基于电容读出的非制冷红外探测器

介绍了一种基于标准硅工艺的电容读出式微悬臂梁非制冷红外探测器的设计、制作以及集成读出电路的设计。该探测器用于探测室温下物体的红外辐射,其响应波长为8～12 μm 。由于氮化硅和铝的热膨胀系数相差很大,用这两种材料的薄膜做成的双材料微悬臂梁在红外辐射下会发生弯曲,微悬臂梁和衬底形成一个可变电容,通过检测电容的变化来反映微悬臂梁的弯曲,从而可以探测红外辐射的情况。采用和探测器集成的CMOS读出电路对探测器信号进行读取,微悬臂梁的电容灵敏度可达2.5 fF/K,温度分辨率为0.1 K。     

一种新型非致冷红外探测器

介绍一种基于标准硅工艺、采用电容读出方式微悬臂梁非制冷红外探测器的设计、制作及性能测试。用这两种热膨胀系数相差很大材料（氮化硅和铝）的薄膜做成的双材料微悬臂梁在红外辐射下，温度升高并发生弯曲。通过检测微悬臂梁和衬底形成的一个可变电容变化可以得知微悬臂梁的弯曲情况，从而可以探测红外辐射的信息。利用外部测试设备对单元探测器进行测试表明微悬臂梁对红外辐射有很高的响应。     

Modelling a micro-cantilever vibrating in vacuum,gas or liquid under thermal base excitation

The dynamic behaviour of a micro-cantilever that is transversely excited at its base is investigated in this paper. The base actuation is provided by thermal cycles via taking the advantage of thermal expansion. The Euler–Bernoulli equation along with corresponding boundary conditions is used to model the continuous cantilever beam. The resultant boundary value problem takes into account the thermal expansion and stiffness of the actuator at the base as well as the effect of the surrounding gas or liquid. A closed-form analytical model is developed to compute natural frequencies, mode shapes, and harmonic response of the vibrating cantilever, in addition to an integral function for quality factor. The model is validated via a finite element (FE) analysis using ANSYS commercial package. This validation shows that the proposed model can properly predict the cantilever's vibrating behaviour.     

A Novel Sensor for Detecting the Vibration

The micro-cantilever beamwith a twin long period optic fiber grating sensitive to the strain and the vibration is designed to use as the sensor head. The micro--displacement of wavelength caused by strain or vibration is amplified in the system. Special cladding material is used to eliminate the interference brougth about the temperature. The designing structure is enabled to detect the micro--information.     

Design and fabrication of electrostatic micro-cantilever array as audible frequency generator

In assistive technologies involving voice communication, an audio signal with specific shape is needed. In this regard, the design and fabrication of an electrostatic cantilever array is proposed. An array of four metallic micro-cantilevers with dimensions 650 μm × 200 μm × 0.3 μm is fabricated on the silicon substrate. The working principle is based on the electrostatic effect generated due to a conductive path applied between the electrodes. The results are taken from zinc oxide (ZnO) piezoelectric thin film that allows making contact with the vibrating cantilevers on a specified applied input impulse signals. The results demonstrated the switching action of the cantilevers that depends on the polarity of the input pulses. The results obtained are compared with the FEM based (COMSOL Multiphysics) model that is designed and analyzed prior to the experiment. Further, the experimental results showed a good agreement with the predicted values calculated by the simulated model for the input impulse signal applied synchronously to all the micro-cantilevers. However, for asynchronous actuation mode, the result of the as-fabricated device showed a variation than the simulated results. The vibrations are generated periodically from all the cantilevers and the output shows the resultant signals that are very much in the audible frequency range.     

An iterative method for nonlinear dynamical system of an electrostatically actuated micro-cantilever

This study proposes an iterative method, in which all iterations are linear, for solving the nonlinear dynamical system of an electrostatically actuated micro-cantilever in MEMS. The presented method is further improved, so that the CPU time needed is significantly reduced. This method provides solutions in excellent agreement with numerical ones.