Initial growth of W‐based films deposited on Si studied with ARXPS

Surface & Interface Analysis

Vogel

Eckert

2014

Self Cite

For surface acoustic wave devices, piezoelectric substrates have to be coated with barrier and metallization layers. The interface formation plays an important role for the functionality of the layer systems. We used angle‐resolved XPS for nondestructive interface characterization of such material systems. However, the analyses are challenging for complex systems as considered here, because model calculations always have to be performed for data interpretation. To eliminate measuring uncertainties, in a first step, Monte Carlo simulations of angle‐resolved XPS measurement were performed. By use of such reliable data, system inherent uncertainties can be revealed. It is shown that the application of appropriate boundary conditions is inevitable the more complex the structures are. The use of high (near‐surface) measuring angles is discussed as one possible advantageous way. Copyright © 2014 John Wiley & Sons, Ltd.

Section: Introductionmentioning

confidence: 83%

ARXPS measurement simulation for improved data interpretation at complex Ta/Li‐niobate interfaces

Surface & Interface Analysis

Vogel

Eckert

2014

Self Cite

“…The general growth models for Ti-based materials were compared with those from the previous investigations for Ta and TaN, [4 -7] and from recent studies on W-based materials (only on Si substrates) [21] obtained by sputter deposition. Table 1 summarizes the main parameters.…”

Section: Comparison Of Ti Ta and W Depositionmentioning

confidence: 99%

Growth studies of Ti‐based films deposited on Si and SiO₂ using angle‐resolved XPS

Surface & Interface Analysis

2010

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Ti and TiN films with thicknesses of less than one monolayer and up to several nanometers were deposited by magnetron sputtering onto Si and SiO 2 . The samples were transferred immediately after deposition into the analysis chamber without breaking the vacuum to avoid oxide formation and contamination. Analysis was done by means of X-ray photoelectron spectroscopy (XPS) for elemental and bonding state characterization as well as by angle-resolved XPS (ARXPS) for nondestructive depth profiling. The XPS measurements indicated different phase formation processes at the interfaces, which were used as the base for the ARXPS data analysis. Growth properties for similarly deposited Ti-, Ta-and W-based films are compared. Copyright

“…Here, a part of a series of systematic studies of the growth of Ta-, (95,96) W- (97) and Ti- (98) based diffusion barrier layers on Si and SiO 2 substrates is discussed. Identification of interface chemical phases such as silicides and/or oxides was possible from peak shifts.…”

Section: Interfacesmentioning

confidence: 99%

X‐Ray Photoelectron Spectroscopy in Analysis of SurfacesUpdate based on the original article by Steffen Oswald,Encyclopedia of Analytical Chemistry, © 2000, John Wiley & Sons, Ltd.

Encyclopedia of Analytical Chemistry

2013

X‐ray photoelectron spectroscopy (XPS) is an analytical technique that uses photoelectrons excited by X‐ray radiation (usually Mg Kα or Al Kα) for the characterization of surfaces to a depth of 2–5 nm. Elemental identification and information on chemical bonding are derived from the measured electron energy and energy shifts, respectively. The use of ultrahigh vacuum (UHV) during analysis requires special sample handling. Depth profiling is possible using ion sputtering. In contrast to the most popular surface analytical technique, Auger electron spectroscopy (AES), nonconducting material can be investigated, weak material damage occurs, and the chemical shifts are easier to interpret. However, the lateral resolution of the complementary AES technique (typically down to 20 nm) is much better than for XPS (50 µm for standard equipment, down to lower than 3 µm for dedicated instruments). The detection limit (of about 0.1 at%) is not as low as for mass spectroscopic techniques, but the quantification from XPS peak area measurements is more reliable, even disclaiming standard sample measurements. This article briefly discusses the principles of the technique, sample requirements, and the typical measuring strategy. Possible information sources (elements, chemical bonding, depth and lateral distributions) are described and their quantification principles are summarized. The main part deals with typical applications relating to several material classes (metals, semiconductors, insulators, and polymers) to give an impression of the capabilities of the method over a wide range of research and technological problems. A comparison with further complementary analytical techniques is given as a summary. Technological developments in electronics, nanotechnology, polymers, biotechnology, and medicine are all concerned with surface‐related phenomena, suggesting sustained interest in XPS in the foreseeable future.