| abstract |
An aluminium gallium indium phosphide (AlGaInP)-based semiconductor laser device is provided. On a main surface of a semiconductor substrate formed of n-type GaAs (gallium arsenide), from the bottom layer, an n-type buffer layer, an n-type cladding layer formed of an AlGaInP-based semiconductor containing silicon (Si) as a dopant, an active layer, a p-type cladding layer formed of an AlGaInP-based semiconductor containing magnesium (Mg) or zinc (Zn) as a dopant, an etching stopper layer, and a p-type contact layer are formed. Here, when an Al composition ratio x of the AlGaInP-based semiconductor is taken as a composition ratio of Al and Ga defined as (Al x Ga 1−x ) 0.5 In 0.5 P, a composition of the n-type cladding layer is expressed as (Al xn Ga 1−xn ) 0.5 In 0.5 P (0.9<xn<1) and a composition of the p-type cladding layer is expressed as (Al xp Ga 1−xp ) 0.5 In 0.5 P (0.9<xp≦1), and xn and xp satisfy a relationship of xn<xp. |