Onset of hard magnetic MnGa thin film on glass substrate

In this study, magnetic properties and microstructure of L1(0) MnGa thin films deposited at different substrate temperatures (T-s) were carried out in order to determine the onset of the hard magnetic MnGa phase onto glass substrate. The thickness of MnGa thin film was kept at 200 nm while the T-s was varied from room temperature (RT) to 600 degrees C. When the T-s was below 300 degrees C, only Mn phases with small grain size were observable. However, the further increase in T-s to 325 degrees C led to the appearance of L1(0) (111) peak indicating the presence of the hard magnetic phase in the film on the glass substrate. Also, the continuous rise in T-s enhanced the magnetic properties such as saturation magnetization (M-s) and coercivity (H-c). The crystal size of L1(0) MnGa phase and surface roughness of the film were also increased with the increase of T-s. The selected area diffraction pattern (SADP) of Transition Electron Microscopy (TEM) effectively identified that the coexistence of pure Mn and Al MnGa phases were present at T-s < 300 degrees C and that the Llo MnGa started to appear at T s = 325 degrees C while the completion of Llo MnGa phase was seen at T-s > 400 degrees C. The High-Resolution TEM (HRTEM) images revealed the lattice and amorphous regions present in the MnGa thin film at T-s = 325 degrees C. Nevertheless, an increase of T-s to 600 degrees C presented a wide range of L1(0) (111) lattice signifying the thin film is still in MnGa phase. The onset of hard magnetic L1(0) MnGa phase is found out to be at 325 degrees C.

Automated summary

This study investigated the magnetic properties and microstructure of L1(0) MnGa thin films deposited at different substrate temperatures. The onset of the hard magnetic phase was found to be at 325 degrees C, with an enhancement in properties like saturation magnetization and coercivity as the substrate temperature increased. Results also showed an increase in crystal size and surface roughness with increasing substrate temperature.