A CMOS compatible material platform for photonic integrated circuitry is invented. The material platform has SiO2 as cladding material, at least a bottom layer made of moderate refractive index material(s) fabricated first on a unpatterned SOI wafer, a bonded system substrate, a set of photonic circuitry made within a SOI layer of the SOI wafer after its substrate and BOX layer removed, and some coupling devices enabling light travelling between the devices made within these two layers. A solution to provide IIIV laser diodes boned and embedded in the system substrate is also proposed. The invention provides a great material platform to offer full set of photonic building blocks for all sort of different applications such as photonic circuitry for optical neural network, quantum computing, telecommunication, data communication, optical switching, optical sensing, passive and/or active Si optical interposer with its size even bigger than lithography step field size.