The intensified competition amidst the new round of technological changes and industrial revolutions has led to substantial advancements in the manufacturing industry. However, there is a notable dependency on imports in key core technology areas, such as next-generation information technology and biomedical industry, posing significant challenges. In response, the report of the 20th National Congress of the Communist Party of China in 2022 made important strategic deployments, proposing to resolutely win the battle for mastering key core technologies. The unique and in-depth professional technology accumulated by enterprises in specific knowledge fields for a long time is the key driving force to promote the breakthrough of key core technologies. In this context, SRID enterprises, leveraging their professional expertise and deep cultivation in specific segments of the industrial chain, are crucial for breaking through key core technologies.

There is a consensus in literature on the importance of knowledge resources in driving breakthroughs in key core technologies. However, existing research primarily focus on exploring this through collaboration networks, lacking literature that examines the impact mechanism of a firm's internal knowledge base on key core technology breakthrough, especially empirical research on the degree of technological specialization among SRDI enterprises.

This study takes the new generation of information technology industry in the first five batches of listed small giant enterprises in China as the research object, and deeply explores the effect of technological specialization on the breakthrough of key core technologies, the mediating role played by knowledge search in this process, and the moderating role of knowledge integration capabilities. The results show that there is an inverted U-shaped relationship between technology specialization, knowledge search and key core technology breakthroughs. A firm's specialized knowledge base and externally searched heterogeneous knowledge provide a direct resource base for breakthrough innovations in key core technology fields. The moderating effect analysis shows that the inverted “U” shaped relationship between technology specialization and key core technology breakthroughs is mediated by knowledge search. Enterprises will conduct knowledge searches based on their own knowledge characteristics and, through continuous cooperation and exchanges with the outside world, provide more extensive or in-depth heterogeneous knowledge resources for breakthrough innovations in key core technology fields, thereby freeing enterprises from resource constraints. In addition, knowledge integration ability moderates the role of technology specialization and knowledge search on key core technology breakthroughs, respectively. High knowledge integration ability will alleviate the negative impact of over-specialization and over-search, and when it breaks through a certain threshold, it can completely offset the negative impact and further promote key core technology breakthroughs.

These findings hold significant importance for enterprises to facilitate knowledge search by deepening their own specialized knowledge, thereby promoting breakthroughs in key core technologies: (1) SRDI enterprises should deepen core technology research while exploring diversified technologies, forming dedicated teams and building a knowledge base to avoid the specialization trap. (2) SRDI enterprises should integrate internal and external resources by collaborating across sectors and deeply mining existing knowledge, utilizing advanced tools for systematic analysis and integration. (3) Constructing a knowledge sharing platform and nurturing a multidisciplinary team will enhance resource integration, facilitating efficient knowledge conversion and application.

This study emphasizes the complementary synergy between knowledge search and technology specialization, expands the research scope of key core technology breakthroughs at the micro level, and provides theoretical guidance and decision-making reference for enterprises to promote key core technology breakthroughs.