https://doi.org/10.1051/epjap/2010100015
Synthesis, microstructure, and properties of Ge1-xCox diluted magnetic semiconductor films
1
College of Materials Science and Technology, Qingdao University of Science
and Technology, 53 Zheng-zhou Road, Qingdao, 266042, P.R. China
2
National Laboratory for Infrared Physics, Shanghai Institute of Technical
Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, P.R. China
3
Key Laboratory of Polar Materials and Devices, Ministry of Education, East
China Normal University, 500 Dong-Chuan Road, Shanghai, 200241, P.R. China
Corresponding author: jingchengbin0028@sina.com
Received:
11
January
2010
Revised:
10
June
2010
Accepted:
16
November
2010
Published online:
28
January
2011
Co-doped GeO2 ceramic films were prepared via a liquid phase co-deposition (LPCD) process. The oxide samples were transformed into Ge1-xCox films (x = 0.75, 3.2 and 11.5%) after annealing under hydrogen atmosphere. The crystallinity of Ge1-xCox film decreases with increasing Co content. The Ge1-xCox films are p-type (hole density 1020 ~ 1021 cm-3). The 3.2% film has higher electrical conductivity and hole density compared with the other two samples. The 0.75% film is superparamagnetic at 300 K while the 3.2% and 11.5% films exhibit blocked superparamagnetic behaviors. Hysteresis loops can be observed in the magnetization curves of the 3.2 and 11.5% samples. The observed ferromagnetisms are on only a local (a few nanometers) scale, which most likely arise from different size and chemical distribution in every sample.
© EDP Sciences, 2011
