JPS6421987A - Semiconductor light emitting device - Google Patents

Abstract

PURPOSE:To provide a new semiconductor laser whose oscillation wavelength is regulatable in a wider range than conventional lasers, by applying an electric field to a multiple quantum well structure selectively returning light generated in an active region by periodic diffraction, along the laminating direction of the structure, for the purpose of selecting a wavelength of return light and controlling the oscillation wavelength. CONSTITUTION:A semiconductor laser has an active region 3 and a multiple quantum well structure 4 superposed thereon for selectively returning light generated in the active region 3 by periodic diffraction. Carriers are injected into the active region through a hetero junction other than the multiple quantum structure 4, and an electric field is applied to the quantum well structure 4 along the laminating direction thereof, in order to select a wavelength of return light and to control an oscillation wavelength. For example, an N type InP buffer layer 2 and a P-type InGaAsP active layer 3 are deposited on an N-type InP semiconductor substrate 1. Further, about 10 to 50 layers in total of InGaAsP well layers 4a and N-type InP barrier layers 4b are deposited and laminated to provide a multiple quantum well structure 4 thereon. After that, a semi-insulating InP layer 5, a P-type InGaAsP layer 7, a high-resistance isolating region 8 and so on are provided.