Sharp began mass production of tandem thin-film solar cells with a tandem-junction structure (amorphous silicon and microcrystalline silicon) in September 2005. Now, Sharp is making thin-film solar cells with a triple-junction structure, which consists of two amorphous layers and a microcrystalline layer. With these triple-junction thin-film solar cells, Sharp has achieved module conversion efficiencies of approximately 10%, at the industry's top level.