Chemical-mechanical polishing of low dielectric constant polymers and organosilicate glasses : fundamental mechanisms and application to IC interconnect technology / by Christopher L. Borst, William N. Gill, Ronald J. Gutmann.

Format:

Book

Author/Creator:

Borst, Christopher L. (Christopher Lyle)

Contributor:

Gill, William N.

Gutmann, Ronald J.

Language:

English

Subjects (All):

Interconnects (Integrated circuit technology).

Semiconductors--Polishing.

Semiconductors.

Grinding and polishing.

Physical Description:

xiv, 229 pages : illustrations ; 25 cm

Place of Publication:

Boston : Kluwer Academic Publishers, [2002]

Contents:

Chapter 1 Overview of IC Interconnects 1

1.1 Silicon IC Beol Technology Trends 2

1.2 SIA Roadmap Interconnect Projections 6

1.3 Low-[kappa] Requirements and Materials 7

1.3.1 Fluorinated Glasses 8

1.3.2 Spin-On Glasses and Silsesquioxanes 8

1.3.3 Organosilicate Glasses 9

1.3.4 Polymers 9

1.3.5 Fluorinated Polymers 11

1.3.6 Porous Media 11

1.4 Need for Low-[kappa] CMP Process Understanding 12

Chapter 2 Low-[kappa] Interlevel Dielectrics 17

2.1 Fluorinated Glasses 19

2.2 Silsesquioxanes 21

2.3 Organosilicate Glasses 24

2.4 Polymers 27

2.5 Fluorinated Hydrocarbons 34

2.6 Nanoporous Silica Films 35

2.7 Other Porous Materials 38

Chapter 3 Chemical-Mechanical Planarization (CMP) 45

3.1 CMP Process Description 47

3.2 CMP Processes with Copper Metallization 50

3.2.1 Oxide CMP 50

3.2.2 Copper CMP 50

3.2.3 Damascene Patterning 52

3.2.4 CMP Targeted Results and Challenges 55

3.3 CMP of Low-[kappa] Materials 55

3.4 CMP Process Models 62

3.4.1 Contact Mechanics-Based Models 63

3.4.2 Fluid Mechanics-Based Models 64

3.5 Langmuir-Hinshelwood Surface Kinetics in CMP Modeling 66

Chapter 4 CMP of BCB and SiLK Polymers 71

4.1 Removal Rate in Copper Slurries 71

4.2 Surface Roughness 74

4.3 Surface and Bulk Film Chemistry 78

4.3.1 Angle-Resolved Surface Results 78

4.3.2 Depth Profiling Results 84

4.4 Effect of Cure Conditions on BCB and Silk Removal 85

4.4.1 Variation in Cure Conditions 86

4.4.2 Effect of Cure Conditions on Removal Rate 86

4.5 Effect of CMP and BCB and Silk Film Hardness 88

4.6 Comparison of BCB and Silk CMP with Other Polymer CMP 91

Chapter 5 CMP of Organosilicate Glasses 97

5.1 Effect of Film Carbon Content 97

5.1.1 Removal Rate in Oxide Slurries 98

5.1.2 Removal Rate in Copper Slurries 101

5.2 Surface Roughness 103

5.3 Surface and Bulk Film Chemistry 106

5.3.1 XPS Surface Results 107

5.3.2 FTIR Bulk Profiling Results 109

5.4 Copper Damascene Patterning with OSG Dielectrics 110

5.4.1 Hardmasks or Dielectric Cap Layers 111

5.4.2 Low-[kappa] Etching 112

5.4.3 CMP Integration 113

Chapter 6 Low-[kappa] CMP Model Based on Surface Kinetics 119

6.1 Isolation of the Chemical Effects in Silk CMP 120

6.2 CMP with Simplified "Model" Silk Slurries 122

6.2.1 Removal Rate Dependence on Slurry Reactant Concentration 124

6.2.2 KH Phthalate Slurry for Copper CMP Applications 127

6.2.3 SiLK Removal Rate Dependence on Velocity 128

6.3 Phenomenological Model for CMP Removal 129

6.3.1 Applicability to the CMP of BCB and SiLK 131

6.3.2 Applicability to the CMP of Organosilicate Glasses 133

6.4 Five Step Removal Model Using Modified Langmuir-Hinshel Wood Kinetics for Silk CMP 134

6.4.1 Five Step Surface Mechanism 135

6.4.2 Implementation into 3-D Fluid Mechanics and Mass Transport Models 139

6.4.3 Results 141

6.5 Two Step Removal Model Using Heterogeneous Catalysis for Silk CMP 152

6.5.1 Two Step Surface Mechanism 152

6.5.2 Results 154

6.6 Extendibility of Model to Describe the CMP of Other Materials 155

6.6.1 Copper 156

6.6.2 Dielectrics 156

Chapter 7 Copper CMP Model Based Upon Fluid Mechanics And Surface Kinetics 161

7.1 Flow Model 163

7.2 Copper Removal Model 164

7.2.1 Mass Transport of Oxidizer to the Wafer Surface 165

7.2.2 Kinetic Surface Steps 166

7.2.3 Copper Removal Rate and Effectiveness Factor 168

7.2.4 Kinetic Rate Parameters 170

7.2.5 Solution Procedure 171

7.3 Model Results 172

7.4 Copper CMP Experiments with Potassium Dichromate Based Slurry 176

Chapter 8 Future Directions in IC Interconnects and Related Low-[kappa] ILD Planarization Issues 181

8.1 Planarization of Interconnects with Ultra Low-[kappa] ILDs 182

8.1.1 Alternatives to Conventional CMP 182

8.1.2 Non-CMP Approaches to Planarization 183

8.2 Alternatives for the Post-Copper/Ultra Low-[kappa] Interconnect ERA 185

8.2.1 Alternative Materials 185

8.2.2 Alternative Distribution for Signals and Clocks 186

8.2.3 Non-electrical Distribution of Signals and Clocks 188

8.2.4 Non-Planar Integrated Assemblies

Three Dimensional (3D) Integration 189

8.3 3D Wafer-Scale Integration Using Dielectric Bonding Glues and Inter-Wafer Interconnection with Copper Damascene Patterning 193

8.3.1 Wafer Bonding 194

8.3.2 Inter-wafer Interconnect 197

8.3.3 Comparison with Other Wafer-Scale 3D Integration Technologies 199

Appendix A Experimental Procedures and Techniques 203

Appendix B XPS Depth-Profile Data 221

Appendix C CMP Data for Anomalous Silk Removal Behavior 225.

Notes:

Includes bibliographical references and index.

ISBN:

1402071930

OCLC:

50243109