LED lamps

• US 20110241062A1
• Filed: 04/25/2011
• Published: 10/06/2011
• Est. Priority Date: 11/19/1997
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Epistar Corporation
• Inventors: Salam, Hassan P. A.
• Granted Patent: US 8,399,903 B2
• Time in Patent Office: Days
• US Class Current: 257/99
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 25/0756 Stacked arrangements of devices
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/382 the electrode extending partially in or entirely through the semiconductor body
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/64 Heat extraction or cooling elements

Abstract

A high power LED lamp has a GaN chip placed over an AlGaInP chip. A reflector is placed between the two chips. Each of the chips has trenches diverting light for output. The chip pair can be arranged to produce white light having a spectral distribution in the red to blue region that is close to that of daylight. Also, the chip pair can be used to provide an RGB lamp or a red-amber-green traffic lamp. The active regions of both chips can be less than 50 microns away from a heat sink.

Claims

1-46. -46. (canceled)

47. An LED lamp for producing incoherent visible light comprising:

an LED semiconductor structure comprising an n-layer and a p-layer overlying most of the n-layer;

first and second terminals;

a plurality of spaced conductors on said LED semiconductor structure, each for energizing an associated underlying portion of said n-layer, the associated underlying portion being electrically common to neighboring light-generating portions of the semiconductor structure that are on opposite sides of the spaced conductor;

more than one of said plurality of spaced conductors being connected to said first terminal; and

wherein a light-generating portion of the semiconductor structure extends continuously from a vicinity of one of said spaced conductors to a vicinity of another of said spaced conductors, as viewed normal to said layers, and

wherein for each of a plurality of said spaced conductors there is an adjacent light-generating portion of the semiconductor structure that extends from one side of the spaced conductor to an opposite side of the spaced conductor, and

wherein, for each of at least two of said plurality of spaced conductors, p-layer parts of neighbouring light generating portions of the semiconductor structure that are on opposite sides of the spaced conductor are connected to said second terminal.

48. The LED lamp according to claim 47, wherein said semiconductor structure has four light-generating outer corners as viewed normal to said layers;

each devoid of conductor that energizes the n-layer.

49. The LED lamp according to claim 47, wherein said p-layer is a single sheet that extends to four outer sides of said semiconductor structure.

50. The LED lamp according to claim 47, wherein said interconnecting conductor is metallic.

51. The LED lamp according to claim 47, wherein said n-layer has a plurality of oblique surfaces positioned between a pair of said metallic conductors as viewed normal to said n-layer, each of said oblique surfaces being in contact with non-semiconductor material and oblique to a plane that is generally parallel to said n layer.

52. The LED lamp according to claim 51, wherein said non-semiconductor material is light-passing.

53. The LED according to claim 47, wherein said spaced conductors are metallic.

54. The LED lamp according to claim 47, wherein there is conductor contacting substantially all of the p-layer.

55. The LED lamp according to claim 48, wherein said semiconductor structure has been formed over sapphire.

56. An LED lamp for producing incoherent visible light comprising:

an LED semiconductor structure comprising an n-layer and a p-layer overlying most of the n-layer;

first and second terminals;

a plurality of spaced conductors on said LED semiconductor structure, each for energizing an associated underlying portion of said n-layer, the associated underlying portion being electrically common to neighboring light-generating portions of the semiconductor structure that are on opposite sides of the spaced conductor;

more than one of said plurality of spaced conductors being connected to said first terminal; and

wherein a light-generating portion of the semiconductor structure lies between a pair of said spaced conductors as viewed normal to said layers, and

wherein, for each of at least two of said plurality of spaced conductors, p-layer parts of neighboring light generating portions of the semiconductor structure that are on opposite sides of the spaced conductor are connected to said second terminal, and

wherein the semiconductor structure has LED portions thereof that are connected in series.

57. The LED lamp according to claim 56, wherein said n-layer has a plurality of oblique surfaces positioned between a pair of said metallic conductors as viewed normal to said n-layer, each of said oblique surfaces being in contact with non-semiconductor material and oblique to a plane that is generally parallel to said n layer.