Structure and magnetic properties of Fe-N thin films grown by ecr deposition

摘要

The growth of Fe_xN_y thin films on GaAs, In_(0.2)Ga_(0.8)As, and SiO_2/Si substrates using an ultra high-vacuum (UHV) deposition chamber equipped with electron cyclotron resonance (ECR) microwave plasma source is presented. The structural properties of the deposited films have been measured using various techniques as x-ray diffraction (XRD), Auger electron spectroscopy (AES), and transmission electron microscopy (TEM). The results of XRD measurements show that the films consist of a combination of alpha -Fe, alpha '-Fe, gamma -Fe_4N, and alpha "-Fe_(16)N_2 phases. The depth profiles, calculated from the Auger peak intensities, show a uniform nitrogen concentration through the films. The TEM reveals a columnar structure of these films. The properties of the different Fe-N layers have been exploited in the fabrication of Fe(N) / Fe_xN_y / Fe trilayer structures, where Fe(N) means a slightly nitrogen doped Fe film. The magneto-transport properties of this trilayer structure grown on In_(0.2)Ga_(0.8)As substrates are presented.