Huff Process Variations in Microsystems Manufacturing

1. Auflage 2020
ISBN: 978-3-030-40560-1
Verlag: Springer International Publishing
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 531 Seiten

Reihe: Microsystems and Nanosystems

This book thoroughly examines and explains the basic processing steps used in MEMS fabrication (both integrated circuit and specialized micro machining processing steps. The book places an emphasis on the process variations in the device dimensions resulting from these commonly used processing steps. This will be followed by coverage of commonly used metrology methods, process integration and variations in material properties, device parameter variations, quality assurance and control methods, and design methods for handling process variations. A detailed analysis of future methods for improved microsystems manufacturing is also included. This book is a valuable resource for practitioners, researchers and engineers working in the field as well as students at either the undergraduate or graduate level.

Michael A. Huff, Ph.D., is Founder and Director of the MEMS & Nanotechnology Exchange (MNX) in Reston, Virginia. The MNX was established as a national-level program to provide access to MEMS implementation resources as well as to develop manufacturing techniques to help advance the technology. Dr. Huff has actively participated in MEMS research and development for over twenty-five years, has published numerous papers on MEMS devices and fabrication technologies, and holds more than a dozen patents and has several others pending. He has held a variety of notable positions, from industry to academia. Prior to establishing the MNX, Dr. Huff was on the faculty in the Department of Electrical Engineering at Case Western Reserve University (CWRU) in Cleveland, Ohio. Before joining the faculty at CWRU, he held the position of Technical Fellow at the Baxter Healthcare Corporation and directed Baxter's corporate-wide efforts in applying MEMS technology to novel medical devices. Dr. Huff received an M.S. in Electrical Engineering and Computer Science and simultaneously the M.S. in Material Science and Engineering with a specialization in Electronic Materials and a Ph.D. in Electrical Engineering and Computer Science from the Massachusetts Institute of Technology. 

Autoren/Hrsg.

Huff, Michael

Inhaltsverzeichnis

1;Preface;7
2;Acknowledgments;10
3;Contents;11
4;Chapter 1: Introduction;18
4.1;1.1 From Vacuum Tubes to Microsystems;18
4.2;1.2 MEMS Microsystems;19
4.3;1.3 Some of the Important Attributes of MEMS Microsystems;21
4.4;1.4 Organization of This Book;23
4.5;References;25
4.6;Other Information;25
5;Chapter 2: An Overview of MEMS Microsystems;26
5.1;2.1 Introduction;26
5.2;2.2 Microsensors and Microactuators;26
5.2.1;2.2.1 MEMS Microsensors;27
5.2.1.1;2.2.1.1 Resistive;27
5.2.1.2;2.2.1.2 Piezoresistive;29
5.2.1.3;2.2.1.3 Capacitive;30
5.2.1.4;2.2.1.4 Piezoelectric;32
5.2.1.5;2.2.1.5 Tunneling;33
5.2.1.6;2.2.1.6 Magnetic;35
5.2.1.7;2.2.1.7 Photoconduction;36
5.2.1.8;2.2.1.8 Thermoelectric;37
5.2.1.9;2.2.1.9 Diodes;38
5.2.2;2.2.2 MEMS Microactuators;40
5.2.2.1;2.2.2.1 Electrostatic;40
5.2.2.2;2.2.2.2 Piezoelectric;41
5.2.2.3;2.2.2.3 Thermal;43
5.2.2.4;2.2.2.4 Shape-Memory Alloys (SMA);44
5.2.2.5;2.2.2.5 Magnetic;45
5.3;2.3 Microsystems Manufacturing Processes;47
5.4;2.4 Batch Fabrication;49
5.5;2.5 Some Basics of Microsystems Manufacturing;51
5.5.1;2.5.1 Differences Between IC and MEMS Manufacturing;52
5.5.2;2.5.2 Microsystems Feature Sizes;54
5.6;2.6 Some Material Basics Regarding Semiconductors and Silicon;55
5.7;2.7 Summary;60
5.8;References;60
6;Chapter 3: Microsystems Manufacturing Methods: Integrated Circuit Processing Steps;62
6.1;3.1 Introduction;62
6.2;3.2 Basic IC Processing Steps;64
6.2.1;3.2.1 Thin-Film Growth and Deposition Techniques;64
6.2.1.1;3.2.1.1 Thermal Oxidation;64
6.2.1.2;3.2.1.2 Chemical Vapor Deposition;69
6.2.1.2.1;3.2.1.2.1 Atmospheric Chemical Vapor Deposition (ACVD);72
6.2.1.2.2;3.2.1.2.2 Low-Pressure Chemical Vapor Deposition (LPCVD);73
6.2.1.2.3;3.2.1.2.3 Plasma-Enhanced Chemical Vapor Deposition (PECVD);75
6.2.1.2.4;3.2.1.2.4 Atomic Layer Deposition (ALD);77
6.2.1.3;3.2.1.3 Physical Vapor Deposition (PVD);79
6.2.1.3.1;3.2.1.3.1 Evaporation;79
6.2.1.3.2;3.2.1.3.2 Sputtering;82
6.2.2;3.2.2 Impurity Doping;84
6.2.2.1;3.2.2.1 Thermal Diffusion;85
6.2.2.2;3.2.2.2 Ion Implantation;88
6.2.3;3.2.3 Photolithography;93
6.2.4;3.2.4 Rapid Thermal Anneal (RTA);98
6.2.5;3.2.5 Planarization;100
6.2.6;3.2.6 Etching;102
6.2.7;3.2.7 Clean and Strip;109
6.3;3.3 Summary;110
6.4;References;111
7;Chapter 4: Microsystems Manufacturing Methods: MEMS Processes;115
7.1;4.1 Introduction;115
7.2;4.2 MEMS Substrate Material Types;116
7.3;4.3 MEMS Materials Deposition Processing Steps;117
7.3.1;4.3.1 MEMS Thin-Film Materials Deposited on IC Equipment;117
7.3.1.1;4.3.1.1 Thin-Film Semiconductors;117
7.3.1.1.1;4.3.1.1.1 Silicon (Si);117
7.3.1.1.2;4.3.1.1.2 Silicon-Germanium (SiGe);119
7.3.1.1.3;4.3.1.1.3 Germanium (Ge);120
7.3.1.1.4;4.3.1.1.4 Silicon Carbide (SiC);120
7.3.1.1.5;4.3.1.1.5 Diamond;121
7.3.1.2;4.3.1.2 Metals;122
7.3.1.3;4.3.1.3 Thin-Film Metal Oxides;124
7.3.1.4;4.3.1.4 Dielectrics;125
7.3.1.4.1;4.3.1.4.1 Silicon Nitride (SiN);125
7.3.1.4.2;4.3.1.4.2 Silicon Dioxide (SiO2);126
7.3.1.5;4.3.1.5 Polymers;127
7.3.1.5.1;4.3.1.5.1 SU-8;127
7.3.1.5.2;4.3.1.5.2 PDMS;128
7.3.1.5.3;4.3.1.5.3 Polyimide;128
7.3.1.6;4.3.1.6 Ceramics;129
7.3.1.7;4.3.1.7 Special MEMS Materials;130
7.3.1.7.1;4.3.1.7.1 Piezoelectric Materials;130
7.3.1.7.2;4.3.1.7.2 Shape-Memory Alloys (SMAs);132
7.3.1.7.3;4.3.1.7.3 Magnetic Materials;133
7.3.2;4.3.2 MEMS Specific Processing Steps;134
7.3.2.1;4.3.2.1 Electrochemical Deposition;134
7.3.2.2;4.3.2.2 MEMS Lithography;136
7.3.2.2.1;4.3.2.2.1 Contact Photolithography;137
7.3.2.2.2;4.3.2.2.2 Front-to-Back Contact Photolithography;137
7.3.2.2.3;4.3.2.2.3 Direct-Write Laser Photolithography;138
7.3.2.2.4;4.3.2.2.4 Grayscale Photolithography;138
7.3.2.2.5;4.3.2.2.5 X-Ray Lithography;140
7.3.2.2.6;4.3.2.2.6 E-Beam Lithography;140
7.3.2.2.7;4.3.2.2.7 Lithography on Large Topography;141
7.3.2.2.8;4.3.2.2.8 Lift-Off Patterning;142
7.3.2.2.9;4.3.2.2.9 Image Reversal Photoresists;143
7.3.2.2.10;4.3.2.2.10 Photolithography on Transparent Substrates;144
7.4;4.4 MEMS Micromachining Methods;144
7.4.1;4.4.1 Bulk Micromachining;145
7.4.1.1;4.4.1.1 Wet Chemical Etchants;145
7.4.1.1.1;4.4.1.1.1 Isotropic Wet Chemical Etchants;146
7.4.1.1.2;4.4.1.1.2 Anisotropic Wet Chemical Etchants;147
7.4.1.2;4.4.1.2 Gas-Phase Isotropic Chemical Etchants;153
7.4.1.3;4.4.1.3 Deep Reactive Ion Etching (DRIE) of Silicon;154
7.4.1.4;4.4.1.4 Deep, High-Aspect Ratio RIE of Fused Silica, Quartz, and Glass;157
7.4.1.5;4.4.1.5 Deep, High-Aspect Ratio RIE of Silicon Carbide (SiC);159
7.4.2;4.4.2 Surface Micromachining;160
7.4.3;4.4.3 Wafer Bonding;163
7.4.4;4.4.4 LIGA;166
7.4.5;4.4.5 Hot Embossing;168
7.4.6;4.4.6 Other MEMS Micromachining Technologies;169
7.4.6.1;4.4.6.1 Electro-Discharge Micromachining;169
7.4.6.2;4.4.6.2 Laser Micromachining;169
7.4.6.3;4.4.6.3 Focused Ion Beam (FIB) Micromachining;170
7.4.6.4;4.4.6.4 Electrochemical Fabrication (EFAB);171
7.5;4.5 Summary;171
7.6;References;173
8;Chapter 5: Metrology for Microsystems Manufacturing;188
8.1;5.1 Introduction;188
8.2;5.2 Fabrication Metrology Equipment and Methods;189
8.2.1;5.2.1 Optical Microscopy;189
8.2.2;5.2.2 Fluorescence Microscopy;192
8.2.3;5.2.3 Confocal Microscopy;194
8.2.4;5.2.4 Stereomicroscopy;195
8.2.5;5.2.5 Scanning Electron Microscope (SEM);195
8.2.6;5.2.6 Automated Scanning Electron Microscope;198
8.2.7;5.2.7 Thin-Film Thickness;200
8.2.7.1;5.2.7.1 Interferometry;200
8.2.7.2;5.2.7.2 Ellipsometry;202
8.2.7.3;5.2.7.3 Stylus Profilometry;204
8.2.8;5.2.8 Four-Point Probe;206
8.2.9;5.2.9 Thin-Film Stress Measurement;208
8.2.10;5.2.10 Particle Measurements;212
8.2.11;5.2.11 Noncontact Optical Profilometry;213
8.2.12;5.2.12 Wafer Bonding Inspection;215
8.3;5.3 Specialized Metrology Equipment and Methods;218
8.3.1;5.3.1 Focused Ion Beam;218
8.3.2;5.3.2 Scanning Tunneling Microscopy (STM);221
8.3.3;5.3.3 Atomic Force Microscopy (AFM);223
8.3.4;5.3.4 Energy-Dispersive X-Ray Spectroscopy (EDXS);225
8.4;5.4 Highly Specialized Material Analysis Methods;227
8.5;5.5 Electrical Material Properties Test Methods;232
8.5.1;5.5.1 Junction Depth Measurements;232
8.5.2;5.5.2 Spreading Sheet Resistance;233
8.6;5.6 Summary;236
8.7;References;238
9;Chapter 6: Microsystems Material Properties;241
9.1;6.1 Introduction;241
9.2;6.2 Residual Stress and Young´s Modulus;243
9.2.1;6.2.1 Young´s Modulus;244
9.2.2;6.2.2 Residual Stress;246
9.3;6.3 Mechanical Test Structures;248
9.3.1;6.3.1 Test Structures for Young´s Modulus;248
9.3.2;6.3.2 Thin-Film Residual Stress Test Structures;251
9.3.3;6.3.3 Stress Gradients;255
9.3.4;6.3.4 Tests for Other Mechanical Material Properties;256
9.4;6.4 Electrical Test Structures;257
9.5;6.5 Thin-Film Material Properties;264
9.5.1;6.5.1 Thermal SiO2;264
9.5.2;6.5.2 LPCVD Polysilicon;265
9.5.3;6.5.3 LPCVD Silicon Dioxide (SiO2);269
9.5.4;6.5.4 LPCVD Silicon Nitride (SiN);271
9.5.5;6.5.5 PECVD Silicon Dioxide (SiO2);273
9.5.6;6.5.6 PECVD Silicon Nitride (SiN);275
9.5.7;6.5.7 PECVD Polycrystalline Silicon;277
9.5.8;6.5.8 Evaporative Physical Vapor Deposition;277
9.5.9;6.5.9 Sputter Physical Vapor Deposition;280
9.5.9.1;6.5.9.1 Sputter-Deposited Silicon;280
9.5.10;6.5.10 Electrochemical Deposition;281
9.6;6.6 Summary;283
9.7;References;283
10;Chapter 7: Microsystems Process Integration, Testing, and Packaging;288
10.1;7.1 Introduction;288
10.2;7.2 What Is Process Integration?;289
10.3;7.3 How Is Process Integration Performed?;291
10.4;7.4 What Is an Integrated MEMS Process Sequence?;296
10.5;7.5 Examples of MEMS Microsystems Process Technologies;296
10.5.1;7.5.1 PolyMUMPS Process Technology;297
10.5.1.1;7.5.1.1 Some Important Elements About PolyMUMPS;302
10.5.2;7.5.2 Digital Light Processor (DLP) Technology;304
10.5.2.1;7.5.2.1 Some Key Elements About the DLP Process Technology;307
10.6;7.6 Process Integration and Manufacturing Variations;308
10.6.1;7.6.1 Causes of Device Parameter Variations in Process Sequences;308
10.6.2;7.6.2 An Example of Parameter Variations for a Process Technology: The PolyMUMPS Process;311
10.7;7.7 Microsystems Design Rules;314
10.7.1;7.7.1 MEMS Microsystems Design Rules;314
10.7.2;7.7.2 Design Rule Checking;316
10.8;7.8 MEMS Microsystems Testing;317
10.8.1;7.8.1 Example of MEMS Microsystems Testing;318
10.8.2;7.8.2 MEMS Microsystems Device Trimming;319
10.8.3;7.8.3 MEMS Microsystems Calibration;320
10.9;7.9 MEMS Microsystems Packaging;320
10.10;7.10 Summary;323
10.11;References;323
11;Chapter 8: Device Parameter Variations in Microsystems Manufacturing;325
11.1;8.1 Introduction;325
11.2;8.2 Manufacturing Variations;326
11.3;8.3 Measurement of Manufacturing Variations;327
11.4;8.4 Bias and Random Variations;328
11.5;8.5 Resolution, Precision, and Accuracy;331
11.6;8.6 Comparison of the Dimensional Parameter Variations in Manufacturing Technologies;333
11.7;8.7 The Nature of Random Parameter Variations;337
11.8;8.8 Discrete Probability Distributions;354
11.9;8.9 Some Examples of Statistical Analysis of Variations;357
11.9.1;8.9.1 Confidence Interval for Manufacturing Large Samples (N > 30);357
11.9.2;8.9.2 Confidence Interval for Small Samples (N < 30);359
11.9.3;8.9.3 Hypothesis Testing for Small Sample Sizes (N < 30);359
11.9.4;8.9.4 Hypothesis Testing of Goodness of Fit;363
11.9.5;8.9.5 Sample Size Required to Estimate Population Mean;365
11.9.6;8.9.6 Example of Use of the Hypergeometric Distribution;366
11.9.7;8.9.7 Example of Poisson Distribution;366
11.10;8.10 Impact of Physics and Random Parameter Variations;367
11.11;8.11 Combination of Both Bias and Random Manufacturing Parameter Variations;371
11.12;8.12 Device Output Behavior Variation Due to Parameter Variations;373
11.13;8.13 Example of Device Output Behavior Variation Analysis;375
11.14;8.14 Simplified Variation Analysis;382
11.15;8.15 Important Generalizations;384
11.16;8.16 Review of Methods for Variation Analysis;387
11.16.1;8.16.1 Worst-Case Variation Analysis;389
11.16.2;8.16.2 Non-worst-Case Variation Analysis;393
11.16.2.1;8.16.2.1 Non-sampling, Non-worst-Case Variation Analysis;393
11.16.2.2;8.16.2.2 Monte Carlo Variation Analysis;394
11.17;8.17 Summary;398
11.18;References;399
12;Chapter 9: Yield Analysis and Quality Assurance and Control Methods Used in Microsystems Manufacturing;400
12.1;9.1 Introduction;400
12.2;9.2 Importance of Manufacturing Yield;401
12.3;9.3 Definitions of Microsystems Manufacturing Yield;402
12.4;9.4 Microsystems Manufacturing Yield Monitoring and Analysis;404
12.4.1;9.4.1 Functional Yield;405
12.4.1.1;9.4.1.1 Functional Yield Models Based on Point Defects;406
12.4.1.2;9.4.1.2 Functional Yield Measurement Tools;410
12.4.2;9.4.2 Parametric Yield;411
12.4.2.1;9.4.2.1 Parametric Yield Model;411
12.4.2.2;9.4.2.2 An Example of a Parametric Yield Model;419
12.5;9.5 Yield Estimations Using Sampling Methods;421
12.5.1;9.5.1 Yield Estimation Using Regionalization;422
12.5.2;9.5.2 Yield Estimation Using Simplicial Approximation;425
12.5.3;9.5.3 Monte Carlo Yield Estimation;428
12.5.3.1;9.5.3.1 Confidence Intervals for Monte Carlo Yield Analysis;429
12.6;9.6 Statistical Process Control (SPC);431
12.6.1;9.6.1 Control Charts for Variables;435
12.6.2;9.6.2 Control Charts for Attributes;440
12.6.3;9.6.3 Identification of Non-random Patterns in Control Charts;445
12.6.4;9.6.4 Process Capability;446
12.6.5;9.6.5 Rational Subgroups;450
12.6.5.1;9.6.5.1 Sampling Methods for Rational Subgroups;454
12.7;9.7 Summary;456
12.8;References;456
13;Chapter 10: Managing Parameter Variations in Microsystems Device Design;458
13.1;10.1 Introduction;458
13.2;10.2 Relationships Between Process Sequence and Parameter Variations;460
13.3;10.3 Overview of MEMS Device Design and Modeling;462
13.4;10.4 Example of the Design Levels for a MEMS Device;465
13.5;10.5 MEMS Design for Manufacturability;469
13.5.1;10.5.1 MEMS Device Design for Manufacturability;470
13.5.2;10.5.2 MEMS Process Sequence Design for Manufacturability;471
13.5.3;10.5.3 MEMS Microsystems Partitioning;473
13.6;10.6 Overview of MEMS Development;474
13.7;10.7 MEMS Design for Manufacturability Recommendations;477
13.8;10.8 Managing Device Parameter Variations in MEMS Design;478
13.8.1;10.8.1 Design Centering;480
13.8.2;10.8.2 Parameter Variation Reduction;484
13.8.3;10.8.3 Device Size Scaling;486
13.8.4;10.8.4 Acceptance Range Increase;488
13.8.5;10.8.5 Best Practices in Layout Design;489
13.8.6;10.8.6 Further Comments About MEMS Design Methods;496
13.9;10.9 MEMS Design in Multidimensional Spaces;497
13.10;10.10 MEMS Design Methods Using Monte Carlo Techniques;502
13.10.1;10.10.1 Design Centering Using Monte Carlo;505
13.11;10.11 Sensitivity Analysis;509
13.11.1;10.11.1 Generalized Sensitivity Analysis Methods;512
13.11.2;10.11.2 Optimizing Manufacturing Cost Function;516
13.12;10.12 Summary;517
13.13;References;517
14;Index;519