title: Design and fabrication of 3μm silicon-on-insulator waveguide integrated Ge electro-absorption modulator.
abstract: We present the design and fabrication of a waveguide-based Ge electro-absorption (EA) modulator integrated with a 3 µm silicon-on-isolator (SOI) waveguide. The proposed Ge EA modulator employs a butt-coupled horizontally-oriented p-i-n structure. The optical design achieves a low-loss transition from Ge to Si waveguides. The interaction between the optical mode of the waveguide and the bias induced electric field in the p-i-n structure was maximized to achieve high modulation efficiency. By balancing the trade-offs between the extinction ratio and the insertion loss of the device, an optimal working regime was identified. The measurement results from a fabricated device were used to verify the design. Under a -4Vpp reverse bias, the device demonstrates a total insertion loss (including the transition loss) of 2.7-5.2 dB and an extinction ratio of 4.9-8.2 dB over the wavelength range of 1610-1640 nm. Subtracting the contribution of the transition loss, the Δα/α value for the fabricated device was estimated to be between 2.2 and 3.2 with an electric field around 55 kV/cm.
authors.affiliation: Kotura Inc., Monterey Park, CA 91754, USA. nfeng@turkoa.com
authors.forename: Ning-Ning
authors.initials: NN
authors.lastname: Feng
authors.forename: Shirong
authors.initials: S
authors.lastname: Liao
authors.forename: Dazeng
authors.initials: D
authors.lastname: Feng
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.forename: Po
authors.initials: P
authors.lastname: Dong
authors.forename: Hong
authors.initials: H
authors.lastname: Liang
authors.forename: Cheng-Chih
authors.initials: CC
authors.lastname: Kung
authors.forename: Wei
authors.initials: W
authors.lastname: Qian
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Joan
authors.initials: J
authors.lastname: Fong
authors.forename: Roshanak
authors.initials: R
authors.lastname: Shafiiha
authors.forename: Ying
authors.initials: Y
authors.lastname: Luo
authors.forename: Jack
authors.initials: J
authors.lastname: Cunningham
authors.forename: Ashok V
authors.initials: AV
authors.lastname: Krishnamoorthy
authors.forename: Mehdi
authors.initials: M
authors.lastname: Asghari
mesh_terms: D017076:Computer-Aided Design; D004553:Electric Conductivity; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005857:Germanium / Q000737:chemistry*; D055096:Optical Devices; D012031:Refractometry / Q000295:instrumentation*; D012666:Semiconductors; D012825:Silicon / Q000737:chemistry*; D018511:Systems Integration; D013685:Telecommunications / Q000295:instrumentation*
chemical_list: D005857:Germanium; D012825:Silicon