The ultra-precision grid encoder is the key technology of the immersion lithography scanner for 32-7 nm node. Firstly, by analyzing the requirements and layout of the grid encoder position measurement system of the immersion lithography scanner, the basic requirement of a special grid encoder for the scanner is proposed. Secondly, for the present grating encoder, research on the basic optical path, phase detection, resolution multiplication, off-axis/rotation tolerance, and dead-path restrain scheme is reviewed and analyzed. Then, the key problems of the present scheme in the application of the lithography scanner are proposed. Thirdly, to address the required nanometer accuracy for the instrumental error of the grid encoder, the research on nonlinearity, dead-path, thermal drift, and wave-front distortion error are reviewed and analyzed; and the key problems to achieve sub-nanometer accuracy for the grid encoder are proposed. Finally, the above review is summarized, which can serve as a reference for the special grid encoder of immersion lithography scanner.

To address the low success rate of droplet separation and the inaccurate daughter droplet volume on the square electrode, a digital microfluidic chip with fan-shaped electrode was proposed and its separation effect was studied. After analyzing the factors affecting droplet separation on the square electrode, the fan-shaped electrode was designed in combination with the advantages of crescent electrodes, dumbbell electrode, and bow electrodes. Compared with traditional separation, the novel chip can adjust the initial position of the droplets before separation to ensure the smooth shrinkage of the droplet during the separation process and improve the success rate and precision of the droplet volume. Deionized water was used as the experimental object to verify the separation effect of the novel chip. The results show that the success rates of droplet separation at different channel heights on novel electrodes are higher than that on conventional electrodes. The average error of daughter droplets is controlled at ±2%, and the coefficient of variation is as low as 1.83%. The separation accuracy can be further improved by reducing the size of the separation electrodes. The experimental results indicate that the separation success rate and splitting precision on digital microfluidic chip with fan-shaped electrode was significantly improved.

The ceramic hip ball is one of the important parts in artificial hip replacement surgery. In order to realize the high-efficiency and high-quality processing of the ceramic hip ball, a rotating ultrasonic-assisted spherical grinding device was built in this study. First, the basic principle of rotary ultrasonic-assisted spherical grinding was introduced. Then, according to the motion characteristics of the device, the equation of the trajectory of the abrasive particle was established. Combined with the kinematic equation, the kinematic trajectory analysis of the abrasive grains in the processing state was carried out, the forming law of the spherical microtexture was studied in detail. Finally, an ultrasonic-assisted grinding of ceramic artificial hip joint ball experiment was performed. The results show that, at tool speed of 3000 r/min and workpiece rotation speed of 2011 r/min, the average surface roughness is 96 nm, and the line roughness average is 56 nm. When the rotational speed of the ceramic ball and grinding wheel are mutually prime, the texture distribution of the spherical surface is more uniform, which provides an important theoretical basis for the optimization of processing parameters.

In order to realize the rotation control of an electromagnetic levitation micromirror from -180° to +180°, the electromagnetic levitation, electrostatic drive, and closed-loop angle control used in this system were studied. First, the stator and rotor structures were designed and fabricated. Then, the relationship between levitation height and the frequency and amplitude applied to the coil were simulated and tested. The experimental results showed good agreement with the simulation results. On the basis of the analysis of the driving principle of variable capacitance, the rotation control experiment was performed, which showed that the rotor can rotate under the energizing condition in the phase sequence. Finally, a closed-loop control system with high-precision capacitance detection was introduced. The experimental results show that when the excitation current p-p value is 0.5 A and the excitation frequency is 20 MHz, suspension of the rotor at height of 100 μm can control the specified angle and meet the control requirements of the electromagnetic suspension micromirror.

Based on the unique physical properties of noble metal nanoparticles, a fluorescence sensor with signal amplification function was designed for detecting the concentration of dopamine. Based on the effect of metal fluorescence enhancement, the fluorescence signal was amplified by adding a spacer layer between the gold nanoparticles and fluorophore. First, the aptamer chemically modified with an SH bond was mixed with a gold nanoparticle solution to form a stable Au-S bond structure. Then, the DNA labeled with fluorescent groups were bound due to the complementary base pairing. The distance between the fluorophore and the surface of the gold nanoparticle was adjusted by changing the amount of base A. At the same time, the concentration ratio between the aptamer and gold nanoparticles and the pH of the reaction environment were optimized to obtain the best amplification efficiency. Finally, different concentrations of dopamine were tested. The experimental results indicate that at a certain concentration ratio between the gold nanoparticle solution and aptamer, the maximum fluorescence enhancement is 2.35 times at the isolation layer thickness is 27 base A. Dopamine concentration detection has a linear range of 20-100 nmol/L. The detection limit is 20 nmol/L. It can effectively regulate the isolation layer thickness at the nanometer level, providing a stable signal amplification strategy.

The electrochemical corrosion resistance properties of nano Fe-Al/Cr3C2 composite coating were tested. The ideal amount of nano Fe-Al/Cr3C2 reunion-granulation particle to be added was determined. Using three-electrode system, the electrochemical corrosion resistance properties of five kinds Fe-Al/Cr3C2 composite coatings were tested. These were micro Fe-Al/Cr3C2 composite coating, nano Fe-Al/Cr3C2 composite coating, and composite coating with additional 5%, 10%, and 15% nano Fe-Al/Cr3C2 reunion-granulation particles, respectively. Zview software was used to fit the AC impedance spectrum in order to analyze the electrochemical corrosion resistance action of coatings. SEM was used to analyze the corrosion surface of coatings. The results indicate that the best electrochemical corrosion resistance property of composite coatings was obtained by adding 5% nano Fe-Al/Cr3C2 reunion-granulation particles. Compared with other coatings, the coating with added 5% nano Fe-Al/Cr3C2 reunion-granulation particles has maximum self-corrosion potential of -0.775 V and minimum self-corrosion current of 0.280 mA/cm2. When the content of nano granulated particles is lower than the optimum value, the electrochemical corrosion resistance properties of coatings are because the content of nano granulated particles is too low to improve density and reduce pore size. When the content of nano granulated particles is higher than the optimum value, the electrochemical corrosion resistance property of coatings are nano granulated particles makes surface of coatings showing high chemical energy.

In order to increase the stability of the inductive oil contaminant detection sensor and improve the detection accuracy of ferromagnetic and nonferromagnetic contaminants, an inductive oil contaminant detection sensor with built-in magnetic nanoparticles was designed in this paper. The solenoid coil was filled with a nanoparticle layer which adsorbs the pollutant particles and enhanced the magnetic field strength of the detection area, enhancing the magnetization and eddy current effects. A 300 μm microchannel was made using the model material, which passes through the sensing unit. Ferromagnetic and non-ferromagnetic contaminants can be distinguished when contaminants pass through the microchannel through the sensing unit. At the same time, two sets of contrast experiments were carried out using two sensors with and without magnetic nanoparticle layers. The experimental results show that the inductive oil detection sensor of magnetic nanomaterial has higher detection accuracy and lower detection limit. The detection accuracy of ferromagnetic particles of 20-70 μm improved by 20%-25%, while that of nonferromagnetic particles of 80-130 μm improved by 16%-25%. The method is based on microfluidic detection technology, and has the advantages of small volume and high detection precision. At the same time, it provides technical support for the rapid detection of hydraulic oil contaminants, which has great significance for fault diagnosis and life prediction of hydraulic systems.

In order to solve the problem that the piezoelectric vibration energy harvesting structure is difficult to meet the acquisition requirements of wide frequency band, 3D and high efficiency at the same time, a piezoelectric vibration energy harvester structure with the concentrated mass replaced by Z-type beam was proposed. Nonlinear mass was introduced by the Z-type beam structure, which enabled more modal of the harvester to be concentrated in the low frequency range, increased the acquisition frequency band, and realized the 3D energy harvesting function of the harvester by the instability of the horizontal and longitudinal Z-type beam structure. The dynamic characteristics of the Z-type beam after increasing the width were analyzed, and the energy acquisition performance of the piezoelectric array was discussed. Models and experimental platforms were built for simulation and experimental verification. Then, the dynamic characteristics of the Z-type piezoelectric beam was compared with those of the spiral beam structure and classic cantilever beam mass structure. The simulation and experimental results show that when the beam has seven folded layers, the number of modes with frequency within 50 Hz can reach nine, and in the 1-100 Hz range and 1 Hz harmonic excitation, the peaks of the forward acquisition voltage-frequency curve reaches up to four and are mainly concentrated in the 0-40 Hz range. The maximum open circuit voltage is up to 16 V, greatly widening the acquisition frequency band. The maximum open circuit voltage peaks in both the horizontal and vertical directions are above 10 V, while the peaks of the horizontal and vertical acquisition voltage-frequency curves are greater than four, achieving 3D energy acquisition. The maximum output power reaches 0.18 mW when the load is 10 kΩ. When the width of the Z-type beam is increased to 100 mm, the number of modes is greater than 30 in the range of 200 Hz. The peak number of acquisition voltage curves of double patch in series is up to four. The maximum voltage reached 14 V, which proves that the Z-beam is suitable for the arrangement of the piezoelectric array.

A method for controllable fabrication of an anti-fouling and self-cleaning surface with micro/nano lotus-like structures on 6061-T6 aluminum alloy was developed in this paper. The facile and low-cost fabrication process consisted of shot blasting, electrochemical oxidation, and surface modification with fluoroalkylsilane. The micro-pit structure was fabricated by shot blasting the aluminum alloy surface. The nano-coral structure was prepared by electrochemical oxidation. Then, the anti-fouling and self-cleaning surface with micro/nano structures were fabricated after fluorination treatment. Lastly, the surface morphology, contact angle, surface adhesion energy, self-cleaning, and corrosion resistance of the prepared aluminum alloy substrate were analyzed. The results show that the maximum contact angle and minimum rolling angle of the aluminum alloy surface are 153° and 5°, respectively, which have good anti-fouling and self-cleaning properties, after shot blasting and electrochemical oxidation treatment.In addition, the surface hardness increases from 90HV to 392HV. The potentiodynamic polarization curve shows that the surface current density decreases by two to three orders of magnitude compared with that before treatment, and the surface wear resistance and corrosion resistance are improved significantly.

A novel piezoelectric microspray dispensing system was designed based on a compliant mechanism. The system consisted of a glue supply device, driving device, and pin-impact valve. The motion characteristic of the dispensing system was that the elastic deformation of the compliant mechanism drived the colliding needle to move in a straight line to and fro, so that the opening and closing of the colliding needle valve could perform the function of microspray dispensing. The driving force, output displacement, and frequency characteristics of the dispensing system were obtained by using a pseudo-rigid-body method. The results show that the maximum of driving force, output displacement, and frequency of the system are 56.4 N, 808 μm, and 245 Hz, respectively. Thus, the driving force, stroke, and dispensing speed of the dispensing system can be guaranteed. The prototype was built and the effects of duty cycle, amplitude, frequency of driving voltage signal, and viscosity of glue on the droplet diameter were analyzed experimentally; the conditions for the formation of normal droplets were also determined. The experimental results show that the highest dispensing frequency of the system is 210 Hz, the minimum diameter of the droplets is 630 μm, and the consistency error of the droplets is 5.62 %. In a word, the advantages of the proposed dispensing system are verified, which provides a new concept for the design and application of microspray dispensing system.

Traditional piezoelectric capturing systems have the disadvantages of narrow work bandwidths and fragile piezoelectric ceramic materials, which are unable to meet the requirements of wearable, miniaturized, or portable devices. This paper reports on high performance composite films based on BaTiO3/Graphene Oxide/polydimethyl siloxane (BaTiO3/GO/PDMS) with different GO content. GO with a large specific surface and strong fluidity was employed as a carbon-based conductive phase material to form micro-capacitors in the ferroelectric composite and thus enhance the piezoelectric performance of the given sample. The as-prepared BaTiO3/GO/PDMS composite films with 0.6 wt% GO showed a dielectric constant of 185 and a conductivity of 8.5×10-5 S/m. In addition, a remnant polarization of 13.47 μC/cm2 could be obtained, which is 28% higher than that of films of pure BaTiO3/PDMS. In contrast, the synthesized BaTiO3/GO/PDMS composite film exhibited a maximum output voltage of approximately 7.71 V, which is approximately 2.78 times higher than that of the film without GO. The performance of lead-free flexible piezoelectric nanogenerators was significantly enhanced after being compounded with GO materials. Moreover, an unsymmetrical interdigital harvester with BaTiO3/GO/PDMS piezoelectric materials was fabricated. The results indicated that the output voltage of the harvester compounded with GO increased and that the -3 dB bandwidth of harvesters increased from 8.7 Hz (without GO) to 11.2 Hz (with GO). Therefore, the proposed BaTiO3/GO/PDMS lead-free flexible composite piezoelectric nanogenerator presents great prospects in flexible energy harvesting.

In order to achieve ultra-precision polishing of the workpiece surface, a UV-induced nanoparticle colloid jet processing system was established. The hydrodynamic characteristics, polishing process, and ultra-smooth surface morphology of the UV-induced nanoparticle colloid jet processing of two nozzles with different cavity structures were studied. Firstly, conical and cosine opto-hydraulic coupling nozzles were designed according to the requirements of opto-hydraulic coupling. Then, three-phase flow simulation of non-submerged jet was carried out for two kinds of opto-hydraulic coupling nozzles, and the flow track and flow field distribution of nanoparticles were compared and analyzed. Next, light-coupled colloid jet polishing experiments were carried out on the same single crystal silicon workpiece with two kinds of nozzles using titanium dioxide nanoparticle colloid as polishing fluid. Finally, the surface before and after polishing was characterized and compared. The results show that the flow velocity (20.73 m/s) and dynamic pressure (2.5 MPa) obtained by the cosine nozzle are higher than that of the conical nozzle with flow velocity (7.12 m/s) and dynamic pressure (0.2 MPa). The average residence time of nanoparticles in the cosine nozzle (0.00 5 s) is shorter than that of the conical nozzle (0.023 s). Under the same polishing parameters, the surface roughness (Rq 0.810 nm, Ra 0.651 nm) of the workpiece polished by cosine nozzle is lower than that of the conical nozzle. Using the cosine nozzle in UV-induced nanoparticle colloid jet processing can result in lower surface roughness than with the conical nozzle.

Cell culture is the basis of cell research. In order to realize long-term dynamic culture and real-time observation of cells in a microfluidic chip, a microfluidic cell dynamic culture device was designed and fabricated. First, based on the "split" arrangement idea, a three-dimension model of the culture box, control box, and pump box were set up using the software, SolidWorks; hardware and software were designed taking the functional demands into consideration. Second, based on the Comsol software platform, the method of Joule heating was used to analyze the thermodynamic characteristics of the device's heater, namely, ITO glass; the temperature distribution was then obtained from the simulation results. Third, the entire device model was established and its stability was tested. Finally, cell culture experiments were performed. The split design can effectively reduce the volume of the incubator and achieve compatibility between the incubator and the microscopic observation system. In addition, the temperature and humidity of the device are stable, cell growth is in the "S" trend, and the cell survival rate is more than 95%. The split-body cell dynamic culture device offers a satisfactory environment condition for cell culture, in which cells can be observed in real time. As such, the device can satisfy relevant design requirements.

The life of a satellite electric slip ring is approximately 100,000 rounds. To verify the reliability of a column slip ring at the end of one million rounds, we performed a two-million-round life test. As slip rings contain both a single brush wire and a brush bunch, this test compareed the transmission error of different types of signals that pass through single brush wires and brush bunches. The structure of the brush wire was vital in determining the transmitting stability of a space electric slip ring. This study verified the main influencing factors, such as different temperature, revolving speed, and vacuum performance. The transmission errors of CAN and RS422 signals indicate that brush bunch rings, which are characterized by a 0.6% voltage drop and no transmission error, are more stable than single brush wire rings in a vacuum with a signal transmission speed of 500 kbps. The maximum voltage drop of single brush rings is over 100% and transmission errors are approximately 16.1%. This proves that the design of brush bunches can effectively improve the reliability of signal transmission and prolong the service life of slip rings; this knowledge is of significant value in determining the reliability of satellites.

Three types of optical fiber lasers that can emit one, two, or three wavelengths simultaneously were researched and experimented on. The three types of lasers could be applied to measure displacement, step height, and absolute distance, respectively. By employing the characteristic that a fiber Bragg grating could only reflect a Bragg wavelength, fiber Bragg gratings have been used as the reflective mirrors of the laser resonant cavities and wavelength selectors. As such, a single laser resonant cavity and multiple independent laser resonant cavities with overlapped laser optical paths were constructed with a length of erbium-doped optical fiber in each cavity. Pumped by a 980-nm laser, the optical fiber lasers could emit a single wavelength and multiple wavelengths simultaneously; the value of each wavelength could be determined as needed. Furthermore, the wavelength interval between two adjacent wavelengths could be determined as needed. There is no laser mode competition between the wavelengths, as each wavelength has a stable power and frequency. Wavelength stability can reach up to 10-7, satisfying the precision requirements of measuring displacement, step height, and absolute distance through interferometric methods.

A wear debris detection sensor used to detect inductance and resistance parameters was presented, which could improve the detection sensitivity of the inductive sensor for nonferromagnetic metal particles. The designed sensor mainly consisted of a ring silicon steel sheet and planar coil. The silicon steel sheet enhanced the magnetic field strength of the detection region, making the magnetization effect and eddy current effect of the metal particles more intense, thereby improving the sensitivity of inductance and resistance detection. Through comparative experiments, it was found that the ring silicon steel sheet does not increase the noise of the inductance and resistance detection signals; and both the inductance and resistance detection capability are stronger for ferromagnetic metal particles. For ferromagnetic metal particles, inductance detection is more effective; for nonferromagnetic metal particles, resistance detection is more effective. By combining the inductance detection and resistance detection results, 55 μm iron particles and 115 μm copper particles can be detected using a planar coil with 20 turns. The wear debris sensor provides technical support for online monitoring of hydraulic oil contaminants.

The purpose of this paper is to propose an online noncontact method for measuring the radial rotation error of the spindle and verify the accuracy of the method. This method used a circular grating, two reading heads, an annular plane mirror, and a laser autocollimator. First, the circular grating and annular plane mirror were mounted on the spindle, and the installation error was calibrated in the double center device. Then, the spindle was mounted on the turntable, the double reading head was mounted on the diameter, and the autocollimator was mounted under the flat mirror. During the spindle rotation process, the double reading head could measure the radial motion error of the spindle, and the autocollimator could measure the yaw angle error in the direction of the radial motion error of the spindle. Finally, the radial rotation error of each point of the spindle axis could be calculated according to the radial motion error of one point on the spindle and its yaw angle error in this direction. The results show that within ±12 μm spindle radial rotation error measurement range. The residual error of the proposed method compared with the conventional method is within 1 μm, which verifies the accuracy of the method. The proposed spindle radial rotation error measurement method does not need to use standard balls. It is not affected by the surface roughness, roundness, etc., of the spindle. The measuring device can be embedded into the precision spindle rotary-type device to realize the real-time detection of the spindle radial rotation error.

In order to solve the problem that the tactile sensors for complex three-dimensional carrier surfaces or moving joint parts of robot are difficult to achieve high flexibility and flexibility, a new method based on nano-materials combined with horseshoe shape and pre-stretching process was proposed. Silver nanowires were implanted with a horseshoe shape into the surface of the pre-stretching-treated PDMS film. Then, a type of conductive composite material with high flexibility and stretchability was obtained. The tensile test results show that the resistance of the new type of electrode first decreased and then increased with the increase in stretching rate. After the 50th stretch of 30%, the resistance increase of the electrode relative to the initial value is only 93%. The electrode has a simple manufacturing process, good flexibility, stability, and high transparency. These can meet the requirements of different application conditions and are suitable for many complex applications such as stretching, bending, and torsion.