CMOS-compatible, plasma beam assisted reactive magnetron sputtered silicon nitride films for photonic integrated circuits

In this contribution, we demonstrate the deposition of low loss, CMOS-compatible SiN thin-films using plasma beam assisted reactive sputtering for photonic integrated circuits. Plasma beam assistance during the deposition process enabled us to achieve thin-film losses of below 0.1 dB/cm and a surface roughness of Rq of <0.1 nm, while keeping the processing temperatures below 400°C. Propagation losses of 0.9 dB/cm at 1550 nm have been achieved for waveguides with a cross section of 460× 2000 nm (height × width).