The Influence of Intermittent Growth Procedures on Dislocation Densities in InP Epi-layers

The influence of intermittent growth procedures on dislocation densities in iso-epitaxial layers, grown on highly dislocated (001) InP substrates by LPE, has been assessed using etch pitting. It is observed that the incorporation of an isothermal hold in the growth sequence reduces the density of dislocations in the epi-layer. The major reduction occurs during growth following the isothermal arrest. However, the interrupted growth schemes involving partial melt-back of an epi-layer as well as melt-back followed by an isothermal hold are not effective in reducing the dislocation density. It is generally agreed that the performance, reliabil-ity, and degradation behavior of opto-electronic de-vices are affected by the presence of dislocations (1-7). Olsen (2) has investigated the influence of interracial lattice mismatch on I I I-V compounds on device per-formance. It is found that the increased mismatch as deleterious effects on the electro-optical properties of transmission photocathode and transmission secondar