VerifiedComplete answer:
Drift current | Diffusion current |
1. It is due to the movement of carriers in response to an implemented electric field. | 1. The motion of charge carriers from higher concentration to lower concentration produces diffusion current. |
2. Positive carriers or holes flow in the same direction as the electric field, while negative carriers or electrons flow in the reverse direction. | 2. When a semiconductor is doped non-uniformly, there is a non-uniform concentration of carriers or a concentration gradient. |
3. The net movement of charged particles creates a drift current in the identical direction as the implemented electric field. | 3. Nature’s way of achieving equilibrium, in this case, is through the diffusion of carriers, and this provides rise to a diffusion current. This process does not need an external electric field and depends primarily on the repulsive forces between carriers of the same charge highly concentrated in an area. |
4. The drift velocity rises with an increasing electric field and provides the mobility of the transmitters. | 4. The repulsive forces will drive carriers' diffusion, leading to a variation in concentrations and eventually a uniform arrangement. |
5. The drift current obeys Ohm’s law and is mainly affected by the external field and charge carrier concentration. | 5. The primary carrier concentrations also define the diffusion current's direction—the current progress to the direction where there is initially a higher density of electrons or a feebler concentration of holes. |
Note: The Diffusion current is proportional to the concentration gradient or how nonuniformly the carriers were initially scattered. Quite honestly, the current flows in the same direction as the flow of holes and opposite electrons.
