A study of wet oxidized A1xGa1-xAs for integrated optics

An investigation of wet oxidized Al-x Ga1-xAs layers in integrated optical applications is reported, Refractive index and thickness shrinkage of wet oxidized AI(x)Ga(1-x)As layers are measured using spectroscopic ellipsometry, A Cauchy fit to the refractive index is found in the wavelength range between 0.3 and 1.6 mu m. The refractive index at 1.55 mu m is found to be 1.66+/-0.01 with little dispersion around 1.55 mu m. Very low loss single-mode waveguides with metal electrodes showing very low polarization dependence of loss coefficient are fabricated using wet oxidized AlxGa1-xAs layers as upper cladding, Optical polarization splitters are also designed and fabricated from the same type of waveguides taking advantage of increased birefringence, Designs utilizing wet oxidized AlxGa1-xAs are compared with conventional designs using only compound semiconductor heterostructures.