Rohm Achieves Green Innovation Fund Project's Technical Goals Two Years Ahead of Schedule

　In the Green Innovation Fund Project "Building Next-Generation Digital Infrastructure" project ("Next-Generation Power Semiconductor Device Manufacturing Technology Development (Subsidy Project)") implemented by NEDO, Rohm Co., Ltd. has achieved its technical goals for "Development of 8-inch Next-Generation SiC MOSFETs" two years ahead of the original schedule.

　Rohm established epitaxial growth technology and low on-resistance technology compatible with 8-inch SiC wafers, and constructed an 8-inch SiC device manufacturing line integrating these elemental technologies. As a result, the project's technical goals of "reducing power loss by 50% or more in power converters, etc." and "cost reduction" were achieved.

　Under the framework of this project, NEDO and Rohm have accurately grasped global market trends surrounding power semiconductors and promoted this project with a view to early social implementation, from the research and development stage.

　Particularly for SiC power semiconductors, with global demand expected to expand in the future, the strong recognition of the need to establish competitive technologies early, with an eye on the market, and the proactive promotion of research and development, led to the early achievement of the technical goals.

1. Background

　NEDO is promoting the "Building Next-Generation Digital Infrastructure" project as part of the Green Innovation Fund Project, aiming to realize next-generation green power semiconductors and next-generation green data centers.

　This project targets fields where innovative energy saving is required for the realization of carbon neutrality, such as electric vehicles (xEV*1), renewable energy, and server power supplies. It aims to improve the performance and efficiency of next-generation power semiconductors (SiC, GaN), reduce power loss in converters by 50% or more, achieve cost reduction equivalent to Si power semiconductors, and further promote early widespread adoption.

　Rohm started this project*4 in April 2022, focusing on "Development of 8-inch Next-Generation SiC*2 MOSFET*3" as one of the core themes of the "Next-Generation Power Semiconductor Device Manufacturing Technology Development" project, and has now achieved its technical goals two years ahead of schedule. This project will conclude in fiscal year 2025, aiming for even earlier social implementation.

2. Achievements

(1) Construction of an 8-inch SiC device manufacturing line

　In this project, Rohm achieved cost reduction through larger diameter 8-inch SiC wafers and process optimization, despite SiC requiring higher temperature processes and being more difficult to manufacture compared to Si. Concurrently, epitaxial growth*5 technology and low on-resistance technology compatible with 8-inch wafers were established. Furthermore, by overcoming various technical challenges associated with 8-inch wafers and the highly difficult processes unique to SiC, and integrating these elemental technologies, an 8-inch SiC device manufacturing line (hereinafter, "this line") was constructed in a dedicated building at Rohm Device Manufacturing Chikugo Plant.

(2) Performance verification of 8-inch SiC devices

　The 8-inch SiC MOSFET devices manufactured on this line were mounted in Rohm's in-house modules, and a comparative evaluation of power loss was conducted under operating conditions based on the assumed actual usage conditions of inverters. As a result, it was confirmed that power loss in power converters could be reduced by 50% or more compared to conventional Si IGBT*6 devices, demonstrating the target performance.

　Towards stable supply to support widespread adoption, continuous efforts have been made to improve challenges across the entire 8-inch SiC manufacturing process and ensure the stability and reliability required for social implementation. Through these efforts, Rohm has established a production base for 8-inch SiC power semiconductors and built a supply system. We will continue to strengthen our supply system to meet expanding demand.

3. Future Plans

　Rohm will continue research and development for further cost reduction and power loss reduction based on 8-inch SiC technology, anticipating the global expansion of power semiconductor demand.

　NEDO will accelerate social implementation towards the realization of carbon neutrality by 2050 and contribute to greenhouse gas emission reduction through the widespread adoption of next-generation green power semiconductors.

【Notes】

*1 xEV

This is a collective term for electrified vehicles such as Battery EV (BEV), Hybrid Electric Vehicle (HEV), Plug-in Hybrid (Electric) Vehicle (PHEV/PHV), and (Hydrogen) Fuel Cell Electric Vehicle (FCEV/FCV).

*2 SiC

Silicon Carbide (a compound of carbon (C) and silicon (Si)).

*3 MOSFET

Metal Oxide Semiconductor Field Effect Transistor.

*4 This project

Project name: Green Innovation Fund Project / Building Next-Generation Digital Infrastructure / Next-Generation Power Semiconductor Device Manufacturing Technology Development / Development of 8-inch Next-Generation SiC MOSFETs

Project period: FY2022 - FY2025

Project overview: Green Innovation Fund Project / Building Next-Generation Digital Infrastructure project

NEDO Green Innovation Fund Project Special Site https://green-innovation.nedo.go.jp/

Building Next-Generation Digital Infrastructure

https://green-innovation.nedo.go.jp/project/building-next-generation-digital-infrastructure/

Rohm News Release Site

https://www.rohm.co.jp/news-detail?news-title=2026-04-02_news&defaultGroupId=false

*5 Epitaxial growth

This refers to thin-film crystal growth, where new crystals are grown on a substrate crystal. It enables the creation of high-quality semiconductor thin films with few defects.

*6 IGBT

Insulated Gate Bipolar Transistor.