Oxide, interface, and border traps in thermal, N{sub 2}O, and N{sub 2}O-nitrided oxides
- Sandia National Laboratories, Department 1332, Albuquerque, New Mexico 87185-1083 (United States)
- Naval Research Laboratory, Washington, DC 20375 (United States)
We have combined thermally stimulated-current (TSC) and capacitance{endash}voltage ({ital C}{endash}{ital V}) measurements to estimate oxide, interface, and effective border trap densities in 6{endash}23 nm thermal, N{sub 2}O, and N{sub 2}O-nitrided oxides exposed to ionizing radiation or high-field electron injection. Defect densities depend strongly on oxide processing, but radiation exposure and moderate high-field stress lead to similar trapped hole peak thermal energy distributions (between {approximately}1.7 and {approximately}2.0 eV) for all processes. This suggests that similar defects dominate the oxide charge trapping properties in these devices. Radiation-induced hole and interface trap generation efficiencies (0.1{percent}{endash}1{percent}) in the best N{sub 2}O and N{sub 2}O-nitrided oxides are comparable to the best radiation hardened oxides in the literature. After {approximately}10 Mrad(SiO{sub 2}) x-ray irradiation or {approximately}10 mC/cm{sup 2} constant current Fowler{endash}Nordheim injection, effective border trap densities as high as {approximately}5{times}10{sup 11} cm{sup {minus}2} are inferred from {ital C}{endash}{ital V} hysteresis. These measurements suggest irradiation and high-field stress cause similar border trap energy distributions. In each case, even higher densities of compensating trapped electrons in the oxides (up to 2{times}10{sup 12} cm{sup {minus}2}) are inferred from combined TSC and {ital C}{endash}{ital V} measurements. These trapped electrons prevent conventional {ital C}{endash}{ital V} methods from providing accurate estimates of the total oxide trap charge density in many irradiation or high-field stress studies. Fewer compensating electrons per trapped hole ({approximately}26{percent}{plus_minus}5{percent}) are found for irradiation of N{sub 2}O and N{sub 2}O-nitrided oxides than for thermal oxides ({approximately}46{percent}{plus_minus}7{percent}). (Abstract Truncated)
- Research Organization:
- Sandia National Laboratory
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 277187
- Journal Information:
- Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 3 Vol. 79; ISSN JAPIAU; ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Thermally stimulated current measurements of SiO sub 2 defect density and energy in irradiated metal-oxide-semiconductor capacitors
Physical mechanisms contributing to enhanced bipolar gain degradation at low dose rates