| AVS 60th International Symposium and Exhibition | |
| Surface Science | Tuesday Sessions |
| Session SS-TuP |
| Session: | Surface Science Poster Session |
| Presenter: | R. Shyam, Clemson University |
| Authors: | R. Shyam, Clemson University E. Srinadhu, Clemson University J.E. Harriss, Clemson University W.R. Harrell, Clemson University C.E. Sosolik, Clemson University |
| Correspondent: | Click to Email |
As-grown SiO2 layers (50 nm to 200 nm) were exposed to incident beam of Na+ ions with energies in the range of 100 eV to 10 keV. The oxide is analyzed post exposure by encapsulating the irradiated and pristine region under top metallic (Aluminum) contacts or within a finished MOS device. Characterization of the resulting ion-modified and pristine MOS devices involves the standard techniques of bias-temperature stress and high and low frequency capacitance-voltage (C-V) measurements. Our high frequency C-V data show flatband voltage shifts and changes in slope of the irradiated devices that are beam energy dependent. The flatband voltage shifts are greater than those expected for mobile charges only, implying an irradiation-dependent effect. Additionally, the interface trap density, extracted from the high and low frequency C-V measurements, increases by one order of magnitude over our incident beam energy. We model these effects with standard formalisms for MOS capacitance in the presence of interface defects, where SRIM is used to include ion implantation depth and damage within the oxide.