Leur récente résurgence dans la mémoire de la population locale, qui s'est entre autres manifestée par la nomination d'un boulevard en leur honneur, et la persistance de mythes les concernant auront ...incité Kathleen Durocher a s'interroger sur leur histoire. Par ailleurs, de nombreux journaux et périodiques, divers fonds gouvernementaux (Ottawa, Québec, Ville de Hull/Gatineau) et privés, notamment le fonds William Lyon Mackenzie King, les archives des Oblats (fonds Deschâtelets), celui de la Confédération des syndicats nationaux, etc., lui permettent de revenir sur l'usage, puis l'interdiction du phosphore blanc dans la fabrication des allumettes et sur la mobilisation des allumettieres au sein d'un syndicat catholique. Le phénomene, maintes fois signalé par les historiennes, est ici pleinement mis au jour, les données des recensements nominatifs du xixe siecle offrant un contraste frappant avec les déclarations de la compagnie.
Silicon ring resonator-based devices, such as modulators, detectors, filters, and switches, play important roles in integrated photonic circuits for optical communication, high-performance computing, ...and sensing applications. However, the high sensitivity to fabrication variations has limited their volume manufacturability and commercial adoption. Here, we report a low-cost post-fabrication trimming method to tune the resonance wavelength of a silicon ring resonator and correct for fabrication variations at wafer-scale. We use Ge implant to create an index trimmable section in the ring resonator and an on-chip heater to apply a precise and localized thermal annealing to tune and set its resonance to a desired wavelength. We demonstrate resonance wavelength trimming of ring resonators fabricated across a 300 mm silicon-on-insulator (SOI) wafer to within 32 pm of a target wavelength of 1310 nm, providing a viable path to high-volume manufacturing and opening up new practical applications for these devices.
Invited for the cover of this issue is the group of Danqing Liu and co‐workers at the University of Eindhoven University of Technology. The image depicts two‐step photopolymerization‐induced ...diffusion for the fabrication of gradient‐structured dual‐responsive thiol‐ene networks. Read the full text of the article at 10.1002/chem.202400515.
“Gradient‐structured actuators can work in various environments, and the degree of actuation can be controlled by carefully tailoring the photopolymerization conditions.” This and more about the story behind the front cover can be found in the article at 10.1002/chem.202400515).
The development of stretchable electronic devices is a critical area of research for wearable electronics, particularly electronic textiles (e-textiles), where electronic devices embedded in clothing ...need to stretch and bend with the body. While stretchable electronics technologies exist, none have been widely adopted. This work presents a novel and potentially transformative approach to stretchable electronics using a ubiquitous structure: the helix. A strip of flexible circuitry ('e-strip') is twisted to form a helical ribbon, transforming it from flexible to stretchable. A stretchable core-in this case rubber cord-supports the structure, preventing damage from buckling. Existing helical electronics have only extended to stretchable interconnects between circuit modules, and individual components such as printed helical transistors. Fully stretchable circuits have, until now, only been produced in planar form: flat circuits, either using curved geometry to enable them to stretch, or using inherently stretchable elastomer substrates. Helical e-strips can bend along multiple axes, and repeatedly stretch between 30 and 50%, depending on core material and diameter. LED and temperature sensing helical e-strips are demonstrated, along with design rules for helical e-strip fabrication. Widely available materials and standard fabrication processes were prioritized to maximize scalability and accessibility.
Multimode polymer waveguides were created using epoxy resin materials. The fabrication process used non-contact photolithography, which is a simple and cost-effective method. During the experiments, ...a reliable and efficient developer was obtained. The samples were analyzed using scanning electron microscopy and the results showed that the ridge waveguides had a smooth surface and vertical sidewalls. The cross-section size was approximately 50 × 55 μm2. The waveguides had a transmission loss was about 0.08 dB/cm at a wavelength of 850 nm, which was measured using the cut-back method. Additionally, the waveguides were found to be stable in thermal and damp heat conditions.
•We present a developer for the production of epoxy resin optical waveguides in this paper.•We utilized a non-contact ultraviolet lithography method for the same.•We have also outlined a complete process for preparing the epoxy resin optical waveguide.•The performance of the sample was tested by conducting cut-back and aging tests.
In superconductor electronics fabrication processes developed at MIT Lincoln Laboratory, Josephson junctions (JJs) are placed near the top of the stack composed of nine or ten superconducting layers. ...We discuss the effects of this placement and other processing factors on uniformity of JJ critical current across 200-mm wafers; specifically, nonuniformity of residual stress in Nb films, wafer bow and warpage caused by accumulated stress in the underlying dielectric and superconducting layers, and effects of accumulated topography caused by patterning and planarization of wiring layers. We describe the typical fabrication defects, focusing primarily on the peculiar defects caused by electrochemical corrosion of dissimilar metals. To increase the integration scale and enhance fabrication capabilities, we are developing a new process, titled SC1, in which Nb/Al/AlO x /Nb JJs are placed near the bottom of the layer stack, preceded only by two planarized layers: resistor layer and superconducting ground plane. Six planarized Nb wiring layers are placed above the JJs. This layer stack should simplify routing of data and clock in integrated circuits, and allow for improvements in uniformity of small JJs. The SC1 process has a 250-nm minimum feature size for inductors, three sheet resistance options for resistors, and two options for JJ critical current density: 100 and 200 μA/μm 2 . We present fabrication details and process optimization aimed at improving JJ uniformity, increasing circuit yield, and reducing occurrence of corrosion defects to below the 1 ppm level.
In this paper, we report a graphene-based plasmonic photodetector optimized using the particle swarm optimization (PSO) algorithm and compatible with complementary metal–oxide–semiconductor (CMOS) ...technology. The proposed photodetector structure is designed to minimize fabrication challenges and reduce production costs compared to more complex alternatives. Graphene has been used for its unique properties in the detection region, titanium nitride (TiN) as a CMOS-compatible metal, and both to aid in plasmonic excitation. Photodetectors have key parameters influenced by multiple independent variables. However, practical constraints prevent thorough adjustment of all variables to achieve optimal parameter values, often resulting in analysis based on several simplified models. Here we optimize these variables by presenting a new approach in the field of photodetectors using the capabilities of the PSO algorithm. As a result, for the proposed device at the wavelength of 1550 nm, the voltage responsivity is 210.6215 V/W, the current responsivity is 3.7213 A/W, the ultra-compressed length is less than 3μm, and the specific detectivity is 2.566×107 Jones were obtained. Furthermore, the device in question works under the photothermoelectric effect (PTE) at zero bias and has zero dark current, which ultimately resulted in a very low noise equivalent power (NEP) of 4.5361 pW/Hz.
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