AZO electrode with high transmittance in IR range for CIS thin film solar cells

초록

We studied Al-doped ZnO (AZO) thin film as a transparent conducting layer for wide range solar spectrum. Deposition temperture effects on optical, structural and electrical properties of thin AZO film were investigated. AZO films were deposited on glass substrate by RF magnetron co-sputtering system using a single target of 2 wt. % Al2O3 doped ZnO under different temperature conditions. . The grown AZO films under low deposition temperatures from 100 °C to 300 °C show relatively low resistivity properties, while the samples deposited at higher temperature or room temperature are with relatively higher resistivity values. From the structural observations, very smooth surface morphologies from all deposited AZO films about 1 nm are observed Overall optical transmittance increases from 81% to 95% as the substrate temperature increases. Under optimized condition, AZO films exhibited an excellent 43.7  10-3 Ω-1 figure of merit with resistivity of 3.4 10-4 Ω•cm and transmittance of 94 %.