Semiconductor laser device and method of manufacturing same.

摘要

A high-power low-noise semiconductor laser device required for light sources for an erasable optical disc and a method of manufacturing the device are disclosed. Especially, a self-sustained pulsating semiconductor laser device is disclosed in which an MQW structure is used for an active layer (4, 44 or 44a), and thus a kink output power and a light output power by which the self-pulsation is enabled are increased to 10 mW or more and noise is reduced. Another semiconductor laser device of a self-pulsation type is disclosed in which impurities are doped in the active layer to reduce the self-pulsating frequency to obtain a low-noise characteristic even if higher optical feeback occurs.