Case Studies in Micromechatronics: From Systems to Processes

Preface
Contents
1 Introduction
	1.1	Mechatronic Systems
	1.2	A Brief History of Micromechatronics
		1.2.1	Integrated Circuits
		1.2.2	Piezoresistivity
		1.2.3	Silicon Bulk Micromachining
		1.2.4	LIGA
		1.2.5	Surface Micromachining
		1.2.6	Soft Lithography and Lab-on-Chip Systems
		1.2.7	Direct Micromachining
		1.2.8	The Future
	1.3	Overview of Microfabrication Methods
	1.4	Applications and Markets
	1.5	Topics of the Addressed Case Studies
	1.6	Summary
	References
2 Piezoresistive Pressure Sensors
	2.1	Applications of Pressure Sensors
		2.1.1	Atmospheric Pressure Measurement
		2.1.2	Automotive Industry
		2.1.3	Flow Measurements in Aircraft Research
	2.2	Design and Fabrication of Piezoresistive Pressure Sensors
		2.2.1	Basics
		2.2.2	Functional Principle of Piezoresistive Pressure Sensors
		2.2.3	Silicon Wafer Fabrication and Crystallography of Single-Crystal Silicon
		2.2.4	Electrical Properties of Single-Crystal Silicon and Doping
		2.2.5	Piezoresistive Effect of Doped Single-Crystal Silicon
		2.2.6	Sensor Design
	2.3	Exemplary Fabrication Process of the Silicon Membrane Device as Part of a Piezoresistive Pressure Sensor
	2.4	Excursus: Lithography
	2.5	Summary
	References
3 Surface Micromachined Acceleration Sensors
	3.1	Accelerometer Applications
		3.1.1	Inertial Navigation Systems
	3.2	Design and Functional Principles of Acceleration Sensors
		3.2.1	Accelerometer Basics
		3.2.2	Acceleration Sensor Designs
		3.2.3	Multi-Axis Designs
		3.2.4	Capacitance Detection Circuits
		3.2.5	Closed-Loop Accelerometers
	3.3	Surface Micromachining
		3.3.1	Basic Sacrificial Layer Processing
		3.3.2	Surface Micromachined Devices
	3.4	Deep Reactive Ion Etching (DRIE)
	3.5	Process Chain for the Fabrication of a Surface Micromachined Accelerometer
	3.6	Thin Film Deposition
		3.6.1	Physical Vapor Deposition (PVD)
		3.6.2	Chemical Vapor Deposition (CVD)
		3.6.3	Non Vacuum Deposition Techniques
	3.7	Excursus: Further Sensor Principles and Characteristics
		3.7.1	Sensor Classification Schemes
		3.7.2	Static and Dynamic Sensor Characteristics
	3.8	Summary
	References
4 Mechanical Microgrippers
	4.1	Applications of Microgrippers
		4.1.1	Handling Technology and 3D Micropart Assembly
		4.1.2	In-Liquid Living Cell Handling and Manipulation
		4.1.3	Minimally Invasive Surgeries
		4.1.4	Investigation of Multi-Axial Stress States of Skeletal Muscle Tissue
	4.2	Design and Functional Principles of Mechanical Microgripers
	4.3	Materials
		4.3.1	Silicon
		4.3.2	Su-8
		4.3.3	Cyclic Olefin Copolymers (COC)
		4.3.4	Further Suitable Materials
	4.4	Fabrication Methods
		4.4.1	Silicon Bulk Technique: ICP-DRIE
		4.4.2	UV Depth Lithography
		4.4.3	Microinjection Molding MIM
		4.4.4	Further Fabrication Methods
	4.5	Actuation Principles
		4.5.1	Definition of an Actuator
		4.5.2	Classification of Actuation Principles
		4.5.3	Scaling Laws
		4.5.4	Comparison of Microactuation Principles
		4.5.5	Shape Memory Actuation Principle
		4.5.6	Pneumatic Actuation Principle
		4.5.7	Further Microactuation Principles
	4.6	Further Microgripper Components and All-in System
		4.6.1	Design of the Microgripper Gear
		4.6.2	Gripping Force Sensing Principle
		4.6.3	Mechanical Microgrippers Actuated by SMA Actuator Elements and Pneumatically
	4.7	Exemplary Fabrication Process of the Pneumatically Actuated SU-8 Microgripper
	4.8	Excursus: Further Microactuator Systems
		4.8.1	Electromagnetic Micropump for Biomedical Microfluidic Systems
		4.8.2	Bistable Microvalve
		4.8.3	Membrane-Type Micropump with Passive Silicon Microvalve
	4.9	Summary
	References
5 Point-of-Care Diagnostic Systems
	5.1	Applications of Point-of-Care Diagnostic (POCD) Systems
		5.1.1	Antigen-Based POCD Systems
		5.1.2	POCD Against Antibiotic Resistance
		5.1.3	Application of POCDs in the Developing World—Malaria
		5.1.4	Working Principle of Antigen-Based Lateral Flow Immunoassays
		5.1.5	Application of POCDs in Self-Diagnosis—the Pregnancy Test
		5.1.6	Application of POCDs in Self-Testing and Disease Management—Glucose Meter
		5.1.7	Application of POCDs in Primary Care—Streptococcal Pharyngitis
		5.1.8	Molecular POCD Systems
		5.1.9	Application of POCDs in Personalized Medicine—C-Reactive Protein (CRP)
	5.2	Microfluidics—The Basics
		5.2.1	Brief Introduction
		5.2.2	What is a Fluid?
		5.2.3	Viscosity
		5.2.4	Reynolds Number and Flow Regimes
		5.2.5	Laminar and Turbulent Flow
		5.2.6	Other Dimensionless Parameters
		5.2.7	More about Diffusion
		5.2.8	Surface Tension and Wetting
		5.2.9	Resistance to Flow
		5.2.10	Stokes Flow
	5.3	Microfluidic Components for Active Flow Control
		5.3.1	Microchannels
		5.3.2	Microfluidic Valves
		5.3.3	Micropumps
		5.3.4	Microfluidic Mixers
		5.3.5	Microfluidic Sample Separation
	5.4	Soft Lithography
		5.4.1	Micro-Contact Printing
		5.4.2	Microtransfer Molding
		5.4.3	Micromolding in Capillaries
		5.4.4	Micro-Replica Molding
		5.4.5	Nanoimprint Lithography
		5.4.6	Solvent-Assisted Micromolding
	5.5	Quartz Technology
		5.5.1	Quartz Crystal
		5.5.2	Production of Synthetic Quartz
		5.5.3	Properties of Single Crystal Quartz—Anisotropy
		5.5.4	Piezoelectric Properties of Quartz
		5.5.5	Crystal Oscillators—Quartz Crystal Microbalance
		5.5.6	Miniaturization of QCMs
	5.6	Laser Micromachining
		5.6.1	Lasing
		5.6.2	Stimulated Emission
		5.6.3	Population Inversion
		5.6.4	Laser Operation
		5.6.5	Types of Lasers
		5.6.6	Pulsed Laser Ablation (PLA)
		5.6.7	Two-Photon Polymerization (2PP)
	5.7	Fabrication Chain of a POCD System for the Detection of CRP
		5.7.1	Fabrication of QCM
		5.7.2	Master Wafer Fabrication and the Production of the Microfluidic Channels
		5.7.3	Assembly of QCM Sensor for the Detection of CRP
	5.8	Excursus: Microbioreactors
	5.9	Summary
	References
6 Flexible and Stretchable Sensor Arrays
	6.1	Applications of Flexible and Stretchable Sensor Arrays
	6.2	Design, Materials and Fabrication Strategies
	6.3	Process Chain for the Fabrication of a Flexible Sensor Array
	6.4	Excursus: Cleanroom Technology
		6.4.1	Defects and Yield
		6.4.2	Cleanroom Design
		6.4.3	The Human Factor in Cleanrooms
		6.4.4	Process Liquids and Gases
		6.4.5	Advanced Cleanroom Concepts
	6.5	Summary
	References
Index