RF-sputtered Cd2SnO4 for flexible glass CdTe solar cells

Cd
₂
SnO
₄
(CTO) is an interesting transparent conducting oxide (TCO) material for CdTe photovoltaic devices, but high quality CTO typically requires a post-deposition high temperature annealing step to promote crystallization. Wu [1] showed that deposition of the CdTe absorber layer by closed space sublimation (CSS) could provide sufficient thermal energy to achieve the desired optical and electrical properties for the CTO layer in finished devices. Here, we examine the optical and electrical properties of the CTO layer in a study of CdTe devices prepared by the CSS technique. The goal of this work is to understand the critical factors effecting the preparation of CTO layers to enable the preparation of CdTe devices on flexible glass. CdTe devices were completed on a number of substrates, with a best device efficiency of 14.4% on a Corning® Willow® Glass substrate.