26 Surface mount Technology 26.1 Introduction 26.2 Definition and Considerations Considerations in the Implementation of SMT 26.3 SMT Design, Assembly, and Test Overview 26.4 Surface Mount Device(SMD)Definitions 26.5 Substrate Design Guidelines 26.6 Thermal Design Considerations 26.7 Adhesive 26.8 Solder Paste and Joint Formation 26.9 Parts Inspection and Placement 6.10 Reflow Soldering Glenn r. blackwell 26.11 Cleanin Purdue University .6. 12 Prototype Systems 26.1 Introduction This section on surface mount technology(SMT)will familiarize the reader with the process steps in a successful SMT design. The new user of SMT is referred to Mims [1987] and Leibson [1987] for introductory material. Being successful with the implementation of SMT means the engineers involved must commit to the principles of concurrent engineering. It also means that a continuing commitment to a quality techniques is necessary, whether that is Taguchi, TQM, SPC, DOE, another technique, or a combination of several quality techniques, lest you too have quality problems with SMT(Fig. 26.1) 26.2 Definition and Considerations SMT is a collection of scientific and engineering methods needed to design, build, and test products made with electronic components that mount to the surface of the printed circuit board without holes for leads [ Higgins 1991]. This definition notes the breadth of topics necessary to understand SMT, and also clearly says that the successful implementation of SMT will require the use of concurrent engineering [ Classon, 1993; Shina, 1991] Concurrent engineering means that a team of design, manufacturing, test, and marketing people will concern hemselves with board layout, parts and parts placement issues, soldering, cleaning, test, rework, and packaging before any product is made. The careful control of all these issues improves both yield and reliability of the final product. In fact, SMT cannot be reasonably implemented without the use of concurrent engineering, and/or the principles contained in Design for Manufacturability(DFM)and Design for Testability(DFT), and therefore any facility that has not embraced these principles should do so if implementation of SmT is its goal c 2000 by CRC Press LLC© 2000 by CRC Press LLC 26 Surface Mount Technology 26.1 Introduction 26.2 Definition and Considerations Considerations in the Implementation of SMT 26.3 SMT Design, Assembly, and Test Overview 26.4 Surface Mount Device (SMD) Definitions 26.5 Substrate Design Guidelines 26.6 Thermal Design Considerations 26.7 Adhesives 26.8 Solder Paste and Joint Formation 26.9 Parts Inspection and Placement Parts Placement 26.10 Reflow Soldering Post-Reflow Inspection 26.11 Cleaning 26.12 Prototype Systems 26.1 Introduction This section on surface mount technology (SMT) will familiarize the reader with the process steps in a successful SMT design. The new user of SMT is referred to Mims [1987] and Leibson [1987] for introductory material. Being successful with the implementation of SMT means the engineers involved must commit to the principles of concurrent engineering. It also means that a continuing commitment to a quality techniques is necessary, whether that is Taguchi, TQM, SPC, DOE, another technique, or a combination of several quality techniques, lest you too have quality problems with SMT (Fig. 26.1). 26.2 Definition and Considerations SMT is a collection of scientific and engineering methods needed to design, build, and test products made with electronic components that mount to the surface of the printed circuit board without holes for leads [Higgins, 1991]. This definition notes the breadth of topics necessary to understand SMT, and also clearly says that the successful implementation of SMT will require the use of concurrent engineering [Classon, 1993; Shina, 1991]. Concurrent engineering means that a team of design, manufacturing, test, and marketing people will concern themselves with board layout, parts and parts placement issues, soldering, cleaning, test, rework, and packaging, before any product is made. The careful control of all these issues improves both yield and reliability of the final product. In fact, SMT cannot be reasonably implemented without the use of concurrent engineering, and/or the principles contained in Design for Manufacturability (DFM) and Design for Testability (DFT), and therefore any facility that has not embraced these principles should do so if implementation of SMT is its goal. Glenn R. Blackwell Purdue University