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

Ag addition in chalcopyrite materials is known to lead beneficial changes in aspects of structural and electronic properties. In this work, the effects of Ag alloying of Cu(In,Ga)Se₂-based solar cells has been investigated. Wide bandgap (Ag,Cu)(In_1-,Gax)Se₂ (x = 0.75~0.8) films have been deposited using a three-stage co-evaporation with various Ag/(Ag+Cu) ratios. With Ag alloying the (Ag,Cu)(In_1-x,Ga_x)Se₂ (x~0.8) films were found to have greater grainsize and film thickness. Device were also fabricated with the (Ag,Cu)(In_1-x,Ga_x)Se₂ (x~0.8) films and their J-V and quantum efficiency measurements were carried out. The highest-efficiency (Ag,Cu)(In1-_x,_x)Se₂ solar cell with Eg > 1.5 eV had an efficiency of 12.2% with device parameters VOC = 0.810 V, JSC = 21.7 mA/cm ² , and FF = 69.0%.