CN101174668A - Semiconductor light emitting element and method for manufacturing the same - Google Patents

Abstract

The invention discloses a semiconductor light-emitting component and a manufacturing method thereof, the semiconductor light-emitting component is provided with an opaque substrate, a combination structure formed on the opaque substrate, a semiconductor light-emitting laminated layer formed on the combination structure, and a fluorescent material structure formed on the semiconductor light-emitting laminated layer, and the semiconductor light-emitting laminated layer is separated from an original growth substrate. The method for manufacturing the semiconductor light-emitting element comprises the steps of separating a semiconductor light-emitting laminated layer from an original growth substrate, combining the semiconductor light-emitting laminated layer on an opaque substrate, and forming a fluorescent material structure above the semiconductor light-emitting laminated layer.

Description

Semiconductor light emitting element and manufacturing method thereof

This application is a divisional application of Chinese Patent Application No. 200410077053.X with a filing date of September 10, 2004 and an invention title of "Semiconductor Light-Emitting Element and Manufacturing Method Thereof".

technical field

The invention relates to a semiconductor light-emitting element, in particular to a semiconductor light-emitting element with a fluorescent material structure.

Background technique

Semiconductor light-emitting elements, such as: Light Emitting Diode (Light Emitting Diode), Organic Light Emitting Diode (Organic Light Emitting Diode) and Laser Diode (Laser Diode), etc., have small size, good luminous efficiency, long life, fast response and high reliability. And the advantages of good monochromaticity have been widely used in various electronic devices, automobile industry, advertising billboards and traffic display signs. And there is a tendency to gradually replace traditional lighting sources.

Traditionally, in order to form white light, a combination of blue light-emitting diode crystal grains and fluorescent materials (such as: phosphor powder, etc.) is often used. The fluorescent material is excited by blue light to produce yellow light or green light and red light, and then blue light, yellow light Or green and red light mixed to form white light. Today's white light-emitting diodes generally use sapphire (Al ₂ O ₃ ), SiC or other transparent substrates as the substrate. Since the light will be emitted from the transparent substrate, in order to make all the light pass through the fluorescent material (such as phosphor powder) To form the required color, the fluorescent material must be cut into chips after the light-emitting diode wafer (Wafer) is cut (Dicing), and then covered on the entire light-emitting diode chip during the packaging process to avoid The light that is not converted by the fluorescent material is emitted through the transparent substrate to affect the color of the light emitted by the overall LED.

In addition, when the substrate is transparent, the fluorescent material needs to cover the transparent substrate or the LED crystal grains in addition to the top of the transparent substrate or the LED crystal grains. However, the fluorescent material should be evenly covered on the transparent substrate or the It is not easy to surround the LED crystal grains, which often causes uneven thickness distribution of the fluorescent material above and around the transparent substrate or LED crystal grains. When the light generated by the LED passes through the fluorescent material with uneven thickness, the thickness is thicker. More light will be absorbed at the thinner part, and less light will be absorbed at the thinner part, and the color of the light converted by the fluorescent material with different thickness will be different, so the light generated by the LED will be different in different directions. color. As disclosed in U.S. Patent No. 6,642,652, it is a flip-chip (Flip-Chip) semiconductor light-emitting element with a fluorescent material structure. In order to make the fluorescent material evenly cover the top and surroundings of the semiconductor light-emitting element, a complicated method is used. Manufacturing methods, such as electrophoresis, etc., however, often result in increased manufacturing costs and reduced yields due to complex manufacturing methods, which cannot effectively and simply solve the problem of uneven thickness of fluorescent materials.

In view of the above problems, the present invention proposes a semiconductor light-emitting element and its manufacturing method, which can form a fluorescent material layer on the wafer before die packaging, and can avoid light emission from the transparent substrate and uneven coverage due to the fluorescent material resulting color differences.

Contents of the invention

The semiconductor light-emitting element of the present invention includes an opaque substrate; a bonding structure; at least one semiconductor light-emitting laminate is combined with the opaque substrate through the bonding structure, and can emit an original light, and the semiconductor light-emitting laminate is separated from An original growth substrate; and a fluorescent material structure disposed above the semiconductor light-emitting stack and substantially conforming to the shape of the semiconductor light-emitting stack, and the fluorescent material structure includes a fluorescent material that can absorb the original light and generate a converted light .

The bonding structure in the semiconductor light-emitting element of the present invention includes a first intermediary layer, an adhesive layer and/or a second intermediary layer, and the above-mentioned structure can improve the bonding force between the semiconductor light-emitting stack and the opaque substrate, or An electrical connection is formed between the semiconductor light emitting stack and the light-proof substrate.

The fluorescent material structure of the present invention includes a fluorescent material, which can be directly formed on the semiconductor light-emitting stack, or formed on the semiconductor light-emitting stack by using an adhesive, and this fluorescent material can absorb light emitted from the semiconductor light-emitting stack. The resulting original ray is converted into a converted ray.

The manufacturing method of the semiconductor light-emitting element of the present invention includes separating a semiconductor light-emitting stack from an original growth substrate; combining the semiconductor light-emitting stack on an opaque substrate; and forming a fluorescent material structure above the semiconductor light-emitting stack.

Description of drawings

Figures 1a-1c are schematic structural views showing a semiconductor light-emitting element according to a preferred embodiment of the present invention; and

2a and 2b are schematic diagrams showing the structure of a semiconductor device according to another preferred embodiment of the present invention.

simple notation

10～semiconductor light emitting element; 11～opaque substrate; 12～bonding structure; 1201～first intermediary layer; 1202～bonding layer; 1203～second intermediary layer; 13～semiconductor light emitting stack; 1301～electric contact; 1302～groove; 14～fluorescent material structure; 1401～fluorescent material; 15～protective structure; 1501～optical layer; 1502～optical layer; and 16～reflective layer.

Detailed ways

In order to make your examining committee members better understand the characteristics of the present invention, several preferred embodiments are listed below, which are described in detail as follows in conjunction with the drawings:

first embodiment

1a-1c are schematic diagrams showing the structure of a semiconductor light emitting element in a preferred embodiment of the present invention. The semiconductor light emitting device 10 disclosed in the present invention includes: an opaque substrate 11 , a bonding structure 12 , a semiconductor light emitting stack 13 and a fluorescent material structure 14 . Among them, the semiconductor light-emitting stack 13 can generate original light, and because the original light does not penetrate the opaque substrate 11, most of the light-emitting regions of the semiconductor light-emitting element 10 are concentrated on the opposite side of the opaque substrate 11, that is, the semiconductor light-emitting element 10 is formed with a side of a fluorescent material structure 14 . When the original light enters the fluorescent material structure 14, the fluorescent material 1401 in the fluorescent material structure 14 will absorb the original light and generate converted light. Preferably, the original light and the converted light can be mixed to generate white light. In addition, the semiconductor light emitting stack 13 of the present invention can be a vertical structure (electrical contacts are located on different sides) or a horizontal structure (electrical contacts are located on the same side).

The material of the opaque substrate 11 can be a semiconductor substrate, a metal substrate, a combination of the above materials or other opaque materials, preferably, the material of the opaque substrate 11 can be Si, GaN/Si, GaAs or a combination thereof, in addition 1b, the opaque substrate 11 can be a wafer (Wafer), and grooves 1302 can be formed on the wafer 11 to separate more than two semiconductor light emitting stacks 13, preferably, the semiconductor light emitting stacks 13 The step of chip dicing can be performed after the fluorescent material structure 14 is formed.

As shown in FIG. 1 c , the opaque substrate 11 may also include a transparent substrate 1101 and a reflective layer 16 . Using the reflective layer 16 to reflect the light directed towards the transparent substrate 1101 allows the original light or/and the converted light to travel toward the direction of the fluorescent material 14 , and prevents the original light and/or the converted light from being emitted from the transparent substrate 1101 . Wherein, the material of the transparent substrate 1101 may be GaP, SiC, ZnO, GaAsP, AlGaAs, Al ₂ O ₃ , glass, a combination of the above materials or other alternative materials.

The bonding structure 12 is used for bonding the opaque substrate 11 and the semiconductor light emitting stack 13 . The bonding structure 12 can be a metal, so that the metal can be bonded with the opaque substrate 11 and the semiconductor light-emitting stack 13 at an appropriate temperature, and the physical properties of the metal can be used to form a mirror to reflect the light directed to the opaque substrate , or form an ohmic contact layer between the opaque substrate 11 and the semiconductor light emitting stack 13 to make the electrical connection between the opaque substrate 11 and the semiconductor light emitting stack 13 .

In addition, the bonding structure 12 can also be formed by directly bonding the opaque substrate 11 and the semiconductor light-emitting stack 13, using a relatively high temperature, such as 1000° C., and applying appropriate pressure to make the opaque substrate 11 and the semiconductor light-emitting stack The contact surface of 13 produces bond and combines.

Preferably, the bonding structure 12 combines the opaque substrate 11 and the semiconductor light-emitting stack 13 by gluing. This method can be carried out at a relatively low temperature to reduce the probability of damage to the semiconductor light-emitting stack 13 at high temperatures, and can achieve a suitable bonding effect. The material of the bonding structure 12 can be polyimide (PI), benzocyclobutene (BCB), perfluorocyclobutene (PFCB) or other organic bonding materials. In addition, the material of the bonding structure 12 can be transparent, for example, the above-mentioned benzocyclobutene (BCB). All outgoing light is directed in the same direction.

When the opaque substrate 11 and the semiconductor light-emitting stack 13 can be electrically connected, the semiconductor light-emitting stack 13 can form an electrical path in the vertical direction to become a semiconductor light-emitting element 10 with a vertical structure. At this time, the semiconductor light-emitting element One electrical contact 1301 of 10 can be arranged in the vertical direction, and the opaque substrate 11 itself becomes another electrical contact, or another electrical contact is formed on the opaque substrate 11 .

The fluorescent material structure 14 may include one or more fluorescent materials 1401, and the fluorescent material 1401 can absorb the original light generated from the semiconductor light-emitting stack 13 and generate converted light. The converted light generally refers to something different from the original light. Instead of only specifying one kind of light, two or more kinds of fluorescent materials 1401 can also be used to produce a variety of converted light. Moreover, in the present invention, the fluorescent material structure 14 is formed on the semiconductor light-emitting element 10 and generally conforms to the semiconductor The shape of the light emitting stack 13, therefore, can simplify the subsequent packaging process. Wherein, the fluorescent material 1401 can be fixed on the semiconductor light-emitting stack 13 by using an adhesive (Binder; not shown), and the adhesive can be mixed with the fluorescent material 1401 before being formed on the semiconductor light-emitting stack 13, or can The adhesive is first formed on the semiconductor light emitting stack 13, and then the fluorescent material 1401 is fixed on the semiconductor light emitting stack 13 by using the adhesive, and other structures ( not shown) is used to carry, fill or fix the fluorescent material 1401.

In addition, preferably, the fluorescent material structure 14 may only include the fluorescent material 1401, or be a non-glued fluorescent material structure (non-glued fluorescent material structure). and other materials with a bonding function to form a bulk fluorescent material, so the fluorescent material 1401 can be directly aggregated into a block to cover the semiconductor light emitting stack 13 . The method of directly polymerizing the fluorescent material 1401 can use such as deposition method (Sedimentation), or other thin film deposition methods, etc., and strengthen the cohesion between the fluorescent materials 1401 through appropriate polymerization procedures (such as: pressurization, heating, etc.), so that The fluorescent material 1401 is tightly bonded into a block and covers the semiconductor light emitting stack 13 . Since the fluorescent material structure 13 is directly aggregated into blocks by the fluorescent material 1401 , it is possible to avoid undue light absorption of adhesive materials such as adhesives or epoxy resins, thereby providing better light conversion efficiency and color performance.

Although the above-illustrated fluorescent material structure 14 is formed on the semiconductor light-emitting stack 13, it does not need to be in direct contact with the semiconductor light-emitting stack 13, and other structures (such as protective layers, optics, etc.) can also be formed on the semiconductor light-emitting stack 13. layer, etc.) and then form the fluorescent material structure 14. In addition, the fluorescent material 1401 can be a powder, preferably a sulfide powder, and the diameter of the powder can be between about 0.1-100 μm in order to obtain a preferred light conversion efficiency.

second embodiment

2a-2b show a schematic structural diagram of a semiconductor light-emitting device in another preferred embodiment of the present invention. The same components as those in the first embodiment will use the same reference numerals and will not be described again, and will be stated first.

As mentioned above, the bonding structure 12 is used to bond the opaque substrate 11 and the semiconductor light emitting stack 13 . In this embodiment, the bonding structure 12 may further include: a first intermediary layer 1201 , an adhesive layer 1202 and a second intermediary layer 1203 . The first interposer 1201 and the second interposer 1203 can be formed on the opaque substrate 11 and the semiconductor light-emitting stack 13 respectively, and then an adhesive layer 1202 is formed between the first interposer 1201 and the second interposer 1203 for adhesion. Combine the first interposer layer 1201 and the second interposer layer 1203 , and use the first interposer layer 1201 and the second interposer layer 1203 to increase the binding force between the adhesive layer 1202 and the opaque substrate 11 and the semiconductor light emitting stack 13 .

The material of the bonding layer 1202 in the bonding structure 12 can be polyimide (PI), benzocyclobutene (BCB), perfluorocyclobutene (PFCB) or other organic bonding materials. The material of the first interposer 1201 and the second interposer 1203 can be SiN _x , Ti, Cr or other materials that can increase the bonding force between the adhesive layer 1202 and the opaque substrate 11 and/or the semiconductor light emitting stack 13 .

Still referring to FIGS. 2 a and 2 b , the semiconductor light emitting element 10 of the present invention can also have a protective structure 15 disposed on the fluorescent material structure 14 to protect the fluorescent material structure 14 or other structures below it. The material of the protective structure 15 can be Su8, benzocyclobutene (BCB), epoxy resin (Epoxy), acrylic resin (Acrylic Resin), cycloolefin polymer (COC), polymethyl methacrylate (PMMA), Polyethylene terephthalate (PET), polycarbonate (PC), polyetherimide (Polyetherimide), fluorocarbon polymer (Fluorocarbon Polymer), silica gel (Silicone), glass, combinations of the above materials and others Light-transmitting materials.

The protection structure 15 may also include a plurality of optical layers 1501, 1502, and the plurality of optical layers 1501, 1502 have different thicknesses. 13, that is, the thickness of the outer layer is greater than the thickness of the inner layer, that is, the thickness of the optical layer 1502 is greater than that of the optical layer 1501. With this increasing thickness distribution, the temperature generated by the semiconductor light-emitting element 12 is higher than that of the protective structure. The thermal stress (Thermal Stress) caused on 15 can be relieved, and the protection structure 15 is prevented from being cracked due to the thermal stress. In addition, the plurality of optical layers 1501 , 1502 may be a diffuser layer, a light-gathering layer or other structures capable of adjusting the light-emitting properties of the semiconductor light-emitting element 10 .

In addition, the semiconductor light-emitting element 10 can also be provided with a reflective layer 16 to reflect light directed towards the opaque substrate 11 , so that most of the light travels toward the direction of the fluorescent material structure 14 . The reflective layer 16 can be disposed between the bonding structure 12 and the opaque substrate 11, and the bonding structure 12 is transparent at this time, as shown in FIG. 2a. Alternatively, the reflective layer 16 may be disposed between the bonding structure 12 and the semiconductor light emitting stack 13, as shown in FIG. 2b. Alternatively, the reflective layer 16 can be disposed in the semiconductor light emitting stack 13 (not shown), such as a Bragg Reflector or the like.

Wherein, the material of the reflective layer 16 may be metal, oxide, a combination thereof or other materials capable of reflecting light. Preferably, the material of the reflective layer 16 can be In, Sn, Al, Au, Pt, Zn, Ag, Ti, Pb, Ge, Cu, Ni, AuBe, AuGe, AuZn, PbSn, SiN _x , SiO ₂ , Al ₂ O ₃ , TiO ₂ , MgO or a combination of the above materials.

The semiconductor light emitting stack 13 of the present invention may also include a transparent conductive layer (not shown) to improve the effect of current spreading, or to form a preferred ohmic contact with other stacks. The material of this transparent conductive layer can be indium tin oxide (ITO), cadmium tin oxide (CTO), antimony tin oxide, zinc oxide, zinc tin oxide, Ni/Au, NiO/Au, TiWN, transparent metal layer, the above materials combination or other alternative materials.

third embodiment

1a～1c and 2a～2b, the manufacturing method of semiconductor light-emitting element 10 of the present invention can comprise: separating semiconductor light-emitting laminated layer 13 from an original growth substrate (not shown); Combining semiconductor light-emitting laminated layer 13 to opaque on the substrate 11; and forming a fluorescent material structure 14 on the semiconductor light emitting stack 13. In the bonding step, the semiconductor light-emitting stack 13 and the light-transmitting substrate 11 can be directly combined at an appropriate temperature and pressure; or a bonding structure 12 can be formed between the semiconductor light-emitting stack 13 and the light-proof substrate 11, and the bonding structure 12 can be It is an adhesive layer (not shown) to glue the semiconductor light-emitting stack 13 and the light-proof substrate 11; or the bonding structure 12 can be a metal (not shown), and the metal and the semiconductor light-emitting stack are made under a suitable temperature and pressure 13 is bonded with the opaque substrate 11 , and a mirror (not shown) may also be formed on the metal to reflect light toward the direction of the fluorescent material structure 14 .

Preferably, the bonding step includes: forming a first interposer 1201 on the opaque substrate 11; forming a second interposer 1203 on the semiconductor stack 13; stack 13, and make the adhesive layer 1202 between the first intermediary layer 1201 and the second intermediary layer 1203, the first intermediary layer 1201 and the second intermediary layer 1203 can be used to strengthen the adhesive layer 1202 and the opaque carrier 11 and semiconductor light emitting Bonding force between stacks 13.

In the method of the present invention, the fluorescent material structure 14 can preferably be formed above the semiconductor light emitting stack 13 by directly depositing (Sedimentation) the fluorescent material 1401, or the fluorescent material structure 14 can be formed by combining the fluorescent material 1401 with a binder (Binder; (not shown) are mixed and then formed on the semiconductor light emitting stack 13 .

Preferably, the method of the present invention can also arrange a protective structure 15 above the fluorescent material structure 14, and the protective structure 15 can include multi-layer structures 1501 and 1502, and the protective structure 15 can protect other structures under it or relieve high temperature caused by thermal stress.

Furthermore, the reflective layer 16 can also be formed between the opaque substrate 11 and the bonding structure 12, or the reflective layer 16 can be formed between the bonding structure 12 and the semiconductor light emitting stack 13, and the reflective layer 16 can also be formed, such as: Bragg A reflective layer, etc., is directly formed in the semiconductor light-emitting stack 12 to reflect light toward the direction of the fluorescent material structure 14

In addition, the method of the present invention can form the fluorescent material structure 14 on the wafer or crystal grain. If the fluorescent material structure 14 is formed on the wafer, the groove 1302 can be formed on the semiconductor light emitting stack 13 first, and then the semiconductor light emitting stack The fluorescent material structure 14 is formed on the fluorescent material structure 13 , and wafer dicing is performed after the fluorescent material structure 14 or the protection structure 15 is completed to form crystal grains of the semiconductor light emitting element 10 .

Although the present invention has been described above with specific embodiments, they are not intended to limit the present invention, and any modifications made by those skilled in the art will not deviate from what is intended to be protected by the appended claims.

Claims (10)

1. A semiconductor light emitting element, comprising at least: A semiconductor light emitting stack; a fluorescent material structure located on one side of the semiconductor light emitting stack; and An electrical contact is located in a vacancy of the fluorescent material structure and is in electrical contact with the semiconductor light emitting stack. 2. The semiconductor light emitting element according to claim 1, further comprising: An ohmic contact layer is located on the other side of the semiconductor light emitting stack. 3. The semiconductor light emitting element according to claim 1, further comprising: A reflective layer is located on the other side of the semiconductor light emitting stack. 4. The semiconductor light emitting element according to claim 1, further comprising: A metal structure is located on the other side of the semiconductor light emitting stack. 5. The semiconductor light emitting element according to claim 1, further comprising: A substrate is located on the other side of the semiconductor light emitting stack. 6. The semiconductor light emitting element according to claim 1, further comprising: A transparent substrate is located on the other side of the semiconductor light emitting stack. 7. The semiconductor light emitting element according to claim 1, further comprising: a substrate located on the other side of the semiconductor light emitting stack; and A combination structure is located between the semiconductor light emitting stack and the substrate. 8. The semiconductor light emitting device as claimed in claim 1, wherein the fluorescent material structure substantially conforms to the shape of the semiconductor light emitting stack. 9. The semiconductor light emitting device as claimed in claim 1, wherein the fluorescent material structure covers a part of a surface of the semiconductor light emitting stack. 10. A method for manufacturing a semiconductor light emitting element, comprising: forming a semiconductor light emitting stack on a substrate; forming a fluorescent material structure over the semiconductor light emitting stack; and An electrical contact is formed in a vacancy of the fluorescent material structure and is in electrical contact with the semiconductor light emitting stack.

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