The Improvement Study of UTS CIS Bevel Peeling Defect Based on the Application of SEM API

A bevel peeling defect formation during backside film remove processes on UTS CIS Logic products was introduced based on the using of SEM API function. The reason of the formation and its affect factors of peeling defect were studied in this paper. Chemical 1 with high concentration was used to clear up backside film, LTO/Poly/SIN, in backside remove processes, these acids seeped into the metal film body, then eroded metal film into bump, through the interfaces of films bevel remained. The metal bump would break down to peeling source after 4days’ waiting time. Bevel etch before wafer package, were studied to induce bevel peeling. The experiment results showed that, peeling defect would be free when bevel etch process was added.