Semiconductor Devices

The forbidden energy gap for Silicon is of the order of

• 0.7 eV

• 0.3 eV

• 1.1 eV

• 10 eV

Which of the following acts as a donor impurity in doping process ?

• Arsenic

• Indium

• Gallium

• Boron

The reverse saturation current in a PN Junction diode is only due to _________________.

• minority carriers

• majority carries

• negative ions

• positive ions

Which of the following is a symbol of NPN transistor ?

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• 
• 
• 

Conductivity of semiconductor __________________ with increase in temperature.

• increases

• decreases

• remains unchanged

Name this electronic component

• Capacitor
• Fixed Resistor
• Potentiometer
• Transistor

This is a graph that is seen on CRO. How is it change after full wave rectification process?

• 
• 
• 
• 

LED is

• Light Enhancing Diode

• Light Emitting Diode

• Light Emitting Detector

• Light Enhancing Detector

The energy band in which free electrons exist is know as

• first band

• second band

• conductive band

• valence band

Let n_p and n_e be the number density of holes and electrons respectively in a pure semiconductor. Then,

• n_p < n_e

• n_p= n_e

• n_p > n_e

• none of above