DRAM 산업의지식확산, 기술궤적과산업주도권의이동:특허인용 네트워크 분석과 신슘페터주의 기술경제학

This paper analyzes the citation network of DRAM-related patents focusing on technological change and the shift of market dominance. As a whole, the results of the analysis is consistent with characteristics of the DRAM industry which founded by existing literatures. This founding indicates that a citation network analysis can be an effective in studying technological and industrial change. In addition, through a citation network analysis, we found some features of the DRAM industry that were not found by existing literatures. By visualization of the citation network, three clusters are observed in the citation networks. Cluster 1 formed first, and cluster 2 and 3 followed in order. Cluster 1 is characterized by product innovation, and dominated by American venture firms. Mixture of product and process innovation is characteristics of Cluster 2. Large American and Japanese firms lead formation of Cluster 2. Patents of Cluster 3 are mostly related with process innovation and granted by Micron, Korean large firms and Taiwanese firms. Clusterization means discontinuity of technological change, which can be the reason of the shift of market dominance. The result of main path analysis reveals that the main path of the network goes from Japanese and American firm to Taiwanese firms via ITRI (Industrial Technology Research Institute), Taiwanese government research unit, which is consistent with stylized facts found by existing literatures on the DRAM industry. However, the main path covers only small area of the network. This also can be evidence of technological discontinuity.