title: Sub-1 dB/cm submicrometer-scale amorphous silicon waveguide for backend on-chip optical interconnect.
abstract: We demonstrate a submicrometer-scale hydrogenated amorphous silicon (a-Si:H) waveguide with a record low propagation loss of 0.60 ± 0.02 dB/cm because of the very low infrared optical absorption of our low defect a-Si:H film, the optimized waveguide structure and the fabrication process. The waveguide has a core with a thickness of 440 nm and a width of 780 nm that underlies a 100-nm-thick ridge structure, and is fabricated by low-cost i-line stepper photolithography and with low-temperature processing at less than 350°C, making it compatible with the backend process of complementary metal oxide semiconductor (CMOS) fabrication.
authors.forename: Ryohei
authors.initials: R
authors.lastname: Takei
authors.forename: Shoko
authors.initials: S
authors.lastname: Manako
authors.forename: Emiko
authors.initials: E
authors.lastname: Omoda
authors.forename: Youichi
authors.initials: Y
authors.lastname: Sakakibara
authors.forename: Masahiko
authors.initials: M
authors.lastname: Mori
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Kamei