A new sol-gel route to prepare dense Al2O3 thin films

Anew sol-gel route has been applied to synthetize dense Al2O3thin films from aluminum isopropoxide (Al(OPri)3)as raw precursor material. The results show that, in the solution, acetylacetone (AcAc) and aluminum form a complex compound which effectively suppresses the growth of colloidal particles and makes the sol very stable. Al2O3thin films fabricated by spin-coating method and calcined at 500 °C for 3 h possess an amorphous structure and exhibit a highly homogeneous surface texture without evidence of holes or cracks throughout the film. Moreover, the prepared films display a low leakage current and a high transmittance. This new sol-gel route appears to be a highly promising method to synthetize dense Al2O3 thin films from Al(OPri)3, and could provide a wide range of optical and electric applications.