Schematic drawing of the 4T perovskite/Si tandem module and the process routes of the architecture of the perovskite section [29,30]. (A: Architecture of the 4T2 perovskite/Si tandem module, with bottom and top sub-modules as well as module elements including encapsulant, frame, and items like ribbons, junction box (J-Box) and wiring. B: ITO (indium tin oxide) is the front and back TCO (transparent conductive oxide) électrodes; SnO₂ (tin oxide) is the ETL (electron transport layer); PVKA, Cs0.17FA0.83Pb(I0,83Br0.17)3, is the perovskite absorbers used in 1-step perovskite deposition; PVKB, Cs0.05MA0.4FA0.55Pb(I0.96Br0.04)3, is used in 2-step perovskite deposition; HTL (hole transport layer) is made of CuSCN (Copper(I) thiocyanate); Al₂O₃ (aluminum oxide) serves as barrier layer; P1, P2 and P3 represent the laser scribing patterns. C: Step-by-step architecture of the perovskite section).