近紫外LED封装器件的热稳定性及可靠性

Thermal Stability and Reliability Analysis of Ultraviolet Light-emitting Diode Packages

紫外发光二极管(紫外LED)已经在许多超越照明领域展示出了特殊的应用优势,例如健康医疗、消毒杀菌、环保及传感等领域。本文采用仿真和实验相结合的方法研究了具有不同封装结构的近紫外LED封装器件的热稳定性,并对其进行了高温老化可靠性测试评估。研究结果表明:LED器件的辐射功率和正向电压随温度的升高而下降,其中,具有倒装结构的器件下降趋势明显小于正装结构,这表明其热稳定性较好;经过55℃恒温额定电流条件下的可靠性测试发现具有倒装结构的器件光-色特性衰减速率小于正装器件。通过本文研究可以得出结论:具有低热阻、小尺寸等优点的的倒装封装结构有助于提高近紫外LED器件的光-热稳定性和可靠性。

With many advantages,ultraviolet light-emitting diode(UV LED) packages have been widely applied in many beyond-lighting areas,including healthcare,disinfect,environmental protection and sensing. By using both simulations and experiments,this paper investigates the thermal stabilities and high temperature ageing reliability of near UV LED devices with three different packaging structures. The results indicate that,the radiation power and forward voltage of all samples show a downward trend with the increase of substrate temperature,but the downward trend of UV LED with flip-chip packaging structure is significantly less than that of wire bonding UV LEDs;the reliability test under the 55 ℃ and constant rated current condition shows that the luminous flux,radiation power and color coordinate of flip-chip type UV LEDs are relatively stable than those of wire-bonding type UV LEDs. Generally,this study can conclude that the flip-chip packaging structure with lower thermal resistance,small size and long life can improve the optical and thermal stabilities and reliability of UV LEDs.