F contamination effects on intrinsic and extrinsic gate oxide reliability

The subject of this work is the study of the effect of fluorine contaminants on the intrinsic and extrinsic gate oxide reliability. After a brief introduction in which the author explains the known effects of fluorine contaminants on the oxide quality, the the test structures used in this work to separate the effect of fluorine contaminants are described. The author then presents some typical TDDB distributions showing the effects of fluorine contaminants and reports also a study of the TDDB dependence on the tested areas to verify if clustering of defects are present at such high fluorine concentrations. The author explains how he statistically treated the experimental results. He considered bimodal distributions separated in an intrinsic and an extrinsic part, showing in detail the effects of fluorine on the intrinsic and extrinsic failure mode. The author also presents some data on charge trapping to explain the above results and finally draws some conclusions.