Light-emitting diode and the manufacturing method of the same

Abstract

The specification discloses a light-emitting diode and the corresponding manufacturing method. A GaN thick film with a slant surface is formed on the surface of a substrate. An epitaxial slant surface is naturally formed using the properties of the GaN epitaxy. An LED structure is grown on the GaN thick film to form an LED device. This disclosed method and device can simplify the manufacturing process. The invention further uses the GaN thick film epitaxial property to make various kinds of LED chips with multiple slant surfaces and different structures. Since the surface area for emitting light on the chip increases and the multiple slant surfaces reduce the chances of total internal reflections, the light emission efficiency of the invention is much better than the prior art.

1 . An LED device comprising: 
 a GaN thick film with a slant surface formed using the epitaxial property; and    an LED structure, which contains an n-GaN-series III-V family compound and a p-GaN-series III-V family compound;    wherein the n-GaN-series III-V family compound is stacked on the surface of the GaN thick film and in electrical communications with an n-type low-resistance ohmic contact electrode, and the p-GaN-series III-V family compound is in electrical communications with a p-type low-resistance ohmic contact electrode for providing a forward bias.    
   
   
       2 . The LED device of  claim 1 , further including the GaN thick film with a slant surface formed on a surface of the substrate by epitaxy.  
   
   
       3 . The LED device of  claim 2 , wherein the substrate is selected from the group consisting of sapphire, SiC, Si, GaAs, AlN, LiGaO 2  and LiAlO 2  substrates.  
   
   
       4 . The LED device of  claim 1 , wherein the GaN thick film is an Al X Ga (1−X−Y) In Y N thick film, where 0≦X<1, 0≦Y<1 and 0≦X+Y<1.  
   
   
       5 . The LED device of  claim 1 , wherein the thickness of the GaN thick film is above 20 μm and its inner diameter of the pattern is greater than 150 μm.  
   
   
       6 . The LED device of  claim 1 , wherein the pattern has a shape selected from the group consisting of a quadrilateral, a hexagon and a circle.  
   
   
       7 . The LED device of  claim 1 , wherein the bottom surface and the side surface of the GaN thick film subtend an angle α, where 43°≦α≦62°.  
   
   
       8 . The LED device of  claim 1 , wherein the n-type low-resistance ohmic contact electrode and the p-type low-resistance ohmic contact electrode are formed on the same side of the GaN thick film, the p-type low-resistance ohmic contact electrode being formed on the GaN thick film of the p-GaN-series III-V family compound and the n-type low-resistance ohmic contact electrode being formed on the surface of the p-GaN-series III-V family compound.  
   
   
       9 . The LED device of  claim 1 , wherein the LED structure further contains an active layer between the n-GaN-series III-V family compound and the p-GaN-series III-V family compound as a light-emitting region.  
   
   
       10 . The LED device of  claim 1 , wherein the active layer is selected from the group consisting of a double heterostructure (DH), a single-quantum well (SQW) or a multiple-quantum well (MQW).