Distinguish between zener breakdown and Avalanche breakdown.

Zener breakdown :
1) This occurs in heavily doped diodes
2) This occurs at low reverse bias voltages
3) The thickness of depletion layer is less than one micron
4) This occurs in zener diodes
5) Due to strong electric field, rupture of covalent bonds takes place.
Avalanche break down :
1) This occurs in lightly doped diodes
2) This occurs at high reverse bias voltages
3) The thickness of depletion layer is of the order of one micron
4) This occurs in general diodes
5) Due to sufficient electric field , disturbing of covalent bonds takes place