Page 8 - Sami Franssila Introduction to Microfabrication

Contents vii

7.8 Thin films over topography: step coverage 86
7.9 Simulation of deposition 88
7.10 Exercises 90
References and related readings 90

PART III: BASIC PROCESSES 91

8 Pattern Generation 93
8.1 Beam writing strategies 93
8.2 Electron beam physics 94
8.3 Photomask fabrication 94
8.4 Photomasks as tools 95
8.5 Photomask inspection, defects and repair 96
8.6 Exercises 97
References and related readings 97

9 Optical Lithography 99
9.1 Lithography tools (alignment and exposure) 99
9.2 Resolution 101
9.3 Basic pattern shapes 102
9.4 Alignment and overlay 103
9.5 Exercises 104
References and related readings 104

10 Lithographic Patterns 107
10.1 Resist application 107
10.2 Resist chemistry 108
10.3 Thin film optics in resists 110
10.4 Extending optical lithography 112
10.5 Lithography simulation 113
10.6 Lithography practice 114
10.7 Photoresist stripping/ashing 116
10.8 Exercises 117
References and related readings 117

11 Etching 119
11.1 Wet etching 120
11.2 Electrochemical etching 123
11.3 Anisotropic wet etching 125
11.4 Plasma etching 125
11.5 Characterization of etch processes 128
11.6 Etch processes for common materials 128
11.7 Etch time and spacers 129
11.8 Comparison of wet etching, anisotropic wet etching and plasma etching 130
11.9 Exercises 130
References and related readings 131

12 Wafer Cleaning and Surface Preparation 133
12.1 Contamination forms 133
12.2 Wet cleaning 135