Patent ID: 8336489

Claim:
A thermal evaporation apparatus for depositing a material on a substrate, the apparatus comprising: material storage means for receiving the material to be deposited, wherein at least the surfaces of the material storage means arranged to come into contact with vapour of the material to be deposited are constructed of a material selected from the group consisting of quartz, fused silica, ceramic, graphite and carbon-fibre-enforced-carbon (CFC); heating means for heating the material in the material storage means to generate a vapour; vapour outlet means arranged to receive in its interior said vapour, said vapour outlet means comprising: a vapour receiving pipe having vapour outlet passages, wherein at least the surfaces of the vapour receiving pipe arranged to come into contact with the vapour are constructed of a material selected from the group consisting of quartz, fused silica, ceramic, graphite and carbon-fibre-enforced-carbon (CFC), and emission reducing means arranged such that an external surface of the vapour outlet means directed to said substrate exhibits emissivity of 0.6 or less, wherein at least the surfaces of the emission reducing means arranged to come into contact with the vapour are constructed of a material selected from the group consisting of quartz, fused silica, ceramic, graphite and carbon-fibre-enforced-carbon (CFC), and wherein the apparatus further comprises pipe heating means arranged in the interior of said vapour outlet means, said pipe heating means being provided with an outer corrosion-resistant surface arranged to come into contact with the material vapour and being formed of a material selected from the group consisting of quartz, fused silica, ceramic, and graphite.