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Abstract: In this study, the optical properties and morphologies of Al-doped ZnO (AZO) films textured by the chemical wet-etching method with three different acid species are investigated. An initial AZO film is sputtered on a glass substrate by rf magnetron sputtering. The film surface was then textured by wet-etching using diluted HCl, HNO3 or H3PO4. The average transmittance of all the post-treated ZnO:Al films remains around 75–80% as measured by a UV–vis analyzer. A haze ratio calculation shows that the light scattering properties can be significantly controlled by varying the etchant species, acid concentration, and etching time. Atomic force microscopy (AFM) was used to find the average roughness of the textured AZO films. In this study, the HNO3 etchant gives the highest haze ratio of 49.2% at a wavelength of 550nm. The textured ZnO:Al films with an electrical resistivity of 5.47×10−4 Ω-cm, carrier concentrations of 3.98×1020 cm−3 and mobility of 28.7cm2 V−1 s−1, can be obtained when etched in diluted HNO3 for 60s. It is found that the chemical wet-etched AZO glass substrate appears to be helpful in enhancing the short circuit current (J sc) when applied on silicon thin film solar cells. [Copyright &y& Elsevier]

In this paper, Al-doped ZnO (AZO) films are deposited on glasses substrate by RF magnetron sputtering. The optical, electrical and morphological properties of AZO films textured by wet-etching with different etchants, H 3 PO 4 , HCl, and HNO 3 are studied. It is found that the textured structure could enhance the light scattering and light trapping ability of amorphous silicon solar cells. The textured AZO film etched with HNO 3 exhibits optimized optical properties (T% ≧ 80% over entire wavelength, haze ratio > 40% at 550 nm wavelength) and excellent electrical properties (ρ = 5.86 × 10 −4 Ωcm). Scanning electron microscopy and Atomic force microscopy are used to observe surface morphology and average roughness of each textured AZO films. Finally, the textured AZO films etched by H 3 PO 4 , HCl and HNO 3 were applied to front electrode layer for p–i–n amorphous silicon solar cells. The highest conversion efficiency of amorphous silicon solar cell fabricated on HNO 3 -etched AZO film was 7.08% with open-circuit voltage, short-circuit current density and fill factor of 895 mV, 14.92 mA/cm 2 and 0.56, respectively. It shows a significantly enhancement in the short-circuit current density and conversion efficiency by 16.2% and 20.2%, respectively, compared with the solar cell fabricated on as-grown AZO film. [ABSTRACT FROM AUTHOR]