TY - JOUR
T1 - Electrical and mechanical properties of tantalum nitride thin films deposited by reactive sputtering
AU - Kim, Deok Kee
AU - Lee, Heon
AU - Kim, Donghwan
AU - Kim, Young Keun
N1 - Funding Information:
This work was supported by the National Research Laboratory Program, and by the Next Generation Non-Volatile Memory Program of Korea Ministry of Science and Technology.
Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2005/10/1
Y1 - 2005/10/1
N2 - The electrical resistivity and mechanical hardness of reactively sputtered tantalum nitride (TaN) thin films on ceramic substrates have been investigated. Depending on the nitrogen/argon gas flow rate ratio (defined as R), the resistivity of the tantalum nitride films varied unusually widely (10 7 orders) from metal to insulator. The big increase in the resistivity of the tantalum nitride films as the R value increased may be due to the theoretically predicted Ta vacancies and anti-site defects (excess N atoms occupying Ta sites) or thermodynamically stable N-rich phase formation under N-rich conditions. N-rich TaN film in this study (R=2) had a dramatically increased resistivity and seems to be a good candidate material as a seed layer and a capping layer of GMR sensor in data storage, while low-resistive stoichiometric TaN (R=0.5) is a good candidate material as a barrier layer in semiconductors with its low contact resistance. The hardnesses of underlayer (10 μm Al2O3), 100 nm Al2O3, and two TaN films (R=1 and 2) were similar and between 600 and 1600 kg/mm2. The hardness of the TaN film did not change much as the N content increased in this study, which seems to indicate that N-rich thermodynamically stable phases such as tetragonal Ta4N5 or orthorhombic Ta 3N5 (rather than TaN film with anti-site defects) have been formed as the N content increased.
AB - The electrical resistivity and mechanical hardness of reactively sputtered tantalum nitride (TaN) thin films on ceramic substrates have been investigated. Depending on the nitrogen/argon gas flow rate ratio (defined as R), the resistivity of the tantalum nitride films varied unusually widely (10 7 orders) from metal to insulator. The big increase in the resistivity of the tantalum nitride films as the R value increased may be due to the theoretically predicted Ta vacancies and anti-site defects (excess N atoms occupying Ta sites) or thermodynamically stable N-rich phase formation under N-rich conditions. N-rich TaN film in this study (R=2) had a dramatically increased resistivity and seems to be a good candidate material as a seed layer and a capping layer of GMR sensor in data storage, while low-resistive stoichiometric TaN (R=0.5) is a good candidate material as a barrier layer in semiconductors with its low contact resistance. The hardnesses of underlayer (10 μm Al2O3), 100 nm Al2O3, and two TaN films (R=1 and 2) were similar and between 600 and 1600 kg/mm2. The hardness of the TaN film did not change much as the N content increased in this study, which seems to indicate that N-rich thermodynamically stable phases such as tetragonal Ta4N5 or orthorhombic Ta 3N5 (rather than TaN film with anti-site defects) have been formed as the N content increased.
KW - A1. Hardness
KW - A1. Reactive sputtering
KW - A1. Resistivity
KW - A1. Roughness
KW - B1. TaN
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U2 - 10.1016/j.jcrysgro.2005.06.017
DO - 10.1016/j.jcrysgro.2005.06.017
M3 - Article
AN - SCOPUS:24644473555
SN - 0022-0248
VL - 283
SP - 404
EP - 408
JO - Journal of Crystal Growth
JF - Journal of Crystal Growth
IS - 3-4
ER -