CN106876544A

CN106876544A - A kind of spontaneous White-light LED chip structure of GaN base unstressed configuration powder and preparation method thereof

Info

Publication number: CN106876544A
Application number: CN201710270077.4A
Authority: CN
Inventors: 杨国锋; 汪金; 张秀梅; 谢峰; 钱维莹
Original assignee: Jiangnan University
Current assignee: Jiangnan University
Priority date: 2017-04-24
Filing date: 2017-04-24
Publication date: 2017-06-20
Anticipated expiration: 2037-04-24
Also published as: CN106876544B

Abstract

The present invention relates to spontaneous White-light LED chip structure of a kind of GaN base unstressed configuration powder and preparation method thereof, wherein preparation method includes：GaN cushions, N-type GaN, silica membrane are sequentially depositing on a sapphire substrate.Using photoetching technique along Sapphire Substrate [1 100] and [11 20] crystal orientation in described SiO₂Performed etching on film, prepare SiO₂Mask.Grow N-type GaN, InGaN/GaN SQW, p-type GaN, transparency conducting layer successively in silicon dioxide mask layer and prepare N-type and P-type electrode.The present invention takes into account the current conventional semiconductor devices technological process of production, it is possible to achieve the ejecting white light under conditions of unstressed configuration powder, it is to avoid influence of the fluorescent material to the attenuation of white light LEDs.

Description

A kind of spontaneous White-light LED chip structure of GaN base unstressed configuration powder and preparation method thereof

Technical field：

The invention belongs to luminescent device manufacture field, and in particular to a kind of spontaneous White-light LED chip knot of GaN base unstressed configuration powder Structure and preparation method thereof.

Background technology：

Light emitting diode is described as the lighting source of a new generation, and outer illumination indoors, large-size screen monitors show, backlight, traffic signals The every field such as lamp, auto lamp all have a wide range of applications.

Realize that white-light illuminating is always the focus of research using semiconductor, at present conventional and the most ripe one kind side Method is one layer of yellow fluorescent powder of smearing on blue-light LED chip so that blue light and gold-tinted are mixed to form white light, but fluorescent material Material is very big to the influence of fading of white light LEDs.Another kind is to reach white light using ultraviolet leds plus the wavelength fluorescent powder of RGB tri- Effect, its luminous efficiency goes up well many than blue light, but the method still faces larger technical bottleneck, that is, how fluorescence Powder is effectively attached on crystal grain.

Therefore, prepare efficient White-light LED chip, be always those skilled in the art's technical problem urgently to be resolved hurrily it One.

The content of the invention：

It is an object of the invention to provide spontaneous White-light LED chip structure of a kind of GaN base unstressed configuration powder and preparation method thereof, The preparation of the structure LED chip is can be achieved with existing Process ba- sis, and can realize being sent out in the case of unstressed configuration powder Go out white light.

To solve the above problems, the invention provides a kind of spontaneous White-light LED chip structure of GaN base unstressed configuration powder and its system Preparation Method, comprises the following steps：

Sapphire material substrate is provided, [1-100] and [11-20] crystal orientation is marked；

In described Sapphire Substrate buffer layer, it is preferred that cushion is GaN film；

The deposited n-type GaN film on the GaN cushions；

SiO is deposited in the N-type GaN film₂Film, described SiO₂Film thickness is 150-300nm；

Along Sapphire Substrate [1-100] and [11-20] crystal orientation in described SiO₂Performed etching on film, obtain SiO₂Cover Film.Preferred SiO₂The width of mask is about 8nm, is spaced 4nm.

In described SiO₂N-type GaN, InGaN/GaN SQW, p-type GaN are sequentially depositing on mask；

It is etched to N-type GaN surfaces and forms the N-type electrode electrically connected with N-type GaN layer, the p-type that formation is electrically connected with p-type GaN Electrode；

Brief description of the drawings

Fig. 1-5 be GaN base White-light LED chip structure of the present invention the embodiment of preparation method one in the structure of each step show It is intended to.

Fig. 6 is the ESEM top view of GaN base white light LEDs epitaxial wafer in the embodiment of the present invention.

Fig. 7 is electroluminescence spectrum of the GaN base White-light LED chip under the driving current of 150mA in the embodiment of the present invention.

Specific embodiment

Below in conjunction with the drawings and specific embodiments to a kind of spontaneous white light LEDs core of GaN base unstressed configuration powder proposed by the present invention Chip architecture and preparation method thereof is further described.According to following explanation and claims, advantages and features of the invention To become apparent from.It should be noted that, accompanying drawing using very simplify in the form of and use non-accurately ratio, be only used to conveniently, Lucidly aid in illustrating the purpose of the embodiment of the present invention.

Referring first to Fig. 1, there is provided substrate 100, the backing material is sapphire (Al₂O₃) substrate.

Certain thickness cushion is deposited on the backing material, it is preferred that selected cushion is GaN film 101.

The deposited n-type GaN film 102 in described GaN film 101.

After this SiO is deposited in N-type GaN film 102₂Film 103, in embodiment, the SiO₂Film thickness 20nm。

Fig. 2, Fig. 3 are refer to, along Sapphire Substrate [1-100] and [11-20] crystal orientation in described SiO₂On film 103 Perform etching, obtain graphical SiO₂Mask 104.It should be noted that along this two crystal orientation etching SiO₂Film 103 is follow-up The GaN film that growth obtains different crystal structure provides critical effect.In example, described SiO₂The width of mask 104 Degree is about 8nm, is spaced 4nm.Using CF₄And O₂It is etching gas, standard photolithography process and reactive ion etching prepare graphical SiO₂Mask 104 is, it is necessary to explanation, the lithographic method and technique that this example is used are an example of the present invention, this hair It is bright to preparing the SiO₂The method of mask 104 is not construed as limiting.Fig. 2 is SiO₂The generalized section of mask 104, Fig. 3 is SiO₂Cover The schematic top plan view of film 104.

Fig. 4 is refer to, in the SiO₂N-type GaN film 105, InGaN/GaN SQWs are sequentially depositing on mask 104 106a and 106b, p-type GaN film 107.It should be noted that InGaN/GaN SQWs 106a and 106b are under identical conditions What growth was obtained.

Fig. 5 is refer to, transparency conducting layer 108 is deposited on described p-type GaN film surface；Etch epitaxial wafer to N-type GaN Surface forms the N-type electrode 109 electrically connected with N-type GaN layer, the P-type electrode 110 that formation is electrically connected with transparency conducting layer 108.

Specifically, in embodiment, the growth temperature of described GaN film cushion 101 is 500 DEG C.Described N-type The thickness of GaN film 102 is 2 μm, and growth temperature is 1010 DEG C.The growth temperature of described N-type GaN film 105 is 990 DEG C.Institute GaN potential barriers layer growth temperature in the InGaN/GaN SQWs 106 stated is 780 DEG C, and the growth temperature of InGaN is 670 DEG C.Institute The temperature of the p-type GaN film 107 stated is 950 DEG C.Fig. 6 is GaN base White-light LED chip ESEM (SEM) of preparation in experiment Top view.Fig. 7 is electroluminescence spectrum (EL) of the GaN base white light LED part of preparation in experiment under 150mA driving currents. It can be seen that quantum well radiation peak prepared by the present invention has two glow peaks of 445nm and 560nm.This is due in c In constituent contents are compared to the InGaN amounts grown on semi-polarity face (1-101) in the InGaN SQWs 106a of face (0001) growth Sub- trap 106b is high so that the SQW grown on same chip can send two kinds of light of wave band, the spectrum weight of this two wave band It is folded to cause that LED chip sends approximate white light, so as to realize the preparation of the GaN base white light LEDs of unstressed configuration powder.

Furthermore, it is necessary to explanation is, although as above, but the present invention is not limited to this to present disclosure.LED of the invention Chip structure can be, but not limited to be obtained using above-mentioned preparation method.Any those skilled in the art, are not departing from the present invention Spirit and scope in, can make various changes and modification, therefore protection scope of the present invention should be limited with claim Scope be defined.

Claims

1. spontaneous White-light LED chip structure of a kind of GaN base unstressed configuration powder and preparation method thereof, it is characterised in that including：

Sapphire Substrate is provided, in substrate face buffer layer, N-type GaN, SiO₂Film；

Along Sapphire Substrate [1-100] and [11-20] crystal orientation in described SiO₂Performed etching on film, obtain SiO₂Mask；

It is etched to N-type GaN surfaces and forms the N-type electrode electrically connected with N-type GaN layer, the p-type electricity that formation is electrically connected with p-type GaN Pole.

2. spontaneous White-light LED chip structure of a kind of GaN base unstressed configuration powder according to claim 1 and preparation method thereof, its It is characterised by：Performed etching along Sapphire Substrate [1-100] and [11-20] crystal orientation on described SiO2 films and to form groove and open Mouthful, it is easy to epitaxial lateral overgrowth GaN film.

3. spontaneous White-light LED chip structure of a kind of GaN base unstressed configuration powder according to claim 1 and preparation method thereof, its It is characterised by：Preferred orientation polar surface N-type GaN and [1-101] preferred orientation semi-polarity are grown on described SiO2 masks Face N-type GaN.

4. spontaneous White-light LED chip structure of a kind of GaN base unstressed configuration powder according to claim 1 and preparation method thereof, its It is characterised by：There are different In components in the InGaN/GaN SQWs of described N-type GaN superficial growths.

5. spontaneous White-light LED chip structure of a kind of GaN base unstressed configuration powder according to claim 1 and preparation method thereof, its It is characterised by：It is etched to N-type GaN surfaces and forms the N-type electrode electrically connected with N-type GaN layer, the P that formation is electrically connected with p-type GaN Type electrode.

6. spontaneous White-light LED chip structure of a kind of GaN base unstressed configuration powder according to claim 1 and preparation method thereof, its It is characterised by：Chip can be realized under the growth conditions similar with common LED, and fluorescent material outgoing approximate white light is not used.