What SK Siltron CSS does

SK Siltron CSS (legal entity SK siltron css, LLC) is a U.S.-domiciled, vertically integrated manufacturer of silicon carbide (SiC) wafers for next-generation power semiconductors. The company is a wholly-owned subsidiary of SK Siltron, itself part of South Korea's SK Group, and was formed when SK Siltron acquired DuPont's Compound Semiconductor Solutions business in March 2020. Operations are anchored in Michigan — Auburn serves as the primary R&D and process development site, while Bay City houses the large-scale manufacturing facility expanded under a $300 million initial investment and a $544 million U.S. Department of Energy ATVM loan finalized in November 2024. SK Siltron has committed a total of $630 million in capital investments between 2022 and 2027.

The company's two core product lines are SiC substrate wafers (4H n-type, 150mm and 200mm diameters) and SiC epitaxial wafers (150mm and 200mm), produced using proprietary physical vapor transport (PVT) crystal growth and metal-organic chemical vapor deposition (MOCVD) epitaxy. It also manufactures the precursor gases used in epitaxial growth in-house, providing vertical control over quality and cost. Defect densities are reported as low as MPD ≤ 0.1 cm⁻², TSD ≤ 400 cm⁻², and BPD ≤ 1,500 cm⁻². The company holds ISO 9001, ISO 14001, ISO 45001, and IATF 16949 certifications, with a focus on serving automotive-grade supply chains.

SK Siltron CSS generates revenue through direct enterprise sales of SiC wafers to global semiconductor manufacturers and device makers under multi-year supply agreements, with pricing conducted on a quote basis. It explicitly avoids competing with customers by not manufacturing devices. Named anchor customers include Infineon Technologies (long-term 150mm supply with a planned transition to 200mm) and Qorvo (multi-year bare and epitaxial wafer supply). End applications span electric vehicles, renewable energy power conversion, industrial automation, RF/communications, and research. The company achieved an estimated 6% share of the global SiC wafer market in 2023 and has stated the objective of becoming a top-five global SiC producer by the time the Bay City expansion completes in 2027.

Name

SK Siltron CSS

Legal name

SK siltron css, LLC

Website

https://sksiltroncss.com

Company type

Private

Founded year

2020

Operating status

Operating

Headcount range

101–250 employees

Short description

SK Siltron CSS is a U.S.-domiciled, vertically integrated manufacturer of silicon carbide substrate and epitaxial wafers for power electronics, serving global semiconductor manufacturers across automotive, renewable energy, industrial, and RF/communications applications.

Ownership category

akta.pro rank

Product category

Compound Semiconductor Wafers

NAICS

Semiconductor and Other Electronic Component Manufacturing (33441)

SIC

Electronic Components, Nec (3679)

akta.pro primary industry

Compound Semiconductor Wafers & Substrates (SiC/GaN/GaAs/InP/Sapphire) (HDAHAGAB)

Keywords

• Silicon carbide wafers
• Semiconductor materials
• SiC substrates
• Power electronics wafers
• Wafer manufacturing

Headquarters

HQ city

Gyeongju

HQ country

South Korea

HQ region

Asia

Offices8 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Supply Chain, Operations, Personnel, Technology or R&D, Infrastructure

Revenue model

1. SiC Wafer and Substrate Sales: Sale of silicon carbide (SiC) substrate wafers in 150mm and 200mm diameters to semiconductor manufacturers for power electronics applications
2. SiC Epitaxial Wafer Sales: Sale of epitaxially-grown SiC wafers combining 4H single-crystal substrates with epitaxial films for high-performance power device production

Pricing tiers

Go-to-market motion1 record

Distribution channels2 records

Marketing channels5 records

Core offering

SK Siltron CSS manufactures high-quality silicon carbide (SiC) substrate wafers and epitaxial wafers in 150mm and 200mm diameters using proprietary physical vapor transport (PVT) crystal growth and metal-organic chemical vapor deposition (MOCVD) epitaxy processes. The company is a vertically integrated SiC material supplier focused exclusively on providing wafers and substrates to power semiconductor device manufacturers across automotive, renewable energy, industrial, and RF/communications markets.

Product overview

SK Siltron CSS is a vertically integrated SiC material manufacturer providing two core product lines: SiC Substrate/Wafers (available in 150mm and 200mm diameters) and SiC Epitaxial Wafers (available in 150mm and 200mm diameters). The company focuses exclusively on providing wafers and substrates for compound semiconductor applications and does not manufacture devices, allowing them to serve customers without competing with them. Their products are used in power electronics for electric vehicles, renewable energy systems, industrial applications, and RF/communications.

Differentiator

Problem solved

Functional benefit

Products and services

• SiC Substrate/Wafers (150mm, 200mm) High-quality 4H n-type silicon carbide (SiC) wafers available in 150mm and 200mm diameters, produced using proprietary physical vapor transport (PVT) growth techniques and computer-aided manufacturing (CAM) for demanding power electronics applications. Targeted at semiconductor device manufacturers serving automotive, renewable energy, industrial, and RF/communications markets.
• SiC Epitaxial Wafers (150mm, 200mm) Silicon carbide homoepitaxial wafers combining 4H single-crystal, 4-degree off-axis, n-type SiC substrates with epitaxially grown SiC films featuring state-of-the-art thickness and doping uniformity for high-performance power device production. Targeted at semiconductor manufacturers building high-performance power electronics.

Quantifiable outcome

• 7.5% driving range increase for EVs using SiC-based power semiconductors
• +5 more outcomes

Named customers2 records

Segments5 records

Ideal customer profiles4 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature5 records

Partnerships

Two partnerships are on record, tiered core.

• Infineon Technologies AGcoreStrategic or Co-development Partner · 10 January 2024Long-term supply agreement where SK Siltron CSS provides competitive and high-quality 150mm SiC wafers supporting Infineon's SiC semiconductor production. In a subsequent phase, SK Siltron CSS will assist Infineon's transition to 200mm wafer diameter. This partnership expanded SK Siltron CSS's customer base and contributed to achieving 6% global SiC wafer market share in 2023.
• QorvocoreStrategic or Co-development Partner · 2 November 2022Multi-year supply agreement for silicon carbide (SiC) bare and epitaxial wafers between Qorvo, a leading global provider of connectivity and power solutions, and SK Siltron CSS. This was one of SK Siltron CSS's first major long-term supply agreements following rapid market expansion.

Scale indicators15 records

Recent moves9 records

Expansion highlights5 records

Direct peers

• Wolfspeed: Leading US-based pure-play SiC wafer and power device manufacturer. Most directly comparable competitor to SK Siltron CSS given overlapping focus on SiC substrates and epitaxial wafers for power electronics, and the company's previous employment of SK Siltron CSS VP Commercial Edward Chen.
• Coherent Corp (formerly II-VI): Global compound semiconductor materials manufacturer with a sizable SiC substrate business acquired from II-VI. Directly competes with SK Siltron CSS in 150mm and 200mm SiC wafer supply for power electronics and EV applications.
• Resonac (formerly Showa Denko) / SiCrystal: Japanese-headquartered materials company and parent of SiCrystal, one of the largest global SiC wafer suppliers. Directly comparable to SK Siltron CSS in SiC substrate manufacturing and supply agreements with major power semiconductor customers.

Emerging players

• SICC (Shengong Semiconductor): China-based SiC wafer manufacturer rapidly scaling capacity. While primarily serving Chinese customers, SICC represents a meaningful emerging competitor in the global SiC substrate market that could pressure pricing for SK Siltron CSS.
• TankeBlue Semiconductor: Chinese SiC substrate manufacturer developing 150mm and 200mm wafers. Comparable emerging player in the compound semiconductor wafer space, especially relevant given SK Siltron CSS's China sales office and exposure to Chinese demand.

Broad incumbents

• onsemi (ON Semiconductor): Major US-headquartered power semiconductor company that has acquired SiC substrate capability (GTAT) and competes as both a customer of wafer suppliers and an integrated SiC player. Overlapping customer base and competing supply dynamics with SK Siltron CSS.
• STMicroelectronics: European semiconductor leader with significant SiC power device operations and growing in-house wafer sourcing. Broad incumbent in power electronics that overlaps with SK Siltron CSS's customer base in automotive and industrial segments.
• ROHM Semiconductor: Japanese power semiconductor company with internal SiC substrate capability (acquired SiCrystal stake earlier) and a leading position in SiC MOSFETs. Overlaps with SK Siltron CSS in supplying SiC-based power solutions to automotive customers.

Others

• Infineon Technologies: SK Siltron CSS's anchor customer (long-term SiC wafer supply agreement, Jan 2024) and a major global power semiconductor company. Infineon is included as an adjacent ecosystem participant because it is both the largest customer and a potential vertically integrated competitor if it expands captive wafer sourcing.
• SK Siltron (parent company): South Korean parent company of SK Siltron CSS and broader silicon wafer supplier. While a separate entity, it shares the SiC technology roadmap and is the entity being acquired by Doosan Group; relevant for capital allocation and strategic context affecting SK Siltron CSS.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat6 records

Key risks6 records

Key highlights7 records

Customer concentration

• LinkedInlinkedin.com/company/sk-siltron-css

Compliance4 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles5 records

Funding overview

Funding rounds2 records

Investors1 record

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A1 record

Investments1 record

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about SK Siltron CSS