Abstract: An LED is provided with a p-type semiconductor region in the shape of an island being buried in an n-type semiconductor region from the surface of it, and forms a pn junction at the interface between these n-type region and p-type region. The pn junction has a bottom junction at the bottom of the n-type region and a side junction at the peripheral side face. The bottom junction comprises a first subjunction being deep and constant in junction depth and a second subjunction varying continuously in junction depth. The depth of the second subjunction is shallower than the depth of the first subjunction. The p-type region portion above the second subjunction is thinner in thickness than the p-type region portion above the first subjunction. A light passing through the p-type region portion of the former is less in absorptior and more in optical power of the output light. The total power of the output light of the whole LED is increased correspondingly to reduction in thickness of the p-type region.

Abstract: An LED is provided with a p-type semiconductor region in the shape of an island being buried in an n-type semiconductor region from the surface of it, and forms a pn junction at the interface between these n-type region and p-type region. The pn junction has a bottom junction at the bottom of the n-type region and a side junction at the peripheral side face. The bottom junction comprises a first subjunction being deep and constant in junction depth and a second subjunction varying continuously in junction depth. The depth of the second subjunction is shallower than the depth of the first subjunction. The p-type region portion above the second subjunction is thinner in thickness than the p-type region portion above the first subjunction. A light passing through the p-type region portion of the former is less in absorption and more in optical power of the output light. The total power of the output light of the whole LED is increased correspondingly to reduction in thickness of the p-type region.

Abstract: A substrate polishing apparatus is provided with: a turntable (36) having a polishing surface; a plate (11) having an attaching surface to which GaAs semiconductor wafers (12a through 12d) are attached; points (42a through 42d) for adjusting the gap between the GaAs semiconductor wafers (12a through 12d) attached to the plate (11) and the polishing surface of the turntable (36); and notches (16a through 16d) formed so that they extend from the portions of the plate (11), where the points (42a through 42d) are formed, to the circumference of the plate (11). A method for polishing a semiconductor substrate employs the substrate polishing apparatus.

Abstract: An end facet light emitting type LED has a slanted light emitting side wall relative to a substrate surface. A method for manufacturing end facet light emitting type light emitting devices prevents the pn-junction regions of the devices from being damaged while a semiconductor wafer is diced to separate light emitting devices from one another. A recess is formed on the semiconductor wafer having a depth which is deeper than the pn-junction. A portion to be cut during dicing of the wafer is vertically and horizontally separated from the pn-junction regions, so that if cracks occur when the wafer is diced, the cracks do not affect the light emitting characteristics of the devices.

Abstract: An end face light-emitting-type LED has a first-conductive-type semiconductor substrate and a second-conductive-type diffusion region formed on a first surface of the first-conductive-type semiconductor substrate so as to have a depth within a predetermined value. The first-conductive-type semiconductor substrate has a second surface which meets the first surface at a predetermined angle with the first surface. A junction between the first-conductive-type semiconductor substrate and the second-conductive-type diffusion region includes an inclined portion with regard to the first surface in the vicinity of an edge portion of the junction which is on a side of the second surface, and light emerges from the junction via the second surface.

Abstract: In a fabricating method for an end face light emitting type LED array, p-type regions are formed by diffusing impurities into portions of a semiconductor substrate, using a diffusion prevention film as a mask. Subsequently, using the diffusion prevention film as a mask again, the semiconductor substrate is etched to form a concave portion therein so that light-emission end faces are formed on a side of the concave portion. With this arrangement, a positional misalignment between the p-type regions and the light-emission end faces is prevented.