Comparative Study of Charge Trapping in High-Dose Si and Ge-Implanted Al / SiO2 / Si Structures

Abstract

We have studied the trapping of negative and positive charge in Si-implanted layers of -based devices during high-field electron injection from the Si substrate under conditions typically used for obtaining electroluminescence. The location, capture cross section, and concentration of negatively and positively charged traps are determined in dependence on the time of heat-treatment by rapid thermal annealing (RTA). A comparison between the results obtained from Si- and Ge-implanted oxide layers is made. It is shown that in the case of Si-rich oxides an increase in the RTA time leads to the formation of hole and electron traps of high concentration, both of which are located within the oxide. For Ge-rich oxide layers, however, the hole traps are found primarily in the vicinity of the interface while the electron traps are present within the oxide. The nature of these traps is discussed. © 2004 The Electrochemical Society. All rights reserved.