Embodiments of the invention provide a method of forming a doped gallium arsenide based (GaAs) layer from a solution based precursor. The doped gallium arsenide based (GaAs) layer formed from the solution based precursor may assist solar cell devices to improve light absorption and conversion efficiency. In one embodiment, a method of forming a solar cell device includes forming a first layer with a first type of dopants doped therein over a surface of a substrate, forming a GaAs based layer on the first layer, and forming a second layer with a second type of dopants doped therein on the GaAs based layer.