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It was found that the results of magnetic force microscope (MFM) imaging weredifferent with the probe scanning directions, and the images were often distorted. Thispaper studied the effect of scanning directions on the MFM imaging, and a method forthe distortion compensation was proposed to reduce the errors. In the study, threedifferent scanning directions with the angles of 0°, 45° and 90°, were used to measurethe magnetic force distribution of a magnetic sample with a regular structure. Thetheoretical and experimental results have shown that the scanning direction parallel tothe magnetic structure will cause a minimum phase shift difference and lead to a structure distortion. With the proposed compensation method, the distortion structureswere corrected and the effect of scanning directions on the MFM imaging wassignificantly reduced. This work provides a way to obtain the correct images ofmagnetic structures using an MFM and to improve the imaging quality in a wide range of MFM applications.

This paper presents a new maskless laser nanoscale manufacturing technology to fabricate micro and nano structured surfaces with specific functionalities. Cross-scale fabrication of micro and nano structures on biomaterials (such as metal, alloy and polyethylene) with wear resistant properties. Investigation of conditions and process parameters for cross-scale fabrication of micro and nano structures with specific functionalities (wear resistant properties) for the target applications in biomedicine.

Nanoassembly is a new field that deals with the controlled manipulation, handling and assembly of atoms, molecules and nano objects by robots for manufacturing of nano structures, devices and systems. Nanoassembly is expected to have revolutionary applications in almost all the scientific and technological areas. This paper presents a general review of nanoassembly considering its current developments and application. It discusses several method of nanoassembly technology and in detail self-assembly, object-oriented nanoassembly and hybrid nanoassembly.

In this study, an AFM tip was used to penetrate the human colon cancer cells (SW480) in the culture medium containing pEGFP-N1-TRAIL plasmids. The trail plasmids encoded with the enhanced green fluorescent protein (EGFP) were moved into the SW480 cells through membrane holes created by the AFM probe. Following the penetration, the culture medium was changed into the RPMI1640 medium supplemented with 10% of fetal bovine serum and incubated for 24h. The expression of PEGFP-N1-TRAIL in SW480 cells was then observed by inverted fluorescence microscope. The experiment results indicate that the AFM tip can be used to penetrate the membranes of targeted cells individually.

The division-of-focal-plane (DoFP) polarizer is used to capture polarization information in real time without rotating the polarizer. In this paper, different periods of aluminum nano-wire grids with four different orientations offset by 45° were fabricated using electron beam lithography (EBL) and inductively coupled plasma-reactive ion etching (ICP-RIE). The pitch of each unit was 7.4 μm in a standard square. The transmission intensity measurements of DoFP arrays with different periods were performed to obtain the extinction ratios and transmission ratios which were used to evaluate the performance of grid polarizers.

Nanoindentation technology has proven an effective method to investigate the viscoelastic properties of biological cells. The experimental data obtained by nanoindentation are frequently interpreted by Hertz contact model. However, in order to facilitate the application of Hertz contact model, a mass of studies assume cells have infinite thickness which does not necessarily represent the real situation. In this study, a rigorous contact model based upon linear elasticity is developed for the interpretation of indentation tests of flattened cells which represent a factual morphology. The cell, normally bonded to the petri dish, is initially treated as an elastic layer of finite thickness perfectly fixed to a rigid substrate, and the conic indenter is assumed to be frictionless. The theory of linear elasticity is utilized to solve this contact issue and then the solutions are extended to viscoelastic situation which is regarded as a good indicator for mechanical properties of biological cells. To test the present model, an AFM-based creep test has been conducted on living human hepatocellular carcinoma cell (SMMC-7721 cell) and its fullerenol-treated counterpart. The results indicate that the present model could not only describe very well the creep behavior of SMMC-7721 cells, but can also curb overestimation of the mechanical properties due to substrate effect. Moreover, the present model could identify the difference between the control and treated SMMC-7721 cells in terms of the extracted viscoelastic parameters, suggesting its potential in revealing the biomechanical effects of fullerenol-like drug treatment on cancerous cells.

This paper presents a method for the manipulation of magnetic nanoparticles by optically induced dielectrophoresis (ODEP) device that can realize the transportation and convergence of nanoparticles. ODEP can be realized with a sandwich structure of three layers including the photoconductive layer, the liquid layer with the sample and the indium tin oxide electrode (ITO) layer. In this work, magnetic nanoparticles with the diameter of 10–100nm were successfully manipulated by positive dielectrophoresis force. The solution with magnetic nanoparticles on a mica substrate placed in the sandwich structure was dried in the air and imaged by atomic force microscope (AFM). The AFM images showed that the magnetic nanoparticles were converged in the illumination area. This method can be used to manipulate magnetic nanoparticles.

A method for the surface texturing of well-designed and high controllable micro dimple structures on stainless steel by direct laser interference lithography (DLIL) is presented. The method offers its innovation that the micro circular dimple structures can be fabricated directly by controlling the process of three-beam laser interference. Different exposure durations have been studied to achieve the optimum value of the dimple diameter and density in order to reduce the friction coefficient of stainless steel. The dry sliding test of friction coefficients were performed by mechanical tester (UMT-TriboLab) under normal loads of 15 N. The results indicate that the micro circular dimple structures with the average dimple diameter of 4.2 μm and density of 23 percent have about 77% reduction of friction coefficient compared with untreated surfaces.

All the five independent elastic properties/constants of micro- and nano-structured hierarchical and self-similar random irregular honeycombs with different degrees of cell regularity are obtained by analysis and computer simulation in this paper. Cell wall bending, stretching, and transverse shearing are the main deformation mechanisms of hierarchical honeycombs. The strain gradient effects at the micro-meter scale, and the surface elasticity and initial stress effects at the nano-meter scale are incorporated into all the deformation mechanisms in the analysis and finite element simulations. The results show that the elastic properties of hierarchical random irregular honeycombs strongly depend on the thickness of the first-order cell walls if it is at the micro-meter scale, and that if the thickness of the first-order cell walls is at the nano-meter scale, the elastic properties of hierarchical random irregular honeycombs are not only size-dependent, but are also tunable and controllable over large ranges. In addition, the geometrical properties of nano-structured hierarchical random irregular honeycombs are also tunable and controllable.

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) have attracted tremendous research interests due to their exciting optical properties, large surface area, intercalatable morphologies and excellent electrochemically catalytic activity. Acting as the most typical member in TMDCs family, layer-dependent molybdenum disulfide (MoS2) with particular direct bandgap of 1.8 eV in monolayer has been widely applied in various biosensors with high sensitivity and selectivity. In this review, the preparation methods of MoS2, together with MoS2-based biosensors for detecting cells and biomolecules (such as glucose, DNA and antigens) would be summarized. In addition, the current challenges and future perspectives are outlined for the applications of biosensors based on 2D MoS2.

In this research, a novel method is proposed to improve DNA straightening under an applied electric field to facilitate imaging in a liquid phase by modifying the substrate with varying Mg2+ ion concentrations. A two-dimensional network of DNA structures was successfully stretched on Mg2+-modified mica substrates under a DC electric field (1 V, 1 A) and imaged in gaseous and aqueous phases by atomic force microscopy. The results revealed that an optimum concentration of Mg2+ ion (4.17 μmol/ml) allowed DNA straightening under an electric field, thus facilitating its imaging in the liquid phase. Furthermore, DNA adhesion under different concentrations of Mg2+ was measured and a maximum adhesion force of 76.19 pN was achieved. This vital work has great potential in gene knockout and targeted gene editing.

This paper presents an FFT (fast Fourier transform) analytical method for the study of surface structures fabricated by laser interference lithography (LIL). In the work, the FFT analytical method combined with Gaussian fitting is used to determine the periods and pattern distributions of surface structures from frequency spectra. For LIL, the processing parameters of incident and azimuth angles can be obtained corresponding to the period and pattern distribution. This work facilitates the detection of micro- and nano-structures, the analysis of pattern distribution in engineering, and the processing error analysis of LIL.

In this work, the authors propose a method to obtain micro- and nano-structures on the stainless steel mesh (SSM), which showed the potential application for the treatment of water pollution based on its hydrophobicity and oleophilicity. The textured surfaces with the micrometer scale pore array patterns on the SSM are formed by three-beam laser interference lithography. And the nanostructures, such as nanorods, nanowires, and nanoflakes, are obtained on the surfaces of the SSMs after laser irradiation by heating for 70 min at approximately 600 °C under ambient conditions. The results showed that the nanostructures can be easier to grow on the rough surface than the smooth ones. In addition, these nanostructures are also grown on the surfaces of the laser irradiated SSM with the candle soot (LISSM@C). Raman spectrum proves that the nanostructures are α-Fe2O3 and α-Fe2O3/reduced graphene oxide (rGO). The measurement of the contact angle indicates that the oil-water separation can be realized on the LISSM@C after the thermal treatment.In this work, the authors propose a method to obtain micro- and nano-structures on the stainless steel mesh (SSM), which showed the potential application for the treatment of water pollution based on its hydrophobicity and oleophilicity. The textured surfaces with the micrometer scale pore array patterns on the SSM are formed by three-beam laser interference lithography. And the nanostructures, such as nanorods, nanowires, and nanoflakes, are obtained on the surfaces of the SSMs after laser irradiation by heating for 70 min at approximately 600 °C under ambient conditions. The results showed that the nanostructures can be easier to grow on the rough surface than the smooth ones. In addition, these nanostructures are also grown on the surfaces of the laser irradiated SSM with the candle soot (LISSM@C). Raman spectrum proves that the nanostructures are α-Fe2O3 and α-Fe2O3/reduced graphene oxide (rGO). The measurement of the contact angle indicates that the oil-water separation can be realized on the LISSM@C...

A one-step lithography method based on a superlens is proposed to fabricate diffraction-unlimited metallic patterns. By controlling the material parameters and the distribution of the impinging energy, various phenomena, such as periodic nanonetworks, ultrathin nanowires (sub-50-nm feature size), and variable-sized nanoparticles (ranging from sub-10 nm to several hundreds of nanometers), are fabricated using a 1,064-nm nanosecond laser. The evolution pathway of such phenomena is explained by the dewetting process of metallic films. The direct-writing performance of a transparent material with a superlens is studied, and the maximum etching depth of Si gratings can reach 2 µm under a single laser pulse, with fine profiles.

Periodic and quasi-periodic structures on silicon surface have numerous significant applications in photoelectronics and surface engineering. A number of technologies have been developed to fabricate the structures in various research fields. In this work, we take the strategy of direct nanosecond laser interference lithography technology, and focus on the silicon material to create different well-defined surface structures based on theoretical analysis of the formation of laser interference patterns. Two, three and four-beam laser interference systems were set up to fabricate the grating, regular triangle and square structures on silicon surfaces, respectively. From the AFM micrographs, the critical features of structures have a dependence on laser fluences. For a relative low laser fluence, grating and dot structures formed with bumps due to the Marangoni Effect. With the increase of laser fluences, melt and evaporation behaviors can be responsible for the laser modification. By properly selecting the process parameters, well-defined grating and dot structures can been achieved. It can be demonstrated that direct laser interference lithography is a facile and efficient technology with the advantage of a single process procedure over macroscale areas for the fabrication of micro and nano structures.

Simple closed form results for all the elastic constants of the first order nano-sized hexagonal honeycombs and body-centred-cubic (BCC) open-celled foams, and their self-similar hierarchical cellular materials are obtained in this paper. It is found that if the cell wall/strut thickness of the first order honeycomb or open-celled foam is at the nano-meter scale, the elastic properties of the hierarchical porous materials are not only size-dependent owing to the surface elasticity effects, but also tunable because the amplitude of the initial surface stress/strain is adjustable and controllable. In addition, the cell diameter, cross-sectional area and volume, the total surface area and the electric capacitance of the nano-structured hierarchical honeycombs and open-celled foams can be controlled to vary over a large range. What is more, if the surface modulus of the solid material is negative, a nano-structured hierarchical cellular material could possibly be controlled to collapse automatically.

This paper presents a method of laser interference nanolithography for the formation of interference patterns on the resist using a fiber semiconductor laser with a wavelength of 405nm. In the method, surface pattern structures are fabricated through the control of the incident angles of two interfering beams, the exposure dose of laser radiation and the development time. The angle adjustment becomes more convenient and the influence of environmental variations on the system has been reduced due to the use of fiber optic components. In the work, a feature size of down to 63nm and a pattern period of 215nm were achieved. The experimental results have shown that the method can be used for low cost micro and nano fabrication of periodical surface patterns with the features of low cost, simplicity and flexibility. (2013) Trans Tech Publications, Switzerland.

The electrophysiological properties of excitable cells can reflect the state of cells. However, the action potentials (APs) are weak and difficult to detect. The influencing factors of AP measurement are studied by analyzing the equivalent circuit model between cardiac myocyte and microelectrode. After simulation experiments, the improved methods of the parameters that greatly influence on the signal measurement were adopted, and the dialectical relationship among the parameters was analyzed. Aiming at the problem of low signal resolution in planar microelectrodes array, the adjusted methods of electrode parameters were proposed. The experimental results show that the proposed method can change some parameter serious influencing on signal measurement, and is useful to obtain the state between APs and cell more accurately.

This paper presents a method for the quantitative imaging and analysis of SMCC-7721 cells using an atomic force acoustic microscope (AFAM). In this work, an AFAM was used to study the surface, intracellular structure and elasticity mapping of SMCC-7721 cells, and both topographic and acoustic images of the cells were obtained. In the experiment, the SMCC-7721 cells were treated with 4% paraformaldehyde (PFA), and untreated and treated with Thymidine (TdR). The imaging results were compared and analyzed. The quantitative analysis result indicates that the AFAM is a useful tool to measure the surface, intracellular structure and the elasticity property of the cells.

In this paper, we developed a method to drive the oscillation of AFM conductive probe cantilever for stimulating living single cells in liquid with an AC-voltage excitation. We took a copper foil stuck at the bottom of the petri dish as an electrode and the AFM conductive probe was used as both a nano electrode and an actuator to stimulate the living cells when a bias voltage was applied to the electrodes. The voltage and distance between the two electrodes can be adjusted to obtain various required stimulation effects. In the work, the application of electrostatic force and electrolysis for stimulating living cells with bias voltages was analyzed. The experiment results have shown that the method is able to perform controllable stimulation and precise positioning of cells with the AFM The developed system is an efficient stimulation tool for the study of cellular physiological behaviors.

Elastic properties of carcinoma cells are frequently measured from which malignant cells could be distinguished from their benign counterparts. However, the viscoelastic properties of cancerous cells do not receive their deserved attention since biological cells are more or less viscous. In this regard, the goal of this study is to explore, verify and quantify the viscoelastic properties of human liver cancerous cells (SMCC-7721 cells). To accomplish this objective, creep tests are performed on single 7721 cells by using the constant force delay mode of atomic force microscopy (AFM), and the resulted indentation depth-time curve is fitted by a theoretical model which takes profile of AFM probe and viscoelastic constitution of 7721 cells into consideration. The result indicates that this theoretical model provides good fitting coincidence and the order of magnitude of the extracted parameters also coincides with that of previous studies.

We present a new method to transfer the three dimensional (3D) porous layer from InP wafer based on the disturbance, during electrochemical etching of n-InP (100) with chronopotentiometry with current ramp in 3 mol-L−1 NaCl solution. The potential bursting phenomenon was observed due to the disturbing instantaneously. In addition, the correlation between the amplitude of the potential and the porous layers separated from the InP wafer was discussed.

In this paper, the HL7702 cells were cured with 4% paraformaldehyde for different time durations. The atomic force microscope (AFM) and atomic force acoustic microscope (AFAM) were used to observe the surface and subsurface properties of the cured cells. The structures of the cells were changed with the curing time including the cytoskeleton, the shape, the height and the roughness of the cells. The lamellipodium can be seen for the curing time of 15 minutes with 4% paraformaldehyde. The optimal curing time was 15 minutes. This work provides a method for the study of cured cells in biomedicine.

A method for the fabrication of micropolarizer arrays by electron beam lithography was presented. The experimental results have illustrated the influences of exposure dose on the performance parameters of wire grids. The maximum transmittance and extinction ratios of wire grid arrays were obtained in the visible spectrum and the comparison results of the different depths of wire grids demonstrate the superiority of high depths. The performance of the two structures has shown that this work offers the possibility to improve the properties of the micropolarizers.

This paper presents a facile approach for the rapid and maskless fabrication of hierarchical structures by multibeam laser interference. In the work, three- and four-beam laser interference lithographies were proposed to fabricate ordered multiscale surface structures instead of six or more beam interference with a complicated system setup. The pitch and shape of hierarchical structures can be controlled by adjusting the parameters of incident light. The experiment results have shown that the hierarchical anisotropy and isotropy surface structures can be fabricated by this method with the control of the parameters of each incident beam, which is in accordance with the theoretical analysis and computer simulations.

This paper presents the study of Ti-6Al-4V alloy modification by two-beam laser interference. In this work, two-beam laser interference was used to pattern groove structures on Ti-6Al-4V alloy surfaces, and the laser fluences with different exposure durations were applied to the process in the air. The roughness and contact angle of the surface were studied before and after the laser interference lithography (LIL) treatment. The results showed that the surface with groove structures increased the roughness to around 1μm and reduced the contact angle to around 44 °. MG63 cells were cultured on the polished and grooved surface. The SEM images showed that the cells were grown along in the direction of the grooves and randomly oriented on the polished surface.

This paper explores the changes of DNA network structures with different solution concentrations of DNAs and ferric ions by atomic force microscope (AFM). AFM is a powerful tool for both the observation and manipulation of biological molecules. DNA is an important life molecule to record the biological information and it is also a natural nano material which has great potential for the fabrication of molecular devices. The mica with a flat surface can be used as a substrate for observing DNA molecules, but the combination with DNA is not controllable, and the mica surface has to be modified. Here, we used ferric ions to induce DNA network structures and they were investigated by AFM. It was observed that when the concentration of DNA solution was low, there was no DNA network structures formed, and when the concentration of DNA solution was increased to 200–280ng/ul, DNA network structures were clearly formed.

The fogging phenomenon affects light transmittance on the surface of a transparent substrate, and what’s more, the substrate surface will therefore become wet, which leads to some secondary problems such as corrosion and deterioration etc. There are two ways to solve the antifogging problem. One is hydrophilic and the other is hydrophobic. However, hydrophilic antifogging method cannot change the “wet” nature. The anti-moisture function on Ephemera pictiventris mcLachlan compound eyes surface was studied in this paper, and the compound eyes structure was characterized via Scanning Electron Microscope (SEM) and Laser Scanning Confocal Microscope (LSCM). Then anti-moisture mechanism was explained by Cassie model based on above structure data. Next artificial Ephemera pictiventris mcLachlan compound eyes surfaces were prepared by direct three-beam Laser Interference Lithography (LIL) and Colloidal Lithography (CL) respectively, and further wettability was also discussed. Results show that the compound eyes surface of Ephemera pictiventris mcLachlan exhibits striking hydrophobic anti-moisture property. The compound eyes are composed of hundreds of micron-scale ommatidia closely arranged on ellipsoidal surface. The morphology of each ommatidium is almost uniform and made up of two parts. The upper part is spherical and the lower is frustum of a cone with the upper spherical diameter of about 20 μ m and the overall height of about 11 μ m. There is no more tiny nanostructure on the ommatidia surface. The morphology and dimension of bionic convex array surface that is artificial compound eyes surface are close to the parameters of true compound eyes surface. The water contact angle (WCA) value of this surface can reach 123°, showing a strong hydrophobic property, after etched 2 min by HF with the concentration of 5%. The mechanism analysis results show that the calculated apparent WCA value is 119.2°, in agreement with the experimental value. Also the apparent WCA value increases with the increase of intrinsic WCA value. The smaller the ratio of ommatidia radius, the greater the apparent WCA value. When the ratio is less than or equal to 0.4, the apparent WCA value is up to 150° or more. The static WCA value and water sliding angle (WSA) value of artificial optimized Ephemera pictiventris mcLachlan compound eyes surface with the feature size of 350 nm are 160°±5° and 2°, respectively, showing excellent superhydrophobic and self-cleaning functions. The result indicates that Ephemera pictiventris mcLachlan compound eyes is dry-style antifogging function structure surface. The synthesis of proper size, compact arrangement of ommatidia and arc shape of the compound eyes is one of the origins of hydrophobic antifogging function. Artificial optimized compound eyes surface shows excellent superhydrophobic and self-cleaning functions.

Nanomanipulation is an important technology to fabricate and assemble nanostructures, especially for the asymmetrical structures. This paper presents a method of manipulation of single nanowires on structured surfaces by nano grippers in a scanning electron microscope (SEM). In the method, the structured surfaces of substrate were fabricated by two-beam laser interference lithography. Single nanowires were manipulated on the structured surfaces by nano grippers in the SEM. The method uses a pattern to solve the problem that a single nanowire is too tiny to be picked up and manipulated with nano grippers.

This paper aims to obtain the simple closed-form results for the combined effects of surface elasticity, initial stress/ strain, and material Poisson ratio on the bending stiffness, natural frequency and buckling force of nanowires and nano-plates. The results demonstrate that all these properties of nanowires or nanoplates can be designed either very sensitive or not sensitive at all to the amplitude of an applied electric potential; show how much of those properties can be controlled to vary; and thus provide a reliable guide to the measurement of the Young’s modulus of nanowires/nanoplates and to the design of nano-devices, such as nano-sensors or the cantilever of an AFM.

In this study, we presented an investigation of mechanical properties by AFM nanoindentation on human hepatocellular carcinoma cells treated with fullerenol for 24, 48 and 72 h. AFM nanoindentation was routinely applied to investigate the morphology and biomechanical properties of living carcinoma cells, and adhesion phenomena (negative force) were detected in the obtained force-displacement curves. Conventionally, Hertz contact model has been widely used for determination of cell elasticity, however this contact model cannot account for adhesion. Alternatively, JKR contact model, as expected for adhesion circumstance, has been applied to fit the obtained force-displacement curves. In this investigation, we have derived both the work of adhesion and the elastic modulus of biological cells (human hepatocellular carcinoma) under fullerenol treatment. The results show that the chosen JKR model can provide better fitting results than Hertz contact model. The results show that both Young’s modulus and work of adhesion exhibit significant variation as the treatment time increases. The calculated mechanical properties of elastic modulus and work of adhesion can be used as an effective bio-index to evaluate the effects of fullerenol or other anticancer agents on cancer cells and thus to provide insight into cancer progression in the treatment.

Reflection loss on the optical component surface is detrimental to performance. Several researchers have discovered that the eyes of moths are covered with micro- and nanostructured films that reduce broadband and wide-angle light reflection. This research proposes a new type of moth-eye subwavelength structure with a waist, which is equivalent to a gradient refractive index film layer with high&ndash, low&ndash, high hyperbolic-type fill factor distribution. The diffraction order characteristics of a moth-eye subwavelength structure are first analyzed using a rigorous coupled wave analysis. The moth-eye structural parameters are optimized within the spectral range of 2&ndash, 5 &mu, m using the finite-difference time-domain method. The experimental fabrication of the moth-eye structure with a waist array upon a silicon substrate is demonstrated by using three-beam laser interferometric lithography and an inductively coupled plasma process. The experimental and simulation results show good agreement. The experimental results show that the reflectivity of the moth-eye structure with a waist is less than 1.3% when the incidence angle is less than 30&deg, and less than 4% when the incidence angle is less than 60&deg, This research can guide the development of AR broadband optical components and wide-angle applications.

A simple and inexpensive one-step laser cladding method is reported to make the stainless steel mesh underwater superoleophobic. The micro/nanoscale morphologies were created via cladding a copper foil onto the stainless steel mesh using the nanosecond laser marking system. The fabricated stainless steel mesh has the underwater superoleophobic property with oil contact angles greater than 150°. Based on the special wettability, the fabricated stainless steel mesh is used to separate the light oil–water mixtures, and the separation efficiencies are >98.3%.

Four-beam laser interference is shown to stimulate the self-organisation of periodic two-dimensional arrays of nanoislands on the surface of GaAs/InGaAs/GaAs epitaxial structures. (Self-organisation is here taken to mean processes that determine the island size.) The island size distribution has two well-defined maxima. The smaller islands (~5 nm) form inside each heat-affected zone, and the larger islands (~15 nm), at the periphery of such zones. The island width is a factor of 20 — 60 smaller than the standing wave period, which can be accounted for in terms of the elastic stress on the surface of the epitaxial film.

The crossing porous structure of InP has been obtained by electrochemical etching in NaF solutions. The behavior of the periodic oscillation occurs at different potential ranges for the different concentrations of solutions, and it will disappear with the concentration of the solution decreased. The scanning electron microscope (SEM) image shows that the pores have two directions on the surface and are perpendicular to each other. The two directions are assigned to [0 1 1] and [ 0 1 ¯ 1 ], respectively. The SEM image of the cross-section also shows that the two directions are assigned to [1 1 1]B and [ 1 1 ¯ 1 ¯ ]B. Both are due to the selective etching of F− ions. The crossing porous structure of InP is a very promising feature for the three-dimensional structure of III–V compound semiconductors for photonic band gap materials.

In this work, an effective method was presented to obtain a specific micro and nano dual-structures by amplitude modulation in multi-beam laser interference lithography (LIL). Moire effect was applied to generate the amplitude modulation. The specific intensity modulation patterns can be obtained by the control of the parameter settings of incident laser beams. Both the incident angle and azimuth angle asymmetric configurations can cause the amplitude modulation in the interference optic field and the modulation period is determined by the angle offset. A four-beam LIL system was set up to fabricate patterns on photoresist and verify the method. The experimental results are in good agreement with the theoretical analysis.

Periodic structures are of increasing interest in many fields such as nanotechnology and biotechnology among others. Laser Interference Lithography (LIL) has been widely studied for the fabrication of periodic structures. However, a LIL tool for the nanoscale structuring of materials that can scale beyond laboratory prototypes into cost effective industrial processes is not yet defined. In this work, we describe a versatile and automatic high-power multiple beam interference lithography system design capable of overcoming the limitations of manual setups. Using this system, we have successfully processed photoresist samples on the whole surface of 3in. silicon wafers, demonstrating the applicability of this prototype to a wide range of device fabrication.

High throughput and low cost fabrication techniques in the sub-micrometer scale are attractive for the industry. Laser interference lithography (LIL) is a promising technique that can produce one, two and three-dimensional periodical patterns over large areas. In this work, two- and four-beam laser interference lithography systems are implemented to produce respectively one- and two-dimensional periodical patterns. A high-power single pulse of ∼8 ns is used as exposure process. The optimum exposure dose for a good feature patterning in a 600 nm layer of AZ-1505 photoresist deposited on silicon wafers is studied. The best aspect ratio is found for a laser fluence of 20 mJ/cm2. A method to control the width of the sub-micrometer structures based on controlling the resist thickness and the laser fluence is proposed.

Self-cleaning effect of micro- and nanostructures has attracted much attention in the field of nanotechnology. In this work, we present experimental work that reveals the relation between the surface areas of dual micro- and nanostructures and wettability of materials. It is an effective method to utilize laser interference lithography (LIL) to fabricate the bionic dual micro- and nanostructures of lotus leaves, and increase the surface areas of materials. Dual micro- and nanostructures have been fabricated on iron-nickel alloy surfaces. The experimental results show that the contact angle (CA) has a close relationship with the surface area of the dual micro- and nanostructures.

The rapid development of emerging technologies in the areas of traditional mechanical machinery, electronic engineering and advanced micro-processors, has brought a great opportunity for the development and applications of biomedical engineering instruments with robot technology in traditional medicine. At the same time, because of the progress of human civilisation and improvement of living standards, people have higher and more critical requirements to the bio-medical technology. Under these circumstances, researchers from all over the world have made fruitful achievements in promoting the development of medical robots, medical automation and robotic manipulation. Medical robot engineering is a discipline which applies the latest results of research and development to the medical treatment and rehabilitation. This paper reviews a range of widely-used applications of the micro-robot and rehabilitation robots to provide an overview and understanding of the current development in this area.

The biggest challenge of the practical applications of metamaterial-based perfect absorbers remains on the architectural design structure to engineer a system capable to achieve a near unity absorption, large absorption bandwidth and tunable resonance frequency and absorption strength. We propose and demonstrate an active visible and near-infrared metamaterial absorber formed by a sandwich of gold square metallic patch-vanadium dioxide thin film-gold layer. It shows a high absorptance up to 86% at the external temperature stimuli of 30°C, and about 30% at 85°C in the wide wavelength range from 0.9 µm to 1.5 µm. The proposed absorber has potential applications in active thermal control of electronic, optical and thermal devices.

Since the invention of the atomic force microscope (AFM), it has been widely applied in biomedicine. One of the most important applications is used as an indenter tool to do the indentation experiment in order to get the mechanical properties of cells. In this paper, SW480 cells were used as the test subjects. Through the analysis of the contact and indentation, Young's modulus (E), which is an important parameter of cancer cells, has been estimated. Experimental results show that different mechanical models should be chosen to calculate the E in different indentation depths. Here, the E of SW480 cells was (2.5 ± 0.8) KPa at the indentation depth of 99 nm.

Optically-induced dielectrophoresis (ODEP) provides an effective method for the manipulation of microparticles using a direct projection of light pattern onto the surface of a photoconductive material. In this work, an a-Si:H-based ODEP chip was developed with a 0.5µm photoconductive thin film. A new scheme for the establishment of an electrical connection with a mold in the thin film deposition process was presented. In the experiment, living cells were manipulated and collected using the developed ODEP chip. The results have shown that the cells can be collected successfully with the dielectrophoresis force. In the cell manipulation process, only 0.2 mW optical power was used to turn on the ODEP chip, corresponding to the density of 0.5 mW/cm2. The optical intensity was much lower than that by using typical ODEP chip and it reduced the focusing requirements.

A method for fabricating a thin film micropolarizer array using electron beam lithography and inductively coupled plasma-reactive ion etching (ICP-RIE) is presented. In this work, a 100 nm aluminum layer was sputtered on the substrate via magnetron sputtering, and a 140 nm layer of polymethyl methacrylate (PMMA) photoresist was spin-coated at 4000 rpm for 50 s, and prebaked at 180 °C for 120 s. The grating patterns were transferred from the photoresist to the aluminum layer using ICP-RIE. The micropolarizer array was fabricated with many aluminum wire grid polarizers, whose period range was from 140 nm to 200 nm, and the extinction ratios of the different periods were obtained in the visible spectrum. The optical performance measurement has shown that this work provides a feasible method to fabricate wire grid polarizer arrays.