TGV still faces technical barriers; CoPoS commercialization not likely until 2030

DIGITIMES has found that the advanced packaging market continues to expand as demand for AI chips rises and package sizes increase. OSATs and panel makers have been developing FOPLP technology in advance, while wafer fabs are pursuing CoPoS technology. Both aim to replace ABF substrates with glass substrates, or silicon interposers with glass interposers. At present, some OSATs and panel makers have already mass-produced FOPLP, but glass interposers have yet to enter mass production, mainly because through-glass via technology is still immature. Ibiden, a leading substrate supplier in Japan, expects the technology barriers to through-glass vias to be broken only by 2030, meaning advanced CoPoS using glass interposers is also unlikely to be commercialized before then.

As AI chip package areas increase in line with computing power requirements, the number of chips that can be packaged on a 12-inch wafer is falling, raising area waste. Warpage caused by the large mismatch in thermal expansion coefficients between traditional organic substrate materials such as ABF and silicon wafers is also becoming more severe. In addition, interposers, which serve as a bridge between different chips and packaging platforms, require ever larger areas, making it necessary to replace silicon wafers with lower-cost materials. Because of its compatible thermal expansion coefficient, high flatness, low signal loss, and low cost, glass substrate is regarded as the most suitable substitute. As a result, related companies are developing advanced packaging technologies based on glass substrates to meet market demand.