CW operation of III-V microdisk lasers on SOI fabricated in a 200 mm CMOS pilot line

Compact InP-based microdisk lasers on SOI completely fabricated in a 200 mm CMOS pilot line are presented. Continuous wave operation is demonstrated with threshold currents of 600 muA and 31 muW output power

Characterization of ferroelectric hafnium/zirconium oxide solid solutions deposited by reactive magnetron sputtering

International audienceThe room temperature deposition of 10 nm-thick ferroelectric hafnium/zirconium oxide, (Hf, Zr)O 2 , thin solid films is achieved with a single hafnium/zirconium, Hf/Zr, alloy target by reactive magnetron sputtering. After rapid thermal annealing (RTA), crystallization of our samples is analyzed by grazing incidence x-ray diffraction. Changing the pressure inside the chamber during deposition leads to grow amorphous or monoclinic phase (m-phase). The authors demonstrate that if the (Hf, Zr)O 2 films are crystallized in the m-phase after deposition, no ferroelectric/orthorhombic phase can be obtained further. On the contrary, when the as-deposited film is amorphous, the ferroelectric/orthorhombic phase appears after the RTA. Published by the AVS. https://doi.org/10.1116/1.506064

Compact integration of optical sources and detectors on SOI for optical interconnects fabricated in a 200 mm CMOS pilot line

As the demand for bandwidth increases, optical interconnects are coming closer and closer to the chip. Optical interconnects on silicon-on-insulator (SOI) are desirable as this allows for integration with CMOS and the mature processing can be used for photonic integrated circuits. A heterogeneous integration process can be used to include III-V active optical components on SOI. For dense integration compact sources and detectors are required, but they typically need different epitaxial structures to be efficient which limits the integration density. We propose to use an epitaxial structure, which contains both the layers for a laser and for a detector, hereby enabling very compact integration of sources and detectors. Microdisk lasers and waveguide detectors using this epi were completely fabricated in a 200 mm CMOS pilot line and the results are discussed here

Electro-Optical Modulation Based on Pockels Effect in BaTiO3 With a Multi-Domain Structure

[EN] The influence of an in-plane multi-domain structure in BaTiO3 films grown on SrTiO3/Si buffers for highly efficient electro-optic modulation has been analyzed. The modulation performance can be significantly enhanced by rotating a certain angle, the optical waveguide, with respect to the BaTiO3 crystallographic axes. A robust electro-optical performance against variations in the domain structure as well as the lowest V-pi voltage can be achieved by using the rotation angles between 35 degrees and 55 degrees. Our calculations show that Vp voltages below 1.7 V for a modulation length of 2 mm can be obtained by means of a CMOS compatible hybrid silicon/BaTiO3 waveguide structure.This work was supported by the European Commission under Grant FP7-ICT-2013-11-619456 SITOGA. The work of P. Sanchis was supported in part by GVA under Grant PROMETEOII/2014/034 and in part by the Ministerio de Economia y Competitividad under Grant TEC2012-38540 LEOMIS.Castera, P.; Gutiérrez Campo, AM.; Tulli, D.; Cueff, S.; Orobtchouk, R.; Rojo Romeo, P.; Saint-Girons, G.... (2016). Electro-Optical Modulation Based on Pockels Effect in BaTiO3 With a Multi-Domain Structure. IEEE Photonics Technology Letters. 28(9):990-993. https://doi.org/10.1109/LPT.2016.252250999099328

Low-Loss and Compact Silicon Rib Waveguide Bends

[EN] Waveguide bends support intrinsically leaky propagation modes due to unavoidable radiation losses. It is known that the losses of deep-etched/strip waveguide bends increase inevitably for decreasing radius. Here, we theoretically and experimentally demonstrate that this result is not directly applicable to shallow-etched/rib waveguide bends. Indeed, we show that the total losses caused by the bends reach a local minimum value for a certain range of compact radii and rib waveguide dimensions. Specifically, we predicted the minimum intrinsic losses < 0.1 dB/90 degrees turn within the range of 25-30 mu m bend radii in a 220 nm-thick and 400 nm-wide silicon rib waveguide with 70 nm etching depth. This unexpected outcome, confirmed by experimental evidence, is due to the opposite evolution of radiation (bending) losses and losses caused by the coupling to lateral slab modes (slab leakage) as a function of the bend radius, hence creating an optimum loss region. This result may have important implications for the design of compact and low-loss silicon nanophotonic devices.This work was supported in part by the European STREP Program under Grant FP7-ICT-2013-11-619456-SITOGA and Grant FP7-ICT-2012-10-318240 PhoxTroT and in part by LEOMIS under Grant TEC2012-38540. (Corresponding author: Regis Orobtchouk.)Brimont, ACJ.; Hu, X.; Cueff, S.; Rojo-Romeo, P.; Saint Girons, G.; Griol Barres, A.; Zanzi, A.... (2016). Low-Loss and Compact Silicon Rib Waveguide Bends. IEEE Photonics Technology Letters. 28(3):299-302. https://doi.org/10.1109/LPT.2015.2495230S29930228