Abstract: The “Four Urgent Measures” proposed in the 1956 “12-Year Long-Term Plan” were supplementary measures for the “Two Bombs” Project. As one of the “Four Urgent Measures”, the development of semiconductor technology focused on transistors. Centered on Task 40, “Establishment of Semiconductor Technology”, and on the “Four Urgent Measures”, this paper examines the connection between transistor development and the “Two Bombs” Project, as well as the reasons for the rapid transition of China’s semiconductor technology from germanium to silicon. The paper points out that, driven by the “Two Bombs” Project and centered on the development of the 109B, 109C, and 156 machines, China’s semiconductor technology achieved a rapid transition from germanium transistors to silicon transistors and established a solid foundation for the development of integrated circuits. The driving force behind this rapid transition was the urgent need for national defense modernization. With strong support from the state, scientists returning from Europe and the United States made tremendous efforts toward this goal. There was also influence and assistance from the Soviet Union prior to 1960.

Key Words: “Two Bombs” Project; “12-Year Long-Term Plan”; Germanium transistor; Silicon transistor; Semiconductor technology