Improving Efficiency of Evaporated Cu₂ZnSnS₄ Thin Film Solar Cells by a Thin Ag Intermediate Layer between Absorber and Back Contact

Figure 6

(a) Light - curve of the CZTS devices with and without the Ag intermediate layer measured at 25°C under AM 1.5 G illumination. The efficiency, , , FF, and shunt resistance are given in the inset table; (b) external quantum efficiency (EQE), internal quantum efficiency (IQE), and reflectance () of the CZTS solar cells with and without the Ag layer; and (c) band gap estimation plot (  × EQE)² versus , where is the photon energy. Band gap results are also listed in the inset table in (a).

(a)

(b)

(c)