Fabrication and integration of photonic devices for phase-change memory and neuromorphic computing

Highlights The fabrication of photonic integrated devices based on phase-change materials (PCMs) is introduced, including electron beam lithography, reactive ion etching, ion implantation and magnetron sputtering. The working principles, fabrication flows, and device performances are elaborated for the suspended waveguide platforms, photonic memory elements, waveguide microheaters and plasmonic nanogap devices. The interconnection of high-performance memory cells and their applications are discussed, including associative learning and matrix-vector multiplication. The opportunities and challenges are envisioned in developing a back-end-of-line technology compatible with the silicon photonic CMOS line for integrating PCM memory.