Search results for "Lithography"
showing 10 items of 242 documents
A polarimetric sensor based on nanoporous free standing membranes
2012
A polarimetric sensor with state of the art sensitivity is developed using free standing porous silicon membranes. The use of an optimized etching receipt greatly reduces the pore roughness. Depolarization factors are thus limited and material birefringence is increased. Free standing membranes are fabricated in n-type substrates and characterized both from the optical and structural point of view. The proposed approach is fully CMOS compatible and can therefore pave the way to the development of cheap microarray that exploits multiplexing capabilities while keeping the amount of analyte required by the analysis down to the microliter level.
Recess photomask contact lithography and the fabrication of coupled silicon photonic and plasmonic waveguide switches
2015
Display Omitted A lithography technique capable of printing submicron-sized features inside deep cavities is presented.A so-called recess photomask adapted to the wafer's topography is employed.Based on a standard mask aligner, Recess Photomask Contact Lithography has moderate cost.Its efficiency for a photonic/plasmonic switch application was demonstrated experimentally.The technique is extensible to any design and to wafers with multiple level recesses. A novel lithographic method is presented, based on the use of a mask aligner in the contact mode with a modified photomask, the so-called recess photomask; its goal is the printing of submicron-sized patterns into deep cavities of a chip, …
Preparation of Ta-O-Based Tunnel Junctions to Obtain Artificial Synapses Based on Memristive Switching
2014
Magnetron sputtering and optical lithography are standard techniques to prepare magnetic tunnel junctions with lateral dimensions in the micrometer range. Here we present the materials and techniques to deposit the layer stacks, define the structures, and etch the devices. In the end, we obtain tunnel junction devices exhibiting memristive switching for potential use as artificial synapses.
Tunneling induced decomposition of Mo(CO)(6) onto TiO2(110) surface
2012
International audience; Tunneling induced decomposition of Mo(CO)(6) from the gas phase was studied on TiO2(110) surface by scanning tunneling microscopy (STM) and spectroscopy (STS). The efficiency of the procedure was followed by measuring the dot volume as a proportional indicator of the amount of the decomposed precursor. It was found that below 1 x 10(-5) Pa background pressure of Mo(CO)(6), there is no measurable effect and above 1 x 10(-4) Pa, the nanodot size is too large compared to the curvature of the tip (20-40 nm). A threshold bias of +3.1(+/- 0.1) V on the sample was measured for the decomposition of Mo(CO)(6) in gas ambient. In the absence of the precursor, dot formation was …
Single quantum dot emission at telecom wavelengths from metamorphic InAs/InGaAs nanostructures grown on GaAs substrates
2011
3 figuras, 3 páginas.
Innovative electronic lithography using self-assembly films in order to modify material surfaces at nanometric scale
2013
The concept of electon beam decomposition has been developed in order to create smaller patterns than those achieved by conventional lithographic methods. This work aimed to go further about this concept through a separation of the involved mechanisms in order to better understand them and thus reach a better control of process.A device was designed and a protocol was defined where the first stage is the adsorption at cryogenic temperature of metal-carbonyl compounds. The adsorbate is then decomposed by a focused electron beam and fragmentation residues are removed through annealing allowing the deposit reorganization. The study of the different steps of the elaboration method was followed …
Au-PVA Nanocomposite Negative Resist for One-Step Three-Dimensional e-Beam Lithography
2009
Au nanoparticles are synthesized in situ upon the electron beam exposure of a poly(vinyl alcohol) (PVA) thin film containing Au(III). The e-beam-irradiated areas are insoluble in water (negative-tone resist), and Au-PVA nanocomposite patterns with a variable profile along the structure can be thus generated (3D lithography) in a single step. A local characterization of the generated patterns is performed by high-resolution transmission electron microscopy and UV-vis localized surface plasmon resonance microspectroscopy. This characterization confirms the presence of crystalline nanoparticles and aggregates.
Nanoscale Deposition of Single-Molecule Magnets onto SiO2 Patterns
2007
bet on a silicon oxide template while the rest ofthe macroscopic surface remains free of molecules. Local oxi-dation was used to fabricate silicon oxide nanopatterns, eitherdots or stripes, over a Si (100) surface coated with a SAM.Their width ranged from 30 to 500 nm whereas the lengthcould be modified from a few nanometers up to several mi-crometers. Nanoscale direct assembly arose from a combina-tion of three factors: i) the strength of the attractive electro-static interactions between the molecules and the local oxides;ii) the weak repulsive interaction between the molecules andthe unpatternedsurface; and iii) the size of the nanopattern.Local oxidation nanolithography (LON) allows the…
An electrochemical route towards the fabrication of nanostructured semiconductor solar cells
2010
This work presents our preliminary results regarding an electrochemical process which allows the growth of nanostructured materials by means of nanopore templates. Also we analyze possible applications of this process to fabricate nanostructured semiconductors, such as CIGS, suitable for photovoltaic devices, and we consider the implications from the perspective of characterization techniques and device modelling when using such a technology.
Metallic Nanostructures Based on DNA Nanoshapes
2016
Metallic nanostructures have inspired extensive research over several decades, particularly within the field of nanoelectronics and increasingly in plasmonics. Due to the limitations of conventional lithography methods, the development of bottom-up fabricated metallic nanostructures has become more and more in demand. The remarkable development of DNA-based nanostructures has provided many successful methods and realizations for these needs, such as chemical DNA metallization via seeding or ionization, as well as DNA-guided lithography and casting of metallic nanoparticles by DNA molds. These methods offer high resolution, versatility and throughput and could enable the fabrication of arbit…