IMPURITY RESISTIVITY IN DOUBLY DELTA-DOPED SYSTEMS

We present an expression for the impurity resistivity for a general nu mber of subbands in singly and doubly delta-doped structures. The true wave functions of the carriers and the intraband scattering from inte raction between carriers of different bands are considered. The calcul ations are performed within the generalized Drude approach and with th e temperature dependent RPA screening matrix. Numerical results for ge neral temperatures are presented for singly n-doped Si and doubly n-do ped Si with varying distance between the doped layers. We propose an e xplanation for the observed enhancement of the mobility in doubly delt a-doped structures, as compared to singly delta-doped systems.