Semiconductor Diodes

Question 1

What is the Boltzmann’s diode equation?

Answer 1

i=Iₛ(e^qV/nkT^ -1)

Question 2

What is the formula for forward resistance?

Answer 2

R=kT/qi

Question 3

What are the properties of Zener diodes?

Answer 3

•Zener breakdown - happens when high electric field density across the depletion region witch breaks some of the covalent bonds leading to a large number of minority carriers
•Avalanche breakdown - caused by collision. Minority carrier electrons in the depletion region gets accelerated by the reverse biased electric field thereby gaining sufficient kinetic energy to release electron hole pairs from covalent bonds through collusion.

Question 4

Formula for forward resistance of a diode?

Answer 4

R = kT/qi

Question 5

What are the Varactor diode properties?

Answer 5

•produces less noise than other diodes
•cheap
•reliable
•small and light weight
•isn’t useful in forward bias
•increase in reverse bias of Varactor diode increases the capacitance