大功率LED纳米银烧结界面热阻和发光性能  

Thermal Resistance and Luminescence Performance of Nano-Silver Sintered Interface in High-Power LED

作　　者：梁仁瓅 刘佳欣 赵九洲 彭洋 王新中[2] 杨军[1] Liang Renli;Liu Jiaxin;Zhao Jiuzhou;Peng Yang;Wang Xinzhong;Yang Jun(Shenzhen Institute for Advanced Study,University of Electronic Science and Technology of China,Shenzhen 518110,Guangdong,China;Information Technology Research Institute,Shenzhen Institute of Information Technology,Shenzhen 518172,Guangdong,China;School of Mechanical Science&Engineering,Huazhong University of Science and Technology,Wuhan 430074,Hubei,China;School of Aerospace Engineering,Huazhong University of Science and Technology,Wuhan 430074,Hubei,China)

机构地区：[1]电子科技大学(深圳)高等研究院,广东深圳518110 [2]深圳信息职业技术学院信息技术研究所,广东深圳518172 [3]华中科技大学机械科学与工程学院,湖北武汉430074 [4]华中科技大学航空航天学院,湖北武汉430074

出　　处：《光学学报》2023年第2期158-166,共9页Acta Optica Sinica

基　　金：中国博士后科学基金(2021M700692);深圳市科技计划项目(JSGG20201102152403008);深圳市科技计划项目(JSGG20210802154213040);创新强校项目(PT2020C002)。

摘　　要：利用纳米银烧结工艺制备大功率LED,重点探究了纳米银键合层的界面热阻及器件发光性能。通过将纳米银膏在不同温度下烧结,系统地研究了烧结温度对纳米银烧结后电阻率及接头剪切强度的影响,并分析了烧结后银膏的晶体结构及接头断口微观形貌。结果表明,接头键合强度和银膜导电率均随纳米银烧结温度的升高而增大。实验中还对比分析了纳米银烧结LED和传统锡银铜(SAC305)焊膏封装LED的界面热阻、结温以及发光性能。与纳米银烧结LED样品相比,传统焊膏封装LED的界面热阻和结温分别提高了8.9%和29.6%,说明纳米银键合层拥有更好的导热性并可及时为芯片散热降温。此外,通过高温老化实验,深入探讨了不同焊膏烧结LED的界面热阻及发光效率变化。实验表明,经过100℃下点亮500 h,纳米银和传统焊膏烧结LED样品的总热阻分别增大了0.03 K/W和4.28 K/W,但纳米银键合层界面热阻比老化前有所降低,同时纳米银烧结LED样品在不同电流下的发光效率始终高于传统焊膏封装LED样品。Objective Light emitting diodes(LEDs)are semiconductor light emitting devices based on the electroluminescence principle of p-n junction.Due to the advantages of high lighting efficiency,long life,environmental protection,energy saving,and compact structure,they have been widely used in the field of lighting and backlight display,such as road lighting,indoor lighting,automobile headlights,TV backlight,and mobile phone flash.With the increasing demand for lighting and display,LED technology is developing toward high power and high density.Therefore,luminescence performance has become an important indicator.Research shows that the luminescence performance of LEDs can be improved by employing the embedded ceramic circuit board technology and doping metals and other chemical compounds.However,the influence of LED heat dissipation on luminescence performance cannot be ignored.As the electro-optic conversion efficiency of LED is less than 60%,part of the input electric energy is converted into heat,and more heat is generated by the LED chip with the increase in the input power.For avoiding thermal damage to LED chips under high temperatures,it is significant to enhance the heat dissipation performance of LEDs,which can thereby improve the luminescence performance of high-power LEDs.This paper uses nano-silver paste for high-power LED packaging and systematically investigates the thermal resistance and luminescence performance of a nano-silver sintered interface in a highpower LED.Further,the paper analyzes the resistivity,bonding strength,and micromorphology of the nano-silver bonding layer at different sintering temperatures and compares the thermal resistance,junction temperature,and optical properties of LED devices sintered with nano-silver paste and Sn-Ag-Cu(SAC)solder.Methods The nano-silver paste in this study is the silver paste after pressureless sintering.The chip used is a vertically packaged high-power blue LED chip with a direct plated copper(DPC)ceramic substrate,and the packaging substrate is a hexagonal

关 键 词：材料 大功率LED 光热性能 发光稳定性 纳米银烧结 界面热阻 

分 类 号：O436[机械工程—光学工程]