title: CMOS-compatible, athermal silicon ring modulators clad with titanium dioxide.
abstract: We present the design, fabrication and characterization of athermal nano-photonic silicon ring modulators. The athermalization method employs compensation of the silicon core thermo-optic contribution with that from the amorphous titanium dioxide (a-TiO(2)) overcladding with a negative thermo-optic coefficient. We developed a new CMOS-compatible fabrication process involving low temperature RF magnetron sputtering of high-density and low-loss a-TiO(2) that can withstand subsequent elevated-temperature CMOS processes. Silicon ring resonators with 275 nm wide rib waveguide clad with a-TiO(2) showed near complete athermalization and moderate optical losses. Small-signal testing of the micro-resonator modulators showed high extinction ratio and gigahertz bandwidth.
authors.affiliation: Department of of Electrical and Computer Engineering, University of California, Davis, California 95616, USA. sdjordjevic@ucdavis.edu
authors.forename: Stevan S
authors.initials: SS
authors.lastname: Djordjevic
authors.forename: Kuanping
authors.initials: K
authors.lastname: Shang
authors.forename: Binbin
authors.initials: B
authors.lastname: Guan
authors.forename: Stanley T S
authors.initials: ST
authors.lastname: Cheung
authors.forename: Ling
authors.initials: L
authors.lastname: Liao
authors.forename: Juthika
authors.initials: J
authors.lastname: Basak
authors.forename: Hai-Feng
authors.initials: HF
authors.lastname: Liu
authors.forename: S J B
authors.initials: SJ
authors.lastname: Yoo
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D012666:Semiconductors; D012825:Silicon / Q000737:chemistry*; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D013685:Telecommunications / Q000295:instrumentation*; D014025:Titanium / Q000737:chemistry*
chemical_list: C009495:titanium dioxide; D014025:Titanium; D012825:Silicon