Page 10 - Sami Franssila Introduction to Microfabrication

Contents ix

17.4 Bonding mechanics 178
17.5 Bonding of structured wafers 179
17.6 Bonding for SOI wafer fabrication 180
17.7 Layer transfer 180
17.8 Exercises 181
References and related readings 181

18 Moulding and Stamping 183
18.1 Moulding 183
18.2 2D surface stamping 186
18.3 3D-volume stamping 187
18.4 Comparison with lithography 189
18.5 Exercises 189
References 189

PART IV: STRUCTURES 191

19 Self-aligned Structures 193
19.1 Self-aligned MOS gate 193
19.2 Self-aligned twin well 194
19.3 Spacers and self-aligned silicide (salicide) 194
19.4 Self-aligned junctions 196
19.5 Exercises 197
References and related readings 197

20 Plasma-etched Structures 199
20.1 Multi-step etching 199
20.2 Multi-layer etching 200
20.3 Resist effects on etching 201
20.4 Non-masked etching 201
20.5 Pattern size and pattern density effects 202
20.6 Etch residues and damage 203
20.7 Exercises 203
References and related readings 204

21 Wet-etched Silicon Structures 205
21.1 Basic structures on <100> silicon 205
21.2 Etchants 205
21.3 Etch masks and protective coatings 206
21.4 Etch rate and etch stop 207
21.5 Diaphragm fabrication 208
21.6 Complex shapes by <100> etching 209
21.7 Front side bulk micromachining 211
21.8 Corner compensation 212
21.9 <110> Etching 212
21.10 <111> silicon etching 213
21.11 Comparison of <100>, <110> and <111> etching 215
21.12 Exercises 215
References and related readings 216