| Autor: |
Brünger, W.H., Buchmann, L.-M., Naumann, F., Friedrich, D., Finkelstein, W., Mohondro, R. |
| Přispěvatelé: |
Publica |
| Jazyk: |
angličtina |
| Rok vydání: |
1995 |
| Předmět: |
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| Popis: |
Damage in thin (10 nm) oxide layers of metal-oxide-semiconductor varactor cells caused by exposures with ions, electrons, and X-rays has been electrically characterized by constant-current stress time-dependent dielectric breakdown and capacitance-voltage measurements. The time-dependent dielectric breakdown investigations show measurable damage if the ions (H+; 74 keV) are allowed to penetrate the resist (300 nm PMMA) and the poly-Si layer (250 nm) to reach the oxide. This is not the case if the ions (H2+; 74 keV) are stopped inside the poly-Si layer by use of a thicker (450 nm) resist. Also for electrons and X-rays the exposure with lithographic doses did not change the time-dependent dielectric breakdown curves. The capacitance-voltage measurements demonstrate that electrons and X-rays which do penetrate the gate oxide cause a flatband voltage shift of nearly 400 mV. This shift could not be observed if the H2+ ions were stopped in the poly-Si buffer layer. Ions seem to create no sec ondary effects like X-ray generation which reach beyond the penetration depth. The measurements were performed in the unannealed state to detect all possible damage effects including those which can be removed by annealing. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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