Abstract

To clarify the generation mechanism of radiation damage induced in SiO2/Si by plasma processes, the effects of four different particles, i.e., ions, electrons, neutrals and vacuum ultraviolet (VUV) photons have been evaluated independently. The radiation damage caused by these energetic bombardments has been measured by C-V method. This study revealed that the bombardments with neutral beams generate far less flat-band boltage shifts (δ VFB) than those with ion beams of the same kinetic energy. This is interpreted in terms of the differences in hole production yield and charge build-up upon the incidence of these particles. VUV photons produced in the plasma are also responsible for large δ VFB. This kind of damage is critically dependent on the hole transport from the SiO2 surface to the SiO2/Si interface and it is found that the amount of damage is greatly reduced by keeping the specimen at lower temperatures. Finally, it was found that low-energy electron bombardments generate large δVFB via plasmon excitations in SiO2.