Effects of RTA temperatures on conductivity and micro-structures of boron-doped silicon nanocrystals in Si-rich oxide thin films

Abstract

In this work, the B-doped Si rich oxide (SRO) thin films were deposited and then annealed using rapid thermal annealing (RTA) to form SiO2-matrix silicon nanocrystals (Si NCs). The effects of the RTA temperatures on the structural properties, conduction mechanisms and electrical properties of B-doped SRO thin films (BSF) were investigated systematically using Hall measurements, Fourier transform infrared spectroscopy and Raman spectroscopy. Results showed that the crystalline fraction of annealed BSF increased from 41.3% to 62.8%, the conductivity was increased from 4.48×10−3S/cm to 0.16s/cm, the carrier concentration was increased from 8.74×1017cm−3 to 4.9×1018cm−3 and the carrier mobility was increased from 0.032cm2V−1s−1 to 0.2cm2V−1s−1 when the RTA temperatures increased from 1050°C to 1150°C. In addition, the fluctuation induced tunneling (FIT) theory was applicable to the conduction mechanisms of SiO2-matrix boron-doped Si-NC thin films.