Abstract
We report on a study of UVC photonics integrated circuit consisting of monolithically integrated AlxGa1−xN multiple quantum wells based light-emitting diodes, detectors and channel waveguides on sapphire substrates. The waveguide stack consisted of a 1.5 m thick n-Al0.65Ga0.35N waveguide over an AlN (3.5 m thick) clad layer. Using the integrated devices, we estimated the multi-mode ridge waveguide losses to be 23 cm−1 at λemission ∼ 280 nm. We also measured that approximately 80% of the guided light was confined in the n+-Al0.65Ga0.35N layer, 7% in the underlying AlN cladding and the remaining 13% in the double-side polished sapphire substrate.