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Covering the major topics in lead-free soldering
Lead-free Soldering Process Development and Reliability provides a comprehensive discussion of all modern topics in lead-free soldering. Perfect for process, quality, failure analysis and reliability engineers in production industries, this reference will help practitioners address issues in research, development and production.
Among other topics, the book addresses:
* Developments in process engineering (SMT, Wave, Rework, Paste Technology)
* Low temperature, high temperature and high reliability alloys
* Intermetallic compounds
* PCB surface finishes and laminates
* Underfills, encapsulants and conformal coatings
* Reliability assessments
In a regulatory environment that includes the adoption of mandatory lead-free requirements in a variety of countries, the book's explanations of high-temperature, low-temperature, and high-reliability lead-free alloys in terms of process and reliability implications are invaluable to working engineers.
Lead-free Soldering takes a forward-looking approach, with an eye towards developments likely to impact the industry in the coming years. These will include the introduction of lead-free requirements in high-reliability electronics products in the medical, automotive, and defense industries. The book provides practitioners in these and other segments of the industry with guidelines and information to help comply with these requirements.
List of contents
List of Contributors xix
Introduction xxi
1 Lead-Free Surface Mount Technology 1
Jennifer Nguyen and Jasbir Bath
1.1 Introduction 1
1.2 Lead-Free Solder Paste Alloys 1
1.3 Solder Paste Printing 2
1.3.1 Introduction 2
1.3.2 Key Paste Printing Elements 2
1.4 Component Placement 5
1.4.1 Introduction 5
1.4.2 Key Placement Parameters 5
1.4.2.1 Nozzle 6
1.4.2.2 Vision System 6
1.4.2.3 PCB Support 6
1.4.2.4 Component Size, Packaging, and Feeder Capacity 6
1.4.2.5 Feeder Capacity 6
1.5 Reflow Process 7
1.5.1 Introduction 7
1.5.2 Key Parameters 7
1.5.2.1 Preheat 7
1.5.2.2 Soak 8
1.5.2.3 Reflow 8
1.5.2.4 Cooling 9
1.5.2.5 Reflow Atmosphere 9
1.6 Vacuum Soldering 9
1.7 Paste in Hole 10
1.8 Robotic Soldering 11
1.9 Advanced Technologies 12
1.9.1 Flip Chip 12
1.9.2 Package on Package 12
1.10 Inspection 13
1.10.1 Solder Paste Inspection (SPI) 13
1.10.2 Solder Joint Inspection 14
1.10.2.1 Automated Optical Inspection (AOI) 14
1.10.2.2 X-ray Inspection 15
1.11 Conclusions 16
References 17
2 Wave/Selective Soldering 19
Gerjan Diepstraten
2.1 Introduction 19
2.2 Flux 19
2.2.1 The Function of a Flux 19
2.2.2 Flux Contents 20
2.3 Amount of Flux Application on a Board 20
2.4 Flux Handling 21
2.5 Flux Application 21
2.5.1 Methods to Apply Flux (Wave Soldering) 21
2.5.2 Methods to Apply Flux (Selective Soldering) 23
2.6 Preheat 24
2.6.1 Preheat Process-Heating Methods 24
2.6.2 Preheat Temperatures 27
2.6.3 Preheat Time 28
2.6.4 Controlling Preheat Temperatures 28
2.6.5 BoardWarpage Compensation (Selective Soldering) 29
2.7 Selective Soldering 29
2.7.1 Different Selective Soldering Point to Point Nozzles (Selective Soldering) 29
2.7.2 Solder Temperatures (Selective Soldering) 30
2.7.3 Dip/Contact Times (Selective Soldering) 31
2.7.4 Drag Conditions (Selective Soldering) 31
2.7.5 Nitrogen Environment (Selective Soldering) 31
2.7.6 Wave Height Controls (Selective Soldering) 32
2.7.7 De-Bridging Tools (Selective Soldering) 32
2.7.8 Solder Pot (Selective Soldering) 33
2.7.9 Topside Heating during Soldering (Selective Soldering) 34
2.7.10 Selective Soldering Dip Process with Nozzle Plates (Selective Soldering) 34
2.7.11 Solder Temperatures for Multi-Wave Dip Soldering (Selective Soldering) 35
2.7.12 Nitrogen Environment (Selective Soldering) 35
2.7.13 Wave Height Control (Selective Soldering) 36
2.7.14 Dip Time - Contact Time with Solder (Selective Soldering) 36
2.7.15 Solder Flow Acceleration and Deceleration (Selective Soldering) 37
2.7.16 De-Bridging Tools (Selective Soldering) 37
2.7.17 Pallets (Selective Soldering) 38
2.7.18 Conveyor (Selective Soldering) 38
2.8 Wave Soldering 39
2.8.1 Wave Formers (Wave Soldering) 39
2.8.2 Pallets (Wave Soldering) 40
2.8.3 Nitrogen Environment (Wave Soldering) 40
2.8.4 Process Control (Wave Soldering) 41
2.8.5 Conveyor (Wave Soldering) 41
2.9 Conclusions 42
References 42
3 Lead-Free Rework 43
Jasbir Bath
3.1 Introduction 43
3.2 Hand Soldering Rework for SMT and
About the author
JASBIR BATH,
is the owner of Bath Consultancy LLC which provides consulting and training services in the electronics manufacturing industry. He was the Corporate Lead Engineer with Solectron Corporation/ Flex for ten years with a role involving tin-lead and lead-free solder process development. Previously he was a Technical Officer at ITRI (International Tin Research Institute/ Tin Technology) Ltd in the U.K.
Summary
Covering the major topics in lead-free soldering
Lead-free Soldering Process Development and Reliability provides a comprehensive discussion of all modern topics in lead-free soldering. Perfect for process, quality, failure analysis and reliability engineers in production industries, this reference will help practitioners address issues in research, development and production.
Among other topics, the book addresses:
* Developments in process engineering (SMT, Wave, Rework, Paste Technology)
* Low temperature, high temperature and high reliability alloys
* Intermetallic compounds
* PCB surface finishes and laminates
* Underfills, encapsulants and conformal coatings
* Reliability assessments
In a regulatory environment that includes the adoption of mandatory lead-free requirements in a variety of countries, the book's explanations of high-temperature, low-temperature, and high-reliability lead-free alloys in terms of process and reliability implications are invaluable to working engineers.
Lead-free Soldering takes a forward-looking approach, with an eye towards developments likely to impact the industry in the coming years. These will include the introduction of lead-free requirements in high-reliability electronics products in the medical, automotive, and defense industries. The book provides practitioners in these and other segments of the industry with guidelines and information to help comply with these requirements.
