Papers by Keyword: Semiconductor Sensors

Abstract: Portable breath acetone sensor has great potential in diabetes diagnosis for acetone is a selective breath maker for diabetes. In this paper, we propose a multilayer semiconductor sensor for acetone gas sensing. Device is designed with stress adjustment layer, support layer, metal layer, insulator and sensing film. Simulation is performed, electrothermal and thermomechanical analyses demonstrate that this device has good performance in power consumption and thermomechanical reliability.

Abstract: The increasing fresh water deficiency due to environmental pollution demands accurate, reliable and highly sensitive sensors for online monitoring of water pollution. Solid state sensors are helpful for fabricating and implementing low cost wireless sensors for monitoring of pollution. In water pollution determination, the measurement of pH plays an important role. Among the semiconductor sensitive materials RuO₂ shows good sensitivity to hydrogen ions, high accuracy and resistance to interferences caused by other dissolved ions. In this work, thick film RuO₂ based pH sensitive electrodes are fabricated by screen printing. The sensors were characterized by electromotive force measurements, SEM, optical microscopy and EDS analysis. The effects of sheet resistivity of the material and storage conditions are discussed. The sensor exhibits a sensitivity of 60 mV/pH in wide pH range of 2 to 10. The obtained response was very close to the theoretical Nernstian behavior. The best performance was attained for a sensor fabricated from 10 kΩ/sq. thick film paste and stored at water for 25 days.

Abstract: Animal facilities produce large amounts of harmful gases, and many of them have a pungent odor such as ammonia, hydrogen sulfide and other malodorous gases. The malodorous gases generated by animal house not only affect the health of people and livestock but also pollute the air. The detection of the malodorous gases can effectively improve efficiency of livestock production and reduce environmental pollution. More and more gas detection method is applied to the detection of the malodorous gases generated by animal house. This paper summarizes contact sensors for monitoring of malodorous gases in animal house recently, including semiconductor sensors electrochemical sensors and electronic nose. The basic principle and the characteristics of these methods were illustrated and the applications on the detection of malodorous gases in animal house were described. Meanwhile, the researches of malodorous gases monitoring for livestock production applied contact sensors were listed. The status quo and future development of the contact sensors for malodorous gases generated by animal house were summarized.

Abstract: Recently, application of semiconductor sensors has widely spreaded into various industries becasuse those have several merits like easy miniaturization and batch production etc. But external conditions such as thermal and repetitive load have a bad effect on sensors’s lifetime. Therefore, lots of studies related with the fatigue of microelectromechnical systems (MEMS) have been conducted. Especially, this paper was focused on fatigue life of aluminum interconnect in the supporting structure of sensor under cyclic thermal load and on the approximation equation defining the critical temperature to ensure required operating life using FEM simulation.