Amkreutz, D.; Preissler, N.; Thi-Trinh, C.; Trahms, M.; Sonntag, P.; Schlatmann, R.; Rech, B.: Influence of the precursor layer composition and deposition processes on the electronic quality of liquid phase crystallized silicon absorbers. Progress in Photovoltaics 26 (2018), p. 524-532
Open Access Version
Liquid phase crystallization using line-shaped energy sources such as CW-diode lasers or electron beams has proven to form mc-Si layers on borosilicate or boro-/aluminosilicate glass that exhibit wafer equivalent grain sizes and electronic quality. In this work we characterize the impact of the employed dielectric interlayer stack sandwiched between glass and absorber on the electronic quality. For this purpose we investigate a large variety of test cell results achieved in the past on different interlayer stacks comprised of silicon oxide, silicon nitride as well as silicon oxynitride deposited by means of plasma enhanced chemical vapour deposition (PECVD) or plasma oxidation and employ i(v), SunsVoc, quantum efficiency measurements and photolumiscence (PL) imaging to assess the electronic properties of the crystallized absorbers. The results are compared to state-of the art interdigitated back-contact (IBC) cells and literature values. Based on these findings we conclude that at the present state of interlayer development the bulk quality imposes the limits in cell efficiency and investigate potential approaches to increase the bulk quality of LPC-Si absorbers.