Abstract
In this paper, we present a simulation study that intends to characterize the influence of defects introduced by manufacturing processes on the geometry of a semiconductor structure suitable to be used as a multimode interference (MMI) 3 dB power splitter. Consequently, these defects will represent refractive index fluctuations which, on their turn, will drastically affect the propagation conditions within the structure. Our simulations were conducted on a software platform that implements the Beam Propagation numerical method. This work supports the development of a biomedical plasmonic sensor, which is based on the coupling between propagating modes in a dielectric waveguide and the surface plasmon mode that is generated on an overlaid metallic thin film, and where the output readout is achieved through an a-Si:H photodiode. By using a multimode interference 1 × 2 power splitter, this sensor device can utilize the non-sensing arm as a reference one, greatly facilitating its calibration and enhancing its performance. As the spectral sensitivity of amorphous silicon is restricted to the visible range, this sensing device should be operating on a wavelength not higher than 700 nm; thus, a-SiNx has been the material hereby proposed for both waveguides and MMI power splitter.
Highlights
Introduction aSiNx is considered a promising platform for photonic integrated circuits (PIC) as PICs can be fabricated in state-of-the-art foundries with integrated CMOS electronics [1,2]
We performed the analysis of a symmetric interference multimode interference (MMI) device tolerance to manufacturing deviations in CMOS photonics
MMI devices have been used in many real life applications as splitters, combiners and couplers but MMI devices have been used in many real life applications as splitters, combiners and couplers usually on telecommunications operating wavelengths
Summary
SiNx is considered a promising platform for photonic integrated circuits (PIC) as PICs can be fabricated in state-of-the-art foundries with integrated CMOS electronics [1,2]. The high index contrast between a-SiNx and silicon dioxide allows the production of submicron cross section waveguides and very small bending radii, enabling high density integration. While much of the existing work on CMOS photonics [1,2] has used directional couplers for power splitting, multimode interference (MMI) devices may have relaxed fabrication requirements and smaller footprints [3], when compared to other configurations based on parallel waveguides coupling. MMI devices have already been used as 1 × 2 splitters, 2 × 1 combiners in Quadrature Phase Shift Keying (QPSK) modulators [4],. State-of-the-art CMOS manufacturing processes may achieve nanometer scale lithographic precision.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
