  Fully exploiting the silicon photonics platform requires a fundamentally new
approach to realize high-performance laser sources that can be integrated
directly using wafer-scale fabrication methods. Direct band gap III-V
semiconductors allow efficient light generation but the large mismatch in
lattice constant, thermal expansion and crystal polarity makes their epitaxial
growth directly on silicon extremely complex. Here, using a selective area
growth technique in confined regions, we surpass this fundamental limit and
demonstrate an optically pumped InP-based distributed feedback (DFB) laser
array grown on (001)-Silicon operating at room temperature and suitable for
wavelength-division-multiplexing applications. The novel epitaxial technology
suppresses threading dislocations and anti-phase boundaries to a less than 20nm
thick layer not affecting the device performance. Using an in-plane laser
cavity defined by standard top-down lithographic patterning together with a
high yield and high uniformity provides scalability and a straightforward path
towards cost-effective co-integration with photonic circuits and III-V FINFET
logic.
