LOCALIZED STATES AND CONDUCTIVITY IN SILICON AMORPHIZED BY ION-IMPLANTATION

Taking into account the connection between spin density and gap state density in amorphous silicon (a‐Si), the EPR data are evisaged aimed at controlling the density of localized states with different radiation and heat treatment of Si amorphized by ion implantation. Results are considered on thermal annealing of ion‐implanted Si layers, the interaction between hydrogen and dangling bonds which are responsible for localized states in a‐Si, as well as the interaction between transition elements (Cr, Mn, Cu, and Zn) and dangling bonds. The data on combined irradiation are considered too: firstly the group III or V ion implantation is performed to Si (or a‐Si) and then the electron beam irradiation conducted. Some ways of doping a‐Si are discussed. One of the ways consists in the group III or V ion implantation to high doses (> 1016 cm−2). The other way is the combined irradiation of a‐Si. Copyright © 1979 WILEY‐VCH Verlag GmbH & Co. KGaA