# HW3 - , , and the position of the Fermi level with respect...

This preview shows pages 1–2. Sign up to view the full content.

Georgia Institute of Technology School of Electrical and Computer Engineering ECE 3040A Microelectronic Circuits Homework 3 Due: Friday, 09/12/2008 in class 1. band and holes in the valance band have peaks very close to the band edges . In this problem, we get a quantitative idea about how close to the band edges these peaks are. (Pierret 2.7 and 2.8) 25 points a. In a nondegenerate seminconductor , show that the distribution of the number of electrons in the conduction band has a peak at . Where is the corresponding peak for the distribution of the number of holes in the valance band? b. What is the ratio of the electron population at to the peak electron population? 2. In a sample, near room temperature (300 ), it is known that , and , and . Determine, , , and the position of the Fermi level with respect to . Is this sample type or type? 25 points 3. For each one of the following samples, determine

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: , , and the position of the Fermi level with respect to . Specify whether the sample type or type? 25 points a. A sample at doped with Boron atoms. b. A sample at doped with atoms. c. A sample at doped with Boron atoms and As atoms. 4. Derive an expression relation the intrinsic level to the center of the bandgap . Calculate the displacement of to from for at . Assume that for at this temperature , and . 25 points We know that if the Fermi energy is at the center of the bandgap, the Fermi functions in the valance band and the condition band are the same. We also know that for an intrinsic semiconductor . Having this in mind, can you Georgia Institute of Technology School of Electrical and Computer Engineering ECE 3040A Microelectronic Circuits explain why (the Fermi level for an intrinsic semiconductor) is not at the center of the bandgap? 10 extra points...
View Full Document

## This note was uploaded on 01/17/2011 for the course ECE 3040 taught by Professor Hamblen during the Fall '07 term at Georgia Institute of Technology.

### Page1 / 2

HW3 - , , and the position of the Fermi level with respect...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online