Efficient method and layer design for calibrating compositions and growth rates of AlGaInP layers in 660-nm laser diodes grown by MOCVD

We propose an efficient method and a layer design to reproducibly calibrate the growth rate and composition of AlGaInP layers grown on GaAs substrates by metalorganic chemical vapor deposition using an in situ reflection monitoring system. Owing to the proposed method, the (Al, Ga) composition and the strain of AlGaInP layers were accurately controlled with a standard variation of the strain of as low as ±0.02%. In addition, we developed a layer design, which allowed calibrating the growth rates and compositions of a number of layers in laser diode structures by a single growth run, in conjunction with the proposed method. As a result, the standard deviations of indium composition for (Al0.70Ga0.30)0.51In0.49P layers, photoluminescence peak wavelength for waveguide (Al0.50Ga0.50)0.51In0.49P layers and GaInP/(Al0.50Ga0.50)0.51In0.49P multi-quantum wells were observed to be 0.001, 0.39, and 0.82 nm, respectively, for as many as 48 growth runs of 660-nm laser diode full structures with eight preventive maintenances in between. Consequently, these small variations demonstrate that the proposed calibration method and layer design are adequate for growing AlGaInP layers with an accurate composition and thickness control without performing many pre-test runs for all the layers LD structures in practice.