott plot analysis of magnetization data at 5 K also indicated non-zero spontaneous magnetization for p-type ZnCo 2 O 4 .

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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.