Epitaxial Lateral Overgrowth has been proposed as a key technology of a novel hybrid integration platform for active silicon photonic components. By fabricating silicon oxide mask on top of a thin InP seed layer, we can use the so called defect necking effect to filter out the threading dislocations propagating from the seed layer. By optimizing the process, thin dislocation free InP layers have been successfully obtained on top of silicon wafer. The obtained characterization results show that the grown InP layer has very high quality, which can be used as the base for further process of active photonic components on top of silicon.