Patent ID: 7413767

Claim:
A method for producing optical functional coatings comprising niobium, tantalum, titanium or aluminum by supplying a precursor gas of low vapor pressure in a CVD coating system, comprising the steps of: maintaining a precursor selected from the group consisting of Nb, Ta, Ti, and Al compounds having a vapor pressure within a first supply container at a first temperature T 1 and a first pressure p 1 ; supplying precursor vapor of the precursor from the first supply container to an intermediate storage device through a first gas line which fluidly communicates the first supply container and the intermediate storage device; supplying a carrier gas or reaction gas to the first gas line such that a mixture of the precursor with the carrier gas or the reaction gas is provided: maintaining the mixture in the intermediate storage device at a constant second pressure p 2 lower than the first pressure p 1 and at a second temperature T 2 lower than the first temperature T 1 ; and supplying the mixture from the intermediate storage device through a second gas line.