Incandescent light energy conversion with reduced infrared emission

Incandescent light emission apparatus comprising in combination:

• an energy conversion body member including at least one radiant energy emission surface, and additionally including at least a first region including said at least one radiant energy emission surface, said first region including at least a first end and a second end, said first region extending between said first end and said second end, and at least a second region having different properties from said first region, said second region being adjacent to said first region, said second region including at least a first end and a second end, said second region extending between said first end and said second end, said first end of said first region adjacent said first end of said second region and said second end of said first region adjacent said second end of said second region,
• at least said second region of said body member being adapted to suppress light energy in the infra red spectrum range emitted through said radiant energy emission surface, and
• means applying to said body at least one of heat and electricity operable to produce emission through said radiant energy emission surface, wherein said means applying to said body at least one of heat and electricity includes at least one of:
• (1) electrical contacts in contact with both said first end and said second end of said first region, for current to pass therebetween, (2) electrical contacts in contact with both said first end and said second end of said second layer, for current to pass therebetween, and (3) an external heating source for heating said semiconductor body to cause incandescent light to be emitted by said radiant energy emission surface.

Incandescent light emission apparatus comprising in combination:

• a semiconductor body of a material taken from the group of semiconductors having a band gap greater than about 2 eV,
• said body having at least one radiant energy transfer surface,
• said body having at least at least a first thin lightly doped layer adjacent said energy transfer surface adapted for suppression of the free carrier absorption property, said body additionally including at least a second doped layer adjacent said first layer, said second layer distal from said energy transfer surface, said first layer being doped more heavily than said second layer, said second layer additionally adapted for suppression of the free carrier absorption property,
• wherein said first thin lightly doped layer adjacent said energy transfer surface includes first and second opposing surfaces substantially in parallel with each other, said energy transfer surface extending between said first and second opposing surfaces and perpendicular to said first and second opposing surfaces,
• wherein said second doped layer adjacent said first layer includes first and second opposing surfaces substantially in parallel with each other, said second doped layer extending between said first and second opposing surfaces, said first opposing surface of said first layer adjacent said first opposing surface of said second layer and said second opposing surface of said second layer adjacent said second opposing surface of said second layer,
• means heating at least said first layer sufficient to produce incandescent emission through said transfer surface, said means including at least first and second electrical contacts in electrical contact with at least one of either:
• (1) both said first and said second opposing faces of said first layer, for current to pass therebetween, and (2) both said first and said second opposing faces of said second layer, for current to pass therebetween.

Incandescent light emission apparatus comprising in combination:

• a semiconductor body of a material taken from the group of semiconductors
• having a band gap greater than 2 eV,
• said body having at least one radiant energy transfer surface,
• said body having at least a thin lightly doped layer adjacent said energy transfer surface and adapted for suppression of the free carrier absorption property, said layer having at least a first end including a first electrical contact proximal to said first end and a second end including a second electrical contact proximal to said second end, said layer being located between said first and second ends,
• means heating said layer sufficient to produce incandescent emission through said transfer surface,
• wherein said means heating said layer includes passing electric current through said layer between said first contact and said second contact,
• wherein said semiconductor body is of a material taken from the group of cubic silicon carbide (3CSiC), hexagonal silicon carbide (.alpha.SiC) and aluminum nitride (AlN), and
• wherein said body is of cubic silicon carbide and wherein said layer is doped to about 10.sup.17 atoms/cc and is about 500-1000 .ANG. thick and is supported by a layer of said silicon carbide doped to about 10.sup.15 atoms/cc.

An apparatus for the conversion of energy between at least one of heat and electricity and incandescent light comprising in combination:

• an energy converter body member including a semiconductor body with at least one radiant energy transfer surface and at least one region for the transfer of at least one of heat and electricity, said first region comprising doped 3C-SiC semiconductor material, said region including a first end and a second end, said radiant energy transfer surface located between said first and second ends,
• said semiconductor energy converter body member having a band gap greater than about 2 eV,
• said semiconductor energy converter body having at least one layer adjacent to and essentially parallel with said radiant energy transfer surface in which the free carrier absorption property of said semiconductor is suppressed, and,
• means transferring at least one of heat and electricity at least to said layer adjacent to said energy transfer surface, wherein said means transferring at least one of heat and electricity includes at least one of:
• (1) electrical contacts in contact with both said first end and said second end of said layer adjacent to said energy transfer surface, and (2) an external heating source for heating said semiconductor body to cause incandescent light to be emitted by said radiant energy emission surface.