Ultraviolet to mid-infrared optical properties of sputtered Al(Sc)N-on-SiO<inf>2</inf> thin films and experimental demonstration of AlN integrated photonic devices in the telecom C-band

Thin film aluminum nitride (AlN) stands out as a promising material for integrated photonics due to its wide bandgap of 6.1 eV, facilitating efficient operation across diverse spectral ranges. Its inherent electro-optic and nonlinear optical properties make it exceptionally well suited for active photonic components. Compatibility with CMOS technology further strengthens its appeal. Doping AlN with scandium (Sc) in non-centrosymmetric configurations significantly enhances its nonlinear and piezoelectric characteristics. This study explores Al(Sc)N thin films on silicon dioxide (SiO2), investigating optical properties in a broad wavelength range from 0.19 µm to 25 µm. Comprehensive material analysis of sputtered Al(Sc)N films and fabrication techniques for AlN integrated photonic devices demonstrated here highlight AlScN’s potential in integrated photonic applications.