Optical properties of ultrathin Al2O3/ZnO nanolaminates

• Ultrathin amorphous nanolaminates are very attractive for aerospace application.
• Ultrathin Al2O3/ZnO nanolaminates were deposited by Atomic Layer Deposition.
• Optical and structural properties were investigated.
• Absorption peak decreases and blue shifted with the decrease of bilayer thickness.

Because of their high resistance against ultraviolet and high energy particles, ultrathin amorphous nanolaminates can be very attractive for aerospace application. Here we report on the optical and structural properties of ultrathin Al2O3/ZnO nanolaminates deposited by Atomic Layer Deposition. Structural properties of nanolaminates were studied by GIXRD and AFM. Optical characterization was performed by transmittance, spectroscopic ellipsometry and photoluminescence (PL) spectroscopy. Regression analysis of ellipsometric spectra has shown that absorption peak decreases and blue shifted with the decrease of bilayer thickness in the stack. On the basis of the analysis of structural and optical properties of ultrathin nanolaminates, the amorphous nature of them is suggested.