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Yu Y.,Key Laboratory of Micro Nano Systems for Aerospace | Yu Y.,Northwestern Polytechnical University | Zappe H.,Albert Ludwigs University of Freiburg | Zhang X.,Key Laboratory of Micro Nano Systems for Aerospace | Zhang X.,Northwestern Polytechnical University
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2016

This paper presents the preliminary experimental studies of the influences of structural parameters, including the fill factor, device size, lattice, and nanoaperture shape, on the far-field optical transmission properties through the finite-sized two-dimensional periodic arrays of metallic nanoapertures. Both the lensing effect and the Talbot effect are observed, characterized and analyzed. Light intensity patterns of Talbot revivals at various Talbot distances containing abundant subwavelength hotspots are obtained, and the average size of the hotspots are derived and compared. Some concluding remarks are given to provide an important technological reference for the design and application of such devices according to the current experimental results. © 2016 SPIE.


Yu Y.,Key Laboratory of Micro Nano Systems for Aerospace | Yu Y.,Northwestern Polytechnical University | Zappe H.,Albert Ludwigs University of Freiburg
9th IEEE International Conference on Nano/Micro Engineered and Molecular Systems, IEEE-NEMS 2014 | Year: 2014

Three-dimensional (3D) plasmon Talbot effect is experimentally investigated on three finite-sized, two-dimensional (2D) periodical arrays composed of subwavelength nanoholes with different fill factors. By using water as the output medium, both the focusing behavior and the plasmon Talbot revivals are clearly observed even when the operating wavelength is larger than the array period. And theoretically, with the output material having a refractive index of n, the operating wavelength to realize the plasmon Talbot effect can be enlarged by a factor of n-1. The integral and fractional plasmon Talbot revivals reproduce the device pattern with rich subwavelength hotspots (0.56∼0.72λ) in exactly the same array period, which shows a great prospect for the low-cost, large-scale micro- and nanolithography. The preliminary experimental results indicate that the fill factor doesn't play an obvious influence on the size of the achieved plasmon Talbot hotspots. © 2014 IEEE.


Liu Y.,Key Laboratory of Micro Nano Systems for Aerospace | Liu Y.,Shaanxi Province Key Laboratory of Micro and Nano Electro Mechanical Systems | Yuan W.,Key Laboratory of Micro Nano Systems for Aerospace | Yuan W.,Shaanxi Province Key Laboratory of Micro and Nano Electro Mechanical Systems | And 7 more authors.
Chinese Optics Letters | Year: 2013

The design of a two-dimensional high-frequency electrostatic microscanner is presented, and an improved method for routing isolation trenches is investigated to increase the reliability and mechanical stability of the resulting device. A sample device is fabricated and tested using an optimized micromachining process. Measurement results indicate that the sample device oscillates at inherent frequencies of 11586 and 2047 Hz around the two rotational axes, thereby generating maximum twisting angles of ±7.28° and ±5.63°, respectively, under two square waves of 40 V. These characteristics confirm the validity of our design and satisfy the requirements of a laser projector with VGA standards. © 2013 Chinese Optics Letters.


Jiao W.,Northwestern Polytechnical University | Jiao W.,Key Laboratory of Micro Nano Systems for Aerospace | Yuan W.,Northwestern Polytechnical University | Yuan W.,Key Laboratory of Micro Nano Systems for Aerospace | And 2 more authors.
Journal of Semiconductors | Year: 2015

Geometric nonlinear behaviors of micro resonators have attracted extensive attention of MEMS (micro-electro-mechanical systems) researchers, and MEMS transducers utilizing these behaviors have been widely researched and used due to the advantages of essentially digital output. Currently, the design of transducers with nonlinear behaviors is mainly performed by numerical method and rarely by system level design method. In this paper, the geometric nonlinear beam structure was modeled and established as a reusable library component by system level modeling and simulation method MuPEN (multi port element network). A resonant accelerometer was constructed and simulated using this model together with MuPEN reusable library. The AC (alternating current) analysis results of MuPEN model agreed well with the results of architect model and the experiment results shown in the existing reference. Therefore, we are convinced that the beam component based on MuPEN method is valid, and MEMS system level design method and related libraries can effectively model and simulate transducers with geometric nonlinear behaviors if appropriate system level components are available. © 2015 Chinese Institute of Electronics.


He Y.,Key Laboratory of Micro Nano Systems for Aerospace | Jiang C.,Key Laboratory of Micro Nano Systems for Aerospace | Wang S.,Key Laboratory of Micro Nano Systems for Aerospace | Hao Y.,Key Laboratory of Micro Nano Systems for Aerospace | And 4 more authors.
ACS Applied Materials and Interfaces | Year: 2014

Understanding the function of nanoscale structure morphology in ice adhesion properties is important in deicing applications. The correlation between ice adhesion and nanowire morphology as well as the corresponding ice shear fracture mechanism are presented for the first time. Ice adhesion on nanowires was measured using a tangential ice-detaching instrument that was developed in-house. Stress analysis was performed using a COMSOL software. Nanowire surface shifted from Wenzel to Cassie transition and Cassie wetting states when the nanowire length was increased. Tangential ice-detaching forces were greater on the hydrophilic surface than those on the hydrophobic surface. Ice-ice internal shear fracture occurred on the ice and force probe contact area at the Wenzel state or on the ice and nanowire contact area at Cassie transition and Cassie state. Different lengths of nanowires caused different wetting states; thus, different fracture areas were formed, which resulted in different tangential ice-detaching forces. This paper presents a new way of tailoring surface ice adhesion via rational design of nanowire morphology with different wetting states. © 2014 American Chemical Society.


Yuan G.,Key Laboratory of Micro Nano Systems for Aerospace | Yuan W.,Key Laboratory of Micro Nano Systems for Aerospace | Liu Y.,Key Laboratory of Micro Nano Systems for Aerospace | Chang H.,Key Laboratory of Micro Nano Systems for Aerospace
Key Engineering Materials | Year: 2013

In order to test the dynamic performance of MEMS devices accurately, the laser Doppler vibrometer was adopted to test the frequency characteristics and surface vibration of the MEMS scanning mirror. The measuring formulas of the object motion velocity and displacement were derived. A kind of MEMS scanning mirror was tested using the established optical testing system. The measurement results show that the resonance frequency characteristic and the transient response characteristic is 269Hz and 60ms respectively which are consistent with the theoretical analysis. The method has significant reference value to the application of the laser Doppler technique. © 2013 Trans Tech Publications Ltd, Switzerland.


Liu Y.,Key Laboratory of Micro Nano Systems for Aerospace | Yuan W.,Key Laboratory of Micro Nano Systems for Aerospace | Qiao D.,Key Laboratory of Micro Nano Systems for Aerospace | Shi L.,Key Laboratory of Micro Nano Systems for Aerospace | Guo X.,Key Laboratory of Micro Nano Systems for Aerospace
Chinese Optics Letters | Year: 2013

The design of a two-dimensional (2D) microscanner actuated electrostatically is presented, and a silicon-on-insulator (SOI) micromachining process is utilized to fabricate the sample. The microscanner can oscillate at inherent frequencies of 1146 and 360 Hz around two rotational axes, generating maximum twisting angles of ±10° and ±5.3° under two 10-V square waves, respectively. A monochromatic laser projection system based on Lissajous pattern is demonstrated using the developed microscanner, revealing an image resolution of 168×56 at 20 frames per second. © 2013 Chinese Optics Letters.


Xie J.,Northwestern Polytechnical University | Xie J.,Key Laboratory of Micro Nano Systems for Aerospace | Song M.,Northwestern Polytechnical University | Song M.,Key Laboratory of Micro Nano Systems for Aerospace | And 2 more authors.
8th Annual IEEE International Conference on Nano/Micro Engineered and Molecular Systems, IEEE NEMS 2013 | Year: 2013

This paper provides an enhanced inertial mass SOI MEMS process for the fabrication of a high sensitivity micromachined accelerometer. In the proposed process, the handle layer of the SOI wafer is used as an enhanced inertial mass, in this way, the inertial mass of the accelerometer can increase 5-15 times. Therefore, the sensitivity of the MEMS accelerometer can be significantly increased. In this paper, an in-plane single-axis accelerometer is designed firstly. And then, the accelerometer is fabricated in a low resistivity SOI wafer with 60μm thickness device layer and 400μm thickness handle layer through the developed enhanced inertial mass SOI MEMS process. The sensitivity of the fabricated MEMS accelerometer is 2.257V/g, the linearity of output is within 0.5%, and the power spectral density of the noises is as low as 6.79uV/√Hz. © 2013 IEEE.


Li X.-Y.,Key Laboratory of Micro Nano Systems for Aerospace | Li G.-T.,Key Laboratory of Micro Nano Systems for Aerospace | Ren S.,Key Laboratory of Micro Nano Systems for Aerospace | Qiao D.-Y.,Key Laboratory of Micro Nano Systems for Aerospace
Microsystem Technologies | Year: 2013

In this paper, in order to avoid the voids during deep trench isolation, an inverted trapezium shaped trench is proposed which is beneficial to polysilicon refill since the top opening size is larger than that of the bottom. An optimized micromachining process is used and an inverted trapezium shaped trench is achieved by isotropic etching. On the other hand, for the filling effect, the completely smooth transition curve type trench is better than the trench with sharp corners. Compared with the linear trench, the completely smooth transition curve type trench can improve the strength of mechanical connection. Through combining the novel trench design with the optimization of trench design, a deep trench without voids can be guaranteed. A void-free deep isolation trench is finally realized which enables the electrical isolation between two movable microstructures or between a movable and a fixed microstructure. © 2012 Springer-Verlag Berlin Heidelberg.


Yu Y.,Key Laboratory of Micro Nano Systems for Aerospace | Yu Y.,Northwestern Polytechnical University | Yuan W.,Key Laboratory of Micro Nano Systems for Aerospace | Yuan W.,Northwestern Polytechnical University | And 2 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

The marriage of optics and MEMS has resulted in a new category of optical devices and systems that have unprecedented advantages compared with their traditional counterparts. As an important spatial light modulating technology, diffractive optical MEMS obtains a wide variety of successful commercial applications, e.g. projection displays, optical communication and spectral analysis, due to its features of highly compact, low-cost, IC-compatible, excellent performance, and providing possibilities for developing totally new, yet smart devices and systems. Three most successful MEMS diffraction gratings (GLVs, Polychromator and DMDs) are briefly introduced and their potential applications are analyzed. Then, three different MEMS tunable gratings developed by our group, named as micro programmable blazed gratings (μPBGs) and micro pitch-tunable gratings (μPTGs) working in either digital or analog mode, are demonstrated. The strategies to largely enhance the maximum blazed angle and grating period are described. Some preliminary application explorations based on the developed grating devices are also shown. For our ongoing research focus, we will further improve the device performance to meet the engineering application requirements. © 2015 SPIE.

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