(k) Assuming a hole carrier density of states of the form 1 2mn Dp (E) * F.B}} (E, – 272 ħ2 and by first making an appro
Posted: Wed Mar 09, 2022 9:16 am
(k) Assuming a hole carrier density of states of the form 1 2mn Dp (E) * F.B}} (E, – 272 ħ2 and by first making an appropriate approximation of the Fermi-Dirac distribution, derive an expression for the hole concentration p as a function of the temperature and the Fermi level. Explain your answer on physical grounds. The symbols take their usual meanings. [3 marks] (1) State one definition, with the aid of its equation, of the effective masses of electrons and holes in terms of the features of a band-structure, and explain its meaning. Define precisely the distinction between a direct gap semiconductor and an indirect gap semiconductor. [1 mark]