Experimental and theoretical EBIC analysis for grain boundary and CdS/Cu (In, Ga)Se ₂ heterointerface in Cu (In, Ga)Se ₂ solar cells

The behavior of carriers for an electron-beam-induced current (EBIC) evaluation is experimentally and theoretically analyzed the polycrystalline Cu (In, Ga)Se2 (CIGS) thin-film solar cells. experimental EBIC signal in-depth profiles CIGS layers show four features: peaks at grain boundaries (GBs), narrowed near surface, shifted double GBs surface. Operating principles cell devices under electron–hole pair excitation are systematically revealed utilizing a two-dimensional theoretical simulation: (i) caused by high hole barrier, including valence band offset (ΔEV) bending GBs; (ii) narrowing surface defect densities GBs, grading conduction minimum, acceptor concentration (Na) along with depth direction; (iii) shift in donor-like surface; (iv) thick layer (SL) ΔEV barrier GBs. These findings analysis will help to comprehensively understand complex carrier transport mechanism realizing highest-efficiency