Silicon micro photonics includes photonics and silicon microelectronics components, which is rapidly evolving in various optical systems. It employs at least two different materials with a large differential index of refraction to squeeze the light down to a small size. We have shown that by ultra-dense coupling of photonic crystal (PhC) nanocavity lasers, the differential quantum efficiencies can be improved dramatically with large spontaneous emission coupling factor beta, without sacrificing the low lasing thresholds of single Ph C nanocavity lasers. This could not have been achieved by coupling lasers with small beta. The status of silicon microphotonics and the recent advances that cause people to be optimistic to the realization of an active silicon light source has been also discussed. As soon as this objective gets realized, all the major building blocks for monolithic silicon microphotonics will become available. The final vision is to have Silicon microphotonics participating in every global application of the photonics industry. We indeed propose silicon as the unifying material where the next generation of photonics devices will be realized. In this paper, the behavior of nanocavity array laser and Raman silicon laser is discussed. Finally, we studied the laser behavior theoretically and shown that the benefits obtained from the coupling of cavities are due to the strong cavity effects such as the enhanced spontaneous emission rate.