Sensitive detection of infrared photons using a high-Q microcantilever

A new approach based on microcantilevers is presented to detect infrared photons with high sensitivity. Infrared photons are measured by monitoring the amplitude change of a vibrating microcantilever under light pressure force.The irradiating light is modulated into sinusoidal and pulsed waves,and to be in-phase and anti-phase with the cantilever driving signal.A linear relationship between the amplitude change of the cantilever and the light power distributing on the cantilever was observed.Under a vacuum of 10^-4 Pa,an infrared light power of 7.4 nW was detected with the cantilever.The in-phase and anti-phase modulation to the cantilever vibration using a pulsed light results in an enhanced response of the cantilever.     

基于MEMS VOA阵列的红外场景生成器

针对动态半实物仿真系统的需求,提出了一种新颖的基于微机电系统(MEMS)技术的红外场景生成器。研究了可变光衰减器(VOA)阵列组成红外场景生成器的工作原理和器件结构,提出了新型串联双向折叠梁结构和阵列布局方案,为实现大规模阵列的红外场景生成器奠定基础。     

用于水下金属探测成像的压电式微机械超声波换能器

为满足目前对水下金属、蛙人等检测的应用需要,设计一种用于水下金属探测成像的压电式微机械超声换能器。在该结构中,在顶部电极和下电级之间插入AlN层,用于发射和接收超声。当测试距离达到10 m以上就可以满足实际应用需求,而该换能器经过实验得出最远的测试距离为12.8 m,且在12.8 m处测试值与理论值误差仅为0.67 cm,完全可以达到实际检测需要。在一个标准大气压下,利用微系统激光分析仪MSA400对该传感器进行膜位移测量,其测量值为0.28μm,与理论结果误差为1%。并且详细介绍该传感器的工艺实现过程。利用该传感器实现二维水下超声成像,证明水下存在金属矩形物体。该实验有利于水下超声成像系统的建立。     

基于SiP技术的VCSEL阵列微系统封装

针对半实物仿真系统的需求,基于系统级封装技术提出了一款由垂直腔面发射激光器(VCSEL)激光器阵列、激光器驱动芯片、电源芯片等组成的微系统,并介绍了基于微机电系统微纳加工技术的VCSEL激光器阵列的制造工艺流程.该激光器的封装方法具有集成度高、可靠性高等特点,相比于其他驱动及封装方法大大提高了驱动效率和空间利用率,因此在光学成像、通信、互联等领域具有广泛应用前景,为实现半实物仿真中激光成像发生器奠定了基础.     

基于微悬臂梁的高灵敏红外光子探测

提出一种基于微悬臂梁的具有较高灵敏度的新型红外光子探测方法。该方法通过测量振动悬臂梁在光压作用下振幅的变化量来探测红外光子。实验中,将红外辐射光调制成正弦型或方波脉冲,并与微悬臂梁的激励信号保持同相或反相。实验结果表明,微悬臂梁振幅的改变量与红外光功率之间存在线性关系,并在10^-4 Pa的真空环境中最小可以探测到7.4 nW的红外光功率,另外还发现,方波脉冲调制光会增大微悬臂梁的振幅响应。     

CAN总线通信在掘进机断面成形智能控制系统的应用

为实现对掘进机断面成形的智能化、精准化、实时化控制,在对掘进机巷道断面成形基本理论包括理想掘进轨迹分析的基础上,提出基于CAN总线通信技术实现系统传感器和控制器之间的高质量通信,为保证巷道成形质量和效率奠定基础;同时根据控制需求完成了相应传感器的选型;并基于Matlab软件对智能控制系统的控制效果和CAN总线通信技术的通信质量进行验证。     

基于SiP技术的VCSEL阵列微系统封装

针对半实物仿真系统的需求,基于系统级封装技术提出了一款由垂直腔面发射激光器(VCSEL)激光器阵列、激光器驱动芯片、电源芯片等组成的微系统,并介绍了基于微机电系统微纳加工技术的VCSEL激光器阵列的制造工艺流程.该激光器的封装方法具有集成度高、可靠性高等特点,相比于其他驱动及封装方法大大提高了驱动效率和空间利用率,因此在光学成像、通信、互联等领域具有广泛应用前景,为实现半实物仿真中激光成像发生器奠定了基础.     

射频MEMS封装振荡器的稳定性研究

文章介绍了一种由MEMS圆盘谐振器和低噪声反馈电路构成的射频振荡器。MEMS谐振器具备高Q值,使得振荡器表现出良好的频率稳定性和低相位噪声。采用低成本的金锡键合工艺对双端口谐振器封装后,进一步提升了频率稳定性。低噪声电路由两级放大组成,在提供足够增益的情况下,提升了相位噪声性能。之后测试得到的相位噪声分别是在1 kHz 频偏处为-96 dBc/Hz,噪底 -128 dBc/Hz 。中期稳定性和阿伦方差的测试结果分别为±4 ppm和10 ppb。这些结果均表明,该振荡器在新一代无线通信中有广阔的应用前景。     

沉积、退火条件以及刻蚀液对PECVD氮化硅薄膜湿法刻蚀速率的影响

The influence of deposition, annealing conditions, and etchants on the wet etch rate of plasma enhanced chemical vapor deposition （PECVD） silicon nitride thin film is studied. The deposition source gas flow rate and annealing temperature were varied to decrease the etch rate of SiNx：H by HF solution. A low etch rate was achieved by increasing the SiH4 gas flow rate or annealing temperature, or decreasing the NH3 and N2 gas flow rate. Concentrated, buffered, and dilute hydrofluoric acid were utilized as etchants for Sit2 and SiNx：H. A high etching selectivity of Sit2 over SiNx：H was obtained using highly concentrated buffered HE     

Cantilever with immobilized antibody for liver cancer biomarker detection

A novel cantilever array-based bio-sensor was batch-fabricated with IC compatible MEMS technology for precise liver cancer bio-marker detection. A micro-cavity was designed in the free end of the cantilever for local antibody-immobilization, thus the adsorption of the cancer biomarker takes place only in the local region of the cantilever instead of the whole lever, and the effect of adsorption-induced k variation can be dramatically reduced. These structural features offer several advantages: high sensitivity, high throughput, high mass detection accuracy, and a portable system. In addition, an analytical model has been established to eliminate the effect of the adsorption-induced lever stiffness change and has been applied to the precise mass detection of the cancer biomarker AFP; the experimentally detected AFP antigen mass by the sensor (7.6 pg/mL) is quite close to the calculated one (5.5 pg/mL), two orders of magnitude better than those of the fully antibody-immobilized cantilever sensor. These approaches can promote real applications of the cantilever sensors in cancer diagnosis.