Investigation of the Deposition and Integration of Hard Coatings for Moving MEMS Applications

1999 ◽  
Vol 605 ◽  
Author(s):  
P.M. Adams ◽  
R.E. Robertson ◽  
R.C. Cole ◽  
D. Hinkley ◽  
G. Radhakrishnan
Keyword(s):  
Microelectromechanical Systems ◽  
Fundamental Problem ◽  
Three Dimensional ◽  
Hard Coatings ◽  
Three Dimensions ◽  
Small Scale ◽  
Mems Devices ◽  
Wear Resistant ◽  
Integrated Electronics ◽  
Poly Silicon

AbstractMicroelectromechanical systems (MEMS) have been identified as a key technology for small-scale satellites, integrated sensors, and intelligent control systems. Using methods developed for highly integrated electronics, mechanical components are co-fabricated on planar wafers and subsequently etched free for mechanical movements in three dimensions. A major design limitation for these systems is their inability to withstand prolonged sliding surface contact. The fundamental problem is that the surface properties of silicon and poly-silicon, two of the most widely used materials for MEMS, are highly unsuitable for moving MEMS devices, resulting in high wear during operation. This work explores the feasibility and benefits of depositing thin, wear-resistant, low-friction coatings on silicon or poly-silicon. To achieve this goal, three-dimensional test silicon microstructures have been fabricated. Wear-resistant titanium carbide (TiC) coatings are deposited on these test structures using a novel non-line-of-sight pulsed laser deposition (PLD) process. In parallel, this paper addresses the integration of the TiC coating directly into the MEMS fabrication processes and its compatibility with standard silicon processing.

A Review on Laser Processing in Electronic and MEMS Packaging

2017 ◽  
Vol 139 (3) ◽  
Author(s):  
Kaysar Rahim ◽  
Ahsan Mian
Keyword(s):  
Laser Processing ◽  
Microelectromechanical Systems ◽  
Mechanical Effect ◽  
Future Trend ◽  
Small Scale ◽  
Attractive Alternative ◽  
Mems Devices ◽  
Processing Technologies ◽  
Mems Packaging ◽  
Heating And Cooling

The packaging of electronic and microelectromechanical systems (MEMS) devices is an important part of the overall manufacturing process as it ensures mechanical robustness as well as required electrical/electromechanical functionalities. The packaging integration process involves the selection of packaging materials and technology, process design, fabrication, and testing. As the demand of functionalities of an electronic or MEMS device is increasing every passing year, chip size is getting larger and is occupying the majority of space within a package. This requires innovative packaging technologies so that integration can be done with less thermal/mechanical effect on the nearby components. Laser processing technologies for electronic and MEMS packaging have potential to obviate some of the difficulties associated with traditional packaging technologies and can become an attractive alternative for small-scale integration of components. As laser processing involves very fast localized and heating and cooling, the laser can be focused at micrometer scale to perform various packaging processes such as dicing, joining, and patterning at the microscale with minimal or no thermal effect on surrounding material or structure. As such, various laser processing technologies are currently being explored by researchers and also being utilized by electronic and MEMS packaging industries. This paper reviews the current and future trend of electronic and MEMS packaging and their manufacturing processes. Emphasis is given to the laser processing techniques that have the potential to revolutionize the future manufacturing of electronic and MEMS packages.

scholarly journals Walkabout in Another World

2000 ◽  
Vol 122 (11) ◽  
pp. 98-101 ◽  
Author(s):  
Jean Thilmany
Keyword(s):  
Virtual Reality ◽  
Product Design ◽  
Motion Tracking ◽  
New Technology ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Mems Devices ◽  
The Road ◽  
Naked Eye ◽  
Hands On

This article discusses that virtual reality can be expected to be the next big thing in product design and prototype, especially for products too small to be seen with the naked eye. Virtual reality will be new technology for engineering, according to many companies. Virtual reality applications could become commonplace as soon as five years down the road. By using virtual reality systems, designers touch a stylus or pen to manipulate a three-dimensional image. They get their hands on tiny sensing devices, the way you would tinker under the hood of a car. They can still determine, through the system’s visualization and animation capabilities, how the MEMS devices will function in their tiny world. Intersense of Burlington, MA, provides the motion-tracking sensors that literally track a user’s eyes and hand motions, to ensure the object they feel and manipulate in three dimensions matches the movements of their hands and eyes. It is this key piece of technology that allows users to interact in a three-dimensional environment the same way they move in their real environments.

On the Micromechanical Characterization of Metallic MEMS by a Hybrid Microtester

2015 ◽  
Author(s):  
Jennifer Wardlow ◽  
Seyed Allameh
Keyword(s):  
Mechanical Properties ◽  
Microelectromechanical Systems ◽  
Local Deformation ◽  
Small Scale ◽  
Large Displacements ◽  
Mems Devices ◽  
Surface Flaws ◽  
Micromechanical Characterization ◽  
Position Monitoring

Mechanical testing of microelectromechanical systems (MEMS) components helps investigate the reliability of MEMS devices used especially in vital applications such as life-supporting, medical, aerospace or automotive technologies. This paper discusses the development and use of a hybrid micromechanical system that combines the advantages of a macroscale slow-action screw-driven stage producing large displacements with a small-scale fast-action piezo-driven actuator. The main advantage is to study mechanical properties of small structures such as thick and thin films developing cracks that travel on millimeter scale during fatigue. The combination of piezo position monitoring with image-recognition-based local deformation determination allows specification of the beginning of phenomena such as micro-void-induced softening with relative accuracy. Such studies are most useful for investigation of the onset of nucleation of microcracks from fatigue-induced surface flaws. The significance of finding the onset of crack propagation lies in the fact that crack initiation constitutes the major portion of fatigue life for small structures (occasionally up to 99.3%).

Fine-Scale Simulation of Sandstone Acidizing

2005 ◽  
Vol 127 (3) ◽  
pp. 225-232 ◽  
Author(s):  
Chunlou Li ◽  
Tao Xie ◽  
Maysam Pournik ◽  
Ding Zhu ◽  
A. D. Hill
Keyword(s):  
Flow Field ◽  
Three Dimensional ◽  
Axial Direction ◽  
Three Dimensions ◽  
Scale Model ◽  
Small Scale ◽  
Fine Scale ◽  
Homogeneous Case ◽  
The Matrix ◽  
Highly Correlated

We have developed a fine-scale model of the sandstone core acid flooding process by solving acid and mineral balance equations for a fully three-dimensional flow field that changed as acidizing proceeded. The initial porosity and mineralogy field could be generated in a correlated manner in three dimensions; thus, a laminated sandstone could be simulated. The model has been used to simulate sandstone acidizing coreflood conditions, with a 1in.diam by 2in. long core represented by 8000 grid blocks, each having different initial properties. Results from this model show that the presence of small-scale heterogeneities in a sandstone has a dramatic impact on the acidizing process. Flow field heterogeneities cause acid to penetrate much farther into the formation than would occur if the rock were homogeneous, as is assumed by standard models. When the porosity was randomly distributed (sampled from a normal distribution), the acid penetrated up to twice as fast as in the homogeneous case. When the porosity field is highly correlated in the axial direction, which represents a laminated structure, acid penetrates very rapidly into the matrix along the high-permeability streaks, reaching the end of the simulated core as much as 17 times faster than for a homogeneous case.

Self-biased Dual-phase Energy Harvesting System

2013 ◽  
Vol 1556 ◽  
Author(s):  
Yuan Zhou ◽  
Amar Bhalla ◽  
Shashank Priya
Keyword(s):  
Magnetic Field ◽  
Magnetic Energy ◽  
Synthesis Method ◽  
Three Dimensional ◽  
Deposition Process ◽  
Small Scale ◽  
Dual Phase ◽  
Mems Devices ◽  
Power Sources ◽  
Dc Magnetic Field

ABSTRACTIn this study, we report the design and fabrication of a dual-phase energy harvester which can synchronously harvest both mechanical and magnetic energy in the absence of DC magnetic field. The harvester consists of a magnetostrictive cantilever beam and a magnetostrictive/ piezoelectric (M/P) self-biased laminate composite structure. This structure allows us to utilize piezoelectric and self-biased magnetoelectric effect simultaneously. By combining these mechanisms together, a sum effect for harvesting both magnetic and vibration energy was realized under DC magnetic field free condition. The bilayer structure provides a simplified geometry that can be easily incorporated into MEMS devices. We demonstrate a hybrid synthesis method for fabrication of complex three-dimensional thin films using a cost-effective and mask-less aerosol jet deposition process. The combination of the hybrid aerosol jet process with dual phase harvester design provides the opportunity to fabricate small scale power sources required for structural health monitoring applications.

scholarly journals <i>Introduction</i>The Cluster mission

2001 ◽  
Vol 19 (10/12) ◽  
pp. 1197-1200 ◽  
Author(s):  
C. P. Escoubet ◽  
M. Fehringer ◽  
M. Goldstein
Keyword(s):  
Three Dimensional ◽  
Distribution Functions ◽  
Three Dimensions ◽  
Small Scale ◽  
Physical Parameters ◽  
Ion Distribution ◽  
Space Operations ◽  
Science Operations ◽  
Electric And Magnetic Fields ◽  
Set Up

Abstract. The Cluster mission, ESA’s first cornerstone project, together with the SOHO mission, dating back to the first proposals in 1982, was finally launched in the summer of 2000. On 16 July and 9 August, respectively, two Russian Soyuz rockets blasted off from the Russian cosmodrome in Baikonour to deliver two Cluster spacecraft, each into their proper orbit. By the end of August 2000, the four Cluster satellites had reached their final tetrahedral constellation. The commissioning of 44 instruments, both individually and as an ensemble of complementary tools, was completed five months later to ensure the optimal use of their combined observational potential. On 1 February 2001, the mission was declared operational. The main goal of the Cluster mission is to study the small-scale plasma structures in three dimensions in key plasma regions, such as the solar wind, bow shock, magnetopause, polar cusps, magnetotail and the auroral zones. With its unique capabilities of three-dimensional spatial resolution, Cluster plays a major role in the International Solar Terrestrial Program (ISTP), where Cluster and the Solar and Heliospheric Observatory (SOHO) are the European contributions. Cluster’s payload consists of state-of-the-art plasma instrumentation to measure electric and magnetic fields from the quasi-static up to high frequencies, and electron and ion distribution functions from energies of nearly 0 eV to a few MeV. The science operations are coordinated by the Joint Science Operations Centre (JSOC), at the Rutherford Appleton Laboratory (UK), and implemented by the European Space Operations Centre (ESOC), in Darmstadt, Germany. A network of eight national data centres has been set up for raw data processing, for the production of physical parameters, and their distribution to end users all over the world. The latest information on the Cluster mission can be found at http://sci.esa.int/cluster/.

convergent-beam diffraction from surfaces

1987 ◽  
Vol 45 ◽  
pp. 30-33
Author(s):  
J. A. Eades ◽  
A. E. Smith ◽  
D. F. Lynch
Keyword(s):  
Reciprocal Lattice ◽  
Three Dimensional ◽  
Grazing Incidence ◽  
Three Dimensions ◽  
Plane Figure ◽  
Transmission Electron ◽  
Convergent Beam ◽  
Beam Patterns ◽  
Beam Diffraction

It is quite simple (in the transmission electron microscope) to obtain convergent-beam patterns from the surface of a bulk crystal. The beam is focussed onto the surface at near grazing incidence (figure 1) and if the surface is flat the appropriate pattern is obtained in the diffraction plane (figure 2). Such patterns are potentially valuable for the characterization of surfaces just as normal convergent-beam patterns are valuable for the characterization of crystals.There are, however, several important ways in which reflection diffraction from surfaces differs from the more familiar electron diffraction in transmission.GeometryIn reflection diffraction, because of the surface, it is not possible to describe the specimen as periodic in three dimensions, nor is it possible to associate diffraction with a conventional three-dimensional reciprocal lattice.

Extension of the Spatial PDI Model to Three Dimensions

1997 ◽  
Vol 84 (1) ◽  
pp. 176-178
Author(s):  
Frank O'Brien
Keyword(s):  
Population Density ◽  
Dimensional Space ◽  
Finite Lattice ◽  
Three Dimensional ◽  
Upper Bounds ◽  
Three Dimensions ◽  
Lower And Upper Bounds ◽  
Density Index ◽  
Three Dimensional Space

The author's population density index ( PDI) model is extended to three-dimensional distributions. A derived formula is presented that allows for the calculation of the lower and upper bounds of density in three-dimensional space for any finite lattice.

Extrusion-Based 3D Printing for Pharmaceuticals: Contemporary Research and Applications

2019 ◽  
Vol 24 (42) ◽  
pp. 4991-5008 ◽  
Author(s):  
Mohammed S. Algahtani ◽  
Abdul Aleem Mohammed ◽  
Javed Ahmad
Keyword(s):  
Cosmetic Surgery ◽  
Fused Deposition Modeling ◽  
Personalised Medicine ◽  
Organ Transplant ◽  
Three Dimensional ◽  
Dosage Forms ◽  
Release Profile ◽  
Small Scale ◽  
Drug Release Profile ◽  
Fused Deposition

Three-dimensional printing (3DP) has a significant impact on organ transplant, cosmetic surgery, surgical planning, prosthetics and other medical fields. Recently, 3 DP attracted the attention as a promising method for the production of small-scale drug production. The knowledge expansion about the population differences in metabolism and genetics grows the need for personalised medicine substantially. In personalised medicine, the patient receives a tailored dose and the release profile is based on his pharmacokinetics data. 3 DP is expected to be one of the leading solutions for the personalisation of the drug dispensing. This technology can fabricate a drug-device with complicated geometries and fillings to obtain the needed drug release profile. The extrusionbased 3 DP is the most explored method for investigating the feasibility of the technology to produce a novel dosage form with properties that are difficult to achieve using the conventional industrial methods. Extrusionbased 3 DP is divided into two techniques, the semi-solid extrusion (SSE) and the fused deposition modeling (FDM). This review aims to explain the extrusion principles behind the two techniques and discuss their capabilities to fabricate novel dosage forms. The advantages and limitations observed through the application of SSE and FDM for fabrication of drug dosage forms were discussed in this review. Further exploration and development are required to implement this technology in the healthcare frontline for more effective and personalised treatment.

scholarly journals Free partition functions and an averaged holographic duality

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Nima Afkhami-Jeddi ◽  
Henry Cohn ◽  
Thomas Hartman ◽  
Amirhossein Tajdini
Keyword(s):  
Partition Function ◽  
Spectral Gap ◽  
Central Charge ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Three Dimensions ◽  
Partition Functions ◽  
General Constraints ◽  
Dimensional Gravity ◽  
Holographic Duality

Abstract We study the torus partition functions of free bosonic CFTs in two dimensions. Integrating over Narain moduli defines an ensemble-averaged free CFT. We calculate the averaged partition function and show that it can be reinterpreted as a sum over topologies in three dimensions. This result leads us to conjecture that an averaged free CFT in two dimensions is holographically dual to an exotic theory of three-dimensional gravity with U(1)c×U(1)c symmetry and a composite boundary graviton. Additionally, for small central charge c, we obtain general constraints on the spectral gap of free CFTs using the spinning modular bootstrap, construct examples of Narain compactifications with a large gap, and find an analytic bootstrap functional corresponding to a single self-dual boson.

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