(Invited) Rare Earth Doped Light Emitting Thin Film Materials for Silicon Photonics

Silicon photonic technology is becoming ubiquitous for data center, sensing and advanced photonic applications. However, one of the key challenges for silicon photonic microsystems is integrating materials which can provide optical gain. The leading approach involves hybrid bonding of III-V materials to silicon chips, which is expensive and difficult to scale. Alternatively, rare-earth-doped materials are promising for active device applications on silicon. Rare earth doped oxide thin films can be deposited using standard, low-cost, and wafer-scale methods directly on silicon and emit light in important bands for communications and other emerging applications. This presentation will cover recent progress on integrating rare-earth-doped materials into silicon photonic microsystems. It will focus on fabrication and integration methods, particularly reactive magnetron co-sputtering, which yields low-loss, high-gain thin films which can be deposited using a single post-processing step onto silicon photonic chips that have been fabricated in a silicon foundry. The fabrication challenges, spectroscopic properties, and device design requirements related to prospective materials, including ytterbium-, erbium- and thulium-doped oxides will be discussed. The talk will review the application of such films in light-emitting rare-earth-doped devices, including amplifiers and continuous-wave and pulsed lasers.