Pushing toward the limits of acceleration: Example on wire-bond assemblies

Abstract In harsh environments, materials are used at their strength limits, and it might be difficult to accelerate the ageing in reliability tests without modifying the failure mechanisms. The paper presents a methodology used to define the maximal acceleration temperature for ageing of wire-bonds aimed to be used at an operational temperature up to 200 °C. Reliable wire bond interconnects are essential despite of intermetallic growth accelerated as the temperature increases. Wire bonds shown reliable long term performance at 250 °C and the possibility of accelerating the ageing up 300 °C was demonstrated. Beyond this temperature a new ageing mechanism was identified.

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