Search

In this work, RF magnetron co‐sputtering was used to fabricate molybdenum oxytelluride thin films with different atomic ratios. Scanning electron micrographs and atomic force micrographs revealed that pure Mo thin films were segregated. Thin films with 40% Te content portrayed needle‐like structures and thus had the largest Rq value of 2.48 nm. Contact angle measurements further supported the findings as the thin films with 40% Te content were the most hydrophobic. X‐ray photoelectron spectroscopy results revealed that the major oxidation states of Mo from Te‐poor to Te‐rich TFs were changed from high (+6) to low (+4 and/or +2). X‐ray diffraction data showed that peaks pertaining to molybdenum oxide species appeared, notably at 33.048° and 33.115°. Ultraviolet photoelectron spectroscopy and Kelvin probe measurements evinced that the work function increases with increasing Te content. Four‐point probe measurements revealed that molybdenum oxytelluride thin films tend to have higher electrical conductivity than pure Mo and Te thin films. [ABSTRACT FROM AUTHOR]

Bismuth telluride has garnered considerable attention owing to its versatile properties applicable in thermoelectric and antibacterial domains, as well as its intriguing topological insulating properties. In this work, our group fabricated bismuth telluride thin films with various ratios using radio frequency magnetron sputtering. The surface properties of these thin films were thoroughly analyzed by employing a diverse array of analytical techniques, including X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), four-point probe and contact angle (CA) measurements. Specifically, our XPS findings indicated that Bi is more susceptible to oxidation than Te following Ar+-ion etching. Pure Te thin films exhibited the highest Rq value of 31.2 nm based on AFM and SEM results due to their larger grain sizes. The XRD patterns revealed a peak at 27.75° for thin films with 20% Te, attributed to its rhombohedral structure. Moreover, thin films with 30% Te yielded the highest weighted average work function with a value of 4.95 eV after etching. Additionally, pristine Bi and Te thin films demonstrated the most robust hydrophobic properties compared to intermediate-composition thin films, as determined by CA measurements. [ABSTRACT FROM AUTHOR]