Loading…
Model for the current–voltage characteristics of ultrathin gate oxides after soft breakdown
The current–voltage characteristics of metal-oxide-semiconductor capacitors with a 4.2 nm SiO2 gate oxide are investigated. After the occurrence of soft breakdown, which is observed during constant current stress of the devices, the gate current is shown to behave like a power law of the applied gat...
Saved in:
Published in: | Journal of applied physics 1998-10, Vol.84 (8), p.4351-4355 |
---|---|
Main Authors: | , , , |
Format: | Article |
Language: | English |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | The current–voltage characteristics of metal-oxide-semiconductor capacitors with a 4.2 nm SiO2 gate oxide are investigated. After the occurrence of soft breakdown, which is observed during constant current stress of the devices, the gate current is shown to behave like a power law of the applied gate voltage. We propose that this power law behavior is due to the formation of a percolation path between the electrons traps generated in the SiO2 layer during current stress of the capacitor. We describe a simple model which accounts for the current–voltage characteristics between two neighbor trapping sites, as well as a distribution of percolation thresholds in these (finite size) ultrathin SiO2 layers. The prediction of the model is in fair agreement with the experimental results in a large voltage range, and leads to a better description of the data than previously reported models. Furthermore, it is shown that this percolation model can also explain the temperature dependence of the gate current after the occurrence of soft breakdown. |
---|---|
ISSN: | 0021-8979 1089-7550 |
DOI: | 10.1063/1.368654 |