Publications by authors named "P Gergaud"

Article Synopsis
  • This work presents dark-field X-ray microscopy (DFXM) as a powerful 3D imaging technique for analyzing novel gallium nitride (GaN) structures on nano-pillars designed for optoelectronic devices.
  • The GaN layers are expected to bond cohesively into a well-oriented film due to the softening of the SiO layer during growth, with DFXM achieving extremely precise orientation (standard deviation of 0.04°) for GaN nanostructures.
  • The findings from both nanoscale DFXM and macro-scale X-ray diffraction confirm that the coalescing GaN layers cause intentional misorientation in the silicon nano-pillars, highlighting the technique's potential for developing high-quality GaN
View Article and Find Full Text PDF

Electrical aging in lead zirconate titanate (PbZrTiO) thin films has been intensively studied from a macroscopic perspective. However, structural origins and consequences of such degradation are less documented. In this study, we have used synchrotron radiation to evaluate the behavior of ferroelectric domains by X-ray diffraction (XRD).

View Article and Find Full Text PDF

Ni-based intermetallics are promising materials for forming efficient contacts in GeSn-based Si photonic devices. However, the role that Sn might have during the Ni/GeSn solid-state reaction (SSR) is not fully understood. A comprehensive analysis focused on Sn segregation during the Ni/GeSn SSR was carried out.

View Article and Find Full Text PDF

The properties of group III-Nitrides (III-N) such as a large direct bandgap, high melting point, and high breakdown voltage make them very attractive for optoelectronic applications. However, conventional epitaxy on SiC and sapphire substrates results in strained and defective films with consequently poor device performance. In this work, by studying the nucleation of GaN on graphene/SiC by MOVPE, we unambiguously demonstrate the possibility of remote van der Waals epitaxy.

View Article and Find Full Text PDF

In this paper, SiGe nano-heteroepitaxy on Si and SiGe nano-pillars was investigated in a 300 mm industrial reduced pressure-chemical vapour deposition tool. An integration scheme based on diblock copolymer patterning was used to fabricate nanometre-sized templates for the epitaxy of Si and SiGe nano-pillars. Results showed highly selective and uniform processes for the epitaxial growth of Si and SiGe nano-pillars.

View Article and Find Full Text PDF