Copper wirebond package decapsulation technique using mixed acid chemistry

Copper (Cu) wirebond technology in IC packaging has become popular these days due to its better characteristic and cost compare to Gold (Au). Nonetheless, failure analysis remains to be very challenging as Cu is easily dissolved when it is reacted with fuming nitric acid used during standard decapsulation process. Hence, by utilizing enhanced manual decapsulation technique with mixture of fuming nitric acid and concentrated sulfuric acid at low temperature, successful Cu wire package decapsulation happen to be reproducible mainly for die level failure analysis purposes.