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In this paper, a novel fabrication technology of atomic force microscopy (AFM) probes integrating cantilever tips with an NV-rich diamond particle is presented. Nanomanipulation techniques combined with the focused electron beam-induced deposition (FEBID) procedure were applied to position the NV-rich diamond particle on an AFM cantilever tip. Ultrasonic treatment of nanodiamond suspension was applied to reduce the size of diamond particles for proper geometry and symmetry. The fabricated AFM probes were tested utilizing measurements of the electrical resistance at highly oriented pyrolytic graphite (HOPG) and compared with a standard AFM cantilever performance. The results showed novel perspectives arising from combining the functionalities of a scanning AFM with optically detected magnetic resonance (ODMR). In particular, it offers enhanced magnetometric sensitivity and the nanometric resolution.

Here we present an approach to measure the surface potential distribution of specimens using scanning tunnelling potentiometry with high potential gradients and relatively low sample bias. A special design of test structures containing pre-patterned electrodes was employed. Material of interest is transferred onto test structures, so that additional material processing during the investigations can be avoided. The utility of this solution is assessed in an investigation of high–strength metallurgical graphene. A maximum potential gradient of 49.2 V/mm was obtained by applying a sample bias of 0.8 V. Values of the resistivity of graphene inclusions up to 450 Ω·μm were observed. The influence of inclusions could be reduced by performing controllable post-transfer annealing. This could remove polymer residue from the graphene surface, but may introduce additional features in the Raman spectra. Work functions of 4.68–4.70 eV were estimated using Kelvin probe force microscopy.

Over 10 days of exposure in 0.05 M NaCl solution, Ni coating with mean crystallite size of 6 nm deposited in ChCl:EG deep eutectic solvent corrodes with diffusion constraints. Native oxide layer (4.7 nm thick) is a mixture of NiO and NiOOH. During exposure, NiO forms on the top of the layer of corrosion products, whose thickness exceeds 15 nm after 10 days. Double layer capacitance increases due to the growth of the active surface. Thickening of the layer and diffusion limitations leads to the increase in charge transfer resistance from teens of kΩ cm2 to 220 kΩ cm2.

Atomic force microscopy (AFM) belongs to the high resolution and high sensitivity surface imaging technologies. In this method force interactions between the tip and the surface are observed to characterize sample properties. In the so-called contact AFM (C AFM) mode the tip is brought into continuous contact with the sample. Significant progress in the AFM technology can be obtained, when the so-called active cantilever technology is implemented in the surface measurements. The built-in deflection actuator enables very precise excitation of the cantilever. Moreover, as the mass of the beam is very small the static beam displacement can be controlled in the wide frequency range. In the experiments, which we describe in this article, we applied the so called active electromagnetic cantilevers. They integrate a conductive loop which, when immersed in the magnetic field and biased with electric current, acts as an electromagnetic deflection actuator. The induced and precisely estimated Lorentz force, which is a function of bias current, cantilever geometry and magnetic field makes the cantilever deflect. Moreover, the probe stiffness can be calibrated with lower uncertainty as in the case of standard thermomechanical analysis. NZ AFM technology required application of a novel control algorithm, called PredPID, in which the cantilever bending caused by a proportional-integral-derivative (PID) block maintaining the constant load force was predicted.

PURPOSE The surface roughness of the dental restorations is significant to the denture plaque adhesion. METHODS In this work, we present the complex analysis of the electropolished CoCrW alloy remanium® star (Dentaurum, Germany) samples with laserengraved fiducial marks performed using complementary set of micro- and nanoscopic techniques: optical profilometry (OP), atomic force microscopy (AFM), scanning electron microscopy (SEM) and focused ion beam (FIB) milling. RESULTS Both mean and RMS roughness of the samples were reduced by electopolishing process, however, the results obtained using OP and AFM exhibited some discrepancies. This was caused by the relatively high local protruding defects developed on the processed surface. The cross-sections of the protrusions were made to analyze the cause of their formation as the EDS elemental content maps revealed that their composition was uniform. We also analyzed the local roughness in the smaller areas free from the defects. CONCLUSIONS In that case, both OP and AFM techniques delivered the same results. Analysis of results showed that various methods used for the surface roughness evaluation have to be used simultaneously to obtain complete and true analysis of the technological CoCrW samples.

Radiation pressure – RP phenomenon has drawn much interest since the beginning of the 20th century. There are many technologies linked with it and worth mentioning: cavity optomechanics with optical cooling and small forces amplification, single atom trapping, cantilevers spring constant calibration or high-power laser measurement. Nevertheless, the quantitative measurement of the RP is always influenced by many parasitic effects e.g. photothermal effects, which can appear while the beam is absorbed. The goal of the investigations presented in this paper was to design and manufacture a MEMS tool, the so-called RP cantilever, for the reliable interactions studies (i.e. due to radiation pressure) where the photothermal effect is highly reduced. Besides design and manufacturing process we present a set of experiments showing the properties of the proposed technology and its application possibilities.

In this paper, the fabrication process and electromechanical properties of novel atomic force microscopy probes utilising single-crystal boron-doped diamond are presented. The developed probes integrate scanning tips made of chemical vapour deposition-grown, freestanding diamond foil. The fabrication procedure was performed using nanomanipulation techniques combined with scanning electron microscopy and focused ion beam technologies. The mechanical properties of the cantilever were monitored by the measurement of thermally induced vibration of the cantilever after every fabrication step, allowing the mass changes in range of ng to be estimated. The endurance of the developed probes was tested during hundreds of topography measurements, which corresponds to a scanning length equal to 13.6 m, performed on a test sample in contact and lateral force microscopy modes. Analysis of the roughness parameters confirmed the extremely high wear resistance of the fabricated probes. The linear current voltage response on a highly-oriented pyrolytic graphite sample was recorded.

The goal of the conducted experiments was to evaluate if the increased density of the plasma in High Power Impulse Magnetron Sputtering (HiPIMS) argon discharge would give the possibility of obtaining diamond-like films with high sp3 fraction content at room temperature. The magnetron cathode was driven by the self-designed supply. It consisted of high voltage supply, tank capacitors and a set of switches. The tank capacitors and the inductances of connecting wires formed an LC resonant circuit. As a result, each sputtering pulse (duration of 20 μs, peak current of 1500–2200 A) was followed by the inverse pulse (duration of 25 μs, peak current of 400–700 A), both having a sinusoidal shape. The repetition time was 3 s. The silicon substrates were placed 8 cm above the target surface. The sputtering processes of 99.99% pure graphite target were conducted in argon atmosphere at a pressure of 6–8 × 10− 3 hPa. The carbon films obtained after 400 deposition pulses had a thickness of 35 nm. The surface RMS roughness, measured using an optical profiler, was about 2 nm. The refractive index was estimated by means of ellipsometric studies to be 2.45 and 2.3 at 400 and 800 nm, respectively. The sp3 hybridization fraction content of about 70–80% was calculated based on the analysis of Raman Scattering spectra.

This paper presents a comprehensive modeling and experimental verification of active piezoresistive atomic force microscopy (AFM) cantilevers, which are the technology enabling high-resolution and high-speed surface measurements. The mechanical structure of the cantilevers integrating Wheatstone piezoresistive was modified with the use of focused ion beam (FIB) technology in order to increase the deflection sensitivity with minimal influence on structure stiffness and its resonance frequency. The FIB procedure was conducted based on the finite element modeling (FEM) methods. In order to monitor the increase in deflection sensitivity, the active piezoresistive cantilever was deflected using an actuator integrated within, which ensures reliable and precise assessment of the sensor properties. The proposed procedure led to a 2.5 increase in the deflection sensitivity, which was compared with the results of the calibration routine and analytical calculations.

In this paper we present a metrological method for determination of mass density of focused ion beam induced deposition (FIBID) materials using quartz tuning fork (QTF) mass change sensors. Dimension and density determination of FIBID deposited nanostructures is necessary to develop and reliable and repeatable microfabribrication technology of the highest versatility. The proposed metrological methodology allows to determine mass change with 5 pg resolution and accuracy below 5 % if density is considered. The described method is suitable for precise FIBID precursor parameters determination conducted during the deposition as actuation and signal read-out of the applied QTF can be performed electrically. High accuracy, resolution and stability are ensured due to excellent properties of quartz forming the sensor structure.

The formation of dielectric composites on a target surface (target poisoning) reduces the deposition rate of a reactive magnetron deposition process in comparison to the deposition rate of metals. One way of minimizing this reduction is shifting the magnetron operating point from the dielectric to the transient mode. The goal of this paper is to show that a stable process of efficient aluminium oxide deposition can be carried out in a transient mode. An automated stabilizer driven by the electrical parameter of the magnetron power supply was used for process stabilization. The approach of process stabilization in the transient mode resulted in about seven times higher deposition rate of aluminium oxide than that of a standard dielectric mode and only two times lower than the deposition rate of aluminium. The optical properties of the thus obtained aluminium oxide films were studied by means of ellipsometric analysis. The model of film structure, consisting of stoichiometric aluminium oxide, metallic inclusions and voids, was proposed and dispersion characteristics were calculated. The complex refractive index characteristics were similar to those typical of aluminium oxide deposited during a standard pulsed reactive magnetron sputtering process.

“Photonic Crystals (PhC)” have been used in a variety of fields as a structure for improving the light extraction efficiency from materials with high index of refraction. In previous work we already showed the light extraction improvement of several PhC covered LYSO crystals in computer simulations and practical measurements. In this work, new samples are made using different materials and techniques which allows further efficiency improvements. For rapid prototyping of PhC patterns on scintillators we tested a new method using “Focused Ion Beam (FIB)” patterning. The FIB machine is a device similar to a “Scanning Electron Microscope (SEM)”, but it uses ions (mainly gallium) instead of electrons for the imaging of the samples’ surface. The additional feature of FIB devices is the option of surface patterning in nano-scale which was exploited for our samples. Three samples using FIB patterning have been produced. One of them is a direct patterning of the extraction face of a $0.8\times 0.8\times 10~\hbox{mm}^3$ LYSO crystal. The second and third were ${{\rm TiO}_2}$ coated LYSO crystal with a $1.4\times 1.4~\hbox{mm}^2$ out coupling face partly covered with high-quality photonic crystals. ${{\rm TiO}_2}$ has high refractive index (around 2.1 - 2.4)–which shows the best results in our light extraction simulations. In this paper, SEM images of the samples will be presented together with measurements of excited crystals which show unrivalled performance for such scintillator samples.

In this work we present combined Kelvin probe force microscopy and Raman spectroscopy studies of supported and suspended structures formed out of chemical vapor deposition (CVD) grown graphene. Work function of both suspended and supported graphene was -4.81 ± 0.06eV and -4.92 ± 0.06eV respectively. By G and 2D modes correlation we showed, that CVD graphene was influenced by biaxial strain. Increased contact potential difference (CPD) on the suspended graphene in comparison with the areas of the supported graphene was the sign of increased strain (from 0.05% to ~ 0.12%) rather than decreased doping (p-doping decreased from ~ 5.5 × 1012cm-2 to ~ 4.5 × 1012cm-2).

Van der Waals mono- and heterostructures have received great attention in recent years due to their new physics and electronic properties. Several novel device structures have been developed based on their properties, including tunnelling transistors, light emitting diodes and barristors. However, the construction of such structures usually involves transfer techniques which could induce damage and modify the electronic properties of the structures and degrade device performance. Here we show that a multi-step transfer process for graphene may disturb its transport properties at microscale. Bilayer graphene was transferred, using PMMA as supporting material, onto an Al2O3/Si substrate with pre-patterned chromium-palladium electrodes. Using scanning tunnelling potentiometry, we observed that the local potential gradient (and resulting current flow) significantly changed compared with the potential gradient arising from the electrodes’ position and biasing. This could be attributed to local material ad-layers, unspecified contact or additives present between sub-layers. This finding represents an important step in understanding the effect of transfer techniques on the quality of multilayer van der Waals mono- and heterostructures.

Laser-induced periodic surface structures (LIPSS) are highly periodic wavy surface features which are frequently smaller than incident light wavelength that bring possibility of nanostructuring of many materials. In this paper the possibility of using them to homogeneously structure the surface of artificial heart valve made of PyC was examined. By changing laser irradiation parameters such like energy density and pulse separation the most suitable conditions were established for 1030 nm wavelength. A wide spectrum of periodicities and geometries was obtained. Interesting side effects like creating a thin shell-like layer were observed. Modified surfaces were examined using EDX and Raman spectroscopy to determine change in elemental composition of surface.

Micro- and Electro-Mechanical Systems (MEMS) form a group of transducers used for very precise mass sensing (in the range of femtograms) and force detection (in the range of piconewtons) changes. These can be read by the resonant frequency shift or amplitude of mechanical vibration changes. Monitoring of optical path is one of the ways in which this detection can occur. The use of fibre construction makes the read-out system even more attractive. There are two popular types of Fibre Optics Displacement Sensors (FODS). The first – with amplitude of optical wave modulation – intensity sensors. The second – with phase modulation – fibre optics interferometers. In this paper Intensity Fibre Optic Displacement Sensor (I-FODS) for MEMS displacement metrology has been presented. A system formed by simple optical fibre optics, light source and photodetector had been tested and evaluated in order to obtain the highest possible sensitivity and resolution, using low-cost standard telecommunications equipment. The sensor׳s system is dedicated to MEMS amplitude of vibrations metrology and allows displacement monitoring in the range up to 400 μm with the resolution of 15 nm and the sensitivity of 0.19 V/nm for a mirror reflecting surface. The paper shows Quartz Tuning Fork (QTF) as an example of the MEMS with a very rough surface and its resonance frequency is equal to about 32 kHz. The designed I-FODS allows the QTF amplitude measurements with the resolution of 92 nm and the sensitivity of 0.017 mV/nm.

In this paper we present design and application of novel piezoresistive scanning thermal microscopy (SThM) probes. The proposed probe integrates a piezoresistive deflection sensor and thermally active, resistive nanosize tip. Manufacturing technology includes standard silicon MEMS/CMOS processing and sophisticated postprocessing using Focus Ion Beam milling. Authors also describe dedicated measurement technique in order to perform quantitative nanoscale thermal probing. Performance of the developed thermal probes is validated by test scans (topography and temperature distribution) of silicon nanoresistors supplied with current.

In this work the construction of experimental setup for MEMS/NEMS deflection measurements is presented. The system is based on intensity fibre optic detector for linear displacement sensing. Furthermore the electronic devices: current source for driving the light source and photodetector with wide-band preamplifier are presented.

In this work, we present the method of bending and stress measurements with electromagnetically actuated cantilever in sensors application. Proposed method compensate the bending of the cantilever induced under stress. Bending can be translated into surface stress difference which is a measure of intermolecular interactions. In proposed method Lorentz force is a balancing force to restore the cantilever to its original position. Additionally Lorentz force give us possibility do drive cantilever bidirectionally. The bending of cantilevers is measured using optical beam deflection (OBD) method and useful signal is derived from the feedback loop, that maintains the cantilever in a fixed position by balancing the deflecting force and the balancing force.

In the present paper, we describe a high sensitivity intensity fibre-optic displacement sensor with tens of picometre resolution combined with a sub-picometre resolution interferometric calibration system. Both integrated components form the so-called "2 in one ferrule" system 2iOF. The design and construction of the presented device depend on integrating two sensors' systems within one fibre-optic measuring head, which allows performing in situ calibration process with no additional time-consuming adjustment procedure. The resolution of the 2iOF system is 31 pm/Hz1/2 obtained with an interferometric Fabry-Perot based calibration system-providing accuracy better than tens of fm/Hz1/2 within 1 MHz bandwidth in the measurement range of up to 100 μm. The direct response from the intensity sensor is then the 2iOF output one. It is faster and more convenient to analyze in comparison, with much better resolution (3 orders of magnitude higher) but on the other hand also more time consuming and dependent on the absolute sample position interferometer. The proposed system is flexible and open to various applications. We will present the results of the piezoelectrical actuator displacement measurements, which were performed using the developed system.

Soft lithography and UV-NIL are important technologies for micro- and nano- structures replication [1]. It is possible to adapt surface structures preparation for many applications regarding e.g. opto-fluidic on-chip microscopy, wetting or reflection properties [2]. Light microscopy has been one of the most common tools in biological research, because of its high resolution and non-invasive nature of the light. Fresnel lens can be used in passive and active high quality polymer-based on-chip components for integrated photonics circuits [3]. In presented soft lithography technique the various materials were used for Fresnel lens replication: PDMS, h-PDMS and thiol-ene-epoxy resin. Mentioned polymers are characterized by high flexibility and transparency with minimal color. The silicon matrices replication process involves two main steps: anti-adhesive layer preparation and polymer deposition. The influence of structures geometry on the optical properties Fresnel lens has been investigated. The topography of obtained replicas was characterized using the atomic force microscopy (AFM) and scanning electron microscopy (SEM). The efficiency of light focus of the selected wavelength has been checked by intensity measurement using a standard optical microscope. As a result of replication 10□m diameter Fresnel lenses have been prepared.

Increased interest in micro-and nano-electromechanical systems (MEMS and NEMS) entail the development of reliable measurement techniques for the basic parameters of the designed and manufactured devices. The proposed methodology should provide high resolution, wide frequency range and the possibility to investigate both mechanical and electrical parameters during inspection process. In this article authors present methods for manufacturing of electrostatic MEMS devices. Measurement techniques will be presented for specifying parameters such as resonant frequency, quality factor and sensitivity of the previously manufactured structures. Manufacturing techniques will be presented on the example of the micropusher structure, whereas measurement techniques will be presented on the example of the microgripper structure.

In this paper the authors compare methods used for piezoresistive microcantilevers actuation for the atomic force microscopy (AFM) imaging in the dynamic shear force mode. The piezoresistive detection is an attractive technique comparing the optical beam detection of deflection. The principal advantage is that no external alignment of optical source and detector are needed. When the microcantilever is deflected, the stress is transferred into a change of resistivity of piezoresistors. The integration of piezoresistive read-out provides a promising solution in realizing a compact non-contact AFM. Resolution of piezoresistive read-out is limited by three main noise sources: Johnson, 1/f and thermomechanical noise. In the dynamic shear force mode measurement the method used for cantilever actuation will also affect the recorded noise in the piezoresistive detection circuit. This is the result of a crosstalk between an aluminium path (current loop used for actuation) and piezoresistors located near the base of the beam. In this paper authors described an elaborated in ITE (Institute of Electron Technology) technology of fabrication cantilevers with piezoresistive detection of deflection and compared efficiency of two methods used for cantilever actuation.

We report on the design, properties, and applications of a high-resolution and wide-bandwidth light intensity fiber optic displacement sensor for microelectromechanical system (MEMS) metrology. There are two types of structures that the system is dedicated to: vibrating with both high and low frequencies. In order to ensure high-frequency and high-resolution measurements, frequency down mixing and selective signal processing were applied. The obtained effective measuring bandwidth ranges from single hertz to 1 megahertz. The achieved resolution presented here is 116 pm/Hz1/2 and 138 pm/Hz1/2 for low-frequency and high-frequency operation modes, respectively, whereas the measurement of static displacement is 100 μm.

In this paper we present a method of fabrication and characterization of strain sensors fabricated with a focused electron beam induced deposition (FEBID) technology from Pt precursor. The FEBID structures were used as deflections sensors and applied to read-out resonance frequency of micromechanical bridges. In our experiments we have investigated silicon nitride structures with an integrated metallization path on which the FEBID strain sensors were deposited. In order to modify mechanical properties of the microbridge we developed and applied a focused ion beam (FIB) milling technology which allowed to modify the distribution of mechanical stress and consequently increase the deflection detection sensitivity. An atomic force microscopy (AFM) technology was applied to both characterize the electrical properties of the deposited structures and characterize properties of the fabricated devices. In this way the gauge factor (GF) of the FEBID fabricated nanogranular resistors (NGRs) of 4.25 was determined for the static microbridge deflection. Display Omitted The piezoresistive stress sensor on the silicon nitride microresonators were fabricated.The piezoresistive stress sensor were fabricated with focused electron beam induced deposition (FEBID) technology.We report a characterization procedures of microstructures using atomic force microscopy methods.