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A polylithic integration technology is demonstrated for seamless stitching of RF and digital chiplets. In this technology, stitch-chips with compressible microinterconnects (CMIs) are used for low-loss and dense interconnection between chiplets. A testbed using fused-silica stitch-chips with integrated CMIs is demonstrated including modeling, fabrication, assembly, and characterization. A 500 µm-long stitch-chip signal link is measured to have less than 0.4 dB insertion loss up to 30 GHz. A simulated eye diagram for 1000 µm-long stitch-chip signal link has a clear opening at 50 Gbps data rate. Moreover, the S-parameters of the CMIs are extracted from this testbed and show less than 0.17 dB insertion loss up to 30 GHz. Benchmarking to silicon interposer based interconnection is also reported.
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Optimizing epsilon-near-zero based plasmon assisted modulators through surface-to-volume ratio
Plasmonic-based integrated nanophotonic modulators, despite their promising features, have one key limiting factor of large insertion loss (IL), which limits their practical potential. To combat this, we utilize a plasmon-assisted approach through the lens of surface-to-volume ratio to realize a 4-slot based EAM with an extinction ratio (ER) of 2.62 dB/µm and insertion loss (IL) of 0.3 dB/µm operating at ∼1 GHz and a single slot design with ER of 1.4 dB/µm and IL of 0.25 dB/µm operating at ∼20 GHz, achieved by replacing the traditional metal contact with heavily doped indium tin oxide (ITO). Furthermore, our analysis imposes realistic fabrication constraints, and material properties, and illustrates trade-offs in the performance that must be carefully optimized for a given scenario.
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- Award ID(s):
- 1808928
- PAR ID:
- 10531158
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 30
- Issue:
- 11
- ISSN:
- 1094-4087; OPEXFF
- Format(s):
- Medium: X Size: Article No. 19781
- Size(s):
- Article No. 19781
- Sponsoring Org:
- National Science Foundation
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