A Chemical Vapor Deposited Silicon Rich Silicon Carbide P-N Junction Based Thin-Film Photovoltaic Solar Cell

作者：Lee Chiao Ti^*; Tsai Ling Hsuan; Lin Yung Hsiang; Lin Gong Ru

来源：ECS Journal of Solid State Science and Technology, 2012, 1(6): Q144-Q148.

DOI：10.1149/2.005301jss

In contrast to silicon-based p-n junction photovoltaic solar cells (PVSCs), a silicon rich silicon carbide (SixC1-x)-based thin-film PVSC with enhanced absorption at the visible wavelength region. The silicon rich SixC1-x films are synthesized by using a low-substrate temperature and low-power plasma-enhanced chemical vapor (PECVD) system in a silane-rich environment. The molar ratio of the silicon atoms in SixC1-x grown at 500 degrees C was tunable from 0.63 to 0.66 when reducing RF plasma power from 100 to 20 W. The low-plasma PECVD growth gave the SixC1-x an enhanced broadband absorption at 400-600 nm, where the highest optical absorption coefficient was 1.3x10(5) cm(-1). The silicon rich composition also reduced the optical bandgap energy from 2.05 to 1.49 eV. This type of red-shifted cutoff wavelength promoted solar energy conversion at the near-infrared region. Consequently, an ITO/p-SixC1-x/n-SixC1-x/A1 PVSC with a silicon molar ratio of 66% enhanced its conversion efficiency from 5 x 10(-3) to 4.7% when the n-type SixC1-x thickness was reduced from 150 to 25 nm, which is attributed to the reduced series resistance to 0.6 Omega and the increased shunt resistance to 1500 Omega.

• 出版日期2012