Fabrication of ridge waveguide of 808 nm GaAs-based laser diodes by wet chemical etching

Abstract

The fabrication of ridge waveguide of 808 nm GaAs-based laser diodes by wet chemical etching is investigated. The etching behavior of GaAs, InGaP and AlGaInP in various solutions is evaluated. As a result, the etching solutions simultaneously corroding InGaP and AlGaInP layers are searched successfully. Effects of etching time and the concentration of mixtures on etching depth and the geometrical shape of ridge are analyzed. It is found that under proper conditions, appropriate etching depth and smooth surfaces can be obtained and the steep degree of pattern can be accepted, especially for wide ridge waveguide laser diodes.