Superior texture-controlled ZnO thin film using electrochemical deposition

• Developed a low cost electrochemical deposition process for high quality ZnO film.
• The crystal orientation and surface texture are adjusted via a chemical additive.
• Achieved superior light trapping using the optimized textured ZnO films.
• Attained high quantum efficiency for solar cells.

Superior texture-controlled ZnO thin film is prepared using a low cost electrochemical deposition process at open atmospheric condition. FE-SEM shows that the surface morphology can be altered from nanorods to microplates by adding a chemical additive. XRD analysis confirms that the crystalline growth direction and texture can be controlled by changing the additive concentration during the deposition. Using the optimized ZnO based back reflector (BR) in single junction a-SiGe:H solar cell device, we have achieved external quantum efficiency (EQE) as high as 87% at ∼550 nm; the EQE corrected short circuit current density (JSC) was 20.63 mA cm−2 and solar cell efficiency was 7.73% for the single junction a-SiGe:H solar cell. It proves to us that the high quality ZnO thin films can be produced at much reduced cost using electrochemical deposition for solar cell and other optoelectronic applications.