Difference between Zener Breakdown and Avalanche Breakdown

Difference between Zener Breakdown and Avalanche Breakdown:

The difference between Zener Breakdown and Avalanche Breakdown is given in table below

Zener Breakdown	Avalanche Breakdown
This is observed in zener diodes having reverse voltage of less than 5 volts.	This is observed in zener diodes having reverse voltage of 5 or more volts.
The valance electrons are pulled into conduction band due to very intense electric field appearing across the narrow depletion region.	The valence bands are pushed into conduction band due to the energy imparted by colliding accelerated minority carriers.
The breakdown voltage decreases with the increase in temperature i.e. temperature coefficient is negative.	The breakdown voltage increases with the increase in temperature i.e. temperature coefficient is positive.
V-I characteristics with the zener breakdown are very sharp.	V-I characteristics with the avalanche breakdown rise gradually. It is not as sharp as that with the zener breakdown.