Characterization of silver-related deep levels in silicon

Abstract
Results from a comprehensive study of silver-related deep levels in silicon are presented. Thermal emission rates and capture cross sections (along with their temperature dependence) for the two dominating Ag-related levels have been measured using deep level transient spectroscopy. For both levels the measured capture cross sections are temperature independent in the investigated temperature range. The activation energies, thus, equal the enthalpies of the corresponding thermal emission processes. Using the same samples photoionization cross sections for electron and hole emission from one of the levels and hole emission from the other have been determined in absolute values using junction photocapacitance measurements. Enthalpies obtained from thermal measurements concur with optical threshold energies to place the two Ag-related levels at EC−0.54 eV and EV+0.34 eV in the band gap of Si.