Scalability is essential for advancing nanophotonic systems in quantum information technologies and communication. Semiconductor QDs are leading candidates for single-photon generation due to their compatibility with established epitaxial growth methods, such as MOCVD on GaAs and InP substrates. However, their self-organizing growth limits deterministic device fabrication, while achieving quantum properties requires cryogenic temperatures and coherent optical excitation, posing additional challenges. To overcome these limitations, my work employs an epitaxial method with buried stressors, enabling precise spatial control of QD growth on etched mesa structures. This approach facilitates both high-density QDs for microlasers and low-density QDs for single-photon sources (SPS). By enabling stacked QD layers, this method ensures high spatial overlap between site-controlled QDs (SCQDs) and micropillar resonator modes, enhancing coupling efficiency and reducing optical losses. Furthermore, strain-induced spectral nanoengineering shifts SCQD emission into the telecommunication O-band (1260 – 1270 nm), producing emitters with excellent quantum properties and stable single-photon emission up to 70 K, suitable for compact cryostat-based quantum communication. To address the limitations of GaAs- and InP-based devices, this work demonstrates direct QD integration on silicon substrates using a GaP buffer layer