What Is Micro Welding?

This book explains the development of microelectronic welding technology and the impact of lead-free from the basic concepts of microelectronic welding, welding materials and properties, welding processes and applications. The basic theory and practical application of microelectronics welding are emphasized, including chip welding technology, surface assembly (mounting) technology and solder joint reliability.

Microelectronic welding

This book can be used as a textbook for microelectronic welding technology for undergraduates and graduates of electronic packaging majors in colleges and universities, and it can also be used as a reference book for materials, machinery, microelectronics students and related workers.

With the development of the semiconductor microelectronics industry, the electronics industry technology in countries around the world has achieved unprecedented development. At the same time, the world's major semiconductor and electronics companies have come to China to invest and build factories, especially the industrial areas represented by the "Yangtze River Delta" and "Pearl River Delta". Electronic packaging technology, semiconductor circuit design and manufacturing are collectively called semiconductor microelectronics The three pillars of the industry are extremely important as the main course of semiconductor production, and are the indispensable industrial cornerstones of the modern information society. Microelectronic packaging technology not only involves a large number of new processes and technologies, but also involves a large number of new functional materials. It has brought many new topics and opportunities for development and innovation to materials science and engineering, and also provided many new methods for other scientific innovations New ways. This has undoubtedly directly stimulated the rapid expansion of China's semiconductor and electronic packaging industry.

Microelectronic welding technology is the key to the advanced manufacturing technology of electronic products. It is the main technology of electrical interconnection in the manufacture of electronic products. It is the representative technology of the development of electronic packaging and assembly technology to the current stage. The main technical means of component or microsystem assembly and interconnection is also an emerging interdisciplinary comprehensive high-tech developed by the integration of traditional chip interconnection technology, device packaging technology, surface assembly technology, and three-dimensional assembly technology.

With the rapid development of China's electronic packaging industry, the industry's demand for microelectronics welding technology is also very urgent, so microelectronics welding technology books are urgently needed. The book "Microelectronic Welding Technology" prepared by Nanjing University of Aeronautics and Astronautics and Harbin Institute of Technology focuses on the development of microelectronic welding technology, basic applications of new welding processes and materials, and solutions to related defects. This book focuses on the basic theory and practical application of microelectronic welding. It has practical value for undergraduates and graduate students majoring in electronics packaging as a professional course book. It also has good reference value for technical workers in related fields.

Foreword

Chapter 1 Microelectronic Welding Technology

1.1 Overview of Microelectronic Welding Technology

1.1.1 The concept of microelectronic welding technology

1.1.2 Overview of Microelectronic Packaging and Assembly Technology

1.2 Development of Microelectronic Welding Technology

1.2.1 Development of Microelectronic Packaging

1.2.2 Chip soldering technology

1.2.3 soldering technology

1.3 Development of Microelectronic Welding Materials

1.3.1 Proposal and Process of Lead-free

1.3.2 Definition and performance requirements of lead-free solder

1.3.3 Research Status and Development Trend of Lead-free Solder

1.4 Problems in Lead-free Electronics Assembly

1.4.1 Requirements for lead-free materials

1.4.2 Requirements of Lead-free Process for Electronic Assembly Equipment

Thinking questions

references

Chapter 2 Chip Soldering Technology

2.1 wire bonding technology

2.1.1 Bonding Principle

2.1.2 bonding process

2.2 Carrier tape automatic bonding technology

2.2.1 Bonding Principle

2.2.2 Production of chip bumps

2.2.3 In-lead and outer-lead bonding technology

2.3 Flip Chip Bonding Technology

2.3.1 Bonding Principle

2.3.2 Bonding Technology Implementation Process

Thinking questions

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Chapter 3 Basic Principles of Soldering

3.1 Basic principles and characteristics of soldering

3.2 Oxidation of solder and substrate

3.2.1 oxidation mechanism

3.2.2 Surface oxidation of liquid solder

3.2.3 Deoxidation mechanism

3.3 Wetting and spreading of solder

3.3.1 The concept of wetting

3.3.2 Factors affecting solder wetting

3.3.3 Weldability evaluation method

3.4 Interfacial reaction of microelectronic welding

3.4.1 Basic Process of Interfacial Reaction

3.4.2 Interface reactions and organization

Thinking questions

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Chapter 4 Materials for Microelectronic Welding

4.1 Solder alloy

4.1.1 Requirements for Microelectronic Welding Solder of Electronic Products

4.1.2 Tin-Lead Solder

4.1.3 Lead-free solder

4.2 Flux

4.2.1 Requirements for flux

4.2.2 Classification of Flux

4.2.3 Common flux

4.2.4 Principles of using flux

4.3 Surface coating of printed circuit boards

4.3.1 PCB surface coating system

4.3.2 Comparison of Several Typical PCB Surface Coating Processes

4.4 Lead-free surface plating of electronic components

4.4.1 Pure Sn plating

4.4.2Sn? Cu alloy coating

4.4.3Sn? Bi alloy coating

4.4.4 Ni / Pd and Ni / Pd / Au alloy coatings

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Chapter 5 Microelectronic Surface Assembly Technology

5.1SMT Overview

5.1.1 What SMT involves

5.1.2 Main Features of SMT

5.1.3 Comparison of SMT and THT

5.1.4 SMT process requirements and development direction

5.2 SMT assembly solder, adhesive and cleaning agent

5.2.1 Solder

5.2.2 Binder

5.2.3 Cleaning agent

5.3 SMC / SMD placement process technology

5.3.1 SMC / SMD mounting method

5.3.2 Main factors affecting accurate placement

5.4 Microelectronic welding methods and characteristics

5.4.1 Introduction to Microelectronic Welding

5.4.2 Wave soldering

5.4.3 Reflow welding

5.5 Cleaning process technology

5.5.1 Types and sources of pollutants

5.5.2 Cleaning principle

5.5.3 Main factors affecting cleaning

5.5.4 Cleaning process and equipment

5.6SMT inspection and repair technology

5.6.1 Overview of SMT Detection Technology

5.6.2 SMT incoming inspection

5.6.3 SMT component repair technology

Thinking questions

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Chapter 6 Process Defects in Microelectronic Welding

6.1 Melting and solidification during brazing

6.1.1 Characteristics of solder joint solidification

6.1.2 Means of detecting the solidification of solder joints

6.2 Solder joint peeling and pad lift

6.2.1 Definition of solder joint peeling

6.2.2 Mechanism of solder joint peeling

6.2.3 Preventive measures for solder joint peeling

6.3 Black disk

6.3.1 Principles of chemical nickel-gold

6.3.2 Influencing factors and control measures of black disk formation

6.4 Welding and cold welding

6.4.1 Welding

6.4.2 Cold welding

6.5 Non-wetting and de-wetting

6.5.1 Definition

6.5.2 Formation Principle

6.5.3 Solutions

6.6 Bursting and delamination

6.6.1 Reasons for bursting

6.6.2 Overview of PCB Failure Analysis Technology

6.6.3 Application of Thermal Analysis Technology in PCB Failure Analysis

6.7 Hollow

6.7.1 Formation and classification of holes

6.7.2 Causes and Improvements of Hollowness

6.7.3 Ball and socket defects

6.7.4 Measures to suppress ball and socket defects

Thinking questions

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Chapter 7 Reliability of solder joints in microelectronic welding

7.1 Reliability concepts and influencing factors

7.1.1 Reliability Concept

7.1.2 Scope of reliability research

7.2 Thermomechanical reliability of solder joints

7.2.1 Accelerated test method

7.2.2 Numerical Simulation of Reliability Design

7.3 Electromigration characteristics

7.3.1 Definition of electromigration

7.3.2 Electromigration characteristics of different solders

7.4 Tin Whiskers

7.4.1 Morphology of tin whiskers on the surface of lead-free solder

7.4.2 Driving Forces and Dynamics of Growth Process

7.4.3 Inhibition of tin whisker growth

7.4.4 Accelerated Experiment of Tin Whisker Growth

Thinking questions

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Appendix abbreviations in Chinese and English