Rapid formation of single crystalline Ge nanowires by anodic metal assisted etching

Abstract

Germanium nanowires are produced by a novel approach, combining two well known electrochemical and metal assisted chemical etching. The metal assisted etching procedure is enhanced by incorporation of HF in the catalytic solution and application of a constant bias to the substrate. Fast etching, caused by metal nanoparticles, facilitate pore nucleation for further pore growth. The improved current transport developed in the vicinity of the metal nanoparticles maintains a concentrated current density at the pore tip which results in an elongation of the pores in one direction and formation of long nanowires. With this new approach it is possible to fabricate nanowires with diameter below 100 nm and tens of micrometers long.