Unformatted text preview: angstrom. What is the Fermi level at 0 K? What is the probability of exciting a carrier to the first excited state at T=300 K? Use the free electron mass in this problem. 4. A Si sample doped with 10 17 As atoms/cm 3 , (a) What is the equilibrium hole concentration p o at 300 K? (b) Where is E F relative to E i ? (c) Is the semiconductor degenerate or non-degenerate? Why? (d) An electric field E = 1 V/cm is applied to the semiconductor. Draw the band diagram (Ec, Ev, and Ei) and indicate the directions of electron and hole flow. In what direction will the total electric current flow? (e) If the average time between collisions is 1 ps, what will be the electron and hole mobilities? (f) Calculate the total drift current density. Assume the same collision time for holes....
View Full Document
- Spring '09
- Electron, Electric charge, Fundamental physics concepts, free electron mass, electron rest mass