Paper SA+AS+MG+SS-TuA3
Practical use of Photoemission with Synchrotron Radiation in Nanotechnology: From Soft to Hard X-rays

Tuesday, October 29, 2013, 2:40 pm, Room 203 C

Over the past 15 years, due to intrinsic limitations of laboratory X-ray sources, photoemission using synchrotron radiation has played an increasing role in solving issues of technologically-relevant materials and systems. With narrow spectral widths, synchrotron sources enable photoemission at uncomparable effective energy resolutions for refined assessment of chemical states at interfaces [1]. The broad energy range offers ultimate surface sensitivities with soft x-rays [2], and also much deeper photoelectron escape depths in the hard x-ray range which is crucial to investigate buried interfaces intrinsically found in devices. This contribution will highlight the advantages and achievements of hard x-ray photoemission (HAXPES) compared to soft x-ray photoemission, through a selection of recent studies performed on nanotechnological materials and devices (CMOS high-k/metal gate stacks, memory devices) [3]. Finally, we will briefly mention new developments: first, the extension of photoelectron spectromicroscopy (XPEEM) from chemical state and band structure imaging, to hard x-rays excitation (HAXPEEM) [4]. Second, the application of inelastic background analysis of HAXPES spectra.

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[2] K. Huang, P. Reiss, O. Renault et al., ACS Nano 4 (2010), 4799; O. Renault et al., Appl. Phys. Lett. 87 (2005), 163119.

[3] R. Boujama et al., J. Appl. Phys. 111 (2012), 054110; P. Calka et al., J. Appl. Phys. 109 (2011) 124507.

[4]C. Wiemann et al., Appl. Phys. Lett. 100 (2012), 223106.