Patent ID: RE40163

Claim:
A semiconductor light-emitting element comprising: a sapphire single crystal substrate having a surface nitriding layer on a main surface thereof , an underlayer, formed on the surface nitriding layer on the main surface of the substrate, and being made of a first semi-conducting nitride material including Al element and having a full width at half maximum (FWHM) in X-ray rocking curve of 90 seconds or below, a first conductive layer, formed on the underlayer, made of a second semi-conducting nitride material including at least one element selected from the group consisting of Al, Ga and In, a first cladding layer, formed on the first conductive layer, made of a third semi-conducting nitride material including at least one element selected from the group consisting of Al, Ga and In, a light-emitting layer composed of a base layer, formed on the first cladding layer, made of a fourth semi-conducting nitride material including at least one element selected from the group consisting of Al, Ga and In and plural isolated island-shaped single crystal portions, embedded in the base layer, made of a fifth semi-conducting nitride material including at least one element selected from the group consisting of Al, Ga and In and having an in-plane lattice constant larger than that of the third semi-conducting nitride material, a second cladding layer, formed on the light-emitting layer, made of a sixth semi-conducting nitride material including at least one element selected from the group consisting of Al, Ga and In, and a second conductive layer, formed on the second cladding layer, made of a seventh semi-conducting nitride material including at least one element selected from the group consisting of Al, Ga and In, the bandgap of the third semi-conducting nitride material constituting the first cladding layer, the bandgap of the fourth semi-conducting nitride material constituting the base layer and the bandgap of the fifth semi-conducting nitride material becoming larger by turns to satisfy the following relationship: the band gap of the fourth semi- conducting nitride material>the bandgap of the fifth semi - conducting nitride material .