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Radio frequency micro- and nanoelectromechanical systems (RF MEMS and RF NEMS) and technologies have a great potential to overcome the constraints of conventional IC technologies in realization of fully integrated transceivers of next generation wireless communications systems. During the last two decades a considerable effort has been made to develop RF MEMS/NEMS resonators so that they could replace conventional bulky off-chip resonators in wireless transceivers. In MEMS, and especially in NEMS resonators, additional noise generating mechanisms exist that are characteristic for structures of small dimensions and mass, and high surface to volume ratio. One such mechanism is the adsorption-desorption (AD) process that generates the resonator frequency (phase) noise. In the first part of this paper a short overview of RFM EMS resonators is given, including comments on the necessary improvements and the direction of future research in this field (especially having in mind the need for NEMS resonators), with the intention to optimize RF MEMS and NEMS components according to requirements of both current and future systems. The main part of the paper presents a comprehensive theory of AD noise in MEMS/NEMS resonators. Apart from having a theoretical significance, the derived models of AD noise in multiple different cases of adsorption are also a useful tool for the design of optimal performance RF MEMS and NEMS resonators. The model of the MEMS/NEMS oscillator phase noise that takes into account the influence of AD noise is presented for the first time.

Radio frequency micro- and nanoelectromechanical systems (RF MEMS and RF NEMS) and technologies have a great potential to overcome the constraints of conventional IC technologies in realization of fully integrated transceivers of next generation wireless communications systems. During the last two decades a considerable effort has been made to develop RF MEMS/NEMS resonators so that they could replace conventional bulky off-chip resonators in wireless transceivers. In MEMS, and especially in NEMS resonators, additional noise generating mechanisms exist that are characteristic for structures of small dimensions and mass, and high surface to volume ratio. One such mechanism is the adsorption-desorption (AD) process that generates the resonator frequency (phase) noise. In the first part of this paper a short overview of RFM EMS resonators is given, including comments on the necessary improvements and the direction of future research in this field (especially having in mind the need for NEMS resonators), with the intention to optimize RF MEMS and NEMS components according to requirements of both current and future systems. The main part of the paper presents a comprehensive theory of AD noise in MEMS/NEMS resonators. Apart from having a theoretical significance, the derived models of AD noise in multiple different cases of adsorption are also a useful tool for the design of optimal performance RF MEMS and NEMS resonators. The model of the MEMS/NEMS oscillator phase noise that takes into account the influence of AD noise is presented for the first time.

In this paper we present the concept of a compact intelligent industrial pressure transmitter developed at the Center of Microelectronic Technologies (CMT), and discuss some of the most important steps in its design process. First the constraints of the design are defined, and then the decisions are made in order to fulfill the design objectives in an optimal way, which is made possible by using the latest available technology. Especially important for this design are mixed signal circuits, and the focus is on the digital-to-analog circuitry that generates the transmitter's analog output signal. Several solutions are considered and compared, and the chosen one is further investigated, including the experimental characterization of the output current error across the operating temperature range. Apart from industrial transmitters, the results of the work can be significant for other kinds of electronic instrumentation.

In this paper we present the concept of a compact intelligent industrial pressure transmitter developed at the Center of Microelectronic Technologies (CMT), and discuss some of the most important steps in its design process. First the constraints of the design are defined, and then the decisions are made in order to fulfill the design objectives in an optimal way, which is made possible by using the latest available technology. Especially important for this design are mixed signal circuits, and the focus is on the digital-to-analog circuitry that generates the transmitter's analog output signal. Several solutions are considered and compared, and the chosen one is further investigated, including the experimental characterization of the output current error across the operating temperature range. Apart from industrial transmitters, the results of the work can be significant for other kinds of electronic instrumentation.

In this paper we present the concept of a compact intelligent industrial pressure transmitter developed at the Center of Microelectronic Technologies (CMT), and discuss some of the most important steps in its design process. First the constraints of the design are defined, and then the decisions are made in order to fulfill the design objectives in an optimal way, which is made possible by using the latest available technology. Especially important for this design are mixed signal circuits, and the focus is on the digital-to-analog circuitry that generates the transmitter's analog output signal. Several solutions are considered and compared, and the chosen one is further investigated, including the experimental characterization of the output current error across the operating temperature range. Apart from industrial transmitters, the results of the work can be significant for other kinds of electronic instrumentation.

In this paper we propose a novel operating principle for thermal vacuum sensor. The sensor considered in this work consists of thermopiles and thermally isolating membrane structure. The operating principle of such sensor would be based on monitoring thermal time constant dependence on pressure. In order to get the most prominent effect, sensor fabricated on SOI wafer is studied. Simulation was performed using 1D analytical model. It is shown that sensors performance could be improved by increasing the number of thermocouples. Apart from that it is demonstrated that performance of such sensor depends also on gas present in the housing so the same device could be also used as a gas type detector.

This paper presents microcantilever fabrication on {100} oriented Si substrate using bulk micromachining technique. Detailed characteristics of convex corner compensation design for {100} oriented beam for two etching solutions: 25 wt. % TMAH and 30 wt. % KOH water solutions at 80 degrees C are given.

In industrial processes, as well as in many other fields from vehicles to healthcare, temperature and pressure are the most common parameters to be measured and monitored. Silicon microelectromechanical (MEMS) piezoresistive pressure sensors are the first and the most successful MEMS sensors, widely used in the industry in various measurement configurations. The inherent temperature dependence of the output signal of such sensors adversely affects their pressure measurement performance. However, it can be utilized for temperature measurement, thus enabling new sensor applications. In this paper a method is presented for temperature measurement using MEMS piezoresistive pressure sensors.

This paper presents an application "IndCalc" for calculation of surface-mounted devices (SMD) inductor parameters, extracted from measured S-parameters. It simplifies characterization and provides reliable procedure for determining SMD inductor's parameters in a wide frequency range up to several GHz. In order to present developed application and its validity, commercially available components in their printed circuit board (PCB) environment are measured using Agilent vector network analyzer E5071B.

In this paper we compared a resistive and capacitive strain gauge in terms of sensitivity and material cost, both printed with deposition material printer using silver nanoparticle ink on a flexible polyimide substrate. The resistive change due to strain was measured with a full Wheatstone bridge and a signal conditioning circuit, while the capacitance change was measured with the HP4194A impedance analyzer. Measured and derived strain gauge factor for resistive sensor was 1.10, and 0.91 for the capacitive sensor.