Question

uestion#1 Show that the local resistivity p of the semiconductor is given by, where the conductivity of electron and hole are ơn and ơp respectively, which are given by, Where q is the elementary charge, n and p are the local electron and hole concentration respectively, and un and pp are local electron and hole mobility respectively. In addition, explain why the contribution from one type of carrier can always been ignored under equilibrium condition. Hint: you can carry out the proof in ID case. Quesiton#2 A voltmeter is attached to a piece of silicon, and a heat source is placed on one of the probes. The non-heated probe has a positive reading. What is the doping type of the silicon and why? Question#3 To be posted...

PLEASE JUST TO THE CONCEPTUAL PART OF THE QUESTION 1. ((I DO NOT NEED THE DERIVATION)). PLEASE DO NUMBER 2 AS WELL.

THESE SHOULDNT TAKE LONG, I JUST NEED SOME CONTEXT.

THANKS IN ADVANCE

Answer 1

1. In equilibrium we assume that the no. of positive and negative charge carriers are equal which implies that in the expression above we can use only one of the charge carriers which results in the neglegance of the other.

2. The doping must be a pentavalent impurity as the non heated probe is at higher potential which implies that electron flow will take place from non heated probe to the heated probe which means there will be high concentration of negatively charged particles.