Realization of room-temperature ferromagnetism and of improved carrier mobility in Mn-doped ZnO film by oxygen deficiency, introduced by hydrogen and heat treatments

Abstract

Room-temperature ferromagnetism and improved carrier mobility in Mn-doped ZnO film was realized by oxygen deficiency. The RTFM in Mn-doped ZnO film was successfully obtained by using the hydrogen implantation technique, and their mobility was significantly enhanced after annealing compared to the as-grown sample. The oxygen-resonant Ruthford Backscattering (RBS) spectra were used to determine the oxygen content in the samples as well as Mn and Zn. The increment of the carrier concentration in compensated by the reduction of carrier mobility, which showed that the existence of singly ionized oxygen vacancies in the oxygen deficient sample is unlikely. Results indicated that the decrease of lattice parameter is caused due to the relaxation of implanted hydrogen by the annealing process. The hydrogen-implanted in Mn-doped ZnO film was considered to be effective for the spintronics device application, where a high mobility is required for the high-speed devices.