Current Photovoltaic Research ISSN:2288-3274(Print) 2508-125X(Online)

Two different window‐structured CuInGaSe2(CIGS) solar cells, i.e., CIGS/thin‐CdS/ZnO:B(sample A) and CIGS/very thin‐CdS/Zn(S/O)/ZnO:B(sample B), were prepared, and the diffusivity of Zn, Cd, S, and B atoms, respectively, in the CIGS, ZnO or Zn(S/O) layer was estimated by a theoretical fit to experimental secondary ion mass spectrometer data. Diffusivities of Zn, Cd, S, and B atoms in CIGS were 2.0 × 10^-13(1.5 × 10^-13), 4.6 × 10^-13(4.4 × 10^-13), 1.6 × 10^-13(1.8× 10^-13), and 1.2 × 10^-12 cm²/s at 423K, respectively, where the values in parentheses were obtained from sample B and the others from sample A. The diffusivity of the B atom in a Zn(S/O) of sample B was 2.1 × 10^‐14 cm²/sec. Moreover, the diffusivities of Cd and S atoms diffusing back into ZnO(sample A) or Zn(S/O)(sample A) layers were extremely low at 423K, and the estimated diffusion coefficients were 2.2 × 10^-15 cm²/s for Cd and 3.0 × 10^-15 cm²/s for S.