Analysis of Local Minority Carrier Diffusion Lengths in Liquid Phase Crystallized Silicon Thin Film Solar Cells

We develop a method to quantify the local minority carrier diffusion lengths in interdigitated back contact solar cells having a 10 m thick liquid phase crystallized LPC Si absorber by light beam induced current LBIC measurements. The method is verified by 2 D simulations of the LBIC signals using ASPIN3. The effective minority carrier diffusion lengths determined this way range between 33 and 44 m inside a grain, which proves that advanced cell concepts like an interdigitated back contact IBC system are well suited for the LPC absorbers. Furthermore, the method has the potential to help improve the optimization of contact system geometries, and it may be used to understand the influences of different grain orientations and improve the LPC Si absorber fabrication proces