The sputter-deposited fcc-MgO (001)/bcc-Co40Fe40B20 (001) spin-tunnel contact (STC) was succebfully prepared on n-Ge(001). We found that the interfacial modification by ultrathin (6 A) Mg insertion at the interface between n-Ge and MgO plays an important role in spin injection into Ge. The significantly amplified spin accumulation was observed in this STC as a result of the structural modification. The three-terminal Hanle signal of this STC was 2.7 times larger than that of the STC without Mg insertion. Our study confirms that a sputtering technique is indeed practical and useful to modify interfacial structures for the efficient injection of spins into semiconductors.
Bibliographical noteFunding Information:
The authors thank Dr. Yun Chang Park (NNFC) for help of XHRTEM observations and Ube Material Industries Ltd. in Japan for their support in providing single-crystal like MgO targets. This research was supported in part by the Future Semiconductor Device Technology Development Program (10044723) funded by Ministry of Trade, Industry and Energy and Korea Semiconductor Research Consortium, by Creative Materials Discovery Program (2015M3D1A1070465) and Grant (2014R1A2A1A11050290) through the National Research Foundation of Korea funded by the Ministry of Science, ICT and Future Planning of the Korea government, and by the Agency for Defense Development of the Republic of Korea.
© 2016 The Japan Society of Applied Physics.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)