Publication Date:
2015-09-25
Description:
In this letter, we present electrical and magnetic characteristics of HfO 2 -based metal-oxide-semiconductor capacitors (MOSCAPs), along with the effect of pseudomorphic Si as a passivating interlayer on GaAs(001) grown by molecular beam epitaxy. Ultrathin HfO 2 high- k gate dielectric films (3–15 nm) have been grown on Si/GaAs(001) structures through evaporation of a Hf/HfO 2 target in NO 2 gas. The lowest interface states density D it at Au/HfO 2 /Si/GaAs(001) MOS-structures were obtained in the range of ( 6 − 13 ) × 10 11 eV −1 cm −2 after annealing in the 400–500 °C temperature range as a result of HfO 2 crystallization and the Si layer preservation in non-oxidized state on GaAs. HfO 2 -based MOSCAPs demonstrated the ferromagnetic properties which were attributed to the presence of both cation and anion vacancies according to the first-principle calculations. Room-temperature ferromagnetism in HfO 2 films allowed us to propose a structure for the ferromagnetic MOS spin-detector.
Print ISSN:
0003-6951
Electronic ISSN:
1077-3118
Topics:
Physics
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