International Journal of Photoenergy (Jan 2015)
Effects of Sulfurization Pressure on the Conversion Efficiency of Cosputtered Cu2ZnSnS4 Thin Film Solar Cells
Abstract
We report herein Cu2ZnSnS4 (CZTS) thin film solar cells with 6.75% conversion efficiency, without an antireflection coating. The CZTS precursors have been prepared by cosputtering using three different targets on Mo-coated substrates: copper (Cu), tin sulfide (SnS), and zinc (Zn). The postsulfurization was carried out at different pressures in a H2S/N2 environment at 550°C for one hour. A comparative study on the performances of solar cells with CZTS absorber layers prepared at different sulfurization pressures was carried out. The device efficiency of 1.67% using CZTS absorber and low pressure sulfurization is drastically improved, to an efficiency of 6.75% with atmospheric pressure sulfurization.