Blue light emitting diode formed in silicon carbide

A light emitting diode formed in silicon carbide that emits light in the blue to violet portion of the visible spectrum and comprising:

• a p-type substrate of alpha-type silicon carbide;
• an ohmic contact to said substrate;
• a substantially uncompensated p-type monocrystalline epitaxial layer of alpha-type silicon carbide upon said p-type substrate;
• a substantially uncompensated n-type monocrystalline epitaxial layer of alpha-type silicon carbide upon said p-type epitaxial layer and forming a p-n junction with said p-type layer, said n-type epitaxial layer having a carrier concentration greater than the carrier concentration of said p-type epitaxial layer;
• and
• an ohmic contact to said n-type epitaxial layer, said diode producing a peak emission at a wavelength of between about 455 and 460 nanometers with a spectral half width at peak wavelength of no more than about 50 nanometers.

A light emitting diode formed in silicon carbide that emits light in the blue to violet portion of the visible spectrum and comprising:

• an n-type substrate of alpha-type silicon carbide;
• an ohmic contact to said n-type substrate;
• a substantially uncompensated n-type monocrystalline epitaxial layer of alpha-type silicon carbide upon said n-type substrate;
• a substantially uncompensated p-type monocrystalline epitaxial layer of alpha-type silicon carbide upon said n-type epitaxial layer and forming a p-n junction with said n-type epitaxial layer, said p-type epitaxial layer having a carrier concentration greater than the carrier concentration of said n-type epitaxial layer;
• and
• an ohmic contact to said uncompensated p-type epitaxial layer, said diode producing a peak emission of between about 424 and 428 nanometers with a spectral half width at peak wavelengths of no greater than about 50 nanometers.

A light emitting diode formed in silicon carbide that emits light in the blue to violet portion of the visible spectrum and comprising:

• a p-type substrate of alpha silicon carbide;
• an ohmic contact to said p-type substrate;
• a substantially uncompensated p-type monocrystalline epitaxial layer of silicon carbide upon said p-type substrate;
• a first substantially uncompensated n-type monocrystalline epitaxial layer of alpha silicon carbide upon said p-type epitaxial layer, and having a carrier concentration less than the carrier concentration of said p-type epitaxial layer;
• a second substantially uncompensated n-type monocrystalline epitaxial layer of silicon carbide upon said first n-type epitaxial layer, and having a carrier concentration greater than the carrier concentration of said first n-type epitaxial layer;
• and
• an ohmic contact to said second n-type epitaxial layer, wherein said second n-type epitaxial layer forms a conductive surface that moderates the current crowding that would otherwise occur about said contact to said second n-type epitaxial layer, said diode producing a peak emission of between about 424 and 428 nanometers with a spectral half width at peak wavelength of no greater than about 50 nanometers.

A light emitting diode formed in silicon carbide that emits light in the blue to violet portion of the visible spectrum and comprising:

• an n-type substrate of alpha-type silicon carbide;
• an ohmic contact to said n-type substrate;
• a substantially uncompensated n-type monocrystalline epitaxial layer of alpha-type silicon carbide upon said n-type substrate;
• a compensated p-type monocrystalline epitaxial layer of alpha-type silicon carbide upon said uncompensated n-type epitaxial layer and forming a p-n junction with said n-type epitaxial layer;
• and
• an ohmic contact to said compensated p-type epitaxial layer.

A light emitting diode formed in silicon carbide that emits light in the blue to violet portion of the visible spectrum and comprising:

• an n-type substrate of alpha silicon carbide;
• a compensated n-type monocrystalline epitaxial layer of alpha silicon carbide upon said substrate;
• and
• a substantially uncompensated p-type monocrystalline epitaxial layer upon said n-type epitaxial layer, said p-type epitaxial layer having a carrier concentration greater than the carrier concentration of said n-type epitaxial layer;
• and in which said diode produces a peak emission at a wavelength of between about 475 and 480 nanometers with a spectral half width at peak wavelength of no more than about 50 nanometers.

A light emitting emitting diode formed in silicon carbide that emits light in the blue to violet portion of the visible spectrum and comprising:

• a p-type substrate of alpha silicon carbide;
• a compensated p-type monocrystalline epitaxial layer of alpha silicon carbide upon said susbtrate;
• and
• a substantially uncompensated n-type monocrystalline epitaxial layer upon said compensated p-type epitaxial payer and forming a p-n junction with said compensated p-type layer, said n-type epitaxial layer having a carrier concentration greater than the carrier concentration of said compensated p-type epitaxial layer.

A light emitting diode formed in silicon carbide that emits light in the blue to violet portion of the visible spectrum and comprising:

• a p-type substrate formed of alpha silicon carbide;
• an ohmic contact to said substrate;
• a substantially uncompensated p-type monocrystalline epitaxial layer formed of alpha silicon carbide upon said substrate;
• a compensated n-type monocrystalline epitaxial layer upon said p-type epitaxial layer, said n-type epitaxial layer having a carrier concentration less than the carrier concentration of said p-type epitaxial layer;
• and
• a substantially uncompensated n-type monocrystalline epitaxial layer upon said compensated n-type epitaxial layer and having a carrier concentration greater than the carrier concentration of said compensated n-type epitaxial layer;
• and
• an ohmic contact to said uncompensated n-type epitaxial layer, and wherein said n-type epitaxial layer forms a conductive surface that moderates the current crowding that would otherwise occur about said contact to said n-type epitaxial layer, and in which said diode produces a peak emission at a wavelength of between about 475 and 480 nanometers with a spectral half width at peak wavelength of no more than about 50 nanometers.