This book focuses on the design, materials, process, fabrication, quality, reliability, fatigue, fracture, and artificial intelligence (AI) assisted in chiplets and heterogeneous integration. Both principles and engineering practice have been addressed, with more emphasis placed on engineering practice. This is achieved by providing in-depth study on a number of major topics such as Cu interconnects, glass-core substrate, 3D heterogeneous integration of photonic IC and electronic IC, and combining simulation design with AI technology to effectively apply it to semiconductor packaging. This book can benefit researchers, engineers, and graduate students in fields of electrical engineering, mechanical engineering, materials sciences, and industry engineering, etc.