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Glass hot-embossing is one of essential techniques for the development of high-performance optical, bio, and chemical micro electromechanical system (MEMS) devices. This method is convenient, does not require routine access to clean rooms and photolithographic equipment, and can be used to produce multiple copies of a quartz mold as well as a MEMS component. In this study, quartz molds were prepared by hot-embossing with the glassy carbon (GC) masters, and they were applied to the hot-emboss of borosilicate glasses. The GC masters were prepared by dicing and focused ion beam (FIB) milling techniques. Additionally, the surfaces of the embossed quartz molds were coated with molybdenum barrier layers before embossing borosilicate glasses. As a result, micro-hot-embossed structures could be developed in borosilicate glasses with high fidelity by hot embossing with quartz molds.

In the present paper we consider two representative methods for residual stress evaluation at the micro-scale: a (semi-)destructive method involving material removal and the measurement of strain relief; and a non-destructive X-ray diffraction technique involving the use of micro-focused synchrotron X-ray beam. A recently developed strain relief approach is described using a Focused Ion Beam (FIB) to create a circular trench of progressively increasing depth around a circular "island". Residual stress is evaluated by the comparison of the strain relief (measured by digital correlation of displacements or strains) with Finite Element simulations. The technique is illustrated for a thin TiN coating layer. The second approach uses focused synchrotron X-ray beams for white beam Laue diffraction. Demonstration experiments described involve in situ loading of commercially pure nickel foil. Procedures for validation and improvement of accuracy are discussed.

Researches on the fabrication of ~ 0.1 × 0.1 μm² superconductor–insulator–superconductor (SIS) Josephson junctions are reviewed. Today, a typical dimension is 1–10 μm for Josephson junctions in superconducting integrated circuits. These Josephson junctions are defined by well-established photolithographic technology with reactive ion etching (RIE), and for the superconductor, Nb is almost always used. The merits of Nb include the facts that the superconducting transition temperature T_c of Nb (9.2 K) is higher than the boiling point of He (4.2 K), and that Nb has excellent stability against thermal cycling between room temperature and liquid-He temperature. For the fabrication of ~ 0.1 × 0.1 μm² junctions, on the other hand, there is a standard process with electron-beam lithography, shadow evaporation, and lift-off. This process works well for Al (T_c = 1.2 K), however, it is not ideal for Nb. The scope of this brief review is the nanoscale junction with Nb electrodes. We will look at the efforts of optimizing the standard lift-off process for Nb, electron-beam-lithographic versions of the Nb Josephson-junction technology, focused-ion-beam (FIB) etching as a convenient alternative to electron-beam lithography and RIE, etc. In order to characterize nanoscale tunnel junctions, the single-charge transistor has been often fabricated. Therefore, a summary of its theoretical transport properties is also included.

The capability of using Focused Ion Beam (FIB) for milling microchannels is experimentally and theoretically investigated. Microchannel structures are fabricated by a NanoFab 150 FIB machine, using an Arsenic (As²⁺) ion source. A beam current of 5 pA at 90 keV accelerating energy is used. Several microchannel patternings are milled at various dwell times at pixel spacing of 14.5 nm on top of a 60 nm gold-coated silicon wafer. An analytical/numerical model is developed to predict the FIB milling behavior. By comparing with the experimental measurements, the model predictions have been demonstrated to be reliable for guiding and controlling the milling processes.

Photonic crystals are the very promising novel materials for micro- and nanophotonics for visible region. To produce photonic crystals for this region of light, artificial structures with characteristic sizes less than 1 μm have to be manufactured. Electrochemical deep anodic etching and plasma etching techniques is normally used to produce such structures in silicon wafers. However, standard way of deep anodic etching realization is not suitable for sub-micrometer porous silicon formation. In the present work combination of the deep anodic etching and focused ion beam techniques is used to produce ordered structure of macropores in silicon.

To overcome the diffraction constraints of traditional optical lithography, the next generation lithographies (NGLs) will utilize any one or more of EUV (extreme ultraviolet), X-ray, electron or ion beam technologies to produce sub-100 nm features. Perhaps the most under-developed and under-rated is the utilization of ions for lithographic purposes. All three ion beam techniques, FIB (Focused Ion Beam), Proton Beam Writing (p-beam writing) and Ion Projection Lithography (IPL) have now breached the technologically difficult 100 nm barrier, and are now capable of fabricating structures at the nanoscale. FIB, p-beam writing and IPL have the flexibility and potential to become leading contenders as NGLs.

The three ion beam techniques have widely different attributes, and as such have their own strengths, niche areas and application areas. The physical principles underlying ion beam interactions with materials are described, together with a comparison with other lithographic techniques (electron beam writing and EUV/X-ray lithography). IPL follows the traditional lines of lithography, utilizing large area masks through which a pattern is replicated in resist material which can be used to modify the near-surface properties. In IPL, the complete absence of diffraction effects coupled with ability to tailor the depth of ion penetration to suit the resist thickness or the depth of modification are prime characteristics of this technique, as is the ability to pattern a large area in a single brief irradiation exposure without any wet processing steps. p-beam writing and FIB are direct write (maskless) processes, which for a long time have been considered too slow for mass production. However, these two techniques may have some distinct advantages when used in combination with nanoimprinting and pattern transfer. FIB can produce master stamps in any material, and p-beam writing is ideal for producing three-dimensional high-aspect ratio metallic stamps of precise geometry. The transfer of large scale patterns using nanoimprinting represents a technique of high potential for the mass production of a new generation of high area, high density, low dimensional structures. Finally a cross section of applications are chosen to demonstrate the potential of these new generation ion beam nanolithographies.

The cemented carbides containing various microstructures were machined by scanning a 30 keV Ga⁺ ion beam, with a nominal spot size of 300 nm and a current of 5300 pA, from side to side and up and down and a 100 μs pixel dwell time. In the coarse-grained cemented carbide, the surfaces of the WC phase parts were very smooth while those of the Co phase were rough. In the fine-grained cemented carbides, the surfaces were smoother on the whole and the irregularities were smaller compared with the coarse-grained cemented carbides. It is indicated that preparation of cemented carbide with finer WC grains, and decrease of the mean free path of Co phase are required for the FIB micro-machining to reduce surface irregularities.

Nanowires of Au and Cu were fabricated using a top–down method in which focused ion beam (FIB) milling process has been used. The width of the fabricated nanowires has been kept in the range of 45 to 300 nm and the length in the range of 2–10 μm. In situ electrical measurements of the nanowires were carried out. The resistivities of these wires are found to be higher (five to nine times larger than their bulk values). These results have been understood on the basis of increase in the electron surface scattering due to one-dimensional confinement of the electrons. Also, other effects such as nanogap formation in the range of 40 nm to few hundreds of nanometers, structural changes of the wires, increase of current density with time at constant applied voltage, etc. have been observed during measurements.

Strain rate is essential in study of the physics of fluids and solids undergoing deformation. State-of-art high strain rate tests have mainly been in macro-scale with an upper limit of $10^8{\mathrm{\text{s}}}^{-1}$. A graphene-based layered system is proposed to conduct nanometer-scale high strain rate testing. The process is investigated by molecular dynamics simulations. Accelerated single ion or group of ions are used to impact on the proposed system to generate ballistic or plate-like impact scenarios. The effects of impact energy, shape of impact absorber and the impaction location are investigated. The graphene layer is the key of the proposed system to spread the load and protect the sample. The results indicate that ion group and single ion impacts produce strain rates of $5.0$–$5.2\times 10^{11}{\mathrm{\text{s}}}^{-1}$ and $0.9$–$1.2\times 10^{11}{\mathrm{\text{s}}}^{-1}$, respectively. Ion group impact produces a more significant signal than single ion impact on the sensing nano-layer in the system. The ultimate strength of an Al-Cu alloy sample during ion impact is estimated to be 215MPa to 251MPa, significantly lower than predicted by the Johnson–Cook model because of the rapidly increased temperature and melting in the sample. The results demonstrate new possibilities for understanding high strain rate effects at nano-scale.

This research demonstrates the capability of controlled, focused ion beam (FIB)–assisted tailoring of morphologies in both multiwall carbon nanotubes (CNTs) and Y junction nonlinear CNT systems through defect engineering. We have shown that a 30 keV FIB Ga⁺ ion beam at low ion milling currents of 1 pA can be used to partially reduce the CNT diameter, to provide electrical conduction bottleneck morphologies for linear CNTs, and to introduce both additive and subractive defects at Y junction locations of Y-CNT samples. Our aim is for this work to provide motivation for additional research to determine the effects of ion-beam-induced changes in modulating the physical and chemical properties of nanotubes.

We present the effect of post-implantation annealing conditions on the structural and optical quality of InAs quantum dots (QDs) grown by combination of focused ion beam (FIB) and molecular beam epitaxy (MBE) approach. A FIB of Ga⁺ ion was employed to pattern a homogeneously GaAs buffer layers and then, an in situ annealing step followed by InAs deposition was performed. Three different post-implantation annealing conditions were tested and under well-optimized conditions, a dislocation and defect-free InAs QDs growth on FIB patterned surface was successfully achieved. Furthermore, using photoluminescence (PL) study, we demonstrate that our best sample shows almost similar optical quality as MBE grown QDs on unimplanted GaAs surface. The patterning technique described here can presumably be applied to systems other than InAs/GaAs and highly interesting for site-controlled nucleation of QDs that finds its potential applications in nanooptoelectronic devices.

The field emission tip arrays with sub-100 nm apices (nanoFEAs) on single crystal cerium hexaboride (CeB₆) surface were fabricated by the focused ion beam (FIB) milling microtechnology. The surface morphologies and field emissions of the nanoFEAs are systematically characterized. FIB milling, similar to the physical stripping process, can fabricate the nanoFEAs single crystal CeB₆ with uniform morphologies. The nanoFEAs with sharp tips of size about 50 nm demonstrate the lowest turn-on electric fields (2.0 V/$\mu$m), as well as a high current ($>$1 mA) at the field of 6.7 V/$\mu$m and a high stable emission current. Such excellent performances make CeB₆ nanoFEAs promising candidates for application in field emission electronics.

We present in situ and ex situ Laue micro-diffraction experiments on micron-sized single crystal pillars. We show that the focused ion beam technique introduces measurable damage in Si pillars. The dynamics of the Laue patterns of Au pillars demonstrate the occurrence of crystal rotation and strengthening is explained by plasticity starting on a slip system that is geometrically not predicted but selected because of the character of the pre-existing strain gradient.

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 295K, and exhibit the typical nonlinear I–V characteristics. The barrier height between Au electrode and nanorod is reduced from 0.137 to 0.088eV with increasing bias from 0.2 to 1V. The corresponding values of thermal activation energies are 0.172 and 0.06eV below the conduction band for 180–295 and 77.4–180K, respectively. This semiconductor-like behavior may result from the larger number of surface defects or localized states in the amorphorized PbTiO₃.

Glass hot-embossing is one of essential techniques for the development of high-performance optical, bio, and chemical micro electromechanical system (MEMS) devices. This method is convenient, does not require routine access to clean rooms and photolithographic equipment, and can be used to produce multiple copies of a quartz mold as well as a MEMS component. In this study, quartz molds were prepared by hot-embossing with the glassy carbon (GC) masters, and they were applied to the hot-emboss of borosilicate glasses. The GC masters were prepared by dicing and focused ion beam (FIB) milling techniques. Additionally, the surfaces of the embossed quartz molds were coated with molybdenum barrier layers before embossing borosilicate glasses. As a result, micro-hot-embossed structures could be developed in borosilicate glasses with high fidelity by hot embossing with quartz molds.