MORPHOLOGICAL MODIFICATIONS DURING SELECTIVE GROWTH OF INP AROUND CYLINDRICAL AND PARALLELEPIPED MESAS

Morphological modifications during selective epitaxy of InP by hydride vapour phase epitaxy around reactive ion etched stripe mesas as in th e case of edge emitting lasers were studied by growth of alternating l ayers of InP and InP:S. The growth profiles were analysed and compared with the selective growth behaviour around reactive ion etched cylind rical and parallelepiped mesas as in the vertical cavity surface emitt ing lasers. The very initial growth pattern is found to be responsible for the emerging features. The growth along the [110] directions is f aster than that along its orthogonal [110] direction, providing a bett er planarization along the former. Earlier planarization however can c ause mask encroachment, especially in the case of cylindrical mesas, b ut can be suppressed by using wet etched mesas.