category » MEMS & BioMEMS

Figure 2:  A microphotograph of a patterned samarium cobalt magnetic thin film.  The abilities first to sputter-deposit and second to wet-etch thin films like this is critical to the successful implementation of magnetic self-assembly and are unique strengths of the MIT/Queens College effort.
Magnetically-assisted Assembly, Alignment, and Orientation of Micro-scale Components
  • The use of magnetic forces to improve fluidic self-assembly of micro-components has been investigated using Maxwell 3D to model the…


Batch-Microfabricated RPA for Ion Energy Measurements
  • Plasma diagnostic tools are required in numerous fields, from experimental physics to aerospace and beyond.  Various sensors exist to capture…


Electro-chemical Stimulation of Neuromuscular Systems Using Ion-selective Membranes
  • Spinal cord injury (SCI) leads to paralysis, decrease in quality of life, and high lifetime medical costs. Direct nerve functional…


Figure 1: (a) The 4T NEM relay and its operating states, (b) a 6-bit relay multiplier built with full and half adders, and (c) an alternative design built with (7:3) and smaller compressors.
Designing Complex Digital Systems with Scaled Nano-electro-mechanical Relays
  • Silicon CMOS circuits have a well-defined lower limit on their achievable energy efficiency due to sub-threshold leakage. Once this limit…


Figure 2: Cross-sectional SEM of an example metal-organic-metal structure formed with an evaporated Au bottom electrode, self-assembled poly(ethylene glycol) dithiol organic layer, and nanotransfer printed Au top electrode.
Tunneling Nanoelectromechanical Switches Based on Organic Thin Films
  • With the silicon-based electronics reaching physical limits that inhibit continued improvements in device performance, much research has been directed towards…


Figure 1: (a) The illustration of multiplexed all-electronic biosensors; (b) The illustration of one element of the sensor; and (c) The cross-section of one element.
Microfluidic Electronic Detection of Protein Biomarkers
  • Immunoassays use antibodies to detect protein biomarkers, with a substantial global market and significant importance for clinical practice. However, traditional…


Micron- and Submicron-thick Parylene Substrates for Transfer Printing and Solar Applications
  • Transfer printing of thin metal films enables the fabrication of both planar and suspended membrane electrodes for microelectromechanical (MEMS) sensors…


Figure 1 Fabricated nonlinear resonance based energy harvester.
Wide-bandwidth, Low-frequency, Low-g Piezoelectric MEMS Energy Harvesters
  • Our group proposes the piezoelectric energy harvester based on a nonlinear resonator to address the narrow bandwidth issue of conventional…


Figure 1: Photographs of the sintered rare-earth oxide pellets (cerium oxide through lutetium oxide). All the pellets are hydrophobic: water contact angles range between 100° and 115°. The image at the center is a goniometer snapshot of a water droplet beading up on a smooth neodymium oxide surface, as a model sample of the entire REO series; scale bar is 1 mm.
Hydrophobic Rare-earth Oxide Ceramics with Applications to Sustained Dropwise Condensation
  • Hydrophobic materials that are robust to harsh environments are needed in a broad range of applications[1][2][3]. Although durable materials such…


Figure 2: Plot of the change in voltage drop across one half of the sensor versus the change in voltage drop across the other half of sensor for application of pressure and two directions of shear. The appearance of points for each type of deformation in different quadrants of the plot demonstrates that the sensor can separate pressure and shear. Note that this preliminary data was generated under specific conditions on a single sensor.
Stretchable Pressure- and Shear-sensing Skin Printed from PDMS
  • In the fields of robotics and prosthesis design, there is need for inexpensive, wide-area pressure- and shear-sensing arrays that can…


Figure 2: Simulation and experimental demonstration of tilting pillars. a) Finite element (Abaqus) simulation of tilt angle when h=80μm d=26μm, field is 0.7 Tesla at 60°. Legend represents the strain. b) Simulation result of tilt angle as a function of field. Square symbol shows experimentally demonstrated result. c) Time-lapse side view image of a sample with field of ~0.5 Tesla at ~60°. d) Time-lapse top view image of a sample with field of~0.5 Tesla at ~60°.
Design and Fabrication of Magnetically Tunable Microstructured Surfaces
  • Micro- and nanostructured surfaces have broad applications ranging from liquid transport in microfluidics and cell manipulation in biological systems to…


Figure 1:  A scanning electron micrograph of six ten-probe line-ar arrays assembled into a six-by-ten two-dimensional array of probes.  The probes in this figure and in Figure 2 were fab-ricated for assembly studies and lack sense electrodes.  Each needle is 3.5 mm long and 40 µm wide at the tip.
Scalable 3-D Microelectrode Recording Architectures for Charac-terization of Optogenetically Modulated Neural Dynamics
  • Optogenetics is commonly used for precision modulation of the activity of specific neurons within neural circuits[1], but assessing the impact…


Figure 1:  (a) A photomicrograph of a linear array of five waveguide probes, each which has nine guides.  (b) An SEM micrograph of a 2-D probe array assembled from four linear arrays having five waveguide probes, each of which has twelve guides.  (c) A zoomed-in view of the 2-D array in Figure 1b showing the 45˚ mirrors and output ports.  The scale bars are all 100 µm long.
Waveguide Micro-probes for Optical Control of Excitable Cells
  • Optogenetics is the safe, effective delivery of light-gated membrane proteins to neurons and other excitable cells (e.g., muscle, immune cells,…


Figure 2: Aligned-CNT nano-engineered composite macro-scale architectures, nanostitching (a) and fuzzy fiber (b).
Aligned CNT-based Microstructures and Nano-engineered Composite Macrostructures
  • Carbon nanotube (CNT) composites are promising new materials for structural applications thanks to their mechanical and multifunctional properties. We have…


Figure 1: Left: microfluidic device containing a forest of carbon nanotubes through which fluids pass.  Center top: a confocal microscope image of the nanotube forest after the nanotube trees have been individually coated uniformly with molecular layers of polymers containing green fluorescent dye.  Right: Scanning and transmission electron microscope (SEM and TEM) images of the nanotube forest edge.  Center Bottom:  TEM image showing an individual nanotube coated conformally with the polymer layers.
Nanoporous Elements with Layer-by-layer Assembly in MEMS with a Focus on Microfluidic Bioparticle Separation
  • We have integrated ultra-porous (99% porous) elements (nanoporous forests of vertically aligned carbon nanotubes (VACNTs)) in MEMS, showing their use…


Figure 1: Schematic of two MEMS tactels (one fully actuated and another fully relaxed), showing the piezo actuators (red), displacement amplifiers (light blue), pins (deep blue), and cap plate (gray).
MEMS-enabled Tactile Displays for the Blind and Visually Impaired
  • According to the World Health Organization, more than 285 million people have visual impairments worldwide, and 39 million of those…


Figure 1: Scanning electron micrographs (top) and schematic (bottom) of unreleased deep trench (DT) MEMS resonator. Acoustic Bragg reflectors (ABRs) formed from periodically spaced DTs define a high-Q resonant cavity in the center of the device. DT capacitors inside the resonant cavity form electrostatic drive and sense transducers.
Deep Trench Capacitor Drive of Unreleased Si MEMS Resonator
  • With frequency-quality factor products (f•Q) often exceeding 1013, MEMS resonators offer a high-Q, small footprint alternative to conventional LC tanks…


Fabrication flow of underwater pressure sensor array.
Development of Porous Piezoresistive Materials and Its Applications for Underwater Pressure Sensors and Tactile Sensors
  • Microelectromechanical system (MEMS) pressure sensor arrays are gaining attention in the field of underwater navigation because they are seen as…


Figure 2: Device performance on blood sample. (A) Single pass recovery percentage of blood components for sample collected from inner outlet at different hematocrits. (B) Comparison of PMN activation by spiral and other RBC removal techniques, including density centrifugation  (MP-RM) and RBC lysis, based on flow cytometry analysis of CD66b+ CD18+ cells.
Continuous RBC Removal Using Spiral Channel with Trapezoidal Cross-section
  • Red blood cells (RBC) are the most abundant cell component in many biological fluids, including blood, bone marrow aspirate, and…


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Mechanisms for Intrinsic Stress Evolution during Deposition of Polycrystalline Films
  • Complex kinetic processes are involved during the growth of polycrystalline films, which is typically carried out far from equilibrium. Minor…


Figure 2: Simulation results of the second kind of continuation results. The blue curve shows that pull-in happens at 2.683V; the red curve shows that lift-off happens at 2.442 V.
MEMS Pull-in and Lift-off Simulation Using Continuation Methods
  • The voltages at which MEMS actuators and sensors become unstable, known as pull-in and lift-off voltages, are critical parameters for…


Figure 2: Damage inspection of a model bolt-hole composite joint. Voltage (0.16 and 12.3 V) was applied directly through hand-held probes to induce heating.
Preventing Catastrophic Failures: Nano-engineered Multi-physics Materials for Structural Applications
  • Catastrophic structural failures cause many physical and personal losses, with prevention estimated at billions of dollars in savings each year….


Figure 2: Fabricated pMUT chip.  Columns form 1D device arrays.  Inset: Top view microscope image of completed pMUT.
Thin Film Piezoelectric Micro-machined Ultrasonic Transducer for Medical Imaging
  • Ultrasound is an attractive 3D medical imaging technique because it is relatively inexpensive, portable, compact, and non-invasive. However, for 3D…


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Erythrocyte Deformability Correlates to Intracellular Calcium Level
  • Elevated intracellular calcium level ([Ca++]i) and reduced deformability  in red blood cells (RBCs) are commonly associated with blood-related diseases[1][2][3] as…


Figure 1: Streptavidin-functionalized polystyrene microspheres are coated with two layers of protein; the first via the streptavidin−biotin interaction and the second via antibody−antigen binding. Particle populations were measured in a solution just below the bulk density of the core microspheres and are plotted at an equivalent solution density. The protein layers add 9.8 and 6.5 fg of buoyant mass, respectively; equivalent to approximately 150 and 100 ng/cm2 absolute mass, assuming a protein density of 1.35 g/cm3.
Quantifying Particle Coatings Using High-precision Mass Measurements
  • Microparticles are currently used in a variety of industrial and biomedical applications and are often coated with different materials to…


Figure 1: The SEM images of carbon nanotubes percolation network with different pitch sizes.
Thermal Ink Jet Printing of CNT films
  • Ink jet printing allows for rapid, scalable, and low-cost patterning process. It does not need a vacuum environment or toxic…


Figure 1: Top and 3D views of a Si-based NEMS-CMOS.
Automated Parameterized Dynamical Modeling of RF MEMS Resonators
  • Design and optimization of novel RF micro-electro-mechanical system (MEMS) resonators such as resonant body transistors (RBT) require modeling across multiple…


Figure 2: Optical interferometry images of several cavities under 15 V peak-to-peak amplitude sinusoidal voltage actuation at 15 Hz, taken at 30 degree phase intervals. Membrane deflection for only one half of a sine wave is shown in this figure.
Contact-printed MEMS Membranes
  • It is desirable to extend the functionality of MEMS to different form factors including large-area arrays of sensors and actuators,…


Figure 1: (a) 2DEG confined in conduction band potential well at the interface between AlGaN and GaN. (b)  Principle of switchable piezoelectric transduction. (c) SEM of piezoelectric-drive, HEMT-sensed resonator.
Switchable Piezoelectric Transduction in AlGaN/GaN MEMS Resonators
  • High-Q MEMS resonators, with small footprint and monolithic integration, are excellent building blocks for configurable RF systems. While these resonators…


Figure 1: Iso-dielectric separation (IDS) microfluidic device used to measure electrical properties of the cells. The spatial conductivity gradient makes cells with different electrical properties pass through the electrodes at different positions (isodielectric point - IDP).
Iso-dielectric Separation of Cells and Particles
  • The development of new techniques to separate and characterize cells with high throughput has been essential to many of the…


Figure 1: Image of the synchronization device illuminated from the backside, showing branching fluidic channels that lead into a cell capture chamber with 2109 2-mm diameter holes onto which cells can be loaded. In the schematic diagram, the side view illustrates the cross section along the dotted line in the top view. The channels are etched into the top glass wafer, and the 2-mm holes and fluidic ports are etched into the bottom SOI wafer.
A Microfluidic ‘‘Baby Machine’’ for Cell Synchronization
  • Common techniques used to synchronize eukaryotic cells in the cell cycle often impose metabolic stress on the cells or physically…


Figure 2: 3×3 array of 5-mm tall emitters producing PEO nanofibers in the stable regime.
High-throughput Electrospinning of Nanofibers from Batch-microfabricated Arrays
  • Nanofibers’ unique morphological properties promise to make them a key engineering material across many disciplines.  In particular, the large specific…


Figure 1: Current-voltage characteristics of AlGaN/GaN membranes with HFSiN and LFSiN passivation layers on the top surface. The insets show pictures of the different processed chips.
Impact of SiNx Passivation on IDS,max of AlGaN/GaN HEMTs
  • Dielectric films such as SiNx, SiO2, and Al2O3 play key roles in AlGaN/GaN heterostructure field-effect transistors (HFETs) both as surface…


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Cell Pairing for Studying Immunity
  • Cell-cell interactions are crucial for proper functioning of the immune system because direct cell-cell contacts largely govern the successful progression…


Figure 1: (a) Side-view schematic of axon diode, (b) Fluorescent false-colored image of a 12-DIV neuronal network configured by the axon-lock system. The plain arrows represent the direction of the diode. (c) Images of axon diode chip showing three microchambers and electrodes.
Electrokinetic Control of Axonal Growth
  • Dynamic control of axonal outgrowth holds the potential to establishing a range of in-vivo and in-vitro applications including perpiheral nerve…


Figure 1: Schematic illustration of the (A) 3-channel margination microdevice and (B) separation principle at each bifurcation stage. Deformable RBCs migrate axially to the channel center, resulting in margination of other cell types (bacteria, platelets and leukocytes) towards the channel sidewalls while the center outlet collects the bacteria-depleted blood.
A Novel Microfluidic “Cell-based” Blood Dialysis Platform for Septic Murine Model
  • Sepsis is an adverse systemic inflammatory response caused by microbial infection in blood. We have reported a microfluidic approach for…