2025 Volume 39 Issue 4 Pages 374-388
"Advanced semiconductors" with a manufacturing process of 5 nm or less are attracting attention as there are active global movements, such as economic and political tensions between the US and China regarding TSMC and the launch of a factory in Japan. On the other hand, since "Moore's Law" in semiconductor industries, "legacy semiconductors" fabricated using older processing technologies also have important technical and industrial significance. In this paper, we summarize the significance of "legacy semiconductors" and ways to effectively utilize them as a tool for innovation.