The Influence of the Base Material Parameters on Quantum and Photoconversion Efficiency of the Si Solar Cells

Abstract

The influence of a p-type Si with different resistivity, charge carrier lifetime and emitter dopant impurities concentration on the crystalline silicon solar cells parameters were analyzed and experimentally checked. The findings were determined by quasi-steady-state photoconductance, current-voltage and spectral response methods. The study was accompanied by solar device simulation using a numerical PC1D program. The highest photoconversion efficiency of 15.13 % was obtained for the moncrystalline (Cz-Si) solar cell with a base resistivity of 1.8 Ωcm and an effective charge carrier lifetime of 22.9 µs. The results clearly confirmed the importance concerning the dopant level in a Si base material in relation to open circuit voltage and short circuit current possible to obtain from the solar cell. Reduction of a base material resistivtiy leads to a lower value of an effective charge carrier lifetime and photoconversion efficiency both for Cz-Si and multicrystalline (mc-Si) solar cells. The experimental results and calculation showed, that in the case of a solar cell produced on the basis of crystalline silicon, the most important spectral range for an efficiency of a cell is covering a wavelength range of 587 ÷ 838 nm.

The influence of emitter resistance on the electrical parameters of mono- and multicrystalline silicon solar cells

“…The wavelength range from 580 to 830 nm is the most important spectral interval for the work of crystalline silicon solar cells in real conditions (Panek, 2016). As can be seen in Figure 7, the largest changes of EQE relative to different R sheet can be observed at a wavelength of 460 nm.…”

“…The efficiency of the crystalline Si cells produced on an industrial scale reach between 14 and 20 per cent (Green et al, 2014). The quality and efficiency of solar cell mainly depends on the electrical properties of the base material (silicon) and also on the technological conditions (Panek, 2016). It is related to the type of material: whether it is p or n. This feature is a result of the doping process in which boron or phosphorus (N A ) added to the molten silicon to change it into an p-type or n-type Si (Tyagi et al, 2013).…”