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US 6,720,730 B2Granted
High power led lamp
AssigneeUnisplay S.A.
InventorHassan P A Salam
Life of this patent
Estimating the term…
Abstract
A high-power LED lamp uses an LED chip that can be larger than 1 mm square. The chip has trenches that can convert light trapped in the semiconductor into light that passes through a major surface of the chip. The trenches include light-reflecting tracks joined to a chip terminal and feeding a semiconductor layer. The chip can have triangular light emitting elements that improve light extraction from the semiconductor. The elements can be fused, resulting in improved manufacture yield of chips. A 25 watt single chip lamp with a heat sink very close to the active region is described.
Claims100
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising a lower semiconductor layer having a lower face thereof and an upper semiconductor layer having an upper face thereof, said lower and upper semiconductor layers forming a diode and an active region between said layers generating light, said structure having outer side faces (25) surrounding the structure and a plane generally parallel to said lower face defining a reference plane;
- means harvesting vertical light from said active region;
- at least one metal conductor on said semiconductor structure electrically connected with said upper semiconductor layer;
- a plurality of cavities in said semiconductor structure, each cavity extending from said upper face into said semiconductor structure and each containing a metal part that is in electrical contact with said lower semiconductor layer and that is distant from said outer side faces;
- said semiconductor structure being arranged to have several light-extraction surfaces for enhancing release of light from the semiconductor structure, said light-extraction surfaces being distant from said outer side faces and inclined to said reference plane, LED light propagating in the semiconductor structure being diverted at said light-extraction surfaces;
- and
- electrical interconnection for causing the metal parts in said cavities to pass current together when the lamp is turned on.
4 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising a lower semiconductor layer and an upper semiconductor layer, said lower and upper semiconductor layers forming a diode and an active region between said layers generating light, said structure having outer side faces surrounding the structure;
- LED portions within said semiconductor structure, each LED portion provided with an associated conductor for energizing the portion and an associated electrical link (71) in series with the associated conductor, some of said LED portions being faulty and having their associated links deliberately disrupted;
- electrical connections for energizing several of said LED portions together;
- and
- wherein said semiconductor structure has light-extraction surfaces arranged for harvesting light from said semiconductor structure, said light-extraction surfaces being distributed distant from said outer side faces and being inclined to said active region, light generated in the semiconductor structure being diverted at said light-extraction surfaces.
2 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising:
- a lower semiconductor layer having a lower face thereof;
- an upper semiconductor layer grown over said lower semiconductor layer and having an upper face thereof, said lower and upper semiconductor layers forming a diode;
- and an active region between said layers generating light a substantial proportion of which propagates parallel to said active region guided by internal reflections at said upper and lower faces, said structure having outer side faces surrounding the structure;
- a conductor layer in electrical contact with substantially all of the top of said upper semiconductor layer;
- means harvesting vertical light from said active region;
- a plurality of spaced-apart conductor parts distributed about the semiconductor structure, each of said conductor parts being in electrical contact with said lower semiconductor layer and positioned between light generating portions of said semiconductor structure as viewed normal to said layers;
- electrical connection for causing said conductor parts to pass current to said lower semiconductor layer together when the lamp is turned on;
- and
- wherein said semiconductor structure is arranged to have several light-extraction surfaces for release of light that is generated under said conductor layer and guided by said reflections, said light-extraction surfaces being distant from said outer side faces, inclined to said active region, and each meeting at least one of said lower and upper faces.
7 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising:
- a lower semiconductor layer having a lower face thereof;
- an upper semiconductor layer grown over said lower semiconductor layer and having an upper face thereof, said lower and upper semiconductor layers forming a diode;
- and an active region between said layers generating light a substantial proportion of which propagates parallel to said active region guided by internal reflections at said upper and lower faces, said structure having outer side faces surrounding the structure;
- a layer of material translucent to visible light and of lower refractive index than said lower semiconductor layer below the lower semiconductor layer, the translucent layer acting as a reflector for said guided light;
- a semiconductor substrate of higher refractive index than said layer of translucent material below the layer of translucent material, the substrate passing vertical light from said active region;
- a conductor layer covering and in electrical contact with said upper semiconductor layer;
- a plurality of spaced-apart opaque conductors on said semiconductor structure for energizing one of said upper and lower semiconductor layers, at least one of the opaque conductors appearing between light-generating portions of said semiconductor structure as viewed normal to said reference plane;
- electrical connection causing said opaque conductors to pass current to said semiconductor structure together when the lamp is turned on;
- and
- wherein vertical light from said active region passes between a pair of said opaque conductors and wherein said semiconductor structure is arranged to have several light extraction surfaces for release of said guided light from the semiconductor structure, said light-extraction surfaces being distant from said outer side faces and inclined to said reference plane for diverting said guided light for output from the semiconductor structure.
8 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising a lower semiconductor layer and an upper semiconductor layer, said lower and upper semiconductor layers forming a diode and an active region between said layers generating light, said structure having outer side faces surrounding the structure;
- LED portions within said semiconductor structure each having an anode and a cathode, the cathode of one of of the portions being metallically connected to the anode of another of the LED portions;
- electrical connections for energizing several of said LED portions together;
- and
- wherein said semiconductor structure has light-extraction surfaces arranged for harvesting light from said semiconductor structure, said light-extraction surfaces being distributed distant from said outer side faces and being inclined to said active region, light generated in the semiconductor structure being diverted at said light-extraction surfaces.
2 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising:
- a lower semiconductor layer having a lower face thereof;
- an upper semiconductor layer having an upper face thereof, said lower and upper semiconductor layers forming a diode;
- and an active region between said layers generating light, a plane generally parallel to said lower face defining a reference plane;
- means harvesting vertical light from said active region;
- a plurality of opaque conductor parts in electrical contact with said upper semiconductor layer;
- a plurality of grooves provided in said semiconductor structure for light-extraction, each having a light-emitting side wall that meets said upper face and that is inclined to the upper face by an obtuse angle measures through semiconductor;
- each of the grooves containing a metallic reflector arranged for redirecting light emanating from the light emitting side wall;
- and
- electrical connection for causing currents to be fed to said upper semiconductor layer via said opaque conductor parts when the lamp is turned on.
7 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising:
- a lower semiconductor layer having a lower face thereof;
- an upper semiconductor layer having an upper face thereof, said lower and upper semiconductor layers forming a diode;
- and an active region between said layers generating light, a plane generally parallel to said lower face defining a reference plane;
- means harvesting vertical light from said active region;
- a plurality of opaque conductor parts in electrical contact with said upper semiconductor layer and between which light passes;
- a plurality of grooves provided in said semiconductor structure for light-extraction, each of the grooves having a light emitting side wall and containing an associated metallic reflector that reflects some rays from the light emitting wall at least twice successively;
- and
- electrical connection for causing currents to be fed to said upper semiconductor layer via said opaque conductor parts when the lamp is turned on.
6 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising:
- a lower semiconductor layer having a lower face thereof;
- an upper semiconductor layer having an upper face thereof, said lower and upper semiconductor layers forming a diode;
- and an active region between said layers generating light;
- means harvesting vertical light from said active region;
- a plurality of opaque conductor parts in electrical contact with said upper semiconductor layer and between which light passes;
- a plurality of light-extraction grooves excavated in said semiconductor structure each having a side wall that emits light and each containing a metallic reflector for deflecting the emitted light;
- and
- electrical connection for causing currents to be fed to said upper semiconductor layer via said opaque conductor parts when the lamp is turned on.
6 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising:
- a lower semiconductor layer having a lower face thereof;
- an upper semiconductor layer having an upper face thereof, said lower and upper semiconductor layers forming a diode;
- and an active region between said layers generating light;
- means harvesting vertical light from said active region;
- a plurality of opaque conductor parts in electrical contact with said upper semiconductor layer and between which light from said active region passes;
- a plurality of light-extracting trenches in said semiconductor structure, at least one of the trenches being inclined to another of the trenches by an acute angle;
- and
- electrical connection for causing currents to be fed to said upper semiconductor layer via said opaque conductor parts when the lamp is turned on.
6 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising:
- a lower semiconductor layer having a substantially flat lower face thereof;
- an upper semiconductor layer grown over said lower semiconductor layer and having a substantially flat upper face thereof, said lower and upper semiconductor layers forming a diode;
- and an active region between said layers generating light a substantial proportion of which propagates parallel to said active region guided by internal reflections at said upper and lower faces, said structure having outer side faces surrounding the structure;
- a conductor layer in electrical contact with substantially all of the top of said upper semiconductor layer;
- at least one metal conductor electrically in contact with an underlying portion of said lower semiconductor layer;
- means harvesting upward and downward vertical light from said active region;
- and
- wherein said semiconductor structure is arranged to have several light-extraction surfaces distributed about the semiconductor structure for release of said guided light from the semiconductor structure, said light-extraction surfaces being distant from said outer side faces, interfacing with a translucent non-semiconductor medium, meeting at least one of said upper and lower faces and inclined to said upper face.
6 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising:
- a lower semiconductor layer having a lower face thereof;
- an upper semiconductor layer grown over said lower semiconductor layer and having an upper face thereof, said lower and upper semiconductor layers forming a diode;
- and an active region between said layers generating light a substantial proportion of which propagates parallel to said active region guided by internal reflections at said upper and lower faces, said structure having outer side faces surrounding the structure;
- a conductor layer in electrical contact with substantially all of the top of said upper semiconductor layer;
- at least one metal conductor electrically in contact with an underlying portion of said lower semiconductor layer;
- means harvesting vertical light from said active region;
- and
- wherein said semiconductor structure has a plurality of cavities distributed about the structure for release of the guided light;
- each of the cavities extending down from said upper face, terminating at a floor that is below said active region, and containing a non-semiconductor medium;
- side walls of the cavities diverting said guided light.
8 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising:
- a lower semiconductor layer having a lower face thereof;
- an upper semiconductor layer having an upper face thereof, said lower and upper semiconductor layers forming a diode;
- and an active region between said layers generating light;
- said structure having an outer side faces surrounding the structure;
- means harvesting vertical light from said active region;
- at least one conductor in electrical contact with said lower semiconductor layer;
- a conductor layer covering and in electrical contact with said upper semiconductor layer;
- thin light-passing dielectric material covering said conductor layer;
- an opaque reflector covering said light-passing dielectric material;
- and
- wherein said semiconductor structure is formed to have light-diverting surfaces distributed about the structure for release of light from the semiconductor structure, each distant from said side faces, inclined to said semiconductor layers, and meeting at least one of said upper and lower faces.
9 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising:
- a lower semiconductor layer having a lower face thereof and an upper semiconductor layer having an upper face thereof, said lower and upper semiconductor layers forming a diode;
- and an active region between said layers generating light;
- distributed opaque conductors each in electrical contact with said lower semiconductor layer and each positioned between light generating parts of said structure as viewed normal to said active region;
- reflector means at said upper face reflective to light from said active region incident thereon at 45 degrees;
- and
- wherein said semiconductor structure has several light-generating portions at least partly separated from each other by light-diverting surfaces that extend from said upper face into the lower semiconductor layer, at least one of the light-diverting surfaces being at an obtuse angle to said upper face measured through semiconductor, and each of said light-diverting surfaces deflecting light that has been generated by an associated portion of said active region and reflected by said reflector means, the deflected light striking said lower face on its way to contributing to light output from the lamp;
- wherein each of the LED portions has a conductor part thereon for energizing the upper semiconductor layer,
- wherein upward and downward light generated in said portions are harvested;
- and
- wherein interconnection is provided for causing currents to flow through said conductor parts and said opaque conductors together when the lamp is turned on.
8 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising a lower semiconductor layer having a lower face thereof and an upper semiconductor layer having an upper face thereof, said lower and upper semiconductor layers forming a diode and an active region between said layers generating light, said structure having outer side faces surrounding the structure and a plane generally parallel to said lower face defining a reference plane;
- means harvesting upward and downward vertical light from said active region;
- at least one metal conductor on said semiconductor structure electrically connected with said upper semiconductor layer;
- a plurality of spaced-apart conductors on said semiconductor structure each for energizing an associated underlying portion of said lower semiconductor layer and each being distant from said outer side faces and positioned between light generating portions of said semiconductor structure as viewed normal to said reference plane;
- said semiconductor structure being arranged to have several light-extraction surfaces distributed about the semiconductor structure for enhancing release of light from the semiconductor structure, the light-extraction surfaces being distant from said outer side faces and inclined to said reference plane;
- and
- electrical connection for causing said spaced-apart conductors to pass current to said lower semiconductor layer together when the lamp is turned on.
4 more elements
An LED lamp for generating incoherent visible light, comprising:
- an inorganic semiconductor structure comprising a lower semiconductor layer having a lower face thereof and an upper semiconductor layer having an upper face thereof, said lower and upper semiconductor layers forming a diode and an active region between said layers generating light, said structure having outer side faces surrounding the structure and a plane generally parallel to said lower face defining a reference plane;
- means harvesting upward and downward vertical light from said active region;
- a conductor layer covering and in electrical contact with said upper semiconductor layer;
- a plurality of trenches in said semiconductor structure each extending from said upper face into said semiconductor structure and each containing a metal track at least part of which is in electrical contact with said lower semiconductor layer;
- said semiconductor structure having several light-extraction surfaces distributed about the semiconductor structure for enhancing release of light from the semiconductor structure, said light-extraction surfaces being distant from said outer side faces and inclined to said reference plane, LED light propagating in the semiconductor structure being diverted at said light-extraction surfaces;
- and
- electrical connection for causing said tracks to pass current together when the lamp is turned on.
4 more elements
An LED lamp according to 82 including reflectors in said trenches that are oblique to said reference plane.
Dependencies are inferred from the claim text.