Preparation of High Efficient Solar Absorbers by Low-Pressure Sputtering
Abstract
Multilayer solar power absorber was implemented by a novel DC sputtering method for metal deposition at low pressures. A Mo-Zn-Mo multilayer system was deposited in argon atmosphere using pressure of 0.1-1 mTorr and sputtering voltage of 1,500-2,000 V. A lower Mo sub-layer represents a high reflective film, providing high adhesion with substrate, glass or metal. A thick Zn interlayer, deposited by flash sputtering, creates a high porous absorbing layer. An upper Mo coating protects the system and stabilizes it. This black multilayer system uses as an absorbing coating and may be applied for solar absorbers fabrication. High deposition rate and reproducible process due to the sheet plasma sputtering technology was obtained. Preliminary measurements showed high thermal stability of the novel multilayer solar absorbers in vacuum conditions.