(Al, In)GaN laser diodes with optimized ridge structures

We develop (Al, In)GaN ridge waveguide laser diodes in the violet-blue spectral region. Varying the indium content of the InGaN quantum wells, we tailor the emission wavelength of our devices for specific applications in the range from 390 nm to 425 nm. Using different commercially available free standing GaN substrates, we adjust the epitaxial design and optimize the processing sequence for the different kinds of substrates. In particular we focus on the ridge formation. We compare different fabrication methods to obtain devices with ridge widths around <=2 µm. So far, we have achieved threshold currents around 60 mA and slope efficiencies exceeding 1 W/A