SBIR Phase II: Foundry-scale production of on-chip silicon photonic light emitters enabled by printed photonic ink

This Small Business Innovation Research Phase II project will develop black phosphorus-based inks to create on-chip embedded lasers, enabling fully functional silicon photonic (SiP) chips. Silicon is the fastest-growing material choice for photonic chip products because SiP leverages the foundry-processing capabilities that have been built for the electronics industry over decades. Currently, the primary laser solution being employed in SiP uses off-chip bonded lasers where system integrators assembling SiP products rely on a cumbersome method of bonding individual lasers to silicon chips. The main on-chip approach, heterogeneous integration of III-V materials bonded to silicon, was developed for a single spectral band for optical communications and is challenging for adoption in broader markets. The lack of a scaled-up method for fabricating multi-spectral band, silicon-compatible lasers is a major unsolved problem for the $1 billion-per-year SiP market. The technical leap envisioned in this effort will be a key enabling technology of photonic chips that will first be supplied to support defense customers and wearable medical sensor developers to generate more physiological data per dollar and drastically shrink the size and weight of such sensors. This will mean smaller, lighter aircraft and flexible, wearable sensors in applications where the size and cost have historically been too high. The intellectual merit of this project builds upon Phase I results that showed a minimum viable prototype photodiode component with a state-of-the-art photo response of 800 mA/W under 980 nm illumination. This milestone was enabled by a new method for creating inks and ink-printed films with high-quality opto-electronic properties. Importantly, the electronic quality of the inks was increased to commercially viable levels and the current improved to levels on par with commercially available LEDs. While this work established the feasibility of the approach, further technical demonstrations in light emission are required to validate the technology and position it for investment and commercial launch via integration into foundry libraries for use by defense companies, medical device manufacturers, and beyond. In Phase II, photonic inks emitting at 1450 nm will be integrated directly onto a foundry chip to demonstrate critical on-chip laser components demanded by the Integrated Photonics Systems Roadmap (IPSR). This achievement will demonstrate the scalability of the approach and increase the viability of photonic integrated circuits as a platform for developing sensors. Photodetection will also be explored to further expand the impact of ink-printed components. This will close the loop of silicon-based photonic integrated circuits, enabling large-scale production and implementation of this potentially transformative technology. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.