Observation of negative bias stressing interface trapping centers　in metal gate hafnium oxide field effect transistors using spin　dependent recombination

摘要

The authors combine metal oxide semiconductor (MOS) gated diode measurements and very sensitive electrically detected electron spin resonance measurements to detect and identify negative bias temperature instability (NBTI) generated defect centers in fully processed HfO_2 pMOS field effect transistors. Both short and long term stressing defects are different from those generated by NBTI in Si/SiO_2 devices. The spectra generated by long term stressing differ from the short term stressing signals and are somewhat similar to those observed in plasma nitrided oxide Si/SiO_2 devices. The results suggest that NBTI defects are located in the interfacial SiO_2 layer of these HfO_2 devices.