Epoxy Resin for Semiconductor Packaging: The Core Material of Modern Electronic Components

Electronic components form the foundation of the electronics industry, and packaging technology is crucial for ensuring their proper operation. Whether dealing with discrete components or semiconductor devices such as Large-Scale Integrated (LSI) and Very Large-Scale Integrated (VLSI) circuits, protective packaging and insulation are essential to shield them from external factors—such as dust, moisture, shock, vibration, and chemical substances—and to guarantee their functionality. Packaging materials represent a major expense in semiconductor device manufacturing, ranking second only to silicon wafers and exceeding the costs associated with lead frames and photoresists. In terms of material costs for VLSI manufacturing, packaging materials account for 23% to 24% of the total. In the era of rapid semiconductor technological advancement, packaging goes beyond mere insulation; it significantly influences component dimensions, heat dissipation, and overall costs. Packaging methods have become a critical factor affecting performance, sometimes even serving as a driver for performance improvements. Since the choice of appropriate packaging materials is just as vital as the packaging method itself, the development of electronic packaging materials has garnered significant attention both domestically and internationally.

Semiconductor packaging technology has evolved rapidly; it took approximately a quarter of a century for plastic packaging to displace the previously dominant ceramic packaging. Today, plastic packaging accounts for over 95% of all packaging (by unit count) due to advantages such as lower costs, simple molding processes suitable for mass production, and reliability comparable to that of metal or ceramic packaging. Plastic packaging is used for nearly 100% of consumer-grade devices and close to 90% of industrial components, whereas ceramic packaging is reserved for a limited number of sectors, such as aerospace and the military. Among plastic packaging materials, epoxy resins are the most widely used, accounting for approximately 90% of the total. Epoxy resins are so vital to the manufacture of electronic devices that it is often said, "Without epoxy resins, there would be no ICs."

Epoxy resins play a crucial role in electronic packaging materials; however, packaging material technology continues to evolve to keep pace with the rapid advancement of semiconductor technology. Currently, the demand for and development of high-performance packaging materials abroad are moving in two directions: (1) developing low-viscosity (or low melt-viscosity) difunctional epoxy resins that allow for high inorganic filler loading, thereby significantly reducing internal stress in packaged devices and mitigating defects such as passivation layer cracking, wiring loosening, and wire breakage; and (2) developing multifunctional epoxy resins incorporating heat- and moisture-resistant structural components, enabling packaged devices to achieve a combination of high heat resistance, low water absorption, and low internal stress.