Abstract: A heterojunction photovoltaic device for the production of electrical energy in response to the incident light includes an optically transparent substrate, a front contact formed of an transparent conductive oxide for collecting light generated charge carriers, an n-type window layer formed of cadmium sulfide or zinc sulfide, a p-type absorber structure disposed on the window layer, thereby forming a rectification junction therebetween, and a back contact comprising at least one metal layer. The p-type absorber structure has a plurality of p-type absorber layers in contiguous contact. Each absorber layer contains cadmium as a principal constituent and has a different composition and a different band gap energy. The first absorber layer is in contiguous contact with the n-type window layer. The band gap energy progressively decreases from the first absorber layer to the last absorber layer in the p-type absorber structure.

Abstract: An apparatus for high-rate chemical vapor (CVD) deposition of semiconductor films comprises a reaction chamber for receiving therein a substrate and a film forming gas, a gas inlet for introducing the film forming gas into the reaction chamber, an incidence window in the reaction chamber for transmission of a laser sheet into the reaction chamber, a laser disposed outside the reaction chamber for generating the laser sheet and an antenna disposed outside the reaction chamber for generating a plasma therein. The film forming gas in the chamber is excited and decomposed by the laser sheet, which passes in parallel with the substrate along a plane spaced apart therefrom, and concurrent ionization effected by the antenna, thereby forming a dense semiconductor film on the substrate at high rate.

Abstract: A continuous deposition process and apparatus for depositing semiconductor layers containing cadmium, tellurium or sulfur as a principal constituent on transparent substrates to form photovoltaic devices as the substrates are continuously conveyed through the deposition apparatus is described. The film deposition process for a photovoltaic device having an n-type window layer and three p-type absorber layers in contiguous contact is carried out by a modular continuous deposition apparatus which has a plurality of processing stations connected in series for depositing successive layers of semiconductor films onto continuously conveying substrates. The fabrication starts by providing an optically transparent substrate coated with a transparent conductive oxide layer, onto which an n-type window layer formed of CdS or CdZnS is sputter deposited. After the window layer is deposited, a first absorber layer is deposited thereon by sputter deposition.