How integrated circuits work

Found in every electronic device you own, the integrated circuit is absolutely fundamental in the modern world

When the greatest inventions of the 20th century are weighed up for their merits there are few people who think of the integrated circuit. They often name some of the devices which it has enabled – which isn’t difficult, as they are numerous – but rarely do we celebrate the bundle of transistors that was first crudely assembled in 1958.

In many ways that is totally understandable. The integrated circuit is by its very small – or in a more modern and accurate context, nanoscale – nature largely unimpressive. It’s essentially a handful of metal and semiconductor components strapped together to perform invisible functions. But it is through these circuits that all modern electrical devices operate, with everything from personal computers through to smartphones and televisions relying on them to perform all number of essential processes.

An integrated circuit is an assembly of miniaturised active and passive devices; active examples include transistors and diodes, while passive examples include capacitors and resistors. Together they are built up on a thin substrate of semiconductor material such as silicon – which is where the US’ chip-making region Silicon Valley gets its name.

Combined these structures create a computer chip, which typically range from a few millimetres up to a few centimetres – such as with CPUS – in size. These chips protect their numerous internal integrated circuits with plastic shells and are combined to create the super-powerful electronic devices many of us couldn’t live without today.

In this feature How It Works takes a closer look at the science, manufacturing processes and history of the tiny integrated circuit, charting its development over 60-plus years and contemplating what integrated circuits may have in store for the future.