Characterization of sputter deposited tungsten films for x-ray multilayers

Abstract

The microstructural and optical properties of tungsten thin films prepared by dc magnetron sputtering were investigated as a function of the argon pressure. The films were characterized by x-ray photoelectron spectroscopy (XPS), scanning tunneling microscopy (STM), x-ray diffraction (XRD), grazing x-ray reflectometry (GXR), and spectroscopic ellipsometry (SE). From the analysis of the XPS data, the films were found to consist of a base tungsten layer, a graded oxide transition layer, and a surface oxide layer. Also, the thickness of the oxide layers were determined. XRD indicated that the films were either amorphous or composed of crystallites with grain size <100 Å. STM and GXR have revealed that the films grown at low pressures were the smoothest. Finally, SE measurements allowed the determination of the dielectric function of a compact tungsten layer. Further SE analysis of the films indicated that with increasing argon pressure, the films developed into a more voided columnar structure.

Morphology control of tungsten nanorods grown by glancing angle RF magnetron sputtering under variable argon pressure and flow rate

“…The wide range to technological applications of tungsten films, for example, semiconductor interconnect layers as diffusion barriers [25], X-ray mirrors [26], X-ray field as absorbing layer [27], field ionization [22], etc., has motivated us to do a study where both morphology and surface roughness of tungsten thin films can be tailored. Therefore, a systematic study was carried out to address the influence of Ar pressure and Ar flow rate on the morphology and surface roughness of WNRs.…”

Analysis of Tungsten-Alumina Nanocomposite Thin Films on SS304 Substrate

“…The Al2O3 coating acts as a bond layer [19] so that the deposited thin films do not peel off and the deposited thin films are characterized. The tungsten and alumina thin films deposited using a cosputtering were characterized using 410 -solar instrument for measuring solar absorptance and ET 100 Emissometer for measuring thermal emittance [20]. Table 3 shows the measured values of each of the samples coated on SS304 substrates with tungsten and alumina thin films.…”

Evaluation of the initial growth of electroless deposited Co(W,P) diffusion barrier thin film for Cu metallization

“…This excludes the possibility that W is present as an oxide inside the film. In addition, WO 3 and WO 2 at the surface of the top Co(W,P) layer could result from the oxidation of W [30]. The best known example is the oxidation of freshly prepared tungsten STM tip.…”