SiN half-etch horizontal slot waveguides for integrated photonics: numerical modeling, fabrication, and characterization of passive components

Eva Kempf (1, 2) , Pedro Rojo Romeo (2) , Alban Gassenq (3) , Arnaud Taute (1, 2) , Paul Chantraine (1) , Jimmy John (2) , Ali Belarouci (2) , Stephane Monfray (1) , Frederic Boeuf (1) , Paul Charette (4) , Régis Orobtchouk (2)

1 ST-CROLLES - STMicroelectronics [Crolles]
2 INL - I-Lum - INL - Ingénierie et conversion de lumière (i-Lum)
3 iLM - MNP - iLM - Matériaux et nanostructures photoniques
4 LN2 - Laboratoire Nanotechnologies et Nanosystèmes [Sherbrooke]

This work presents a “half-etch” horizontal slot waveguide design based on SiN, where only the upper SiN layer is etched to form a strip that confines the mode laterally. The numerical modeling, fabrication, and characterization of passive waveguiding components are described. This novel slot waveguide structure was designed with on-chip light amplification in mind, for example with an Er-doped oxide spacer layer. Proof-of-concept racetrack resonators were fabricated and characterized, showing quality factors up to 50,000 at critical coupling and residual losses of 4 dB/cm at wavelengths away from the N-H bond absorption peak in SiN, demonstrating the high potential of these horizontal slot waveguides for use in active integrated photonics.

Domaines: Sciences de l'ingénieur [physics]; Chimie; Physique [physics]

Eva Kempf, Pedro Rojo Romeo, Alban Gassenq, Arnaud Taute, Paul Chantraine, et al.. SiN half-etch horizontal slot waveguides for integrated photonics: numerical modeling, fabrication, and characterization of passive components. Optics Express, 2022, 30 (3), pp.4202-4214. ⟨10.1364/OE.446758⟩. ⟨hal-03574485⟩