What is depletion in semiconductor?
What is depletion in semiconductor?
[ dĭ-plē′shən ] A region in a semiconductor device, usually at the juncture of P-type and N-type materials, in which there is neither an excess of electrons nor of holes. Large depletion regions inhibit current flow. See also semiconductor diode.
How is a pn junction formed in a semiconductor?
P-n junctions are formed by joining n-type and p-type semiconductor materials, as shown below. Since the n-type region has a high electron concentration and the p-type a high hole concentration, electrons diffuse from the n-type side to the p-type side.
What is junction potential in semiconductor?
This potential is called the junction potential or contact potential. The presence of the electric field leads to band bending, with the bands bending up, moving from n-type to p-type semiconductor. The band diagram when the pn junction is formed (at equilibrium) is shown in figure 3.
What is the function of semiconductor diode?
A diode is a semiconductor device that essentially acts as a one-way switch for current. It allows current to flow easily in one direction, but severely restricts current from flowing in the opposite direction.
What is the use of semiconductor diode?
Diodes are semiconductor devices that effectively block current in one direction while allowing current flow in the other. An ideal diode, therefore, acts like a switch that is open in one direction and closed in the other.
What is the depletion layer in P-N junction?
This space-charge region on either side of the junction together is known as the depletion region as the electrons and holes taking part in the initial movement across the junction depleted the region of its free charges.
What is P-N junction define depletion region?
Depletion region or depletion layer is a region in a P-N junction diode where no mobile charge carriers are present. Depletion layer acts like a barrier that opposes the flow of electrons from n-side and holes from p-side.
What occurs when a pn junction is first formed?
12. ___ occurs when a pn junction is first formed….Exercise :: Diodes and Applications – Filling the Blanks.
| A. | produce a nearly-constant dc voltage |
|---|---|
| B. | reduce the output voltage |
| C. | increase the ripple voltage |
What are trivalent and pentavalent impurities?
Pentavalent impurities Impurity atoms with 5 valence electrons produce n-type semiconductors by contributing extra electrons. Trivalent impurities Impurity atoms with 3 valence electrons produce p-type semiconductors by producing a “hole” or electron deficiency.
What causes junction potential?
When a cell contains a boundary between two electrolytic solutions of different composition or concentration, a liquid junction potential is developed due to the diffusion of the various components at characteristic rates in the boundary zone.
What is pn junction how does current flow in pn junction diode?
In a forward-biased PN junction, once the barrier voltage is overcome, it conducts a current. The externally applied potential pushes majority carriers toward the junction where recombination takes place, allowing current flow.
What is the formation of p-n junction diode?
For the formation of p-n junction diode, p-type and n-type semiconductor materials are combined together. There is a movement of electrons to the p-type material and movement of holes to the n-type material. Due to this movement, there is a formation of the depletion region.
Which Terminal supplies free electrons to the p-n junction in a semiconductor?
Anode terminal or negative terminal supplies free electrons to the p-n junction. In other words, anode terminal is the source of free electrons, the free electrons begins their journey at negative or anode terminal and fills the large number of holes in the p-type semiconductor.
What is the formula used in the p-n junction?
The formula used in the p-n junction depends upon the built-in potential difference created by the electric field is given as: \\(E_{0}=V_{T}ln[\\frac{N_{D}.N_{A}}{n_{i}^{2}}]\\) Where,
What happens when potential is applied to a PN junction?
PN Junction when Potential is Applied Different properties are noticed, depending on the width of the depletion region. If the positive potential is applied in such away the P type area becomes positive and therefore the N type becomes negative, holes travel towards the negative voltage.
