Electronics began in 1906, when Lee De Forest invented the triode. The simple idea of adding a grid electrode to the diode suddenly gave mankind the ability to use a small signal to control a large one, which led immediately to the amplifier, the oscillator and the fast switch; hence to broadcasting, computers, automation and many other wonders.
In 1947 Shockley, Bardeen and Brattain invented the transistor by exploiting the understanding of materials science that had been offered by quantum mechanics. Various other forms of transistor emerged, including the field effect transistor FET (which had actually been anticipated by Lilienfeld in Germany as early as 1928).
It was, however, perhaps a very much earlier invention by Senefelder in 1799, that was to participate in the most startling fusion of technologies. This was lithography, which has become familiar in the form of the offset litho press and photolithography.
In 1958 Jack Kilby of Texas Instruments had the idea of making circuits on one block of silicon. In 1959, Jean Hoerni and Robert Noyce at Fairchild developed planar technology, so by means of photolithography many transistors could be placed on one silicon chip. Now we can put millions of transistors on a chip and even make micro-miniature mechanical systems, such as sensors and actuators.
The 200-year-old invention of lithography changed the modern world.
John Brignell is emeritus professor of industrial instrumentation at the University of Southampton and editor of Number Watch