Double-sided TOPCon solar cells on textured wafer with ALD SiOx layer

Double-sided, front and rear, tunnel oxide passivated contact (TOPCon) of crystalline silicon (c-Si) solar cells on textured wafer is presented. The double-sided TOPCon structure is composed of (p) poly-Si/SiOx/(n) c-Si/SiOx/(n) poly-Si, where the silicon oxide (SiOx) layer is formed by atomic layer deposition (ALD). With a 0.6 ± 0.1 nm-thick SiOx layer, an 18.8 %-efficiency solar cell is fabricated, where an excellent short circuit current above 39 mA/cm2 is confirmed for a front grid structure. The solar cell performance is improved by optimizing the boron and hydrogen diffusion profiles near the p-side SiOx/c-Si interface.