The modern version of a dye solar cell was originally co-invented in 1988 by the chemists Brian O'Regan and Michael Grätzel at the public research university in Berkeley, California.
On top is a transparent anode made of fluoride-doped tin dioxide deposited on the back of a glass plate. On the back of this conductive plate is a thin layer of titanium dioxide, which forms into a highly porous structure with an extremely high surface area. The plate is then immersed in a mixture of a photosensitive dye and a solvent. After soaking the film in the dye solution, a thin layer of the dye is left covalently bonded to the surface of the titanium dioxide. A separate plate is then made with a thin layer of the iodide electrolyte spread over a conductive sheet, typically platinum metal. The two plates are then joined and sealed together to prevent the electrolyte from leaking. The anode is located on the titanium dioxide side, the cathode on the platinum side.