CMOS pilot line – Imec and Ghent University: Breakthrough marks step towards next-generation photonic integrated circuit technology
Imec and Ghent University have presented, for the first time, arrays of InP lasers monolithically integrated on 300mm silicon substrates in a CMOS pilot line.
This breakthrough, published in Nature Photonics, provides a path toward high-volume manufacturing of cost-effective photonic integrated circuits (PICs) with monolithically integrated laser sources. Such laser-powered PICs could change the way data is transferred between future logic and memory chips.
Over the past few years, demand for data communication between servers in cloud datacentres has been growing exponentially, following strong growth in social networking, cloud computing and big data applications.
Silicon photonics technology enables cost-effective manufacturing of fibre-optic transceivers, which in turn provides continued scaling of server and datacentre capacity with improved power efficiencies. However, wide-spread adoption of this technology has been hampered in part by the lack of monolithically integrated laser sources.
The integration on silicon of efficient INP based light sources, currently driving long-range telecommunication networks, is known to be very challenging, owing to the large mismatch in crystal lattice constants between both materials.
Imec and Ghent University overcame these structural differences and largely suppressed the detrimental crystal defects that typically form at the interface between silicon and InP. Using a production grade MOVPE growth reactor, InP semiconductor was selectively grown on silicon in a pre-patterned oxide template, realising InP waveguide arrays across the entire 300mm substrate. Subsequently, periodic grating structures were etched in the top layer of these waveguides, providing the optical feedback required for laser operation.Read more