MgCl2 for MgAl2O4 films by open-tube VPE
Magnesium chloride MgCl2 was applied as precursor for the preparation of epitaxial MgAl2O4 films on Si(100) substrates by open-tube vapor phase epitaxy (VPE) at deposition temperature ~1000 °C using precursor system MgCl2–Al–HCl–CO2–H2The grown films were used for preparation of Si/MgAl2O4/Si heterostructures. Silicon film quality improved using thinner spinel films with smoother surfaces in the range of ∼0.1 μm, in spite of the spinel crystal perfection becoming inferior with decreasing film thickness; these results were discussed in terms of the spinel surface roughness effect on Si nuclei coalescence. .[110, 111]
MgCl2 for MgAl2O4 films by CVD
MgAl2O4 films having (100) orientation were grown by CVD as buffer for PbTiO3 films on Si(100) substrates. Precursor systemMgCl2–Al–HCl–CO2–H2 was used, where Al was transported as AlCl3, formed in situ by reaction between Al and HCl, and MgCl2-AlCl3 and CO2-H2 mixtures were transported separately by N2 carrier gas to the reaction chamber, where epitaxial growth occurred. The following overall reaction occurred during deposition process: MgCl2 + 2 AlCl3 + 4 CO2 + 4 H2 -> MgAl2O4 + 4CO + 8HCl. Growth rate of MgAl2O4 films was 8nm/min and was controlled by the surface reaction with an activation energy 1.0 eV .[112, 113]
MgCl2 for Mg-doped LaCrO3 films by electrochemical CVD
MgCl2 was used as dopant precursor for the Mg-doped LaCrO3 films electrochemical vapor deposition ECVD (in combination with anhydrous CrCl3, LaCl3 and O2 as oxidant), at 1200-1300°C on porous Ca-stabilised zirconia (CSZ) substrates. Metal chlorides were produced in situ by corresponding metal chlorination with HCl. Mg content in the LaCrO3 was very low (<2%), despite excess of MgCl2 in the reactant stream. [889]