*3.2. Energy-Dispersive X-Ray Spectroscopy (EDX)*

EDX measurements were performed using a high-resolution scanning electron microscope (FE-SEM Sigma, Carl Zeiss Microscopy GmbH, Oberkochen, Germany). Spectra were analyzed using INCA Software (INCA Energy 250, INCA Oxford Instruments GmbH, Wiesbaden, Germany). EDX measurements were performed with samples deposited onto silicon substrates. As the EDX method is not particularly surface-sensitive, the detection volume is dependent on the acceleration voltage and includes the film as well as parts of the substrate. In order to eliminate the substrate response, the film atomic composition was estimated from a combined elaboration of two EDX spectra obtained from different acceleration voltages (10 kV and 16 kV) for each sample.
