Preparation Of High Efficacy White LED Devices In Chip Scale Package

The development direction of solid-state light sources tends to be more energy-efficient,traditional LEDs with low power,low light efficiency,large size,and high thermal resistance have become more and more difficult to meet the demand,which requires us to seek new ways to achieve performance.Chip-scale packaging can significantly improve performance.In terms of structural characteristics,chip-scale packaged LEDs have a significantly smaller size and a lower thermal resistance than traditional packaged LEDs.At the same time,the 180-degree wide light-emitting angle and other characteristics determine its wider application.Based on the actual needs of high-power LEDs,this thesis explores the design and development of a chip-scale packaged LED with high power,high luminous efficiency,high mechanical strength and low thermal resistance.Horizontal comparison and analysis with traditional packaged LEDs in terms of device fabrication,thermal performance,and optoelectronic performance.Firstly,this thesis introduces the packaging principle and development of LED,and introduces the structure of several mainstream packaging forms and the process flow.It can be seen that the chip-level package LED has obvious advantages compared with the traditional package LED,and the chip-scale package LED has a good application prospect.Secondly,a chip-level LED package is designed and prepared.The first is the device fabrication,including the process of resorting,molding of the reflective layer,phosphor spraying,and sawing.Then,the test and sorting after the package is completed.The related problems and phenomena encountered in the process flow were analyzed and summarized,and the chip-level packaged devices were analyzed in detail from the preparation process.Finally,the relevant parameters of several package forms are compared and analyzed.Combined with the more popular packaging forms,the thermal performance and optical performance of the devices are quantitatively analyzed respectively,which proves that the luminous efficiency and heat dissipation capability of the chip-scale package structure are superior in today's popular technology.