Why is leakage current less in silicon?
Leakage current is less in silicon made devices than germanium made since its energy bandgap is more than that of germanium.
Why is silicon more stable than germanium?
The PIV rating determines how much resistance a diode can make before breakthrough V (s) The forbidden energy band of silicon is 1.1ev and thus higher than that of germanium (0.66ev), which makes silicon more stable and reduces the leakage current.
Which diode has more leakage current silicon or germanium?
Silicon diodes have a greater ease of processing, lower cost, greater power handling, less leakage and more stable temperature characteristics than germanium diodes. Germanium diodes’ lower forward drop (. 2V to .
Why Zener diode is highly doped?
Zener diode is heavily doped than the normal p-n junction diode. Hence, it has very thin depletion region. But while in reverse bias their junction potential is increased. So that means when the voltage crosses 6V then the diode is in Reverse breakdown and hence the current through the diode increases rapidly.
What is avalanche breakdown and Zener breakdown?
Hint: There are two types of breakdowns in p-n junctions. Avalanche breakdown occurs due to the rapid collision of electrons with other atoms. Zener breakdown occurs because of the high electric field. Zener breakdown is the controlled version of Avalanche breakdown in a modified p-n junction.
What is the difference between thermal breakdown and Zener breakdown?
The avalanche breakdown produces the pairs of electrons and holes because of the thermal effects, whereas the Zener diode produces the electrons. The avalanche breakdown occurs in low doping material, whereas the Zener breakdown occurs in high doping material.
What is Zener break down voltage?
The Zener Breakdown is observed in the Zener diodes having Vz less than 5V or between 5 to 8 volts. When a reverse voltage is applied to a Zener diode, it causes a very intense electric field to appear across a narrow depletion region.
What is meant by Zener breakdown voltage?
When reverse biased voltage applied to the zener diode reaches zener voltage, it starts allowing large amount of electric current. At this point, a small increase in reverse voltage will rapidly increases the electric current. Because of this sudden rise in electric current, breakdown occurs called zener breakdown.
What is the difference between Zener and avalanche breakdown voltage?
Zener Breakdown vs Avalanche 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.
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).