An evaporation tool for forming a dopant structure on a front surface of a continuous workpiece, wherein the front surface includes a precursor layer to form Group IBIIIAVIA absorbers for solar cells and the dopant structure is used to introduce dopants into the precursor layer. The tool includes at least a first vapor source station to deposit a Group VIA material, such as Se, and a second vapor station to deposit a dopant material, such as Na, onto the continuous workpiece. A moving assembly of the tool holds and moves the continuous workpiece within the tool by feeding the continuous workpiece from a first end and taking up from a second end of the tool. A support assembly of the tool contacts a back surface of the continuous workpiece to remove the heat from and apply tension to the continuous workpiece during the process.