Assessment of backside processes through die strength evaluation

While trends in semiconductor packages continue toward a decrease in overall package size and an increase in functionality and performance requirements, the challenge of maintaining and improving reliability is a critical aspect. In practice, die strength can be adversely affected during various manufacturing processes. The process of die thinning can significantly affect the material's characteristics and reliability. A realistic understanding of the significance of processing on die strength is gained through the study of the actual, processed component. This work outlines a comparative analysis of various thinning processes and their effects on die strength. Characterization of die damage resulting from processing is followed by experimentation utilizing the ball-breaker test methodology to determine die strength with respect to die surface conditions. Through failure analysis of fractured dies, the root causes of die fracture are detected. This information serves as a basis for process selection to meet the trends and needs of a reliable package, and for the development and improvement of existing processes.

[1]  Mali Mahalingam,et al.  "Measurement of Silicon Strength as Affected by Wafer Back Processing" , 1987, 25th International Reliability Physics Symposium.