I. Introduction
Microstructure analysis is vital in understanding reliability issues of electronic packages and physical failures of interconnectors [1]-[3]. Many studies have revealed that mechanical and reliability issues of microelectronic packaging interconnectors are closely related to the formation and growth of intermetallic compounds (IMCs) at the interface of jointing metals, typically between metals of Au/Al, Al/Cu, and Sn/Cu [1]-[3]. Many IMCs can embrittle or crack microelectronic devices due to their brittle nature and low fracture toughness [2]-[4]. In a semiconductor characterization laboratory, phase identification and phase distribution analysis on IMC samples have become a routine but important job for failure analysis and quality risk assessment [2]-[4].