Semiconductor, Diode and Rectification

A semiconductor is formed by ……… bonds.

• Covalent

• Electrovalent

• Strength

• Co-ordinate

Addition of trivalent impurity to a semiconductor creates many …….

• Bound electrons

• Free electrons

• Holes

• Valence electrons

A semiconductor has ………… temperature coefficient of resistance.

• Positive and Negative

• Zero 

• Positive

• Negative

A pentavalent impurity has ………. valence electrons

• 3

• 4

• 5

• 6

When a pure semiconductor is heated, its resistance …………..

• Goes Up

• Goes Down

• Fluctuated

• Remains the same

The barrier voltage at a PN junction for silicon is about ………

• Zero

• 0.5V

• 0.3V

• 0.7V

With forward bias to a PN junction , the width of depletion region ………

• Decreases

• Increases

• Remains the same

• Fluctuate

A diode is in forward biased when

• For a diode, the number of minority carriers crossing the junction mainly depends on supply

• Positive terminal of the battery is connected to N-side and the negative side to the P-side

• Positive terminal of the battery is connected to P-side and the negative side to the N-side  

• N-side is connected directly to the p-side

Holes in N-type semiconductor is

• minority carriers that are thermally produced

• minority carriers that are produced by doping

• majority carriers that are thermally produced

• majority carriers that are produced by doping

In reverse bias, the width of the depletion region in a diode:

• Decreases

• Remains the same

• Increases

• Oscillates