Page 11 - Sami Franssila Introduction to Microfabrication

x Contents

22 Sacrificial and Released Structures 217
22.1 Structural and sacrificial layers 217
22.2 Single structural layer 218
22.3 Stiction 219
22.4 Two structural–layer processes 220
22.5 Rotating structures 222
22.6 Hinged structures 222
22.7 Sacrificial structures using porous silicon 223
22.8 Exercises 223
References and related readings 224

23 Structures by Deposition 227
23.1 Plated structures 227
23.2 Lift-off metallization 228
23.3 Special deposition applications 229
23.4 Localized deposition 230
23.5 Sealing of cavities 232
23.6 Exercises 233
References and related readings 233

PART V: INTEGRATION 235

24 Process Integration 237
24.1 Process integration aspects of a solar-cell process 237
24.2 Wafer selection 238
24.3 Patterns 241
24.4 Design rules 242
24.5 Contamination budget 247
24.6 Thermal processes 248
24.7 Thermal budget 249
24.8 Metallization 249
24.9 Reliability 250
24.10 Exercises 252
References and related readings 253

25 CMOS Transistor Fabrication 255
25.1 5 µm polysilicon gate CMOS process 255
25.2 MOS transistor scaling 258
25.3 Advanced CMOS issues 260
25.4 Gate module 262
25.5 Contact to silicon 265
25.6 Exercises 266
References and related readings 267

26 Bipolar Technology 269
26.1 Fabrication process of SBC bipolar transistor 269
26.2 Advanced bipolar structures 272
26.3 BiCMOS technology 275
26.4 Exercises 275
References and related readings 276