Papers by Keyword: Microwire

Abstract: This paper illustrate a facile route to fabricate and develop zinc oxide microwire which acts as transducer for biosensor application. Pattern transfer process is conducted on the wafer substrate by using conventional photolithography process to form IDE electrode. The substrate is coated with positive photo-resist (PR) and exposed for UV light for 10 seconds. After development, the unexposed area is etched by using hydrochloric acid, HCI. In this study, zinc oxide material have become a remarkable choice for bio-sensing development due to large band gap and tailor for bio-molecular application. Zinc oxide solution was prepared through chemical route, that is by using sol-gel method. The coated ZnO films were annealed in furnace at 500°C for 2 hours. ZnO seed solution undergoes hydrothermal growth to synthesize ZnO microwires. ithThe substrate used for this study is p-type silicon wafer which is oxidized. SiO₂ layer is used because it acts as an insulator which is very essential for an electronic device to avoid electrical leakage and improve electron mobility. Further investigation of morphological and electrical characterization is conducted through SEM and I-V test .Average size diameter of Zno microwire is 0.45μm and exhibit 900μA of current at 5V.

Abstract: A simple design and simulation of microwire, contact pad and microfluidic channel on computer aided design (CAD) for chrome mask fabrication are described.The integration of microfluidic and nanotechnology for miniaturized lab-on-chip device has received a large research attention due to its undisputable and widespread biomedical applications. For the development of a micro-total analytical system, the integration of an appropriate fluid delivery system to a biosensing apparatus is required. In this study, we had presented the new Lab-On-Chip design for biomedical application. AutoCAD software was used to present the initial design/prototype of this Lab-On-Chip device. The microfluidic is design in such a way, that fluid flow was passively driven by capillary effect. Eventually, the prototype of the microfluidics was simulated using Comsol Multiphysics software for design validation.The complete design upon simulation is then used for mask fabrication. Hence, three mask is fabricated which consist of microwire, contact pad and microfluidics for device fabrication using photolithography process.

Abstract: In Micro/Nanowire fabrication, the alignment and exposure process are the most critical steps in photolithography process, and indeed for the whole biochip processing. This process determines the success of transferring the Micro/Nanowire design pattern on the mask to the photoresists on the wafer surface. Hence, the resolution requirementsand precise alignment are vital; each mask needs to be precisely aligned with original alignment mark in order to transfer the original pattern from mask onto photoresist layer. Otherwise, itcant successfully transfer the original pattern to the wafer surface causing device and circuit failure. Therefore, the UniMAPs Second Generation Mask Aligner is used for precise alignment and pattern transfer process. Thus, the paper present a preliminary study on fundamentals of resist exposure and development mechanisms for fabrication of Micro/Nanowire, We demonstrated significance of considering process parameters such as mask aligner, quality of resist, soft bake, exposure time and intensity, and development time. There was a very little room for alignment error; we were able to achieved error free design to the criticaldimension.

Abstract: Silicon microwires (MWs) previously synthesized using the VLS method with gold catalyst are being carburized at 1100°C under methane aiming to their conversion to SiC. SEM, TEM as well as XPS and Raman spectroscopy were used for structural and morphological characterization. After carburization achievement, SiC is found to be polycrystalline with a high density of stacking faults associated to an increase of surface roughness. Directions for the carburization process optimization are given.

Abstract: The solar cell concept presented here is based on 3C-SiC nano- or microwires and conju¬gated polymers. Therefore the silicon carbide wires are fabricated by a sol-gel route including a car-bothermal reduction step, allowing growth with predetermined uniform diameters between 0.1 and 2μm and lengths up to several centimetres. The design of our photovoltaic device is therein based on a p-i-n structure, well known e.g. from silicon photovoltaics, involving an intrinsic semiconduc¬tor as the central photoactive layer, sandwiched between two complementary doped wide-bandgap semiconductors giving the driving force for charge separation. In our case the 3C-SiC microwires act as the electron acceptor and simultaneously as carrier material for all involved components of the photovoltaic element.

Abstract: A novel excellent response of giant magnetoimpedance effect was found out in a magnetic LC-resonator consisting of a glass-coated amorphous Co83.2B3.3Si5.9Mn7.6 microwire and two capacitive cylindrical electrodes at the end of the microwire. The shapes of the impedance curves plotted vs. applied external dc-field varied dramatically with increasing frequency. The phase angle was also strongly found to be dependent on this field. The impedance curves were changing abruptly at near the resonance frequency. Because the permeability of ultra soft magnetic microwire is changing rapidly as a function of external magnetic field, the resonance frequency as well as impedance of the LC-resonator also changes drastically with respect to the external magnetic field. The maximum magnetoimpedance ratio value was reached as much as 1,600%. The sudden changes of phase angle as much as 180 degree evidenced the occurrence of resonance phenomenon. These results are promising for developing ultra-high sensitive magnetic sensor applications.

Abstract: Polyaniline(PANI) microwires and microspheres containing Au nanoparticles were prepared using different organic acid as dopant by an in-situ polymerization method. When L-CSA was used to synthesize PANI/Au composite, microwires were obtained. While by introducing hydrogen bonding and/or electrostatic interactions between mercaptocarboxylic acid capped Au nanoparticles and aniline molecules, microspheres were synthesized. SEM and TEM indicated that the diameter of the microwires was about 200 nm and the diameter of the microspheres was between 1 μm and 3 μm. FTIR and XRD characterized the structure of the PANI/Au composite microwires and microspheres.