CN207338421U - A kind of LED chip of new P-GaN membrane structures - Google Patents

Abstract

The utility model discloses a kind of LED chip of new P GaN films structure, including substrate, cushion, n-type semiconductor layer, Quantum Well and p-type semiconductor layer, cushion, n-type semiconductor layer, Quantum Well and p-type semiconductor layer are set gradually on the substrate, wherein p-type semiconductor layer includes the Ag metal films formed by Ag nano-particles.By adding Ag metal films in p-type semiconductor layer, horizontal outgrowth can be promoted, induced dislocations are buried in oblivion, so as to improve the quality of P GaN films, while can improve the light efficiency of LED.

Description

A kind of LED chip of new P-GaN membrane structures

Technical field

LED chip field is the utility model is related to, particularly a kind of LED chip of new P-GaN membrane structures.

Background technology

At present, the light emitting diode of GaN base LED is determined by the internal quantum efficiency and light extraction efficiency of light emitting diode. GaN base LED is mainly using sapphire as substrate, due to sapphire insulating properties, p-type electrode and the N-shaped electricity of LED chip Pole can only be designed and produced in the same epitaxial surface of chip.Conventional GaN base LED structure includes substrate, n-type semiconductor layer, more Quantum well active district, p-type semiconductor layer and transparency conducting layer.Meanwhile Ag nano-particles strengthen with local surface plasma Effect, Ag nano-particles are applied to p-type semiconductor layer can improve the quality of P-GaN films and the light efficiency of LED.

Utility model content

To solve the above problems, the purpose of this utility model is to provide a kind of LED chip of new P-GaN membrane structures, By varying the structure of P-GaN films, so as to improve the quality of P-GaN films and the light extraction efficiency of LED chip.

Technical solution is used by the invention for solving the technical problem：

A kind of LED chip of new P-GaN membrane structures, it is characterised in that：Including substrate, n-type semiconductor layer, Quantum Well And p-type semiconductor layer, n-type semiconductor layer, Quantum Well and p-type semiconductor layer are set gradually on the substrate；The p-type semiconductor Layer includes P-GaN layers of bottom, P-GaN layers of top layer and the Ag metal films formed by Ag nano-particles, and the Ag metal films are located at bottom Between P-GaN layers of top layer, described bottom P-GaN layers are arranged in Quantum Well P-GaN layers of layer.

Further, described bottom P-GaN layers are smooth layer structure or non-flat with the contact surface of Ag metal films Whole island structure.

Further, described top layer P-GaN layers and the opposing surface of the contact surface of Ag metal films are smooth layer structure.

Further, the n-type semiconductor layer is N-GaN layers, and the Quantum Well is InGaN/GaN Quantum Well.

Further, the substrate is made by sapphire material.

Further, cushion is further included, the cushion is arranged between substrate and n-type semiconductor layer.

Further, the cushion is made by AlGaN material.

The beneficial effects of the utility model are：A kind of LED core for new P-GaN membrane structures that the utility model uses Piece, including substrate, n-type semiconductor layer, Quantum Well and p-type semiconductor layer, the p-type semiconductor layer are included by Ag nano-particle shapes Into Ag metal films.Using Ag nano-particles as mask, horizontal outgrowth can be promoted, induced dislocations are buried in oblivion, so as to improve The quality of P-GaN films；Meanwhile Ag nano-particles have local surface plasma enhancement effect, it is possible to increase hole concentration, Defect luminescence can effectively be suppressed at the same time, so as to increase substantially the light efficiency of LED；In addition, Ag nano-particles to light have it is very high Emissivity, proposition efficiency of the P-GaN films to light can be increased substantially, so as to improve the light efficiency of LED.Ag nano-particles have Beneficial to the resistance for reducing P-GaN films, the injection efficiency in hole is improved；At the same time, additionally it is possible to reduce Mg acceptor activation energy.

Brief description of the drawings

The utility model is described in further detail with example below in conjunction with the accompanying drawings.

Fig. 1 is a kind of concrete structure diagram of the LED chip of new P-GaN membrane structures of the utility model.

Embodiment

With reference to Fig. 1, a kind of concrete structure diagram of the LED chip of new P-GaN membrane structures of the utility model, uses MOCVD technologies grow AlGaN cushions 20, N-GaN layers 30,40 and of InGaN/GaN Quantum Well successively in Sapphire Substrate 10 P-GaN layers, wherein P-GaN layers includes bottom P-GaN layers 51, top layer P-GaN layers 53 and the Ag gold formed by Ag nano-particles 52 Belong to film, the Ag metal films are located between bottom P-GaN layers 51 and top layer P-GaN layers 53, and the bottom P-GaN layers 51 are grown in In Quantum Well.P-GaN layers of thickness is generally 300-500nm.A kind of LED of the new P-GaN membrane structures of the utility model Chip can be applied to formal dress, upside-down mounting and vertical stratification.

Substrate is made using sapphire material, in general, GaN base material and epitaxial layer are mainly grown in Sapphire Substrate On 10.The production technology of Sapphire Substrate 10 is ripe, and device quality is preferable, and sapphire chemical stability is preferable, and light is inhaled Zoom in, can be used in higher temperature growth processes, in addition, sapphire high mechanical strength, is easily handled and cleans.

Due to GaN and 10 lattice mismatch of Sapphire Substrate, it is therefore desirable to growth of planar without the high-quality GaN of crackle outside Prolong that layer is extremely difficult, so as to being used as buffering two sections of growth methods with high growth temperature GaN again by the use of low-temperature epitaxy AlN or GaN It is flat such as mirror, low excess carrier concentration, the high-quality GaN epitaxial layer of high electron mobility to obtain surface.So pass through introducing AlGaN cushions 20, alleviate the stress of extension GaN material on substrate, improve crystal quality significantly, so as to improve luminous Efficiency.

P-GaN layers include the Ag metal films formed by Ag nano-particles 52., can using Ag nano-particles 52 as mask Promote horizontal outgrowth, induced dislocations are buried in oblivion, so as to improve the quality of P-GaN films；Meanwhile Ag nano-particles 52 have local Surface plasma enhancement effect, it is possible to increase hole concentration, while can effectively suppress defect luminescence, so as to increase substantially The light efficiency of LED；In addition, Ag nano-particles 52 have very high emissivity to light, P-GaN films can be increased substantially to light Efficiency is proposed, so as to improve the light efficiency of LED.Ag nano-particles 52 advantageously reduce the resistance of P-GaN films, improve the note in hole Enter efficiency；At the same time, additionally it is possible to reduce Mg acceptor activation energy.

The contact surface of the bottom P-GaN layers 51 and Ag metal films, i.e. A surfaces can be smooth layer structure or For non-smooth island structure.The opposing surface of the contact surface of the top layer P-GaN layers 53 and Ag metal films, i.e. B surface is flat Whole layer structure.

The smooth layer structure or non-smooth island structure are determined by growth pattern, wherein layer growth Pattern can cause to generate smooth layer structure, and island growth pattern can cause to generate non-smooth island structure.

After the gas phase atom that the island growth pattern refers to adsorb over the substrate surface condenses, crystalline substance can be initially formed Core, core can constantly adsorb gas phase atom and form island, and island absorption gas phase atom forms film.When the combination energy ratio between evaporation atom When combination between substrate atom and evaporation atom can be many by force, just easily there is island growth pattern.The island growth, i.e. shape Both horizontally and vertically grown at the same time into nuclear island, with growing up for isolated nucleation island, surface roughness gradually increases.

Layered growth pattern refers to that elder generation equably covers one layer in substrate surface in the form of monoatomic layer, Ran Hou Three-dimensional grows first layer, the second layer and higher successively.When the combination between substrate atom and evaporation atom can be close to During combination energy between evaporation atom, just easily there is layer by layer growth mode.

When preparing the LED chip of the utility model, AlGaN cushions 20 are grown first in Sapphire Substrate 10, so N-GaN layers 30 are grown on AlGaN cushions 20 afterwards, InGaN/GaN Quantum Well 40 are then grown on N-GaN layers 30, then Bottom P-GaN layers 51 are grown in InGaN/GaN Quantum Well 40 again, growth pattern is two-dimensional layer growth, three-dimensional island growth Or two-dimensional layer growth and three-dimensional island growth are combined pattern, the difference of the growth pattern used can cause bottom P-GaN Smooth layer structure or non-smooth island structure is presented in the shape and structure on the A surfaces of layer 51.When having grown bottom P-GaN After layer 51, Ag metal materials then are being coated with bottom P-GaN layers 51, then quick high-temp is annealed, annealing time 30- 120 seconds, so that the Ag metal materials form the Ag metal films being made of Ag nano-particles 52 on bottom P-GaN layers 51, After Ag metal films are formed, reuse MOCVD technologies and top layer P-GaN layers 53 are grown on Ag metal films, in top layer P-GaN layers of growth 53 preceding middle phase growth pattern can be two-dimensional layer growth, three-dimensional island growth or two-dimensional layer growth and three-dimensional Island growth is combined pattern, using two-dimensional layer growth pattern is grown the B surface of top layer P-GaN layers 53 during final stage flat Whole, last reselection formal dress, upside-down mounting or vertical stratification are packaged.

The MOCVD technologies are a kind of new vapor phase epitaxial growth skills to grow up on the basis of vapor phase epitaxial growth Art.

Contrast three-dimensional island growth pattern and two-dimensional layer growth pattern, the speed of growth of the three-dimensional island growth pattern Comparatively fast, but caused dislocation can be more apparent；And the speed of growth of two-dimensional layer growth pattern is slower, but caused dislocation can be compared with It is few, therefore, in order to make LED chip grow more smooth, preferably select two-dimensional layer growth pattern.

The preferred embodiment of the above, simply the utility model, the utility model are not limited to above-mentioned implementation Mode, as long as it reaches the technique effect of the utility model with identical means, should all belong to the scope of protection of the utility model.

Claims (7)

1. A kind of 1. LED chip of new P-GaN membrane structures, it is characterised in that：Including substrate, n-type semiconductor layer, Quantum Well and P-type semiconductor layer, sets gradually n-type semiconductor layer, Quantum Well and p-type semiconductor layer on the substrate；The p-type semiconductor layer Including P-GaN layers of bottom, P-GaN layers of top layer and the Ag metal films formed by Ag nano-particles, the Ag metal films are located at bottom Between P-GaN layers and P-GaN layers of top layer, described bottom P-GaN layers are arranged in Quantum Well.
2. A kind of 2. LED chip of new P-GaN membrane structures according to claim 1, it is characterised in that：The bottom P- GaN layer is smooth layer structure or non-smooth island structure with the contact surface of Ag metal films.
3. A kind of 3. LED chip of new P-GaN membrane structures according to claim 1, it is characterised in that：The top layer P- The opposing surface of the contact surface of GaN layer and Ag metal films is smooth layer structure.
4. A kind of 4. LED chip of new P-GaN membrane structures according to claim 1, it is characterised in that：The N-shaped half Conductor layer is N-GaN layers, and the Quantum Well is InGaN/GaN Quantum Well.
5. A kind of 5. LED chip of new P-GaN membrane structures according to claim 1, it is characterised in that：The substrate by Sapphire material is made.
6. A kind of 6. LED chip of new P-GaN membrane structures according to claim 1, it is characterised in that：Further include buffering Layer, the cushion are arranged between substrate and n-type semiconductor layer.
7. A kind of 7. LED chip of new P-GaN membrane structures according to claim 6, it is characterised in that：The cushion It is made by AlGaN material.