bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gas Transport by Thermal Transpiration in Micro-Channels: A Numerical Study
Authors: Wong C. Channy , Hudson Mary L. , Potter Donald L. , Bartel Tim J. 
Published: February 2022

Abstract
A reliable micro gas pump is an essential element to the development of many micro-systems for chemical gas analyses. At Sandia, we are exploring a different pumping mechanism, gas transport by thermal transpiration. Thermal transpiration refers to the rarefied gas dynamics developed in a micro-channel with a longitudinal temperature gradient. To investigate the potential of thermal transpiration for gas pumping in micro-systems, we have performed simulations and model analysis to design micro-devices and to assess their design performance before the fabrication process. Our effort is to apply ICARUS (a Direct Simulation Monte Carlo code developed at Sandia) to characterize the fluid transport and evaluate the design performance. The design being considered has two plenums at different temperatures (hot and cold) separated by a micro-channel of 0.1 micron wide and 1 micron long. The temperature difference between the two plenums is 30 Kelvin. ICARUS results, a quasi-steady analysis, predicts a net flow through the micro-channel with a velocity magnitude of about 0.4 m/s due to temperature gradient at the wall (thermal creep flow) at the early time. Later as the pressure builds up in the hot plenum, flow is reversed. Eventually when the system reaches steady state equilibrium, the net flow becomes zero. The thermal creep effect is compensated by the thermo-molecular pressure effect. This result demonstrates that it is important to include the thermo-molecular pressure effect when designing a pumping mechanism based on thermal transpiration. The DSMC technique can model this complex thermal transpiration problem.
Thin Film Microresonator for Vacuum Sensing
Authors: Yuan F. , Tom C. L. , Mastrangelo C. H. , Martin J. , Pfenninger R. 
Published: February 2022

Abstract
This paper reports the fabrication and testing of a silicon micromachined resonator suitable for vacuum sensing applications. The device consist of a circular bossed 1 mm-diameter, 5 μm-thick p++ silicon plate anodically bonded to a 7740 Pyrex glass wafer. The device is fabricated with 4 lithographic steps using the dissolved silicon wafer process. Both the resonator natural frequency and its quality factor are functions of gas pressure in the 101 – 10−4 Torr range.
Design of Resonant Beam Transducers: An Axial Force Probe for Atomic Force Microscopy
Authors: Harley Jonah A. , Chow Eugene M. , Kenny Thomas W. 
Published: February 2022

Abstract
Guidelines for the mechanical design of resonant beam force transducers are developed. By considering the effects of beam dimensions on the force sensitivity, it is shown that thin, narrow beams are optimal for resonant sensing. Sensitivity is also shown to be inversely dependent on the amplitude of oscillation, and linear with the resonance quality (Q) of the oscillator. Based on this analysis, an axial resonant force detector was developed for use in atomic force microscopy. Initial measured results in air with a Q of 15 and 60nm oscillations give 33nN force resolution in a 1 kHz bandwidth. The Q improves to 1200 in moderate vacuum, yielding an expected force resolution of 10pN in a 1 kHz bandwidth. Due to its high axial spring constant (∼200N/m) and vertical orientation, this force probe has the added benefit for surface force measurements that it is not susceptible to snap-down or other force instability.
A Micro-Actuator for a Hard-Disk Drive Fine Tracking Servo
Authors: Hirano Toshiki , Fan Long-Sheng , Lee Wen Y. , Hong John , Semba Tetsuo , Imaino Wayne , Pattanaik Surya , Chan Susanna , Webb Patrick 
Published: February 2022

Abstract
This paper reports on the design, fabrication and testing of an electrostatic micro-actuator for a magnetic Hard-Disk Drive (HDD) tracking servo. First, the design requirements for a micro-actuator in this application were investigated. These include high Z-directional stiffness, low in-plane stiffness, high structural aspect ratio, large output force, high area-efficiency, low cost, and mass-production by a batch process. A novel area-efficient rotary micro-actuator design was devised, and micro-actuators were successfully fabricated using innovative processing technologies such as high-aspect ratio polymer etching and thick metal electro-deposition. The fabricated micro-actuator has a structural thickness of 40 μm with a minimum gap/structure width of approximately 2 μm (aspect ratio of 20:1). The micro-actuator’s frequency response was measured and it was confirmed that the micro-actuator has extremely clean response up to very high frequency region, and this fact enables the design of a servo system that exceeds a 5 kHz servo bandwidth, which is adequate to achieve a track density of more than 25 kilo-track-per-inch (kTPI).
The micro-actuator/slider assembly was also tested on a spinning disk, with its position controlled by a PID controller using the magnetic position error signal (PES) written on the disk. A position accuracy of about 0.05 μm was observed when the servo controller was turned on. This result confirms that this micro-actuator can be used in a servo system which is capable of more than 25 kTPI.
Parametric Resonance in a Microelectromechanical Torsional Oscillator
Authors: Turner Kimberly L. , Hartwell Peter G. , Bertsch Fred M. , MacDonald Noel C. 
Published: February 2022

Abstract
In various MEMS devices, it has been observed that mechanical instabilities can occur with driving frequencies other than resonance[1]. One such device is the torsional scanning probe z-actuator with an integrated tip. Previously reported work identified five Matheiu instability frequencies, and an experimental map of the first two instability region[1]. In this paper, we extend that work to show the effects of damping on the instabilities. The motion of this system is described by Mathieu-type equations, which has been extensively studied theoretically, but damping of the system has prohibited most experiments from displaying the wide range of instabilities predicted by theory [2]. In our experiment, a laser vibrometer is mounted on an optical microscope to precisely measure device motion. We show that the boundary between stable and unstable solutions is extremely sharp. Behavior of the device near the instability boundaries can be applied to improvements filter technology and small force sensing.
Design and Strength Evaluation of an Anodically Bonded Pressurized Cavity Array for Wafer-Level MEMS Packaging
Authors: Go Jeung Sang , Cho Young-Ho 
Published: February 2022

Abstract
We present the design and strength evaluation of an anodically bonded pressurized cavity array, based on the energy release rate measured from the anodically bonded plates of two dissimilar materials. From a theoretical analysis, a simple fracture mechanics model of the pressurized cavity array has been developed. The energy release rate (ERR) of the bonded cavity with an infinite bonding length has been derived in terms of cavity pressure, cavity size, bonding length, plate size and material properties. The ERR with a finite bonding length has been evaluated from the finite element analysis performed for varying cavity and plate sizes. It is found that, for an inter-cavity bonding length greater than the half of the cavity length, the bonding strength of cavity array approaches to that of the infinite plate. For a shorter bonding length, however, the bonding strength of the cavity array is monotonically decreased with the ratio of the bonding length to the cavity length. The critical ERR of 6.21J/m2 has been measured from anodically bonded silicon-glass plates. A set of critical pressure curves has been generated for varying cavity array sizes, and a design method of the pressurized cavity array has been developed for the failure-free wafer-level packaging of MEMS devices.
Analysis on Multi-Layered, Corrugated Diaphragm With Residual Stress
Authors: Yan Hai , Lou Kuok Chun , Lee Byungchai , Kim Eun Sok 
Published: February 2022

Abstract
This paper describes the use of Finite Difference Method (FDM) to analyze a multiple-layered, corrugated rectangular diaphragm subject to residual stress for MEMS applications. The corrugated part of the diaphragm is treated as a flat plate with anisotropic mechanical properties. The multiple-layered structure is treated as a single-layered plate with an effective Young’s modulus. The effect of the residual stresses in the diaphragm layers is simulated with in-plane normal forces in the neutral plane at the four boundary edges of the diaphragm. This way, the complicated analysis on a corrugated, multiple-layered diaphragm with various residual stresses in the layers is greatly simplified, and can be done by FDM without sacrificing accuracy much. Both deflection and stress distribution of the diaphragm under a uniformly applied pressure have been analyzed, although the technique is also applicable for a non-uniform pressure. And we discuss the effects of corrugation depth, period and width on the deflection and stress distribution of the diaphragm. Finally, we describe an example of using this method to design a micromachined, corrugated-diaphragm, piezoelectric microphone in which the residual stress plays a critical role in limiting the performance.
Fracture and Sub-Critical Crack Growth Behavior of Micromachined Single Crystal Silicon Structures
Authors: Fitzgerald Alissa M. , Iyer R. Suryanarayanan , Dauskardt Reinhold H. , Kenny Thomas W. 
Published: February 2022

Abstract
Currently little data exists on the fracture and subcritical crack growth behavior of single crystal silicon, a common material for micromachined devices. In order to obtain stable crack growth in silicon, we utilize a decreasing stress intensity specimen geometry (Gonzales and Pantano, 1990). We present new data on crack growth rates in silicon as a function of applied stress intensity (K). We made direct measurements of these values via optical and electrical resistance techniques under monotonic loading conditions. We also present new data on the critical stress intensity (KIc) of silicon for a sample of micromachined proportions.
Thermal Flow Sensor for Liquids and Gases
Authors: Ashauer M. , Glosch H. , Hedrich F. , Hey N. , Sandmaier H. , Lang W. 
Published: February 2022

Abstract
A new type of a flow sensor is presented which is based on a thermal principle. The combination of two detecting methods results both in a considerable increase in measuring range (0.1 to 150 mm/s) and in a shorter reaction time of less than 2 ms. Furthermore, the sensor is relatively insensitive to pollution. Devices were manufactured and successfully tested for liquids and gases.
Suspended Moving Channels and Channel Actuators for Microfluidic Applications
Authors: Chong John M. , MacDonald Noel C. 
Published: February 2022

Abstract
A novel process for fabricating suspended moving channels has been developed. With this process we are able to produce microfluidic channels above the substrate as well as channels embedded just below the surface. By design, the process allows the core of single crystal silicon (SCS) beams to be removed leaving a hollow interior that can carry fluids. Thus, portions of actuators or entire actuators can contain and carry fluids. The result is total integration of channels with actuators and other high aspect ratio structures.
The nature of the process makes integration of these suspended channels with actuators extremely simple. Only two masks are required: one to define the actuators and another to define the channels. A third mask can be used to pattern the metal allowing for opaque and transparent channels. Suspending channels above the substrate opens a wide range of new possibilities: greater thermal isolation between channels; a method for mixing fluids; a means for pumping fluids; and a means for sensing density by monitoring resonance changes. In addition, the channels are accessible for both optical monitoring and optical excitation of chemical reactions.
Velocimetry for MEMS Applications
Authors: Wereley Steven T. , Meinhart Carl D. , Santiago Juan G. , Adrian Ron J. 
Published: February 2022

Abstract
Particle image velocimetry (PIV), a technique commonly used at macroscopic length scales to measure velocity fields of particle-seeded flows, is adapted to measure velocity fields in microfluidic MEMS devices, where micron-scale spatial resolution is critical. Adapting PIV to the microscopic level presents a number of challenges, including visualizing tracer particles that are smaller than the wavelength of light and minimizing errors due to the Brownian motion of the tracer particles. High numerical aperture video microscopy is used to record the faint signals from fluorescent 300 nm particles. Innovative ensemble averaging and adaptive spatial shifting algorithms are used to extract maximal information from the recorded images. The PIV technique is used to measure a low Reynolds number Hele-Shaw flow around an 8 μm human red blood cell. The velocity vector field presented has a maximal spatial resolution of 3.2 × 3.2 × 1.5 μm.
Microactuation by Continuous Electrowetting Phenomenon and Silicon Deep RIE Process
Authors: Lee Junghoon , Kim Chang-Jin “CJ” 
Published: February 2022

Abstract
This paper reports a new, deep reactive-ion-etching (DRIE) based microfabrication method to realize continuous electrowetting (CEW) for MEMS. CEW is a surface-tension driven actuation mechanism that drives a liquid-metal droplet along an electrolyte-filled microchannel by controlling the surface tension of the liquid metal with electric potential. DRIE process enables us to use silicon dioxide microchannel instead of the previously reported polymer which raised the question of long-term material compatibility between the electrolyte and channel material. The paper also discusses the design issues and scaling law to use CEW for microscale devices, revealing many advantages and justifying the CEW as a powerful microactuation principle for MEMS application. Experiment proved the effectiveness by demonstrating a low-voltage, low-power consumption, and high-speed operation in microscale. We obtained the speed of ∼10 cm/s for a mercury slug at an operating voltage less than 3 V and average current around 10 μA. A liquid micromotor with loop diameter of 2 mm demonstrates reliable operation (i.e., circling of the slug along the loop) at 420 rpm. Some of the possible applications include memory device, optical switch, microgyroscope, and angular inertial actuation device.
Anisotropic Crystalline Etching Simulation Using a Continuous Cellular Automata Algorithm
Authors: Zhu Zhenjun , Liu Chang 
Published: February 2022

Abstract
We present results on the development of an anisotropic crystalline etching simulation (ACES) program based on a new continuous Cellular Automata (CA) model. The program provides accurate modeling of etching process with high spatial resolution. Implementation of a dynamic CA technique has resulted in increased simulation speed and reduced memory requirements. A first ACES software based on PC platforms has been realized.
MEMS Codesign: First Full-System Inertial Microsensor Design Tool
Authors: Pottenger Michael D. , Kaiser William J. 
Published: February 2022

Abstract
We present the first inertial microsensor stand-alone simulation tool capable of modeling an entire sensor system, based on discrete-time methods and implemented in SPICE. Included are all electrical and thermomechanical noise sources, proof mass dynamics, differential capacitive transducer bridge, interface circuit, and feedback control. Complete microsensor system performance can be simulated in the time domain, incorporating flicker noise models based on measured data from a commercial CMOS process. Sensor design methodology, modeling and simulation concerns are addressed. Results appear in a companion paper also published in this volume.
ASME OM ISTB Code Vibration Changes: Vibration Calibration Frequency Response Range and Wording Changes
Authors: Hudson Edward , Anderson David , Camilli Nick 
Published: February 2022

Abstract
In July of year 2020, The Electric Power Research Institute (EPRI) Condition Based Maintenance User Group (CBMUG) held an annual meeting. During the proceedings, the group requested that an effort be made to pursue changes to ASME OM ISTB. Two changes were requested:
1. Changes to ISTB-3510 concerning calibration of vibration instruments at low frequencies.
2. Changes to various locations wording concerning the use of the term “broadband (unfiltered)” vibration data.
In July of 2020, EPRI submitted proposed changes to the ASME ISTB Code Committee and presented the requests during a virtual meeting.
Change 1: Operating Nuclear Plants are required by NUREG-1482 to follow ASME OM ISTB-3510(e) calibration requirements for vibration instruments used for in-service testing. Instruments accuracy must be ± 5% from 1/3 running speed to at least 1000 Hz. The industry has historically experienced difficulty in meeting this requirement on slow speed pumps resulting in proliferation of relief requests in the late 1980’s and early 1990’s. Revision of NUREG-1482 in 2013 caused concerns among users in relation to the validity of the existing reliefs.
Change 2: The term “Broadband Unfiltered” is used in various locations in the OM code to describe vibration data. This terminology was common in an earlier era of analog vibration data collection equipment but is confusing to a new generation of vibration analysts accustomed to using modern digital vibration instruments.
Boron proxies record paleosalinity variation in the North American Midcontinent Sea in response to Carboniferous glacio-eustasy
Authors: Wei Wei , Yu Wenchao , Algeo Thomas J. , Herrmann Achim D. , Zhou Lian , Liu Jinhua , Wang Qian , Du Yuansheng 
Published: February 2022

Abstract
Salinity variation in ancient epicontinental seas has long been challenging to reconstruct. We determined salinity variation in the Late Pennsylvanian North American Midcontinent Sea based on normalized boron concentrations (B/Ga) and isotopic compositions (δ11B) of bulk shale. We analyzed the Stark Shale Member of the Missourian Stage Dennis Limestone cyclothem in the Charleston core (CC) from the Illinois Basin (eastward, more proximal) and the Iowa Riverton core (IRC) from the Midcontinent Shelf (westward, more distal). Both cores exhibited the same pattern of secular variation, with lower B/Ga and δ11B values at their base and top, recording less saline conditions during lower sea-level stands, and higher values in their middle part, recording more saline conditions at highstands—a pattern that conforms to conventional sequence stratigraphic and glacio-eustatic interpretations of Midcontinent cyclothems. At equivalent stratigraphic levels, B/Ga and δ11B values are systematically lower at CC relative to IRC, reflecting the generally lower salinity conditions of the Illinois Basin relative to the Midcontinent shelf, which is consistent with greater freshwater influence from the east due to heavy river runoff into the Appalachian foreland basin. Our findings serve to demonstrate the utility of paired B concentration and isotope data for paleosalinity analysis of deep-time shale formations.
What drives Fe depletion in calc-alkaline magma differentiation: Insights from Fe isotopes
Authors: Du De-Hong , Tang Ming , Li Weiqiang , Kay Suzanne Mahlburg , Wang Xiao-Lei 
Published: February 2022

Abstract
The continental crust is strongly depleted in iron relative to mid-oceanic ridge basalt, broadly identical to the calc-alkaline magmas, suggesting that calc-alkaline differentiation is key to continent formation. However, it remains contentious as to what drives Fe depletion during magmatic differentiation in the crust. The two competing hypotheses for calc-alkaline differentiation—magnetite versus garnet (± amphibole) fractionation—predict contrasting Fe isotopic fractionation pathways in evolved melts because magnetite preferentially depletes ferric, isotopically heavy Fe whereas garnet (± amphibole) does the opposite. We report whole-rock Fe isotope data for two suites of igneous rocks from the central Andes, which represent magmas traversing normal and thickened arc crust, respectively. The magmas traversing thickened crust show a strong Fe depletion trend and consistently high δ56Fe values (0.14‰ ± 0.02‰, 1 standard deviation [SD]), while those traversing normal crust are less depleted in Fe and show variable δ56Fe values (0.10‰ ± 0.05‰, 1SD). The two Andean suites are both isotopically heavier than Mariana arc (Pacific Ocean) magmas that differentiate along tholeiitic (Fe-enriching) paths. These results confirm that garnet (± amphibole) fractionation/retention is the primary driver of Fe depletion in calc-alkaline magmas, and highlight a role for crustal thickening in generating calc-alkaline magmas.
Voltammetric DNA Sensor Based on Redox-Active Dyes for Determining Doxorubicin
Authors: Kappo D. , Kuzin Yu. I. , Shurpik D. N. , Stoikov I. I. , Evtyugin G. A. 
Published: February 2022

Abstract
We proposed a voltammetric DNA sensor based on glassy carbon modified with carbon black, pillar[5]arene, and electropolymerized Neutral Red. To increase signal sensitivity, Methylene Blue in monomeric and polymeric forms was introduced into the surface layer of the DNA sensor as a specific DNA intercalator and electron transfer mediator. The electrochemical characteristics of the coating are determined, depending on the composition and the preparation method; a consistent change in the peak currents of dyes is observed during the incubation of a DNA sensor in a solution of doxorubicin as a model anticancer drug. Under optimal conditions, the DNA sensor enables the determination of 10 nM to 0.1 mM of doxorubicin. Doxorubicin can also be determined in synthetic blood plasma.