TSMC nears limits of AI chip packaging capacity after years of doubling

TSMC has pursued an aggressive capacity expansion strategy for its CoWoS and SoIC advanced packaging lines, the technologies used to stack and interconnect chips for high-performance AI processors. Over the past several years, the company has roughly doubled capacity in these segments annually, a cadence that reflects the intensity of demand from major AI chip customers. The manufacturing process has matured significantly: TSMC is now operating CoWoS at yields better than 98%, and on some products reaching 99%, across multiple customers already running high-volume production. These yield levels indicate that the manufacturing process has reached a plateau of efficiency where most wafers are being converted to usable product. As TSMC nears these physical and operational limits—doubling capacity every year becomes mathematically harder at larger scales, and yields cannot sustainably exceed 100%—the company faces a fundamental challenge: continuing to meet AI demand growth may require not just more capacity, but fundamentally new packaging architectures or manufacturing approaches. The current trajectory suggests TSMC's annual doubling era may be ending, with implications for how the broader AI chip supply chain can continue to expand.