This paper uses patent data from companies in the Chinese semiconductor manufacturing industry chain to explore the impact of knowledge maturity and inventor characteristics on key and core technology innovation. The study finds that the impact of knowledge maturity on key and core technology innovations exhibits an inverted U-shaped relationship. Compared with low-maturity and high-maturity knowledge, medium-maturity knowledge can significantly promote key and core technology innovation. Further analysis shows that the scale of the inventor group makes the inverted U-shaped curve between knowledge maturity and key and core technology innovation flatter, while the experience of inventors makes it steeper.