For the last 4 decades, the electronics industry has been evolving according to what is known as "Moore's Law", which states that the power of computing processors doubles every two years. During his time at Intel, one of its founders, Gordon Moore, came to the conclusion that the number of transistors that industry could fit on a processor chip would double every 24 months. And, as we can see, something like that is really happening: computers and phones that seemed powerful a few years ago already look obsolete compared to the latest innovations. In the meantime, manufacturers are introducing more and more microprocessors, capable of even more operations per unit time.
Transistors, those tiny semiconductors, are the backbone of all modern technology. Every year they get smaller and smaller, but there has to be a limit to how much they can shrink, right? Yes, and we are getting very close to it A modern transistor consists of two semiconductors with a surplus of electrons and a semiconductor with a deficiency of electrons in between. Above them are a control gate and a floating gate, insulated with a dielectric. When a voltage is applied to the control gate, some of the electrons will move to the floating gate due to the tunnel effect. The floating gate, which receives a negative charge from the electrons "planted" on it, will interfere with the current flow through the transistor. In this case, the transistor will have a value of "1". The size of the control gate plays a big role here. If it is smaller than 5 nm (nanometers), then electrons will leak out of the floating gate due to the same tunnel effect, and the transistor will not work properly.
Modern processors use transistors with a control gate around 20 nm, and scientists are looking for ways to reduce them to 5 nm.