Die attach and wirebond systems for high temperature electronics

Summary form only given. Creating a reliable electronic system that can operate at temperatures in excess of 200°C requires more than just developing ICs that can function at these temperatures. It also requires developing packaging technologies that can accommodate device operation. Three critical packaging related failure mechanisms in components and modules at high temperatures are intermetallic formation at the wire bonds, wire annealing at the midspan, and die attach fatigue at the die to substrate interface. This paper will describe the relative reliability of various die attach materials and wirebonding systems proposed for high temperature electronics. Results of die shear, bond shear, and wire pull strength measurements on die attach and wirebond materials, respectively, after aging for 1000 hours at 260°C and after temperature cycling from -55°C to 260°C for 1000 cycles will be presented. These results will be analyzed using a new viscoplastic shear stress and damage model for die attach fatigue and a new model for wire annealing which can be used to assess the susceptibility of high temperature electronic modules to failure by these mechanisms