Japanese Pioneers

Hiroe Osafune was born in Okayama Prefecture in 1917. After graduating from the Faculty of Technology at Tokyo Imperial University in 1941, he entered Nippon Electric Company, Limited (later NEC Corporation) and started his career in one of the company’s research laboratories in 1942. He became the manager of the technical department at the semiconductor factory in 1964, and then became a vice president and general manager of the semiconductor division in 1964. After retiring from NEC in 1979, he held positions as a chairman of NEC Electronics Corporation and a chairman of Nippon Electric Company’s Yamaguchi operation, among other positions.

A pioneer in semiconductor research in Japan, Osafune made a tremendous contribution to the launch of NEC’s semiconductor business. Immediately after joining Nippon Electric Company, Limited in 1941, he was engaged in the study of phosphors for cathode-ray tubes. He was among the first to start semiconductor research after Bell Laboratories announced its invention of the transistor after World War II. He succeeded in test production of a microwave silicon diode in 1950 at the request of the microwave group within the company, and this device entered low-volume production in 1951.

He next worked on developing transistors, and obtained a grant from the Ministry of Education for research into test manufacturing point-contact transistors. Osafune successfully completed a single-crystal of germanium and then made a working transistor in 1953, and followed this with the experimental fabrication of high- and low-frequency junction-type transistors and power transistors by 1955.

He also stood out in commercializing the mesa and planar epitaxial transistors, which came to be the mainstream of silicon transistors. Based on these achievements, by 1962 he had developed about ten types of bipolar semiconductor IC, including AND gates, NOR gates, and flip-flops.

To this day, Osafune is legendary for acquiring an exclusive license in Japan for NEC of the patent on planar transistors from Fairchild Corporation.