Arbitrary Coupling Ratio Multimode Interference Couplers in Silicon-on-Insulator

In this paper, we present the design, manufacturing, characterization, and analysis of the coupling ratio spectral response for multimode interference couplers in silicon-on-insulator (SOI) technology. The couplers were designed using a Si rib waveguide with SiO2 cladding, on a regular 220 nm film a...

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Bibliographic Details
Authors: Doménech Gómez, José David, Sánchez Fandiño, Javier Antonio, Gargallo Jaquotot, Bernardo Andrés, P. Muñoz|||0000-0001-6026-1649
Format: article
Publication Date:2014
Country:España
Institution:Universitat Politècnica de València (UPV)
Repository:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Language:English
OAI Identifier:oai:riunet.upv.es:10251/57567
Online Access:https://riunet.upv.es/handle/10251/57567
Access Level:Open access
Keyword:Coupling ratio
Multimode interference coupler
Performance statistics
Silicon-on-insulator (SOI)
Variation analysis
TEORIA DE LA SEÑAL Y COMUNICACIONES
Description
Summary:In this paper, we present the design, manufacturing, characterization, and analysis of the coupling ratio spectral response for multimode interference couplers in silicon-on-insulator (SOI) technology. The couplers were designed using a Si rib waveguide with SiO2 cladding, on a regular 220 nm film and 2 μm buried oxide SOI wafer. A set of eight different designs, three canonical and five using a widened/narrowed coupler body, have been subject of study, with coupling ratios 50:50, 85:15, and 72:28 for the former, and 95:05, 85:15, 75:25, 65:35, and 55:45 for the latter. Two wafers of devices were fabricated, using two different etch depths for the rib waveguides. A set of six dies, three per wafer, whose line metrology matched the design, were retained for characterization. The coupling ratios obtained in the experimental results match, with little deviations, the design targets for a wavelength range between 1525 and 1575 nm, as inferred from spectral measurements and statistical analyses. Excess loss for all the devices is conservatively estimated to be approximately 0.6 dB in average. All the design parameters, body width and length, input/output positions and widths, and tapers dimensions are disclosed for reference.