Aluminum scandium nitride on 8-inch Si wafers: material characterization and photonic device demonstration

The anisotropic optical properties of aluminum scandium nitride (Al_1-xScxN) thin films for both ordinary and extraordinary light are investigated. A quantitative analysis of the band structures of the wurtzite Al_1-xScxN is carried out. In addition, Al_1-xScxN photonic waveguides and bends are fabricated on 8-inch Si substrates. With x = 0.087 and 0.181, the light propagation losses are 5.98 ± 0.11 dB/cm and 8.23 ± 0.39 dB/cm, and the 90° bending losses are 0.05 dB/turn and 0.08 dB/turn at 1550 nm wavelength, respectively.