此論文亦展示PiFM在奈米尺度下表徵SiC樣品表面特性的實用性，特別是通過評估表面聲子極化子（SPhP）模態在不同材料條件下（如再結晶、摻雜和應變），不同的行為。在不同的樣品中，我們檢測到SiC的SPhP有類似於其LO聲子的行為，且具有更高靈敏度。此外，PiFM在SiC薄膜層-基板邊界、SiC微電子晶體和SiC表面凹陷中取得了高分辨率圖像，凸顯此探測技術有希望在監測碳化矽或其他半導體材料奈米結構或微電子元件中獲得廣泛的應用。 ;This thesis explores the field of nano-spectroscopy using infrared photo-induced force microscopy (PiFM) in the presence of polaritonic surface modes. Silicon carbide (SiC), known for its significant infrared response in scattering-type scanning near-field optical microscopy (s-SNOM), is the primary material analyzed here. After comparing infrared local probe nano-spectroscopy techniques and providing a brief introduction to SiC, we obtain near-field spectra on layers of varying qualities. The analysis of these spectra suggests the use of a model combining an effective polarizability related to the probe-sample interaction and the term of loss in the material′s dielectric function. However, the addition of additional damping to better model the data appears necessary. The study demonstrates the presence of attractive photo-induced forces and suggests a significant role of contamination layers in the proper transmission of the signal.
We highlight the technique′s ability to characterize the surface properties of SiC, particularly through the sensitivity of the technique to surface phonon-polaritons (SPhP), revealing significant variations depending on crystallinity, doping, or mechanical constraints. The variations in the polariton peak are quite analogous to those obtained by Raman spectroscopy, but with significantly greater sensitivity and resolution. The employed method notably provides spatially highly resolved images of nano-indented samples and SiC-based microelectronic components, showing that it is an useful and promising local probe technique in monitoring the SiC-based nano-structures or microelectronic devices.
