Samsung's 46 Trillion Won HBM Bet: What Back-End Packaging Is

Samsung Electronics plans to spend 46 trillion won, about $34.6 billion, to turn its Onyang campus in Asan, South Korea, into a hub for high-bandwidth memory, or HBM. The plan calls for five HBM production lines, and the first new building broke ground on November 12, 2026, with operations targeted for June 2028. The short answer: Onyang handles the back-end step of stacking, connecting and testing chips, and for HBM that step is described as a key factor in product competitiveness.

All dollar figures in this post use an exchange rate of 1,330.7 won per U.S. dollar, the Seoul daytime market close on November 12, 2026.

What is HBM, and what does back-end work mean?

Chipmaking is usually split into two halves. The front end etches circuits onto silicon wafers. The back end takes finished chips, cuts them, packages them and tests them before they ship. HBM is built by stacking several DRAM chips on top of one another so data can move between memory and processor much faster. It is described as a core component of AI infrastructure.

Because HBM is a stack rather than a single chip, the quality of the stacking, the connections between layers and the final testing determine how competitive the product is. That is exactly the work Onyang does. The site started operating in late 1991 and has handled chip assembly and testing for more than 30 years. At the groundbreaking ceremony, Chairman Lee Jae-yong said the campus, once focused on simply assembling and testing ordinary chips, would become a cutting-edge HBM hub, calling HBM the heart of AI chips.

Where does the 46 trillion won go?

According to the company figures reported at the ceremony, about 6 trillion won ($4.5 billion) will go to building the plant and about 40 trillion won ($30.1 billion) to advanced equipment, invested in stages rather than all at once.

A simple calculation shows the balance. Equipment is 40 out of 46, or about 87% of the total, while buildings are about 13%. In other words, this is mostly a bet on machines. Dividing the total by five lines gives an average of a little over 9 trillion won per line, but Samsung has not published per-line figures, so that number is only a rough sense of scale.

The new Line 5 will have a cleanroom of about 31,000 square meters across three floors, roughly the size of four soccer fields. Once the work is complete, the campus floor area is expected to grow from 270,000 square meters to 420,000 square meters, about 1.6 times its current size. The company expects about 700 direct jobs once the line runs, with an average of 3,400 workers a day during construction and about 2.6 trillion won ($2.0 billion) in production-inducing effects. Local reports also said Samsung moved the schedule up by a year from its original plan.

The groundbreaking came four months after Samsung presented the investment plan at a regional briefing in July, according to local reports, and President Lee Jae-myung attended the ceremony. Local reports also cited a target of starting volume production in May 2029, about eleven months after the June 2028 start of operations.

How does Onyang fit into Samsung's wider plan?

The Onyang line is part of a larger regional push. Samsung affiliates plan to invest a combined 144 trillion won ($108 billion) in the Chungcheong region, according to local reports: 60 trillion won from Samsung Electronics, 67 trillion won from Samsung Display, 8 trillion won from Samsung Electro-Mechanics and 9 trillion won from Samsung SDI. By that breakdown, the 46 trillion won for Onyang is about 77% of Samsung Electronics' share. The company also plans to expand and modernize HBM-related equipment at its Cheonan site, according to the same reports.

What should readers watch next?

Two conditions matter. First, the money arrives in stages, so the headline figure is a multi-year plan rather than a one-time payment. Second, since equipment makes up most of the budget, real output depends on when the machines are installed and running. The first checkpoint is June 2028, when Line 5 is scheduled to start.

Key terms

- HBM (high-bandwidth memory): memory made by stacking DRAM chips vertically so data moves faster, used in AI systems.

- Back-end process: the stage after chips are made, covering packaging, connection and testing.

- Cleanroom: a dust-controlled production space required for chipmaking.

Bottom line

Samsung's Onyang plan puts 46 trillion won into the part of HBM production that most affects quality, with about 87% of the money going to equipment. Whether Line 5 starts on time in June 2028 will be the first real test of the plan.

Sources: Samsung Electronics (Onyang groundbreaking announcement, as reported); Samsung Semiconductor HBM overview