Physical and structural studies of chemical Vapor deposited lacunar neodymium manganite thin films

摘要

Lacunar Nd1-xMnO3-δ thin films were successfully deposited by a liquid source metal-organic MOCVD technique on (001) SrTiO3 (STO), LaAlO3 (LAO) and Si substrates. Optimal growth conditions are reported. TEM and X-ray diffraction characterisations reveal that the thin films grown on STO and LAO substrates are single crystalline layers epitaxially grown on the top of the substrates. The relationship between the crystallographic orientation of the films and those of the substrates were determined. Magnetic transition temperatures (Tc) of the as-grown STO films, deduced from Squid Magnetometer measurements, are compared to the corresponding bulk values (typically 100K). Our magnetic measurements also suggest a complicated magnetic behavior close to the one observed in bulk samples: magnetization curves obtained under different applied magnetic fields indicate a possible reverse of the magnetization sign at low temperatures.PACS: 73-43-Qt – / 75-50-Ee – Key words: CVD / thin film / X-ray diffraction / magnetic properties