Optoelectronic devices incorporating single crystalline aluminum nitride substrate

An optoelectronic device adapted to emit ultraviolet light, comprising:

• an aluminum nitride single crystalline substrate prepared by physical vapor transport, wherein the dislocation density of the substrate is less than about 103 cm−2 and the Full Width Half Maximum (FWHM) of the double axis rocking curve for the (002) and (102) crystallographic planes is less than about 50 arcsec;
• and
• an ultraviolet light-emitting diode structure overlying the aluminum nitride single crystalline substrate and adapted to emit light at a wavelength of about 150 to about 300 nm, the diode structure comprising a first electrode electrically connected to an n-type AlGaN layer and a second electrode electrically connected to a p-type GaN layer, with a multi-well active region extending between the n-type layer and the p-type layer;
• wherein the optoelectronic device is characterized by:
• (i) a reverse leakage current less than about 10−5 A/cm2 at −10V;
• and (ii) an L80 of at least about 5000 hours at an injection current density of 28 A/cm2.