The Deep Level Defects with Boron Atoms Configuration in Amorphous Silicon Solar Cells by DLTS and XPS

In this paper, we investigate the changes in the activation energy for electron capture in boron doped hydrogenated amorphous silicon layers. The boron doping level was varied by controlling the volume fraction of B2H6 in SiH4. As the volume fraction of B2H6 in SiH4 increases, the four-fold coordinated boron atoms increase. The four-fold coordination forms positively charged dangling bonds, which can lead to a decrease in the activation energy of from 1.24 eV to 1.09 eV for the electron capture. The correlation between the coordination of boron atoms and deep level defects was demonstrated by X-ray Photoelectron spectroscopy (XPS) and deep level transient spectroscopy (DLTS).