We report the design, fabrication, and test results of a tunable pyroelectric detector with an integrated micromachined Fabry-Perot (FP) filter for gas analysis in the mid-wave infrared (MWIR). The new approach is based on a bulk micromachined Fabry-Perot interferometer with an air cavity, which is electrostatically tuned. Various types of movable reflectors and spring configurations are fabricated to determine the optimum solution with respect to maximum tuning range, low gravity influence on center wavelength, and suitable filter bandwidth. Short and long cavity filters are designed for the spectral ranges of 3 to 4.3 ?m and 3.7 to 5.0 ?m, respectively. The tunable filter is arranged on top of a current mode pyroelectric detector with a flat spectral response. It is shown that the main challenge is to achieve a high finesse in spite of nonperfect parallelism, mirror curvature, and the additional phase shift caused by the Bragg reflectors
We demonstrate for the first time the embedded integration of a Radio Frequency Microelectromechanical Systems (RF-MEMS) capacitive switch for mm-wave integrated circuits in a BiCMOS Back-end-of-line (BEOL). The switch shows state-of-the-art performance parameters. The ¿off¿ to ¿on¿ capacitance ratio is 1:10 providing excellent isolation in the mm-wave frequency range. Insertion loss and isolation are found to fall below 1.65 dB and to exceed 15 dB, respectively, in the frequency range of 60 GHz to 110 GHz. Feasibility of switch integration into single chip RF designs is demonstrated for a dual-band voltage controlled oscillator (VCO). No performance degradation was observed after ten billion hot-switching cycles
A reliable technique for rapid monitoring of critical dimensional and material parameters during the fabrication of microelectromechanical systems (MEMS) is still an open task. Electrical excitation is sometimes simply not possible, or an electrical test does not reveal sufficient information for a complete characterization. In this paper, we present a new approach that employs optical testing of MEMS vibration frequencies. It is not necessary to have electrical connections because we have developed probes with transparent electrodes to excite vibrations electrostatically without contact on the wafer level. Broadbandwidth excitation is applied to detect all relevant resonances interferometrically through the probes in a single broad-band measurement. Peak detection of the resonances results in a measurement vector containing the resonant frequencies. We demonstrate a new method to estimate system parameters by model identification. The analytical models are derived from a general approach based on finite-element analysis. The parameters with uncertainties are finally determined by guaranteed parameter estimation.[2012-0315]
This paper reports design, fabrication and test results of a tunable pyroelectric detector with an integrated micromachined Fabry-Perot (FP) filter for gas analysis in the Mid-Wave Infrared (MWIR). The new approach is based on a bulk micromachined Fabry-Perot interferometer with an air cavity, which is electrostatically tuned. Various types of moveable reflectors and spring configurations have been fabricated to determine the optimum solution with respect to maximum tuning range, low gravity influence on center wavelength and suitable filter bandwidth. Short and long cavity filters were designed for the spectral ranges of 3...4.3 m and 3.7...5.0 m respectively. The tunable filter is arranged on top of a current mode pyroelectric detector with a flat spectral response. It could be shown that the main challenge is to achieve a high finesse in spite of non-perfect parallelism, mirror curvature and additional phase shift caused by the Bragg reflectors
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.