Abstract

Currently, prism couplers are often used to measure the mode indices of glass and LiNbO₃ waveguides.¹ Recently, silicon prisms were also used to measure InP and InGaAsP waveguides.^2,3 However, buried waveguides cannot be measured by prism couplers. The high refractive index of semiconductor waveguides also makes the measurement difficult over a wide wavelength range. In this paper, a new non-destructive and non-contact measuring technique that can accurately measure the mode indices (N) of single mode GaAs/AlGaAs slab waveguides is presented. This measurement technique could be a useful tool for wafer selection in the fabrication of distributed feedback laser.

© 1991 Optical Society of America