CN101510580A

CN101510580A - LED with current blocking layer

Info

Publication number: CN101510580A
Application number: CNA2009100376413A
Authority: CN
Inventors: 樊邦扬; 叶国光
Original assignee: Heshan Lide Electronic Enterprise Co Ltd
Current assignee: Heshan Lide Electronic Enterprise Co Ltd
Priority date: 2009-03-05
Filing date: 2009-03-05
Publication date: 2009-08-19

Abstract

The invention discloses a light-emitting diode with a current barrier layer; the light-emitting diode comprises a substrate, an n-type semiconductor material layer formed on the front surface of the substrate, a light emitting layer formed on the n-type semiconductor layer, a p-type semiconductor material layer formed on the light emitting layer, a transparent electrode layer formed on the light emitting layer, an anode-metal electrode weld-line layer formed on the transparent electrode layer, a cathode-metal electrode weld-line layer formed on the n-type semiconductor material layer, weld lines formed on the anode-metal electrode weld-line layer and the cathode-metal electrode weld-line layer, and the current barrier layer formed in a corresponding local position below the anode-metal electrode weld-line layer between the transparent electrode layer and the p-type semiconductor material layer. The light-emitting diode utilizes the current barrier layer to reduce the current accumulated below the chip electrode, lowers light absorption by the electrode and increases light emitting efficiency.

Description

A kind of light-emitting diode with current barrier layer

Technical field

The present invention relates to a kind of light emitting semiconductor device, particularly a kind of light-emitting diode with current barrier layer.

Background technology

So-called light-emitting diode (LED) is exactly that the semi-conducting material that will possess direct gap is made the P/N diode, under thermally equilibrated condition, most electronics does not have enough energy to rise to conductive strips, impose forward bias voltage drop again, then electronics can rise to conductive strips, and the original position of electronics on former valence bond band promptly produces the hole.Under suitable bias voltage, electronics, hole just can P/N interface zone (P-N Juction) in conjunction with and luminous, the electric current of power supply can constantly replenish electronics and hole and give N type semiconductor and P type semiconductor, make electronics, hole in conjunction with and luminous being continued carries out.The luminous principle of LED is the combination in electronics and hole, and the energy of electron institute band discharges with the form of light, is called spontaneous radiation.The light that general LED is emitted is to belong to this type.

General traditional LED production method is an epitaxial growth monocrystal material structure on substrate, minus semi-conducting material normally, luminescent layer and eurymeric semi-conducting material, different along with material and structure, the light color that is sent has also had variation, for example gallium nitride is generally used for the material of blue light and green glow, and substrate and material structure have very big difference, bluish-green and purple light is a substrate epitaxial indium gallium N structure with the sapphire of insulation usually, and sapphire is non-conductive, so the blue green light processing procedure is complicated, and positive and negative electrode is all in the front, also will be behind the epitaxial manufacture process through the making of electrode, the etching in negative pole zone, the photoetching of chip surface and cleaning, the detection of the characteristics of luminescence, attenuate cuts into many chip, and then the routing encapsulation.

Because on the light-emitting area of chip, electrode has accounted for very big area, and in general electrode and the transparency electrode design, current density be concentrated in electrode below, cause most of light to result from below the electrode, and general electrode is the material of extinction, so there is very big a part of light all to be absorbed, causes existing light-emitting diode light emission rate not high.

Summary of the invention

The invention provides a kind of light-emitting diode with current barrier layer, comprise substrate, be formed at the n N-type semiconductor N material layer on the front of substrate, be formed at the luminescent layer on the n N-type semiconductor N material layer, be formed at the p N-type semiconductor N material layer on the luminescent layer, be formed at the transparent electrode layer on the p N-type semiconductor N material layer, be formed at the anode metal electrode bonding wire layer on the transparent electrode layer and be formed at cathodic metal electrode bonding wire layer on the n N-type semiconductor N material layer, be formed at anode metal electrode bonding wire layer, bonding wire on the cathodic metal electrode bonding wire layer, between transparent electrode layer and p N-type semiconductor N material layer, on the local location of anode metal electrode bonding wire layer below correspondence, be formed with current barrier layer, the material of described anode metal electrode bonding wire layer and cathodic metal electrode bonding wire layer is Al, Ag, the material of described bonding wire are Cu, Al or Ag.

Because on local location corresponding below the anode metal electrode bonding wire layer, be formed with current barrier layer, so the electric current that flows into transparency electrode can not accumulate in the below of anode metal electrode bonding wire layer, therefore electric current can evenly diffuse throughout on the luminescent layer in addition of anode metal electrode bonding wire layer below, thereby reduce of the absorption of anode metal electrode bonding wire layer to the full extent to light, improved the light emission rate of chip, and owing to adopted Cu line, Al line, Ag line as bonding wire, so reduced manufacturing cost effectively with respect to former employing Au line.

Description of drawings

Fig. 1 is the structural representation of wafer vertical section of the present invention;

Fig. 2 is the front schematic view of wafer of the present invention;

Fig. 3 is a light-emitting diode structure schematic diagram of the present invention;

Fig. 4 forms the vertical section structural representation of high-power chip for the present invention;

Fig. 5 forms the front schematic view of high-power chip for the present invention;

Embodiment

The invention will be further described below in conjunction with drawings and Examples.

With reference to figure 1, Fig. 2, a kind of light-emitting diode with current barrier layer, comprise substrate 1, be formed at the n N-type semiconductor N material layer 2 on the front of substrate 1, be formed at the luminescent layer 3 on the n N-type semiconductor N material layer 2, be formed at the p N-type semiconductor N material layer 4 on the luminescent layer 3, be formed at the transparent electrode layer 6 on the p N-type semiconductor N material layer 4, be formed at anode metal electrode bonding wire layer 81 and the cathodic metal electrode bonding wire layer 82 that is formed on the n N-type semiconductor N material layer 2 on the transparent electrode layer 6, be formed at anode metal electrode bonding wire layer 81, bonding wire 91 on the cathodic metal electrode

bonding wire layer

82,92; Between transparent electrode layer 6 and p N-type semiconductor N material layer 4, on the local location of anode metal electrode bonding wire layer 8 below correspondence, be formed with current barrier layer 5, described anode metal electrode bonding wire layer 81 is Al or Ag with the material of cathodic metal electrode bonding wire layer 82, the material of described

bonding wire

91,92 is Cu, Al or Ag, the material of its solder joint can adopt Al, Ag, Cu, as shown in Figure 3, described

bonding wire

91,92 is electrically connected to conducting bracket 11,12 respectively, conducting bracket is used for being connected with external circuit, again through making light-emitting diode after the encapsulating baking.

Wherein, substrate 1 material is sapphire, silicon, carborundum or gallium nitride, and the material of n N-type semiconductor N material layer 2 is a gallium nitride, and the material of luminescent layer 3 is an indium gallium nitrogen.Be non-ohmic contact between current barrier layer 5 and the p N-type semiconductor N material layer 4, be preferably the insulation contact.The material of described current barrier layer 5 is not its material of extinction metal, for example Al, Ag, TiO ₂, Al ₂O ₃, SiO ₂, Si ₃N ₄Or a kind of or its combination among the ZnO.

In addition, between anode metal electrode bonding wire layer 81 and the transparent electrode layer 6, be provided with anode metal contact electrode layer 71, cathodic metal contact electrode layer 72 between cathodic metal electrode bonding wire layer 82 and the n N-type semiconductor N material layer 2.Described anode metal contact electrode layer 71 is ohmic contact with transparent electrode layer 6 and cathodic metal contact electrode layer 72 with n N-type semiconductor N material layer 2.The material of described anode metal contact electrode layer 71, cathodic metal contact electrode layer 72 is a kind of or its combination among Ti, Ni, Au, Ag, Pt, Cr or the Wu.

Manufacture method of the present invention is, on substrate 1, form n N-type semiconductor N material layer 2, luminescent layer 3 and p N-type semiconductor N material layer 4, then behind subregion etching p N-type semiconductor N material layer 4 and luminescent layer 3 to n N-type semiconductor N material layers 2, do not plating current barrier layer 5 on etching p N-type semiconductor N material layer 4 subregions, on p N-type semiconductor N material layer 4, plate transparent electrode layer 6 then, this transparent electrode layer 6 can cover or not cover current barrier layer 5, on the position of current barrier layer 5, plate anode metal contact electrode layer 71 and anode metal electrode bonding wire layer 81 then, plate cathodic metal contact electrode layer 72 and cathodic metal electrode bonding wire layer 82 in the zone that is etched of n N-type semiconductor N material layer 2, then that chip is solid brilliant, and respectively at anode metal electrode bonding wire layer 81, connect bonding wire 91 on the cathodic metal electrode

bonding wire layer

82,92,

bonding wire

91,92 with conducting bracket 11,12 connect, again through after the encapsulating baking it being made light-emitting diode.

As Fig. 4, shown in Figure 5, the present invention can also become high-power chip with a plurality of above-mentioned light-emitting diode chip for backlight unit serial or parallel connections.

The above is all so that the present invention conveniently to be described, in the spiritual category that does not break away from the present invention's creation, the various simple covert and modification that those skilled in the art did of being familiar with this technology still belongs to protection scope of the present invention.

Claims

1, a kind of light-emitting diode with current barrier layer comprises

Substrate;

Be formed at the n N-type semiconductor N material layer on the front of substrate;

Be formed at the luminescent layer on the n N-type semiconductor N material layer;

Be formed at the p N-type semiconductor N material layer on the luminescent layer;

Be formed at the transparent electrode layer on the p N-type semiconductor N material layer;

Be formed at the anode metal electrode bonding wire layer on the transparent electrode layer and be formed at cathodic metal electrode bonding wire layer on the n N-type semiconductor N material layer;

Be formed at the bonding wire on anode metal electrode bonding wire layer, the cathodic metal electrode bonding wire layer;

It is characterized in that: between transparent electrode layer and p N-type semiconductor N material layer, on the local location of anode metal electrode bonding wire layer below correspondence, be formed with current barrier layer, the material of described anode metal electrode bonding wire layer and cathodic metal electrode bonding wire layer is Al or Ag, and the material of described bonding wire is Cu, Al or Ag.

2, a kind of light-emitting diode with current barrier layer according to claim 1 is characterized in that: between described anode metal electrode bonding wire layer and the transparent electrode layer, be provided with the metal electrode contact layer between cathodic metal electrode bonding wire layer and the n N-type semiconductor N material layer.

3, a kind of light-emitting diode with current barrier layer according to claim 2, it is characterized in that: described metal electrode contact layer and transparent electrode layer are ohmic contact.

4, a kind of light-emitting diode with current barrier layer according to claim 2 is characterized in that: the material of described metal electrode contact layer is a kind of or its combination among Ti, Ni, Au, Ag, Pt, Cr or the Wu.

5, a kind of light-emitting diode with current barrier layer according to claim 1 is characterized in that: described current barrier layer is that non-ohmic contact or insulation contact with p N-type semiconductor N material layer.

6, a kind of light-emitting diode with current barrier layer according to claim 1 is characterized in that: the layer material of described current blocking is extinction metal not.

7, a kind of light-emitting diode with current barrier layer according to claim 6, it is characterized in that: the material of described current barrier layer is Al, Ag, TiO ₂, Al ₂O ₃, SiO ₂, SiXN ₄Or a kind of or its combination among the ZnO.