Friday 12 June 2009

Cramming more components onto integrated circuits

There are a number of ways to illustrate the revolutionary growth in computational power over the past 50 years or so, but perhaps one of the easiest is as a simple folk story. 

In the good old days of the late fifties, 1958 to be exact, an electronics engineer at Texas Instruments called Jack Kilby built the very first integrated circuit (IC); it was a major technical achievement and was composed of five separate components (resistors, transistors and capacitors). 

By 2004 Intel introduced the Itanium 2 chip with with 9MB cache and 592 million transistors..  

These arbitrary dates, 1958 and 2004, can be used to bookend an incredible growth in computer complexity and power. What is almost as surprising as this incredible growth is the fact that it was predicted in advance in 1965 by someone who was in the thick of the then new electronics industry. The paper in question was published under the heading, “The experts look ahead” and was written by the founder of Intel, Gordon Moore, when he was the Research & Development Director of Fairchild Semiconductor. The article had a typical engineering swagger and directness about its title; “Cramming more components onto integrated circuits”, and it appeared in a trade journal called Electronics (Moore 1965). 

In keeping with the down to Earth tone of the title was the simple and crystal clear message that the author spelt out. Moore predicted that the pace of technical developments in the semi-conductor industry would be extremely rapid. They would follow a growth law, now known as Moore's law, such that there would be a rough doubling of the number of transistors you could fit onto an integrated chip every 2 years. Moore predicted that, 

“Certainly over the short term this rate can be expected to continue, if not to increase. Over the longer term, the rate of increase is a bit more uncertain, although there is no reason to believe it will not remain nearly constant for at least 10 years”. 

In fact the doubling every two years that Moore predicted has remained essentially constant for the past 40 years.