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What else can I help you with?
Why can't the potential barrier of a diode be used as a voltage source?
The potential barrier of a diode is caused by the movement of electrons to create holes. The electrons and holes create a potential barrier, but as this voltage will not supply current, it cannot be used as a voltage source.
Which has greater mobility in intrinsic semiconductor Electrons or holes?
The mobility of electrons is always greater than holes. Only the number of electrons and holes would be same in an intrinsic semiconductor.
Why the negative half cycle cannot pass through the diode?
When the diode is reverse biased a depletion zone is formed at the junction between the cathode and anode, that lacks current carriers (it has neither electrons or holes). Without current carriers, the diode acts as an open circuit, blocking current flow.
Why is current not zero in reverse biased semiconductors?
This is a lengthy answer. I tried to cover all the bases b/c I'm not sure how much you already know about semiconductors.Background:A semiconductor junction, such as that in a diode, is a connection between an N-type material and an P-type material. The N-type material has extra electrons and the P-type material has extra "holes," or a lack of electrons. Where the two materials meet, an area with neutral charge called a depletion region forms.In a forward-biased diode, electrons trying to travel from N to P have no problem because of the abundance of extra electrons in the N-type material. The same thing happens to the positive charge carriers (holes) in the P-type material. The depletion region (.7 volts wide in a silicon diode) collapses and electrons exchange with holes through the junction -> A current flows.In a reverse-biased diode, the depletion region (an insulator) actually grows because the unlike charges presented to each side of the junction pull the charge carriers (both electrons and holes) further away from the junction in the center. This prevents most of the current from flowing through the region.Answer:Because semiconductor technology is not perfect, a few charge carriers exist where they shouldn't. some electrons exist in the P-type material and some holes exist in the N-type material. These "minority carriers" are able to move through the depletion region of a reverse biased diode, and allow a small current to flow.Adding heat or exposing the junction to light will increase the number of minority carriers, and so more reverse-bias current will flow. This is actually useful information- for instance, by measuring the reverse current through a photodiode, you can determine how much light is hitting the junction and use this to create an optical receiver or light sensor.Keep your diodes cool,anp
How is the NPN transistor different from the PNP transistor?
"P" is for Positive and "N" is for Negative So basically put a PNP Transistor Would use N to Switch P, in the name "PNP" or "NPN" the first character is for the polarity of the Collector-pin, the second for the Base-Pin, and the third for the Emmiter-pin. So if you have a PNP Transistor you can`t just replace it with an NPN as the polarities differ. If you can find a way to change those polarities then sure it could work. The Collector-pin basically receives the bigger current. The Base-pin determines how much of that current will be transferred to the emmiter-pin. So in a PNP the base current could for example be 0V and the Collector 5V, this will allow a free flow of current from Collector to Emmiter, the usage of a transistor in many cases is to switch high current with lower current. The main difference is that a PNP transistor uses "holes" as carriers and an NPN transistor uses electrons as carriers (It is to be remembered that the flow of current is always in the direction opposite to that of the flow of electrons). The difference in the symbol for the two transistors are that the PNP transistor will have an arrow pointed to the base from the emitter, and the NPN has it pointing outside.
What are the majority and minority current carriers in an N-type and a P-type semiconductor?
In an N-type semiconductor, majority current carriers are electrons, while minority current carriers are holes. In a P-type semiconductor, majority current carriers are holes, while minority current carriers are electrons.
What term refers to holes and electrons in the operation of a transistor?
current carriers
Anode current in an thyristor is made up of?
Holes and electrons
Which particles carry an electric current around a circuit?
The particles that carry charge around a circuit are electrons. In some semiconductors, missing electrons in a crystalline structure (of silicon or germanium), caused by adding special impurities, form spaces called "holes" where there is a missing electron. These "holes" can also travel but, in the end, it is electrons that move in the opposite direction to fill those holes that carry the current.
What are the two types of current flow in a semiconductor?
The two types of current flow in a semiconductor are electron current, which is due to the movement of negatively charged electrons, and hole current, which is due to the movement of positively charged "holes" left behind when electrons move through the crystal lattice.
What is whole current in p type semi conductor?
In semiconductor two charge carriers are present i.e holes and electrons.The current is rate of flow of charges.so in ptype semiconductor the current is the sum of current due to holes and electrons.But current due to holes is more compsred to electrons in ptype.
Carrier of electric current in germanium semiconductor?
electrons or holes depending on doping, as in any semiconductor.
What is significance of depletion region?
Depletion region is the region where current carriers such as electrons and holes are absent.
Why cant there be hole current in the conduction band?
In a semiconductor, the conduction band is filled with electrons, which are negatively charged. Holes represent the absence of electrons in the valence band, not in the conduction band. Since the conduction band is typically occupied by electrons, it cannot have holes; instead, holes exist in the valence band where electrons are missing. Therefore, while there can be free electrons in the conduction band, holes are specifically a feature of the valence band.
Is SCR the unipolar device?
SCR is bipolar device since current is due to both electrons as well as holes.
At what energy level does hole current occur?
Hole current occurs at the valence band energy level in a material with a band gap, where electrons are absent and holes behave like positive charge carriers. This process involves the movement of holes in the direction opposite to the movement of electrons in a conducting material.
How does motion of electron in n type substance differes from motion of hole in p type substance?
Electrons constitute electronic current in n-type substance and holes constitute conventional current in p-type substance.The motion of electron in a n-type substance is opposite to that of holes in a p-type substance.
