The electrical breakdown happens because of Zener or Avalanche.
The PN-junction can be operated in forward-biased conditions and reverse-narrow conditions. In the reverse narrow condition, the current flow happens because of the minority charges.
The Avalanche Breakdown and Zener Breakdown happen in reverse-biased conditions.
Key Takeaways
- Avalanche breakdown occurs at high reverse-bias voltages, while Zener breakdown happens at low reverse-bias voltages.
- Zener breakdown involves quantum tunneling, whereas avalanche breakdown results from the multiplication of charge carriers.
- Avalanche breakdown produces more heat than Zener breakdown, making it less suitable for low-power applications.
Avalanche Breakdown vs Zener Breakdown
Avalanche breakdown occurs through collisions between electrons and atoms in the semiconductor material. Zener breakdown occurs through the tunnelling of electrons through the depletion region of a p-n junction. Avalanche breakdown occurs in high-voltage power devices, unlike Zener.
The Avalanche breakdown occurs in the PN junction. They happen in reverse-biased conditions. The electric field is also weak. It does not have a sharp graph curve. The voltage is greater than 8 volts.
This breakdown Operates in reverse biased condition. In this breakdown, the tunnelling effect does not happen. The electricity connection is destroyed during this breakdown.
The Zener breakdown happens in the Zener diode. They occur in reverse-biased conditions. The electric field is vital. It has a sharp graph curve. The voltage lies between 5 to 8.
This breakdown Operates in reverse biased condition. In this breakdown, the tunnelling effect happens. The electricity connection is not destroyed during this breakdown.
Comparison Table
| Parameters of Comparison | Avalanche Breakdown | Zener Breakdown |
|---|---|---|
| Definition | This breakdown occurs in the P-n junction. | This breakdown happens in the Zener diode. |
| Operates in | This breakdown Operates in reverse biased condition. | This breakdown Operates in reverse biased condition. |
| Voltage | This breakdown has a higher voltage. This breakdown has more than 8. | This breakdown has a lower voltage. This breakdown has volts between 5 to 8. |
| Region | The region is thick. | The region is thin. |
| Electricity connection | The electricity connection is not destroyed during this breakdown. | The field is vital for this breakdown. |
| Electric Field | The field is weak for this breakdown. | The field is strong for this breakdown. |
| Curve | The avalanche breakdown does not have a sharp graph curve. | The Zener breakdown has a sharp graph curve. |
| Temperature Coefficient | The temperature coefficient of the avalanche breakdown is positive. | The temperature coefficient for the Zener breakdown is negative. |
| Doped | The diodes in this breakdown are not highly doped. | The diodes in the Zener breakdown are highly doped. |
What is Avalanche Breakdown?
Avalanche breakdown happens in a P-n junction diode. This breakdown occurs when a high voltage is applied to the diode. This breakdown Operates in reverse biased condition.
For this breakdown, the electric field is weak.
The electricity field is calculated using the Ea =Va/d formula, where Va is the reverse voltage and d is the layer’s width. The diodes in this breakdown are not highly doped.
When the voltage that is applied reaches the breakdown region, the charge carriers collide with the present atoms, generating the collision of the two free electrons.
These two electrons then collide with others,, resulting in two more free electrons. This process then continues, which results in a drastic increase in the charge carriers.
This makes a jump to the reverse saturation current. This effect is called the Avalanche breakdown.
This breakdown effect results in impact ionization. This breakdown Operates in reverse biased condition. The electricity connection is destroyed during this breakdown.
The temperature coefficient of the avalanche breakdown is positive.
This effect or breakdown happens with a high reverse voltage in an electric field. The electricity connection is destroyed during this breakdown. This breakdown has more than 8.
What is Zener Breakdown?
The Zener breakdown happens in an electric field with the PN junction diode. This breakdown Operates in reverse biased condition. This then results in the free electrons in the electric field.
For this breakdown, the electric field is vital.
Zener diode is a type of PN junction diode which operates in reverse-biased conditions. The diodes in the Zener breakdown are highly doped.
The Zener diode has a higher number of impure atoms in comparison with the PN junction. Due to this, the Zener diode has many free particles. The free electrons are the charge carriers.
Due to this, many free electrons are created, which results in the reverse saturation current. This breakdown has volts between 5 to 8. The temperature coefficient for the Zener breakdown is negative.
This breakdown is called the Zener effect breakdown. In this, the field becomes strong, restricting the charge carriers from accelerating or moving from one place to another.
The electricity connection is not destroyed during this breakdown.
Main Differences Between Avalanche Breakdown and Zener Breakdown
- The Zener breakdown happens at a lower voltage than the avalanche breakdown.
- The Zener breakdown volts lie between 5 to 8, while the avalanche breakdown has higher than 8 volts.
- The temperature coefficient of the avalanche breakdown is positive, whereas, for the Zener breakdown, the temperature coefficient is negative.
- The diodes in the Zener breakdown are highly doped, whereas those in the avalanche breakdown are lightly doped.
- The avalanche breakdown doesn’t have a sharp graph curve, whereas the Zener breakdown has a sharp graph curve.
- The voltage is not affected for the Zener breakdown, whereas the voltage is affected and may vary for the avalanche breakdown.
- https://journals.aps.org/pr/abstract/10.1103/PhysRev.99.1234
- https://journals.aps.org/pr/abstract/10.1103/PhysRev.102.369
Last Updated : 06 July, 2023
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Piyush Yadav has spent the past 25 years working as a physicist in the local community. He is a physicist passionate about making science more accessible to our readers. He holds a BSc in Natural Sciences and Post Graduate Diploma in Environmental Science. You can read more about him on his bio page.
Great article, it provides a comprehensive understanding of the Zener and Avalanche breakdown. I found the comparison table particularly insightful.
This article is a brilliant blend of scientific rigor and accessible language. The detailed explanations and comparison table make it an invaluable resource for anyone interested in understanding Zener and Avalanche breakdown.
The explanation of the Zener and Avalanche breakdown was very thorough and well-researched. The article does a great job of simplifying complex concepts for readers without sacrificing depth or accuracy.
A very informative and thorough explanation on the subject of Zener and Avalanche breakdown. The explanation of the differences and how each breakdown occurs is very detailed and helpful.
This article is very biased and only describes the positive aspects of the Zener breakdown while downplaying the importance of the Avalanche breakdown. A more balanced view would have been appreciated.
This detailed comparison of Avalanche and Zener breakdown is very helpful in understanding the fundamental differences between the two phenomena. The inclusion of key takeaways and references lends credibility to the article.