Deep level transient spectroscopy of hole emission from nitrided oxide/silicon interface traps

The interface hole trap distribution in nitrided oxide (NOX), re-oxidized nitrided oxide (RNOX), and thermal oxide are studied and are compared in detail utilizing the deep level transient spectroscopy (DLTS) measurement. Results show that nitrided oxides have larger amount of hole traps than the thermal oxide. Most of the hole trapping centers in NOX layers are due to the oxygen deficiency as a result of oxygen removal during the nitridation. For RNOX sample, the amount oxygen deficiency centers are reduced by re-oxidation and the non-bridging oxygen could be a major source of hole traps. In addition, we found that the hole emissions of the trapping centers in NOX and RNOX samples also follow the lattice relaxation multiphonon emission model as used in thermal oxide.