1947 the first Transistor was invented by Bardeen, Brattain and Shockley in the Bell Labs in the USA.
Intel's 4004 IC chip, generally acknowledged as the world's first "microcomputer on a chip," was originally designed in 1969-70 for the Busicom (Japan) 141-PF desktop calculator.
1958 Jack Kilby invented the integrated circuit at Texas Instruments and got the Noble Prize. Comprised of only a transistor and other components on a slice of germanium, Kilby's invention, 7/16-by-1/16-inches in size, revolutionized the electronics industry.
1904 Sir John Ambrose Fleming invents the vacuum tube and diode.