Drift and diffusion in semiconductors

Thread starter dielectrics
Start date Jul 30, 2013
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Diffusion Drift Semiconductors

In summary, drift and diffusion are two important phenomena that occur in semiconductors. Drift refers to the directed movement of charge carriers due to an electric field, while diffusion is the random movement of charge carriers due to concentration gradients. Both drift and diffusion contribute to the overall conductivity of a semiconductor, with drift being more dominant in high electric fields and diffusion being more dominant in low electric fields. The electric field, temperature, and doping concentration all influence the rates of drift and diffusion in semiconductors. Additionally, the mobility of charge carriers directly affects the rates of drift and diffusion, with higher mobility resulting in faster movement and lower mobility resulting in slower movement. These phenomena are observed in many real-world electronic devices, making the understanding and

Jul 30, 2013

dielectrics

Which process occur faster in semiconductors? drift or diffusion

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Aug 2, 2013

dpa2007

http://users.ece.gatech.edu/~alan/ECE3080/Lectures/ECE3080-L-7-Drift - Diffusion Chap 3 Pierret.pdf

Related to Drift and diffusion in semiconductors

1. What is the difference between drift and diffusion in semiconductors?

Drift refers to the movement of charge carriers in a semiconductor due to an electric field, while diffusion refers to the random movement of charge carriers due to concentration gradients. In drift, the charge carriers move in a specific direction, while in diffusion, they move in all directions.

2. How do drift and diffusion affect the conductivity of a semiconductor?

Drift and diffusion both contribute to the overall conductivity of a semiconductor. Drift is more dominant in high electric fields, while diffusion is more dominant in low electric fields. However, at equilibrium, the effects of drift and diffusion cancel each other out, resulting in a constant conductivity.

3. What are the factors that influence drift and diffusion in semiconductors?

The electric field, temperature, and doping concentration are the main factors that influence drift and diffusion in semiconductors. A higher electric field and doping concentration increase the rate of drift, while a higher temperature increases the rate of diffusion.

4. How does the mobility of charge carriers affect drift and diffusion in semiconductors?

The mobility of charge carriers, which is the ability of a charge carrier to move in response to an electric field, directly affects the rates of drift and diffusion. Higher mobility results in faster drift and diffusion, while lower mobility leads to slower rates of drift and diffusion.

5. Can drift and diffusion be observed in real-world devices?

Yes, drift and diffusion play a crucial role in the operation of many electronic devices, such as transistors, diodes, and solar cells. The understanding and control of drift and diffusion are essential for the design and optimization of these devices for various applications.