Spectrally selective PbS films produced by ion beam sputtering

Ion beam sputtering was used to deposit thin films of PbS for use as solar selective absorbers. Comparative tests showed that ion-beam-deposited films were harder than thermally produced films, had a smaller mean crystallite size of about 500 A and had a surface relatively free of any texture. The addition of an antireflecting ZrO2 layer further improved the hardness and increased the solar absorptance from 66% to 80%. (Auth.)