Questions tagged [depletion-region]

The **depletion region** (also called **depletion layer** or **depletion zone**) is a spatial region of special properties surrounding a p–n junction when it is turned off. Physics of the depletion region is crucial for understanding properties of a reverse-biased junction.

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Perpetual machine from a PN-junction diode

Consider a PN junction diode Now, this system will naturally form a depletion region due to diffusion and will convert into this: Now, I wish to connect the ends of this diode with a conducting wire ...
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Solve for junction capacitance from diode's SPICE parameters

I am trying to calculate maximum junction capacitance (or depletion capacitance) \$C_j\$ for the BAT62-02L diode from this datasheet based on its SPICE parameters: \$I_s=\$ IS \$=\$ Saturation ...
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Depletion region (space charge region) width calculation

Calculation of depletion region width requires the knowledge of permittivity of the material as shown below. \${\displaystyle w\approx \left[{\frac {2\epsilon _{r}\epsilon _{0}}{q}}\left({\frac {N_{...
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Schottky diodes operation

As far as I know the depletion region is created due to the diffusion of majority charge carriers which expose the charge of their ions. Is this the same for Schottky diodes (electrons diffuse from ...
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Depletion region in metals

Can we create a depletion region (just like in diodes) between two dissimilar metals?What would be the use of that?
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Diode Depletion Region Forces

I'm currently doing some independent research on silicon based devices and I have come up with one question I can't seem to find the answer to elsewhere. I understand that when an n-type and p-type ...
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Drift current in PN Junction

Ok guys, first of all thanks for your support and your help, I can't understand how the drift current work, let's say that we have this junction By the definition of the drift current we can ...
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What happened to Depletion region when biasing is Off after applying reverse biasing?

I was studying Diodes and I came across the information that when the diode is reversed biased the depletion region is increased. Now the depletion region is composed of neutral atoms that are ...
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Where do mobile electrons come from to form an Inversion Layer in an N-MOSFET?

I am trying to understand the concept behind the threshold voltage in a N-MOSFET. Upon reviewing various books and the band diagrams, I analyzed the following but still could not understand where do ...
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Test a battery with diode test

I have just learnt how PN junction work, depletion region etc. And finally I got what actually multimeter's diode test is measuring. If there is potential difference between P and N material, and ...
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Why isn't a depletion region considered at the P-N junction of a MOSFET?

I'm trying to understand the working of an n-channel depletion type MOSFET. I'm confused why no tutorial talks about the depletion region between the P and N type silicon i.e between the 'bulk' and ...
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Pinch off in MOSFETs

as the Vds increases in an NFET, the channel is finally closed and the Id is constant and the channel is saturated When the depletion region around the drain expands and the channel moves mostly to ...
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Model for Diode Shows Voltage Increase not Drop

It's well-known that if a diode is forward biased at a sufficient voltage, there is a voltage drop across the diode, i.e. it dissipates power. However, I was reading Wikipedia's article on the ...
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Why doesn't the depletion zone cover the entire diode?

When you form a PN junction you're basically closing a circuit so why don't the free electrons in the N and the holes in the P diffuse completely as they would in any other circuit?
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Name of diode depletion region voltage

This question is related to an electronic devices course. The unit is on diodes. What do we call the potential difference of the electrical field across the depletion region?
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NMOS Channel Type

I've seen some conflicting information about the inversion channel for an NMOS device. Is NMOS n-channel or p-channel? And is the substrate n or p? I know PMOS is just the opposite for both and the ...
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Depletion Mode MOSFET Modelling in SPICE

Does anyone know how to model a depletion mode N channel MOSFET in spice? I have looked online however the majority of resources have shown how to model a depletion type or enhancement type. I ...
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Diode built-in voltage and barrier voltage (forward bias voltage) are they almost equal? how do they relate to each other?

I am little confused between the built in potential that is built up in the diode depletion region and the barrier voltage that needs to be applied across the PN junction to start conducting. My ...
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Understanding reverse biased PN junction

I'm trying to understand a reverse biased PN junction, conceptually. For reference, I'll adopt the convention that the P-type is on the left, and N-type is on the right. So without a bias, the ...