Service Communautaire d'Information sur la Recherche et le Développement - CORDIS

Fully reproducible low pressure metal organic chemical vapour deposition sources for metal oxides, including HTS, and for metal fluorides.

Alkaline and rare earth metal complexes fully suitable for use in low pressure metal organic chemical vapour deposition (LP-MOCVD) processes in all equipment, including those employing conventional, heated bubbler, sources. It is the only technology currently providing stable, reliable and reproducible mass transport and, hence, deposition rates from conventional equipment.

Alkaline earth metal complexes of form [M(RCOCHCOR)2L](R=perfluoroalkyl,L=polydentate O or N donor, typically polyether) can be:
handled in air;
evaporated completely without dissociation or decomposition at ambient pressures;
fully thermally stable liquids at temperature of use as MOCVD source.

Rare earth metal complexes of the form [M(RCOCHCOR)3L](R=But,L=4-alkylpyridine-N-oxide) offer the same advantages and are also fluorine free.

The complex [Ba(C3F7COCHCOC3F7)2.CH3O(CH2CH2O)4CH3] has been used in a fully in situ process to deposit 300 nm thick yttrium boron carbon oxygen (YBCO) film on 8 mm x 8 mm SrTiO3 with Tc=92.9 K, Jc=0.9 MA cm{-2} measured by ac susceptibility. Reproducibility is good, as are the prospects for large area deposition.

The complexes will additionally be useful in deposition of other electronic grade ceramics of commercial interest. This includes ferroelectric (BaTiO3), buffer layer or electrolyte (YSZ) and glasses doped with rare earth metals. The alkaline earth metal complexes may also be used to deposit fluorides as optical coatings and components for glasses.


Barbara RICHARDS, (Research Chemist)
Tél.: +44-51-3553611
Fax: +44-51-3566112