Amkor Technology Japan (formerly J-Devices)
Japan's large outsourced assembly and test company, formerly J-Devices, which took over back-end work from Japanese chipmakers and is now part of Amkor Technology.
J-Devices（アムコー・テクノロジー・ジャパン）・Chipmakers, foundries and OSATs・Last updated: October 27, 2026
Overview
J-Devices took over assembly and test operations from Japanese semiconductor makers such as Panasonic, Fujitsu and Renesas. Amkor Technology took full ownership in 2016, and the company now operates as Amkor Technology Japan.
It assembles BGA, CSP and QFN packages and wafer-level CSPs.
Business: Outsourced semiconductor assembly and test (OSAT)
Why it matters
- Japanese chipmakers moved much of their back-end production to outside contractors, and this company is where much of it went.
- Being part of Amkor connects Japanese customers to a global assembly network.
Main products
- •BGA, CSP and QFN packages
- •Wafer-level CSP (WLCSP)