STRAIN-COMPENSATED INASP GAINP MULTIPLE-QUANTUM-WELL WAVE-GUIDE MODULATORS AND IN-SITU MONITORED ALGAAS/ALAS MIRRORS GROWN BY GAS-SOURCE MOLECULAR-BEAM EPITAXY/

Gas-source molecular beam epitaxy (MBE) is used to grow high-quality s train-compensated InAsxP1-x/GayIn1-yP multiple quantum wells on InP su bstrates for modulator applications at 1.3 mu m wavelength. The compos ition of the InAsxP1-x well can be determined in situ by the As-to-In incorporation ratio from As-and In-induced intensity oscillations of r eflection high-energy electron diffraction. Tensile GayIn1-yP is used to compensate the compressive strain in the InAsP. A modified doping p rofile in a waveguide modulator is used to provide a better confinemen t of the depletion region in the p-i-n structure under reverse bias. A n improved quantum-confined Stark effect is obtained. In situ monitori ng and controlling reflectivity of the AlGaAs/AlAs quarter-wave mirror s is used for reflection-type modulators on GaAs. (C) 1997 Published b y Elsevier Science S.A.