TW591808B - Light-emitting diode with sapphire substrate - Google Patents

Abstract

The present invention is related to a kind of light-emitting diode (LED) with sapphire substrate. The invention is provided with a porous surface layer or the upper patterned structure for controlling the epitaxy growth procedure of GaN-based buffer layer to reduce strain. By using laser scanning, plasma etching or the predetermined mask to conduct chemical vapor etching, the porous surface layer or the upper patterned structure is formed.

Description

591808 __Case No. 89114878_ YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY etc. etc. The invention relates to a semiconductor device, especially a light emitting diode (LED) and a laser diode. According to the present invention, the present invention provides a light-emitting diode structure with an asymmetric protective layer comprising: a sapphire substrate having a thin porous surface layer or a porous structure with a top-like porous structure to control the growth of a four-element InAlGaN buffer layer Process (nucleation process), and reduce the resulting strain; a four-element InAlGaN buffer layer;

An n-type GaN layer, a tunnel barrier, and an electron spreading layer, located between the electron emission layer and the active layer, and formed of a group of three or five materials; an active layer made of a group of three or five materials, which generates one or more A potential energy well of electrons and holes, in which a radiative recombination of electrons and holes is produced; a hole emitting layer made of P-type AlGaN; a P-type contact layer made of P-type InGaN; and = Metal ohmic contact in contact with alpha helium / same emitting layer.

Take the thickness of the tunnel barrier and the electron spreading layer between 5 and 5 'and the width of the active layer between 5 angstroms and 0.1; the width of the sub-panel (from 5 angstroms to 1 #m) and the width between 5 〇Angle X f layer (for example, the width of the f-type contact layer is between 50 Angstroms and " hearts.,: Between '= layer (its width can be between 50 Angstroms and _), and η type = one The electron is widely formed and its generation-potential energy and electron accumulation layer of electrons. ——Five materials The LED device of the present invention can achieve the following objectives: a good hole injection in the # region.

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The active region has good crystal structure quality. High internal efficiency. Good light extraction. In order to achieve the purpose of the above description, the following individual parts are characteristic of the examples of the present invention, and are also the present invention: or, and, in a nutshell, the application of an asymmetric protective layer to avoid electrons from the active region buffer layer. + Generate a strained lattice to stop penetrating into the active region i and improve light extraction from the structure. ’, Sexual displacement,. A four-element alloy protective layer provides a lattice match between the protective layer and the active region. The crystals of the buffer layer grow through the internal strain. Structure, this structure encapsulates the GaN layer 3, one P-contact. It is based on GaN-a h N buffer layer 2; • low n-InGaN first-sheath layer 8; -up and a P-contact. The laterally confined active region avoids the carrier ’s non-regulated porous sapphire surface layer to control the four-element alloy process and reduces the epitaxial layer. 1, a GaN buffer layer 2, an η InGaN active layer 4, a P-type GaN layer 5, an η-contact and the second figure show a single quantum well LED with a symmetrical protective layer in the conventional technology, which includes A sapphire substrate; an n-GaN layer 3;-Fu Weier's second thin sheath layer β; a sheath layer 7; an active area 4; a p-AlGaN p-th first sheath 9; a p- GaN layer 5; — η-contact

In the present invention, an asymmetric protective layer is used to prevent electrons from leaking out of the active region, and the problem of low P-type mobility can be overcome. Add one to the second picture, and the p-GaN of Figure 1

591808 Case number 89114878 V. Description of the invention (3) One year month Correction Layer 5 is replaced by p-InGaN layer 1 1. An additional GaN current dispersing layer 12 is also added so that better lateral uniformity can be obtained when electrons are injected. In the fourth figure, an additional electron-emitting layer 3 is added to obtain better lateral uniformity of electron injection. In the fifth figure, an additional spiral displacement stop layer is provided, which is based on a superlattice structure or a strained superlattice provided by a decentralized Bragg reflector (this layer functions as a mirror). . In the sixth figure, a filter based on a metal layer or a metal dielectric is used. In the seventh figure, the composition of the four-element alloy compound in the sheath increase 16 and 17 is adjusted to achieve the purpose of lattice matching. The strain in the active layer 4 is suppressed. Use an additional hierarchical structure to create layers of hair 8 for the same purpose. j The eighth figure shows an improved structure in which the lateral confinement of carriers is used in the active region 4, which contains separate nGaN islands. This island structure is embedded in the confinement layer. 9 The ninth figure in the wide-gap matrix provided by, 29 shows the reverse pattern in the structure of FIG. 3. Applying this can apply a simpler method to prepare a transparent metal contact in front. ~, In the example described above, the growth on the surface of the buffer layer ((^, 11- 乂 11111 ^-GaN-based hurry = crystal, where (see the third figure) is widely distributed in the ζ body The role of 丨 η in semiconductors is to suppress the formation of crystals ^: This has excellent crystalline characteristics, but also has a fairly flat; nature: because. ^^ ± 511 u can increase the growth of crystals, Because = Bill U.lVMAWfliWlML !! itftti «, υιυι ··· ,,,„ —_ Dagger》 Xian V. Description of the invention (4) Deposition of a small buffer layer Φ ^

The GaN layer is very difficult: the time required: a P-type grows on the traditional buffer layer. For this reason, the wire μ is transmitted because the film has extremely poor crystalline characteristics. By way of example, n-type GaN is grown on a gemstone substrate of the present invention. According to the present invention, it can be directly on the buffering sound ^: species ^ type ㈣ ^ (see the ninth figure). The order grows up, and has the reverse LED configuration (see or it will explain the characteristics of the present invention, which contains the control of the respective characteristics: gLu1 pore surface layer or the structure of the pattern above to grow. This porous surface layer Or the above pattern II type Id paste is changed with a suitable photomask because P type

(3 0 0 -Vv .sec), M ^ l ^ / ^; ^ rj7lbn ^ GaN ΓΗ 丨 Two additional layers can prevent escape ... leaking out (see = penetrating into the superlattice of ΪΞίϊ strain to stop the occurrence of helical displacement And penetrates into the active region, and can improve the light extraction of the structure (7) (see Figure 5). In the present invention, a four-element alloy protective layer is used to provide lattice matching in the protective layer and the active layer (see Figure 7). Use laterally restricted active regions to prevent μ-binding (see Figure 8). This side; non-radiative active regions can use quantum structures 59808_Case No. 89114878 _ 年月 日 _ Amendment 5. The description of the invention (5) is formed, such as a quantum dot with a composition of (〇8 ^ 111) 7111111 ^.

Page 8 11 ·! 591808 _Case No. 89114878_Year Month Day_Revised Drawings Simple Explanation Drawing No. Description Gemstone Matrix 1 G a N Buffer Layer 2 η Type GaN Layer 3 1 n G a N Active Layer 4 P Type GaN layer 5 Low η-AlGaN second sheath layer 6 Low n-lnGaN first sheath layer 7 p-AlGaN first sheath layer 8 p-AlGaN second sheath 9 p- I nGaN layer 11 i- G a N current dispersion layer 12 additional electron emission layer 13 spiral displacement stop layer 14 external mirror 15 sheath layer 16 ^ 17 confinement layer 19 ^ 29

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Claims (1)

591808 Case No. 89114878 Amendment 6. Scope of patent application1. A light-emitting diode structure with an asymmetric protective layer includes: a supervised gemstone substrate with a thin porous surface layer or a porous structure with the above pattern to control a four-element InAlGaN Nucleat ion process of the buffer layer, and reduce the generated strain; η paste μ A four-element InAlGaN buffer layer; an n-type GaN layer; a penetrating barrier and an electron spreading layer, formed between the electron emission layer and the active layer, and formed of a group 35 material; an activity made of a group 35 material Layer, which produces one or more potential wells for electrons and holes, in which a radiative recombination of electrons and holes is created; a hole-emitting layer made of P-type AlGaN; a layer made of P-type InGaN A P-type contact layer; and a metal ohmic contact in contact with the hole emitting layer. 2. The structure of the first item of the patent application, wherein the thickness of the active layer is between 5 and 50 angstroms, and the width of the active layer is between 5 angstroms and 0 ·}. Between 50 angstroms and 1 and the width of the p-type contact 'layer is between 50 angstroms and 1 // m. 3. For the structure of the scope of the first patent application, a thunder emitting layer made of n-type or undoped III-V materials is added, and an electron accumulation layer capable of being used for these electrons is generated. I. The structure of the patent scope i) should be the structure of the hole surface layer or h pattern produced by laser scanning water etching and / or applying a photomask for chemical vapor etching. Μ 591808 _ Case No. 89114878_ Years and months Amendment _ 6. Scope of patent application 5. For the structure of the first scope of patent application, the structure is an asymmetric structure. 6. The structure of claim 1 in the scope of patent application, wherein a superlattice that generates strain is used to stop the helicity displacement through the active region, and to improve the light extraction of the structure. 7. The structure of item 1 of the scope of patent application, in which a laterally confined active area is used to reduce non-radiative binding of the carrier. Page 11