Analysis and Improvement of Moisture Absorption Failure of LED Devices

QIAN Fan; LI Xinling; LIANG Lecheng; ZHANG Wenbin; ZENG Xingrong

doi:10.3969/j.issn.1002-6150.2026.01.004

Abstract：Surface-mounted light-emitting diode(SMD LED)is widely used in commercial lighting,household lighting,backlight displays,and other fields.The combination of SMD LED and surface mount technology(SMT)not only achieves miniaturization and lightweighting of electronic products,but also significantly improves product reliability and production efficiency.However,the"popcorn effect"in the SMT soldering process is a problem that hinders the application of LED devices.This article has explored the relationship between moisture absorption rate and"popcorn effect"failure rate through simulation experiments,and examined the effects of packaging materials and brackets on the moisture absorption of LED devices.The results indicate that LED devices exhibit a"popcorn effect"when the moisture absorption rate exceeds 1 wt.‰.The moisture absorbed by the interface of LED bracket materials and structures is the main pathway for LED devices to absorb moisture,with moisture content accounting for 85.68%to 97.82%of the total moisture absorption.Based on the establishment of a moisture absorption failure rate model and commercial packaging materials,the effects of inorganic fillers and wetting agents on the"popcorn effect"have been investigated.The moisture absorption rate and failure rate of LED devices decrease with the increase of inorganic filler KMP590 in the packaging material,and the moisture absorption rate and failure rate achieve significant reductions of 35%and 64%,respectively.By adding KYC643 wetting agent,the failure rate was reduced from 79.17%to 52.08%,and the leveling time was shortened from 9.8 min to 3.5 min.This article provides directions for improving the performance of packaging materials,as well as studying the moisture absorption of LED devices,which also provides a theoretical basis for the failure analysis of the"popcorn effect".