1. describe with the aid of simple sketches, how a hole appears to move in a semiconductor 2. how does an increase in the temperature of a

1. describe with the aid of simple sketches, how a hole appears to move in a semiconductor

2. how does an increase in the temperature of a semiconductor material affects its intrinsic conduction? the resistivity of silicon is 2300 ohmsmetres at 27 degree centigrade. what will be its resistivity if the temperature is increased by (i) 10% and (ii) 25%? Assume that the intrinsic conductivity of silicon increased by 7% per degree centigrade increased in temperature

3. explain clearly, why the current flowing across a p-n junction is the sum of the soles and the electron current flowing across the junction. in which direction does the election current flow?

4. explain why the resistance of a conductor increases with temperature but the resistance of a semiconductor decreases. briefly explain how an intrinsic semiconductor material can be made into either n-type or a p-type extrinsic semiconductor. what is meant by majority charge carrier and minority charge carriers in a p-type region

5. explain why a p-n junction possesses capacitance. is the capacitance increased or decreased when the reversed bias is reduced?

6. in p-type semiconductor material holes are present in much greater number than electrons. why therefore is the semiconductor electrically neutral?

7. (a) how does a trivalent impurity modify an intrinsic semiconductor? (b) how does a pentavalent impurity modify an intrinsic semiconductor