bluuebunny/crossref_metadata_2025_split huggingface dataset:
Squeeze Film Damping Effects in a Micromachined Tunneling Accelerometer
Authors: da Silva Mark G. , Greiner Ken , Liu Cheng-Hsien , Kenny Thomas W. , Gilbert John R. 
Published: December 2021

Abstract
Attempts at predicting the squeeze film damping (SQFD) effects in MEMS devices have by and large been restricted to the following approaches; analytic [1] or numerical [3–5] modeling of the Reynolds equation, or numerical solutions of incompressible Navier-Stokes (NS) [6] and correcting the Reynolds or incompressible NS for the effects of high Knudsen number [3, 7]. There are key difficulties with these approaches that render them unsuitable or unacceptable for realistic design problems. Recently the development of a hybrid technique called Navier-Stokes-Reynolds (NSR) [8] has shown some promise in addressing some of the key difficulties in previous approaches. In this work we extend the method to a class of devices characterized by nonuniform gaps (e.g. tilting mirrors [2], accelerometers etc.). The micromachined high precision tunneling accelerometer designed at the SMSSL (Stanford University [9]) is one such device. A comparison of the experiments and predictions show quite good agreement over the operating regime of the device.
Thermal Design and Batch Fabrication of Cantilever Probes for Scanning Thermal Microscopy
Authors: Shi Li , Kwon Ohmyoung , Wu Guanghua , Majumdar Arunava 
Published: December 2021

Abstract
Scanning thermal microscopy (SThM) has enabled direct observation of thermal phenomena at the nanometer scale. The superior spatial resolution makes SThM attractive for thermally probing electronic and optoelectronic devices as well as nano-structures. In the past, lack of thermal design of SThM probes led to inaccuracy and artifacts in the thermal images. Based on the knowledge of various tip-sample heat transfer mechanisms, this paper presents a one-dimensional model to estimate the temperature distribution in the probe tip. Based on the model, new thermal probes that have SiO2 tips, SiNx cantilevers, and Pt-Cr thermocouple junctions at the tip ends have been designed and fabricated. The fabrication process consists of only wafer-stage processing steps with more than 100 probes fabricated on a single wafer. The thermal probes have been successfully used for topographical imaging and to measure the intensity profile of a focused laser spot.
A Thermal Cycler Fabricated With Low Temperature, Co-Fired Ceramic Tapes
Authors: Zhong Jihua , Yi Mingqiang , Bau Haim H. 
Published: December 2021

Abstract
A thermal cycler fabricated with low temperature, co-fired, ceramic tapes is described. The monolithic device consisted of a flow conduit, a resistor (Joule) heater, a thermistor, and conductors. A microprocessor was used to control the device’s temperature according to a pre-programmed temperature protocol. The device’s thermal performance was modeled, and the theoretical predictions were compared with experimental observations. As an example of an application, the device was used to carry out a polymerase chain reaction in which a non detectable concentration of a DNA segment was sufficiently amplified so as to enable separation and detection by electrophoresis.
Modeling, Simulation and Testing of Non-Linear Resonance Behavior in MEMS Torsional Mirrors With Mechanical-Electrostatic Coupling
Authors: Rensing Noa M. , Dodson Stuart , Adams George G. , Zavracky Paul M. , McClelland Robert W. , Lemoncelli Anthony 
Published: December 2021

Abstract
In order to obtain high angular displacement, MEMS micromirrors can be driven at resonance. This paper presents experimental and modeling results on the displacement as a function of drive amplitude for standard nickel and nanocrystalline nickel springs in two geometries. Although the resonance frequency of the torsional MEMS oscillators is adequately predicted by a linear mechanical model of the system, prediction of the angular motion at the design displacements requires attention to non-linear effects. Thus a model is proposed which incorporates non-linear effects due to the displacement of the mirror-spring system from its equilibrium position.
Silicon Microrelays With Optimized Electrostatic Actuator
Authors: Schimkat Joachim 
Published: December 2021

Abstract
The design of the electrostatic moving wedge actuator for silicon microrelays was improved towards higher contact force and lower driving voltage. Additional degrees of freedom were included in the design, providing capabilities for tuning the switching characteristics according to the contact material requirements. The relationship of the new geometric parameters and the switching characteristics was determined by simulation. Optimized silicon microrelays exhibit contact forces up to 0.9 mN at nominal voltages of 12 V or 24 V. Further outstanding qualities are the high shock resistance and the nearly neglectable driving power. The commercial application of silicon microrelays will focus on small current applications.
The Fabrication of Micro Mold Inserts Using Thick Film Resist Approach
Authors: Yu Huinan , Ganser Dale , Gehoski Kathleen A. , Mancini David , Rhine David , Smekal Thomas , Grodzinski Piotr 
Published: December 2021

Abstract
This paper reports the use of dry film resists and two spunon thick film photoresist (AZ9260 and SU8) as template in the fabrication of micro mold inserts for disposable plastic microfluidic devices.
Development of Planar Microfluidic Systems Using Conventional and Low Temperature Assembling Schemes for Components
Authors: Okulan Nihat , Bhansali Shekhar , Han Arum , Dharmatilleke Saman , Choi Jin-Woo , Patel Manoj , Oh Kwang W. , Henderson H. Thurman , Ahn Chong H. 
Published: December 2021

Abstract
This center is currently working on the development of a remotely accessible generic microfluidic system (“lab on a chip”) for biological and biochemical analysis, based on electrochemical detection techniques. Modular microfluidic components, including micro reservoirs, microvalves, micropumps, filterless magnetic particle separators, biosensors and flowsensors, were fabricated and tested, and integrated on a system motherboard. Other air-to-liquid measurand concentrators and integrated sieve/filters are being explored in related efforts. The fabrication of these microfluidic components and the utilization of wax for low temperature assembly and even bonding is discussed.
Investigation of Micro-Scale Materials Behavior With MEMS
Authors: Haque M. A. , Saif M. T. A. 
Published: December 2021

Abstract
This study presents a methodology for uniaxial tension testing of both micron and sub-micron scale specimens using MEMS devices. The methodology allows free standing, single or multi-layered specimens to be fabricated separately from the MEMS device. The MEMS device is a comb drive actuator which can be calibrated for force measurement. Materials behavior can be observed in-situ in analytical chambers such as SEM and TEM and under different environmental conditions. The methodology is demonstrated with the testing of a free standing polymer and an Aluminum specimen with thickness 1.3 microns and 110 nanometers respectively. Significant deviation in materials behavior is observed between bulk and micro-scale.
Characteristics of 12 μm Thick Polysilicon for an Optically-Sensed Accelerometer
Authors: Chen Y. H. , Kudrle T. D. , Tien N. C. 
Published: December 2021

Abstract
A low-stress thick polysilicon surface micromachining process has been successfully developed. An accelerometer composed of a 12μm thick polysilicon layer and an integrated photo diode on the substrate was fabricated and tested demonstrating the functionality of the process. The polysilicon film has an estimated stress of 0.6 MPa (tensile). This new technology combines some of the advantages of high-aspect-ratio bulk-micromachining such as large capacitance and high out-of-plane stiffness, with the proven advantages typically found for surface micromachining such as the formation of multi-level elements.
In this paper, we first present the optimized process flow, which provides the low-stress thick polysilicon film. Then, the important characteristics of thick polysilicon films such as internal stress, stress gradient and surface roughness are discussed. Testing of the integrated photodiode was performed. Finally, the initial testing results for the accelerometer are presented to demonstrate the success of this newly developed technology.
Design, Analysis, Fabrication, and Testing of a MEMS Flow Sensor
Authors: Barnes Terrence G. , Truong Thieu Q. , Lu Xiaoqing , McGruer Nicol E. , Adams George G. 
Published: December 2021

Abstract
A new type of MEMS flow sensor has been designed, analyzed, fabricated, and tested. This sensor consists of a surface micromachined switch with a complex cantilever shape. A portion of the sensor is bent at a right angle to the substrate and to the flow direction. The fluid flow produces a pressure on the sensor; sufficient pressure causes the switch to close at the designed flow rate. These flow sensors have been developed for a large multi-university project for the design and construction of a biomimetic underwater lobster robot to be used to search for and destroy mines. However, we envision a variety of other uses for these flow sensors, including biomedical applications such as blood flow measurement.
The fabrication process is based on the Northeastern University Metal Micromachining (NUMEM) technology [1]. The NUMEM process has been used to fabricate various surface micromachined metallic structures such as microrelays, microinterferometers, micromirrors, and microaccelerometers.
The analysis of these devices consists of using incompressible fluid mechanics to determine the pressure acting on the sensor and beam theory to model the resulting deflection of the switch. The first set of flow sensors was designed to close at flow velocities of 0.5, 1.0, 3.4, and 5.4 m/s. The area of the paddle, which lies in the flow, is varied in order to obtain sensors that close at different flow rates. The results of testing agree well with the analytical predictions. Although these flow sensors are unidirectional, an array of four sensors at each point can be used to determine the flow velocity and direction.
Characterization of Shear Stress Field Induced by Obliquely Impinging Airjets
Authors: Biegelsen David K. , Panides Elias , Swartz Lars E. , Jackson Warren B. , Berlin Andrew A. 
Published: December 2021

Abstract
Air jets obliquely incident on the surface of an object can produce sizable, localized, tangential forces. A MEMS-like system with tilted jets oriented in the four cardinal directions has been fabricated using extensions to printed circuit board technology. In this paper the fluid dynamic characteristics of the jets are reported. Jets approximately 1 mm in diameter are driven by pressure drops of ∼0.5 kPa. The shear stresses produced on an opposing wall (simulating a levitated object) are mapped both physically and in computational simulation. The shear stress distributions and the variations with pressure drop, channel height, jet diameter and jet tilt angle are reported.
Development of a Latching Valve for Micro-Chem-Lab™
Authors: Wong C. Channy , Adkins Douglas R. , Manginell Ronald P. , Frye-Mason Gregory C. , Hesketh Peter J. , Stanczyk Thomas 
Published: December 2021

Abstract
An integrated microsystem to detect traces of chemical agents (μChemLab™) is being developed at Sandia for counter-terrorism and nonproliferation applications. This microsystem has two modes of operation: liquid and gas phase detection. For the gas phase detection, we are integrating these critical components: a preconcentrator for sample collection, a gas chromatographic (GC) separator, a chemically selective flexural plate wave (FPW) array mass detector, and a latching valve onto a single chip. By fabricating these components onto a single integrated system (μChemLab™ on a chip), the advantages of reduced dead volume, lower power consumption, and smaller physical size can be realized. In this paper, the development of a latching valve will be presented.
The key design parameters for this latching valve are: a volumetric flow rate of 1 mL/min, a maximum hold-off pressure of 40 kPa (6 psi), a relatively low power, and a fast response time. These requirements have led to the design of a magnetically actuated latching relay diaphragm valve. Magnetic actuation is chosen because it can achieve sufficient force to effectively seal against back pressure and its power consumption is relatively low. The actuation time is rapid, and valve can latch in either an open or closed state. A corrugated parylene membrane is used to separate the working fluid from internal components of the valve. Corrugations in the parylene ensure that the diaphragm presents minimum resistance to the actuator for a relativley large deflection.
Two different designs and their performance of the magnetic actuation have been evaluated. The first uses a linear magnetic drive mechanism, and the second uses a relay mechanism. Preliminary results of the valve performance indicates that the required driving voltage is about 10 volts, the measured flow rate is about 50 mL/min, and it can hold off pressure of about 5 psi (34 kPa). Latest modifications of the design show excellent performance improvements.
High Fidelity and Compact Models of Synthetic Jets and Their Application in Aerodynamics and Microelectronics
Authors: Przekwas Andrzej J. , Chen Zhijian , Turowski Marek 
Published: December 2021

Abstract
Computational simulation of coupled unsteady fluid mechanics and electromechanical actuation of a single synthetic jet can be performed with available CFD tools. Modeling of flow physics of large arrays of synthetic jets is computationally very challenging. This paper presents two complementary computational technologies: a high-fidelity physical model of a single jet, and a reduced (compact) model of the jet for modeling large array of synthetic jets. The high-fidelity model first has been validated against experimental data and then used to calibrate the compact model.
The paper presents computational evaluation of accuracy and range of applicability of compact models and demonstrates them on multi-dimensional simulations of aerodynamic flow control and on electronics cooling applications.
An Actively Controlled Micromixer
Authors: Volpert Marion , Meinhart Carl D. , Mezic Igor , Dahleh Mohammed 
Published: December 2021

Abstract
An active mixing strategy has been developed to enhance mixing of two fluids through a microchannel. Mixing is enhanced when the flow through the main channel of the mixer is perturbed by three sets of secondary flow channels. Numerical solutions of the flow through the mixer are calculated by simulating the full Navier-Stokes equation, the Stokes equation, and a simple analytical model based upon the superposition of elementary velocity profiles. The analytical model agrees qualitatively with Navier-Stokes and Stokes solutions for Reynolds numbers, Re = 5. A mixing coefficient is developed to quantitatively evaluate mixing efficiency for various flow configurations. The results indicate enhanced mixing for two possible flow configurations.
Dielectrophoretic Manipulation of Particles for Use in Microfluidic Devices
Authors: Miles Robin , Belgrader Phil , Bettencourt Kerry , Hamilton Julie , Nasarabadi Shanavaz 
Published: December 2021

Abstract
Amplification and hybridization of DNA are commonly used techniques to verify the presence of a specific DNA sequence in a test sample. Automatic sample handling to concentrate and purify a sample prior to amplification is desirable to increase the sensitivity of the test, to reduce the possibility of sample contamination such as inhibitors and to reduce reagent use. This paper explores the use of the dielectrophoretic force to manipulate DNA, Bacillus globigii spores and Erwinia herbicola bacteria to provide both concentration and purification as part of the sample handling functions in biological assay equipment. It was found that typical microfabricated structures with electrode gaps of 30μm operating at 5V could achieve very effective concentration of these particles.
Near-Field Electromagnetic Shielding Effect of On-Chip Electroplated Copper Layers
Authors: Kang Tae Goo , Cho Young-Ho 
Published: December 2021

Abstract
An experimental investigation on the near field electromagnetic loss of thin copper layers has been presented for applications to multi-chip microsystems with on-chip electromagnetic protection. Copper layers in the thickness range of 0.2 μm∼200μm have been electroplated on the silicon substrates. A pair of microwave transceivers has been fabricated using the 3.5mm × 3.5mm nickel microloop antennas, electroformed on the silicon substrates. Electromagnetic radiation loss has been measured for the copper layers placed between the microloop transceivers, resulting in the electromagnetic shield effectiveness of 10dB∼40dB for the wave frequency range of 100MHz ∼ 1GHz. The 0.2μm-thick copper layer provides a shield loss of 20dB at the frequencies higher than 300MHz, whereas showing a predominant decrease of shield loss to 10dB level at lower frequencies. No substantial increase of the shield effectiveness has been found for the copper shield layers thicker than 2μm.
The Electro-Thermally Driven Micro Membrane Actuators With Two-Way Deflection
Authors: Hsu Chen Peng , Hsu Wensyang 
Published: December 2021

Abstract
This paper presents design, simulation, fabrication, and testing of two types of two-way micro membrane actuators able to deflect in both upward and downward directions with continuous deflections. Both actuators are electro-thermally driven, comprising of aluminum and silicon dioxide served as the main materials of top and bottom layer. In testing, the driving voltage is less than 4 volts and the power consumption is less than 400 mW. The upward deflections of the membrane actuators for the first design and the second design are 50 μm and 40 μm respectively, and both designs can achieve downward deflections of 15 μm. However, the characteristic of operation for each design is different.
Thermal Conductivity of Porous Silicon Layers for MEMS
Authors: Srinivasan Uma , Breh Peter , Asheghi Mehdi , Touzelbaev Maxat , Goodson Kenneth E. 
Published: December 2021

Abstract
Porous silicon is a promising material for MEMS because of its unique electrical, thermal, optical, and absorptive properties. This work measures the thermal conductivity of a silicon layer with 40 percent porosity at temperatures between 20 and 300 K using Joule heating and electrical-resistance thermometry. The room-temperature thermal conductivity is 0.43 Wm−1K−1, which is almost three orders of magnitude less than the value for single-crystal silicon. The data are interpreted using a new model based on electron microscopy, which shows a sponge-like morphology with embedded crystalline regions. The model separately treats the contributions of the sponge-like material, in which the solid regions are assumed to be amorphous silicon, and the larger crystallites, in which the conductivity is reduced by boundary scattering. The present work is particularly useful for MEMS based on silicon with porosity below 50 percent, for which no thermal conductivity data were previously available.
Biological Force Measurements Using Micromachined Cantilevers
Authors: Liang Y. , Welch J. N. , Rudnitsky R. G. , Kenny T. W. 
Published: December 2021

Abstract
There are many interesting biological systems that utilize small mechanical forces to achieve functionality. Protein folding, ligand-receptor binding, cellular adhesion, and others all rely on picoNewton sized mechanical forces. In many of these examples, the fundamental character of the interaction remains controversial. In this paper, we describe work in progress to develop micromechanical force-measuring instruments suitable for measurements of these small biologically derived forces.
A Simple Silicon Based Nitric Oxide Sensor
Authors: Bariatto Marcelo , Furlan Rogerio , Arakai Koiti , Santiago-Aviles Jorge J. 
Published: December 2021

Abstract
Nitric oxide (NO) is known to mediate many beneficial physiology processes, motivating its detection in vivo as well as in vitro. Electrochemical detection provides the required cellular level determination of NO among several other techniques.
In this work, electrochemical micro-sensors for both types of detection, in vivo and in vitro, were developed, exploring the silicon planar technology, which presents high yield and reliability and also permits batch fabrication.
The developed in vitro sensor features eight detection sites (10 μm × 10 μm microelectrodes), for determination of nitric oxide spatial distribution or multi-species analysis. Different electrochemical methods were applied to provide sensor calibration and chemical reproducibility.
For in vivo analysis, the designed structures have a needle shape (40 μm thick) and they were silicon micro-machined by using plasma etching or etch stop techniques. Different configurations were designed and implemented, containing a number of detection microelectrodes that vary from 2 to 10.
The amperometric detection of both nitric oxide and nitride (NO2−) — a molecule that causes an interference — were investigated by using the in vitro micro-sensor configuration. The need of a cationic exchanger (Nafion) was demonstrated in order to provide selectivity to NO for low concentrations. Also, the developed sensor has a sensitivity of 500 A/M.cm2 and a detection limit of 10 μM.
Adapting an Articulated Vehicle to the Drivers
Authors: Yang Xiaobo , Rakheja Subhash , Stiharu Ion 
Published: December 2021

Abstract
A yaw plane model with limited roll DOF of a five-axle tractor semitrailer is developed to study the open-loop directional dynamics of the vehicle. A comprehensive driver model incorporating path preview, low and high frequency compensatory gains and time delays, and prediction of tractor lateral acceleration, articulation rate of the combination and the trailer sprung mass roll angle is developed and integrated with the vehicle model. The coupled driver-vehicle model is analyzed to explore the performance potentials of the vehicle design adapted for control limits of the driver. The data reported in the published studies are reviewed to identify range of control limits of the drivers in terms of preview distance, reaction time and compensatory gain. A comprehensive performance index including the path tracking, vehicle dynamic response characteristics and the driver’s steering effort is formulated and minimized using Gauss-Newton method to derive the desirable ranges of the vehicle parameters, including geometric, inertial, suspension, tire and the fifth wheel. The results of the study revealed that a driver with higher skill can easily adapt the vehicle with large size, soft suspension and relative over-steer nature. The adaptability of the vehicle is further examined for different drivers with varying skills. It is concluded that the adaptability and thus the directional performance of the vehicle can be enhanced through variations in the weights and dimensions, and suspension, tire and the fifth wheel properties. The results further show that the driver-adapted vehicle yields up to 33% reduction in the steering effort demand posed on the driver, while the roll angle and yaw rate response decrease by up to 40%.