Characterization and PL Properties of Ge-Induced Crystallization of a-Si Films Deposited by Magnetron Sputtering

Abstract

In this paper, we present the characterization of Ge-induced crystallization of amorphous Si (a-Si) films deposited by magnetron sputtering. The film structures of a-Si films were characterized by Raman spectroscopy, Atomic Force microscope (AFM), and field emission scanning electron microscope (FESEM). The result show that 60% of a-si film with a layer of 400 nm Ge buried is crystallized at growth temperature of 800 °C. The surface roughness and average surface grain size obtained by AFM is 2.39 nm and 60 nm for the crystallized film, respectively. The films growth at temperature of 500°C and 650 °C shows a PL spectrum band from 1.6 eV to 1.8 eV, and the PL peak shifts to lower energy as the growth temperature increased. As for the film grown at 800 °C, the PL spectrum is nearly extinguished. The crystallization of a-Si film induced by buried Ge might be a useful technology to develop high quality poly-Si film without annealing.