GSMBE growth on patterned substrates for optoelectronic devices

Some aspects of the regrowth process of InP-based materials by gas source molecular-beam epitaxy (GSMBE) are presented. The regrowth on patterned substrates with different mesa features is discussed. Two device examples which highlight lift-off technologies using either dielectric or semiconductor lift-off masks to enable selective removal of unwanted epitaxial material are presented. A process which uses GSMBE for the realization of butt-coupled laser-waveguide structures is introduced. The results obtained demonstrate a coupling efficiency of greater than 80% between passive and active waveguides and passive region losses of approximately 15 cm/sup -1/ in broad area laser structures. Additionally, using a similar process, buried-heterostructure lasers have been fabricated. >