Performance of p-i-n Hydrogenated Amorphous Silicon Thin Film Solar Cells Device

Abstract

We have fabricated the p-i-n hydrogenated amorphous silicon (a-Si:H) thin films by glow discharge technique using silane (H2 diluted) at corning 7059 glass substrate (5 * 5 mm2) coated with indium tin oxide (ITO) in a single chamber reactor at plasma excitation frequency 13.56 MHz. The deposition parameter was: temperature depositions at 200 ˚C, pressure at 75-100 mTorr, power 40-50 W, power density 2-2.5 W/m2, doping ratio of 0.25-1 % and deposition rate 4-6 Å/s. The thickness of the p-i-n a-Si:H layers was varied between 530 to 560 nm. The thickness of p-layer was varied between 10 to 40 nm, i-layer and n-layer constant at a thickness of 500 nm and 20 nm. As a back contact, we used aluminum by the sputtering technique and ITO layer will act as the front contact of the cell. The solar cells were I-V characterized under the dark state (without illumination) and AM 1.5 (illumination mW/cm2) by the solar simulator. The device produced in the dark state has shown the presence of a current with a magnitude in the order of 10 − 3 A. The maximum energy conversion efficiency in this study was 4.6 % and fill factor 0.40.