High-dielectric constant (high-k) gate materials, such as HfSiOx and HfAlOx, fabricated by atomic-layer-deposition techniques were characterized using monoenergetic positron beams. Measurements of the Doppler broadening spectra of annihilation radiation and the lifetime spectra of positrons indicated that positrons annihilated from the trapped state by open volumes that exist intrinsically in amorphous structures of the films. The size distributions of the open volumes and the local atomic configurations around such volumes can be discussed using positron annihilation parameters, and they were found to correlate with the electrical properties of the films. We confirmed that the positron annihilation is useful technique to characterize the matrix structure of amorphous high-k materials, and can be used to determine process parameters for the fabrication of high-k gate dielectrics.
|Number of pages||6|
|Journal||Physica Status Solidi (C) Current Topics in Solid State Physics|
|Publication status||Published - 2007|
|Event||14th International Conference on Positron Annihilation, ICPA 14 - Hamilton, ON, Canada|
Duration: 2006 Jul 23 → 2006 Jul 28
ASJC Scopus subject areas
- Condensed Matter Physics