Compressive thermal stress and microstructure-driven charge carrier transport in silicon oxycarbide thin films

Hierarchical microstructure growth in a precursor‐derived SiOC thin film prepared on silicon substrate

“…As the annealing temperature of the thin film increases, it is shown that the size of the carbon domains in the segregated areas increases faster than that of the sp2‐hybridized carbon phase present in the amorphous matrix. This is in agreement with a previous study, in which was also shown that the sp2‐carbon in the segregations of the SiOC thin films is higher graphitized than the sp2‐carbon from the amorphous matrix 25 …”

“…This is in agreement with a previous study, in which was 1), ( 2), ( 3) and ( 4) also shown that the sp2-carbon in the segregations of the SiOC thin films is higher graphitized than the sp2-carbon from the amorphous matrix. 25 The SiOC thin films on Si substrate were prepared for TEM and EELS analyses by preparing the cross-section via the FIB technique. Lamellae were taken along the matrices of the film, while additional lamellae were prepared for samples where oxygen-depleted segregations were evident.…”

“…22,23 A significant amount of literature is available on the synthesis approach and characterization of SiOC, although the majority is dedicated to powder and monolithic samples. In our latest work on SiOC thin film deposited on a silicon substrate, the evolution of the SiC and free carbon phases were documented at a temperature of 1400 • C. 24,25 A micro-scale segregation of phases was observed on the surface of the film; the segregations were found to consist of sp 2-h ybridized carbon and nanocrystalline β-SiC dispersed within an amorphous silicon oxycarbide matrix. The Si-O-C system is known to follow two processes when exposed to temperatures well beyond 1000 • C: The first process involves the partitioning of the glassy SiO 4−x C x network and the formation of amorphous silica and SiC nanodomains, latter may crystallize; the second process represents the carbothermal reaction between the phaseseparated silica and the excess carbon, complemented by the growth of crystalline SiC and release of gaseous CO. 9 These processes were extensively studied and are relatively well understood for monolithic SiOC.…”

“…A significant amount of literature is available on the synthesis approach and characterization of SiOC, although the majority is dedicated to powder and monolithic samples. In our latest work on SiOC thin film deposited on a silicon substrate, the evolution of the SiC and free carbon phases were documented at a temperature of 1400°C 24,25 . A micro‐scale segregation of phases was observed on the surface of the film; the segregations were found to consist of sp 2 ‐hybridized carbon and nanocrystalline β‐SiC dispersed within an amorphous silicon oxycarbide matrix.…”

SiOC-Based Strain Gauge with Ultrahigh Piezoresistivity at High Temperatures

“…About monolithic samples, we proposed that the percolation path of the system decreases as a combined effect of the presence of two conductive phases, i.e., the free carbon and SiC, with the free carbon domains present in both the matrix and the segregation. 24 This resulted in an improved conductivity of the SiOC film at 25 °C, ca. 16.40 S cm −1 .…”