Thermal Management and Interfacial Properties in High-Power GaN-Based Light-Emitting Diodes Employing Diamond-Added Sn-3 wt.%Ag-0.5 wt.%Cu Solder as a Die-Attach Material
Source: Journal of Electronic Materials, Volume 39, Number 12, December 2010 , pp. 2618-2626(9)
Abstract:The thermal management of high-power GaN-based light-emitting diodes (LEDs) soldered with Sn-3 wt.%Ag-0.5 wt.%Cu (SAC305) solder and diamond-added SAC305 solder was evaluated. Diamond addition was found to significantly reduce the surface temperature and total thermal resistance of the LEDs, revealing that diamond-added SAC305 solder is a promising die-attach material for high-power LED packaging. Interfacial reactions in the LED solder joints were also investigated. The thin Au wetting layer in the chip’s backside metallization was rapidly consumed in the initial stage of reflow, forming an AuSn4 phase at the interface. Subsequently, the AuSn4 phase detached from the interface, leading to dewetting of the SAC305 solder from the LED chip. To avoid dewetting, a new backside metallization of LED chips should be developed for SAC305 solder.
Document Type: Research Article
Affiliations: 1: Department of Chemical Engineering, National Chung Hsing University, Taichung, 402, Taiwan 2: Department of Chemical Engineering, National Chung Hsing University, Taichung, 402, Taiwan, Email: firstname.lastname@example.org 3: Department of Electro-Optical Engineering, National Cheng Kung University, Tainan, 701, Taiwan 4: Department of Materials Science and Engineering, National Chung Hsing University, Taichung, 402, Taiwan 5: Institute of Precision Engineering, National Chung Hsing University, Taichung, 402, Taiwan
Publication date: December 1, 2010