Led lamps

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.

What is claimed is: 
     
         1 . A light-emitting device, comprising:
 a first semiconductor layer;   a terminal formed on the first semiconductor layer and having a first edge, a first side and a second side opposite to the first side; and   a second semiconductor layer facing the first side and the second side, and having a second edge and a third edge substantially aligned with the first edge.   
     
     
         2 . The light-emitting device of  claim 1 , further comprising a trench formed on the first semiconductor layer. 
     
     
         3 . The light-emitting device of  claim 1 , further comprising a conductor track connected to the terminal. 
     
     
         4 . The light-emitting device of  claim 1 , further comprising a substrate connected to the first semiconductor layer and transparent to a light from the first semiconductor layer. 
     
     
         5 . The light-emitting device of  claim 1 , further comprising a support and a reflector formed between the support and the first semiconductor layer. 
     
     
         6 . The light-emitting device of  claim 1 , further comprising a translucent material formed on the second semiconductor layer and having a refractive index of less than 2.5. 
     
     
         7 . The light-emitting device of  claim 1 , further comprising a fuse on the second semiconductor layer. 
     
     
         8 . The light-emitting device of  claim 1 , further comprising a sheet formed on the second semiconductor layer. 
     
     
         9 . The light-emitting device of  claim 8 , wherein the sheet is transparent to a light from the second semiconductor layer. 
     
     
         10 . The light-emitting device of  claim 8 , wherein the sheet comprises a through-hole corresponding to the terminal. 
     
     
         11 . A light-emitting device, comprising:
 a first semiconductor layer;   a second semiconductor layer formed on the first semiconductor layer and having a first side surface;   a first terminal formed on the first semiconductor layer and having a second side surface substantially coplanar with the first side surface;   a second terminal formed on the second semiconductor layer; and   a conductor track having a first portion connected to the first terminal or the second terminal, and a second portion distant from the first portion.   
     
     
         12 . The light-emitting device of  claim 11 , wherein the second semiconductor layer further comprises a third side surface substantially coplanar with the second side surface. 
     
     
         13 . The light-emitting device of  claim 1 , further comprising a trench formed on the first semiconductor layer and having an inclined sidewall. 
     
     
         14 . The light-emitting device of  claim 11 , further comprising a substrate connected to the first semiconductor layer and transparent to a light from the first semiconductor layer. 
     
     
         15 . The light-emitting device of  claim 11 , further comprising a support and a reflector formed between the support and the first semiconductor layer. 
     
     
         16 . The light-emitting device of  claim 11 , further comprising a translucent material formed on the second semiconductor layer and having a refractive index of less than 2.5. 
     
     
         17 . The light-emitting device of  claim 11 , further comprising a fuse on the second semiconductor layer. 
     
     
         18 . The light-emitting device of  claim 11 , further comprising a sheet formed on the second semiconductor layer. 
     
     
         19 . The light-emitting device of  claim 18 , wherein the sheet is transparent to a light from the second semiconductor layer. 
     
     
         20 . The light-emitting device of  claim 18 , wherein the sheet comprises a through-hole corresponding to the first terminal or the second terminal.