Production of a ceramic oxide based coating conforming with the geometry of a substrate with raised designs, using a sol-gel technique with a precursor solution of the ceramic oxide

摘要

#CMT# #/CMT# Production of a ceramic oxide conformable coating on a substrate having raised designs comprises: (a) deposition of a sol-gel solution layer, as a precursor of the ceramic, on the substrate; (b) heat treatment of the layer to form the ceramic; (c) optional repetition of these steps; (d) the sol-gel solution is prepared by contacting metal molecular precursors of the ceramic in a diol solvent and possibly aliphatic monoalcohol, allowing the solution to rest to obtain an essentially constant viscosity and diluting the solution with a diol solvent. #CMT#USE : #/CMT# The invention is used for the production of a ceramic oxide coating conforming to the geometry of a substrate having relief patterns, in particular patterns at a micrometric scale. #CMT#ADVANTAGE : #/CMT# The invention using the sol-gel technique allows the production of coatings on complex surfaces of various sizes without the need for heavy equipment. It produces coatings with an homogeneous composition. Due to the use of a mixture of species at a molecular scale, it is possible to easily produce complex oxide coatings comprising, for example, three elements or more and to control the stoichiometry. The coatings obtained conform to the geometry of the substrate, presenting an essentially uniform thickness over the whole length of the deposit notably thanks to the stability of the sol-gel solution prior to deposition. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing illustrates a transverse section of a part of a substrate having some patterns in the form of slices provided with a coating illustrating the sizes necessary for the determination of the conformity factors. #CMT#CERAMICS AND GLASS : #/CMT# The ceramic oxide may be chosen from lead zircono-titanate (PZT), barium titanate, barium and strontium titanate (BST), lead, niobium and zinc titanate (PZNT), zinc and lead niobate (PZN), magnesium and lead niobate (PMN), lead titanate (PT), potassium and calcium niobate, bismuth and potassium titanate (BKT), bismuth and strontium titanate (SBT), potassium tantalite (KLT) and solid solutions of PMN and PT (claimed). The ceramic oxide may be chosen from silica (SiO 2), hafnium oxide (HfO 2), zirconium oxide (ZrO 2), alumina (Al 2O 3) and tantalum oxide (Ta 2O 5) (claimed). The metal or metalloid molecular precursor may be an inorganic metal or metalloid salt or a metal or metalloid organometallic compound (claimed).