Why is silicon the most used semiconductor?
Silicon, a very common element, is used as the raw material of semiconductors because of its stable structure. Purification of Silicon consumes large amounts of power. In Japan, refined Silicon (ingot) with purity of at least 98% is imported from Australia, China and Brazil, where electricity is relatively inexpensive.
Why is silicon is more widely used in electronic industries compared to germanium?
Silicon Structure The physical properties of Silicon also contribute to its popularity and usage as a semiconductor material. Silicon possesses a moderate energy band gap of 1.12eV at 0 K. This makes silicon a stable element when compared to Germanium and reduces the chance of leakage current.
What is meant by Zener breakdown?
Valence electrons which break free under the influence of the applied electric field can be accelerated enough that they can knock loose other electrons and the subsequent collisions quickly become an avalanche. This process of sudden release of electrons is known as zener breakdown.
What is the main cause of Zener breakdown?
The main cause of zener breakdown is high doping concentrations. For heavily doped junctions, when reverse voltage is increased, the electric field at junction increases (as more carriers are present now to create such a pull) which causes covalent bonds to break.
What are the advantages of Zener diode?
Advantages of Zener Diodes
- Less expensive than other diodes.
- Ability to shift voltage.
- Easily compatible and obtainable across systems.
- High-performance standard.
- Protection from over-voltage.
- Ability to regulate and stabilize circuit voltage.
- Greater control overflowing current.
- Usable in smaller circuits.
What is the main difference between avalanche and Zener breakdown?
The main difference between Zener breakdown and avalanche breakdown is their mechanism of occurrence. Zener breakdown occurs because of the high electric field whereas, the avalanche breakdown occurs because of the collision of free electrons with atoms. Both these breakdowns can occur simultaneously.
What are types of breakdown in zener diode?
A zener diode has two distinctly different breakdown mechanisms: zener breakdown and avalanche breakdown. The zener breakdown voltage decreases as the temperature increases, creating a negative temperature coefficient (TC). The avalanche breakdown voltage increases with temperature (positive TC) (Pryce, 1990).
What is breakdown and its types?
Different Types Of Break down Diodes mainly includes Signal diode, Zener diode, Tunnel diode, Gunn diode, Crystal diode, Varactor diode, Constant current diode, Light emitting diode, IR leds, Schottky diode, PIN diodes, Avalanche diode, Laser diode, Shockley diode, Photodiodes, Transient Voltage suppression diode.
Is Zener breakdown reversible?
Avalanche breakdown is not reversible while Zener breakdown is reversible. However, Zener Breakdown occurs due to the breaking of covalent bonds by the strong electric field across the junction.
Which breakdown is a reversible process?
A Zener breakdown in the Zener diode will not damage the diode; while on the other hand, Avalanche breakdown will damage the diode completely. Thus, Zener breakdown could be re-achieved (hence reversible) while Avalanche breakdown couldn’t be.
What is reverse bias?
reverse bias The applied d.c. voltage that prevents or greatly reduces current flow in a diode, transistor, etc. For example, a negligible current will flow through a diode when its cathode is made more positive than its anode; the diode is then said to be reverse biased.