0
What are the majority carriers in the base region of an npn transistor?
Wiki User
∙ 11y ago
holes are majority in base
Wiki User
∙ 11y ago
Add your answer:
Earn +20 pts
Why collector is made larger than base and emitter in a transistor?
Collector has larger area than base and emitter because base collector is reverse biased, hence the current flow here due to the minority carriers and the large power dissipation takes place by the majority carriers, this power dissipated in the form of heat.. To cool the device from heat we made the larger area........
Why base of transistor is lightly doped?
The width of the base is very thin to increase the majority carrier concentration gradient in the base region thereby enhancing the diffusion current and also to reduce the number of majority carriers lost due to recombination in the base.
Is active is a cutoff region of transistor?
The active region of a transistor is when the transistor has sufficient base current to turn the transistor on and for a larger current to flow from emitter to collector. This is the region where the transistor is on and fully operating.
Why transistor is called transistor?
Because in this device the resistance between two terminal respectively collector and emitter is changed by changing the base voltage that is it transfers the resistance between emitter and collector therefore it is called as TRANSISTOR. (TRANSFER OF RESISTOR)
What is cutoff region in transistor?
The cutoff region is when the transistor doesn't have sufficient base current to drive a larger current from emitter to collector. Therefore, the transistor does not turn on and stays shut off.
Why collector is made larger than base and emitter in a transistor?
Collector has larger area than base and emitter because base collector is reverse biased, hence the current flow here due to the minority carriers and the large power dissipation takes place by the majority carriers, this power dissipated in the form of heat.. To cool the device from heat we made the larger area........
Why base of transistor is lightly doped?
The width of the base is very thin to increase the majority carrier concentration gradient in the base region thereby enhancing the diffusion current and also to reduce the number of majority carriers lost due to recombination in the base.
Is active is a cutoff region of transistor?
The active region of a transistor is when the transistor has sufficient base current to turn the transistor on and for a larger current to flow from emitter to collector. This is the region where the transistor is on and fully operating.
Why two diode join cant act as transistor?
No, it is not possible because in transistor the depletion layers formed in Emitter-Base Junction & Collector-Base Junction are penetrable by both current carriers but in this case of two diodes; the formed depletion region are not penetrable for current carriers (hole &electron). Also, a transistor works only because the base layer is very thin. You won't get that thin layer between emitter and collector just by connecting two diodes together. This thin base layer places the Emitter and Collector in very close proximity to each other. This allows majority carriers from the emitter to diffuse as minority carriers through the base into the depletion region of the base-collector junction, where the strong electric field collects them. In other words the emitter/base current flow draws some of the barrier charge away from the collector/base junction and allows collector/emitter current to flow across the base using minority carriers. So transistor action is not possible. But we can make transistor by connecting two diodes and two dependent current sources i.e. Ebers-Moll model of transistor. This is true only when you want to make the transistor act like a on/off switch, but you cannot make this setup of diodes to act like an amplifier. Whereas the transistor also acts as an amplifier too A transistor can act as: (1) on/off switch (2) amplifier. Diode is made up of two layers and one junction. Transistor is made up of three layers and two junctions.
Why transistor is called transistor?
Because in this device the resistance between two terminal respectively collector and emitter is changed by changing the base voltage that is it transfers the resistance between emitter and collector therefore it is called as TRANSISTOR. (TRANSFER OF RESISTOR)
Why emitter is heavily doped and base is lightly dopped working of p-n-p transistor?
Emitter is heavily doped because to provide charge carriers to Base & Collector region, Base and Collectors are lightly doped because to accept those charge carriers.
Why a transistor can be operated in active region?
a transistor can only work in active region cox in active region collector base junction is in reverse bias and emitter base junction is in forward bias.
Why is collector region is greater than emitter region?
the collector is where we are getting the the holes or electrons from the emiiter through the base (wrt to the transistor we use). As the carriers are collected there,most heat is dissipited there. so it must be of large size
What is the maximum base thickness in a BJT transistor?
The maximum base thickness in a BJT is dependent on a number of variables and parameters (or call them "constraints"). You could create a base region with thickness ranging from a few layers of atoms up to the point where the "base" region responds to the models of bulk semiconductor by messing with the process parameters. But why? If the base is too thick then with the transistor biased into the 'active' region (i.e., B-E junction forward biased & B-C junction reverse biased), the transistor 'alpha' (the ratio of carriers collected by BC to those generated in BE) will be hopelessly low and the transistor will not exhibit the high current gain that you expect from BJTs. That's because a thick base provides too much opportunity for large numbers of forward current charge carriers to be recaptured by the crystal matrix or lost to the collector current in other ways.
What is cutoff region in transistor?
The cutoff region is when the transistor doesn't have sufficient base current to drive a larger current from emitter to collector. Therefore, the transistor does not turn on and stays shut off.
What arer the 3 legs of a transistor?
Emitter, Collector and Base cutoff region, saturation region, and liner region
What is the difference between the UJT and BJT transistors?
UJT (UniJunction Transistor): It is a transistor with only one junction and three terminals: an emitter (E) and two bases (B1 and B2). BJT (Bipolar Junction Transistor): This type of transistor consists of two junctions and three terminals, namely Emitter "E", Base "B" and Collector"C". There are two types of BJT, i) PNP and ii) NPN.
