Microprocessor chips have a “heat sink” glued on top that looks like a series of fins. Why are they shaped like that?

Conduction is a process of heat transfer through the direct contact between two surfaces, and convection is the process of heat transfer through the movement of air, where hotter air rises and the cooler one sinks.

The rate of heat transfer is directly proportional to the surface area.

When the shape of the heat sink is in the form of a series of fins, there is more surface area than when the heat sink is a solid plane surface. Here, the heat is transferred by the convection process through the series of fins. As the surface area is greater due to the series of fins, more air can come into contact with the heat sink, and the rate of heat transfer increases. The heat generated within the chip is also removed by the heat sink through the process of conduction.