2. Buffer layer architecture
Textured MgO thin film growth
- Inclined Substrate Deposition (ISD) method was used for the growth of MgO oriented films;
- Electron beam evaporation conditions for MgO:
- base pressure: 2 × 10^(-7) Torr
- α = 45°
- deposition rate: 50 nm/s
- film thickness: 1 micron
- RMS roughness of the as-obtained thin film was 13.9 nm, and peak-to-valley distance was 113.3 nm
- Schematic diagram of the ISD method and AFM images of the as-obtained films are shown below
LaMnO3 buffer layer deposition
- LaMnO3 thin film was deposited using the Chemical Solution Deposition (CSD) method
- Precursor solution:
- lanthanum and manganese acetylacetonates (La(CH3COCHCOCH3)3· xH2O and Mn(CH3COCHCOCH3)3· xH2O) were mixed in the appropriate stoichiometric ratio in an excess of propionic acid
- final solution concentration was 0.8 M
- Precursor film was deposited on the MgO-ISD layer by spin coating
- Thermal treatment:
- 600 °C, heating rate, 5 °C/min in air - decomposition of the precursor gel
- 900 °C in air - crystallization
- Exceptionally low RMS roughness of 2.3 nm, with a peak-to-valley value of 40 nm
- 5 µm × 5 µm and 1 µm × 1 µm AFM images of the LMO thin film deposited on MgO buffer layer are presented below