Customizable Fabrication Process for Flexible Carbon-Based Electrochemical Biosensors

In recent research, 3D printing has become a powerful technique and has been applied in the last few years to carbon-based materials. A new generation of 3D-printed electrodes, more affordable and easier to obtain due to rapid prototyping techniques, has emerged. We propose a customizable fabrication process for flexible (and rigid) carbon-based biosensors, from biosensor design to printable conductive inks. The electrochemical biosensors were obtained on a 50 µm Kapton® (polyimide) substrate and transferred to a 500 µm PDMS substrate, using a 3D-extrusion-based printing method. The main features of our fabrication process consist of short-time customization implementation, fast small-to-medium batch production, ease of electrochemical spectroscopy measurements, and very good resolution for an extrusion-based printing method (100 µm). The sensors were designed for future integration into a smart wound dressing for wound monitoring and other biomedical applications. We increased their sensibility with electro-deposited gold nanoparticles. To assess the biosensors' functionality, we performed surface functionalization with specific anti-N-protein antibodies for SARS-CoV 2 virus, with promising preliminary results.

Czochralski (CZ) process modification with cooling tube in the response to market Global silicon shortage

Recently, the silicon wafer producers, affected by Covid-19 and USA-China competition, looks for new production processes to increase the production. On the other hand, the common parts of CZ puller such as heater, crucible and thermal shield are optimized over time and now the common CZ process is reached to limitation for further improvement. Here, we propose a modified CZ method by adding a cooling tube into the growth zone. The new proposed Cz method is applied to the 8″ crystal growth process. A fully 3D transition model including energy equation, Navier–Stokes equation, surface-to-surface radiation heat transfer, moving mesh and thermal stress equations is implemented. The simulation is performed for both original and new CZ method. It was proved that the new CZ method increases the pulling speed up to 25 %. To ensure about the crystal quality, the thermal stress is compared between original and new proposed CZ method. Although it was found that the thermal stress increases about twice but still the maximum von Mises stress never exceeds the critical value 25 MPa. Additionally, the power consumption is also found to enhance maximum 2 kW under new conditions. To evaluate the model the interface and heater power for the original CZ puller is compared with industrial CZ process and it shows acceptable accuracy. © 2023 Elsevier B.V.

DUV-LED packaging using high density TSV in silicon cavity and laser-glass-frit-bonded UV transmitting glass cap

This paper reports an improved deep ultraviolet LED (DUV-LED) packaging based on Si Micro-Electro-Mechanical Systems (MEMS) process technology. The Si package (Si-PKG) consists of a cavity formed by Si crystalline anisotropic wet etching and through-silicon vias (TSVs) filled with electroplated Cu. The Si-PKG is hermetically sealed by laser local heating of screen-printed glass frit. This technology allows for the use of a DUV-transparent glass substrate, which has an unmatched coefficient of thermal expansion (CTE). Using a high-density array of TSV capped with AuSn solder bumps, the cooling performance of the DUV-LED has been greatly improved. And the contribution by the Si (111) side reflection of Si-PKG to the total light output was confirmed 13 %. As a result, an optical output of 114 % (50 mW) and a volumetric light power density of 380 % (14 mW/mm3) were recorded compared with the conventional AlN-packaged device. The developed compact low-cost Si-PKG is promising for wider applications of the DUV-LED including the disinfection of the new coronaviruses. © 2022 Elsevier B.V.

Inspiring Technologies for Digital Inclusivity

The article entitled Enhancing Moon Crescent Visibility using Contrast-Limited Adaptive Histogram Equalization and Bilateral Filtering Techniques has automated the determination of the religious festivals date based on the analysis of digital images. The authors have used underwater images that contain coral reef images as their case study. Since underwater images are usually suffering from distortion and light attenuation, an efficient edge detection technique is very important. The paper entitled Detection of Monocrystalline Silicon Wafer Defects using Deep Transfer Learning uses deep learning technique to detect defects in monocrystalline silicon wafer for industrial production.