Geometric Characterization of MEMS using Spline

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Geometric Characterization of MEMS using Spline

• By
• Rohit Newaskar
• Master of Science Student
• Mechanical and Manufacturing Engineering
• Supervisor Dr. Swavik S Spiewak

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OVERV IEW

• Introduction

• MEMS ? Application

• Objectives

• Geometric Characterization of MEMS

• Proposed Algorithm

• Digital Image Processing and Spline

• Results and Applications

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MicroEletroMechanical System MEMS
INTRODUCT ION
Integration of mechanical elements, sensors,
actuators and electronics on common silicon
substrate sizes ranging from nano to micro meters.
Mirror Mechanism with a Spider Mite

• Microsystems Europe
• Micromachines Japan

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INTRODUCT ION
What is the use of micro size elements? Are
there any applications of these systems?
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INTRODUCT ION
Ink-Jet Printer Nozzles
Automobile
MEMS
BioMedical LAB ON CHIP
Digital Light Processing - DLP
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Need for Geometric Characterization
OBJECT IVE
Mechanical behavior of MEMS is important for
device design, simulation and material property
extraction.
Mechanical properties f (geometric parameters)
F
Stress f ( F,L,T)
T
L
Distance between two links centers is 50 µm.
Diameter of human hair 70 µm
Sandia micro-chain with drive gears
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Primary Objective To provide tool for efficient
geometric characterization using spline.
OBJECT IVE
Secondary Objective
Laser Doppler Vibrometer
Compact disc drive head
Comb Actuator
Auto-edge generation for defining region of
interest for LDV to minimize time consuming and
inaccurate manual boundary generation.
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Effective use of Digital Image Processing and
Spline Curves
ALGOR ITHM
Digital Image Processing

• Digitized newspaper pictures sent by submarine
  cable between London and New York in early 1920
• Used for metrology, quality control and
  non-destructive technique
• Extract useful information by processing digital
  images

Spline Curves

• From roman times to Terminator 2
• Splines can be defined as mathematical weight
  points apart from the curve which pulls the curve
  towards the points
• Reduce the resolution of curve for editing and
  transferring curve data

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Image from Camera
ALGOR ITHM
Pre processing operations
Original Image
Post processing operations
Edge data
Digital Image Processing
Generation of spline data
Converting spline data into curve
Various application
Spline Curve
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RESULTS
Section of Micro-spring with artifacts
Spline curves

• Original Edge pixel data 2818
• After Spline fitting control points - 64

Auto Edge Generation - LDV
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Interconnecting Optical Microscopy and Scanning
Probe Microscopy
APPL ICAT IONS

• Optical Microscopy
• Fast and non-contact mode of measurement
• Scope could not focus on details smaller than
  about a third of the wavelength of light being
  used.

• Scanning Probe Microscopy (SPM)
• Offers very high resolution ( 1 A )
• Lower scanning speed of probe

Look ahead function can be provided to SPM
through which will contain information of various
geometric features. Reduction in scanning time.
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Reverse Engineering of MEMS
APPL ICAT IONS
As in case of large systems such as dam or
aircrafts, first model is tested and then actual
system is build from model, same techniques can
be applied for MEMS also. For MEMS devices,
it is helpful to be able to create
geometric models directly from the
manufactured micro prototypes. This procedure,
called reverse engineering for MEMS. Efficient
geometric characterization will be useful for
compression of prototype design information.
End of Presentation
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END OF PRESENTAT ION
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