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Metal oxide semiconductor (MOS) gas sensors are widely used for gas detection. Typically, the hotplate element is the key component in MOS gas sensors which provide a proper and tunable operation temperature. However, the low power efficiency of the standard hotplates greatly limits the portable application of MOS gas sensors. The miniaturization of the hotplate geometry is one of the most effective methods used to reduce its power consumption. In this work, a new method is presented, combining electron beam lithography (EBL) and focused ion beam (FIB) technologies to obtain low power consumption. EBL is used to define the low-resolution section of the electrode, and FIB technology is utilized to pattern the high-resolution part. Different Au++ ion fluences in FIBs are tested in different milling strategies. The resulting devices are characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and secondary ion mass spectrometry (SIMS). Furthermore, the electrical resistance of the hotplate is measured at different voltages, and the operational temperature is calculated based on the Pt temperature coefficient of resistance value. In addition, the thermal heater and electrical stability is studied at different temperatures for 110 h. Finally, the implementation of the fabricated hotplate in ZnO gas sensors is investigated using ethanol at 250 °C. [ABSTRACT FROM AUTHOR]

The present work focuses on the shrinkage of PMMA films under irradiation and its application to the creation of optical devices. We prepared the free-standing PMMA films in four different thicknesses (13, 21, 32, and 43 μm), and PMMA films of the same thickness, but deposited on a glass substrate. A diffraction grating was chosen as the optical device to show the applicability of the method. The study revealed that at a film thickness of 13–32 μm, the shrinkage of the free-standing film increases proportionally to its thickness, while the film on the substrate does not have a pronounced dependence. Films with the thickness of 43 µm do not follow this trend. It was found that under the same irradiation conditions, the film on the substrate shrinks more compared to the free-standing film. Interference patterns from the created diffraction gratings were shown to present spurious illumination areas. [ABSTRACT FROM AUTHOR]

Metal oxide semiconductor (MOS) gas sensors are widely used for gas detection. Typically, the hotplate element is the key component in MOS gas sensors which provide a proper and tunable operation temperature. However, the low power efficiency of the standard hotplates greatly limits the portable application of MOS gas sensors. The miniaturization of the hotplate geometry is one of the most effective methods used to reduce its power consumption. In this work, a new method is presented, combining electron beam lithography (EBL) and focused ion beam (FIB) technologies to obtain low power consumption. EBL is used to define the low-resolution section of the electrode, and FIB technology is utilized to pattern the high-resolution part. Different Au++ ion fluences in FIBs are tested in different milling strategies. The resulting devices are characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and secondary ion mass spectrometry (SIMS). Furthermore, the electrical resistance of the hotplate is measured at different voltages, and the operational temperature is calculated based on the Pt temperature coefficient of resistance value. In addition, the thermal heater and electrical stability is studied at different temperatures for 110 h. Finally, the implementation of the fabricated hotplate in ZnO gas sensors is investigated using ethanol at 250 °C.

The most significant goal of nanophotonics is the development of high-speed quantum emitting devices operating at ambient temperature. In this regard, plasmonic nanoparticles-on-mirror are potential candidates for designing high-speed photon sources. We introduce a novel hybrid nanoantenna (HNA) with CdSe/CdS colloidal quantum dots (QDs) based on a silver nanocube in a metal cup that presents a nanoparticle-in-cavity coupled with an emitters system. We use focused ion beam nanolithography to fabricate an ordered array of cups, which were then filled with colloidal nanoparticles using the most simple drop-casting and spin coating methods. The spectral and time-resolved studies of the samples with one or more nanocubes in the cup reveal a significant change in the radiation characteristics of QDs inside the nanoantenna. The Purcell effect causes an increase in the fluorescence decay rate (≥30) and an increase in the fluorescence intensity (≥3) of emitters in the HNA. Using the finite element method simulations, we have discovered that the proximity of the cups wall affects the oscillation modes of the gap plasmon, which, in turn, leads to changes in the electric field enhancement inside the nanoantenna gap. Additionally, substantial variations in the behavior of the gap plasmons at different polarizations of the exciting radiation have been revealed. The proposed nanoantenna can be useful in the development of plasmonic sensors, display pixels, and single-photon sources. [ABSTRACT FROM AUTHOR]

Optical and electrooptical properties of a system consisting of subwavelength metal gratings and nematic liquid crystal layer are studied. Aluminium gratings that also act as interdigitated electrodes are produced by focused ion beam lithography. It is found that a liquid crystal layer strongly influences both the resonance and light polarization properties characteristic of the gratings. Enhanced transmittance is observed not only for the TM-polarized light in the near infrared spectral range but also for the TE-polarized light in the visible range. Although the electrodes are separated by nanosized slits, and the electric field is strongly localized near the surface, a pronounced electrooptical effect is registered. The effect is explained in terms of local reorientation of liquid crystal molecules at the grating surface and propagation of the orientational deformation from the surface into the bulk of the liquid crystal layer. [ABSTRACT FROM AUTHOR]

The feature of the promising tool of lithographic nanostructuring based on selective exposure of polymer resist by ion beam is very compact (of about tens of nanometers) beam interaction volume. Herewith the main part of beam energy is deposited in the resist and is spent to its modification. It causes the set of advantages specific for this method: sub-10 nanometer resolution achievable, very high energy efficiency and almost complete absence of proximity effect. But also due to this feature absorbed doze essentially inhomogeneous in resist and the dissolution rate is strongly dependent on depth. So the common procedure of resist contrast determination cannot be applied anymore. In the present work a new method for resist contrast determination considering the relation between dissolution rate and deposited energy density is suggested and realized. By using it for PMMA resist irradiated by 30 keV Ga+ ion beam the value of contrast was determined to be 3.1 and ions energy length was estimated to be 42 nm. [ABSTRACT FROM AUTHOR]

3D microstructures in pure poly(dimethylsiloxane) (PDMS) and PDMS with embedded Au nanoparticles were prepared by ion beam lithography without any further etching. Two mega‐electron volts helium and 10 MeV oxygen ions were used for ion microstructuring. Parallel lines of 1 mm in length and 10 μm in thickness were fabricated for investigation of the effect of the nanoparticles presence in the polymer on the surface morphology of the created microstructures. The created microstructures were checked by optical microscope. Infrared (IR) spectrometry was used to study the effect of the ions type and fluence on the chemical changes of the material. Atomic force microscopy was used for the fine detail study as well as for checking the microstructure quality. Analysis revealed an increased radiation resistance of the nanocomposite compared to the pure PDMS. Shrinkage is proportional to the fluence, but the maximum value for both materials is limited by saturation. 3D microstructure in modified PDMS obtained at the same irradiation condition as pure PDMS is characterized by its smaller height. Obtaining the microstructure in nanocomposite of the same height as in pure PDMS by increasing the fluence can be impossible due to saturation of shrinkage and/or radiation‐induced heating of the material. [ABSTRACT FROM AUTHOR]

PbTiO3 nanorods with tetragonal phase were synthesized by hydrothermal method and heat treatment, and temperature-dependent electrical transport properties of individual PbTiO3 nanorod were investigated. The results show that the conductivities of PbTiO3 nanorods are gradually enhanced with temperature increasing from 77.4 to 295 K, and exhibit the typical nonlinear I–V characteristics. The barrier height between Au electrode and nanorod is reduced from 0.137 to 0.088 eV with increasing bias from 0.2 to 1 V. The corresponding values of thermal activation energies are 0.172 and 0.06 eV below the conduction band for 180–295 and 77.4–180 K, respectively. This semiconductor-like behavior may result from the larger number of surface defects or localized states in the amorphorized PbTiO3. [ABSTRACT FROM AUTHOR]

A new approach for calculating the ion dose spatial distribution of the focused ion beam is proposed. The approach is based on the analysis of the secondary electron microscopy image of the area irradiated by the focused ion beam. [ABSTRACT FROM AUTHOR]

The work presents experimental data of Ga+ focused ion beam etching of disc and ring patterns in Si3N4/GaN structure. The reasons for the difference in etching depth between the discs and the rings are described. [ABSTRACT FROM AUTHOR]

The detection of quantal exocytic events from neurons and neuroendocrine cells is a challenging task in neuroscience. One of the most promising platforms for the development of a new generation of biosensors is diamond, due to its biocompatibility, transparency and chemical inertness. Moreover, the electrical properties of diamond can be turned from a perfect insulator into a conductive material (resistivity ~mΩ·cm) by exploiting the metastable nature of this allotropic form of carbon. A 16‑channels MEA (Multi Electrode Array) suitable for cell culture growing has been fabricated by means of ion implantation. A focused 1.2 MeV He+ beam was scanned on a IIa single-crystal diamond sample (4.5 × 4.5 × 0.5 mm3) to cause highly damaged sub-superficial structures that were defined with micrometric spatial resolution. After implantation, the sample was annealed. This process provides the conversion of the sub-superficial highly damaged regions to a graphitic phase embedded in a highly insulating diamond matrix. Thanks to a three-dimensional masking technique, the endpoints of the sub-superficial channels emerge in contact with the sample surface, therefore being available as sensing electrodes. Cyclic voltammetry and amperometry measurements of solutions with increasing concentrations of adrenaline were performed to characterize the biosensor sensitivity. The reported results demonstrate that this new type of biosensor is suitable for in vitro detection of catecholamine release.

Large arrays of permalloy (Ni81Fe19) annular structures were fabricated using a self-aligned patterning process based on ion-beam proximity lithography (IBPL), where a broad beam of energetic He ions is shaped into billions of ion beamlet by a stencil mask to pattern electron beam sensitive resist. IBPL was used to form an array of circular openings in poly(methyl methacrylate) (PMMA) resist, followed by a tone reversal process to form circular pillars in an underlying polymethylglutarimide (PMGI) layer. The PMGI pillars were conformally coated with silicon oxide, which was followed by anisotropic reactive ion etch (RIE) to form silicon oxide rings, which were transferred into the underlying sputter deposited permalloy thin film by ion milling. This fabrication approach was used to make 6 x 6 mm2 arrays of rings on a constant pitch of 670 nm with the outer diameters varied between 350 nm and 450 nm with a fixed inner diameter of 150 nm. Three unique samples that were fabricated and characterized using a vibrating sample magnetometer. The measured M-H loops showed the switching from an onion to a vortex and back to an onion state and are in good agreement with micromagnetic simulations and previously published data. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, 3D volumetric energy deposition and local crosslinking of hydrogen silsesquioxane (HSQ) are experimentally and numerically explored in focused helium ion beam lithography (HIBL). In particular, a through‐membrane exposure method is developed to make visible and subsequently to measure the 3D interaction volume and energy deposition of helium ions in HSQ. By comparing the actual dimensions of the crosslinked HSQ structures with Monte Carlo modeling of the spatial distribution of the energy deposition, the critical energy density for crosslinking HSQ is obtained. Finally, 3D nanofabrication of complex crosslinked HSQ nanostructures such as embedded nanochannels and suspended grids is demonstrated using two different exposure configurations. The proposed method expands the 2D point spread function of HIBL into three dimensions, thus opening a new avenue for nanoscale 3D fabrication. [ABSTRACT FROM AUTHOR]

Electron Beam Lithography (EBL) at sub-10 nm resolution is mainly limited by resist contrast and proximity effects. In this work, we investigate the use of a recently developed alumina-based resist as a negative-tone resist for EBL at 100 keV and focused helium ion beam lithography (FHIBL). The resist is synthesized using a sol-gel method and turns into a near completely inorganic alumina system when exposed to the electron/ion beam. We first investigate the effect on the resist contrast curve on i) development temperature; ii) stability of the resist after exposure and before post-baking and development; and iii) aging of the resist solution. We demonstrate the patterning of isolated features as small as 6.5 nm using an EBL and 5 nm using FHIBL and a resolution down to 10 nm for FHIB exposed films. Finally, we demonstrate the pattern transfer of 10 nm lines with an aspect ratio of 10 in silicon, using an optimized reactive ion etching process. [ABSTRACT FROM AUTHOR]

High-resolution focused ion beam lithography has been used to fabricate YBa2Cu3O7-x (YBCO) wires with nanometric lateral dimensions. In the present work, we investigate Flux-flow instabilities in nanowires of different widths, showing sudden voltage switching jumps from the superconducting to the normal state. We present an extensive study on the temperature and field dependence of the switching characteristics which reveal that voltage jumps become less abrupt as the temperature increases, and disappear at the vortex-liquid state. On the contrary, the current distribution at the critical point becomes narrower at high temperatures. Sharp voltage switchings very close to the critical current density can be obtained by reducing the width of the nanowires, making them very appealing for practical applications. [ABSTRACT FROM AUTHOR]

Recently, carbon ion beam based therapies are becoming important in the medical field including dosimetric applications. The present study focuses on the synthesis, and dosimetric characteristics of CaSO 4 :Dy nanophosphors (NPs) irradiated by 200 keV C ions. This NPs was prepared by chemical co-precipitation method , irradiated at different fluences of low energy C ion and characterized for the structural, morphological and thermoluminescence (TL) properties. X-Ray Diffraction of the NPs revealed that the hkl peak intensities, as well as crystalline sizes, decreased with increasing ion fluences. Transmission Electron Microscopy results showed that the particle surface found to be damaged due to ion irradiation. From Fourier Transform Infra-Red spectra, the wave numbers ranging from 2000 cm −1 to 2450 cm −1 and 800 cm −1 to 1800 cm −1 have drastically changed in terms of intensity, the shape, and several bonds were observed to be broken and merge due to the C ion induced effects. Moreover, the surface morphology also shows systematic changes. This CaSO 4 :Dy NPs was found to be a quite sensitive to TL dosimetric properties in the fluence range of 1 × 10 13 to 5 × 10 14 ions/cm 2 . The TL properties such as glow curve, sensitivity response, fading, and trapping parameters have been calculated. The patterns that emerge suggest that different trapping mechanisms are operating as evident from their glow curve deconvolution (GCD) functions. The CaSO 4 :Dy NPs can be effectively used to detect the dose of 200 keV C ions during therapy as a medical dosimetry or vivo dosimetry. [ABSTRACT FROM AUTHOR]

Coherently embedded structures in a crystalline substrate are known as endotaxial structures. In this paper, we report on the growth of silver (Ag) endotaxial structures in silicon using the aspects of both ion implantation and irradiation. In one case, endotaxial nanostructures of Ag at the Si interface are formed with 30 keV negatively charged silver ions (Ag − ) on GeO x /SiO x /Si system. In another case, 30 keV Ag − ions are used to create defects in GeO x , SiO x and in silicon substrate. Further deposition of a thin layer of Ag on irradiated GeO x /SiO x /Si system yielded endotaxial Ag nanostructures relatively at lower temperature (700 °C) compared to the system without any irradiation effects. We also reveal that the irradiation effects with 1.8 MeV Ag + ions do not influence the early onset temperature of endotaxial nanostructure formation (unlike low energy ions). We show that it is essential to have crystalline silicon substrate to form Ag endotaxial nanostructures to grow endotaxial structures. [ABSTRACT FROM AUTHOR]

Minimal proximity effect coupled with uniform energy deposition in thin polymer layers make Proton Beam Writing (PBW) an intuitive direct-write lithographic technique. Feature sizes matching the focused beam spot size have been fabricated in photoresists down to 19 nm. Reproducible sub-10 nm beam focusing will make PBW a promising contender for sub-10 nm lithography. In this paper, we present beam size characterization by imaging a PBW resolution standard using transmitted/scattered ions and secondary electrons. Using Scanning Transmission Ion Microscopy (STIM) spectra for 1 and 2 MeV H 2 + beams, we experimentally measure the thickness of the resolution standard to be 0.9 ± 0.1 μm, applying two independent calibration methods, which match the original intended thickness during fabrication. Through bias optimization of a Micro-Channel Plate (MCP), we show a tuneable secondary electron detection per proton for imaging with a maximum of 75% e/p for a beam of 1 MeV H 2 + . Based on STIM mode beam size measurement, we discuss considerations for quadrupole system alignment in order to remove higher order translational and rotational misalignments critical to achieve sub-40 nm spot sizes. A spot size of 13 × 32 nm 2 (STIM) was achieved using a newly developed interface, capable of autofocusing ion beams and performing PBW. [ABSTRACT FROM AUTHOR]

In the present work, we report on the monolithic fabrication by means of ion beam lithography of hollow micro-channels within a diamond substrate, to be employed for microfluidic applications. The fabrication strategy takes advantage of ion beam induced damage to convert diamond into graphite, which is characterized by a higher reactivity to oxidative etching with respect to the chemically inert pristine structure. This phase transition occurs in sub-superficial layers thanks to the peculiar damage profile of MeV ions, which mostly damage the target material at their end of range. The structures were obtained by irradiating commercial CVD diamond samples with a micrometric collimated C + ion beam at three different energies (4 MeV, 3.5 MeV and 3 MeV) at a total fluence of 2 × 10 16 cm −2 . The chosen multiple-energy implantation strategy allows to obtain a thick box-like highly damaged region ranging from 1.6 μm to 2.1 μm below the sample surface. High-temperature annealing was performed to both promote the graphitization of the ion-induced amorphous layer and to recover the pristine crystalline structure in the cap layer. Finally, the graphite was removed by ozone etching, obtaining monolithic microfluidic structures. These prototypal microfluidic devices were tested injecting aqueous solutions and the evidence of the passage of fluids through the channels was confirmed by confocal fluorescent microscopy. [ABSTRACT FROM AUTHOR]

The concept of fluorescent sensing in a microchannel equipped with focusing light Fresnel lenses has been demonstrated. The concept employs a line or array of Fresnel lenses generating a line or array of focused light spots within a microfluidic channel, to increase the sensitivity of fluorescent signal detection in the system. We have presented efficient methods of master mold fabrication based on the lithography method and focused ion beam milling. The flexible microchannel was fabricated by an imprint process with new thiolene-epoxy resin with a good ability to replicate even submicron-size features. For final imprinted lenses, the measured background to peak signal level shows more than nine times the increase in brightness at the center of the focal spot for the green part of the spectrum (532 nm). The effectiveness of the microlenses in fluorescent-marked Escherichia coli bacteria was confirmed in a basic fluoroscope experiment, showing the increase of the sensitivity of the detection by the order of magnitude. [ABSTRACT FROM AUTHOR]

Focused ion beam nanoscale synthesis has emerged as a critical tool for selected area nanofabrication. Helium and neon ion beams from the gas field ion source have recently demonstrated unparalleled resolution among other scanning ion beams. In this review, the authors focus on the nanoscale synthesis applications for these ion species which have been demonstrated to date. The applications and recent work can broadly be grouped into the following categories: (1) Monte Carlo simulations, (2) direct-write milling or sputtering, (3) ion beam lithography, (4) selective ion implantation or defect introduction and (5) gas-assisted processing. A special emphasis is given toward using He+ and Ne+ for the processing of two dimensional materials, as several groups have demonstrated promising results. Finally, the authors will discuss the future outlook of He+ and Ne+ nanoprocessing techniques and applications. [ABSTRACT FROM AUTHOR]

Overlay alignment is a concern for nanolithography applications, in particular, for those using step and repeat techniques targeting next-generation lithographic applications. In this context, a new method and a proof of concept (POC) setup for accurately aligning a mask with a semiconductor wafer is presented. Utilizing active scanning probe technology, the method is employable for various lithographic techniques such as photolithography, electron- and ion-beam lithography, nanoimprint lithography (NIL). The developed method is demonstrated in the example of NIL. It employs compact highly integrated atomic force microscopes (mini-AFM), which are fixed on the lithographic template. The mini-AFM systems are applied for imaging of the surface relief marks on the semiconductor wafer to carry out the alignment process. In a next step, the obtained AFM section images are used to calculate the deviations and steer the bottom stage carrying the processed wafer in order to achieve the desired positioning accuracy. A POC test setup was built for emulation of the alignment procedure. Several measurement studies are addressed to evaluate the applicability of the overlay alignment method. As a result, it is shown that the implemented test setup is able to determine the positioning error of the bottom stage carrying the wafer with an accuracy of around 10 nm (without temperature compensation). [ABSTRACT FROM AUTHOR]

A technique for forming a nanosized gate of a high-power microwave transistor is proposed. The optimal exposure parameters of 950-PMMA-A2 and ELP-20 resists are established. The technological route of ion beam lithography with the use of multilayer resists is investigated. A technique for fabricating a continuous mesh of earthed alignment marks formed on the ion-sensitive resist to visualize the alignment marks on a dielectric substrate by ion microscopy is developed. [ABSTRACT FROM AUTHOR]

Studies of pattern formation on variable-temperature Ge targets by ion beam sputtering are presented. A high-energy heavy polyatomic bismuth ion beam was used to reveal the effect of thermal spikes in the dynamics of pattern formation. By varying the target temperature in the range from 123 to 773 K, different morphologies of the irradiated surfaces were obtained. A smooth surface was observed for a target temperature of 123 K. Sputtering at a target temperature between 300 and 573K gave rise to poorly oriented dot patterns and resulted in a checkerboard pattern at a target temperature of 773 K. Mechanisms of surface patterning under ion irradiation are discussed. [ABSTRACT FROM AUTHOR]

The authors present a simulation-based methodology for reconstructing the focused ion beam current density profile using sputtering and implantation information available from transmission electron microscopy images of single beam-width lines created using a Gaþ beam on SiO2 substrate. A bi-Gaussian distribution for the ion beam was assumed. Ga+ implantation in fused silica substrate was iteratively simulated sweeping through beams of varying parameters using SRIM MONTE CARLO software. The resulting lateral distribution and density of the implanted Ga were visualized and compared to the experimental implanted Ga distribution on the cross-section of a physically sputtered line. Beam simulation parameters resulting in a close match between simulated and experimental Ga+ implantation were accepted as describing the primary ion beam. The authors apply the current density distribution of reconstructed beam profile to analyze single beam-width line profiles etched with XeF2 precursor and deposited with W(CO)6 precursor. Results indicate that XeF2 gas assisted etching and W(CO)6 deposition processes were enhanced in the peripheral regions of the Ga+ ion beam which are characterized by low current densities on the order of 1.0 x 10-4 pA=nm2. A similar simulation methodology as presented here can presumably be applied to reconstruct beam current density profiles and applied to characterize gas-assisted processes for arbitrary combinations of primary ion species and gaseous precursors with suitable substrates. This methodology is directly applicable to development of industrial processes using focused ion beams for modification of semiconductor, microelectromechanical systems, microfluidic, and photonics devices. [ABSTRACT FROM AUTHOR]

This work utilizes short time heat treatments of submicrometer-thickness NiTi alloy films fabricated using biased target ion beam deposition and investigates crystallization. Films were fabricated on Si substrates, and thicknesses were about 150 nm, which were much less than conventional thicknesses on the order of micrometers. To understand the composition dependence, Ni concentrations were varied such that alloys ranged from Ti-rich to near-equiatomic. Rapid thermal annealing was used for the heat treatment and temperatures ranged from 465 up to 540 °C for 10 min. X-ray diffraction measurements for each of the NiTi alloy compositions revealed that the crystallization temperature was equivalent (~490 °C) and the B2 austenitic atomic crystal structure existed. Evolutions of surface morphologies, measured using atomic force microscopy, as a function of heat treatment temperature confirmed the composition independence of the crystallization temperature. To investigate the structure using transmission electron microscopy, 150nm-thickness films were also deposited on ultrathin SiN substrates and heat treated, which confirmed equiaxed grains existed. Crystallization and annealing heat treatments for nanoscale films can be carried out for time on the order of minutes, which should curtail detrimental diffusion effects known to compromise shape memory behavior. [ABSTRACT FROM AUTHOR]

A novel method for fast and flexible fin field effect transistor (FinFET) prototyping using a Ga+ focused ion beam is presented. The fin width and height control is explored, aiming for the successful fabrication of prototypes. This method results in fins with negligible Ga incorporation, when compared to traditional focused ion beam milling techniques. Our method for multiple fin FinFET prototyping enables advanced device fabrication and great flexibility regarding both the number of fins and fin width. Working FinFET prototypes have been fabricated using the proposed fin definition method, and the electrical characterization is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Our study describes FIB technological aspects of preparing mask for GaN selective area epitaxy on Si3N4/GaN template. [ABSTRACT FROM AUTHOR]

The investigation of secondary effects induced by ionizing radiation represents a new and ever-growing research field in radiobiology. This new paradigm cannot be investigated only using standard instrumentation and methodologies, but rather requires novel technologies to achieve significant progress. In this framework, we developed diamond-based sensors that allow simultaneous real-time measurements with a high spatial resolution of the secretory activity of a network of cells cultured on the device, as well as of the dose at which they are exposed during irradiation experiments. The devices were functionally characterized by testing both the above-mentioned detection schemes, namely: amperometric measurements of neurotransmitter release from excitable cells (such as dopamine or adrenaline) and dosimetric evaluation using different ionizing particles (alpha particle and X-ray photons). Finally, the sensors were employed to investigate the effects induced by X-rays on the exocytotic activity of PC12 neuroendocrine cells by monitoring the modulation of the dopamine release in real-time. [Display omitted] [ABSTRACT FROM AUTHOR]

ABSTRACT To obtain a successful outcome after rotator cuff repair, the repaired tendon must be biologically anchored to the bone. However, the histological structure at the repaired tendon-bone interface differs from that of the site of normal tendon insertion. Therefore, analyzing postnatal development in detail will contribute to understanding the repaired tendon-bone interface after rotator cuff repair. In this study, we analyzed postnatal development at the tendon-bone insertion in terms of temporal changes in SOX9/SCX expression and three-dimensional (3D) ultrastructure with FIB/SEM tomography, a new scanning electron microscopic method. Sixteen postnatal Sprague-Dawley rats were used for the study. One-, two-, three-, and four-week-old rats were sacrificed and both right and left shoulders were removed; eight normal supraspinatus tendon insertions were isolated for each time point. At each time point, four specimens were evaluated with fluorescent immunostaining for SOX9/SCX expression, and the remaining four specimens were evaluated with FIB/SEM tomography. Even in postnatal development, SOX9+/SCX+ expression was observed at the tendon insertion; expression gradually decreased with postnatal development at the normal tendon insertion. In 3D ultrastructure, the morphology of the cells and the number/orientation of the cell processes drastically changed by postnatal week 4. The pattern of SOX9/SCX expression and 3D ultrastructural changes obtained in this study contribute to an understanding of the complicated development of normal tendon-bone insertion. Therefore, this study helps elucidate the pathophysiology of tendon-bone insertion, especially in cases of rotator cuff tear and repair. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:969-976, 2016. [ABSTRACT FROM AUTHOR]

Helium ion beam lithography (HIBL) is an emerging technique that uses a sub-nanometre focused beam of helium ions generated in the helium ion microscope to expose resist. It benefits from high resolution, high sensitivity and a low proximity effect. Here we present an investigation into HIBL on a novel, negative tone fullerene-derivative molecular resist. Analysis of large area exposures reveals a sensitivity of ~ 40 μC/cm 2 with a 30 keV helium beam which is almost three orders of magnitude higher than the sensitivity of this resist to a 30 keV electron beam. Sparse line features with line widths of 7.3 nm are achieved on the ~ 10 nm thick resist. The fabrication of 8.5 half-pitched lines with good feature separation and 6 nm half-pitched lines with inferior but still resolvable separation is also shown in this study. Thus, sub-10 nm patterning with small proximity effect is demonstrated using HIBL using standard processing conditions, establishing its potential as an alternative to EBL for rapid prototyping of beyond CMOS devices. [ABSTRACT FROM AUTHOR]

Due to their outstanding mechanical properties, diamond and diamond-like materials find significant technological applications ranging from well-established industrial fields (cutting tools, coatings, etc.) to more advanced mechanical devices as micro- and nano-electromechanical systems. The use of energetic ions is a powerful and versatile tool to fabricate three-dimensional micro-mechanical structures. In this context, it is of paramount importance to have an accurate knowledge of the effects of ion-induced structural damage on the mechanical properties of this material, primarily to predict potential undesired side-effects of the ion implantation process, and possibly to tailor the desired mechanical properties of the fabricated devices. We present an Atomic Force Microscopy (AFM) characterization of free-standing cantilevers in single-crystal diamond obtained by a FIB-assisted lift-off technique, which allows the determination of the Young's modulus of the diamond crystal after the MeV ion irradiation process concurrent to the fabrication of the microstructures, and subsequent thermal annealing. The AFM measurements were performed with the beam-bending technique and show that the thermal annealing process allows for an effective recovery of the mechanical properties of the pristine crystal. [ABSTRACT FROM AUTHOR]