SEMICONDUCTOR LASER DEVICE

PURPOSE:To eliminate the need for a power supply for driving having large current capacity by burying a pectinate electrode in a semiconductor laminate so as to be opposed to two electrodes and form a Schottky junction. CONSTITUTION:A pectinate electrode 21 is buried in a semiconductor substrate 1 constituting a semiconductor laminate 7 so as to be opposed to electrodes 8 and 9 and shape a Schottky junction 23 between the substrate 1 and the electrode 21. When a modulation signal is applied between the electrode 9 and the electrode 21 on a semiconductor laser device in such constitution, depletion layers controlled in an extent corresponding to the voltage value of the modulation signal from the junction 23 are obtained in regions among the adjacent projections of the pectinate section 22b of the electrode 21 in the substrate 1. The amplitude of currents for driving passing through an active layer 3 is modulated by controlling the depletion layers. Accordingly, currents for driving, amplitude thereof is modulated by the large degree of modulation and which has a large value, need not be obtained from a power supply for driving and laser beams, intensity thereof is modulated, can be acquired at high speed.