SK Hynix’s $720 Billion AI Memory Ambition

In South Korea, where challenging mountainous terrain makes ambitious construction projects a formidable task, the world’s leading high-bandwidth memory manufacturer is embarking on a monumental investment of $720 billion. This colossal sum is earmarked for what the company asserts will become the most extensive network of memory fabrication plants globally.

SK Hynix, a titan in the semiconductor industry whose market capitalization has surged more than fivefold over the past year to exceed $1 trillion, is making a significant strategic wager on the enduring and escalating demand driven by artificial intelligence. The current landscape, characterized by soaring prices and acute capacity constraints, is fundamentally reshaping the historically cyclical boom-and-bust nature of the memory chip market. Leading AI chip designers, such as Nvidia, are increasingly willing to absorb greater supply chain risks as they urgently seek to secure essential memory components.

The high-bandwidth memory (HBM) market is notably concentrated, with a handful of key players dominating production. In the first quarter, SK Hynix commanded an impressive 58% share of the HBM market. Trailing closely behind were fellow South Korean powerhouse Samsung and U.S.-based Micron, each holding a 21% market share, according to data from Counterpoint Research. This consolidation underscores the strategic importance and competitive intensity within this critical segment of the semiconductor industry.

To finance its ambitious expansion strategy, SK Hynix, listed on the Korea Exchange, successfully raised $26.5 billion in July through a landmark listing of its shares on the Nasdaq. This capital infusion marked the largest sum ever raised by a foreign company through a U.S. market listing, highlighting global investor confidence in the company’s growth trajectory.

However, recent performance has presented a challenging period for new investors. Since reaching a peak of nearly $195 on July 14th, the U.S.-listed shares have experienced a decline of approximately 21%, closing the previous Wednesday at $154.41. This dip has coincided with broader market volatility in the artificial intelligence sector, particularly impacting chip stocks, and a downturn in the Korean stock market, which derives a substantial portion of its valuation from companies like SK Hynix and Samsung.

Despite these market fluctuations, SK Hynix remains steadfast in its commitment to its historic expansion plans. This initiative is integral to a broader national strategy unveiled in June by South Korean President Lee Jae Myung, aiming to double the country’s memory production capacity within five years. This ambitious national project also includes the development of multiple new mega-fabrication facilities by Samsung.

CNBC was granted exclusive, behind-the-scenes access to SK Hynix’s expansion efforts last month. This included the inaugural on-camera tour of the Yongin Cluster, along with an inside perspective on the sophisticated memory cleanrooms in Cheongju, where the company is also undertaking significant infrastructure upgrades.

A striking architectural distinction between U.S. chip fabrication plants and the three SK Hynix facilities visited in South Korea is their verticality. The initial fabrication building at the Yongin Cluster, with walls constructed only halfway up its towering framework, is projected by SK Hynix to reach the height of a 50-story apartment complex. This structure will house six cleanrooms spread across multiple floors, contrasting with the more sprawling, single-level designs of new fabs in Arizona operated by industry leaders like Taiwan Semiconductor Manufacturing Co. and Intel.

High-bandwidth memory (HBM) is constructed by vertically stacking general-purpose dynamic random-access memory (DRAM) modules. This intricate architecture enables exceptionally rapid data access, a critical requirement for AI processors to execute complex tasks efficiently. The substantial DRAM density inherent in these HBM stacks is significantly impacting the global supply for consumer electronics, as major AI companies are increasingly entering into multi-year contracts that extend far beyond the traditional short-term agreements previously associated with what was largely considered a low-margin commodity product.

“It’s like a war,” remarked Chey Tae-won, chairman of SK Group, the controlling entity of SK Hynix, during an interview in Seoul. “Everybody wants to buy the memory chips. Without that, they cannot produce their AI computing and AI chips.”

Tae-won acknowledged that “prices went up too fast” and expressed his hope that the extensive buildout will help to stabilize the market. “I’m trying to do my best,” he stated.

In July, SK Hynix announced the signing of ten long-term supply agreements with major clients. Notably, Nvidia has secured a stable supply of HBM and committed to co-developing next-generation memory as part of a significant $500 billion deal with SK Group. This partnership also encompasses the development of new data centers in conjunction with SK Telecom, slated for completion by 2027.

Tae-won shared a personal anecdote, showing CNBC a wafer bearing a handwritten message from Nvidia CEO Jensen Huang that simply read, “Please make more.” He also indicated that he engages in regular discussions with prominent industry leaders, including Microsoft’s Satya Nadella, Google’s Sundar Pichai, and Meta’s Mark Zuckerberg. Jensen Huang and AMD CEO Lisa Su have both visited South Korea in recent months for crucial discussions pertaining to memory supply and development.

MS Hwang, research director at Counterpoint Research, observed that hotels in the vicinity of SK Hynix and Samsung’s memory fab expansion sites are consistently fully booked. He noted, “If you name any company in Big Tech, they are all in Korea to sign a contract.”

SK Hynix also operates three memory chip fabrication facilities in China. However, due to U.S. export controls, the company is prohibited from supplying its advanced HBM products to the Chinese market. China is actively developing its own domestic capabilities in advanced AI memory solutions, with companies like CXMT recently making a notable debut in the Shanghai market.

“It’s a race, and now the counterparty of the race is China,” Hwang stated. “That’s going to be a lot more dangerous than anything else in the world.”

President Lee is actively urging accelerated progress on fab construction within South Korea, while the United States is also intensifying its efforts to expand its domestic chip manufacturing capacity.

Micron Technology is investing $50 billion to establish two substantial new memory fabrication plants in Boise, Idaho, with the first facility projected to commence wafer production in 2027. Furthermore, in Clay, New York, the company is developing a $100 billion campus that could potentially house up to four fabrication plants.

SK Hynix is also in the process of constructing its inaugural U.S. facility, with completion anticipated in 2028. This $4 billion fabrication plant in West Lafayette, Indiana, will focus on advanced packaging processes—where memory chips are meticulously stacked and interconnected—rather than front-end wafer manufacturing.

In addition to its planned Indiana operations, SK Hynix maintains a significant U.S. presence. In 2020, the company finalized the acquisition of Intel’s NAND memory business for $9 billion, subsequently establishing the subsidiary Solidigm, which is headquartered near Sacramento, California. In January of the current year, SK Hynix restructured this business segment and launched a $10 billion “AI Company” initiative in the U.S., though this venture does not involve front-end manufacturing capabilities.

Regarding potential new U.S. chip fabrication sites, Tae-won indicated that SK Hynix has been actively evaluating prospective locations for over a month. He commented, “I’m willing to do it, but the problem is that I really have to find the right place.”

Tae-won further elaborated that the memory market is currently at a “turning point,” with the next significant technological advancement focused on custom HBM solutions. This innovation is expected to provide a strategic safeguard for SK Hynix’s substantial investment by mitigating future market risks.

The trend towards custom HBM, which is co-designed in tandem with AI processors, is accelerating with the development of next-generation HBM5. “Nvidia wants their own custom chips and Google wants their own customized HBM, so it’s not just a commodity,” Tae-won explained. “It actually changes the memory chip’s status.”