Four-Phase Systems Garrett AiResearch MP944 Intel 4004 PMOS Ted Hoff Federico Faggin Masatoshi Shima Stanley Mazor Intel Tadashi Sasaki Masatoshi Shima Busicom microprocessor microprocessors
The subject of exactly which device was the first microprocessor is contentious, partly due to lack of agreement on the exact definition of the term "microprocessor". The earliest multi-chip microprocessors were the Four-Phase Systems AL-1 in 1969 and Garrett AiResearch MP944 in 1970, developed with multiple MOS LSI chips. The first single-chip microprocessor was the Intel 4004, developed on a single PMOS LSI chip. It was designed and realized by Ted Hoff, Federico Faggin, Masatoshi Shima and Stanley Mazor at Intel, and released in 1971. Tadashi Sasaki and Masatoshi Shima at Busicom, a calculator manufacturer, had the initial insight that the CPU could be a single MOS LSI chip, supplied by Intel.
