Up-to-date practitioner’s guide on LED packaging technologies, with application examples from relevant industries, historical insight, and outlook
LED Packaging Technologies provides expert insight into current and future trends in LED packaging technologies, discussing the fundamentals of LED packaging technologies, from electrical contact design, thermal management and optical emission, and extraction, to manufacturing technologies, including the JEDEC testing standards, followed by accounts on the main applications of these LED packages in the automotive, consumer electronics, and lighting industries.
LED Packaging Technologies includes information on:
- History of primitive lighting in human civilization to the invention of modern LEDs based lighting, and historic evolution of LED packaging technology
- Basic light emission and extraction technology in LED packages, covering package design impacting light emission and extraction
- Medical industry applications of LEDs, especially in healthcare treatments, such as in skin rejuvenation and wound healing and closures
- Quantum confinement phenomena and size-dependent optical properties of quantum dots, and the advancement of future quantum dot LEDs
Covering the fundamentals, design, and manufacturing of LED packaging technology and assisting in removing some of the barriers in the development of LED packaging and new applications, LED Packaging Technologies is an essential source of information for engineers in the LED and lighting industries, as well as researchers in academia.
Table of Contents
About the Authors vii
Preface ix
Acknowledgments xiii
1 A Brief History of Artificial Light and LED Packaging 1
1.1 Evolution in Artificial Light 1
1.2 Impact of Light-Emitting Diode on the World 4
1.3 LED Industrial Chain 6
1.4 Evolution in LED Packaging Technology 8
1.4.1 Low-Power Package Evolution 12
1.4.2 Mid-Power LED Packages 14
1.4.3 LED High-Power and Ultra-High-Power Packages 15
1.5 Summary 17
References 18
2 Fundamentals of LED Packaging Technology 19
2.1 Effective Light Extraction 19
2.1.1 Theory of Light Conversion in LED 21
2.1.2 Light Extraction Based on Chip Technology 23
2.1.2.1 Chip Surface Roughing 25
2.1.2.2 Buried Micro-Reflectors Chip 26
2.1.2.3 Chip Geometrical Shaping and Type 26
2.1.3 Light Extraction Based on High Reflective Packaging Material 28
2.1.3.1 Leadframe Plating Surface Influence 28
2.1.3.2 Housing Material Reflectivity 29
2.1.3.3 Encapsulation Material Light Extraction Efficacy 29
2.1.4 Optical Interface Enhancing Light Extraction 31
2.2 Package Design and Encapsulation Technology 32
2.2.1 Package Design 32
2.2.1.1 Design for Cost 33
2.2.1.2 Design for Reliability 34
2.2.1.3 Design for Manufacturing 34
2.2.1.4 Design for Testing 34
2.2.1.5 Design for Environment 36
2.2.1.6 Design for Assembly at Second Level PCB Board 36
2.2.1.7 Design for Effective Light Extraction 37
2.2.2 Encapsulation of LED 37
2.2.2.1 Epoxy, Silicone, and Hybrid Compound Encapsulation 37
2.2.2.2 Hermetic Sealed Package - Metal Can 40
2.2.2.3 Epoxy Cap Encapsulation 41
2.2.2.4 Glass Cap on Ceramic or Aluminum Encapsulation 41
2.3 LED Thermal Management 42
2.3.1 Fundamental of the LED Thermal Behaviors 42
2.3.2 Thermal Design in LED Package 46
2.3.3 Impact of Thermal Behavior of an LED on Its Performance 48
2.4 Electrical Contact Design 49
2.5 LED Light Conversion Principle 50
2.6 Summary 50
References 51
3 LED Packaging Manufacturing Technology 53
3.1 LED Packaging Process Flow 53
3.1.1 Die-Attach Process 53
3.1.1.1 Die-Attach and Glue Curing Process 55
3.1.2 Wire Bonding Process 56
3.1.3 Surveillance Checking Using Statistical Process Control 58
3.1.4 Encapsulation Process and Post-Mold Curing Process 60
3.1.5 Singulation Process 62
3.1.6 Final Test and Auto Vision System Process 62
3.1.7 Packing Process 63
3.2 Common Defects in LED Packaging Industry 65
3.2.1 Die-crack: Impact on the Electrical and Optical Properties of LED 65
3.2.2 Lifted Die or Glue: Impact on LED Thermal Behavior and LED Performance 67
3.2.3 Wire Interconnect Defects: Impact on LED Electro-optical Quality 69
3.3 Summary 70
References 70
4 LED Automotive Lighting Application Technology 71
4.1 Basic Science of Light for Automotive - The Photometric 72
4.1.1 Light Intensity 72
4.1.2 Luminous Flux 73
4.1.3 Illuminance 74
4.1.4 Luminance 74
4.1.5 Luminous Efficacy 74
4.2 Lighting - Light Projection “To See” 74
4.2.1 Headlamp 75
4.2.2 Adaptive Front-Lighting System - Headlamp 77
4.2.3 Optical Concept Automotive Front Lighting - Headlamp 80
4.2.4 Future of LED Headlamp Technology 81
4.2.5 LED Headlamp Thermal Management 82
4.3 Signaling - Lights That Are “To Be Seen” 83
4.3.1 AFL - Day Running Light 84
4.3.2 ARL - Signaling Lights 85
4.3.3 Optic Concepts of Signaling Light “To Be Seen” 86
4.3.3.1 Reflective and Refractive Optics 86
4.3.3.2 Light Guide Optics 87
4.4 Interior Lighting 92
4.5 Summary 93
References 93
5 LED Application For Consumer Industry 95
5.1 Consumer Indoor Lighting 95
5.2 Health Care and Medical Treatments 96
5.3 Safety and Security 98
5.3.1 Led in Iris Recognition System 98
5.3.2 LED in Food Processing 100
5.3.3 Treatment in Solid and Liquid Foods 101
5.3.4 Water Treatment 102 References 102
6 LED Application for General Lighting 105
6.1 RETROFIT Lighting 105
6.1.1 RETROFIT Lamp 107
6.1.2 Hospitality Lighting - Architecture Lighting 111
6.2 LEDfit Lighting 112
6.2.1 Residential Lighting - Living Room Down Lighting 112
6.2.2 LED Street Lighting 113
6.2.3 Exterior Architectural Lighting 117
6.2.4 Horticulture Lighting Application 118
6.2.4.1 Photosynthesis 119
6.2.5 Photomorphogenesis 120
6.2.5.1 Impact of LED Light on Horticulture Industry 121
6.3 Summary 122
References 123
7 Quantum LEDs 125
7.1 Quantum LED as the Alternative to Organic LED 125
7.2 Fundamentals of Quantum Dot 125
7.3 Quantum Dots in LED 129
7.4 Quantum LED Structures 130
7.5 QD-LED Fabrication 132
References 134
8 Ultraviolet LED Packaging and Application 137
8.1 UV LED Application 137
8.2 UV-A and B LED Packaging Technology 140
8.3 UV-C Packaging Technology 142
8.4 Future Application of UV-LED and Packaging Design Evolution 143
8.4.1 Novel Liquid Packaging Structure 143
8.5 Impact of UV-LED to UV Light Source Business 144
8.6 Summary 144
References 145
9 Lifecycle Analysis and Circular Economy of LEDs 147
9.1 Introduction 147
9.2 LCA of LEDs 148
9.2.1 Materials Footprint 149
9.2.2 Embodied Energy and Carbon Footprint 151
9.3 Circular Economy of LEDs 152
9.3.1 Lower Material Quantities by Design and Enhanced Material Properties 153
9.3.2 Materials with Multifunctionalities 154
9.3.3 Materials of Higher Circularity 155
9.3.4 Materials with Enhanced Durability 156
9.3.5 Materials with Reduced Carbon Footprint and Embodied Energy 156
9.3.6 Material Miles 157
9.3.7 Sustainable Materials from Renewable, Recycled, and Recovered Sources 157
9.3.8 Materials with Higher Environmental Benignity 157
9.3.9 Materials with No Adverse Human Health Effects 157
9.3.10 Materials Enabling Healthy Natural Habitat 158
References 158
Index 159
