Functionalization of Semiconductor Surfaces

Preface xv

Contributors xix

1. Introduction 1
Franklin (Feng) Tao, Yuan Zhu, and Steven L. Bernasek

1.1 Motivation for a Book on Functionalization of Semiconductor Surfaces 1

1.2 Surface Science as the Foundation of the Functionalization of Semiconductor Surfaces 2

1.2.1 Brief Description of the Development of Surface Science 2

1.2.2 Importance of Surface Science 3

1.2.3 Chemistry at the Interface of Two Phases 4

1.2.4 Surface Science at the Nanoscale 5

1.2.5 Surface Chemistry in the Functionalization of Semiconductor Surfaces 7

1.3 Organization of this Book 7

References 9

2. Surface Analytical Techniques 11
Ying Wei Cai and Steven L. Bernasek

2.1 Introduction 11

2.2 Surface Structure 12

2.2.1 Low-Energy Electron Diffraction 13

2.2.2 Ion Scattering Methods 14

2.2.3 Scanning Tunneling Microscopy and Atomic Force Microscopy 15

2.3 Surface Composition, Electronic Structure, and Vibrational Properties 16

2.3.1 Auger Electron Spectroscopy 16

2.3.2 Photoelectron Spectroscopy 17

2.3.3 Inverse Photoemission Spectroscopy 18

2.3.4 Vibrational Spectroscopy 18

2.3.4.1 Infrared Spectroscopy 19

2.3.4.2 High-Resolution Electron Energy Loss Spectroscopy 19

2.3.5 Synchrotron-Based Methods 20

2.3.5.1 Near-Edge X-Ray Absorption Fine Structure Spectroscopy 20

2.3.5.2 Energy Scanned PES 21

2.3.5.3 Glancing Incidence X-Ray Diffraction 21

2.4 Kinetic and Energetic Probes 21

2.4.1 Thermal Programmed Desorption 22

2.4.2 Molecular Beam Sources 22

2.5 Conclusions 23

References 23

3. Structures of Semiconductor Surfaces and Origins of Surface Reactivity with Organic Molecules 27
Yongquan Qu and Keli Han

3.1 Introduction 27

3.2 Geometry, Electronic Structure, and Reactivity of Clean Semiconductor Surfaces 28

3.2.1 Si(100)-(2×1), Ge(100)-(2×1), and Diamond(100)-(2×1) Surfaces 29

3.2.2 Si(111)-(7×7) Surface 33

3.3 Geometry and Electronic Structure of H-Terminated Semiconductor Surfaces 34

3.3.1 Preparation and Structure of H-Terminated Semiconductor Surfaces Under UHV 34

3.3.2 Preparation and Structure of H-Terminated Semiconductor Surfaces in Solution 35

3.3.3 Preparation and Structure of H-Terminated Semiconductor Surfaces Through Hydrogen Plasma Treatment 36

3.3.4 Reactivity of H-Terminated Semiconductor Surface Prepared Under UHV 36

3.3.5 Preparation and Structure of Partially H-Terminated Semiconductor Surfaces 36

3.3.6 Reactivity of Partially H-Terminated Semiconductor Surfaces Under Vacuum 38

3.4 Geometry and Electronic Structure of Halogen-Terminated Semiconductor Surfaces 39

3.4.1 Preparation of Halogen-Terminated Semiconductor Surfaces Under UHV 40

3.4.2 Preparation of Halogen-Terminated Semiconductor Surfaces from H-Terminated Semiconductor Surfaces 41

3.5 Reactivity of Hydrogen- or Halogen-Terminated Semiconductor Surfaces in Solution 41

3.5.1 Reactivity of Si and Ge Surfaces in Solution 41

3.5.2 Reactivity of Diamond Surfaces in Solution 43

3.6 Summary 45

Acknowledgments 46

References 46

4. Pericyclic Reactions of Organic Molecules at Semiconductor Surfaces 51
Keith T. Wong and Stacey F. Bent

4.1 Introduction 51

4.2 [2+2] Cycloaddition of Alkenes and Alkynes 53

4.2.1 Ethylene 53

4.2.2 Acetylene 57

4.2.3 Cis- and Trans-2-Butene 58

4.2.4 Cyclopentene 59

4.2.5 [2+2]-Like Cycloaddition on Si(111)-(7×7) 61

4.3 [4+2] Cycloaddition of Dienes 62

4.3.1 1,3-Butadiene and 2,3-Dimethyl-1,3-Butadiene 63

4.3.2 1,3-Cyclohexadiene 66

4.3.3 Cyclopentadiene 67

4.3.4 [4+2]-Like Cycloaddition on Si(111)-(7×7) 69

4.4 Cycloaddition of Unsaturated Organic Molecules Containing One or More Heteroatom 71

4.4.1 C=O-Containing Molecules 71

4.4.2 Nitriles 78

4.4.3 Isocyanates and Isothiocyanates 80

4.5 Summary 81

Acknowledgment 83

References 83

5. Chemical Binding of Five-Membered and Six-Membered Aromatic Molecules 89
Franklin (Feng) Tao and Steven L. Bernasek

5.1 Introduction 89

5.2 Five-Membered Aromatic Molecules Containing One Heteroatom 89

5.2.1 Thiophene, Furan, and Pyrrole on Si(111)-(7×7) 90

5.2.2 Thiophene, Furan, and Pyrrole on Si(100) and Ge(100) 92

5.3 Five-Membered Aromatic Molecules Containing Two Different Heteroatoms 95

5.4 Benzene 98

5.4.1 Different Binding Configurations on (100) Face of Silicon and Germanium 98

5.4.2 Di-Sigma Binding on Si(111)-(7×7) 99

5.5 Six-Membered Heteroatom Aromatic Molecules 100

5.6 Six-Membered Aromatic Molecules Containing Two Heteroatoms 101

5.7 Electronic and Structural Factors of the Semiconductor Surfaces for the Selection of Reaction Channels of Five-Membered and Six-Membered Aromatic Rings 102

References 103

6. Influence of Functional Groups in Substituted Aromatic Molecules on the Selection of ReactionChannel in Semiconductor Surface Functionalization 105
Andrew V. Teplyakov

6.1 Introduction 105

6.1.1 Scope of this Chapter 105

6.1.2 Structure of Most Common Elemental Semiconductor Surfaces: Comparison of Silicon with Germanium and Carbon 107

6.1.3 Brief Overview of the Types of Chemical Reactions Relevant for Aromatic Surface Modification of Clean Semiconductor Surfaces 111

6.2 Multifunctional Aromatic Reactions on Clean Silicon Surfaces 113

6.2.1 Homoaromatic Compounds Without Additional Functional Groups 113

6.2.2 Functionalized Aromatics 116

6.2.2.1 Dissociative Addition 116

6.2.2.2 Cycloaddition 120

6.2.3 Heteroaromatics: Aromaticity as a Driving Force in Surface Processes 130

6.2.4 Chemistry of Aromatic Compounds on Partially Hydrogen-Covered Silicon Surfaces 137

6.2.5 Delivery of Aromatic Groups onto a Fully Hydrogen Covered Silicon Surface 147

6.2.5.1 Hydrosilylation 147

6.2.5.2 Cyclocondensation 148

6.2.6 Delivery of Aromatic Compounds onto Protected Silicon Substrates 150

6.3 Summary 151

Acknowledgments 152

References 152

7. Covalent Binding of Polycyclic Aromatic Hydrocarbon Systems 163
Kian Soon Yong and Guo-Qin Xu

7.1 Introduction 163

7.2 PAHs on Si(100)-(2×1) 165

7.2.1 Naphthalene and Anthracene on Si(100)-(2×1) 165

7.2.2 Tetracene on Si(100)-(2×1) 167

7.2.3 Pentacene on Si(100)-(2×1) 169

7.2.4 Perylene on Si(100)-(2×1) 172

7.2.5 Coronene on Si(100)-(2×1) 173

7.2.6 Dibenzo[a, j ]coronene on Si(100)-(2×1) 174

7.2.7 Acenaphthylene on Si(100)-(2×1) 175

7.3 PAHs on Si(111)-(7×7) 176

7.3.1 Naphthalene on Si(111)-(7×7) 176

7.3.2 Tetracene on Si(111)-(7×7) 179

7.3.3 Pentacene on Si(111)-(7×7) 184

7.4 Summary 189

References 190

8. Dative Bonding of Organic Molecules 193
Young Hwan Min, Hangil Lee, Do Hwan Kim, and Sehun Kim

8.1 Introduction 193

8.1.1 What is Dative Bonding? 193

8.1.2 Periodic Trends in Dative Bond Strength 194

8.1.3 Examples of Dative Bonding: Ammonia and Phosphine on Si(100) and Ge(100) 197

8.2 Dative Bonding of Lewis Bases (Nucleophilic) 198

8.2.1 Aliphatic Amines 198

8.2.1.1 Primary, Secondary, and Tertiary Amines on Si(100) and Ge(100) 198

8.2.1.2 Cyclic Aliphatic Amines on Si(100) and Ge(100) 202

8.2.1.3 Ethylenediamine on Ge(100) 204

8.2.2 Aromatic Amines 206

8.2.2.1 Aniline on Si(100) and Ge(100) 207

8.2.2.2 Five-Membered Heteroaromatic Amines: Pyrrole on Si(100) and Ge(100) 209

8.2.2.3 Six-Membered Heteroaromatic Amines 211

8.2.3 O-Containing Molecules 218

8.2.3.1 Alcohols on Si(100) and Ge(100) 218

8.2.3.2 Ketones on Si(100) and Ge(100) 219

8.2.3.3 Carboxyl Acids on Si(100) and Ge(100) 220

8.2.4 S-Containing Molecules 223

8.2.4.1 Thiophene on Si(100) and Ge(100) 223

8.3 Dative Bonding of Lewis Acids (Electrophilic) 225

8.4 Summary 226

References 229

9. Ab Initio Molecular Dynamics Studies of Conjugated Dienes on Semiconductor Surfaces 233
Mark E. Tuckerman and Yanli Zhang

9.1 Introduction 233

9.2 Computational Methods 234

9.2.1 Density Functional Theory 235

9.2.2 Ab Initio Molecular Dynamics 237

9.2.3 Plane Wave Bases and Surface Boundary Conditions 239

9.2.4 Electron Localization Methods 244

9.3 Reactions on the Si(100)-(2×1) Surface 247

9.3.1 Attachment of 1,3-Butadiene to the Si(100)-(2×1) Surface 249

9.3.2 Attachment of 1,3-Cyclohexadiene to the Si(100)-(2×1) Surface 257

9.4 Reactions on the SiC(100)-(3×2) Surface 263

9.5 Reactions on the SiC(100)-(2×2) Surface 266

9.6 Calculation of STM Images: Failure of Perturbative Techniques 270

References 273

10. Formation of Organic Nanostructures on Semiconductor Surfaces 277
Md. Zakir Hossain and Maki Kawai

10.1 Introduction 277

10.2 Experimental 278

10.3 Results and Discussion 279

10.3.1 Individual 1D Nanostructures on Si(100)–H: STM Study 279

10.3.1.1 Styrene and Its Derivatives on Si(100)-(2×1)–H 279

10.3.1.2 Long-Chain Alkenes on Si(100)-(2×1)–H 284

10.3.1.3 Cross-Row Nanostructure 285

10.3.1.4 Aldehyde and Ketone: Acetophenone –A Unique Example 287

10.3.2 Interconnected Junctions of 1D Nanostructures 292

10.3.2.1 Perpendicular Junction 292

10.3.2.2 One-Dimensional Heterojunction 295

10.3.3 UPS of 1D Nanostructures on the Surface 296

10.4 Conclusions 298

Acknowledgment 299

References 299

11. Formation of Organic Monolayers Through Wet Chemistry 301
Damien Aureau and Yves J. Chabal

11.1 Introduction, Motivation, and Scope of Chapter 301

11.1.1 Background 301

11.1.2 Formation of H-Terminated Silicon Surfaces 303

11.1.3 Stability of H-Terminated Silicon Surfaces 304

11.1.4 Approach 305

11.1.5 Outline 305

11.2 Techniques Characterizing Wet Chemically Functionalized Surfaces 307

11.2.1 X-Ray Photoelectron Spectroscopy 307

11.2.2 Infrared Absorption Spectroscopy 308

11.2.3 Secondary Ion Mass Spectrometry 310

11.2.4 Surface-Enhanced Raman Spectroscopy 311

11.2.5 Spectroscopic Ellipsometry 311

11.2.6 X-Ray Reflectivity 312

11.2.7 Contact Angle, Wettability 312

11.2.8 Photoluminescence 312

11.2.9 Electrical Measurements 313

11.2.10 Imaging Techniques 313

11.2.11 Electron and Atom Diffraction Methods 313

11.3 Hydrosilylation of H-Terminated Surfaces 314

11.3.1 Catalyst-Aided Reactions 315

11.3.2 Photochemically Induced Reactions 318

11.3.3 Thermally Activated Reactions 320

11.4 Electrochemistry of H-Terminated Surfaces 322

11.4.1 Cathodic Grafting 322

11.4.2 Anodic Grafting 323

11.5 Use of Halogen-Terminated Surfaces 324

11.6 Alcohol Reaction with H-Terminated Si Surfaces 327

11.7 Outlook 331

Acknowledgments 331

References 332

12. Chemical Stability of Organic Monolayers Formed in Solution 339
Leslie E. O’Leary, Erik Johansson, and Nathan S. Lewis

12.1 Reactivity of H-Terminated Silicon Surfaces 339

12.1.1 Background 339

12.1.1.1 Synthesis of H-Terminated Si Surfaces 339

12.1.2 Reactivity of H-Si 342

12.1.2.1 Aqueous Acidic Media 342

12.1.2.2 Aqueous Basic Media 343

12.1.2.3 Oxygen-Containing Environments 344

12.1.2.4 Alcohols 344

12.1.2.5 Metals 345

12.2 Reactivity of Halogen-Terminated Silicon Surfaces 347

12.2.1 Background 347

12.2.1.1 Synthesis of Cl-Terminated Surfaces 348

12.2.1.2 Synthesis of Br-Terminated Surfaces 350

12.2.1.3 Synthesis of I-Terminated Surfaces 350

12.2.2 Reactivity of Halogenated Silicon Surfaces 351

12.2.2.1 Halogen Etching 351

12.2.2.2 Aqueous Media 352

12.2.2.3 Oxygen-Containing Environments 353

12.2.2.4 Alcohols 355

12.2.2.5 Other Solvents 356

12.2.2.6 Metals 359

12.3 Carbon-Terminated Silicon Surfaces 360

12.3.1 Introduction 360

12.3.2 Structural and Electronic Characterization of Carbon-Terminated Silicon 361

12.3.2.1 Structural Characterization of CH₃-Si(111) 362

12.3.2.2 Structural Characterization of Other Si-C Functionalized Surfaces 362

12.3.2.3 Electronic Characterization of Alkylated Silicon 364

12.3.3 Reactivity of C-Terminated Silicon Surfaces 366

12.3.3.1 Thermal Stability of Alkylated Silicon 367

12.3.3.2 Stability in Aqueous Conditions 367

12.3.3.3 Stability of Si-C Terminated Surfaces in Air 371

12.3.3.4 Stability of Si-C Terminated Surfaces in Alcohols 372

12.3.3.5 Stability in Other Common Solvents 372

12.3.3.6 Silicon–Organic Monolayer–Metal Systems 374

12.4 Applications and Strategies for Functionalized Silicon Surfaces 376

12.4.1 Tethered Redox Centers 378

12.4.2 Conductive Polymer Coatings 379

12.4.3 Metal Films 382

12.4.3.1 Stability Enhancement 382

12.4.3.2 Deposition on Organic Monolayers 382

12.4.4 Semiconducting and Nonmetallic Coatings 389

12.4.4.1 Stability Enhancement 389

12.4.4.2 Deposition on Si by ALD 389

12.5 Conclusions 391

References 392

13. Immobilization of Biomolecules at Semiconductor Interfaces 401
Robert J. Hamers

13.1 Introduction 401

13.2 Molecular and Biomolecular Interfaces to Semiconductors 402

13.2.1 Functionalization Strategies 402

13.2.2 Silane Derivatives 403

13.2.3 Phosphonic Acids 406

13.2.4 Alkene Grafting 406

13.3 DNA-Modified Semiconductor Surfaces 407

13.3.1 DNA-Modified Silicon 407

13.3.2 DNA-Modified Diamond 411

13.3.3 DNA on Metal Oxides 412

13.4 Proteins at Surfaces 415

13.4.1 Protein-Resistant Surfaces 415

13.4.2 Protein-Selective Surfaces 417

13.5 Covalent Biomolecular Interfaces for Direct Electrical Biosensing 418

13.5.1 Detection Methods on Planar Surfaces 418

13.5.2 Sensitivity Considerations 420

13.6 Nanowire Sensors 422

13.7 Summary 422

Acknowledgments 423

References 423

14. Perspective and Challenge 429
Franklin (Feng) Tao and Steven L. Bernasek

Index 431

FRANKLIN (FENG) TAO, PHD, is Assistant Professor of Chemistry at the University of Notre Dame. His research group is actively involved in investigations of surface science, heterogeneous catalysis for efficient energy conversion, nanomaterials, and in situ studies of catalysts. Dr. Tao is the author of about 70 research articles and the recipient of the International Union of Pure and Applied Chemistry Prize for Young Chemists.

STEVEN L. BERNASEK, PHD, is Professor of Chemistry at Princeton University. His research focuses on chirality in self-assembled monolayers, surface functionalization and modification, organometallic surface chemistry, and dynamics of gas-surface interactions. Dr. Bernasek is the author of more than 200 research articles. He is also the recipient of several awards, including the ACS Arthur W. Adamson Award for Distinguished Service in the Advancement of Surface Chemistry.