Crystallization of Ge2Sb2Te5 thin films by nano- and femtosecond single laser pulse irradiation.

ABSTRACT: The amorphous to crystalline phase transformation of Ge2Sb2Te5 (GST) films by UV nanosecond (ns) and femtosecond (fs) single laser pulse irradiation at the same wavelength is compared. Detailed structural information about the phase transformation is collected by x-ray diffraction and high resolution transmission electron microscopy (TEM). The threshold fluences to induce crystallization are determined for both pulse lengths. A large difference between ns and fs pulse irradiation was found regarding the grain size distribution and morphology of the crystallized films. For fs single pulse irradiated GST thin films, columnar grains with a diameter of 20 to 60 nm were obtained as evidenced by cross-sectional TEM analysis. The local atomic arrangement was investigated by high-resolution Cs-cor

SUBMITTER: Sun X 

PROVIDER: S-EPMC4904278 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature