Chemical beam epitaxy of integrated 1.55 μm lasers on exact and misoriented (1 0 0)-InP substrates

Chemical beam epitaxy (CBE) on patterned substrates is a key technology for integrated optoelectronics. Therefore, it is important to understand the growth kinetics during selective growth. High surface step densities enhance the incorporation of Ga and P. The GaInAsP composition is independent of the width of the grooves for growth on exactly oriented substrates, but not for growth on misoriented substrates. There is a reconstruction of the (1 0 0) surface in narrow grooves when the width of the groove is comparable to the migration length of adsorbed metalorganic molecules. The laser performance obtained (J_th∞ = 420 A cm^-2) is equal to that on epi-ready substrates. A 3 μm wide and 220 μm long integrated device shows a threshold current of 9.5 mA. The device characteristics measured in this work are among the best realised with either CBE or MOVPE.