Hot wire chemical vapor deposition for silicon photonics: An emerging industrial application opportunity

• Published in: Thin solid films 2019-04, Vol.676, p.26-30
• Main Authors: Tarazona, A., Bucio, T. Domínguez, Oo, S.Z., Petra, R., Khokhar, A.Z., Boden, Stuart A., Gardes, F.Y., Reed, G.T., Chong, H.M.H.
• Format: Article
• Language: English
• Subjects: Hot wire chemical vapor deposition; Mach-Zehnder interformeter; Multimode interferometer; Silicon nitride; Silicon photonics; Silicon photonics waveguides
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2019.02.048

In this work different silicon photonic devices, including straight waveguides, multi-mode interference devices and Mach-Zehnder interferometers, were fabricated and characterized on hot-wire chemical vapor deposition (HWCVD) silicon nitride (SiN) layers deposited at temperatures below 350 °C. These layers presented a hydrogen concentration of 13.1%, which is lower than that achieved with plasma enhanced chemical vapor deposition at these deposition temperatures. The lowest reported optical propagation losses of 6.1 dB/cm and 5.7 dB/cm, 1550 nm and 1310 respectively, for straight SiN waveguides prepared by HWCVD was measured. We demonstrated that silicon nitride SiN, prepared using HWCVD, is a viable material for silicon photonics fabrication. •Silicon nitride (SiN) films were prepared by Hot Wire Chemical Vapor Deposition.•Their morphology and H2 were assessed to elucidate sources of propagation losses.•Propagation losses of 6.1 dB/cm were measured on the HWCVD SiN waveguides.•Multimode interferometers with propagation losses of 5.2 dB were fabricated.•Built Mach-Zehnder interferometers showed free-spectral ranges of 7 and 15 nm.