TY - JOUR
T1 - Study on absence of room-temperature ferromagnetism in the Mn-AlN films with various Mn concentrations
AU - Sato, Takanobu
AU - Endo, Yasushi
AU - Kawamura, Yoshio
AU - Kirino, Fumiyoshi
AU - Nakatani, Ryoichi
AU - Yamamoto, Masahiko
N1 - Funding Information:
This work was supported in part by an Exploratory Research and Encouragement of Young Scientists (B) from the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan. This work was also supported by Priority Assistance for the Formation of Worldwide Renowned Centers of Research—The Global COE Program (Project: Center of Excellence for Advanced Structural and Functional Materials Design) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan. This work was also supported in part by Strategic Information and Communications R&D Promotion Programme (SCOPE) from the Ministry of Internal Affairs and Communications (MIC). The authors would like to thank Y. Takatsuru, K. Yamamoto, and S. Sato of Rigaku Corporation for performing the grazing-incidence X-ray diffraction analysis.
PY - 2008/11
Y1 - 2008/11
N2 - We have investigated the magnetic behavior and structure of polycrystalline Mn-AlN (Al1-xMnxN) films with various Mn concentrations (x = 0.05-0.24) fabricated by reactive direct current (dc) magnetron sputtering. The magnetic behavior of these films depends on the Mn concentration x. The films with x = 0.05-0.10 show a paramagnetic behavior at 10-300 K. The film with x = 0.17 shows remanent magnetization and coercivity only at 10 K, while that with x = 0.24 shows an unknown magnetic behavior. Only würtzite-type AlN phase is observed for x below 0.10. The coexistence of a würtzite-type AlN phase and a secondary phase such as Al-Mn alloy, Mn-nitride, or Al-Mn-N ternary compound is observed for x = 0.17. The coexistence of a würtzite-type AlN phase and a ThH2-type Mn3N2 phase is observed for x = 0.24. From these results, it is concluded that the Al1- x!MnxN films do not exhibit room-temperature (RT) ferromagnetism for all x. Moreover, it is likely that the ferromagnetic behavior observed at 10 K for x = 0.17 is caused by the secondary phase.
AB - We have investigated the magnetic behavior and structure of polycrystalline Mn-AlN (Al1-xMnxN) films with various Mn concentrations (x = 0.05-0.24) fabricated by reactive direct current (dc) magnetron sputtering. The magnetic behavior of these films depends on the Mn concentration x. The films with x = 0.05-0.10 show a paramagnetic behavior at 10-300 K. The film with x = 0.17 shows remanent magnetization and coercivity only at 10 K, while that with x = 0.24 shows an unknown magnetic behavior. Only würtzite-type AlN phase is observed for x below 0.10. The coexistence of a würtzite-type AlN phase and a secondary phase such as Al-Mn alloy, Mn-nitride, or Al-Mn-N ternary compound is observed for x = 0.17. The coexistence of a würtzite-type AlN phase and a ThH2-type Mn3N2 phase is observed for x = 0.24. From these results, it is concluded that the Al1- x!MnxN films do not exhibit room-temperature (RT) ferromagnetism for all x. Moreover, it is likely that the ferromagnetic behavior observed at 10 K for x = 0.17 is caused by the secondary phase.
KW - Magnetic semiconductors
KW - Mn-AlN films
KW - Paramagnetic behavior
KW - Room-temperature (RT) ferromagnetism
UR - http://www.scopus.com/inward/record.url?scp=85130087843&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85130087843&partnerID=8YFLogxK
U2 - 10.1109/TMAG.2008.2002366
DO - 10.1109/TMAG.2008.2002366
M3 - Article
AN - SCOPUS:77955120333
SN - 0018-9464
VL - 44
SP - 2688
EP - 2691
JO - IEEE Transactions on Magnetics
JF - IEEE Transactions on Magnetics
IS - 11 PART 2
ER -