Onsemi is staking its life on securing leadership in the SiC power semiconductor market by expanding its SiC wafer capacity to up to 1 million sheets. With the completion of the Bucheon S5 line, expectations are rising as to whether Onsemi, which currently holds the second largest market share in the SiC market, will be able to take another leap forward.

Intelligent power and sensing company Onsemi held a completion ceremony on the 24th to commemorate the completion of the world's largest, most advanced silicon carbide (SiC) manufacturing facility in Bucheon, Gyeonggi Province.

Onsemi’s Bucheon Fab S5 line has a production capacity of more than 1 million 8-inch (200mm) SiC wafers per year when in full operation. To enhance its SiC manufacturing capacity, Onsemi plans to hire up to 1,000 domestic employees over the next three years, mostly in highly technical positions. This is an increase of more than 40% from the current workforce of approximately 2,300.

SiC devices are essential components for power conversion in electric vehicles (EVs), energy infrastructure, and high-power EV chargers, and demand has been rapidly increasing recently. SiC chips produced by Onsemi in Korea are supplied to the entire world, including Korea, Asia-Pacific, the United States, and Europe.

Onsemi said it is currently experiencing a surge in demand and expects demand to exceed supply for the foreseeable future. Onsemi said the expansion of its Bucheon fab will address the urgent need for additional production capacity, ensuring continued supply to customers and focusing on strengthening its leadership in intelligent power solutions.

“Our 6-8-inch SiC wafer fab in Bucheon is critical to the continued success of our fully integrated SiC supply chain,” said Hassane El-Khoury, CEO of ONSemi, in his opening remarks at the inauguration ceremony. “By expanding our infrastructure to meet the growing demand for SiC, we are supporting the acceleration of global energy infrastructure and vehicle electrification.”

■ Targeting 40% of global production, preparing for 8-inch conversion
Onsemi held a press conference on this day, and CEO Hassan El Khoury and Vice President of Power Solutions Group Simon Keaton attended and answered questions.

Hassan El Khoury, CEO, said that when the Bucheon S5 line ramps up and all manufacturing facilities in the fab are operating at full capacity, they expect to see a tenfold increase in production compared to before. Onsemi's Bucheon fab is the company's sole SiC production facility, and is targeting to account for 40% of its total global production, it explained.

In this way, Onsemi's Bucheon fab has the status of Onsemi's most important production facility, and Onsemi is reported to be supplying and cooperating with SiC devices to global automobile OEMs such as Tesla, Hyundai, Kia, BMW, and Nio.

It is known that this S5 line expansion is an expansion to meet rapidly increasing customer demand, and that the company has been investing in increasing production capacity in the automotive and industrial sectors since 2021 through strategic decision-making focused on the sector. “We will accelerate our journey to create a sustainable ecosystem in the industrial and automotive sectors,” said CEO Hassan. “We will continue to pursue this over the next five years and expand our investment in this area.”
When asked about the transition from 6-inch to 8-inch wafers, Vice President Simon Keaton responded, “We are already in the process of manufacturing 8-inch engineering wafers,” and “Currently, we are focusing on 6-inch production because the overall market demand is much higher for 6-inch products, but we also have the ability to easily transition to 8-inch within two years.”

■ 1 year and 4 months of construction period, installation of ASML, Applied, etc. facilities
The Onsemi S5 line is a manufacturing facility dedicated to SiC, consisting of two buildings: one factory building and one utility building. The facility, which has one underground floor and six above-ground floors, is comprised of five floors in total, including two floors specialized for the ion implantation process, reflecting a design to improve production line efficiency.

An automatic return device was installed to connect all existing production lines S1 to 4, integrating the entire SiC line within the Bucheon facility into one to improve efficiency.

Although the construction period was 1 year and 4 months, it is said that the planning stage and investment approval were a long journey. Onsemi said that after starting the first SiC production at the Bucheon fab in 2016, it began full-scale SiC mass production in 2018 and reviewed expansion within the existing site to expand the production line.

It is said that the expansion of semiconductor factories in the metropolitan area was difficult due to various regulations and foreign investment restrictions. However, thanks to the local government and the government's K-semiconductor policy keynote, Onsemi received approval for its headquarters investment in 2021, and began establishing a basic plan and construction plan in 2022. After receiving approval, construction began in June of last year and was completed on September 30 of this year.

For the S5 line expansion, ASML, Applied Materials, Tokyo Electron, Disco, Yullim Construction, PJP Tech, Lead Engineering, KLA, Exitron Korea, Air Test System, P-Sem, CNDPLUS, Join Technology, Innomax, Ilwoo ING, and Dansung participated in setting up, coordinating, and constructing semiconductor facilities and equipment.

Kang Byeong-gon, CEO of Onsemi Korea, said, “Building a manufacturing facility on an existing site is a more complex and difficult task than building a new site,” and expressed his gratitude to the construction and facility companies that participated in the expansion process, saying, “By introducing new construction methods, we were able to shorten the construction period, increase structural strength, and even reduce costs.”