Thermally stimulated current in SiO2 |
| |
Authors: | D. M. Fleetwood R. A. ReberJr L. C. Riewe P. S. Winokur |
| |
Affiliation: | Sandia National Laboratories, Albuquerque, NM 87185-1083, USA |
| |
Abstract: | Thermally stimulated current (TSC) techniques provide information about oxide-trap charge densities and energy distributions in MOS (metal-oxide-semiconductor) capacitors exposed to ionizing radiation or high-field stress that is difficult or impossible to obtain via standard capacitance–voltage or current–voltage techniques. The precision and reproducibility of measurements through repeated irradiation/TSC cycles on a single capacitor is demonstrated with a radiation-hardened oxide, and small sample-to-sample variations are observed. A small increase in E′δ center density may occur in some non-radiation-hardened oxides during repeated irradiation/TSC measurement cycles. The importance of choosing an appropriate bias to obtain accurate measurements of trapped charge densities and energy distributions is emphasized. A 10 nm deposited oxide with no subsequent annealing above 400°C shows a different trapped-hole energy distribution than thermally grown oxides, but a similar distribution to thermal oxides is found for deposited oxides annealed at higher temperatures. Charge neutralization during switched-bias irradiation is found to occur both because of hole-electron annihilation and increased electron trapping in the near-interfacial SiO2. Limitations in applying TSC to oxides thinner than 5 nm are discussed. |
| |
Keywords: | Thermally stimulated current Radiation effects Oxide reliability MOS devices High-field stress Oxide traps Interface traps Border traps Electron traps Trapped-hole energies Deposited oxides |
本文献已被 ScienceDirect 等数据库收录! |