Why does gradient occur in a semiconductor?
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Why does gradient occur in a semiconductor?
The carrier particles, namely the holes and electrons of a semiconductor, move from a place of higher concentration to a place of lower concentration. Hence, due to the flow of holes and electrons there is a current. The change in the concentration of the carrier particles develops a gradient.
When electric field is applied across a semiconductor?
When an electric field is applied across the semiconductor, the electrons being negatively charged oppose the direction of the electric field and hence move in the opposite direction of the electric field. The holes being positively charged move in the direction of the electric field.
Why does a gradient occur in a semi conductor because of current flow because of diffusion current because of drift current because of difference in concentrations?
Why does a gradient occur in a semi-conductor? Explanation: As there is a different level of doping in the p and n regions of a semi-conductor, the carriers (either holes or electrons) move from a region of high concentration to a region of low concentration giving rise to diffusion current. 10.
What is drift and diffusion current in semiconductors?
Drift current is electric current due to the motion of charge carriers under the influence of an external electric field while diffusion current is electric current due to the diffusion of carriers leading to a change in carrier concentration.
Is it possible that both potential gradient and a concentration gradient to exist simultaneously within a semiconductor?
It is possible that both potential gradient and concentration gradient exist simultaneously within the semiconductor. In such a case, the total current will be sum of drift current and diffusion current.
What happens to the free electrons when an electric field is applied?
What happens to the free electrons when an electric field is applied? Explanation: The free electrons move in the direction opposite to that of field direction.
What happens to the electrons when an electric field is applied?
Answer: when an electric field is applied the free electrons moves in a direction opposite to that of field direction.
When an electric field is applied across the conductor electron moves?
Electrons move from higher potential to lower potential. When a conductor is connected to battery, electron move from negative terminal to positive terminal. If a free electron were there on negative terminal it would follow electric field to the positive terminal.
Which current is due to the difference in carrier concentration?
(1)If the concentration of the carriers differs then there exists concentration gradient. In order to overcome this and attain an equilibrium state, the process of diffusion takes place. The current generated due to this process is referred to as Diffusion Current.
In which of the following semiconductor The concentration of the holes and electrons is equal?
intrinsic semiconductor
In which of the following semiconductor, the concentration of the holes and electrons is equal? Solution: In the intrinsic semiconductor, ni=pi that is the number of the electrons is equal to the number of the holes. Whereas in the extrinsic conductor ni is not equal to pi.
On which of the following factors does the drift current in the semiconductor depends?
Drift current depends on the electric field and the concentration of the carrier gradient.
What is concentration gradient in semiconductor?
Concentration Gradient In any semiconductor, there is the presence of the concentration of electrons or holes. The difference in this concentration of electrons or holes is referred to as a concentration gradient. Diffusion current density is proportional to the concentration gradient.