P. Quintero 1 and F. P. McCluskey2
1Department of Mechanical Engineering, University of Puerto Rico - Mayaguez, Mayaguez, PR, 00681
2CALCE, Center for Advanced Life Cycle Engineering, Department of Mechanical Engineering, University of Maryland, College Park, Maryland 20742, USA
The demand for electronics capable of operating at temperatures above the traditional 125 oC limit continues to increase. Devices based on wide band gap semiconductors have been demonstrated to operate at temperatures up to 500 oC, but packaging remains a major hurdle to product development. Recent regulations, such as RoHS and WEEE, increase the complexity of the packaging task as they prohibit the use of certain materials in electronic products such as lead (Pb), which has traditionally been used in high temperature solder die attach. In this investigation, an Ag-In solder paste is presented as a die attach alternative for high temperature applications. The proposed material has been processed by a transient liquid phase sintering method resulting in an in situ alloying of its main constituents. A shift of the melting point of the system, confirmed by differential scanning calorimetry, provided the basis for a breakthrough in the typical processing temperature rule. The mechanical integrity and reliability of this novel attachment material is discussed.