SBIR Phase II: Foundry-Compatible Silicon-Integrated Epitaxial Barium Titanate Wafers for Silicon Photonics

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase II project is to enable innovators in the area of integrated silicon photonics to experiment with a superior optical material the will result in new approaches, new device architectures, and high density networks that will create technologies that do not exist today as materials available now can’t support such ideas due to current physical limitations. This will be achieved through making available semiconductor fabrication services for special type of materials used in ultra-low power, ultra-fast and ultra-small components at a reasonable cost, with improved manufacturing yields, and reduced development cycle time. The material called Barium Titanate (BaTiO3) can potentially dominate the market for data centers. The BaTiO3-based components are ultra-low power and thus may significantly reduce the power consumption of existing data centers. The work will also support the entirely new markets of quantum and neuromorphic computing. The proposed project will result in the introduction to the market of 200-mm wafers of BaTiO3 on Si for silicon photonics. BaTiO3 alters the speed of light when subjected to electric field more efficiently than almost any other material. The company will develop chemical mechanical polishing and wafer bonding processes, including the necessary process design kits (PDKs) compatible with a standard silicon photonic foundry. This will enable hundreds of small to medium photonic companies to innovate with superior modulator material and new automation tools. The characteristics of BaTiO3 will qualitatively change what is possible with integrated, on-chip optical networks. The work will focus on transferring the 50-mm process developed in Phase I to a 200-mm wafer. The innovative deposition technique will enable mass production of such wafers. The company then will work with a subcontractor to understand the chemistry, particle size of the slurry and velocity and pressure of the process to produce BaTiO3 wafers with less than 0.5 nm roughness necessary for wafer bonding. This will enable the device builders to use already existing device architecture fabricated in Si or SiN in heterogeneous integration with BTO. 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.