Comprehensive Investigation of Insufficient IMC in SOIC Through Advanced Statistical Analysis

In the context of copper ball bonding in semiconductor packaging, an insufficient IMC implies an inadequate intermetallic connection between the aluminum bond pad and the copper ball. This deficiency introduces the potential risk of ball lift issue, thereby adversely affecting the product's reliability performance. The impacted package type is the Small Outline Integrated Circuit (SOIC), primarily employed in automotive applications. It is imperative that the IMC meets compliance standards immediately upon assembly (0 hours), rendering non-compliance unacceptable. Consequently, ensuring a compliant IMC is imperative during the project development phase. This paper delves into the multifaceted factors contributing to insufficient IMC occurrences, with a particular focus on the role of wire bonder Machine-to-Machine (MTM) variation during the wire bonding process. Furthermore, it outlines strategies for addressing this issue, encompassing measures such as precise MTM calibration to achieve stable and dependable output responses.