Conceptual Questions
1.) True or False: At any temperature, the Fermi energy is the energy level above which all electron states are empty.
2.) (Based on Serway/Jewett - Objective Question 43.5). The conductivity of metals decreases with increasing temperature due the increased frequency of electron collisions with atoms. In contrast the conductivity of intrinsic semiconductors increases as T increases. What property of a semiconductor is responsible for this behavior?
(a) Collisions decrease as the temperature increases
(b) The number of free electrons and holes increases steeply with T
(c) The energy gap decreases with increasing temperature
(d) Electrons do not collide with atoms in a semiconductor