CN202259400U

CN202259400U - White light emitting diode (LED) epitaxial structure and white LED chip structure

Info

Publication number: CN202259400U
Application number: CN2011204208138U
Authority: CN
Inventors: 李玉芝; 吉爱华; 祝菡菡
Original assignee: Weifang Guangsheng New Energy Co Ltd
Current assignee: Weifang Guangsheng New Energy Co Ltd
Priority date: 2011-10-29
Filing date: 2011-10-29
Publication date: 2012-05-30
Anticipated expiration: 2021-10-29

Abstract

The utility model discloses a white light emitting diode (LED) epitaxial structure and a white LED chip structure containing the epitaxial structure. The epitaxial sheet of the epitaxial structure comprises a ZnS substrate, a GaN transition layer, a first N-GaN contact layer, a Si and Zn-doped In0.2Ga0.8N/GaN multi-quantum well luminous layer, a first P-GaN contact layer, a N-GaN cascade layer, a second N-GaN contact layer, a Si and Zn-doped In0.49Ga0.51N/GaN multi-quantum well luminous layer and a second P-GaN contact layer which are sequentially arranged from bottom to top. Coating fluorescent powder is not used in the white LED epitaxial structure and the chip structure, so constraint of the fluorescent powder is radically eliminated; the utility model has good luminous quality and good color rendering property; the working stability is improved, the service life is prolonged, the encapsulation procedures are reduced, and the production process of the whole industrial chain of extension, chips, encapsulation and application of a white LED can be simplified; and the utility model has high production efficiency and is suitable for large-batch production.

Description

A kind of white light LEDs epitaxial structure, White-light LED chip structure

Technical field

The utility model relates to technical field of semiconductor illumination, specifically, and the White-light LED chip structure that relates to a kind of epitaxial structure of white light LEDs and include this epitaxial structure.

Background technology

White light LEDs have energy-saving and environmental protection, life-span long, can be operated in plurality of advantages such as fast state, its purposes is more and more wider, government just widelys popularize.At present; Usually adopt blue-ray LED to excite nontransparent yellow fluorescent powder to make white light LEDs through wavelength Conversion; Because continuing to light, blue-ray LED can cause temperature to raise; Material for transformation of wave length can be degenerated, and the light that blue chip sends phenomenons such as scattering absorption can take place during through yellow fluorescent powder, makes light extraction efficiency not high; Simultaneously because yellow fluorescent powder coating thickness inhomogeneous also can bring problems such as yellow aperture, blue hot spot, white light colour temperature be inconsistent, make poor, the poor stability of white light LEDs color rendering that excites yellow fluorescent powder to produce with blue-ray LED thus.

The color developing that how to improve existing white light LEDs is just becoming the current problem that everybody is concerned about the most with stability.

The utility model content

The utility model technical problem to be solved is: to above-mentioned present situation provide that a kind of color rendering is good, the white light LEDs epitaxial structure of good stability and the White-light LED chip structure that includes this epitaxial structure.

For solving above-mentioned technical problem about the white light LEDs epitaxial structure; The technical scheme of the utility model is: a kind of white light LEDs epitaxial structure; Comprise epitaxial wafer, said epitaxial wafer comprises the In of the ZnS substrate, GaN transition zone, a N-GaN contact layer, doping Si and the Zn that set gradually from bottom to up _0.2Ga _0.8The In of N/GaN multiple quantum well light emitting layer, a P-GaN contact layer, N-GaN cascade layer, the 2nd N-GaN contact layer, doping Si and Zn _0.49Ga _0.51N/GaN multiple quantum well light emitting layer and the 2nd P-GaN contact layer.

As preferably, the thickness of said ZnS substrate is 50～200um.

As preferably, the thickness of said GaN transition zone is 10～100 nm.

As preferably, the thickness of a said N-GaN contact layer, the 2nd N-GaN contact layer is 200～1000 nm.

As preferably, the In of said doping Si and Zn _0.2Ga _0.8The thickness of N/GaN multiple quantum well light emitting layer is 1000～10000nm.

As preferably, the thickness of a said P-GaN contact layer, the 2nd P-GaN contact layer is 80～600nm.

As preferably, the thickness of said N-GaN cascade layer is 100～1000 nm.

As preferably, the In of said doping Si and Zn _0.49Ga _0.51The thickness of N/GaN multiple quantum well light emitting layer is 1000～10000nm.

For solving above-mentioned technical problem about the White-light LED chip structure, the technical scheme of the utility model is: a kind of White-light LED chip structure comprises above-described epitaxial wafer; The 2nd P-GaN contact layer of said epitaxial wafer is provided with the P electrode, and a N-GaN contact layer is provided with the N electrode.

Owing to adopted technique scheme, the beneficial effect of the utility model is: because the white light LEDs epitaxial structure of the utility model is mix the simultaneously In of Si and Zn of growth respectively on same ZnS substrate _0.2Ga _0.8N/GaN multiple quantum well light emitting layer and In _0.49Ga _0.51N/GaN multiple quantum well light emitting layer obtains white light.Between 500～560nm, can obtain the donor-acceptor pair of broad band wavelength, the relevant broadband radiation of donor-acceptor pair can take place with Zn in Si, and the band edge radiation takes place in InGaN MQW LED, the two combination will produce white light.The In of this doping Si and Zn _xGa _{1-

x}The spectrum of the white light LEDs that the electroluminescent spectrum of N-GaN MQW LED and fluorescent material are converted to is closely similar.Through measuring, its colour temperature is 6300K, and chromaticity coordinates is (0.316,0.312).Because the white light LEDs epitaxial structure of the utility model and the White-light LED chip structure that includes this epitaxial structure need not apply fluorescent material; Therefore fundamentally broken away from the constraint of fluorescent material, its luminous mass is good, color rendering is good, good stability, has improved job stability and useful life; Reduced packaging process; The production technology of extension from white light LEDs, chip, encapsulation, application whole industry chain is simplified, and production efficiency is high, is suitable for producing in enormous quantities.

ZnS is nanometer materials, and band gap is wide, and refractive index is high, light transmittance is high, adopts ZnS to have good fluorescent effect and electroluminescence function as substrate.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further specified:

Fig. 1 is the epitaxial structure sketch map among the utility model embodiment;

Fig. 2 is the chip structure sketch map among the utility model embodiment;

Among the figure: the 1-ZnS substrate; 2-GaN transition zone; 3-the one N-GaN contact layer; The In of 4-doping Si and Zn _0.2Ga _0.8N/GaN multiple quantum well light emitting layer; 5-the one P-GaN contact layer; 6-N-GaN cascade layer; 7-the 2nd N-GaN contact layer; The In of 8-doping Si and Zn _0.49Ga _0.51N/GaN multiple quantum well light emitting layer; 9-the 2nd P-GaN contact layer; The 10-P electrode; The 11-N electrode.

Embodiment

As shown in Figure 1, a kind of white light LEDs epitaxial structure comprises epitaxial wafer, and said epitaxial wafer comprises the In of the ZnS substrate 1 that sets gradually from bottom to up, GaN transition zone 2, a N-GaN contact layer 3, doping Si and Zn _0.2Ga _0.8The In of N/GaN multiple quantum well light emitting layer 4, a P-GaN contact layer 5, N-GaN cascade layer 6, the 2nd N-GaN contact layer 7, doping Si and Zn _0.49Ga _0.51N/GaN multiple quantum well light emitting layer 8 and the 2nd P-GaN contact layer 9.The ZnS substrate is nanometer materials, and band gap is wide, and refractive index is high, light transmittance is high, has good fluorescent effect and electroluminescence function.

Wherein, the thickness of said ZnS substrate 1 is 50～200um, is preferably 100 um.

Wherein, the thickness of said GaN transition zone 2 is 10～100 nm, is preferably 50 nm.

Wherein, the thickness of a said N-GaN contact layer 3, the 2nd N-GaN contact layer 7 is 200～1000 nm, is preferably 500 nm.

Wherein, the In of said doping Si and Zn _0.2Ga _0.8The thickness of N/GaN multiple quantum well light emitting layer 4 is 1000～10000nm, is preferably 2000 nm.

Wherein, the thickness of a said P-GaN contact layer 5, the 2nd P-GaN contact layer 9 is 80～600nm, is preferably 250 nm.

Wherein, the thickness of said N-GaN cascade layer 6 is 100～1000 nm, is preferably 200nm.

Wherein, the In of said doping Si and Zn _0.49Ga _0.51The thickness of N/GaN multiple quantum well light emitting layer 8 is 1000～10000nm, is preferably 2000nm.

The manufacture method of the white light LEDs epitaxial structure of the utility model comprises growing epitaxial sheet step, and said growing epitaxial sheet step is following:

(a) selecting thickness is 50～200um; Be preferably the ZnS substrate 1 of 100 um; Clean up, ZnS substrate 1 is placed on sends into K465i MOCVD epitaxial furnace in the pallet, at 605～615 ℃ of following growing GaN transition zones 2; Until grown in thickness to 10～100 nm of said GaN transition zone 2, best when thickness is 50 nm.

(b) in said epitaxial furnace,,, best when thickness is 500 nm until grown in thickness to 200～1000 nm of a said N-GaN contact layer 3 at 1055～1065 ℃ of growth the one N-GaN contact layers 3.

(c) in said epitaxial furnace, pour nitrogen protection, at 685～695 ℃, the In of best 680 ℃ of grow doping Si and Zn _0.2Ga _0.8N/GaN multiple quantum well light emitting layer 4 is until the In of said doping Si and Zn _0.2Ga _0.8Grown in thickness to the 1000～10000nm of N/GaN multiple quantum well light emitting layer 4, best when thickness is 2000 nm.Press mass ratio, the doping of Si and Zn accounts for 0.15%～0.25% of this luminescent layer.

(d) in said epitaxial furnace, at 995～1005 ℃, best 1000 ℃ of growth the one P-GaN contact layers 5 are until grown in thickness to the 80～600nm of a said P-GaN contact layer 5; It is best when thickness is 250 nm.

(e) in said epitaxial furnace, at 905～1005 ℃, best 950 ℃ of growth N-GaN cascade layers 6, until grown in thickness to 100～1000 nm of said N-GaN cascade layer 6, best when thickness is 200nm.

(f) in said epitaxial furnace, protect with nitrogen, at 685～695 ℃, the In of best 690 ℃ of grow doping Si and Zn _0.49Ga _0.51N/GaN multiple quantum well light emitting layer 8 is until the In of said doping Si and Zn _0.49Ga _0.51Grown in thickness to the 1000～10000nm of N/GaN multiple quantum well light emitting layer 8, best when thickness is 2000 nm.Press mass ratio, the doping of Si and Zn accounts for 0.15%～0.25% of this luminescent layer.

(g) in said epitaxial furnace, at 995～1005 ℃, best 1000 ℃ of growth the 2nd P-GaN contact layers 9 grow to 80～600nm until said the 2nd P-GaN contact layer 9, and are best when thickness is 250 nm.Finally promptly make epitaxial wafer shown in Figure 1.

As shown in Figure 2, a kind of White-light LED chip structure comprises epitaxial wafer shown in Figure 1; The 2nd P-GaN contact layer 9 of said epitaxial wafer is provided with P electrode 10, the one N-GaN contact layers 3 and is provided with N electrode 11.

After producing epitaxial wafer shown in Figure 1; According to the core manufacturing blade technolgy flow process of following routine, can produce White-light LED chip structure shown in Figure 2: epitaxial wafer → cleaning → plating transparent electrode layer → transparency electrode figure photoetching → corrode → remove photoresist → platform graphics photoetching → dry etching → remove photoresist → anneal → SiO2 deposition → graph window photoetching → SiO2 corrodes → removes photoresist → N utmost point figure photoetching → prerinse → plated film → peel off → anneal → P utmost point figure photoetching → plated film → peel off → grind → cut → chip → finished product test.Wherein, when making electrode, P electrode 10 titanizing again of aluminizing earlier, N electrode 11 is vapor deposition titanium, aluminium, titanium, gold successively, so that combine better with the material of epitaxial structure.

The white light LEDs epitaxial structure of the utility model is mix the simultaneously In of Si and Zn of growth respectively on same ZnS substrate _0.2Ga _0.8N/GaN multiple quantum well light emitting layer and In _0.49Ga _0.51N/GaN multiple quantum well light emitting layer obtains white light, the In of this doping Si and Zn _xGa _{1-

x}N-GaN MQW LED structure also can adopt the method for MOVPE to grow.Between 500～560nm, can obtain the donor-acceptor pair of broad band wavelength, the relevant broadband radiation of donor-acceptor pair can take place with Zn in Si, and the band edge radiation takes place in InGaN MQW LED, the two combination will produce white light.The In of this doping Si and Zn _xGa _{1-

x}The spectrum of the white light LEDs that the electroluminescent spectrum of N-GaN MQW LED and fluorescent material are converted to is closely similar.Through measuring, its colour temperature is 6300K, and chromaticity coordinates is (0.316,0.312).Because the white light LEDs epitaxial structure of the utility model and the White-light LED chip structure that includes this epitaxial structure need not apply fluorescent material; Therefore fundamentally broken away from the constraint of fluorescent material, its luminous mass is good, color rendering is good, good stability, has improved job stability and useful life; Reduced packaging process; The production technology of extension from white light LEDs, chip, encapsulation, application whole industry chain is simplified, and production efficiency is high, is suitable for producing in enormous quantities.

The above is giving an example of the utility model preferred forms, and the part of wherein not addressing in detail is those of ordinary skills' common practise.The protection range of the utility model is as the criterion with the content of claim, and any teachings and equivalent transformation of carrying out based on the utility model is also within the protection range of the utility model.

Claims

1. a white light LEDs epitaxial structure comprises epitaxial wafer, it is characterized in that: said epitaxial wafer comprises the In of the ZnS substrate, GaN transition zone, a N-GaN contact layer, doping Si and the Zn that set gradually from bottom to up _0.2Ga _0.8The In of N/GaN multiple quantum well light emitting layer, a P-GaN contact layer, N-GaN cascade layer, the 2nd N-GaN contact layer, doping Si and Zn _0.49Ga _0.51N/GaN multiple quantum well light emitting layer and the 2nd P-GaN contact layer.

2. a kind of white light LEDs epitaxial structure as claimed in claim 1 is characterized in that: the thickness of said ZnS substrate is 50～200um.

3. a kind of white light LEDs epitaxial structure as claimed in claim 1 is characterized in that: the thickness of said GaN transition zone is 10～100 nm.

4. a kind of white light LEDs epitaxial structure as claimed in claim 1 is characterized in that: the thickness of a said N-GaN contact layer, the 2nd N-GaN contact layer is 200～1000 nm.

5. a kind of white light LEDs epitaxial structure as claimed in claim 1 is characterized in that: the In of said doping Si and Zn _0.2Ga _0.8The thickness of N/GaN multiple quantum well light emitting layer is 1000～10000nm.

6. a kind of white light LEDs epitaxial structure as claimed in claim 1 is characterized in that: the thickness of a said P-GaN contact layer, the 2nd P-GaN contact layer is 80～600nm.

7. a kind of white light LEDs epitaxial structure as claimed in claim 1 is characterized in that: the thickness of said N-GaN cascade layer is 100～1000 nm.

8. a kind of white light LEDs epitaxial structure as claimed in claim 1 is characterized in that: the In of said doping Si and Zn _0.49Ga _0.51The thickness of N/GaN multiple quantum well light emitting layer is 1000～10000nm.

9. a White-light LED chip structure is characterized in that: comprise each described epitaxial wafer in the claim 1 to 8; The 2nd P-GaN contact layer of said epitaxial wafer is provided with the P electrode, and the N-GaN contact layer is provided with the N electrode.