Thomas Iken

We investigated the thermal resistance of SnSe nanoflakes using scanning thermal microscopy (SThM), an extension of atomic force microscopy that allows for nanoscale thermal mapping. The nanoflakes studied ranged in thickness from 5 to 40 nm, enabling us to observe the thermal properties across a wide range of dimensions. Our findings reveal a clear trend of increasing thermal resistance with SnSe nanoflake thickness, suggesting that heat transport in SnSe is governed by diffusive mechanisms that limit the effectiveness of nanostructuring in further reducing thermal conductivity. This investigation showcases the capabilities of SThM for nanoscale thermal analysis, providing critical insights into the intrinsic thermal transport properties of SnSe.

X-ray photoelectron spectroscopy (XPS) is generally used for chemical analysis of surfaces and interfaces. This method involves the analysis of changes in binding energies and peak shapes of elements under consideration. It is also possible to use XPS to study the effect of x-ray radiation on the electrical properties of thin films. We measured the Si 2p peak using x-ray powers of 300 and 150 W on ∼135 nm silicon dioxide (SiO2) thin films grown on both n- and p-type substrates while applying DC or AC external biases. Using the shifts in the binding energy of the Si 2p peak, we calculated the resistances and the capacitances of the SiO2 thin film. The way that the binding energies of the Si 2p peak and the capacitance of the thin film change as a function of the type of Si substrate and the power of the x-ray are explained using band bending.