Measurements of Hydrogen Redistribution in Hot Electron Injection of Mos Capacitors

ABSTRACTRedistribution of hydrogen caused by hot electron injection has been studied in large Al-gate capacitors using internal photemission followed by hydrogen depth profiling with the 15 N nuclear reaction. A large peak of hydrogen (∼ 1015 at /cm2) at the Al/SiO2 interface due to a hydrated layer on the surface of the SiO2 was found to act as a source of hydrogen during the photoinjection. A small fraction of the hydrogen released from this peak was found to be re-trapped near the Si/;SiO2 interface if a field of >1 MV/cm was applied to the SiO2 during the injection. Up to 2 × 1014 atoms/cm2 of hydrogen were found to be trapped at this interface for injected fluences up to 5 C/cm2. These results are discussed in terms of current models of interface state generation involving hydrogen.