Both p-type and n-type semiconductor is the classification of extrinsic semiconductors. The major factor that generates a difference between p-type and n-type semiconductor lies in their doping material. A p-type semiconductor material is formed by the addition of group III elements or we can say trivalent impurity to a pure (intrinsic) semiconductor. On the contrary, the n-type semiconductor material is formed by the addition of group V elements i.e., a pentavalent impurity to a pure or intrinsic semiconductor.
Some other factors also exist that generates major differences between the two. We will discuss these differences in detail but before proceeding towards that have a look at the contents that are to be discussed under this article.
Content: P-Type Vs N-Type Semiconductor
- Comparison Chart
- Definition
- Key Differences
- Conclusion
Comparison Chart
| Parameter | P-Type | N-Type |
|---|
| Impurity doped | Trivalent impurity | Pentavalent impurity |
| Also known as | Acceptor atom because of presence of additional hole. | Donor atom due to the existence of additional electron. |
| Doped group | Group III elements. For eg - boron, gallium, indium, aluminium etc. | Group V elements. for eg - arsenic, antimony, bismuth, phosphorus etc. |
| Majority carriers | Holes | Electrons |
| Minority carriers | Electrons | Holes |
| Conductivity | Due to presence of holes. | Due to presence of electrons. |
| Presence of fermi level | Fermi level appears closer to the valence than the conduction band. | Fermi level is present nearer to the conduction band than the valence band. |
| Concentration of electrons | Low | Very high as compared to p type semiconductor |
| Concentration of holes | High | Comparatively less than p type semiconductor. |
Definition of P-type semiconductor
When a pure or intrinsic semiconductor is doped with group III elements of periodic table like boron, gallium, aluminium etc. that these are known as the p-type extrinsic semiconductor. These are called so because doping these elements will lead to the presence of an extra hole in the valence shell of the atom.
Let us have a look at the figure shown below that represents doping of aluminium to a pure silicon material:
As we know that an aluminium atom contains 3 electrons at its valence shell. Also, silicon contains total of 4 electrons at its valence shell. So, 3 valence electrons of aluminium atom make covalent bonds with 3 electrons of silicon. However, in this case, a vacancy of an electron (or a hole) appears. The movement of this hole is mainly responsible for the conduction in the p-type semiconductor to take place. Hence, in this case, charge carriers are holes rather than electrons.
Let us now have a look at the energy level diagram of a p-type semiconductor:
Here, we can see that the Fermi level is present near the valence band. As it is clear from the above figure that there exists a very small energy difference between valence band and the acceptor energy level. Thus, electrons easily drift to acceptor energy level creating a vacancy of electrons. Hence, producing holes in the valence band.
Definition of N-type semiconductor
N-type extrinsic semiconductors are formed when group V elements like phosphorus, antimony, bismuth etc. are doped to a pure semiconductor crystal. These are called so because doping these elements will cause the presence of an additional electron in the valence shell of the atom.
The figure below represents the doping of phosphorus element into a pure silicon material:
We already know that phosphorus consists of 5 electrons at its valence shell. When it is doped with pure silicon having 4 electrons at the valence shell then it forms 4 covalent bonds. This leads to the presence of an unbounded electron that is held free to move into the conduction band. This electron is known as a free electron and its movement raises the conductivity of the material.
Now, have a look at the energy band diagram of N-type semiconductor:
Here, from the figure, it is clear that the existence of the Fermi level is near the conduction band. We can see that the small energy difference exists between donor energy level and the conduction band. So, less energy is needed by the electrons to reach the conduction band.
Key Differences between P-Type and N-Type Semiconductor
- A p-type semiconductor is formed when group III elements are doped to a pure semiconductor material. As against, an n-type semiconductor is formed when group V elements are doped to an intrinsic semiconductor.
- As elements like boron, gallium, indium etc. are doped to form p-type semiconductor thus it produces an additional hole hence also known as acceptor atom.
On the contrary, elements like arsenic, antimony, bismuth etc. are doped in order to have n-type semiconductor hence it produces an additional electron thus also termed as donor atom. - Another factor that generates a key difference between p-type and n-type semiconductor is that in case of p-type semiconductor holes are the majority carriers. While in case of n-type semiconductor electrons act as majority carriers.
- The minority carriers in case of the p-type semiconductor are electrons whereas in that of n-type semiconductor these areholes.
- As we know that the conductivity of the device depends on the majority carriers. Thus in the p-type semiconductor, holes are responsible for current conduction. On the contrary, incase of an n-type semiconductor, electrons are responsible for current conduction.
- The fermi-level in case of p-type semiconductor appears closer to valence band than that of the conduction band. As against, the Fermi level in case of n-type semiconductor exists near the conduction band.
- The concentration of holes is more than electrons in case of p-type semiconductor material. While in n-type semiconductors the concentration of electrons is greater than holes.
Conclusion
So, from the above discussion, we can conclude that a p-type semiconductor is abbreviated so because these are positive semiconductors due to presence of extra holes. Whereas, n-type semiconductors are termed as negative semiconductors because of the presence of extra electrons.
Related Terms:
- NPN Transistor
- Difference Between Half Wave and Full Wave Rectifier
- Difference Between Intrinsic and Extrinsic Semiconductor
- Oscillator
- Difference Between LED and Photodiode
FAQs
N-type semiconductors have an excess of electrons, while p-type semiconductors have an excess of "holes" where an electron could exist. When n-type and p-type semiconductors meet in a PN junction, they form a boundary where electrons from the n-type region fill the holes in the p-type region, creating a depletion zone.
What is the difference between n-type and p-type semiconductor table? ›
1) The charge carriers in n-type semiconductor are holes while those in p-type semiconductor are electrons. 2) With n-type semiconductor, the conductivity is controlled by free electrons, which run through the substance like a fluid, while conduction in p-type is controlled by “holes” or positive charge carriers.
How do you tell if a semiconductor is p-type or n-type? ›
In its most basic form, an N-type has one too many electrons, and a P-type needs one more. Together, they give what the other needs and produces better electrical conductivity. All in all, a computer chip is made up of billions of these diodes.
How can you distinguish p-type and N-type semiconductors using hot probe method? ›
The hot probe is connected to the positive terminal of the multimeter while the cold probe is connected to the negative terminal. While applying the cold and hot probes to an n-type semiconductor, positive voltage readout is obtained in the meter, whereas for a p- type semiconductor, negative voltage is obtained.
Which of the following statements correctly describes the difference between n-type and P-type semiconductors? ›
Answer: The polarity of the charge carriers. "N(negative)-type" semiconductors have negative charge carriers (unbond electrons), while "p(positive)-type" have positive charge carriers, which actually are unrealized bonds that move against the current of electrons, as if they were real positive charges.
How do you classify p-type and N-type semiconductors? ›
Chemical elements or atoms (B, Ga, Tl, Al and In) with smaller atomic energy level spacing compared to atomic Si leads to p-type semiconductors (indicated with smaller ξ), while chemical elements (Sb, Bi, As and P) with larger atomic energy level (again relative to atomic Si) lead to n-type semiconductors.
What are the two characteristics of n-type and P-type semiconductor? ›
| n-type Semiconductor | p-type Semiconductor |
|---|
| ( i ) | It is formed by doping pentavalent impurities | t is doped with trivalent impurities. |
| $ ( i i ) | The electron are majority carriers and holes are minority carriers ( n e >> n h ) . | The holes are majority carriers and electrons are minority carriers ( n h >> n e ) . |
Jan 9, 2020
We can easily identify whether a semiconductor is p-type or n-type by using Hall Effect. If the voltage produced is positive then the material is said to be p-type and if the voltage produced is negative then the material is said to be n-type.
How to tell if a semiconductor is n-type or p-type Hall effect? ›
A positive sign for the Hall coefficient indicates that the majority carriers are holes and semiconductor is P-type. A negative sign for the Hall coefficient indicates that the majority carriers are electrons and semiconductor is N-type.
What is an example of an n-type semiconductor? ›
N-type semiconductor examples are silicon doped with arsenic, silicon doped with phosphorus, arsenic doped with Germanium, Germanium doped with phosphorus, and so on are n-type semiconductor examples.
you can perform hall effect to identify whether the its n or p type along with its mobility. best of luck .. :) We can determine the type of semiconductor that is p-type or n-type by using Hall Effect voltage. I = current flowing through the material.
What is the difference between n-type and p-type transistors? ›
N-type transistors conduct when a logical "1" is applied, allowing current to flow from the power supply to the output. P-type transistors conduct when a logical "0" is applied, allowing current to flow from the power supply to the output. This combination forms the basis for digital logic circuits and microprocessors.
Is p-type semiconductor positive or negative charged? ›
No, a p-type semiconductor is not positively charged because they have a large number of holes and a small number of free electrons, Since, total number of holes is equal to total number of acceptor ions which have opposite charges to each other, therefore they cancel as a result p-type semiconductor is electrically ...
What is the basic difference between p-type and n-type semiconductor? ›
In the case of N-type semiconductor, the majority of charge carriers move from low potential to high potential. In the case of a P-type semiconductor, the majority of charge carriers move from high potential to low potential. The donor energy level is close to the conduction band in the case of N-type semiconductors.
What is the difference between P and N material? ›
Introduction: The Essential Duo of Modern Electronics
N-type semiconductors have an excess of electrons, while p-type semiconductors have an excess of "holes" where an electron could exist.
Which best describes a p-type semiconductor? ›
Neutral. Explanation for the correct option: A p-type semiconductor is a semiconductor created by doping an intrinsic semiconductor with an acceptor impurity. In a p-type semiconductor, a tetravalent semiconductor like silicon or germanium is doped with a trivalent impurity like aluminium, gallium, or boron.
What does P and N stand for in semiconductors? ›
The "p" (positive) side contains an excess of holes, while the "n" (negative) side contains an excess of electrons in the outer shells of the electrically neutral atoms there. This allows electric current to pass through the junction only in one direction.
What are p-type and n-type semiconductor symbols? ›
A p-type semiconductor is one with a preponderance of holes; an n-type semiconductor has a preponderance of conduction electrons. The symbols p and n come from the sign of the charge of the particles: positive for holes and negative for electrons.
What is the difference between n-type and p-type silicon wafers? ›
P-type silicon wafers are simple to manufacture and have low costs. N-type silicon wafers typically have longer minority carrier lifetimes, and the efficiency of solar cells can be made higher, but the process is more complicated. N-type silicon wafers are doped with phosphorus, which has poor solubility with silicon.
What is the difference between intrinsic and n-type semiconductor? ›
In an intrinsic semiconductor, the number of electrons is equal to number of holes. In case of extrinsic semiconductors, the number of holes and electrons are not equal. In a P-type semiconductor, the holes are more than electrons while in an N-type semiconductor, the electrons are more than holes.
