High Bandwidth Memory (HBM) employs a vertical stacking architecture for DRAM chips, which can substantially boost data processing speed and bandwidth. However, the process is complex and carries a high risk of yield loss; low yields drive up production costs. As a sixth-generation product, HBM4 is considerably more challenging to manufacture than its predecessors, and whether yields can be stabilized in the early stages of mass production is one of the key variables determining large-scale production competitiveness. According to industry sources, SK Hynix's HBM4 production yield has risen above 70%, and with the same production input, qualified output has increased by approximately 16.7% compared with a 60% yield. Previously, SK Hynix stated on its third-quarter earnings call that both front-end and back-end process yields for HBM4 were among the industry's best, outperforming the original plan, and the company raised its internal targets. Currently, SK Hynix, Samsung, and Micron are all vying for the HBM4 market, and this yield progress is expected to reshape the industry's competitive landscape, with competition among the three set to further intensify.