# hw2s - Question 1 For silicon germanium and gallium...

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

Question 1. For silicon, germanium and gallium arsenide, calculate from the effective mass for density of states calculations (Appendix 3) the effective densities of states in the conduction and valence band, and from those calculate the intrinsic carrier density. (assume T = 300K). a) List the calculated values in a table together with the values from Appendix 3 as shown below: The effective densities of states are obtained from 2 / 3 2 * ] 2 [ 2 h kT m N e c and 2 / 3 2 * ] 2 [ 2 h kT m N h v While the intrinsic carrier density is obtained from kT E v c i g e N N n 2 / Using the bandgap and effective mass for density of states calculations listed below: Name Symbol Germanium Silicon GaAs Bandgap energy at 300 K E g (eV) 0.66 1.12 1.424 Effective mass for density of states calculations Electrons m e * / m 0 0.55 1.08 0.067 Holes m h * / m 0 0.37 0.81 0.45 one finds the following results: T = 300K Germanium Silicon GaAs Calculated From App. 3 Calculated From App. 3 Calculated From App. 3 N c (cm -3 ) 1.02 x 10

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.

## This note was uploaded on 11/07/2011 for the course ECEN 5355 at Colorado.

### Page1 / 3

hw2s - Question 1 For silicon germanium and gallium...

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

View Full Document
Ask a homework question - tutors are online