SK siltron Brand Guidelines: Gumi’s 1983 Wafer Maker, LG Siltron & a Pending Doosan Sale

A wafer company that changed its name three times.

SK siltron is a maker of silicon wafers, the polished discs on which chips are built, and its home has always been Gumi, the industrial city in North Gyeongsang province. The company says it was established in 1983 and began its semiconductor wafer business in 1984, with 4-, 5- and 6-inch wafers. Korean Wikipedia dates the founding to 25 April 1983 and gives the first company name as Kosil (코실); in 1989, it says, the business was renamed Dongbu Electronics Communications.

The decisive change came in 1990. Korean Wikipedia says Lucky Materials, which in 1984 had signed a technology agreement on silicon wafers with the American company Siltec, took management control of the former Kosil that year, with what it calls Gumi plant 2, and the company was renamed Siltron. In 1991 Siltron took over Lucky Materials’ own wafer business, and in 1992 it set up a research institute. The company’s own history gives 1990 as the year it was renamed Siltron Co., Ltd.

Growth followed the industry’s move to larger wafers. Korean Wikipedia says Siltron bought the Icheon plant of Dongyang Electronic Metals in 1995, and the company still lists an Icheon branch. The company says it began producing 200 mm wafers in 1996 and 300 mm wafers in 2001; Korean Wikipedia dates the first prime ingot from a 200 mm crystal grower of its own design to 2001 and the completion of the 300 mm plant, Gumi plant 3, to 2002. The company says it developed its own single-crystal growing equipment in 2003 and expanded its wafer plant in 2008.

The name changed again in 2011, to LG Siltron, according to Korean Wikipedia. Under that name the company installed 450 mm pilot production lines in 2013, by its own account, and shipped its first 450 mm wafer in 2014, Korean Wikipedia says. It had opened a US subsidiary in 2001 and a Japanese one in 2010.

SK, a national core technology and silicon carbide.

In January 2017 the company changed hands. On 23 January that year SK Holdings, the holding company of the SK group, said its board had decided to buy a 51 percent stake in LG Siltron from LG, The Korea Times reported. The paper noted that SK had taken over Hynix Semiconductor, now SK hynix, in 2011, and quoted an LG official saying the buyer had been chosen partly with the job security of LG Siltron’s employees in mind. The company was renamed SK siltron Co., Ltd. in 2017, its history says. It writes its name with a lower-case “siltron,” and we follow that spelling here.

The company says that in 2019 its “large crystal growing technology” was selected by the Korean government as a national core technology, and on its corporate page it calls its 300 mm ingot growing technology a “national core technology.” Korean Wikipedia records a Shanghai subsidiary set up in 2019.

Its biggest step outside silicon came the next year. On 6 March 2020 Semiconductor Today reported that SK siltron had completed the purchase of the silicon carbide wafer unit of DuPont Electronics & Imaging, based in Delaware. The deal had been decided at a board meeting the previous September and closed on 29 February 2020; the business’s main site is at Auburn, Michigan, about 120 miles north of Detroit. The same report said SK siltron’s US subsidiary had been set up in 2001 and that the company had subsidiaries and offices in the United States, Japan, China, Europe and Taiwan.

The unit now trades as SK siltron css. Its website lists sites in Auburn and Bay City, Michigan, and products in 150 mm and 200 mm: silicon carbide substrates and wafers, and epitaxial wafers. It describes itself as a vertically integrated silicon carbide materials maker and says: “We don’t make devices and we don’t compete with our customers.” The parent’s history lists the unit’s founding and the start of its silicon carbide wafer business in 2020.

The company has since widened its range again. Its history says it began a gallium nitride wafer business in 2022, together with what it calls an EV advanced-materials business, covering nano-carbon heating film and chip bonding, and that a new plant in Gumi was completed in 2025. Evertiq reported in August 2026 that it makes 300 mm and 200 mm silicon wafers.

Design and documentation.

Silicon-wafer and chip-materials makers sell to a small number of very large customers, and their public image is built for engineers, investors and recruits rather than shoppers. Most of what they make never reaches a consumer’s hand: a polished wafer, a bottle of photoresist or a photomask is used up or hidden inside a chip long before anything is sold in a shop.

Their pictures tend to come from the factory floor. Corporate reports and websites in this field favour mirror-polished silicon wafers catching the light of a cleanroom, cylindrical crystal ingots drawn slowly out of a furnace, photolithography bays lit in amber to protect light-sensitive resists, and racks of high-purity chemical bottles. People appear mostly as technicians in full-body cleanroom suits, often called bunny suits, with only their eyes showing.

Names in this group often record a history. Shin-Etsu joins two old Japanese provinces, and SUMCO is an acronym of the company formed by a 1999 merger. The palettes in these guides are our own interpretations, not official colours.

The industry meets at its trade shows. SEMICON West in the United States, SEMICON Taiwan in Taipei and SEMICON Japan in Tokyo bring wafer, chemical and equipment suppliers onto the same floor as chipmakers, and booths there show the same vocabulary of wafers, ingots and cleanroom imagery. This guide sets out what can be checked about each company — who founded it, who owns it, where it makes its products — and marks clearly what rests only on the company’s own word.

A pending change of owner.

SK siltron’s ownership is changing again. On 17 December 2025, Korean Wikipedia says, citing the Maeil Business Newspaper, SK named the Doosan group as preferred bidder for its stake. On 31 July 2026 SK Inc. signed an agreement to sell its 70.6 percent stake in SK siltron to Doosan, The Korea Times reported, citing a regulatory filing; the paper described SK siltron as the country’s sole dedicated producer of semiconductor wafers and said SK had put it up for sale as part of a restructuring. On 21 August 2026 the law firm Dechert, which advised SK, said the parties expected the deal to close on or before the end of January 2027, subject to regulatory approvals and other conditions. The sale was agreed in July 2026 and was not completed at the time of writing; Doosan said SK siltron would not be listed, Evertiq reported on 26 August 2026.

Until then the company presents itself as part of the SK group. Its corporate pages carry the group’s management system, SKMS, which it says was first set down in 1979, and its “Happy Management” philosophy, and it says it is working towards the Net Zero 2040 target set by the SK group, by improving process efficiency and using more renewable energy. It calls itself “the only semiconductor wafer manufacturer in Korea” and describes its core business as wafers for next-generation chips customised to individual customers; it names the steps of growing, shaping, polishing and cleaning as the parts of its process it aims to improve. It offers a downloadable corporate identity file on its website, and its silicon carbide unit runs a separate site under the SK siltron css name.

For a design guide, SK siltron shows how a company can keep one product and one city while its name follows its owners, from Siltron to LG Siltron to SK siltron. Compare GlobalWafers, another wafer maker built partly through acquisitions, and SUMCO, a Japanese wafer maker formed from two silicon businesses. For this guide we use a slate, a wafer silver and an orange-red with a sans, an unofficial interpretation; no product or logo is reproduced.

Keep SK siltron’s identity on hand — save it to a board in the Made Good inspiration library.