CN208478368U - A kind of light emitting diode - Google Patents

Abstract

It includes the first semiconductor layer, luminescent layer, the second semiconductor layer and light-emitting surface that the utility model, which provides a kind of light emitting diode, current expansion item positioned at light-emitting surface surface, light-emitting surface below current expansion item includes platform and the etching roughening treatment face of surrounding, it is characterized by: being less than or equal to 0.5um along the width that surrounding light-emitting surface below extension item forms platform, the etch depth of light-emitting surface be greater than or equal to 0.7um, can effectively guarantee base part luminescent layer light-out effect and extension item lower section without departing from.

Description

A kind of light emitting diode

Technical field

The utility model relates to a kind of light emitting diodes, relate more specifically to a kind of electrode structure of light emitting diode.

Background technique

In existing LED structure, electrode includes bonding wire electrode and extension strip electrode, wherein to keep light extraction efficiency more preferable, It can be by the light-emitting surface roughing in surface of electrode extension side.Being roughened common method is chemical wet, iso due to etching Feature, therefore can be also etched below the extension item of light output surface.Conventional electrode is metal electrode or transparent semiconductor electricity Pole.Metal electrode can more be widely used since electric conductivity is more preferable, for metal electrode, in order to guarantee the light-emitting surface of lower section Lighting area maximizes, and electrode extension item designs thinner, and micron order or submicron order erode to one in etching process In the case where depthkeeping degree, it also will appear lateral etches depth accordingly, if lateral etches are too deep to will lead to extension item and lower section Material layer contacts face is small, and extension item is easily separated from.

Summary of the invention

In order to solve the above-mentioned technical problem, guarantee light-out effect and extension item without departing from, the utility model provide with A kind of lower light emitting diode, including the first semiconductor layer, luminescent layer, the second semiconductor layer and light-emitting surface are located at light-emitting surface table The electrode extension item in face, light-emitting surface are roughening treatment face, and the width of platform is formed along surrounding light-emitting surface below electrode extension item Less than or equal to 0.5um, the etch depth of light-emitting surface roughening treatment is greater than or equal to 0.7um.

Further, the light-emitting surface be the second semiconductor layer or the second semiconductor layer surface current extending or Window layer.

Further, the light-emitting surface is ohmic contact layer.

Further, the electrode be metal electrode, preferably gold, germanium, platinum, copper, aluminium, titanium, nickel, chromium and/or they Metal alloy or metal oxide etc..

Further, the berm width is less than or equal to emission wavelength.

Further, berm width is less than or equal to 0.4 micron, and the more preferably berm width is less than or equal to 0.2 micron.

Further, the electrode extension width is the more preferably described electrode size more than or equal to 1 micron It is 3-20 μm.

Further, the light-emitting surface etch depth is less than the second semiconductor layer or the electricity of the second semiconductor layer surface Flow the thickness of extension layer or window layer thickness or ohmic contact layer.

The beneficial effect of the application is:

The width design of platform is less than or equal to 0.5 micron, more preferably platform by design according to the present utility model Width is less than or equal to 0.4 micron, and more preferably berm width is less than or equal to 0.2 micron, due to ultraviolet common each to feux rouges The luminous glistening light of waves of color light emitting diode is between 0.2-0.8 microns.In order to guarantee current expansion efficiency, preferred electrode extension Strip material is metal material, close to emission wavelength or is less than or equal to the wave that shines by the platform size around electrode extension item It is long, it can effectively guarantee that the light that the luminescent layer below electrode extension item is launched goes out light as far as possible, or can send out in flat surface The diffraction of the third contact of a total solar or lunar eclipse goes out light, to effectively promote light-emitting surface light extraction efficiency.

Preferably, 0.7um is greater than or equal to by longitudinal etch depth on light-emitting surface surface, guarantees that light-emitting surface is roughened journey Degree, improves the light extraction efficiency of light-emitting surface；Guarantee electrode extension item by forming platform along surrounding light-emitting surface below current expansion It can be firmly secured at light-emitting surface, avoiding electrode extension item, there is a phenomenon where be detached from.Design based on the utility model, it is described Electrode width be more than or equal to 1 micron, can be effectively prevented from electrode extension item will not be too thin, and occur electrode be easy it is disconnected It splits, the low problem of current expansion efficiency.

Detailed description of the invention

Fig. 1 is the structural schematic diagram of the light emitting diode of the utility model patent.

Attached drawing is used to provide a further understanding of the present invention, and constitutes part of specification, practical with this Novel embodiment is used to explain the utility model together, does not constitute limitations of the present invention.In addition, attached drawing data are Summary is described, is not drawn to scale.

Specific embodiment

Embodiment 1

Following example discloses a kind of red light-emitting diode with expansion electrode, as shown in Figure 1, include substrate 8, Mirror-reflection articulamentum 7, the first contact layer 5, the first semiconductor layer 4, active layers 3, the second semiconductor layer 2, the second contact layer 1, Electrode extension item 6, wherein electrode structure includes the contact electrode and electrode extension item 6 for Injection Current, the contact electricity The electrode extension item 6 is drawn in pole, and light-emitting surface is the second contact layer.Substrate be preferably the substrate of silicon, specular layer be containing The reflecting layer of the composite material of gold or silver preparation, the preferably reflecting layer of billon, are preferably provided with one layer on specular layer Dielectric layer, dielectric layer are provided with current lead-through hole, and first contact layer is gallium phosphide, GaAs, ITO etc., the present embodiment It is GaAs contact layer with a thickness of 70nm, light emitting region includes that the first semiconductor layer is gallium phosphide, aluminium indium gallium phosphorus, aluminium indium phosphorus etc., master Dynamic layer is aluminium indium phosphorus, gallium aluminium phosphorus phosphorus, gallium phosphide or aluminum gallium arsenide etc., and emission wavelength is the second semiconductor layer between 550-850 nanometers Can for gallium phosphide, aluminium indium gallium phosphorus, aluminium indium phosphorus etc., the first semiconductor layer p-AlInP P-type layer of the present embodiment with a thickness of 0.3um, (AlzGa1-z) 0.5In0.5P active layers are with a thickness of 0.2um, and preferably trap is (Al0.1Ga0.9) 0.5In0.5P, build and are (Al0.65Ga0.35) 0.5In0.5P, launch wavelength is between 620-624nm.Second semiconductor layer is n-AlInP N-type layer With a thickness of 0.3um, the second contact layer is gallium phosphide, GaAs, ITO, AlGaInP etc., and the present embodiment is AlGaInP contact layer With a thickness of 3um.The electrode extension strip material be metal electrode, it is therefore preferable to gold, platinum, copper, aluminium, titanium, nickel, germanium and/or it Metal alloy or metal oxide etc., width is more than or equal to 1 micron, and the present embodiment is preferably AuGe, and the present embodiment is excellent Selecting width dimensions is 7 microns.

The specific production method of electrode be with electrode pattern is lithographically formed, then use ion sputtering, electron beam transpiration or Electric plating method grows electrode, peels off the electrode material layer on photoresist, and remove photoresist and to form electrode, including electrode extension item. The formation of electrode pattern is not limited to which in the present invention.Then make electrode extension item with the means of chemical mechanical grinding (CMP) Thickness be less than 1um.

The mode of light-emitting surface roughening treatment is light-emitting surface spin coating photoresist, then using Partial exposure, baking, development to electricity Pole, which extends, carries out photoresist protection around item, then etched with the mode of wet etching to light-emitting surface.The present embodiment etches molten Liquid is conventional soln: acetic acid, nitric acid, hydrofluoric acid and iodine mixed solution, 25 ~ 60 DEG C of temperature, 20 ~ 120s of time.Concrete operations To apply a layer photoresist in light-emitting surface plate, realize that photoresist part is exposed by reticle plate, in electrode extension item after development Surrounding forms a layer photoresist, so that light-emitting surface is not chemically etched and forms platform around guard electrode extension item.Photoresist Width can pass through the pore size or gap size of the light transmission of reticle plate and carry out conventional control and realize.Specifically engraving method is Prepared corrosive liquid is heated to 40 DEG C, is immersed in corrosive liquid, is taken out after 90s.At once in 25 DEG C of deionizations after taking-up Etch-stop effect is cleaned in water.0.4 μm of width A or so of platform is formed along surrounding below extension item, etch depth B is 1 μm。

In the present embodiment, by the design of longitudinal etch depth, guarantee light-emitting surface roughness, to improve light emission rate. Since platform size is smaller, in the case where capable of guaranteeing light emission rate, electrode can be firmly secured at platform surface, this external electrode The size of circumferential mesas is less than or close to emission wavelength, and diffraction can occur around platform and go out light for some light, promotes light emission rate. The preferably described electrode extension width is the further preferably described electrode extension item more than or equal to 1 micron simultaneously Width is between 3-20 μm, and electrode extension item will not be too thin, can effectively avoid and electrode deposition technique occurs and be difficult to control, electrode holds The problem of easy fracture.

Comparative example

Different from embodiment 1, the berm width around electrode extension item is 1 micron.Light is imported by etching surface Around cover protection extension item, light-out effect will affect in the berm width size that surrounding them is formed, wide platform will lead to Light extraction efficiency is substantially reduced.By testing example and comparative example, the brightness for the light emitting diode that embodiment obtains improves 3%.

Above embodiments only intuitively illustrate that the utility model uses, and are not limitation of the utility model.Specific figure Shape scheme can do various change, as long as belonging to the scope of the utility model protection in each claim limited range.

Claims (10)

1. a kind of light emitting diode, including the first semiconductor layer, luminescent layer, the second semiconductor layer and light-emitting surface are located at light out The electrode extension item on face surface, it is characterised in that: the light-emitting surface below electrode extension item includes the platform of surrounding and etches thick Change process face, is less than or equal to 0.5um along the width that surrounding light-emitting surface below extension item forms platform.

2. light emitting diode according to claim 1, it is characterised in that: include Ohmic contact above the second semiconductor layer Layer, current extending or Window layer, wherein light-emitting surface be the second semiconductor layer by layer on ohmic contact layer, current extending or window Mouth layer.

3. light emitting diode according to claim 1, it is characterised in that: the etch depth of light-emitting surface is greater than or equal to 0.7um。

4. light emitting diode according to claim 1 or 2, it is characterised in that: the electrode extension item is metal material It is made.

5. light emitting diode according to claim 1 or 2, it is characterised in that: the metal of the electrode extension item be gold, Germanium, platinum, copper, aluminium, titanium, nickel, chromium and/or their metal alloy or metal oxide.

6. light emitting diode according to claim 1 or 2, it is characterised in that: electrode extension width is micro- more than or equal to 1 Rice.

7. light emitting diode according to claim 1 or 2, it is characterised in that: electrode extension width is 3-20 microns.

8. light emitting diode according to claim 1 or 2, it is characterised in that: the berm width of electrode extension item is less than hair The emission wavelength of optical diode.

9. light emitting diode according to claim 1 or 2, it is characterised in that: berm width is less than or equal to 0.4 micron.

10. light emitting diode according to claim 1 or 2, it is characterised in that: the etch depth on the light-emitting surface surface Less than the current extending or window layer thickness of the second semiconductor layer or the second semiconductor layer surface or the thickness of ohmic contact layer.