Physics II Lab w answers_Part_44 - the straight line Slope = Eg/2k*1000 which yields Eg in eV for the semiconductor material under study(One graph paper

99 the straight line. Slope = E g /2 k *1000 which yields E g in eV for the semiconductor material under study. (One graph paper required) . Reference: D. K. Schroder, “ Semiconductor Material and Device Characterization”, John Willey & Sons Inc. 1990, Chap 1. Appendix: Electrical conductivity of materials The electrical resistance of matter changes with temperature. The number of quasi-free electrons increases with rising temperature which causes the current to increase and the resistance to decrease. On the other hand, the ions of the crystal lattice oscillate more strongly with increasing temperature, thus hindering the electron movement, so that the current decreases and the resistance increases. In conductors (e.g. metals such as Cu, Ag, Al) the second effect dominates, since at room temperature nearly all conduction electrons are quasi-free and contribute to the electron gas. A rise in temperature does not considerably influence their number, so the resistance of metals increases with temperature. Generally this is only a small effect, which can be the other way round