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The development of micro‐electro‐mechanical systems (MEMS) for use in military and consumer electronics necessitates an analysis of MEMS component reliability. The understanding of the reliability characteristics of SCSi within MEMS structures should be improved to advance MEMS applications. Reliability assessments of MEMS technology may be used to conduct virtual qualification of these devices more efficiently. The purpose of this paper is to create a simple, inexpensive test methodology to use the dynamic fracture strength of a MEMS device to predict its reliability, and to verify this method through experimentation.

The dynamic fracture strength of single crystal silicon (SCSi) was used to model MEMS devices subjected to high shock loading. Experimentation with SCSi MEMS structures was performed following the proposed test methodology. A probabilistic distribution for bending of Deep Reactive Ion Etching (DRIE) processed SCSi around the <110> directions was generated as a tool for assessing product reliability.

Post shock test inspections revealed that failures occurred along {111} planes. Additional experiments provided preliminary estimates of the fracture strength for bending of DRIE processed SCSi around the <100> directions in excess of 1.1 GPa.

This paper proposes a test methodology for an efficient method to assess the reliability of processed SCSi based on dynamic fracture strength.

Standardized systems for feeding, gripping, and joining are needed to realize the potential of microsystem and nano‐system technology. This paper describes many several systems that are operating in this area and the applications for the new technology and the parts that can currently be manufactured. These include miniature pneumatic valves, matchstick sized motors and fluidic pumps.

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.

A frequency tunable half‐wave resonator at 3 GHz is presented with a microelectromechanical systems (MEMS) variable capacitor as the tuning element. The capacitor is fabricated using the multi‐user MEMS process (MUMPs) technology provided by JDS/Cronos, and transferred to an alumina substrate by an in‐house developed flip‐chip process. This capacitor is electrostatically actuated. The resulting C‐V response is linear with a slope of 0.05 pF/V for a wide range of actuation voltages. The MEMS device has a capacitance ratio of 3:1 for 0‐70 V bias, with a Q‐factor of 140 measured at 1 GHz. A half‐wave tunable microstrip resonator with bias lines is designed to include this MEMS device, which exhibits linear tuning over 180 MHz (6 percent) centered around 3 GHz with a constant 3 dB bandwidth of 160 MHz over the entire tuning range. The power consumption of the MEMS device was measured to be negligible.

The purpose of this study is to explore the use of smartphone-embedded microelectro-mechanical sensors (MEMS) for accurately estimating rotating machinery speed, crucial for various condition monitoring tasks. Rotating machinery (RM) serves a crucial role in diverse applications, necessitating accurate speed estimation essential for condition monitoring (CM) tasks such as vibration analysis, efficiency evaluation and predictive assessment.

This research explores the utilization of MEMS embedded in smartphones to economically estimate RM speed. A series of experiments were conducted across three test setups, comparing smartphone-based speed estimation to traditional methods. Rigorous testing spanned various dimensions, including scenarios of limited data availability, diverse speed applications and different smartphone placements on RM surfaces.

The methodology demonstrated exceptional performance across low and high-speed contexts. Smartphones-MEMS accurately estimated speed regardless of their placement on surfaces like metal and fiber, presenting promising outcomes with a mere 6 RPM maximum error. Statistical analysis, using a two-sample t-test, compared smartphone-derived speed outcomes with those from a tachometer and high-quality (HQ) data acquisition system.

The research limitations include the need for further investigation into smartphone sensor calibration and accuracy in extremely high-speed scenarios. Future research could focus on refining these aspects.

The societal impact is substantial, offering cost-effective CM across various industries and encouraging further exploration of MEMS-based vibration monitoring.

This research showcases an innovative approach using smartphone-embedded MEMS for RM speed estimation. The study’s multidimensional testing highlights its originality in addressing scenarios with limited data and varied speed applications.

This paper aims to present design and characterization of a micrograsping system which is capable of safely grasping micro‐objects.

The proposed micrograsping system consists of novel MEMS based microgripper integrated with capacitive contact sensor (fabricated in standard micromachining process SOI‐MUMPs), sense electronics, a controller, high voltage actuation circuit and graphical user interface.

Due to the improvement in the lateral comb‐drive design, the actuator requires low actuation voltages in the range of 0‐45 V. This requires a simple and low power actuation circuitry. Capacitive feedback control mechanism is used in the sensor to detect the contact between the jaws and micro‐object while providing high values of the capacitance.

The designed sense electronics can sense the capacitance ranging from 0‐330 fF. Due to the availability of integrated contact sensor, objects ranging from 54 μm to 70 μm can be gripped safely with the applied maximum force of 220 μN at the tip of the gripper.

The performance of the microgripper, controller algorithm and associated electronics were experimentally quantified through the gripping of 65 μm sized human hair.