Jack Kilby, the US inventor of the integrated circuit which formed the basis of the computer chip, has died aged 81, after a battle with cancer.
Jack Kilby's contribution ranks alongside those of Ford and Edison
The discovery that transistors could be shrunk on to a single block of silicon paved the way for personal computers, mobile phones and microwave ovens.
Experts rank his contribution to invention alongside those of Henry Ford and Thomas Edison.
It spawned a multi-billion dollar industry and earned him a Nobel Prize.
Jack Kilby grew up in Kansas and fulfilled his ambition to become an engineer at the University of Illinois.
He joined Texas Instruments soon after and made his discovery working alone in the laboratory while his colleagues enjoyed a summer vacation.
Kilby and Texas Instruments were the first to patent the new transistor but his rival Bob Noyce is widely credited with making it possible to mass produce it.
Mr Noyce went on to co-found Intel with Gordon Moore.
The first circuit built by Mr Kilby was about half the size of a paper clip. It is now possible to squeeze about 100 million transistors in the same space.
Part of the drive to develop an integrated circuit was the space race with the Soviet Union.
The invention led Texas Instrument to win a contract to supply chips for the Minuteman rocket.
Mr Kilby retired from Texas Instruments in 1983 although he continued to be a consultant and the firm's research complex is named after him.
During his career Mr Kilby earned more than 60 patents, won the National Medal of Science and was inducted into the National Inventors Hall of Fame.