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Title: The dependency of different stress-level SiN capping films and the optimization of D-SMT process for the device performance booster in Ge n-FinFETs

Abstract

The capping stressed SiN film is one of the most important process steps for the dislocation stress memorization technique (D-SMT), which has been used widely in the current industry, for the electron mobility booster in the n-type transistor beyond the 32/28 nm technology node. In this work, we found that the different stress-level SiN capping films influence the crystal re-growth velocities along different directions including [100] and [110] directions in Ge a lot. It can be further used to optimize the dislocation angle in the transistor during the D-SMT process and then results in the largest channel stress distribution to boost the device performance in the Ge n-FinFETs. Based on the theoretical calculation and experimental demonstration, it shows that the Ge three dimensional (3D) n-FinFETs device performance is improved ∼55% with the usage of +3 GPa tensile stressed SiN capping film. The channel stress and dislocation angle is ∼2.5 GPa and 30°, measured by the atomic force microscope-Raman technique and transmission electron microscopy, respectively.

Authors:
;  [1]
  1. Department of Mechanical Engineering, National Taiwan University, Taipei 10617, Taiwan (China)
Publication Date:
OSTI Identifier:
22489116
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 107; Journal Issue: 7; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DISLOCATIONS; ELECTRON MOBILITY; FILMS; MICROSCOPES; OPTIMIZATION; PERFORMANCE; PRESSURE RANGE GIGA PA; SILICON NITRIDES; STRESSES; TRANSISTORS; TRANSMISSION ELECTRON MICROSCOPY

Citation Formats

Liao, M.-H., E-mail: mhliaoa@ntu.edu.tw, and Chen, P.-G. The dependency of different stress-level SiN capping films and the optimization of D-SMT process for the device performance booster in Ge n-FinFETs. United States: N. p., 2015. Web. doi:10.1063/1.4929146.
Liao, M.-H., E-mail: mhliaoa@ntu.edu.tw, & Chen, P.-G. The dependency of different stress-level SiN capping films and the optimization of D-SMT process for the device performance booster in Ge n-FinFETs. United States. doi:10.1063/1.4929146.
Liao, M.-H., E-mail: mhliaoa@ntu.edu.tw, and Chen, P.-G. 2015. "The dependency of different stress-level SiN capping films and the optimization of D-SMT process for the device performance booster in Ge n-FinFETs". United States. doi:10.1063/1.4929146.
@article{osti_22489116,
title = {The dependency of different stress-level SiN capping films and the optimization of D-SMT process for the device performance booster in Ge n-FinFETs},
author = {Liao, M.-H., E-mail: mhliaoa@ntu.edu.tw and Chen, P.-G.},
abstractNote = {The capping stressed SiN film is one of the most important process steps for the dislocation stress memorization technique (D-SMT), which has been used widely in the current industry, for the electron mobility booster in the n-type transistor beyond the 32/28 nm technology node. In this work, we found that the different stress-level SiN capping films influence the crystal re-growth velocities along different directions including [100] and [110] directions in Ge a lot. It can be further used to optimize the dislocation angle in the transistor during the D-SMT process and then results in the largest channel stress distribution to boost the device performance in the Ge n-FinFETs. Based on the theoretical calculation and experimental demonstration, it shows that the Ge three dimensional (3D) n-FinFETs device performance is improved ∼55% with the usage of +3 GPa tensile stressed SiN capping film. The channel stress and dislocation angle is ∼2.5 GPa and 30°, measured by the atomic force microscope-Raman technique and transmission electron microscopy, respectively.},
doi = {10.1063/1.4929146},
journal = {Applied Physics Letters},
number = 7,
volume = 107,
place = {United States},
year = 2015,
month = 8
}
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