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Search for "photoresist" in Full Text gives 63 result(s) in Beilstein Journal of Nanotechnology.
Evaluation of replicas manufactured in a 3D-printed nanoimprint unit
Beilstein J. Nanotechnol. 2018, 9, 1573–1581, doi:10.3762/bjnano.9.149
- of a solvent were found to be superior for most nanoimprint applications. A large dispersion of the samples was found. Keywords: nanoimprint; oriented gradient; photoresist; polymer; replica; Introduction Although the basic principles behind nanoimprint lithography (NIL) have been known for many
- to qualify any material as appropriate; therefore a larger than usual number of samples (more than 100) were prepared. Both, thermally curable and UV-curable materials have been tested: Ormostamp®, NOA81, SU8 photoresist, Microposit S1818 photoresist, and poly(methyl methacrylate) (PMMA). Ormostamp
- nm. At the first glance, NOA81 is not conceived as a polymer for nanoimprint replication, yet the absence of solvent makes it a good candidate for replicating. SU8 2001: Epoxy-based negative photoresist from MicroChem. It must be spin-coated on a substrate. It employs solvent that must be removed in
Optical near-field mapping of plasmonic nanostructures prepared by nanosphere lithography
Beilstein J. Nanotechnol. 2018, 9, 1536–1543, doi:10.3762/bjnano.9.144
- induced surface deformation at the hot spots upon laser illumination. The localization of the hot spots is then indirectly revealed in the subsequent AFM scanning of the surface [26]. Similarly, Murazawa et al. [30] spin-coated a pattern of gold nanorods with a photoresist before irradiating the sample
The nanofluidic confinement apparatus: studying confinement-dependent nanoparticle behavior and diffusion
Beilstein J. Nanotechnol. 2018, 9, 301–310, doi:10.3762/bjnano.9.30
- stability for several hours. Cover glass and sample preparation The mesa of the cover glass (D263T borosilicate, UQG) was fabricated as follows: First, a masking layer of 30 nm Cr and 300 nm Au was sputtered onto the glass. Second, a photoresist (AZ4533, MicroChemicals) was spin coated and patterned by
Refractive index sensing and surface-enhanced Raman spectroscopy using silver–gold layered bimetallic plasmonic crystals
Beilstein J. Nanotechnol. 2017, 8, 2492–2503, doi:10.3762/bjnano.8.249
- nanoimprint lithography The PCs were fabricated using soft nanoimprint lithography as previously reported [22][23][24][25][26][37][38]. In brief, a composite hard-PDMS/soft-PDMS mixture was cast on a patterned photoresist master with arrays of nanohole relief structures in order to fabricate the PCs. A glass
Synthesis of coaxial nanotubes of polyaniline and poly(hydroxyethyl methacrylate) by oxidative/initiated chemical vapor deposition
Beilstein J. Nanotechnol. 2017, 8, 872–882, doi:10.3762/bjnano.8.89
- -beam evaporation, conventional lithography with a shadow mask was used to create a pattern for the electrodes. The photoresist AZ 5214 E (Merck GmbH), the developer AZ 726 (MIF) (Merck GmbH) and deionized water (stopper) were used for the lithography. After the e-beam evaporation, samples were annealed
Relationships between chemical structure, mechanical properties and materials processing in nanopatterned organosilicate fins
Beilstein J. Nanotechnol. 2017, 8, 863–871, doi:10.3762/bjnano.8.88
- /erosion rate of the photoresist and hardmask layers utilized to define and transfer the desired pattern into the nanoporous organosilicate [35]. As we will show, feature-size dependences also manifest as variations of composition and mechanical properties within the resulting nanoporous organosilicate
Surface improvement of organic photoresists using a near-field-dependent etching method
Beilstein J. Nanotechnol. 2017, 8, 784–788, doi:10.3762/bjnano.8.81
- , which are beyond the absorption edge of the photoresist (310 nm), we compare the resulting cross-sectional etching volumes. The volumes were larger when 325 nm light was employed, i.e., closer to the absorption edge. Although 405 nm light did not cause structural change in the photoresist, a higher
- reduction of the surface roughness was observed as compared to the 325 nm light. These results indicate that even wavelengths above 325 nm can cause surface roughness improvements without notably changing the structure of the photoresist. Keywords: near-field etching; organic photoresists; surface
- single-photon absorption but the former has a much lower probability [14][15]. The photoresist in this study is a conventional, organic, chemically amplified resist (CAR) (EPIC 2096 ArF Photoresist), which is sensitive to ArF excimer laser excitation (λ = 193 nm). Organic photoresists are easily obtained
Silicon microgrooves for contact guidance of human aortic endothelial cells
Beilstein J. Nanotechnol. 2017, 8, 675–681, doi:10.3762/bjnano.8.72
- alkaline etch. A thin layer of positive photoresist AZ 1505 (MicroChemicals) was deposited by spin-coating on the silicon wafer at 500 rpm for 10 s then 5000 rpm for 30 s, following by baking at 100 °C for 30 s. Then the wafer was patterned by direct-write lithography (DWL 66FS, Heidelberg Instruments Gmbh
- ). After developing the photoresist by immersing the wafer in the metal ion free developer AZ 726 (MicroChemicals) for 45 s, the lithographic pattern is transferred onto the oxide layer by etching the silicon in buffered hydrofluoric acid. The photoresist film is no longer needed and therefore removed with
Anodization-based process for the fabrication of all niobium nitride Josephson junction structures
Beilstein J. Nanotechnol. 2017, 8, 539–546, doi:10.3762/bjnano.8.58
- vacuum conditions. Temperature control is particularly relevant when lithographic patterns impressed by photoresist (an organic polymeric compound melting above 120 °C) are present on the substrate because the degassing of the polymer pollutes the deposition chamber. For this reason the temperature of
- another concentration of N2. Because the high temperature induced on the substrate softens the photoresist and pollutes the NbN films. In Figure 4 the section of the 3D-plot of Figure 3 corresponding to a dc power of 200 W is shown. We can see more clearly that a N2 flux of 9 sccm gives NbN film with a Tc
- . These techniques rely on three layers of NbN/AlN/NbN, and require, as a first step in the fabrication process the use of a photoresist-patterned substrate. This condition, in turn, limits the highest acceptable dc power to 200 W. For a reduced sputtering power, the plasma composition must be redefined
Copper atomic-scale transistors
Beilstein J. Nanotechnol. 2017, 8, 530–538, doi:10.3762/bjnano.8.57
- thickness of 3 nm/40 nm deposited on a silicon wafer covered with a thermal oxide layer (300 nm) using e-beam evaporation. The gap between the source and the drain is 2 μm, and the distance from the gate to the source is approximately 147 μm. The electrolyte channel developed in an SU-8 photoresist film is
- using direct laser writing and reactive ion etching techniques (Method 2 described in the Experimental section). The window with a diameter of 3 mm and height of 0.05 mm was fabricated in the SU-8 photoresist. In order to observe fabrication and operation of the copper transistor in situ, a ceramic
- insulating layer were prepared with a direct laser writer (Heidelberg Instruments DWL 66). The microelectrodes covered with an SU-8 film on a silicon wafer with a thin thermally oxidized SiO2 film (300 nm) were fabricated step by step as follows. A photoresist (AZ 5214E) was spin-coated on the wafer. With a
When the going gets rough – studying the effect of surface roughness on the adhesive abilities of tree frogs
Beilstein J. Nanotechnol. 2016, 7, 2116–2131, doi:10.3762/bjnano.7.201
- involves laying down a layer of SU-8 photoresist, then applying a mask to remove specific areas of resistance, and then etching the exposed areas to give the desired patterns. The moulds were negatives of the PDMS patterned surfaces, which produced surfaces consisting of round dimples having fixed
Precise in situ etch depth control of multilayered III−V semiconductor samples with reflectance anisotropy spectroscopy (RAS) equipment
Beilstein J. Nanotechnol. 2016, 7, 1783–1793, doi:10.3762/bjnano.7.171
- piece of the sample of type A. The etch process was stopped right after reaching the second GaAs layer (A3) (see red line in Figure 2a). The photoresist etch mask was removed before cleaving the sample. As can been seen RAS control of dry-etching enables the RIE operator to stop the etch process at a
- mask of photoresist has been used to define the stripes (laser ridges). Adjacent to each of the ridges the upper cladding, the active region, and the lower cladding are removed by dry-etching to achieve strong optical confinement (compare [35]). In a second lithographic process (process II, see Figure
- 5b) and etch step the laser ridge itself is being structured to alter the effective refractive index locally and thus to achieve a film waveguide lens in part of the ridge. Therefore, again a photoresist mask is used to define the desired pattern on the laser ridge in combination with RIE. (The shape
Active and fast charge-state switching of single NV centres in diamond by in-plane Al-Schottky junctions
Beilstein J. Nanotechnol. 2016, 7, 1727–1735, doi:10.3762/bjnano.7.165
- defined conductive channel between the Al and Au contacts, the channel region including the contacts were protected with a photoresist and then the whole diamond surface surrounding the channel area were O-terminated via exposition to oxygen plasma. After lift-off process of the photoresist, the
Nano- and microstructured materials for in vitro studies of the physiology of vascular cells
Beilstein J. Nanotechnol. 2016, 7, 1620–1641, doi:10.3762/bjnano.7.155
- experiments in cell biology for the last two decades [53][54]. Photolithography uses light, a photomask and a photosensitive material (photoresist) to create a pattern in the micrometer (or sub-micrometer) range (Figure 4B). The thickness of the layer of photoresist will determine the height of the structures
- advantage of optical superresolution, with which it is possible to go below the light diffraction limit, to perform photolithography with nanometer resolution. For example, using nano-antennas it was possible, by two-photon polymerization, to produce photoresist nanodots with diameters below 30 nm [64]. In
- a different work, a plasmon was used to pattern a photoresist layer by means of NSOM (near-field scanning optical microscopy). A lateral resolution of about 50 nm was achieved, with a fabrication speed of ca 10 mm/s [65]. Nanoimprint lithography (NIL) is a low-cost nanopatterning technique for 2D
Dealloying of gold–copper alloy nanowires: From hillocks to ring-shaped nanopores
Beilstein J. Nanotechnol. 2016, 7, 1361–1367, doi:10.3762/bjnano.7.127
- of metal nanowires (Figure 1a). We show how controlling accurately the growth of such defects can be of real benefit for engineering the surface of nanowires. At first, a photoresist film is deposited by spin coating on a silicon substrate and then patterned using laser interference lithography
- (Figure 1a); the process is described in details elsewhere [21]. Then, the silicon is etched through the photoresist mask using SF6/O2 plasma to create nanograted silicon structures (Figure 1a(2)). After this step, an oxygen plasma treatment is applied to partially etch the photoresist lines and transform
- them into residues (Figure 1a(3)). The existence of photoresist residues is related to the non-homogenous etching of the polymers forming the photoresist. In the last stage, the metal is deposited by magnetron sputtering over the prepared substrate to form an array of nanowires containing hillocks
NO gas sensing at room temperature using single titanium oxide nanodot sensors created by atomic force microscopy nanolithography
Beilstein J. Nanotechnol. 2016, 7, 1044–1051, doi:10.3762/bjnano.7.97
- fabrication of a single titanium oxide ND gas sensor. (a) PMMA spin-coated and AFM nanomachining, (b) Ti deposition, (c) PMMA lift-off, (d) photoresist spin-coated, (e) exposure and development, (f) Au deposition, (g) photoresist lift-off, and (h) AFM nano-oxidation. (Adapted from [32]). (a,b) AFM topographic
Dielectrophoresis of gold nanoparticles conjugated to DNA origami structures
Beilstein J. Nanotechnol. 2016, 7, 948–956, doi:10.3762/bjnano.7.87
- photomask was placed and the construct exposed for 2.5 min to UV light (365 nm). For the development of the photoresist, the glass slides were incubated for 30–60 s into a developer solution (AR 500-47, Allresist; 1:2 dilution in ddH2O). An adhesion layer of 3 nm chrome and 30 nm gold was thermally
- evaporated and finally the photoresist was removed with the remover solution AR 300-72 (Allresist) by sonication. Dielectrophoretic manipulation of the 6HBs The gold pads were cleaned by immersing them stepwise for 20 s into 100% fuming nitric acid (Merck) and 1 min into a neutralization solution [hydrogen
Thermo-voltage measurements of atomic contacts at low temperature
Beilstein J. Nanotechnol. 2016, 7, 767–775, doi:10.3762/bjnano.7.68
- length. A drawback of using this (thermally and) electronically insulating substrate was the necessity to overcome the charge-caused deterioration of the electron-beam during the lithography process. To do so, substrates were covered by a thin 10 nm Al film on top of the standard photoresist (MAA/PMMA
In situ SU-8 silver nanocomposites
Beilstein J. Nanotechnol. 2015, 6, 1661–1665, doi:10.3762/bjnano.6.168
- applications. However, device fabrication of such materials always encounters the challenge of incorporation of preformed nanoparticles into photoresist materials. As a solution to this problem, an easy new method of fabricating silver nanocomposites by an in situ reduction of precursors within the epoxy-based
- photoresist SU-8 has been developed. AgNO3 dissolved in acetonitrile and mixed with the epoxy-based photoresist SU-8 forms silver nanoparticles primarily during the pre- and post-exposure soft bake steps at 95 °C. A further high-temperature treatment at 300 °C resulted in the formation of densely
- homogeneously distributed silver nanoparticles in the photoresist matrix. No particle growth or agglomeration of nanoparticles is observed at this point. The reported new in situ silver nanocomposite materials can be spin coated as homogeneous thin films and structured by using UV lithography. A resolution of 5
Hollow plasmonic antennas for broadband SERS spectroscopy
Beilstein J. Nanotechnol. 2015, 6, 492–498, doi:10.3762/bjnano.6.50
- with a current of 40 pA at a dose of 5 pC/μm2. The interaction between gallium ions and the photoresist produces high secondary electrons doses, which cause the inversion of a thin layer of resist around the milled hole. When the sample is immersed in acetone, unexposed resist is dissolved while the
Electrical contacts to individual SWCNTs: A review
Beilstein J. Nanotechnol. 2014, 5, 2202–2215, doi:10.3762/bjnano.5.229
- novolac-based photoresist to prevent SWCNTs from directly contacting the photoresist. However, the relatively high on-resistance (250 ± 100 kΩ) indicates the necessity for further optimization. Recently, the authors [71] have investigated an approach by using a thin layer of alumina to protect the SWCNTs
Advances in NO2 sensing with individual single-walled carbon nanotube transistors
Beilstein J. Nanotechnol. 2014, 5, 2179–2191, doi:10.3762/bjnano.5.227
- nanotubes, photoresist and other processing residues, interfaces with the substrate and tube-metal junctions. Their role in carrier transport and their response to analyte exposure can be diverse and difficult to reproduce. To circumvent this difficulty, empirical or phenomenological models are typically
Effect of channel length on the electrical response of carbon nanotube field-effect transistors to deoxyribonucleic acid hybridization
Beilstein J. Nanotechnol. 2014, 5, 2081–2091, doi:10.3762/bjnano.5.217
- , namely: (i) short channels (L = 6 µm), (ii) long channels (L = 300 µm), and (iii) ultra-long channels (L = 1500 µm). To obtain the short channel FETs, source–drain electrodes were patterned onto the substrates containing SWCNTs using standard photolithography (AZ7220, positive photoresist) at 25 ºC
- substrates containing the CVD-grown SWCNTs. The 1 µm thick SiO2 acted as the dielectric gate. Selective photoresist capping using photolithography was applied to cover the CNT–metal junction which resulted in devices with only the channel exposed. Only devices with a single CNT as a channel were considered
Growth and structural discrimination of cortical neurons on randomly oriented and vertically aligned dense carbon nanotube networks
Beilstein J. Nanotechnol. 2014, 5, 1575–1579, doi:10.3762/bjnano.5.169
- guidance systems for cells. General scheme for the fabrication of spatially deposited CNT islands. (a) A photoresist is lithographically structured; b) defined aluminium and iron layers were evaporated onto the substrate. After removing the photoresist the catalyst islands of bimetallic Al/Fe are spatially
Organic and inorganic–organic thin film structures by molecular layer deposition: A review
Beilstein J. Nanotechnol. 2014, 5, 1104–1136, doi:10.3762/bjnano.5.123
- demonstrated that when treated with acid, the backbone of the formed film reacted from the acid-labile groups. When exposed to basic solution, the polymer films were stable. These experiments proved that MLD can be utilized to fabricate photoresist materials. To make the film a photoresist material, a
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