High temperature chemical vapor deposition apparatus

Embodiments for an apparatus and method for depositing one or more layers onto a substrate or a freestanding shape inside a reaction chamber operating at a temperature of at least 700° C. and 10 torr are provided. The apparatus is provided with means for defining a volume space in the reaction chamber for pre-reacting the reactant feeds forming at least a reaction precursor in a gaseous form, and a volume space for depositing a coating layer of uniform thickness on the substrate from the reacted precursor. In one embodiment, the means for defining the two different zones comprises a distribution medium separating the pre-reaction zone from the deposition zone, for uniform distribution of the reacted precursor on the substrate. In another embodiment, the means for defining the two different zones comprises a plurality of reactant feed jets or injectors, for creating a jet-interaction zone or pre-reactant zone separate from a deposition zone, for deposing the reacted precursor on the substrate.