Patent ID: 6861271

Claim:
A method for fabricating a device that emits light in blue or green wavelengths comprising: i) providing a substrate comprising a surface layer of a group III-nitride, maintaining the substrate at a temperature ranging from 700° C. to 850° C., and forming a layer of Al u Ga 1-u N, wherein u ranges from 0 to 0.30, over the substrate; ii) maintaining the substrate at about the temperature of step i), and forming a layer of In x Ga 1-x N, wherein x ranges from 0 to 0.10, over the Al u Ga 1-u N; iii) maintaining the substrate at about the temperature of step i), and flowing indium-precursor at a flow rate of less than 100 μmol/min between 2 and 5 seconds, and N-precursor over the layer of In x Ga 1-x N to form quantum dots of In w Ga 1-w N, wherein w>0.20; iv) maintaining the substrate at about the temperature of step i), and forming a well layer of In y Ga 1-y N, wherein y is greater than x, over the quantum dots; v) maintaining the substrate around/at the temperature of step i), and forming a first cap layer of In z Ga 1-z N, wherein z ranges from 0 to 0.10, over the well layer; vi) forming a second cap layer of GaN or AlGaN over the first cap layer; thereby obtaining a device that emits light in blue or green wavelengths.