← Doing Business in Japan’s Semiconductor Industry

Geography is strategy here

Japan’s semiconductor industry is not evenly distributed. It is clustered, and the clusters have distinct characters — different specialisations, different labour markets, different levels of government engagement, and very different risk profiles.

For a foreign company, this matters practically. Where you site an office determines which customers you can serve responsively. Which cluster your acquisition target sits in determines your talent pool. And, as July 2026 demonstrated, cluster concentration determines your exposure to a single seismic event.

Kyushu — “Silicon Island,” and Japan’s centre of gravity

Kumamoto is now the most important semiconductor location in Japan. JASM’s fabs sit in Kikuyo, with Sony Semiconductor Manufacturing’s Kumamoto Technology Center adjacent, Renesas operating wafer fabrication at Kawashiri and assembly/test at Nishiki, and Tokyo Electron Kyushu in Koshi and Ozu. Around them has grown a dense supplier layer — materials, gases, precision parts, chemical handling, construction and facilities services.

Elsewhere in Kyushu: Sony has technology centres in Nagasaki, Oita and Kagoshima; Fukuoka serves as the regional business and talent hub; Oita hosts additional device and materials operations.

The concentration is genuinely remarkable. It is also the region’s principal vulnerability.

The July 2026 earthquake. A magnitude 7.1 event struck Kumamoto on 28 July 2026, registering the maximum shindo 7 on the Japanese intensity scale. Fabs across the region halted. Recovery was, by historical standards, fast: Renesas restarted its Nishiki assembly and test site within roughly a day and began phased restart at Kawashiri in early August; Tokyo Electron resumed Kumamoto operations on 3 August after inspections found no major damage; Sony began staged resumption on 4 August and targeted pre-earthquake output by mid-August; TSMC announced JASM had been fully restored as of 4 August.

The contrast with 2016 — when the same Sony site required months to recover — reflects seismic reinforcement undertaken in the interim. The episode nonetheless made the structural point clearly: a single regional event can simultaneously affect leading and mature-node capacity, image sensors, automotive microcontrollers and equipment production.

If you are siting in Kyushu: proximity to JASM is commercially valuable and increasingly crowded. Land, labour, water and logistics capacity are all under pressure. Business continuity planning is not a formality.

Hokkaido — the newest cluster

Chitose is being built essentially from nothing around Rapidus’s IIM-1 facility, with the Rapidus Chiplet Solutions packaging R&D site nearby within Seiko Epson’s Chitose plant.

Hokkaido offers genuine advantages: available land, cool climate (relevant for both fab cooling and data-centre co-location), abundant water, and renewable-energy potential. It also has a thin industrial base and a limited pool of experienced semiconductor engineers, which is the binding constraint.

For foreign companies: this is the greenfield opportunity in Japan. Supplier positions around Chitose are still being established, and the government is actively courting foreign participation. The risk is straightforward — the cluster’s viability is tied to Rapidus reaching production.

Tohoku — the quiet base

Northeastern Japan hosts long-established device and materials operations: Kioxia’s Kitakami operation in Iwate, Tokyo Electron’s Miyagi facilities, Sony’s Miyagi site, and a substantial materials and components base across Yamagata and Fukushima.

Tohoku is less discussed than Kyushu or Hokkaido, which makes it undervalued in most foreign analyses. Land and labour costs are moderate, and there is an experienced workforce. Seismic exposure is significant — the March 2022 Fukushima earthquake stopped multiple Renesas lines, though they recovered within roughly ten days.

The Kanto corridor — equipment, materials and headquarters

The Tokyo metropolitan region and its surrounding prefectures constitute Japan’s densest concentration of semiconductor capability, even though relatively little wafer manufacturing happens there.

Tokyo holds headquarters for most major equipment and materials firms, plus the government ministries, industry associations and financial institutions you will need to engage.

Ibaraki — Renesas Naka, plus a considerable research and equipment presence. Yamanashi and Nagano — Tokyo Electron and precision components. Kanagawa — R&D centres and materials operations. Toyama and Niigata — a materials and chemicals concentration, including significant Shin-Etsu operations.

Central Japan (Aichi, Mie, Shizuoka) deserves separate mention: Kioxia’s Yokkaichi complex in Mie is one of the world’s largest NAND manufacturing sites, and Aichi’s automotive cluster drives substantial power and automotive semiconductor demand.

For foreign companies: if you are selling into Japanese equipment or materials makers, or need government and financial access, Kanto is where you must be present. If you are supporting fabs, you need people near the fabs — Kanto presence alone will not serve Kumamoto customers acceptably.

Practical siting guidance

| If your priority is… | Locate in… | |—|—| | Selling to equipment/materials makers, government and finance access | Tokyo / Kanagawa | | Fab support for leading-edge and mature foundry | Kumamoto (Kikuyo, Koshi, Ozu) | | Early positioning in a forming cluster | Chitose, Hokkaido | | Memory and NAND | Mie (Yokkaichi), Iwate (Kitakami) | | Automotive and power semiconductors | Aichi, Kyushu | | Cost-efficient operations with skilled labour | Tohoku |

The concentration problem

Japan’s clusters produce real efficiencies: shared supplier bases, dense talent pools, fast physical support response. They also mean that a substantial share of certain global product categories depends on a small geographic area sitting on an active fault system.

This is not an argument against operating in Japan — it is an argument for explicit dual-siting where your product allows it, and for understanding your suppliers’ recovery profiles before you need them. Notably, the 2026 recovery pattern was fast and predictable: inspection, repair, phased restart. That predictability is itself worth something in a supply chain where other disruption types drag on for quarters.

Related: Where Japan Actually Sits in the Supply Chain · [Japan’s National Semiconductor Strategy]

Written and edited by Masanori Takano, Chief Executive Officer of TechMedix Institute, Inc.