Pulsed laser deposition of single-crystalline Cu(7)In(3)/CuIn(0.8)Ga(0.2)Se(2) core/shell nanowires

Single-crystalline Cu(7)In(3)/CuIn(0.8)Ga(0.2)Se(2) (CI/CIGS) core/shell nanowires are fabricated by pulsed laser deposition with Ni nanoparticles as catalyst. The CI/CIGS core/shell nanowires are made up of single-crystalline CI cores surrounded by single-crystalline CIGS shells. The CI/CIGS nanowires are grown at a considerably low temperature (350°C ~ 450°C) by vapor-liquid-solid mode combined with vapor-solid mode. The distribution density of the nanowires increases with the increasing of the deposition duration, and the substrate temperature determines the lengths of the nanowires. The U-V absorption spectra of the CIGS thin films with and without the CI/CIGS core/shell nanowires demonstrate that the CI/CIGS nanowires can remarkably enhance the absorption of CIGS thin films in the spectrum range of 300 to 900 nm. PACS: 61.46. + w; 61.41.e; 81.15.Fg; 81.07.b