PURPOSE: To obtain a luminescent device having reduced leakage current, by forming a groove with a V-shaped cross-section in the surface of a semiconductor substrate, and growing a laminated structure consisting of an optical confinement layer having a relatively small forbidden band width and an active layer having a relatively large forbidden band width in the groove and a current constriction layer surrounding the groove in such a manner that the portion of the laminated structure within the groove and the other portion thereof are cut off from each other.

CONSTITUTION: A stripe-shaped projection is formed on the surface of an N type InP substrate 1. The area surrounding the projection is covered with a laminated structure consisting of an N type InP layer 2 and an InGaAsP layer 3, and a P type InP layer 4 is grown on the whole surface. A stripe-shaped mask 12 is provided on the layer 4, and etching is carried out to form a groove with a V-shaped cross-section in the center of the projection, the groove reaching the substrate 1. An N type InP optical confinement layer having a relatively small forbidden band width and an InGaAs active layer having a relatively large forbidden band width are laminated on the whole surface by liquid phase epitaxial growth. Thus, an optical confinement layer 5 and an active layer 6 are buried within the groove, and an optical confinement layer 5a and an active layer 6a which are cut off from the layers 5, 6 are formed on the current constriction layer 4 surrounding the groove. Thereafter, a P type InP confinement layer 7, a P type InGaAsP layer 8, and the like are laminated on the whole surface in a conventional manner.