Ferromagnetic Germanide in Ge Nanowire Transistors for Spintronics Application
详细信息 查看全文
- 作者：Jianshi Tang ; Chiu-Yen Wang ; Min-Hsiu Hung ; Xiaowei Jiang ; Li-Te Chang ; Liang He ; Pei-Hsuan Liu ; Hong-Jie Yang ; Hsing-Yu Tuan ; Lih-Juann Chen ; Kang L. Wang
- 刊名：ACS Nano
- 出版年：2012
- 出版时间：June 26, 2012
- 年：2012
- 卷：6
- 期：6
- 页码：5710-5717
- 全文大小：544K
- 年卷期：v.6,no.6(June 26, 2012)
- ISSN：1936-086X
文摘
To explore spintronics applications for Ge nanowire heterostructures formed by thermal annealing, it is critical to develop a ferromagnetic germanide with high Curie temperature and take advantage of the high-quality interface between Ge and the formed ferromagnetic germanide. In this work, we report, for the first time, the formation and characterization of Mn5Ge3/Ge/Mn5Ge3 nanowire transistors, in which the room-temperature ferromagnetic germanide was found through the solid-state reaction between a single-crystalline Ge nanowire and Mn contact pads upon thermal annealing. The atomically clean interface between Mn5Ge3 and Ge with a relatively small lattice mismatch of 10.6% indicates that Mn5Ge3 is a high-quality ferromagnetic contact to Ge. Temperature-dependent I鈥?i>V measurements on the Mn5Ge3/Ge/Mn5Ge3 nanowire heterostructure reveal a Schottky barrier height of 0.25 eV for the Mn5Ge3 contact to p-type Ge. The Ge nanowire field-effect transistors built on the Mn5Ge3/Ge/Mn5Ge3 heterostructure exhibit a high-performance p-type behavior with a current on/off ratio close to 105, and a hole mobility of 150鈥?00 cm2/(V s). Temperature-dependent resistance of a fully germanided Mn5Ge3 nanowire shows a clear transition behavior near the Curie temperature of Mn5Ge3 at about 300 K. Our findings of the high-quality room-temperature ferromagnetic Mn5Ge3 contact represent a promising step toward electrical spin injection into Ge nanowires and thus the realization of high-efficiency spintronic devices for room-temperature applications.