Investigation on the Texture Effect of RF Magnetron-Sputtered ZnO:Al Thin Films Etched by Using an ICP Etching Method for Heterojunction Si Solar Cell Applications

The effect of the etching gas ratio (Cl2/Ar) and the RF chuck power for dry etching of deposited aluminum-doped zinc oxide (AZO) films was investigated. The initially smooth films showed optical transparencies (T ≥ 80 %) and electrical properties (ρ = 1.14 × 10-3 Ωcm). The etch rate increased gradually with higher RF chuck power and Cl2 gas ratio, reaching a value of ~1450 Å/min. The surface morphology, electrical properties and diffuse reflectance were examined in the etched samples. Heterojunction solar cells with a AZO/p-a-SiC:H/c-Si/Al structure simulated on a textured AZO film show the higher short-circuit current (15.8 mA/㎠) and a higher quantum efficiency (75 %) in the wavelength range of 400 ~ 1100 nm, demonstrating effective light trapping. These results show the potential of a textured layer etched by using ICP etching for solar cell applications. KCI Citation Count: 6