Search results for " AFM"

Tantalum nitride thin film resistors by low temperature reactive sputtering for plastic electronics

2008

This article describes the fabrication and characterisation of tantalum nitride (TaN) thin film for applications in plastic electronics. Thin films of comparable thickness (50-60 nm) have been deposited by RF-magnetron-reactive sputtering at low temperature (100 °C) and their structure and physical (electrical and mechanical) properties have been correlated by using sheet resistance, stress measurements, atomic force microscopy (AFM), XPS, and SIMS. Different film compositions have been obtained by varying the argon to nitrogen flow ratio in the sputtering chamber. XPS showed that 5:1, 2:1 and 1:1 Ar:N 2 ratios gives Ta 2 N, TaN and Ta 3 N 5 phases, respectively. Sheet resistance revealed a…

Influence of pH and temperature on the early stage of mica alteration

2012

Mineral dissolution and precipitation reactions actively participate in controlling fluid chemistry during water–rock interaction. In this study, the changes in the biotite and muscovite basal surface nano-morphology were evaluated during interaction with fluids of different pH (pH = 1.1, 3.3 and 5.7) at different temperatures (T =2 5, 120, and 200 C). Results show that at the nanometre scale resolution of the atomic force microscope (AFM), dissolution generates etch pits with a stair-shaped pattern over the (0 0 1) surface. The flux of dissolved elements decreases when pH increases. However, at pH 5.7, a change was found in the flux after 42 h of reaction when abundant gibbsite and kaolini…

Raman Monitoring of Strain Induced Effects in Mechanically Deposited Single Layer Graphene

2012

Graphene is a two dimensional building block for carbon allotropes of many other dimensionality and shows remarkable electronic and optical properties that attract enormous interest. In order to make graphene useful for real technology, a control of its electronic and mechanical properties is a must. In this respect, a crucial step for the use of graphene layers in device fabrication is the deposition onto suitable substrates, understanding the interaction with them. Micromechanical cleavage of graphite has been used to produce high-quality graphene sheets. The aim of this work is to study the strain effects induced in graphene by the deposition process using Raman spectroscopy and scanning…

Streptomyces coelicolor extracellular vesicles

This study may reveal the importance of extracellular vesicles in the physiology of S. coelicolor and may also have important biotechnological implications.

Fibronectin-bound α5β1 integrins sense load and signal to reinforce adhesion in less than a second

2017

Integrin-mediated mechanosensing of the extracellular environment allows cells to control adhesion and signalling. Whether cells sense and respond to force immediately upon ligand-binding is unknown. Here, we report that during adhesion initiation, fibroblasts respond to mechanical load by strengthening integrin-mediated adhesion to fibronectin (FN) in a biphasic manner. In the first phase, which depends on talin and kindlin as well as on the actin nucleators Arp2/3 and mDia, FN-engaged α5β1 integrins activate focal adhesion kinase (FAK) and c-Src in less than 0.5 s to steeply strengthen α5β1- and αV-class integrin-mediated adhesion. When the mechanical load exceeds a certain threshold, fib…

Rapid and eco-friendly synthesis of graphene oxide-silica nanohybrids

2014

Mucin MUC1: a key protein in oral physiology and the molecular mechanisms of sensory perception of astringency

2022

(E)-2-cyano-3-(5'-piperidin-1-yl-2,2'-bithien-5-yl)acrylic acid: a new fluorescent probe for detecting prefibrillar oligomers

2013

Influence of a Thiolate Chemical Layer on GaAs (100) Biofunctionalization: An Original Approach Coupling Atomic Force Microscopy and Mass Spectrometr…

2013

International audience; Widely used in microelectronics and optoelectronics; Gallium Arsenide (GaAs) is a III-V crystal with several interesting properties for microsystem and biosensor applications. Among these; its piezoelectric properties and the ability to directly biofunctionalize the bare surface, offer an opportunity to combine a highly sensitive transducer with a specific bio-interface; which are the two essential parts of a biosensor. To optimize the biorecognition part; it is necessary to control protein coverage and the binding affinity of the protein layer on the GaAs surface. In this paper; we investigate the potential of a specific chemical interface composed of thiolate molec…