Effects of fabrication method on defects induced by nitrogen diffusion to the hafnium oxide layer in metal–oxide–semiconductor field effect transistors
This study investigates how different metal gate fabrication methods induce variations in the defects which result from nitrogen diffusing into the hafnium oxide layer in metal–oxide–semiconductor field effect transistors (MOSFETs). By using the different fabrication methods of pre-TaN, post-TaN and...
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Published in | Thin solid films Vol. 620; pp. 43 - 47 |
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Main Authors | , , , , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
Elsevier B.V
01.12.2016
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Subjects | |
Online Access | Get full text |
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Summary: | This study investigates how different metal gate fabrication methods induce variations in the defects which result from nitrogen diffusing into the hafnium oxide layer in metal–oxide–semiconductor field effect transistors (MOSFETs). By using the different fabrication methods of pre-TaN, post-TaN and post-TiN annealing, the work-function difference between the gate material and the semiconductor can be adjusted, leading to apparent differences in threshold voltage (Vth). In addition, the results of slow and fast I–V NBTI measurements show that the amount of the bulk trapping in the post-TiN device is the highest, followed by the post-TaN device and then the pre-TaN device. In addition, a nitrogen interstitial defect phenomenon, resulting in a temporary shift of threshold voltage (Vth) which is highest in the post-TiN the lowest in the pre-TaN device, is determined by double sweep fast I–V measurements.
•The double sweep fast I-V measurement indicates that the recoverable trapped holes are process-related pre-existing defects and these defects are induced by nitrogen diffusion from the thermal annealing process.•The nitrogen generates the nitrogen interstitials when the nitrogen diffusion from TaN/TiN gate to HfO2 layer with post-TaN/TiN annealing process. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0040-6090 1879-2731 |
DOI: | 10.1016/j.tsf.2016.09.062 |