CN208173615U - A kind of light emitting diode - Google Patents

Abstract

It includes the first semiconductor layer, luminescent layer, the second semiconductor layer that the utility model, which provides a kind of following light emitting diode, second semiconductor layer side surface has light-emitting surface, current expansion item positioned at light-emitting surface surface, light-emitting surface around below current expansion item is the roughening treatment face that etching is formed, it is characterised in that：The lateral etches of electrode extension lower inner are formed along the light-emitting surface of surrounding below electrode extension item, lateral etches depth is more than or equal to 1 micron between 0-0.8um, longitudinal etch depth of light-emitting surface.Guarantee 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 light-emitting surface roughing in surface.Being roughened common method is chemical wet, due to etching iso feature, in light out It will appear lateral etches around below the extension item on surface, in the case that longitudinal etching erodes to certain depth, below extension item Surrounding also will appear the lateral etches of same depth, if the too deep layer sequence that will lead to extension item and lower section of lateral etches Contact surface is small, and current expansion efficiency is low, as shown in Figure 1.While the light-emitting surface lighting area in order to guarantee lower section, current expansion item Thinner, the usual micron order of meeting, the too deep extension item that will lead to of lateral etches are easily separated from light-emitting surface.

Utility model content

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 substrate, the first semiconductor layer, luminescent layer, the second semiconductor layer, current extending on substrate And light-emitting surface, the current expansion item positioned at light-emitting surface surface, light-emitting surface are roughening treatment face, it is characterised in that：Along extension Light-emitting surface around below item forms the lateral etches to extension lower inner, and the depth of lateral etches is between 0-0.8um, out Longitudinal etch depth of smooth surface is more than or equal to 1 micron.

It is highly preferred that second semiconductor layer side has ohmic contact layer or current extending or Window layer, ohm Contact layer or current extending or Window layer are roughening treatment face.

It is highly preferred that the electrode extension item includes following one metal：Gold, platinum, copper, aluminium, titanium, nickel, chromium or described The combination of metal alloy or metal oxide.

It is highly preferred that along extension item below surrounding light-emitting surface lateral etches width between 0-0.3,0.3-0.5um, Between 0.5-0.8um.

It is highly preferred that the electrode extension width is 3 ~ 20um.

The beneficial effect of the application is：

Design according to the present utility model can by forming lateral etches along surrounding window layer below current expansion The lighting area for increasing light-emitting surface, to improve light emission rate.It is micro- to be greater than 1 by current extending or the etch depth of Window layer Rice, guarantees the coarsening rate of light-emitting surface, improves the light extraction efficiency of light-emitting surface.Along extension item below around current extending or Window layer forms the width of lateral etches between 0-0.8 microns, can effectively guarantee that electrode can be firmly secured at light-emitting surface Surface.The electrode extension width is 3 ~ 20um, and can be effectively prevented from electrode extension item will not be too thin, ensure that ESD Performance effectively avoids the occurrence of electrode simultaneously and is easily broken off, the low problem of current expansion efficiency.

Other features and advantages of the utility model will illustrate in the following description, also, partly from specification In become apparent, or understood and implementing the utility model.The purpose of this utility model and other advantages can pass through Specifically noted structure is achieved and obtained in the specification, claims and drawings.

Detailed description of the invention

Fig. 1 is the scanning electron microscope (SEM) photograph after existing light emitting surface of light emitting diode roughening treatment.

Fig. 2 a, 2b are the structural schematic diagram before the roughening treatment of the light emitting diode of the utility model patent.

Fig. 3 is the structural schematic diagram after the light-emitting surface roughening treatment of the light emitting diode of the utility model patent.

Fig. 4 is the scanning electron microscope (SEM) photograph after the light-emitting surface roughening treatment 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

Fig. 2 is the structural schematic diagram before the roughening treatment of the light emitting diode of the utility model patent.The present embodiment provides A kind of following light emitting diode includes：Ohmic contact layer 1 be N-GaAs, the second semiconductor layer 2 be GaP, AlGaInP or AlInP, the present embodiment AlGaInP, active layers 3 be AlGaInP, emission wavelength 620nm, the first semiconductor layer 4 be GaP, AlGaInP or AlInP, the present embodiment AlGaInP, current extending 5 are P-GaP, and current expansion item 6 is located at ohmic contact layer Top, mirror-reflection articulamentum 7, substrate 8.Current extending or ohmic contact layer are conducive to current expansion or out light.Ohmic contact Layer can also be substituted or be applied in combination by transparency conducting layers such as ITO, GTO, to improve the light extraction efficiency of electrode.In other implementations In example, roughening treatment longitudinal direction etch depth should be less than the thickness of ohmic contact layer or current extending or Window layer, work as light-emitting surface For the second semiconductor layer, thickness should be less than the thickness of the second semiconductor layer, to avoid light-emitting surface too deep at overetch, destroy The problem of epitaxial layer light emitting structure of light emitting diode, luminous efficiency reduces.

The ohmic contact layer 1 of the present embodiment is light-emitting surface, and light-emitting surface surface passes through the production electrode such as sputtering, vapor deposition, plating Item 6 is extended, 6 material of electrode extension item is gold, platinum, copper, aluminium, titanium, nickel, germanium, chromium or their metal alloy or metal Oxide etc., the present embodiment are preferably gold germanium electrode, and preferable width is 7 microns.

The preparation process of light emitting diode for obtaining the utility model is：First in growth substrates, the present embodiment is arsenic Gallium includes ohmic contact layer 1, the second semiconductor layer 2, active layers 3, the first semiconductor layer 4 and electricity by MOCVD epitaxy growth The epitaxial structure of extension layer 5 is flowed, 5 surface of current extending makes mirror-reflection articulamentum 7, is bonded substrate 8, and the back side makes metal Electrode removes growth substrates, and prepares electrode extension item in 1 side of ohmic contact layer, and roughening treatment obtains light-emitting surface.

The technique of light-emitting surface roughening treatment is chemical etching, as shown in Figure 2 a, coats one layer on the surface of ohmic contact layer 1 Photoresist forms a layer photoresist 9, as shown in Figure 2 b then by exposing, toasting, after development around electrode extension item.After The continuous part to light-emitting surface exposure uses the mode of wet etching to continue roughening etching to form roughening face, as shown in Figure 3. Photoresist is conventional use of positive-working photoresist, selects the optical cement coefficient of viscosity>0.5pas, and used insoluble in light-emitting surface roughening treatment Chemical etching liquor, remove remaining photoresist after the completion of etching.The present embodiment is that common chemical etching liquor is acetic acid, nitre The mixed liquor of acid, hydrofluoric acid and iodine, 25 ~ 60 DEG C of temperature, 20 ~ 120s of time.It is attached to around electrode extension item by photoresist Form certain thickness barrier layer, slow down the lateral etches below electrode extension item, removing residual glue with a thickness of 0.3 micron or more, Specific thickness is controlled by spin-coating time.The longitudinal etch depth for the light-emitting surface that the present embodiment obtains is 1 micron, lateral etches 0.7 micron of depth.Fig. 4 provides the scanning electron microscope (SEM) photograph after the light-emitting surface roughening treatment of the light emitting diode of the present embodiment.

The present embodiment has following technical effect：

In the present embodiment, it is more than or equal to 1 micron by longitudinal etch depth, guarantees that the roughness of light-emitting surface is high as far as possible In the case of, to improve light-out effect.If longitudinal etch depth is lower than 1 micron, roughness is reduced, and light-out effect improves unobvious. Through the depth of lateral etches between 0-0.8 microns, when transmitting light is projected from light-emitting surface, the light of side or surrounding under the electrodes Line projects after the diffraction phenomena of light can be more projected or occurred from surrounding them from surrounding them, to be not blocked, mentions High light extraction efficiency.If the depth of lateral etches is more than 0.8 micron, the semiconductor layer of the electrode and lower section is electrically connected face Product is small, and electrode is caused to be easily separated from.The electrode extension width is preferably between 3-20 microns, in conjunction with above-mentioned longitudinal etching The control of depth and lateral etches depth, electrode extension item will not be too thin, can further be effectively prevented from and electrode occur Be easily broken off caused by too thin, ESD reduced performance the technical issues of, to improve the service life of light emitting diode.

The above is only the preferred embodiment of the utility model, it is noted that for the technology people of the art Member, without departing from the principle of this utility model, can also make several improvements and modifications, these improvements and modifications are also answered It is considered as the protection scope of the utility model.

Claims (5)

1. a kind of light emitting diode, including the first semiconductor layer, luminescent layer, the second semiconductor layer, the second semiconductor layer side surface With light-emitting surface, electrode extension item positioned at light-emitting surface surface, below electrode extension item around light-emitting surface be etching formation Roughening treatment face, it is characterised in that：Electrode extension lower inner is formed along the light-emitting surface around below electrode extension item Lateral etches, lateral etches depth are more than or equal to 1 micron between 0-0.8um, longitudinal etch depth of light-emitting surface.

2. light emitting diode according to claim 1, it is characterised in that：Second semiconductor layer side connects with ohm Contact layer or current extending or Window layer, ohmic contact layer or current extending or Window layer are roughening treatment face.

3. light emitting diode according to claim 1 or 2, it is characterised in that：The electrode extension item include it is following it One metal：The combination of gold, platinum, copper, aluminium, titanium, nickel, germanium, chromium or the metal alloy or metal oxide.

4. light emitting diode according to claim 1 or 2, it is characterised in that：Go out light along surrounding below electrode extension item Face forms the depth of lateral etches between 0-0.3um, 0.3-0.5um or 0.5-0.8um.

5. light emitting diode according to claim 1 or 2, it is characterised in that：Electrode extension width is 3 ~ 20um.