Tosoh SMD has introduced new transparent conducting oxide (TCO) sputtering targets that achieve higher solar cell efficiency than standard targets. Tosoh's new TCO targets are available in planar and rotary configurations and are composed of either traditional indium tin oxide (ITO) or aluminum zinc oxide (AZO). However, they are doped with performance-enhancing additives, such that thin films deposited from these targets have improved optical properties, in particular increased transparency. As a result, the conversion efficiency of solar cells in which such thin films are applied increases more than one point compared with solar cells using thin films from conventional TCO targets. According to the company the new targets will contribute to achieving 18% energy conversion efficiency with a focus on low-cost and large-scale production.
TCO targets for leading-edge thin-film solar applications require a stringent combination of optical, electrical, and mechanical properties and the durability to meet manufacturers' lifetime expectations.
Tosoh's new ITO and AZO TCO targets produce films that are highly transparent, especially in the visible to infrared range, and that feature high thermal stability, including under humid conditions. The targets enable the deposition of textured surfaces that feature enhanced light-trapping capability. Compared with thin-films from conventional TCO targets, a single-junction thin film deposited by a Tosoh AZO TCO target in a silicon solar cell shows a one-point gain in conversion efficiency. Thin-films achieve a similar gain in a copper indium gallium selenide (CIGS)-based solar cell.
New products are available as Transparent Conducting Oxide rotary aluminum and zinc oxide (AZO) sputtering targets. Tosoh SMD, is compliant with ISO/TS-16949:2000 and is currently registered to ISO-9001:2000 and ISO-14001:2004.
Tosoh is engaging customers in North America and Europe for the beta testing and high-volume production of its enhanced TCO targets.