MEMS: Design and Fabrication

by Gad-el-Hak; Mohamed

• ISBN13: 9780849391385
• ISBN10: 0849391385
• Edition: 2nd
• Format: Hardcover
• Copyright: 2005-11-29
• Publisher: CRC Press

Summary

As our knowledge of microelectromechanical systems (MEMS) continues to grow, so does The MEMS Handbook. The field has changed so much that this Second Edition is now available in three volumes. Individually, each volume provides focused, authoritative treatment of specific areas of interest. Together, they comprise the most comprehensive collection of MEMS knowledge available, packaged in an attractive slipcase and offered at a substantial savings. This best-selling handbook is now more convenient than ever, and its coverage is unparalleled.The second volume, MEMS: Design and Fabrication, details the techniques, technologies, and materials involved in designing and fabricating MEMS devices. It begins with an overview of MEMS materials and then examines in detail various fabrication and manufacturing methods, including LIGA and macromolding, X-ray based fabrication, EFAB® technology, and deep reactive ion etching. This book includes three new chapters on polymeric-based sensors and actuators, diagnostic tools, and molecular self-assembly. It is a thorough guide to the important aspects of design and fabrication.MEMS: Design and Fabrication comprises contributions from the foremost experts in their respective specialties from around the world. Acclaimed author and expert Mohamed Gad-el-Hak has again raised the bar to set a new standard for excellence and authority in the fledgling fields of MEMS and nanotechnology.

Table of Contents

Preface	v
Editor-in-Chief	vii
Contributors	ix
Introduction	1	(1)
Mohamed Gad-el-Hak
Materials for Microelectromechanical Systems	1	(1)
Christian A. Zorman
Mehran Mehregany
Introduction	1	(1)
Single-Crystal Silicon	2	(1)
Polysilicon	3	(6)
Silicon Dioxide	9	(2)
Silicon Nitride	11	(3)
Germanium-Based Materials	14	(2)
Metals	16	(1)
Silicon Carbide	17	(3)
Diamond	20	(2)
III-V Materials	22	(1)
Piezoelectric Materials	22	(1)
Conclusions	23
MEMS Fabrication	1	(1)
Guangyao Jia
Marc J. Madou
Wet Bulk Micromachining: Introduction	2	(1)
Historical Note	3	(2)
Silicon Crystallography	5	(15)
Introduction
Miller Indices
Crystal Structure of Silicon
Geometric Relationships among Some Important Planes in the Silicon Lattice
Silicon as Substrate	20	(2)
Silicon as a Mechanical Element in MEMS	22	(15)
Introduction
Stress-Strain Curve and Elasticity Constants
Residual Stress in Si
Yield, Tensile Strength, Hardness, and Creep
Piezoresistivity in Silicon
Bending of Thin Si Plates
Silicon as a Mechanical MEMS Material: Summary
Other Si Sensor Properties	37	(3)
Thermal Properties of Silicon
Silicon Optical Properties
Biocompatibility of Si
Wet Isotropic and Anisotropic Etching	40	(32)
Introduction
Isotropic Etching
Anisotropic Etching
Chemical Etching Models
Etching with Bias and/or Illumination of the Semiconductor	72	(8)
Introduction
Electropolishing and Microporous Silicon
Etch-Stop Techniques	80	(11)
Introduction
Boron Etch Stop
Electrochemical Etch Stop
Photo-Assisted Electrochemical Etch Stop (for n-Type Silicon)
Photo-Induced Preferential Anodization (for p-Type Silicon)
Etch Stop at Thin Insoluble Films
Issues in Wet Bulk Micromachining	91	(9)
Introduction
Extensive Real Estate Consumption
Corner Compensation
Computer Simulation Software	100	(1)
Wet Bulk Micromachining Examples	101	(8)
Surface Micromachining: Introduction	109	(2)
Historical Note	111	(1)
Mechanical Properties of Thin Films	112	(18)
Introduction
Adhesion
Stress in Thin Films
Stress-Measuring Techniques
Strength of Thin Films
Surface Micromachining Processes	130	(15)
Basic Process Sequence
Fabrication Step Details
Control of Film Stress
Dimensional Uncertainties
Sealing Processes in Surface Micromachining
IC Compatibility
Poly-Si Surface Micromachining Modifications	145	(7)
Porous Poly-Si
Hinged Polysilicon
Thick Polysilicon
Milli-Scale Molded Polysilicon Structures
Surface Micromachining Modifications Not Involving Polysilicon	152	(9)
SOI Surface Micromachining
Resists as Structural Elements and Molds in Surface Micromachining
Comparison of Bulk Micromachining with Surface Micromachining	161	(2)
Materials Case Studies	163	(18)
Introduction
Polysilicon Deposition and Material Structure
Amorphous and Hydrogenated Amorphous Silicon
Silicon Nitride
CVD Silicon Dioxides
Metals in Surface Micromachining
Polycrystalline Diamond and SiC Films
Polysilicon Surface Micromachining Examples	181
LIGA and Micromolding	1	(1)
Guangyao Jia
Marc J. Madou
Introduction	1	(2)
LIGA --- Background	3	(6)
History
Synchrotron Orbital Radiation (SOR)
Access to the Technology
LIGA and LIGA-Like Process Steps	9	(60)
X-Ray Masks
Choice of Primary Substrate
Resist Requirements
Methods of Resist Application
Exposure
Development
Comparison of Master Micromold Fabrication Methods
Metal Deposition
Molding
Demolding
Alternative Materials in LIGA
Examples	69
X-Ray--Based Fabrication	1	(1)
Todd Christenson
Introduction	1	(3)
DXRL Fundamentals	4	(10)
X-Ray Mask Fabrication
Thick X-Ray Photoresist
DXRL Exposure (The Direct LIGA Approach)
Development
PMMA Mechanical Properties
Mold Filling	14	(6)
Material Characterization and Modification	20	(4)
Planarization	24	(1)
Angled and Reentrant Geometry	24	(2)
Multilayer DXRL Processing	26	(3)
Sacrificial Layers and Assembly	29	(1)
Application Examples	30	(16)
Conclusions	46
EFAB™ Technology and Applications	1	(1)
Ezekiel J. J. Kruglick
Adam L. Cohen
Christopher A. Bang
Introduction	1	(3)
Why EFAB?	4	(3)
Flexibility
Versatility
Accessibility
Materials
Size and Aspect Ratio
Speed
Cost
EFAB™ Technology	7	(9)
Detailed Process
Materials
EFAB™ Technology Performance
EFAB™ Technology vs. Alternative Approaches
EFAB™ Equipment
Future EFAB™ Technology Capabilities
EFAB™ Applications	16
Single-Crystal Silicon Carbide MEMS: Fabrication, Characterization, and Reliability	1	(1)
Robert S. Okojie
Introduction	1	(2)
Photoelectrochemical Fabrication of 6H-SiC	3	(5)
Characterization of 6H-SiC Gauge Factor	8	(6)
Temperature Effect on Gauge Factor
Temperature Effect on Resistance
High Temperature Metallization	14	(9)
General Experimental and Characterization Procedure
Characterization of Ti/TiN/Pt Metallization
Ti/TaSi2/Pt Scheme
Sensor Characteristics	23	(4)
Reliability Evaluation	27
Reliability by Package Design
Transducer Parametric Analysis
AST Protocol
Stability of Transducer Parameters
Long-Term Stability
Deep Reactive Ion Etching for Bulk Micromachining of Silicon Carbide	1	(1)
Glenn M. Beheim
Laura J. Evans
Introduction	1	(1)
Fundamentals of High-Density Plasma Etching	2	(1)
Fundamentals of SiC Etching	3	(2)
Applications of SiC DRIE	5
Review
Applications of SiC DRIE: Experimental Results
Applications of SiC DRIE: Fabrication of a Bulk-Micromachined SiC Pressure Sensor
Polymer Microsystems: Materials and Fabrication	1	(1)
Gary M. Atkinson
Zoubeida Ounaies
Introduction	2	(1)
Polymer Materials in MEMS	3	(14)
PVDF and Copolymers
Polyimides
Other Electroactive Polymers (PDMS, PVC, and PMMA)
Conductive Polymers
Polymer Nanocomposites
Polymer Microfabrication Techniques	17	(11)
Thin Film Deposition
Polymer Patterning Techniques
Bulk Fabrication Techniques
Assembly and Integration Techniques
Device Examples	28	(7)
Tactile Sensor and Shear Sensors in Parylene Membranes
Microfluidic Pumps and Valves Using Paraffin Actuators
Biomimetic Muscle in Polyimide Using Electrostatic Actuation
Surface Acoustic Wave Devices in Polymers
Future Directions and Challenges	35
Optical Diagnostics to Investigate the Entrance Length in Microchannels	1	(1)
Sang-Youp Lee
Jaesung Jang
Steven T. Wereley
Introduction	1	(2)
Optical Diagnostics Metrology in Microscale Fluid Mechanics	3	(5)
Pointwise Methods
Full-Field Methods
Overview of μPIV	8	(10)
Fundamental Physics Considerations of μPIV
Special Processing Methods for μPIV Recordings
Entrance Length Measurement in Microchannel Flow	18	(9)
Microchannel Fabrication
Microparticle Image Velocimetry System
Experimental Procedure
Results and Discussion
Conclusion
Extensions of the μPIV Technique	27
Microparticle Image Thermometry
Infrared μPIV
Evanescent Wave PIV
Microfabricated Chemical Sensors for Aerospace Applications	1	(1)
Gary W. Hunter
Jennifer C. Xu
Chung-Chiun Liu
Darby B. Makel
Introduction	1	(2)
Aerospace Applications	3	(3)
Leak Detection
Fire Safety Monitoring
Engine Emission Monitoring
Sensor Fabrication Technologies	6	(2)
Microfabrication and Micromachining Technology
Nanomaterials
SiC-Based High-Temperature Electronics
Chemical Sensor Development	8	(9)
Si-Based Hydrogen Sensor Technology
Nanocrystalline Tin Oxide Thin-Films for NOx and CO Detection
Electrochemical Cell Oxygen Detection
SiC-Based Hydrogen and Hydrocarbon Detection
NASICON-Based CO2 Detection
Future Directions, Sensor Arrays, and Commercialization	17	(6)
High-Selectivity Gas Sensors Based on Ceramic Membranes
Leak-Detection Array
High-Temperature Electronic Noise
Commercial Applications	23	(1)
Summary	23
Packaging of Harsh Environment MEMS Devices	1	(1)
Liang-Yu Chen
Jih-Fen Lei
Introduction	1	(1)
Material Requirements	2	(2)
Substrates
Metallization and Electrical Interconnection Systems
Die-Attach
Hermetic Sealing
Wafer-Level Packaging	4	(1)
High-Temperature Electrical Interconnection Systems	5	(8)
Thick-Film Metallization
Thick Film--Based Wire-Bond
Conductive Die-Attach
Thermomechanical Properties of Die-Attach	13	(9)
Governing Equations and Material Properties
Thermomechanical Simulation of Die-Attach
High-Temperature Ceramic Packaging Systems	22	(1)
Chip-Level Packages
Printed Circuit Board
Discussion	23
Innovative Materials
Innovative Structures
Innovative Processes
Fabrication Technologies for Nanoelectromechanical Systems	1	(1)
Gary H. Bernstein
Holly V. Goodson
Gregory L. Snider
Introduction	1	(2)
NEMS-Compatible Processing Techniques	3	(12)
Electron Beam Lithography
X-Ray Lithography
Other Parallel Nanoprinting Techniques
Achieving Atomic Resolution
Fabrication of Nanomachines: The Interface with Biology	15	(4)
Inspiration from Biology
Practical Fabrication of Biological Nanotechnology
Summary	19
Molecular Self-Assembly: Fundamental Concepts and Applications	1	(1)
Jill A. Miwa
Federico Rosei
Introduction	1	(2)
Molecule-Molecule Interactions	3	(3)
Hydrogen Bonding and van der Waals Interactions
Metal-Ligand Bonding
Molecule-Substrate Interactions	6	(7)
Adsorption of Molecules on Metal Substrates
Adsorption of Molecules on Semiconductor Surfaces
Applications of Functionalized Surfaces	13	(3)
Sensors
Functional New Materials
Conclusions and Perspectives	16
Index	1