SMT设备原理与应用-第一章_概述.ppt

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1、SMT设备原理与应用Principle and Application of SMT Equipment2010.92021/9/171本课程主要讲述内容，时间安排，考试安排，实验，辅导和平时考勤SMT工艺流程和相关设备SMT设备概述 Summarize2021/9/172SMT概述与发展趋势 4学时 summary and trend焊膏组成与印刷的方式 4学时 solder paste composition and printing technology印刷机原理与应用 6学时 principle and application of printer 贴片机原理与设备 12学时 prin

2、ciple and application of placement machines波峰焊原理与应用 6学时 principle and application of wave soldering oven再流炉原理与应用 6学时 principle and application of reflow soldering oven检测设备 4学时 inspection equipment本课程的主要内容Including2021/9/173SMT生产线参观（印刷机、再流炉）2学时 Visiting SMT production line(printer,reflow oven)贴片机编程原理

3、；2学时 Mounter(placement machines)program贴片设计性实验。2学时 Placement process design experiment实验内容 experiment content2021/9/174期末考试：开卷，占总分60%平时：20%（作业50%+考勤40%+特别贡献10%）实验：20%考试方式 test rules2021/9/175联系方式：，辅导时间和地点：地点：时间：每周辅导时间和联系方式2021/9/176SMT概述与发展趋势Summary and Trends2021/9/177Surface mount technology was d

4、eveloped in the 1960s and became widely used in the late 1980s.Much of the pioneering work in this technology was by IBM.Components were mechanically redesigned to have small metal tabs or end caps that could be directly soldered directly soldered to the surfacesurface of the PCB.Components became m

5、uch smaller and component placement on both sides of a board became far more common with surface mounting than through-hole mounting,allowing much higher circuit densities.Surface mounting lends itself well to a high degree of automation,reducing labor cost and greatly increasing production rates.SM

6、Ds can be one-quarter to one-tenth the size and weight,and one-half to one-quarter the cost of equivalent through-hole parts.SMT技术发展历史和优点History and benefits2021/9/178SMp DIALECTExpanded FormChinesSMDSurface Mount Devices(active,passive and electromechanical components)表面贴装器件SMTSurface Mount Technol

7、ogy(assembling and montage technology)表面贴装技术SMASurface Mount Assembly(module assembled with SMT)表面装配SMCSurface Mount Components(components for SMT)表面贴装组件SMPSurface Mount Packages(SMD case forms)表面贴装元件封装形式SMESurface Mount Equipment(SMT assembling machines)表面贴装设备常用术语Terms2021/9/179Chip Resistor2021/9/

8、1710MELFMetal Electrode Face resistors2021/9/1711chip capacitor2021/9/1712chip inductor2021/9/1713discrete semiconductor2021/9/1714SO2021/9/1715Chip CarrierPlastic Leadless Chip CarrierLeadless Ceramic Chip Carrier2021/9/1716Quad Flat PackageBall grid array2021/9/1717SOSmall Outline(4 to 28 pins)小外形

9、结构SOPSmall Outline Package(case)小外形封装SODSmall Outline Diode小外形封装分立二极管SOTSmall Outline Transistor小外形封装分立三极管SOICSmall Outline Integrated Circuit小外形集成电路CCChip Carrier芯片载体LCCLeadless Chip Carrier无引线芯片载体PLCCPlastic Leadless Chip Carrier塑封无引线芯片载体LCCCLeadless Ceramic Chip Carrier无引线陶瓷芯片载体MELFMetal Electrod

10、e Face Bonding金属电极柱形电阻QFPQuad Flat Package四边引脚扁平封装BGAball grid array球栅阵列封装2021/9/1718The solder joint configurations of the IC packages can be represented by five major categoriesGullwing leads 翼型引脚J-lead design J型引脚Butt-leads 对接引脚leadlessBall-lead 球形引脚2021/9/1719Types of surface mount assemblytechn

11、ology表面组装技术的类型2021/9/1720Type I surface mount boards have SMCs onlyonly for both sides of the boards2021/9/1721Type II boards have both SMCs and THCs both SMCs and THCs on one side of the board and chip components on the other side2021/9/1722Type III SMT have THCsTHCs on one side of the board and ch

12、ip components on the other side2021/9/1723Surface mount soldering process表面组装焊接类型2021/9/1724Wave soldering适用于通孔装配技术THT和通孔元件THC为了减小阴影效应（shadowing effect）,通常采用双波峰技术（dual wave）,前面是湍流波（turbulent wave）用于确保所有的引脚润湿，后面的层流波（laminar wave）用于焊接波峰焊仅适用于小的SMCs，大的SMCs和行间距依然是存在桥接（bridge）和焊锡不足等问题2021/9/1725reflow sol

13、dering使用预配置好的焊膏（solder paste）进行焊接，焊膏本身可以作为粘接剂焊膏用模版印刷到PCB上采用贴片机进行元件放置在回流炉（reflow oven）中多个温区进行整体加热焊接reflow soldering2021/9/17261.solder paste serves not only as a solder material,but also as a glue.2.the deposition of solder paste is usually conducted by the stencil or screen printing,dispensing,or pi

14、n-transferring processes.The premetered deposition of solder material onto the sites to be soldered ensures a consistent solder volume for the joints,and accordingly eliminates the insufficient solder volume problems due to the shadowing effect encountered by wave soldering.In addition,this premeter

15、ed solder deposition also reduces the incidence of bridging.Advantages of solder paste technology in SMT2021/9/17273.the use of mass reflow process allows a well-controlled graduate heating profile,thus eliminating potential damage of the SMCs due to the thermal shock caused by the wave soldering4.t

16、he use of solder paste allows the possibility of step soldering.5.the soldering performance of solder paste is not sensitive to the type of solder mask used on the PCBs.For the wave soldering process,a solder mask with a smooth finish is found to cause solder ball and bridging problems.Advantages of

17、 solder paste technology in SMT2021/9/1728技术发展趋势Surface mount technology trends2021/9/1729Technology driving forceSmallerFasterHigher complexityLower powerLower cost2021/9/1730Speedprocessing speed increases approximately five times in every 5 years;results from reduction in both on-chip delay in se

18、miconductors and packaging delaythis improvement in speed is closely associated with miniaturization of IC components,as demonstrated by the simultaneous reduction in line widths2021/9/17312021/9/1732IC transistor integrationThe complexity of semiconductor chips can be measured by transistor integra

19、tion.microprocessor integration has increased by 2000 since its introduction in 1970This increase in complexity of semiconductor chips essentially drives the evolution of corresponding packaging and assembly technologyComplexity2021/9/1733Pin count numberthe pin count number will increase almost 100

20、 from the through-hole technology in the early 1980s to modules/system packaging in the late 1990s.Complexity2021/9/1734IC feature sizeDiscrete component sizeMiniaturization2021/9/1735Area array packages2021/9/1736Pressure of speed,complexity,and miniaturization have driven the peripheral package de

21、sign down to 0.3mm(16mil)pitch for QFP 17the rapidly increasing defect rate associated with miniaturization of peripheral design was recognized very quickly as the bottleneck in further improvements in performance.the assembly defect rate(ppm)of QFP is a strong function of the pitch size.The defect

22、rate is 25 to 40 ppm for 50mil pitch,and gradually increases to 25 to 100 ppm for 30mil pitch and 40 to 233 ppm(5 sigma control)for 25mil pitch.The defect rate becomes prohibitively high,100 to 2300 ppm,for 20mil pitch.This high defect rate is primarily associated with the vulnerability of the slim,

23、thin gullwing leads of QFP toward handling.The high precision required for the ultra-fine-pitch component placement as well as solder paste deposition further aggrevates the problem.ball grid array(BGA)2021/9/1737ball grid array(BGA)2021/9/1738ball grid array(BGA)2021/9/1739chip scale packages(CSP)A CSP is an IC area array package with size no larger than 1.2 of IC in the linear dimension,or no larger than 1.5 of IC in area.2021/9/1740Flip chip2021/9/1741