A Universal Extraction Method for Physical Parameters Applied for J-V Curves of Solar Cells

In this article, we discuss a straightforward method of parameter extraction, which was used in two back-to-back connected Schottky diodes previously. We verified the universality and feasibility of this method by extracting the solar cell parameters from J to V curves. This method provides a flexible approach to extract parameters of some complex models that are impracticable using other methods. In addition, we discussed the authenticity problem for parameter extraction and its widely used solution, deforming the formula by using some approximation to make the object parameter the slope or intercept. We argued that it is necessary to analyze how the error transformed into the deductive curve, which is generally overlooked. Moreover, we illustrated the defect of the ordinary least squares method under the absolute least squares criterion. Under some conditions, such as when the point under larger coordinates has a larger error, it is more accurate to use the least squares method under the relative least-squares criterion.