Hall Effect

In certain materials, like semiconductors, the Hall effect occurs when an electric current passes through them in the presence of a magnetic field. When the magnetic field is perpendicular to the direction of current flow, it causes the charge carriers (like electrons or holes) in the material to experience a force. This force deflects the charge carriers to one side of the material, creating a voltage difference perpendicular to both the current and magnetic field directions, which is called the Hall voltage.

The Hall effect allows to measure important properties of the material, such as its type (whether it is an N-type or P-type semiconductor) and the density and mobility of charge carriers. It is used in various applications, including sensors, current measurements, and even in certain electronic devices. By studying the Hall effect in semiconductors, scientists and engineers can better understand and design electronic components and systems.

Difficult eh? If you are not bored by now I congratulate you. We will use a river-boat analogy to explain this better:

1. The River (Semiconductor): Think of a wide, calm river as our semiconductor material. It’s the path where things are going to happen.
2. The Boats (Electrons): Imagine tiny boats sailing down this river. These boats represent the electrons, the tiny charged particles that carry electric current.
3. The Wind (Magnetic Field): Now, let’s add some wind, which represents the magnetic field. The wind pushes the boats, just like the magnetic field affects the electrons.
4. Boat Gathering: When the wind (magnetic field) blows, it pushes the boats (electrons) to one side of the river. The boats start to pile up on that side, leaving fewer on the other side.
5. Voltage Difference (Hall Voltage): This piling up of boats on one side of the river creates a height difference in the water. That height difference is like a voltage. It’s the “Hall Voltage.”

So, in this analogy, the wind (magnetic field) pushes the boats (electrons) to one side, creating a height difference (Hall Voltage) in the river (semiconductor). This helps scientists figure out what’s happening inside the semiconductor.