MEMS Technology

MEMS on Moon! : MEMS Based Lunar Seismometer to primarily detect Moon quakes . Designed and fabricated at LEOS, Indian Space Research Organisation (ISRO) for Chandrayan 2 lunar Mission. The micro-seismometer is configured to pick low intensity seismic signals on the surface of the Moon.

This paper presents the design and optimisation of a very high quality (Q) factor inductor using MEMS technology for 10 GHz to 20 GHz frequency band. The effects of various parameters of a symmetric inductor structure on the Q-factor and inductance are thoroughly analysed. The inductor has been designed on silicon-on-sapphire (SOS) substrate because it offers superior characteristics of low

Great advancements in the broad field of the seismic monitoring have been achieved in the last decades mainly because of the technical advancement of the instrumentation. Also the seismic monitoring applications greatly developed, mainly since the 1990s owing to the Micro Electro-Mechanical Systems (MEMS) technology. In this short review we outline the applications of the MEMS technology in various sectors of broad field of seismology, distinguishing three main areas of interest and summarizing the state of the art and the most recent progresses.

MEMS (Micro Electro-Mechanical Systems) sensors enable a vast range of applications: among others, the use of MEMS accelerometers for seismology related applications has been emerging considerably in the last decade. In this paper, we provide a comprehensive review of the capacitive MEMS accelerometers: from the physical functioning principles, to the details of the technical precautions, and to the manufacturing procedures. We introduce the applications within seismology and earth sciences related disciplines, namely: earthquake observation and seismological studies, seismic surveying and imaging, structural health monitoring of buildings. Moreover, we describe how the use of the miniaturized technologies is revolutionizing these fields and we present some cutting edge applications that, in the very last years, are taking advantage from the use of MEMS sensors, such as rotational seismology and gravity measurements. In a ten-year outlook, the capability of MEMS sensors will certainly improve through the optimization of existing technologies, the development of new materials, and the implementation of innovative production processes. In particular, the next generation of MEMS seismometers could be capable of reaching a noise floor under the lower seismic noise (few tenths of ng/ √ Hz) and expanding the bandwidth towards lower frequencies (∼0.01 Hz).

In a technological spin-off, initial and further business development is a two-stage challenge of survival and growth. Spin-offs’ business development relies on the design and renewal of an adequate business model, effective open innovation, and advanced knowledge management. This study describes the initial and further business development of a successful spin-off, MEMS&Co, through a longitudinal case study. The business model benefited from specific revenue/investments streams from clients and was subsequently supplemented by new business models in novel applications. Open innovation offered a unique outside-in process from universities, suppliers, and research centres and then transformed into an advanced new process. Knowledge management focused on cross-technical knowledge modularity and subsequently on knowledge recombination.

Abstract: SAW devices have become increasingly important in implementing sensors, chemical and biological warfare agent detectors, resonators and wireless applications as a filter. These types of device can be implemented with micro-electro-mechanical systems (MEMS) to ...

This paper investigates the design and modelling of an integrated device for acoustic resonance spectroscopy (ARS). Miniaturisation of such platforms can be achieved using MEMS technology thereby enabling scaling of device dimensions to investigate smaller specimens while simultaneously operating at higher frequencies. We propose an integrated device where the transducers are mounted in close proximity with the specimen to be analysed (e.g. by integrating ultrasound transducers within a microfluidic channel). A finite element (FE) model and a simplified analytical model have been constructed to predict the acoustic response of a sample embedded in such a device configuration. A FE simulation is performed in COMSOL by embedding the piezoelectric transducers in representative fluid media. Resonant frequencies associated with the measurement can be extracted from this data. The response of various media modelled through FEA matches with analytical predictions for a range of biological media. A variety of biological media may be identified by using the measured resonant frequencies as a signature of relevant physical characteristics. The paper establishes the modelling basis of an integrated acoustic resonant spectrometer that is then applied to examine the impact of geometrical scaling on system resolution.

The patent summarizes results of investigation of high-sensitivity MEMS pressure sensor based on a circuit containing both active and passive stress-sensitive elements: a differential amplifier utilizing two n-p-n piezotransistors and for p-type piezoresistors. A comparative analysis of a sensor utilizing this circuit with a pressure sensor based on traditional piezoresistive Wheatstone bridge and built on the same mechanical part is provided. MEMS pressure sensor with the differential amplifier (PSDA) has sensitivity, which exceeded the sensitivity of the element with piezoresistive Wheatstone bridge (PSWB)

In the fast growth context of micro-electromechanical systems (MEMS) applications, an important improvement of power supplies "power-to-weight" ratio can be obtained through the integration of magnetic storage elements with their associated electronic environment. These components are usually used to transfer and store high energy densities with high magnetic flux. But up until now, integrated devices with these inductive elements were

Research of a highly sensitive MEMS pressure based on the operation of differential amplifier electrical circuit with pressure sensitive active (BJT n-p-n transistor) and passive (p-type resistor) elements are carried out. A comparative analysis is carried out with respect to analogues on the piezoresistive Wheatstone bridge.

We propose the active control of effective stiffness, damping, and mass of MEMS by applying feedback forces that are proportional to displacement, velocity, and acceleration of its proof mass. Such control in performance is important due to the systemic variation in performance caused by process variations, packaging stresses, thermal drift, energy losses, and noise sources. Prior efforts by others have used feedback forces based on position or velocity to modify bandwidth, frequency, quality factor, and the sensitivity of resonators. What is different about our study is that it explores comprehensive control over the effective mass, damping, and stiffness simultaneously. Electrical emulations of mass, damping, and stiffness may be positive or negative, and they can be larger than their purely mechanical counterparts. We provide an analytical derivation for steady-state analysis numerical results for transient analysis. Our steady-state analysis includes signal delay, and transient simulations include both delay and noise. We find that changes in effective mass and stiffness can be increased by an order of magnitude, and damping can be increased by three orders of magnitude.

For small pressure transducer into an electrical signal. Summary of the utility model is that the integral element is formed on a chip having an epitaxial layer made of silicon n-type conductivity, and a substrate made of silicon p + -type conduction membrane and includes roadway and pressure measurement circuit further comprises a temperature sensor formed directly in the thickened part of the membrane sensitive element in the form of three series-connected aluminum metallized tracks isolated diodes created by planar t hnologii as a pn-transition structure "collector-base", wherein the region of "collector" diode formed of silicon n + -type conductivity region "base" of the diode is formed of a silicon p-type conductivity to each area individually summed up aluminum metallized track aluminum metallized pads, diodes are isolated from each other by forming the dividing regions formed of a silicon p + -type conductivity in the epitaxial region where the dividing area is served smallest shy potential - "earth". The technical result: provision of temperature measurement capabilities directly into the volume of the sensitive element.

Polymers, such as poly
methyl methacrylate
PMMA, are important structural materials for microsystems because of their excellent mechanical properties; however, they suffer from severe problems of adhesion, friction, and wear B. Bhushan, J. N. Israelachvili, and U. Landman, Nature

London 374, 607
1995. We report a simple process of O2 plasma treatment on a PMMA film, followed by overcoating with an ultrathin layer of perfluoropolyether
PFPE which improved tribological performance of the film. O2 plasma on PMMA film has formed unique wavy nanotextured surface and increased the hardness and the elastic modulus of the film, which, together with the nanolurbication by PFPE, has increased the wear life of PMMA film by more than five orders of magnitude. © 2008 American Institute of Physics. DOI: 10.1063/1.3062847

Pressure Sensors are one among the widely used micro sensors. The application of MEMS to the measurement of pressure is a mature application of micro machined silicon mechanical sensors. To it advancements, the self powered sensor is more desirable one without compromising the sensitivity as well as to enhance energy scavenging credibility at the same conditions. Now piezoelectric materials are being used to harvest ambient energy. In this paper the circular shaped diaphragm based sensor has been designed and simulated to explore the energy generation capability as well as the sensitivity of the sensor using finite element software INTELLISUITE 8.6. The analysis shows that the deflection of the diaphragm is in a linear relationship with pressure applied. Also variation of the thickness of the diaphragm as well as the piezoelectric layer is done to study its effect on the performance of MEMS piezoelectric pressure sensor.
Keywords- Intellisuite; Energy Harvestingy; MEMS ; Piezoelectric pressure sensor ;

The article translated from Russian to English on pp. 373-376 (please, look down). The paper presents the design of a silicon pressure sensitive elements (SEP) with stops. Stops are providing resistance of overload pressure. The advantage of stops was proved. The required size between the membrane and stops for working displacement of the membrane was determined. The results of researching parameters for samples with increased strength have been described. SEP is working in the range from 1.6 to 25.0 kPa. Elements can increase overload strength in 5X times compared standard design SEP without stops.

Abstract Fuel cells have potentially higher energy density than batteries and promise a significant increase in power availability for portable electronics. However, developing a fuel cell system for portable electronics presents several engineering challenges. To achieve ...

The report presents the results of modeling a highly sensitive element of the pressure sensor, which made in the form of a MEMS silicon chip. The circuitry and technological aspects of building a thermally stable system based on the functioning of the electrical circuit of a differential amplifier with negative feedback have been developed. A comparative analysis of the strain sensitivity relative to analogues with the electrical circuit of the Wheatstone resistive bridge is carried out.

The paper describes modeling of high-sensitivity MEMS
pressure sensor based on a circuit containing both active and passive
stress-sensitive elements: a differential amplifier utilizing two
n-p-n transistors and four p-type piezoresistors. The analysis on the
basis of the developed mathematical model for a pressure sensor
with traditional piezoresistive Wheatstone bridge and theoretical
conclusions regarding the change in the electrical parameters of a
bipolar transistor under the influence of deformation was carried
out.

... 8. ACKNOWLEDGEMENTS This research has been made possible by the interest and support provided by the Gennum Corporation of Burlington, Ontario. ... 89, No. 5, May 2001, pp. 586-601. [4] Sazzadur Chowdhury, M. Ahmadi, WC Miller, “A ... 938-941. [5] N. Yazdi, A. Mason, K ...

We propose the active control of effective stiffness, damping, and mass of MEMS by applying feedback forces that are proportional to displacement, velocity, and acceleration of its proof mass. Such control in performance is important due to the systemic variation in performance caused by process variations, packaging stresses, thermal drift, energy losses, and noise sources. Prior efforts by others have used feedback forces based on position or velocity to modify bandwidth, frequency, quality factor, and the sensitivity of resonators. What is different about our study is that it explores comprehensive control over the effective mass, damping, and stiffness simultaneously. Electrical emulations of mass, damping, and stiffness may be positive or negative, and they can be larger than their purely mechanical counterparts. We provide an analytical derivation for steady-state analysis numerical results for transient analysis. Our steady-state analysis includes signal delay, and transient simulations include both delay and noise. We find that changes in effective mass and stiffness can be increased by an order of magnitude, and damping can be increased by three orders of magnitude.