Loss analysis and efficiency potential of p-type MWT–PERC solar cells

A loss analysis is carried out for monocrystalline large-area p-type metal wrap through passivated emitter and rear cells (MWT–PERC) with thermal SiO2/SiNx surface passivation reaching a maximum conversion efficiency of 20.6%. Analytical and numerical device modelling identifies the most important loss mechanisms and allows for a separation of the different series resistance contributions and various short circuit current loss mechanisms. Based on the extracted data, an estimation of the possible maximum conversion efficiency for p-type MWT–PERC solar cells is given.

Graphical AbstractFigure optionsDownload as PowerPoint slideHighlights
► An in-depth characterisation of MWT–PERC devices with η=20.6% is presented.
► Identification of major loss mechanisms allows for specific technological optimisation.
► In spite of LID, a low base resistivity of ∼0.7 Ω cm is beneficial for p-type PERC devices.
► A conversion efficiency of >21% is expected for p-type Cz-Si MWT–PERC devices.