A microphone is a transducer that converts acoustic energy into electrical energy. Microphones are widely used in voice communications devices, hearing aids, surveillance and military aims, ultrasonic and acoustic distinction under water, and noise and vibration control (Ma et al. 2002). Micromachining technology has been used to design and fabricate various silicon microphones. Among them, the...

Stretchable capacitive devices are instrumental for new-generation multifunctional haptic technologies particularly suited for soft robotics and electronic skin applications. A majority of elongating soft electronics still rely on silicone for building devices or sensors by multiple-step replication. In this study, fabrication of a reliable elongating parallel-plate capacitive touch sensor, usi...

An electrostatic-spray ionization (ESTASI) method has been used for mass spectrometry (MS) analysis of samples deposited in or on an insulating substrate. The ionization is induced by a capacitive coupling between an electrode and the sample. In practice, a metallic electrode is placed close to but not in direct contact with the sample. Upon application of a high voltage pulse to the electrode,...

We describe resonant capacitive MEMS transducers developed for use as acoustic emission detectors, fabricated in the commercial three-layer polysilicon surface micromachining process (MUMPs). The 1-cm square device contains six independent transducers in the frequency range between 100 kHz and 500 kHz, and a seventh transducer at 1 MHz. Each transducer is a parallel plate capacitor with one pla...

Conventional capacitive MEMS transducer designs feature a single flexible diaphragm acting as a moving plate and an electrode patterned on the substrate acting as a stationary plate. Such devices generally function adequately as receivers. However, such devices show poor transmission efficiency when the gap dimension is limited by the manufacturing process and when the diaphragm would suffer “p...

This paper describes the design and testing method of a micro robotic detector. The detector was implemented with capacitors. The chip employs the concept of an ultrasonic rangefinder. The fly can detect and locate objects in all directions easily. The micro robot needs to have this capability. In order to implement this, detectors was built to resemble a “soccer ball”. A robust fabrication pro...

Theoretical limits for the capacitance density of integrated capacitors with combined lateral and vertical field components are derived. These limits are used to investigate the efficiency of various capacitive structures such as lateral flux and quasifractal capacitors. This study leads to two new capacitor structures with high lateral-field efficiencies. These new capacitors demonstrate large...

The grain level in a silo is commercially important. In this work, a novel method is presented to detect the grain level in a silo. Existing methods are generally based on approximations, due to grain dust in the silo. The method proposed here eliminates the effect of grain dust and gives the accurate reading of the grain level. The method is based on the measurements of capacitances of paralle...

This work presents a CMOS (complementary metal oxide semiconductor) micromachined capacitive differential flow sensor for respiratory monitoring. Airflow induces a pressure change on the suspended sensing plate and causes a capacitance change with respect to the electrodes. The microstructure fabricated by post-CMOS metal etch occupies an area of 320 × 230 m and has differential sensing capaci...

Accurate determination of the pull-in, or the collapse voltage is critical in the design process. In this paper an analytical method is presented that provides a more accurate determination of the pull-in voltage for MEMS capacitive devices with clamped square diaphragm. The method incorporates both the linearized modle of the electrostatic force and the nonlinear deflection model of a clamped ...