Electronic products are continuously shrinking in size, and more chip functionalities are being integrated into compact packages. In this integration, System in Package (SiP) technology is widely employed, allowing various types of heterogeneous components to be integrated into a single package. SiP packages utilize fine-pitch flip chips and ultra-small passive components, requiring solder paste with even smaller particles for their assembly. Therefore, soldering processes necessitate the use of solder paste composed of extremely fine powder.

Adhesive formulation for semiconductor packaging is a technology to design organic-based adhesive materials used in semiconductor packaging and electronic component assembly, tailored to specific purposes such as electrically conductive adhesives, thermally conductive adhesives, insulating adhesives, underfills, and encapsulants. This includes adhesive formulation technology that determines adhesion strength and mechanical properties through organic resins, curing agents, catalysts, coupling agents, and filler blending technology that determines thermal and electrical performance such as thermal conductivity, coefficient of thermal expansion, and electrical conductivity by metal/ceramic fillers. Recently, the introduction of machine learning has also enabled the implementation of adhesive formulation optimization with minimal experimentation.

Epoxy adhesives are cost effective joining materials showing the properties of high adhesion, mechanical strength, heat and chemical resistance. Through the various formulation techniques, the wide range of viscoelastic behavior, curing behavior and cured properties can be achieved due to the many kinds and large number of ingredients available for epoxy. Recent researches about epoxy adhesives include maximizing the content of heat conductive fillers for the semiconductor packaging area issues and synthesizing 2K room temperature curing type epoxy toughening agent and maximizing the unbreakable property for the dissimilar joining and cryogenic applications in the heavy industry area.