Patent ID: 6171458
Filing Date: 2001-01-09
Classification: C23C,F24S,Y02E,Y02P

Abstract:
A process for manufacturing on a movable receiving material a spectral selective absorbing layer for solar collectors, the spectral selective absorbing layer having a high solar absorption ability and a low thermal emittance, the process comprising:atomizing metal in a coating zone present in a chamber having a sputtering atmosphere, the atmosphere containing oxygen and at least one gas supporting the sputtering, whereby the atomized metal forms the cathode and the movable receiving material forms the anode, the anode and the cathode providing a difference in electrical potential and thereby a plasma gas, anddepositing the atomized metal by sputtering on the movable receiving material, characterized by:providing an amount of oxygen in the coating zone of between about 1 and 50 cm.sup.3 /min, kW to deposit a layer of the metal onto the movable receiving material, the amount of oxygen in the coating zone being selected to partly oxidize the deposited metal to provide a mixture of the metal and metal oxide wherein between about 40 and 80% of the metal is embedded into the metal oxide closest to the movable receiving material; andincreasing the amount of oxygen at the end of the coating zone to decrease the amount of the metal embedded into the metal oxide to about zero at the surface of the layer,the metal atomized in the coating zone being selected from the group consisting of nickel, chromium, cobalt and molybdenum.