Constructional Analysis for Qfn Stacked Die Failure Identification

The electronic industry has always set for the highest standards in quality and reliability. To ensure the reliability of final semiconductor products, evaluation and characterization at process development and product stage are conducted. In this paper, constructional analysis (CA) technique is used as a tool to determine failure mode in QFN stacked die package that will affect reliability. The procedure in CA involves package decapsulation, cross sectioning and SEM analysis. Failure mode and its causes will also be addressed. INTRODUCTION In constructional analysis (CA) technique, decapsulation and cross sectioning through QFN packages is usually done to reveal internal feature and materials used. Figure 1 shows the flow diagram of CA procedures for QFN stacked die failures identification. Procedure 1: Cross-sectional analysis. Procedure 2: Decapsulation. Cold Mounting Package Decapsulation Mechanical Polishing SEM analysis