Nano-scale texturing of borosilicate glasses using CF4-based plasma discharge for application in thin film solar cells

Random plasma treatment techniques were used as a texturing method to reduce the surface reflection of glass substrates in thin film solar cells. Various gas mixtures were used for the plasma discharge in an effort to examine the texturing mechanism. Using a plasma treatment comprising CF4/O2 and CF4/Ar with a gas flow ratio of 1 to 2, the surface reflectance could be decreased to 6.83% and 6.82%, respectively. The surface treatment was very effective with the use of a low RF power of 50 W and an optimal time of 5 min. It is considered that the optical characteristics of the glass substrate are highly correlated to its surface morphology which can be produced not only through nano-scale chemical reactions with radicals but also through ion flux bombardment.