SCALING-UP OF CIS TECHNOLOGY FOR THIN-FILM SOLAR MODULES

The compound semiconductor Cu(Ga,In)Se-2 (CIGS) and related compounds have demonstrated their high potential for high-efficiency thin-film s olar cells up to levels approaching 18%. The Center for Solar Energy a nd Hydrogen Research (ZSW) and the University of Stuttgart (IPE) ave w orking together on CIS upscaling, On the module basis, ZSW is collabor ating with Phototronics Solartechnik GmbH/Putzbrunn as a manufacturer for a-Si modules supporting module technology. With the aim of develop ing high-volume fabrication technologies, all the laboratory depositio n techniques suitable for highest device performance are applied now a lso on the module level to avoid physical and chemical effects that co uld limit device performance to a low level, All film deposition techn iques are developed for high-vacuum in-line fabrication on a large are a, except for the buffer layer of CdS, and monolithic integration is r ealized by patterning steps. A key issue for the development of module s is upscaling of the CIGS absorber deposition, films of CIGS are prep ared by simultaneous thermal evaporation of the elements. Modules are prepared on substrate areas of 7 x 7, 10 x 10 ... 30 x 30 cm(2), Actua l results of modules of these sizes are shown.