Reporter: AGNES Purwidyantri
Student ID no: D0228005
Biomedical Engineering Dept.
What are MEMS? [1]
•Micro-Electro-Mechanical Systems (MEMS) is the integration of
mechanical elements, sensors, actuators, and electronics on a common
silicon substrate through microfabrication technology.
•Microfabrication of silicon-based structures is usually achieved by
repeating sequences of photolithography, etching, and deposition steps
•Microelectronics fabrication techniques routinely produce well-controlled
features that range in size from millimeters to submicrometers, while soft
lithography techniques were recently used to produce features below
100 nm.

Accelerometers
• (Inertial Sensors – “Crash Bags”, Navigation, Safety)


Ink Jet Print Heads
Micro Fluidic Pumps
• Insulin Pump (drug delivery)

Pressure Sensor
• Auto and Bio applications

Spatial Light Modulators (SLM’s)
• MOEM – Micro Optical Electro Mechanical Systems
• DMD – Digital Mirror Device
• DM – Deformable Mirror

Chem Lab on a Chip
• Homeland security

RF (Radio Frequency) MEMS
• Low insertion loss switches (High Frequency)

Mass Storage Devices
Typical process flow for IC manufacturing. [2]
Differences with MEMS manufacturing are in bold italics

1987 TRW NovaSensor
Accelerometer First
generation inertial
sensor Poppy seed is on
top to show scale.
Airbag3.avi
Analog Devices – 1993 Saab was the first
automobile company to include MEMS
accelerometers to trigger airbags.
Combined standard CMOS technology
with MEMS fabrication
MEMS-based systems answered the call of government regulated passive
restraints in automobiles where these systems sensed rapid deceleration
and in the event of a collision sent a signal to inflate rapidly an airbag.
 Surface
Micromachining
takes off in the 1990’s.
(Sandia National Laboratories)
This basically consists of alternating layers of structural materials (poly crystalline
silicon) and sacrificial layers (Silicon Dioxide). The sacrificial layer is a scaffold
and acts as a temporary support and spacing material. The last step of the process
is the “release” step, where the sacrificial layer is removed freeing the structural
layers so they can move.
 Micro
Optical Electro Mechanical Systems
“MEMS or Microsystems
have the potential of having a
greater impact on global
business and society than did
the computer chip.” - TI
Development started
1980’s, first commercial
product - 1996



MEMS needle within the opening of a small hypodermic needle
Smaller size reduces pain and tissue damage – now there are
much smaller MEMS needle arrays.
The plastic needle array is made through a standard MEMS
fabrication process to make the molds, micro injection process is
used to create the arrays.
Procter and Gamble
Plastic Needle Array
The Overlap between microbiology and microsystem
feature sizes makes integration between the two possible
Nucleus
Eukaryotic cells
100 µm
Ribosome
Bacteria
10 µm
Surface
Micromachinin
g Features
(MEMS)
Viruses
1 µm
Visible
Light
0.1 µm
Gate of
Leading
Edge
Transistor
Proteins
0.01 µm
(10 nm)
0.001
(1µm
nm)
Molecules
Atom













Lab on a chip/ smart prosthesis
Advantages:
Biocompatability
Greater reproducibility+reliability
Miniaturized implants
Rapid
Ability to provide electrical stimulus
Chemical functionalization (tissue eng)
Miniaturized
Low cost
Integration of sensor, actuators and electronics
Interaction with fluids (microfluidics TAS,
biochemical sensors)
etc
•A
large variety – difficult to classify
• Patient viewpoint:
– diagnostic microsystems: rapid point-of-care, systems on a chip,
cell and molecule sorting, DNA diagnostics
– surgical microsystems: MIS (minimally invasive surgery),
CADassisted surgery - microrobotics
– therapeutic microsystems + prostheses: drug and gene delivery,
tissue augmentation/repair, biocapsules, micro/minimally invasive
surgical systems
• The scale of the application: body level (drug delivery,
tools for microsurgery, pacemakers, neural probes), analysis of
body fluids (“Lab-on-a-chip” for blood analysis, glucose
monitoring, electrophoresis), tissue and cell analysis, genomics
(DNA microarrays) and proteomics (protein identification and
characterization)
• Biggest promise: better outcome for the patient and a lower
overall health and cost
Micro Total Analysis System
•Micro ELISA
•Micro FACS
•Micro mass-spectrometer
Micro Biomedical System
•Micro syringe
•Micro CSF shunt
•Drug delivery bio-chip
•Immunosensing bio-chip
•Micro cell chip
MEMS cantilevers as biosensors [3]
Gold dot = 40nm
SiN thickness = 90nm
By changing the coating
(Nano) one can functionalize
the cantilever to detect
single strands of DNA.
Mass resolution is on the
order of under 1 ato gram
(10-18grams)
5 x 15um Cantilever with an
E. Coli cell bound to immobilized
antibody layer.
Black is the response before cell attachment,
Red is after cell attachment.
School of Applied and Engineering Physics and the
Nanobiotechnology Center, Cornell University
MEMS cantilevers as biosensors
Origin of nanomechanical cantilever motion generated from
biomolecular interactions:
Bio-MEMS Polymer/Si Cantilevers
Sensors [7]
References
1.
2.
3.
4.
5.
6.
7.
Grayson A.C. R et al. 2004. A BioMEMS Review: MEMS Technology
for Physiologically Integrated Devices. Invited Paper. IEEE
Proceeding 92 (1).
Vemal, R., Lo, C., Ong, S., Lee, B. S and Yong, C. C. 2009. MEMS vs. IC
Manufacturing: Is Integration Between Processes Possible.1st Int'l
Symposium on Quality Electronic Design-Asia. IEEE 2009
Hubler, U et al. 2003. Reprint from BioWorld
http://www.hgc.cornell.edu/Nems%20Folder/Enumeration%20of
%20Single%20DNA.html
http://www.news.cornell.edu/releases/April04/attograms.ws.html
Kristein, K. U et al. Cantilever-Based Biosensors in CMOS
Technology. Physical Electronics Laboratory, ETH Zurich,
Switzerland.
Hit, Z. et al. 2002. Applied Physics Letters 81 (16): 3091-3093.
Thank You