US Patent 7259397 Self-scanning light-emitting element array chip

Provided is a self-scanning light-emitting element array chip structured on a substrate using Si. A lattice mismatching buffer layer (32) is formed on a Si substrate (30). On the lattice mismatching buffer layer (32), successively stacked are an n-type AlGaAs layer (14), a p-type AlGaAs layer (16), an n-type AlGaAs layer (18), and a p-type AlGaAs layer (20) in this order. On the AlGaAs layer (20) provided is an anode electrode (22), on the AlGaAs layer (18) a gate electrode (24), on the bottom surface of the GaAs substrate a cathode electrode (26).