ALD high-k layer grating couplers for single and double slot on-chip SOI photonics
2012 (English)In: Solid-State Electronics, ISSN 0038-1101, E-ISSN 1879-2405, Vol. 74, 58-63 p.Article in journal (Refereed) Published
State of the art grating couplers for horizontal single and double slot waveguides are presented; in these devices the input signal is transmitted from a single mode optical fiber to silicon on insulator slot waveguide. In the waveguides, atomic layer deposited (ALD) high-k dielectrics form the low refractive index slot. It is demonstrated that a fully etched design combined with precision of ALD result in highly reproducible devices with theoretical efficiency variations less than 1%. Devices have a peak calculated coupling efficiency of 24% at 1.55 mu m. In order to achieve an optimal design, optical properties of high-k films are studied by spectroscopic ellipsometry. Measured refractive indices show variations from reference values, originated from film variation in densities. Chips with a test slot material are fabricated and the optical efficiency of the couplers is characterized. The maximum measured coupling efficiency of the couplers is 18.5%.
Place, publisher, year, edition, pages
2012. Vol. 74, 58-63 p.
Integrated photonics, Grating couplers, High-k thin films, Slot waveguides, Fabrication and characterization
IdentifiersURN: urn:nbn:se:kth:diva-99216DOI: 10.1016/j.sse.2012.04.012ISI: 000305728600011ScopusID: 2-s2.0-84861899154OAI: oai:DiVA.org:kth-99216DiVA: diva2:541999
QC 201207272012-07-272012-07-232014-11-14Bibliographically approved