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Over the past few years, microelectromechanical system (MEMS) based on-chip resonators have shown significant potential for sensing and high frequency signal processing applications. This is due to their excellent features like small size, large frequency-quality factor product, low power consumption, low cost batch fabrication, and integrability with CMOS IC technology. Radio frequency communication circuits like reference oscillators, filters, and mixers based on such MEMS resonators can be utilized for meeting the increasing count of RF components likely to be demanded by the next generation multi-band/multi-mode wireless devices. MEMS resonators can provide a feasible alternative to the present day well established quartz crystal technology that is riddled with major drawbacks like relatively large size, high cost, and low compatibility with IC chips. This article presents a survey of the developments in this field of resonant MEMS structures with detailed enumeration on the various micromechanical resonator types, modes of vibration, equivalent mechanical and electrical models, materials and technologies used for fabrication, and the application of the resonators for implementing oscillators and filters. These are followed by a discussion on the challenges for RF MEMS technology in comparison to quartz crystal technology; like high precision, stability, reliability, need for hermetic packaging etc. which remain to be addressed for enabling the inclusion of micromechanical resonators into tomorrow's highly integrated communication systems.

Microelectromechanical system (MEMS) based on-chip resonators offer great potential for sensing and high frequency signal processing applications due to their exceptional features like small size, large frequency-quality factor product, integrability with CMOS ICs, low power consumption etc. This work is mainly aimed at the design, modeling, simulation, and fabrication of micromachined polysilicon disk resonators exhibiting radial-contour mode vibrations. A few other bulk mode modified resonator geometries are also being explored. The resonator structures have been designed and simulated in CoventorWare finite-element platform and fabricated by the PolyMUMPs surface micromachining process., Comment: 7 pages, 12 figures

Quantum superposition and entanglement of physical states can be harnessed to solve some problems which are intractable on a classical computer implementing binary logic. Several algorithms have been proposed to utilize the quantum nature of physical states and solve important problems. For example, Shor's quantum algorithm is extremely important in the field of cryptography since it factors large numbers exponentially faster than any known classical algorithm. Another celebrated example is the Grovers quantum algorithm. These algorithms can only be implemented on a quantum computer which operates on quantum bits (qubits). Rudimentary implementations of quantum processor have already been achieved through linear optical components, ion traps, NMR etc. However demonstration of a solid state quantum processor had been elusive till DiCarlo et al demonstrated two qubit algorithms in superconducting quantum processor. Though this has been a significant step, scalable semiconductor based room temperature quantum computing is yet to be found. Such a technology could benefit from the vast experience of the semiconductor industry. Hence, here we present a reconfigurable semiconductor quantum logic device (SQuaLD) which operates on the position and spin degree of freedom of the electrons in the device. Based on a few recent experiments, we believe SQuaLD is experimentally feasible. Moreover, using a well known quantum simulation method, we show that quantum algorithms (such as Deutsch Jozsa, Grover search) as well as universal classical logic operations (such as NAND gate) can be implemented in SQuaLD. Thus, we argue that SQuaLD is a strong candidate for the future quantum logic processor since it also satisfies the DiVincenzo criteria for quantum logic application as well as the five essential characteristics for classical logic applications., Comment: 29 pages, 8 figures, 1 Table