CN205376570U

CN205376570U - Adopt gaN base dual wavelength LED chip of flip -chip structure

Info

Publication number: CN205376570U
Application number: CN201620028317.0U
Authority: CN
Inventors: 李响
Original assignee: WUHU CEPREI INFORMATION INDUSTRY TECHNOLOGY RESEARCH INSTITUTE Co Ltd
Current assignee: WUHU CEPREI INFORMATION INDUSTRY TECHNOLOGY RESEARCH INSTITUTE Co Ltd
Priority date: 2016-01-08
Filing date: 2016-01-08
Publication date: 2016-07-06
Anticipated expiration: 2026-01-08

Abstract

The utility model discloses an adopt gaN base dual wavelength LED chip of flip -chip structure, include ceramic substrate and pass through the LED epitaxial wafer of soldering tin ceiling mounting on ceramic substrate, LED epitaxial wafer from last substrate, the gaN layer of not adulterateing, n type gaN layer, active layer and the p type gaN layer of including extremely down, the active layer includes first quantum well and second quantum well, and the luminous wavelength of first quantum well is 480nm~550nm, and the luminous wavelength of second quantum well is 420nm~480nm. The utility model discloses a LED chip adopts the flip -chip structure, and it makes conveniently, and the light outgoing is efficient, the light that the quantum well sent of two kinds of specific luminous wavelength is blue light and green glow respectively, arouses the ruddiness phosphor powder of specific kind to obtain ruddiness, and the three mixes the formation white light to reach good luminous effect.

Description

A kind of GaN base dual-wavelength LEDs chip adopting inverted structure

Technical field

This utility model relates to LED technology, is specifically related to a kind of GaN base dual-wavelength LEDs chip adopting inverted structure.

Background technology

III-nitride semiconductor material has the advantages such as energy gap big (0.7eV～6.2eV), the saturated migration rate height of carrier, breakdown electric field height, good heat conductivity, is very suitable for preparing the integrated-optic device of blue, green, ultraviolet light photo device and high frequency, high-power, anti-electromagnetic-radiation.

At present, the preparation method of commercial white light LEDs is to utilize metal-organic chemical vapor deposition equipment technology growth GaN base blue-ray LED epitaxial wafer, excites yttrium-aluminium-garnet yellow fluorescent powder to generate gold-tinted, and two parts light synthesizes white light further.This kind of white light LEDs has simple in construction, technical maturity, luminous efficiency advantages of higher.Shortcoming is to lack green glow and red color light component in light derived components, causes color rendering index relatively low (lower than 80), is applied in room lighting and aberration can be caused in backlight display field.

Another kind of Single chip white light LED solution is, adopts ultraviolet leds to excite red, green, blue fluorescent material to generate three primary colours, synthesizes white light further.The method can effectively solve color rendering index problem, but technique to realize difficulty higher.First, the preparation difficulty of current ultraviolet leds is higher；Secondly, the ratio of three kinds of fluorescent material need to strictly control, and encapsulation is difficulty with；Finally, ultraviolet light is harmful to for human body.

Additionally, also there is employing three-primary color LED to be encapsulated in a LEDs lamp bead, though color rendering index that can be real higher, the thing followed is Cost Problems.Except three kinds of LED chips of needs, also needing to configure more complicated drive circuit, practical significance is little.

For overcoming above difficulty, it is necessary to develop the White-light LED chip being easily achieved in a kind of high color rendering index (CRI), technique.

Utility model content

For this, this utility model provides that a kind of cost is low, be easily achieved in technique, the GaN base dual-wavelength LEDs chip adopting inverted structure that illumination effect is good.

This utility model be the technical scheme is that by its technical problem of solution

A kind of GaN base dual-wavelength LEDs chip adopting inverted structure, including ceramic substrate and by the reverse mounted LED on ceramic substrate of scolding tin, described LED includes substrate, layer of undoped gan, n-type GaN layer, active layer and p-type GaN layer from top to bottom, n-type GaN layer with p-type GaN layer is respectively equipped with the electrode contacted with scolding tin, described active layer includes the first SQW and the second SQW, the emission wavelength of the first SQW is 480nm～550nm, and the emission wavelength of the second SQW is 420nm～480nm.

As preferred embodiment, described electrode is be deposited with, in n-type GaN layer and p-type GaN layer, the high reflectance electrode obtained.

As preferred embodiment, it is the region formed in p-type GaN layer etching that described n-type GaN layer arranges the position of electrode.

As preferred embodiment, the first SQW and the second SQW are InGaN or AlInGaN.

As preferred embodiment, described substrate is Sapphire Substrate.

The beneficial effects of the utility model are: LED chip of the present utility model adopts inverted structure, and it is easy to make, and light outgoing efficiency is high；The light that the SQW of two kinds of specific emission wavelengths sends respectively blue light and green glow, excite particular kind of red light fluorescent powder to obtain HONGGUANG, and three is mixed to form white light, thus reaching good illumination effect；Especially, when electrode adopts high reflectance electrode, reverse the sent light of active layer can be turned back substrate side by reflection, thus improving light extraction efficiency further.

Accompanying drawing explanation

It is further detailed below in conjunction with the drawings and specific embodiments:

Fig. 1 is the structural representation of a kind of embodiment of this utility model.

Accompanying drawing illustrates: 1-ceramic substrate, 2-LED epitaxial wafer, 3-scolding tin, 4-substrate, 5-layer of undoped gan, 6-n type GaN layer, 7-active layer, 8-p type GaN layer, 9-electrode.

Detailed description of the invention

With reference to Fig. 1, a kind of GaN base dual-wavelength LEDs chip adopting inverted structure of the present utility model is mainly made up of ceramic substrate 1 and LED 2, and LED 2 is reverse mounted on ceramic substrate 1 by scolding tin 3, forms inverted structure.

LED 2 includes substrate 4, layer of undoped gan 5, n-type GaN layer 6, active layer 7 and p-type GaN layer 8 from top to bottom, and wherein substrate 4 adopts Sapphire Substrate.Being respectively equipped with electrode 9 in n-type GaN layer 6 and p-type GaN layer 8, n-type GaN layer 6 contacts with scolding tin 3 respectively through electrode 9 with p-type GaN layer 8, is connected with the power supply being located on ceramic substrate 1 thereby through scolding tin 3.

Active layer 7 is located between n-type GaN layer 6 and p-type GaN layer 8, and active layer 7 includes the first SQW and the second SQW, the first SQW and the second SQW and InGaN or AlInGaN can be adopted to realize.Wherein the emission wavelength of the first SQW is 480nm～550nm, and the emission wavelength of the second SQW is 420nm～480nm.The SQW adopting wavelengths above can so that active layer 7 sends blue light and green glow.During work, blue light and green glow that active layer 7 sends pass n-type GaN layer 6 and layer of undoped gan 5, from substrate 4 side outgoing.When LED chip is packaged, only need side a pair 420nm～500nm of configuration further on the substrate 4 to have a relatively strong light absorption, and the higher red light fluorescent powder of emission effciency can cooperatively form white light with blue light and green glow.By controlling the thickness of red light fluorescent powder encapsulating material, regulate and control relative intensity blue, between green glow and the HONGGUANG of phosphor emission reference standard Colour figure, the white light emission of high color rendering index (CRI) can be realized.

In order to improve light extraction efficiency further, the high reflectance electrode that the electrode being located in n-type GaN layer and p-type GaN layer obtains preferably by the mode being deposited with.The light that active layer can be sent by this electrode plays the effect of reflection, it is ensured that most of light that active layer sends can penetrate from substrate side.

Manufacturing process citing based on the LED chip of this utility model structure describes as follows.

1) adopt metal-organic chemical vapor deposition equipment technology, grow one layer of layer of undoped gan.Particularly as follows: using sapphire as substrate, adopt the high temperature of 1150 DEG C, high-temperature baking 5 minutes under an atmosphere of hydrogen, substrate carried out pretreatment.It is cooled to 550 DEG C, passes into ammonia, surfaces nitrided 5 minutes.Pass into trimethyl gallium (TMGa) and ammonia, grown buffer layer simultaneously.It is warming up to 1050 DEG C, grows 3 μ m-thick undoped p GaN epitaxial layer.

2) one layer of n-type GaN layer of growth.Particularly as follows: keep temperature-resistant, with the diluted silane (SiH of 200ppm₄) for n-type doped source, grow 500nmn type GaN layer.

3) the first quantum well structure of blue wave band is grown.Particularly as follows: at 850 DEG C, pass into triethyl-gallium (TEGa) and ammonia, grow GaN barrier layer.At 750 DEG C, pass into triethyl-gallium, ammonia and trimethyl indium (TMIn), grow InGaN well layer.

4) the second quantum well structure of green light band is grown.Particularly as follows: at 850 DEG C, pass into triethyl-gallium and ammonia, grow GaN barrier layer.At 720 DEG C, pass into triethyl-gallium, ammonia and trimethyl indium, grow InGaN well layer.

5) one layer of p-type GaN layer of growth.Particularly as follows: at 850 DEG C, with two luxuriant magnesium (Cp₂Mg) grow 200nmp type GaN for p-type doped source, and anneal 10 minutes at 700 DEG C.

6) high reflectance electrode is prepared.Particularly as follows: utilize inductively coupled plasma (ICP) method, go out n-type GaN layer in epitaxial wafer surface etch, and be deposited with high reflectance electrode in surface p-type GaN layer with the n-type GaN layer etched.

7) LED inversion is welded on ceramic substrate.

The foregoing is only preferred embodiment of the present utility model, be not limited to this utility model, for a person skilled in the art, this utility model can have various modifications and variations.All within spirit of the present utility model and principle, any amendment of making, equivalent replacement, improvement etc., should be included within protection domain of the present utility model.

Claims

1. the GaN base dual-wavelength LEDs chip adopting inverted structure, including ceramic substrate and by the reverse mounted LED on ceramic substrate of scolding tin, it is characterized in that: described LED includes substrate, layer of undoped gan, n-type GaN layer, active layer and p-type GaN layer from top to bottom, n-type GaN layer with p-type GaN layer is respectively equipped with the electrode contacted with scolding tin, described active layer includes the first SQW and the second SQW, the emission wavelength of the first SQW is 480nm～550nm, and the emission wavelength of the second SQW is 420nm～480nm.

2. a kind of GaN base dual-wavelength LEDs chip adopting inverted structure according to claim 1, it is characterised in that: described electrode is be deposited with, in n-type GaN layer and p-type GaN layer, the high reflectance electrode obtained.

3. a kind of GaN base dual-wavelength LEDs chip adopting inverted structure according to claim 1 and 2, it is characterised in that: it is the region formed in p-type GaN layer etching that described n-type GaN layer arranges the position of electrode.

4. a kind of GaN base dual-wavelength LEDs chip adopting inverted structure according to claim 1, it is characterised in that: the first SQW and the second SQW are InGaN or AlInGaN.

5. a kind of GaN base dual-wavelength LEDs chip adopting inverted structure according to claim 1, it is characterised in that: described substrate is Sapphire Substrate.