Porous germanium formed by low energy high dose Ag+-ion implantation

Abstract

A technical approach is proposed for the synthesis of thin porous PGe layers with Ag nanoparticles based on low-energy high-dose implantation of single-crystal c-Ge metal ions. To demonstrate a successes of this technique, we performed an Ag+-ion implantation of a polished c-Ge substrates with an energy of 30 keV at a dose of 1.5⋅1017 ion/cm2 and a current density of 5 μA/cm2. Methods of scanning electron and atomic force microscopy, as well as EDX analysis and electron backscattered diffraction was shown that as a result of the implantation on the c-Ge surface a porous amorphous PGe layer is formed of a spongy structure consisting of a network of intersecting Ge nanowires with an average diameter of ∼10–20 nm. At the ends of the nanowires, the synthesis of Ag nanoparticles is observed. It was found that the formation of pores during Ag+-ion implantation is accompanied by efficient spattering of the Ge surface.