TY - JOUR
T1 - Vacuum null-point scanning thermal microscopy
T2 - Simultaneous quantitative nanoscale mapping of undisturbed temperature and thermal resistance
AU - Cha, Juhang
AU - Shin, Hwijong
AU - Kwon, Ohmyoung
N1 - Funding Information:
This research was supported by the Basic Science Research Program ( NRF-2018R1A2B2002837 ) through the National Research Foundation of Korea (NRF), funded by the Ministry of Education, Science and Technology and a Korea University Grant.
Publisher Copyright:
© 2021 Elsevier Masson SAS
PY - 2022/2
Y1 - 2022/2
N2 - Null-point scanning thermal microscopy (NP SThM) quantitatively measures undisturbed temperature without the influence of changes in physical properties and surface topography of the specimen. Simultaneously NP SThM measures the ratio of the sum of the tip-specimen contact thermal resistance and the spreading thermal resistance of the specimen to the effective thermal resistance of the SThM probe. Hence, arguably, NP SThM is an ideal SThM that meets all the requirements of SThM. However, in practice, the use of NP SThM has been limited to one-dimensional profiling only, and two-dimensional extension of NP SThM has been virtually impossible so far. This is because NP SThM is very difficult to implement and ensure a sufficient measurement sensitivity. In this study, we enable two-dimensional extension of NP SThM with almost a 20-fold improvement in measurement sensitivity even under mild vacuum conditions (<10−3 Torr). Through rigorous analysis of the two-dimensional imaging results of vacuum NP SThM (VNP SThM), we demonstrate the ideal characteristics and performance of VNP SThM. With the ideal measurement characteristics, and the greater sensitivity and convenience, VNP SThM is proven to be an essential tool in the analysis of nanoscale energy transport and conversion occurring inside nanodevices and nanomaterials.
AB - Null-point scanning thermal microscopy (NP SThM) quantitatively measures undisturbed temperature without the influence of changes in physical properties and surface topography of the specimen. Simultaneously NP SThM measures the ratio of the sum of the tip-specimen contact thermal resistance and the spreading thermal resistance of the specimen to the effective thermal resistance of the SThM probe. Hence, arguably, NP SThM is an ideal SThM that meets all the requirements of SThM. However, in practice, the use of NP SThM has been limited to one-dimensional profiling only, and two-dimensional extension of NP SThM has been virtually impossible so far. This is because NP SThM is very difficult to implement and ensure a sufficient measurement sensitivity. In this study, we enable two-dimensional extension of NP SThM with almost a 20-fold improvement in measurement sensitivity even under mild vacuum conditions (<10−3 Torr). Through rigorous analysis of the two-dimensional imaging results of vacuum NP SThM (VNP SThM), we demonstrate the ideal characteristics and performance of VNP SThM. With the ideal measurement characteristics, and the greater sensitivity and convenience, VNP SThM is proven to be an essential tool in the analysis of nanoscale energy transport and conversion occurring inside nanodevices and nanomaterials.
KW - Atomic force microscope
KW - Null-point scanning thermal microscopy
KW - Quantitative measurement
KW - Scanning thermal microscopy
KW - Thermal resistance
KW - Undisturbed temperature
UR - http://www.scopus.com/inward/record.url?scp=85115008950&partnerID=8YFLogxK
U2 - 10.1016/j.ijthermalsci.2021.107268
DO - 10.1016/j.ijthermalsci.2021.107268
M3 - Article
AN - SCOPUS:85115008950
VL - 172
JO - International Journal of Thermal Sciences
JF - International Journal of Thermal Sciences
SN - 1290-0729
M1 - 107268
ER -