Question

The cut off voltage for diode of silicon semiconductor and germanium semiconductor is ____ volts.

(a) 0.5 and 0.1

(b) 0.7 and 0.3

(c) 1 and 0.5

(d) 0.5 and 1

The question was asked during a job interview.

Question is taken from The Volt Ampere Characteristics topic in portion Semiconductor-Diode Characteristics of Electronic Devices & Circuits

Answer 1

Right answer is (b) 0.7 and 0.3

Easy explanation: The cut off voltage is the voltage only after which the semiconductors conduct, the cut off voltage for silicon is 0.7V in the sense the silicon diode will conduct only when voltage is more than 0.7V and 0.3 for germanium.