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Reports the design, fabrication and packaging of a micromachined silicon/Pyrex based chip for the polymerase chain reaction (PCR). The anodic bonding method is used for sealing the chambers of 1μl volume with a Pyrex glass wafer. Platinum resistors on the back of the wafer are used as heaters and temperature sensors. The chip is externally cooled by forced air to achieve rapid temperature cycling. The transparency of the Pyrex makes it possible for using optical readout methods. The packaging is especially designed for easy handling, filling, power connection, temperature regulation and optical readout. The mass production of such silicon reactors could make single‐shot throwaway devices economically viable.

Recent findings from a monitor containing around 1.5 million homes in the Dutch non-profit rental sector show that the improvement of the energy performance of the respective homes is mostly carried out in small steps: single measures per dwelling dominate and deep energy renovations are rare. From the way in which housing providers conceive and implement their portfolio and asset management strategies, the purpose of this paper is to explain for the dominance of the small interventions and investigate the argument for a more concentrated allocation of budget resources.

In total, 12 housing providers with different energy investment policies were selected and interviewed.

Results show that energy investments, as most other investments, must fit in regular investment schemes and have to follow general decision criteria such as the lifespan of the respective building element and the market position of the respective dwelling. As these schemes are limited in budget and time, the room for a more concentrated allocation of budget resources is small.

The number of organisations interviewed is obviously not statistically representative, but gives a good indication of the investment planning practice in the Dutch non-profit housing sector.

Much has been written about the (slow) progress of the energy performance in the housing sector, but not about the more structural organisational forces behind this progress.

Janette Rowland has been appointed marketing services manager of General Hybrid. Based at their facility on Tyneside, and reporting to the general sales manager, Ms Rowland is responsible for all PR, marketing support and promotional activities for General Hybrid worldwide. She joins the company from CSM, a software house, where she held the position of marketing executive.

The purpose of this paper is to demonstrate the influence of material properties and fabrication technique on the performance of an embedded pressure sensor. Based on conducted theoretical analysis a suitable material and technological technique that gave the best behavior of designed sensor was chosen for its fabrication. This is verified on the example of a resonant pressure sensor, designed for operation in the MHz range.

A sensor module is fabricated using the low temperature co‐fired ceramics (LTCC) technology and sputtering technique for electrodes deposition. The module comprises an inductor connected with a variable capacitor formed by the sensor membranes in a parallel LC circuit. An extensive parallel analysis of sensors performance for sensors with thick film (screen‐printed) and thin film (sputtered) electrodes is demonstrated. Mechanical and electrical parameters (Young's modulus and permittivity) of different tape materials that are considered for sensor fabrication are determined at room temperature.

Implementation of the sputtering technique for deposition of the thin film electrodes and usage of tapes with higher elasticity significantly contribute to the increase of the sensor performance (improved sensitivity) compared to designs found in available literature. Experimentally attained results are compared with the ones obtained by analytical calculations achieving good agreement of obtained results.

The improvement of sensor sensitivity by means of evaluation of different tape material and electrode thickness reduction is demonstrated for the first time. The presented results of the sensor equivalent model and the sensor‐antenna system are in good compliance with experimental data determined through measurement.

The main purpose of this paper is to find a simple method to improve the breakdown voltage of BJTs fabricated on SOI.

We have used two‐dimensional device simulation to examine the effect of a collector tub on the collector breakdown of the SOI based BJTs. This method involves creating a collector tub by etching the buried oxide followed by an n‐type implantation on the collector n/n+ junction side.

First, our method reduces the peak electric field at the silicon film‐BOX interface and secondly, the collector‐tub facilitates the collector potential to be absorbed by both collector drift and substrate regions improving the collector breakdown significantly.

An improved breakdown voltage improves the reliability of BJTs on SOI.

Our results show that the BV_CEO of the bipolar transistors with a collector‐tub is enhanced by 2.7 times when compared with a conventional lateral bipolar transistor (LBT) with identical drift region doping. This improvement has an important practical value in the fabrication of SOI‐based LBTs.

This paper aims to describe the fabrication, packaging and testing of a resistive loaded p-channel metal-oxide-semiconductor field-effect transistor-based (MOSFET-based) current mirror-integrated pressure transducer.

Using the concept of piezoresistive effect in a MOSFET, three identical p-channel MOSFETs connected in current mirror configuration have been designed and fabricated using the standard polysilicon gate process and microelectromechanical system (MEMS) techniques for pressure sensing application. The channel length and width of the p-channel MOSFETs are 100 µm and 500 µm, respectively. The MOSFET M1 of the current mirror is the reference transistor that acts as the constant current source. MOSFETs M2 and M3 are the pressure-sensing transistors embedded on the diaphragm near the mid of fixed edge and at the center of the square diaphragm, respectively, to experience both the tensile and compressive stress developed due to externally applied input pressure. A flexible square diaphragm having a length of approximately 1,000 µm and thickness of 50 µm has been realized using deep-reactive ion etching of silicon on the backside of the wafer. Then, the fabricated sensor chip has been diced and mounted on a TO8 header for the testing with pressure.

The experimental result of the pressure sensor chip shows a sensitivity of approximately 0.2162 mV/psi (31.35 mV/MPa) for an input pressure of 0-100 psi. The output response shows a good linearity and very low-pressure hysteresis. In addition, the pressure-sensing structure has been simulated using the parameters of the fabricated pressure sensor and from the simulation result a pressure sensitivity of approximately 0.2283 mV/psi (33.11 mV/MPa) has been observed for input pressure ranging from 0 to 100 psi with a step size of 10 psi. The simulated and experimentally tested pressure sensitivities of the pressure sensor are in close agreement with each other.

This current mirror readout circuit-based MEMS pressure sensor is new and fully compatible to standard CMOS processes and has a promising application in the development CMOS-MEMS-integrated smart sensors.

This article aims to discuss the construction of a system for temperature cycling, where Peltier elements are used as heating or cooling elements. This article describes the results and experiences based on several years of practice in the area of thermo-mechanical reliability of soldered joints on printed boards with SMD components.

The authors discuss the characteristics of the design, the threshold temperatures, dynamic properties of the system and, most importantly, the reliability and the useful life of the Peltier elements. The advantages and disadvantages of the system are mentioned as well as examples of use.

The utilisation of Peltier elements for temperature cycling is possible, but it is important to keep in mind that the reliability of the elements is similar to the reliability of the system, and therefore, it is essential to replace the defective Peltier elements during the cycling.

The construction of system is very simply. It is necessary to ensure the Peltier elements with low dispersion parameters.

The system is very well suited for cycling of printed boards, especially one sided, multi-chip systems, COB systems, flip-chip embedded construction, etc. The system can be used in situations where it is possible to ensure an effective heat transfer and where extremely low temperatures are not required.

The present paper aims to propose a basic current mirror-sensing circuit as an alternative to the traditional Wheatstone bridge circuit for the design and development of high-sensitivity complementary metal oxide semiconductor (CMOS)–microelectromechanical systems (MEMS)-integrated pressure sensors.

This paper investigates a novel current mirror-sensing-based CMOS–MEMS-integrated pressure-sensing structure based on the piezoresistive effect in metal oxide field effect transistor (MOSFET). A resistive loaded n-channel MOSFET-based current mirror pressure-sensing circuitry has been designed using 5-μm CMOS technology. The pressure-sensing structure consists of three identical 10-μm-long and 50-μm-wide n-channel MOSFETs connected in current mirror configuration, with its input transistor as a reference MOSFET and output transistors are the pressure-sensing MOSFETs embedded at the centre and near the fixed edge of a silicon diaphragm measuring 100 × 100 × 2.5 μm. This arrangement of MOSFETs enables the sensor to sense tensile and compressive stresses, developed in the diaphragm under externally applied pressure, with respect to the input reference transistor of the mirror circuit. An analytical model describing the complete behaviour of the integrated pressure sensor has been described. The simulation results of the pressure sensor show high pressure sensitivity and a good agreement with the theoretical model has been observed. A five mask level process flow for the fabrication of the current mirror-sensing-based pressure sensor has also been described. An n-channel MOSFET with aluminium gate was fabricated to verify the fabrication process and obtain its electrical characteristics using process and device simulation software. In addition, an aluminium gate metal-oxide semiconductor (MOS) capacitor was fabricated on a two-inch p-type silicon wafer and its CV characteristic curve was also measured experimentally. Finally, the paper presents a comparative study between the current mirror pressure-sensing circuit with the traditional Wheatstone bridge.

The simulated sensitivities of the pressure-sensing MOSFETs of the current mirror-integrated pressure sensor have been found to be approximately 375 and 410 mV/MPa with respect to the reference transistor, and approximately 785 mV/MPa with respect to each other. The highest pressure sensitivities of a quarter, half and full Wheatstone bridge circuits were found to be approximately 183, 366 and 738 mV/MPa, respectively. These results clearly show that the current mirror pressure-sensing circuit is comparable and better than the traditional Wheatstone bridge circuits.

The concept of using a basic current mirror circuit for sensing tensile and compressive stresses developed in micro-mechanical structures is new, fully compatible to standard CMOS processes and has a promising application in the development of miniaturized integrated micro-sensors and sensor arrays for automobile, medical and industrial applications.

I present and evaluate various explanations for why new workers who were sponsored by oldtimers tend to have better job outcomes (better performance, more satisfaction, and less turnover) than do new workers who were not sponsored.

My evaluations involve searching for evidence that fits (or does not fit) each of the explanations.

The two most popular explanations argue that the job benefits of sponsorship arise because (a) sponsored newcomers have more realistic job expectations than do unsponsored newcomers, or (b) the quality of sponsored newcomers is greater than that of unsponsored newcomers. Unfortunately, these explanations have weak empirical support. A third explanation, largely untested as yet, attributes the performance benefits of sponsorship to social pressures that can arise when someone is sponsored for a job. These pressures include efforts by newcomers to repay the people who sponsored them, efforts by sponsors to assist the newcomers they sponsored after those persons have been hired, and stereotypes among coworkers about the kinds of people who get jobs through sponsors. Although limited as yet, the evidence regarding this new explanation seems promising.

More research on this third explanation for sponsorship effects should be done. Suggestions for how to do such research are reviewed and a relevant experiment is presented.

The ideas and evidence presented here could help employers who want to improve the job outcomes of their new workers. Poor outcomes among such persons are a major problem in many settings.

Although some of my ideas have been mentioned by others, they were not been described in much detail, nor were they tested. My hope is that this chapter will promote new theory and research on the performance benefits of sponsorship, a topic that has been largely ignored in recent years.