Improved local thermal management of AlGaN-based deep-UV light emitting diodes

摘要

Local thermal management has a strong impact on the optical output power of AlGaN-based multiple-quantum-well deep-UV flip-chip light emitting diodes (LEDs). During the study, an improved methodology was developed by incorporating a metallic barrier layer of WSiN and a thermal interfacial layer of graphite/copper composite. The performance of these devices with improved thermal management and that of conventional flip-chip LEDs were compared. It was found that with the use of exotic material layers and modified Au-Sn bumps, the device heat dissipation capabilities were significantly enhanced. As a result, 70% enhancement in the optical output power of 250 μm disk LEDs (λ ～ 287 nm) was observed with a better device thermal stability.