Novel 2×2 torsion-mirror optical switch arrays are fabricated by using the mixed micromachining based on the surface and bulk silicon microelectronics,then are investigated electromechanically in applied direct a...Novel 2×2 torsion-mirror optical switch arrays are fabricated by using the mixed micromachining based on the surface and bulk silicon microelectronics,then are investigated electromechanically in applied direct and alternating electric fields.When the thickness of the elastic torsion beams suspending the aluminum coated polysilicon micro-mirrors of the switches in the arrays is about 1μm,the electrostatic yielding voltages for driving the mirrors to achieve their ON-state are in the range of 270～290V,and the minimum holding voltages for mirrors ON-state are found as 55V or so.Theoretical analysis manifests that the yielding voltage is more sensitive to beam thickness than other design parameters do about the torsion-mirror switch structures.The lifetime can reach 10 8 times.The estimated shortest switching time of the switches at least lasts for less than 2ms.The force analysis on the two kinds of new fiber self-holding structures integrated monolithically in the chip of the optical switch arrays indicates that the structures can feature self-fixing and self-aligning of optical fibers.展开更多
Spectrometer is an essential and necessary optical element used for measuring the chemical components and content of the matter. The development of miniature spectrometers can be traced back to 1980s. The development ...Spectrometer is an essential and necessary optical element used for measuring the chemical components and content of the matter. The development of miniature spectrometers can be traced back to 1980s. The development state and different manufacturing methods of micro-spectrometers are presented. Finally, we analyze the miniaturization trend of spectrometers. Some groundwork for the scientific research is offered by introducing micro-spectrometers development.展开更多
On account of the multiformity of MEMS devices, it is necessary to integrate with some optical measurement techniques for meeting static and dynamic unit test requirements. In this paper, an automated MEMS test system...On account of the multiformity of MEMS devices, it is necessary to integrate with some optical measurement techniques for meeting static and dynamic unit test requirements. In this paper, an automated MEMS test system is built of some commercially available components and instruments based on virtual instrument technology. The system is integrated with stroboscopic imaging, computer micro-vision, microscopic Mirau phase shifting interferometry, and laser Doppler vibrometer, and is used for the measurement of full-view in-plane and out-of-plane geometric parameters and periodical motions and single spot out-of-plane transient motion. The system configuration and measurement methods are analyzed, and some applications of the measurement of in-plane and out-of-plane dimensions and motions were described. The measurement accuracy of in-plane dimensions and out-of-plane dimensional is better than 0.2 um and 5 nm respectively. The resolution of measuring in-plane and out-of-plane motions is better than 15 nm and 2 nm respectively.展开更多
We aimed to develop a process technology for constructing a carbon-based micro-electromechanical system that does not require a high-temperature and high-energy process. A HOPG （highly oriented pyrolytic graphite） c...We aimed to develop a process technology for constructing a carbon-based micro-electromechanical system that does not require a high-temperature and high-energy process. A HOPG （highly oriented pyrolytic graphite） crystal microsheet was prepared by exfoliation. Cantilevers and doubly clamped beams were patterned using a photoresist. The HOPG microsheet was attached by using a tantalum layer. We fabricated cantilevers and a doubly clamped beam by controlling the thickness of the HOPG microsheet and then measured the first resonance frequency. The measurements suggest a need to improve the stiffness of the beam.展开更多
Thick SU8 microstructures with high aspect ratio and good side wall quality were fabricated by ultraviolet （UV） lithography, and the processing parameters were comprehensively studied. It proves that the adhesion of...Thick SU8 microstructures with high aspect ratio and good side wall quality were fabricated by ultraviolet （UV） lithography, and the processing parameters were comprehensively studied. It proves that the adhesion of SU8 on silicon （Si） substrates is influenced by Si-OH on the surface, and can be improved by the HF treatment. Cracks and de- lamination are caused by large internal stress during fabrication process, and are significantly influenced by soft bake and post-exposure bake processes. The internal stress is reduced by a low post-exposure bake exposure tem- perature of 85 ℃ for 40 rain. A three-step soft bake enhances the reflowing ofSU8 photoresist, and results in uni- form surface and less air bubbles. The vertical side wall is obtained with the optimized exposure dose of 800 mJ/cm2 for the thickness of 160 μm. Using the optimized fabrication process combined with a proper structure design, dense SU8 micro pillars are achieved with the aspect ratio of 10 and the taper angle of 89.86°. Finally, some possible ap- plications of SU8 in micro-electromechanical system （MEMS） device are developed and demonstrated.展开更多
文摘Novel 2×2 torsion-mirror optical switch arrays are fabricated by using the mixed micromachining based on the surface and bulk silicon microelectronics,then are investigated electromechanically in applied direct and alternating electric fields.When the thickness of the elastic torsion beams suspending the aluminum coated polysilicon micro-mirrors of the switches in the arrays is about 1μm,the electrostatic yielding voltages for driving the mirrors to achieve their ON-state are in the range of 270～290V,and the minimum holding voltages for mirrors ON-state are found as 55V or so.Theoretical analysis manifests that the yielding voltage is more sensitive to beam thickness than other design parameters do about the torsion-mirror switch structures.The lifetime can reach 10 8 times.The estimated shortest switching time of the switches at least lasts for less than 2ms.The force analysis on the two kinds of new fiber self-holding structures integrated monolithically in the chip of the optical switch arrays indicates that the structures can feature self-fixing and self-aligning of optical fibers.
文摘Spectrometer is an essential and necessary optical element used for measuring the chemical components and content of the matter. The development of miniature spectrometers can be traced back to 1980s. The development state and different manufacturing methods of micro-spectrometers are presented. Finally, we analyze the miniaturization trend of spectrometers. Some groundwork for the scientific research is offered by introducing micro-spectrometers development.
基金Supported by National Natural Science Foundation of China (No.50505031)Tianjin Municipal Science and Technology Commission(No.043185911)Programfor NewCentury Excellent Talents in University
文摘On account of the multiformity of MEMS devices, it is necessary to integrate with some optical measurement techniques for meeting static and dynamic unit test requirements. In this paper, an automated MEMS test system is built of some commercially available components and instruments based on virtual instrument technology. The system is integrated with stroboscopic imaging, computer micro-vision, microscopic Mirau phase shifting interferometry, and laser Doppler vibrometer, and is used for the measurement of full-view in-plane and out-of-plane geometric parameters and periodical motions and single spot out-of-plane transient motion. The system configuration and measurement methods are analyzed, and some applications of the measurement of in-plane and out-of-plane dimensions and motions were described. The measurement accuracy of in-plane dimensions and out-of-plane dimensional is better than 0.2 um and 5 nm respectively. The resolution of measuring in-plane and out-of-plane motions is better than 15 nm and 2 nm respectively.
文摘We aimed to develop a process technology for constructing a carbon-based micro-electromechanical system that does not require a high-temperature and high-energy process. A HOPG （highly oriented pyrolytic graphite） crystal microsheet was prepared by exfoliation. Cantilevers and doubly clamped beams were patterned using a photoresist. The HOPG microsheet was attached by using a tantalum layer. We fabricated cantilevers and a doubly clamped beam by controlling the thickness of the HOPG microsheet and then measured the first resonance frequency. The measurements suggest a need to improve the stiffness of the beam.
基金supported by the National High Technology Research and Development Program(No.2015AA042603)the Fundamental Research Funds for the Central Universities in China(Nos.106112014CDJZR160001 and 106112015CDJXY120002)
文摘Thick SU8 microstructures with high aspect ratio and good side wall quality were fabricated by ultraviolet （UV） lithography, and the processing parameters were comprehensively studied. It proves that the adhesion of SU8 on silicon （Si） substrates is influenced by Si-OH on the surface, and can be improved by the HF treatment. Cracks and de- lamination are caused by large internal stress during fabrication process, and are significantly influenced by soft bake and post-exposure bake processes. The internal stress is reduced by a low post-exposure bake exposure tem- perature of 85 ℃ for 40 rain. A three-step soft bake enhances the reflowing ofSU8 photoresist, and results in uni- form surface and less air bubbles. The vertical side wall is obtained with the optimized exposure dose of 800 mJ/cm2 for the thickness of 160 μm. Using the optimized fabrication process combined with a proper structure design, dense SU8 micro pillars are achieved with the aspect ratio of 10 and the taper angle of 89.86°. Finally, some possible ap- plications of SU8 in micro-electromechanical system （MEMS） device are developed and demonstrated.
