Solar cell fabrication using two-step textured quasi-single crystalline silicon by alkaline and RIE texturing processes

Abstract

After alkaline chemical texturing process, SF6/O2 reactive ion etching (RIE) was used for maskless textured Si surface independently from crystal orientation. Additional RIE texturing on alkaline textured Si surface increased the light receiving areas and decreased the surface reflectance by random pyramidal structures with a width of hundreds of nanometers. The weighted average reflectance (WAR) of the textured Si surface by two-step texturing processes was achieved as low as 9.6% in the 300–1200 nm wavelength range. Compared to the alkaline texturing, the alkaline and RIE texturing of front Si surfaces decreased the WAR by 6%. By means of two-step texturing processes for quasi-single crystalline silicon (QSC-Si) surfaces, performance parameters of the solar cell such as conversion efficiency, short circuit current density (Jsc), open circuit voltage (Voc) and fill factor (FF) were examined in 18.2%, 36.6 mA/cm2, 624 mV and 79.7%, respectively.