C-V hysteresis instability in aluminum/tantalum oxide/silicon oxide/silicon capacitors due to postmetallization annealing and Co-60 irradiation
Journal
Journal of the Electrochemical Society
Journal Volume
135
Journal Issue
11
Pages
2808-2813
Date Issued
1988
Author(s)
Abstract
The C‐V hysteresis instability in the capacitors consisting of tantalum oxide layers was studied by postmetallization annealing at various temperatures below 400°C and by Co‐60 irradiation with a total dose of . It was found that the directions of the C‐V hysteresis loops of an aluminum/tantalum oxide/silicon oxide/silicon(n) capacitor can be changed from counterclockwise to clockwise when the annealing temperature varies from 200° to 400°C gradually. After receiving a Co‐60 irradiation, the C‐V hysteresis loops of the samples under testing became much larger under the same measurement condition. A model consisting of the leakage property of tantalum oxide and the generation of slow trap states at the silicon oxide/silicon interface due to negative charge‐temperature effect was proposed in this work, and explained the observations quite well.
Type
journal article