TY - JOUR
T1 - Thickness Effects on Crystal Growth and Metal–Insulator Transition in Rutile-Type RuO2 (100) Thin Films
AU - Kutsuzawa, Dai
AU - Oka, Daichi
AU - Fukumura, Tomoteru
N1 - Funding Information:
The authors thank T. Hasegawa of University of Tokyo for helpful discussions and Y. Matsumoto and S. Maruyama of Tohoku University for technical assistance. This work was supported by MEXT/JSPS (16K13958). D.K. was also supported by the JSPS through the Program for Leading Graduate Schools (MERIT).
Funding Information:
The authors thank T. Hasegawa of University of Tokyo for helpful discussions and Y. Matsumoto and S. Maruyama of Tohoku University for technical assistance. This work was supported by MEXT/JSPS (16K13958). D.K. was also supported by the JSPS through the Program for Leading Graduate Schools (MERIT).
Publisher Copyright:
© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2020/9/1
Y1 - 2020/9/1
N2 - The thickness dependence of crystal structure and electrical properties is studied for rutile-type RuO2 (100) thin films. The island growth mode results in a monotonically varying lattice strain along the a-axis from negative to positive with increasing thickness. Decrease in the thickness below 20 nm increases the resistivity drastically, resulting in insulating-like behaviors. The metallic behaviors of the thicker films are well explained by the modified Bloch–Grüneisen function as in bulk RuO2, where the strain has a significant influence on the conduction parameters. The insulating-like behaviors of the thinner films are assigned to 2D localization and Mott variable range hopping, reflecting the effects of the size and growth mode on electrical conduction.
AB - The thickness dependence of crystal structure and electrical properties is studied for rutile-type RuO2 (100) thin films. The island growth mode results in a monotonically varying lattice strain along the a-axis from negative to positive with increasing thickness. Decrease in the thickness below 20 nm increases the resistivity drastically, resulting in insulating-like behaviors. The metallic behaviors of the thicker films are well explained by the modified Bloch–Grüneisen function as in bulk RuO2, where the strain has a significant influence on the conduction parameters. The insulating-like behaviors of the thinner films are assigned to 2D localization and Mott variable range hopping, reflecting the effects of the size and growth mode on electrical conduction.
KW - epitaxial thin films
KW - metal–insulator transition
KW - pulsed laser deposition
KW - ruthenium dioxide
KW - strain engineering
UR - http://www.scopus.com/inward/record.url?scp=85087354017&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85087354017&partnerID=8YFLogxK
U2 - 10.1002/pssb.202000188
DO - 10.1002/pssb.202000188
M3 - Article
AN - SCOPUS:85087354017
SN - 0370-1972
VL - 257
JO - Physica Status Solidi (B): Basic Research
JF - Physica Status Solidi (B): Basic Research
IS - 9
M1 - 2000188
ER -