STUDIES OF LPCVD AL-FE-O DEPOSITS BY XPS, EELS AND MOSSBAUER SPECTROSCOPIES

Al-Fe-O layers were deposited on silicon carbide or aluminium nitride substrates by low-pressure chemical vapour deposition (LPCVD). Alumini um trichloride, hydrogen and nitrous oxide gases have been used to gen erate crystallized alumina. Simultaneously, iron pentacarbonyl combine d with carbon dioxide has beer added to introduce iron in the alumina layers. The relation between the morphology and iron content has been studied by SEM, XPS, TEM, EELS and Mossbauer techniques. Iron concentr ation is studied throughout the thickness of the films. It is homogene ous around 1 at% Fe for the lowest Fe(CO)(5)/AlCl3 ratio and it is het erogeneous for higher Fe(CO)(5)/AlCl3 ratios. (C) 1998 Elsevier Scienc e S.A.