# East Asia accelerates 8-inch silicon carbide capacity race as power chip makers scale output

*Fabricators across Japan, China, and South Korea add 200mm SiC substrate and epi lines to lower automotive inverter costs.*

**Published:** August 28, 2026  
**By:** Mina Okoro  
**Section:** Analysis & Comparison — Cross-border  
**Format:** Asia Compare  

**Source:** https://eastasiabrief.com/analysis/east-asia-accelerates-8-inch-silicon-carbide-capacity-race-35  
**Publisher:** East Asia Brief (https://eastasiabrief.com/)

---

![Technicians in cleanroom suits inspect a semiconductor sample near industrial furnaces inside a manufacturing facility. (AI-generated image)](https://eastasiabrief.com/media/2026-08-28-9c116fd6b527.png)
*Technicians in cleanroom suits inspect a semiconductor sample near industrial furnaces inside a manufacturing facility. (AI-generated image)*

Power semiconductor manufacturers across Japan, China, and South Korea have expanded commercial manufacturing runs on eight-inch (200mm) silicon carbide (SiC) substrate and epitaxial wafer processing lines, altering the unit cost economics of high-voltage automotive inverters and industrial grid equipment. The industrial shift away from legacy six-inch (150mm) crystal platforms centers on raw material utilization, where the larger diameter yields approximately 1.8 to 1.9 times more usable die per wafer while cutting edge-loss ratios during automated device fabrication. This transition establishes divergent supply dynamics across East Asia, dividing the sector between Japanese material specialists defending high-yield automotive baselines, Chinese integrated producers scaling volume via state-backed capital expenditure, and South Korean conglomerates targeting vertically integrated battery-electric vehicle platforms.

Silicon carbide substrates serve as the wide-bandgap foundational material for power MOSFETs and diodes operating at 800 volts and above, where thermal conductivity and switching efficiency exceed conventional silicon insulated-gate bipolar transistors (IGBTs). Producing single-crystal SiC boules requires physical vapor transport (PVT) or high-temperature chemical vapor deposition (HTCVD) processes operating at temperatures above 2,200 degrees Celsius, conditions that slow boule growth rates to millimeters per hour compared to meters per day for silicon ingots. Expanding boule diameters to eight inches introduces severe thermal gradient stresses that elevate defect densities, specifically micropipes, threading screw dislocations, and basal plane dislocations that propagate directly into epitaxial active layers and degrade device breakdown voltages.

In Japan, power device makers and substrate suppliers maintain capital expenditure allocations aimed at preserving defect-density advantages over regional rivals while converting internal wafer fabs to 200mm architectures. Rohm Co. has directed capital investments into its subsidiary SiCrystal and its domestic production base at the Miyazaki plant, securing a multi-stage manufacturing pathway designed to lift internal eight-inch substrate self-sufficiency toward 100 percent. Rohm operates an integrated model that pairs substrate growth with internal device slicing, polishing, and cleanroom front-end processing for automotive tier-1 buyers. Mitsubishi Electric Corporation is executing an investment program valued at approximately 100 billion yen ($690 million) to construct an eight-inch SiC wafer fab in Kikuchi, Kumamoto Prefecture, structured to start volume manufacturing for traction inverter modules. Resonac Holdings Corporation has scaled commercial shipments of eight-inch SiC epitaxial wafers to third-party device manufacturers, deploying continuous chemical mechanical planarization (CMP) lines and multi-wafer epitaxial reactors to stabilize wafer bow and thickness uniformity across larger wafer surfaces.

China's semiconductor materials industry has pursued rapid horizontal capacity expansion across both substrate synthesis and contract device fabrication, supported by regional industrial subsidies and domestic automotive procurement mandates. Sanan Optoelectronics Co., through its subsidiary Hunan Sanan Semiconductor, has deployed vertically integrated boule growth, substrate slicing, and epitaxial processing lines while constructing an eight-inch SiC fabrication joint venture with STMicroelectronics in Chongqing, projected to reach a capacity of 10,000 eight-inch wafer starts per week at full ramp. SICC Co. has scaled production across its Jinan and Shanghai Lingang facilities, expanding 200mm conductive substrate shipments to European and North American power chip vendors seeking diversified raw material sources. TankeBlue Semiconductor Co. has added PVT furnace capacity across its Beijing and Baoding sites, transitioning from research-grade boule growth to high-throughput commercial runs. These capacity additions have introduced downward pricing pressure on standard six-inch substrates within the domestic Chinese market, forcing producers to migrate capital to eight-inch lines to protect operating margins.

South Korea's SiC supply chain centers on domestic conglomerate integration designed to supply traction inverters for Hyundai Motor Group and regional energy storage system builders. SK siltron Co. has committed capital to its Gumi production base and its US-based Auburn and Bay City facilities in Michigan, operating parallel crystal growth lines to supply automotive-qualified eight-inch conductive wafers. The company combines crystal synthesis with advanced laser-assisted wafer slicing technologies to reduce kerf loss during the ingot separation process, directly addressing the physical yield penalties associated with brittle SiC materials. Foundry operator DB Hitek Co. has completed pilot-line installations for eight-inch SiC power device processing at its fab sites in Bucheon and Eumseong, targeting open-foundry power management and MOSFET manufacturing services for fabless design firms across Asia.

The economic viability of eight-inch lines depends entirely on line yields across boule growth, multi-wire diamond slicing, chemical-mechanical polishing, and epitaxial deposition. While an eight-inch wafer provides nearly double the active surface area of a six-inch wafer, the cost of raw eight-inch substrates remains more than double that of mature six-inch units due to lower boule growth heights and higher crystal breakage rates during slicing. Japanese suppliers lead the sector in defect containment, keeping basal plane dislocation counts below critical automotive thresholds, which supports high chip yields during die passivation and metal interconnect steps. Chinese manufacturers have lowered crystal growth equipment costs by procuring domestic furnace systems from builders like CETC and NAURA Technology Group, reducing initial facility capital intensity but facing steeper learning curves in wafer flatness and epitaxial carrier lifetime stability.

For procurement executives at automotive tier-1 suppliers, the regional divergence across East Asia creates distinct sourcing channels based on system voltage requirements and qualification cycles. Tier-1 automotive systems requiring AEC-Q101 certification and zero-defect performance over 15-year operational lifespans continue to pull high-grade eight-inch material from Japanese and South Korean suppliers with documented automotive traceability. Conversely, commercial power supply systems, photovoltaic string inverters, and domestic Chinese electric vehicle platforms are absorbing increasing volumes of locally sourced Chinese SiC material, driving a two-tier pricing structure across global power semiconductor markets.

Delivery timelines and capital deployment schedules confirm that commercial eight-inch substrate supply will expand through the end of 2026. Mitsubishi Electric's Kumamoto facility, Sanan's Chongqing joint-venture line, and SK siltron's expanded Gumi packaging units have scheduled secondary equipment delivery and pilot batch verification cycles to align with the mass production schedules of next-generation 800V automotive platform architectures.

## Impact map

| Event | Korea | China | Japan | Global impact |
| --- | --- | --- | --- | --- |
| 8-inch SiC capacity ramp | SK siltron/DB Hitek scale 200mm lines | Sanan & SICC expand domestic volume | Rohm & Mitsubishi qualify auto lines | traction inverter costs decline |

## In this story

- **Companies:** Rohm, Mitsubishi Electric, Resonac Holdings, Sanan Optoelectronics, SICC, SK siltron, DB Hitek
- **Tickers:** 6963.T, 6503.T, 4004.T, 600703.SS, 688234.SH, 000990.KS
- **Exposed:** STMicroelectronics, Denso, Hyundai Motor Group, NAURA Technology Group
- **Policy:** Subsidies, Economic Security
- **Impact:** Capex, Supply Chain, Pricing, Cost Structure

---

Cite as: East Asia Brief, "East Asia accelerates 8-inch silicon carbide capacity race as power chip makers scale output," August 28, 2026. https://eastasiabrief.com/analysis/east-asia-accelerates-8-inch-silicon-carbide-capacity-race-35