[Edaily Reporter Choi Oh-hyun ] A “semiconductor stock” frenzy swept through the stock market in the first half of this year. If you had held shares of SamsungElectronics and SK hynix 10 years ago, what would your return be today?

On September 23, 2016, SamsungElectronics’ closing price was 1,571,000 won. Adjusting for the 50-to-1 stock split implemented in 2018, this equates to approximately 30,000 won. Exactly 10 years later, on the 23rd, the closing price stood at 285,500 won—an increase of about 809%. During the same period, SK hynix’s stock price jumped from 39,350 won to 1,862,000 won, representing a return of approximately 4,632%.

Behind this staggering rise in stock prices lies the full 10-year history of the Korean semiconductor industry. As recently as 2016, the memory market was centered on PCs and smartphones. DRAM for PCs, mobile DRAM for smartphones, and NAND flash for data storage were the key drivers of both companies’ earnings. They were directly affected by the typical “memory cycle,” where earnings soared when memory prices rose and plummeted when prices fell due to oversupply.

At that time, SamsungElectronics was the first in the world to mass-produce the first-generation (1x) 10-nanometer-class 8Gb DDR4 DRAM, and V-NAND was transitioning from 48 layers to 64 layers. SK hynix expanded production of its 20-nanometer-class third-generation (2Znm) DRAM while beginning to supply 36-layer 3D NAND, and in November of that year, it began mass production of 48-layer products. In 2016, SamsungElectronics recorded revenue of 51.16 trillion won and operating profit of 13.6 trillion won in its semiconductor business. Its operating profit margin was 26.6%. SK hynix posted lower revenue of 17.198 trillion won and operating profit of 3.2767 trillion won, resulting in an operating profit margin of 19.1%.

Exactly 10 years later, the market had undergone a rapid transformation centered on artificial intelligence (AI) data centers. High-Bandwidth Memory (HBM)—which stacks multiple DRAM chips vertically to increase bandwidth—emerged as a key component determining the performance of AI accelerators. As generative AI spread, demand for HBM used in AI accelerators, such as those from NVIDIA, exploded, establishing memory as a core component that determines AI computing performance, moving beyond its role as a simple storage device.

Technology has evolved significantly. Currently, SamsungElectronics and SK hynix are both expanding their production of 10-nanometer-class 6th-generation (1c) DRAM processes as their mainstay. In NAND, SamsungElectronics is mass-producing 286-layer 9th-generation V-NAND, while SK hynix is mass-producing 321-layer products, raising the number of layers from 48 to 64 a decade ago to around 300. In the HBM sector, both companies have entered the mass production and supply phase for HBM4 this year. While SK hynix currently leads the overall HBM market, SamsungElectronics is rapidly catching up in the HBM4 segment. For the next-generation HBM4E, both companies have completed sample deliveries to major customers and are preparing for mass production.

HBM has also narrowed the earnings gap between the two companies. SK hynix has emerged as the biggest beneficiary of the AI memory boom by securing a dominant position in the HBM3 and HBM3E markets. In the first half of this year, it achieved record-breaking results with revenue of 131.895 trillion won and operating profit of 98.1529 trillion won, resulting in an operating profit margin of 74.4%. SamsungElectronics’ Device Solutions (DS) division also posted revenue of 209.2 trillion won and operating profit of 142.9 trillion won during the same period, with an operating profit margin of 68.3%. Amid the AI memory boom, the performance levels of these two companies have shifted to such an extent that they are now incomparable to their 2016 figures.

The cash generated by the AI boom is being returned to shareholders. Last month, SamsungElectronics’ board of directors approved a plan to implement the company’s largest-ever shareholder return program this year, totaling approximately 90 trillion to 110 trillion won. This amount is roughly five times the previous record of 20.3 trillion won set in 2020. SK hynix also held a board meeting last month and decided to repurchase 40 trillion won worth of its own shares and cancel them in their entirety. The company also established a policy to return more than 50% of its cumulative free cash flow (FCF) from 2025 to 2027 to shareholders.

Just as PCs and smartphones reshaped the value of the Korean semiconductor industry over the past decade, AI is expected to define its value over the next decade. Beyond HBM, technological competition for leadership in the AI era—spanning next-generation memory, foundry services, and advanced packaging—is expected to intensify further.

SamsungElectronics announced that, in the short term, it will expand sales of HBM4, HBM4E, DDR5, SOCAMM2, and enterprise SSDs, while in the foundry business, it will begin mass production of second-generation 2-nanometer mobile products and work to secure more orders for AI and high-performance computing (HPC). The company also announced plans to invest approximately 2,450 trillion won in South Korea by 2040, with about 2,100 trillion won of that amount earmarked for expanding semiconductor production capacity.

SK hynix will also invest approximately 1,100 trillion won by 2040 to proactively address global AI memory demand. In the short term, the company plans to expand HBM4 production and continue developing HBM4E, while increasing the proportion of 1c DRAM and 321-layer NAND and expanding long-term supply agreements (LTAs) to solidify its foundation for mid- to long-term growth.