Samsung breaks ground on HBM plant to close gap with SK Hynix

Samsung has broken ground on a new plant for high-bandwidth memory, an expansion the Korea Herald calls a megaproject. The facility is the company's bid to close the gap with SK Hynix, the rival that has led the market for the stacked chips AI accelerators consume in bulk.

High-bandwidth memory stacks DRAM dies vertically and wires them tight against the processor, trading silicon area for bandwidth. It is the format Nvidia's accelerators feed on, and across the supply chain the question of recent years has been less whether demand exists than who gets to serve it. SK Hynix built first and built big; Samsung has been the one chasing in the segment that now carries the prices.

The label matters less than the timing. Memory is a commodity business with a delayed fuse: fabs take years to build, so capacity decisions made at the top of a price cycle arrive in the middle of the next one. The DRAM industry ran this loop through the 1990s, the dot-com bust and the 2019 downturn, and the survivors are the three names building again — Samsung, SK Hynix and Micron.

HBM was supposed to be different. The chips are custom-stacked, qualified with each customer and sold on agreements rather than spot prices, closer to an order book than a commodity ticker. But the customer list is short. Three suppliers building against one buyer's appetite are not so much a market as a queue, and if all three arrive on time, they arrive together.

The buyer has had a week of its own: Nvidia's market value fell by hundreds of billions of dollars, and reports had its board weighing the future of founder Jensen Huang. Every supplier now pouring concrete is doing so against that company's order book.

Groundbreaking ceremonies take a morning. The capacity they announce arrives years later, on roughly the same schedule as everyone else's.