How to find barrier potential of pn junction diode

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Discussion Overview

The discussion centers on the theoretical determination of the barrier potential in a pn junction diode, including inquiries about the relationship between barrier potential and energy band gap. The scope includes theoretical concepts and practical implications related to semiconductor physics.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant seeks clarity on how to theoretically determine the barrier potential when a pn junction diode is formed, questioning the relationship between barrier potential and energy band gap.
  • Another participant notes that the energy gap does not have an explicit dependence on the potential barrier, attributing the potential barrier to the difference in Fermi energy between p-type and n-type semiconductors.
  • Further inquiries are made about practical methods for determining barrier potential and whether theoretical calculations can be initiated from the band structure of the semiconductors involved.
  • There is a suggestion that examining the Fermi energy values could provide a straightforward method for determining the barrier potential, though this approach is questioned as potentially too simplistic.

Areas of Agreement / Disagreement

Participants express differing views on the clarity of the theoretical determination of barrier potential and the relationship with energy band gap, indicating that the discussion remains unresolved with multiple perspectives presented.

Contextual Notes

The discussion highlights uncertainties regarding the definitions and assumptions related to barrier potential and energy band gap, as well as the methods for theoretical calculation versus practical measurement.

physics.cie
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I want to know that when a pn junction diode is formed and barrier potential is setup then how can we determine the same theoretically. Also I wan to know that is there any relation between barrier potential and energy band gapSmall band gap small barrier? ?
 
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Any 1here to help me out of this.
 
physics.cie said:
I want to know that when a pn junction diode is formed and barrier potential is setup then how can we determine the same theoretically. Also I wan to know that is there any relation between barrier potential and energy band gap


Small band gap small barrier? ?

The first part of your question isn't clear. What do you mean by "can we determine the same theoretically"? What are you trying to determine theoretically?

The energy gap has no explicit dependence on the potential barrier. The potential barrier is due to the difference in the Fermi energy of the p and n-type semiconductor.

Zz.
 
Ok,bt when pn junction diode is formed then barrier potential is setup which can be determined practically, is thr any way to find barrier potential theoritically?
 
physics.cie said:
Ok,bt when pn junction diode is formed then barrier potential is setup which can be determined practically, is thr any way to find barrier potential theoritically?

Starting from where? From the calculation of the band structure for each of the semiconductor?

Why can't you just look at the different values of the Fermi energy and then... hum... just find the difference between the two? Or is this too simple to count as "theoretical"?

Zz.
 

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