The present invention provides a method and precursor structure to form a solar cell absorber layer. The method includes electrodepositing a first layer including a film stack including at least a first film comprising copper, a second film comprising indium and a third film comprising gallium, wherein the first layer includes a first amount of copper, electrodepositing a second layer onto the first layer, the second layer including at least one of a second copper-indium-gallium-ternary alloy film, a copper-indium binary alloy film, a copper-gallium binary alloy film and a copper-selenium binary alloy film, wherein the second layer includes a second amount of copper, which is higher than the first amount of copper, and electrodepositing a third layer onto the second layer, the third layer including selenium; and reacting the precursor stack to form an absorber layer on the base.