Question: Are silicon chips that power our computers man-made or natural occurences?

Lynne Thomas answered on 17 Jun 2014:

Silicon chips are actually a complicated mixture of different layers (the electronics) but these are laid down on top of a silicon wafer. Silicon is a chemical element and it does occur on its own as a pure solid. However, it is more commonly found in sand as something called silica or quartz. This is a chemical compound called silicon dioxide (SiO2) so it has some extra oxygen in there which is chemically bonded to the silicon. For a silicon chip, we need to get to pure silicon. What they do is a process called electrolysis. This allows the two elements, silicon and oxygen, to be separated out just leaving the silicon. The silicon is heated to very high temperatures so it is melted or molten (around 1500 degrees) and then cooled to give very good quality single crystals of silicon. This means that the atoms of silicon are arranged in a very regular way in three dimensions. This happens by itself – we can’t put atoms where we want to in a crystal. These crystals are called ingots and they are then cut into things called silicon wafers.

Silicon has properties as a semiconductor and it is an entirely natural occurrence that it has this property. We have just developed ways in which we can use it. Some advanced methods are then used to deposit the electronics onto the surface of the silicon wafer to make the silicon chip and this is a man-made process.

This is the way that a lot of science works. We investigate a material and then we try and find ways that we can use it to make technology advance! Being a good scientist is about being able to find ways to use things once you have discovered them!