Pierre-Olivier Chapuis, CNRS - INSA Lyon
Scanning Thermal Microscopy—Probing Temperature and Heat Dissipation Down to the Few-Nanometers Scale
Written by Bharati Neelamraju
Pierre-Olivier Chapuis covered the use of scanning thermal microscopy, which is based on the concept of atomic force microscopy but with heat. This technique has applications at micro- and nanoscale levels of samples where the researchers can characterize local thermal conductivity, local melting temperature, and local heating in ICS, for example. Some other uses of this technique include nano-lithography and data storage. This technique competes with other optical methods and has a shortcoming when the sample roughness is too high. Chapuis showed that in their laboratory, SThM is used under varying environments that include vacuum, a homemade SEM system, and a homemade cryo cooled sample. Chapuis discussed the sensitivities of a microprobe and a nanoprobe with varying materials and emphasized the need for proper calibration. He showed that as of now, thinner samples had a higher error bar while thicker samples had very precise measurements. He emphasized that SThM makes measurements in the cross plane direction while most other techniques only do it in the in-plane direction of the sample. The final dream of this project is to be able to take precise thermal conductivity measurements with no contact under vacuum. From theoretical calculations the researchers compute a flux between probe and sample that gives a spatial resolution for non-contact SThM to be approximately 10 nm.