Understanding Schottky Barrier Height: Why the Energy Bands?

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In summary, the conversation discusses the Schottky-Mott theory of Schottky Barrier height and questions why the energy bands on the semiconductor side at the interface are assumed to be the same as the ones of the isolated semiconductor. The question also questions why the electronic affinity is assumed to be the same at the interface and the bulk of the semiconductor. The deduction is based on fundamental thermodynamical principles but the reasoning behind the assumption is not clear.
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Fernsanz
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I have been chewing up some time ago the Schottky-Mott theory of Schottky Barrier height (which ignores the surface states). All the deduction seems to ground on fundamental thermodynamical principles (as the equality of Fermi levels- i.e. equality of chemical potential in equilibrium) but there is something which I can't clearly see and is one of the key points to calculate the height barrier: Why the energy bands on the semiconductor side just at the interface are assumed to be the same that the ones of the isolated semiconductor? It is clear that the band have to bend (because of the electric field) but I see no reason to why the bands values should "start" to bend from the original values (the values of the isolated semiconductor).

To put it in other words, the question could be restated: why the electronic affinity is assumed to be the same at the interface than at the bulk of the semiconductor?


Thanks.
 
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I'm sorry you are not generating any responses at the moment. Is there any additional information you can share with us? Any new findings?
 

FAQ: Understanding Schottky Barrier Height: Why the Energy Bands?

1. What is a Schottky barrier?

A Schottky barrier is a type of energy barrier that forms at the interface between a metal and a semiconductor. It is caused by the difference in work function between the two materials, which creates a potential barrier that impedes the flow of electrons.

2. How is the Schottky barrier height determined?

The Schottky barrier height is determined by measuring the difference in energy between the Fermi level of the metal and the conduction band edge of the semiconductor. This can be done using techniques such as capacitance-voltage measurements or photoemission spectroscopy.

3. What factors influence the Schottky barrier height?

The Schottky barrier height is influenced by several factors, including the work function of the metal, the band gap of the semiconductor, and the interface quality between the two materials. Other factors such as temperature and doping concentration can also affect the barrier height.

4. Why is understanding the Schottky barrier height important?

Understanding the Schottky barrier height is important for the design and performance of electronic devices. It affects the junction properties and can impact the device's efficiency and reliability. Additionally, it is an important parameter for the development of new materials and technologies.

5. How does the Schottky barrier height affect device performance?

The Schottky barrier height affects device performance in several ways. A higher barrier height can result in lower leakage currents and better rectifying behavior, while a lower barrier height can lead to increased tunneling and reduced device efficiency. Additionally, changes in the barrier height can affect the device's response to external stimuli such as temperature and light.

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