Photoemission in microelectronic research: When technological developments allow to tackle new questions in the lab

Photoemission has always played an important role in the development of new microelectronic devices and processes and has quickly focused on the use of monochromatized Al Kd radiation in most commercial instruments. While, for instance, ARXPS using sample tilting or the use of high-energy photoemission at synchrotron facilities were available, their use remained confidential due to technical constraints such as measurement time, repeatability of the measurements and/or access to the facilities. In this paper, we show through some examples that the implementation of these features in a user-friendly setup in the laboratory considerably enhances the information retrieved from photoemission experiments.

Application of angle-resolved X-ray photon electron spectroscopy for interface and layer growth studies demonstrated on Ti/Ta-based films deposited on SiO2

X-ray photoelectron spectroscopy (XPS) is one of the main methods for elemental and bonding-state characterization in the near-surface region. Applying it as angle-resolved XPS (ARXPS), it is promising for non-destructive depth profiling in the nanometre-thickness range. The challenges for the application of ARXPS are discussed for the early film growth of Ti and Ta on SiO(2) produced by in situ magnetron sputtering. The measurements showed several phase-formation processes at the interfaces, which were used as the basis for the ARXPS data analysis and resulted in different interlayer growth information for Ti and Ta. From a systematic ARXPS data interpretation in combination with simulations, limits of the method are critically discussed.