TW200306020A - Light-emitting device and forming method thereof - Google Patents

Abstract

A light-emitting device and forming method thereof are disclosed. The light-emitting device has a rhombus shape and electrodes on the longer diagonal of the rhombus shape so that the light-emitting area is larger. The light-emitting device can be mounted to a substrate by a flip chip package process.

Description

200306020 V. Description of the invention α) 1. [Technical field to which the invention belongs] The present invention relates to a light-emitting diode element and a method for forming the same, particularly a light-emitting diode element having a high process yield and a large light-emitting area and Formation method. 2. [Previous Technology] In recent years, the development of the light-emitting diode industry is oriented towards Gallium N 1 tri de based semiconductors such as gallium nitride compound semiconductors, which are used to emit light in the wavelength range between green, blue and ultraviolet. Short-wavelength light-emitting diodes between lights. Short-wavelength light-emitting diodes can be used as green and blue light for full-color applications due to their high frequency or short wavelength. Blue- and purple-light-emitting diodes can be converted into white light sources through energy conversion. Conventionally, in order to increase the light emitting area of a gallium nitride / sapphire light emitting diode, electrode contacts are placed at both ends of a diagonal line to increase the light emitting area. However, in order to connect the electrode contacts with the outside world to drive the light emitting diode, the electrode contacts must be led through a metal pad (Contact Pads) or contact pads (Contact Pads) formed on the top of the light emitting diode. Such a design will cause the light-emitting area of the light-emitting diode to be shielded, especially when the light-emitting diode is viewed from the bottom, that is, the light-emitting area of the light-emitting diode becomes substantially smaller. In addition, this traditional structure is prone to cause excessive current concentration between the two metal pads, which can cause current congestion and affect component life. As mentioned above, this compound semiconductor light emitting diode must be an electrode

Page 6 200306020 V. Description of the invention (2) The contacts are placed at both ends of the diagonal line of the light-emitting surface. In order to connect the electrode contact with the outside to drive the light emitting diode, the electrode contact must be connected to the outside with a wire to drive the light emitting diode, and the volume of the electrode contact and the wire cannot be too small, so the light emitting diode will be caused. The light emitting area of the polar body is substantially reduced. In addition, when the size of the component is reduced, generally, a square-shaped light-emitting diode has its electrode contacts located at both ends of its diagonal. At this time, the electrode contacts will be very close and it will be easier to form a current congestion, which will affect the device characteristics, such as reliability. The degree of reduction is reduced, and the yield of the wire is reduced due to the excessive proximity of the electrodes. In addition, since the sapphire substrate system is a hexagonal crystal system (H e X a g ο n a 1 L a 11 i c e), cutting the light emitting diode into a square is likely to cause element splitting and reduce the process yield. In view of the shortcomings of the conventional component structures and processes described above, it is necessary to develop a novel and progressive component structure and process. This component structure and process can overcome the limitations of the conventional component structure and process. 3. [Content of the Invention] The technical problem to be solved by the present invention is to improve component cutting (

Scr i b i ng). The technical problem to be solved by the present invention is to provide a flip-chip packaged light emitting diode device with reduced size. The technical problem to be solved by the present invention is to provide a light-emitting diode device that still has a sufficient distance between electrodes when the device size is reduced.

Page 7 200306020 V. Description of the invention (3) The technical problem to be solved by the present invention is to provide a light emitting diode element with uniform brightness. The technical problem to be solved by the present invention is to provide a light emitting diode device manufacturing process capable of increasing production yield and yield. The technical problem to be solved by the present invention is to provide a light emitting diode element structure and manufacturing process with a large light emitting area under the same element size. In one embodiment, the technical solution to the problem of the present invention includes the following steps. A substrate is provided first, and then a first doped semiconductor layer having a first conductivity type is formed on the substrate. A light emitting active layer is then formed on the first doped semiconductor layer. A second doped semiconductor layer having a second conductivity type is then formed on the light emitting active layer. Then, a light-transmitting conductor layer is formed on the second doped semiconductor layer, and a plurality of first electrode patterns located at the longer diagonal ends of the plurality of first rhombus patterns are transferred into the light-transmitting conductor layer and the second The doped semiconductor layer and the light emitting active layer reach a predetermined depth of the first doped semiconductor layer, wherein one side of the first diamond pattern is parallel to the easy-to-split direction of the substrate. A dielectric layer is then formed to cover the substrate, and a plurality of the first and second electrode patterns located at two ends of the longer diagonals of the plurality of second rhombus patterns are transferred to the dielectric layer and the light is exposed. The conductor layer and the first doped semiconductor layer, wherein one side of the second diamond pattern is parallel to the easy-to-split direction of the substrate. And forming a plurality of first electrodes

200306020 V. Description of the invention (4) and a second electrode on the first doped semiconductor layer and the transparent conductor layer. A plurality of diamond-shaped components are cut along the easy-to-split direction of the substrate, and the first electrode and the second electrode of the component are connected to two component fixed electrodes by welding bumps by flip-chip packaging. Comparing the efficacy of the present invention with the prior art, since the traditional compound semiconductor light-emitting diode must be placed at both ends of the light-emitting diagonal with electrode contacts, the light-emitting area of the light-emitting diode will be substantially reduced and the brightness will be relatively Uneven. The invention utilizes the characteristics of the sapphire substrate lattice arrangement to cut the wafer along its easy-to-split lattice direction to form a light-emitting diode element with a diamond-shaped outline, so it can provide a light-emitting diode element with a large light-emitting area. At the same time, it can increase the production yield and output of light-emitting diode elements. In addition, due to the use of a flip-chip packaging process and placing the electrodes on the diagonal of the diamond-shaped outline. Therefore, smaller components can still be reliably manufactured as flip-chip components. The above description of the content of the invention and the following embodiments are merely examples and are not limiting. Other equivalent changes or modifications that do not depart from the spirit of the invention should be included in the patent scope of the invention. Fourth, [implementation] What must be explained here is that the process steps and structures described below do not include a complete process and structure. The present invention can be implemented by various process technologies, and only the process technologies required to understand the present invention are mentioned here.

Page 9 200306020 V. Description of the invention (5) The following detailed description will be based on the drawings attached to the present invention. Please note that the drawings are simple forms and are not drawn to scale, and the dimensions are exaggerated to facilitate understanding of the present invention. . Referring to FIG. 1A, a light emitting diode element 10 according to an embodiment of the present invention is shown. The light emitting diode element 10 includes a substrate 102, and a multilayer compound semiconductor structure, such as a gallium nitride-related compound semiconductor layer, can be formed on the substrate 102. The multilayer compound semiconductor layer may be formed by a metal organic chemical vapor deposition (MOCVD) method, but may also be formed by molecular beam epitaxy (MBE) or other chemical vapor deposition methods. The multilayer compound semiconductor layer includes semiconductor layers 106, 108, and 110. The light-emitting diode element further includes a light-transmitting conductive layer 104. The transparent conductive layer 104 is formed by a manufacturing process instead of a stupid crystal. The transparent conductive layer 4 is a transparent conductive layer (TCL), and the semiconductor layer 108 includes an active (light emitting) layer (Active Layer). The semiconductor layers 106 and 110 include semiconductor layers having opposite conductive properties (N-type or P-type), that is, the semiconductor layers 106 and Π0 may include a multilayer structure. This multi-layer structure may include an undoped semiconductor layer as a buffer layer or a cladding layer, or a combination of layers such as AlGaN / GaN and InGaN. The diamond-shaped light emitting diode element of the present invention can be formed by various processes. One method of formation is, for example, first to form a semiconductor using epitaxy

200306020 V. Description of the invention (6) Bulk layers 106, 108, and 1 10, and then etching a part of semiconductor layer 106, i 丨 〇, 丨 〇8, and 1 1 0 1 0 6 to form a groove to An electrode is received and the semiconductor layer 106 is connected, and then a light-transmitting conductive layer 104 and a transparent dielectric layer 112 are formed by a manufacturing process. Then, the electrodes are formed at both ends of the longer diagonal of the rhombus pattern, and finally the light emitting diode element of the present invention is formed by the cutting method shown in the first B figure. The light-emitting diode element having a diamond-shaped outline of the present invention can also be made by other forming methods. The electrodes 1 1 4, 1 1 6 and the conductor layer [1 8 shown in the first A are only examples, and are not limiting. The electrodes 1 1 4 and 1 1 6 may be formed using the same material and simultaneously, or different materials may be used. Even the electrodes 1 1 8 can be omitted. The diamond pattern and electrodes can be formed using photomask, lithography, and etching processes. The electrodes π 4 and i 6 and 1 18 and the light-transmitting conductive layer 104 can be formed by lithography and physical / chemical deposition methods or traditional evaporation methods. The dielectric layer 1 12 separates the semiconductor layer 106 from the semiconductor layer 106. The semiconductor layers 106 and 110 are connected to the driving circuit through the electrodes 1 16 and 1 1 4. The dielectric layer 1 12 may be a silicon dioxide layer, but is not limited to a silicon dioxide layer, such as a silicon nitride or a transparent polymer layer. The dielectric layer 1 12 can be formed by lithography, coin engraving, chemical vapor deposition, or traditional vapor deposition. The dielectric layer 1 1 2 is necessary for a flip-chip device, but may be omitted for a non- flip-chip device. If a gallium nitride (G a N) compound semiconductor is used, the substrate 102 includes a sapphire substrate of Hexagona1 Lattice. The semi-amplifier layers 106 and 110 include a first #hetero gallium nitride semiconductor layer having a first conductivity type and a second doped gallium nitride semiconductor layer having a second conductivity type. The semiconductor layers 106 and 11 may include undoped nitride 豕 buffer layer or cladding layer at the same time.

Page 11 200306020 V. Description of invention (7) layer. The semiconductor layers 106 and 110 are N-type layers and P-type layers, and the electrodes 1 4 and 116 are P-type electrodes and N-type electrode layers. In addition, the substrate 102 may be a silicon carbide (S i C) substrate or other high-temperature-resistant and transparent substrate.

Referring to FIG. 1B, a top view of a wafer 1 including the light-emitting diode element 10 shown in FIG. 1A is shown. The light-emitting diode element 10 shown in the first picture A has a plan view of a rhombic shape, and the electrodes 1 1 4 and 1 1 8 are located at both ends of a longer diagonal line, as shown in the first picture C. The first D picture and the first E picture show electrodes 1 1 4 and 1 1 8 having different configurations. The electrode Π 4 shown in the first figure D has two extension regions, so that the distance between the electrodes 1 1 4 and 1 1 8 is not too large no matter where it is. The electrodes 1 1 4 and 1 1 8 shown in the first E diagram each have an extended area, so that the distance between the electrodes Π 4 and 1 1 8 is very uniform everywhere. In order to facilitate cutting, a groove may be formed on the cutting line shown in Fig. _C of the light emitting diode element. Referring to FIG. 1F, the light emitting diode element 10 of the present invention is fixed to the element fixing electrodes 12 and 14 with bumps 16 and 18. The electrodes 12 and 14 are connected to a circuit, so that the light emitting diode element of the present invention becomes a light emitting diode lamp (Lamp). The light-emitting diode element 10 is packaged in a flip-chip (F1 ip chip) package, and electrodes 1 1 4 and 1 1 8 are connected to the bumps 16 and 8 respectively. However, the above structure is not limited to the combination by flip-chip packaging, and can also be joined by Surface Mounting technology. The electrodes 1 1 8 shown in Fig. 1a are not necessary and may be omitted. The bumps 16 and 18 in the first F picture can also be replaced by conductive glue. The above structure is not limited to flip chip sealing

The light and shrinkage of the small elementary body of Yiyuan No. 2 Elementary School is the second best rule for making light parts far from the crystal. It can be used to make parts that are far from the light. The profile system and the crystal uniformity of the wheel poles cover the uniform shape of the cells, and the efficiency of the row of diamonds and the body makes the bright grid active when the light crystal surface. The hairline of the lb outer line is greatly increased by Γ1 and the other angle C is increased and S is increased. With blue circle can C plug contour. When using the crystal supply, the cutting wheel is cut to cut the same-cut manifold element and cut the energy. It is the electric diamond equipment to send to this piece. Do not avoid sealing the side due to the special element to avoid crystal cracks. 200306020 when measuring electricity V. Description of the invention (8) The combination of mounting methods can also be combined by Surface Mounting technology. Referring to FIG. 1G, the light-emitting diode element 10 of the present invention is fixed on the electrode contact pad 12 of the circuit board 12 2 in a flip-chip package. The electrode contact pad 1 2 0 is connected to the circuit. . The light-emitting diode element 10 is in a flip-chip package, and the electrodes 1 4 and 1 1 8 are respectively bonded to the contact pad 1 2 0 by soldering or conductive glue, and the bumps 16 and 18 can also be connected. The above structure is not limited to being bonded in a flip-chip package, and can also be bonded by surface adhesion technology. The above detailed description of the invention is merely an example and not a limitation. Other equivalent changes or modifications that do not depart from the spirit of the invention should be included in the patent scope of the invention.

Page 13 200306020 Brief description of the drawings V. [Simplified description of the drawings] In order to make the other objects, features, and advantages of the present invention more obvious and understandable, a preferred embodiment is given below in conjunction with the attached The drawings are described in detail as follows: FIG. 1A shows a semiconductor light-emitting diode device according to an embodiment of the present invention; FIG. 1B shows a crystal including the semiconductor light-emitting diode device shown in FIG. A top plan view of a circle, a first C view shows a top view of a semiconductor light emitting diode element according to an embodiment of the present invention; a first D view shows a top view of a semiconductor light emitting diode element according to another embodiment of the present invention; a first E view shows A top view of a semiconductor light emitting diode element according to another embodiment of the present invention; the first F image shows that the semiconductor light emitting diode element of the present invention is fixed on the element fixing electrode by a flip-chip package; and the first G image The semiconductor light emitting diode device of the present invention is shown by

Page 14 200306020 The diagram simply illustrates the way the crystal package is fixed to the main symbols of the circuit board: 1 wafer 1 0 light emitting diode element 1 2 electrode 1 4 electrode 1 6 bump 1 8 bump 1 0 2 substrate 1 0 4 light-transmitting conductor layer 1 0 6 semiconductor layer 1 0 8 active (light-emitting) conductor layer 1 1 0 semiconductor layer 1 1 2 dielectric layer 1 1 4 electrode 1 1 6 electrode 1 1 8 conductor layer 12 0 Electrode contact pad 1 2 2 circuit board

Page 15

Claims (1)

200306020 6. Scope of patent application 1. A light-emitting diode element, the light-emitting diode element includes: a substrate; a multilayer compound semiconductor structure having a diamond-shaped profile, the multilayer compound semiconductor structure is located on the substrate, wherein A pair of parallel sides of the diamond-shaped contour is parallel to the easy-to-split direction of the substrate; and a first and a second electrode located at the two ends of the longer diagonal of the diamond-shaped contour, respectively, to make the current distribution uniform. 2. The light-emitting diode device according to item 1 of the scope of patent application, wherein the substrate mentioned above comprises a sapphire substrate. 3. The light-emitting diode device according to item 1 of the scope of patent application, wherein the multilayer compound semiconductor structure described above comprises: a first doped semiconductor layer of a first conductivity type on the substrate; a light-emitting active layer On the first doped semiconductor layer; a second doped semiconductor layer with a second conductivity type on the light-emitting active layer; a light-transmitting conductor layer on the second doped semiconductor layer; a diamond shape A groove at one end of a longer diagonal line, the groove being deep into the first doped semiconductor layer to accommodate the second electrode and connected to the first doped semiconductor layer and exposing a portion of the second doped semiconductor Layer, part of the light emitting active layer and part of the first doped semiconductor layer; and a dielectric layer covering the light-transmitting conductor layer, the exposed second doped semiconductor layer, the exposed light emitting active layer and The exposed first doped semiconductor layer Page 16 200306020 6. Scope of patent application to isolate the first electrode from the second electrode. 4. The light-emitting diode device according to item 3 of the scope of the patent application, wherein the first doped semiconductor layer and the second doped semiconductor layer comprise a Group III compound semiconductor layer. 5. The light emitting diode device according to item 3 of the scope of the patent application, wherein the first doped semiconductor layer and the second doped semiconductor layer comprise a gallium nitride doped semiconductor layer. 6. The light-emitting diode device according to item 3 of the scope of the patent application, wherein the dielectric layer includes a dioxide layer, but is not limited to a dioxide layer. 7. The light emitting diode device according to item 3 of the scope of patent application, wherein the dielectric layer comprises a silicon nitride. 8. The light-emitting diode device according to item 3 of the scope of patent application, wherein the dielectric layer comprises a transparent polymer layer. 9. The light-emitting diode device according to item 3 of the scope of patent application, wherein the first doped semiconductor layer and the second doped semiconductor layer are an N-type doped semiconductor layer and a P-type doped semiconductor layer. . 1 0. The light-emitting diode element described in item 1 of the patent application scope further includes two Page 17 200306020 6. Scope of patent application The bumps formed on the first electrode and the second electrode are used for flip-chip packaging, respectively. 1 1. The light-emitting diode element according to item 1 of the scope of patent application further includes two bumps formed on the first electrode and the second electrode respectively for surface adhesive bonding. 12. The light-emitting diode element as described in item 1 of the scope of patent application further comprises two conductive pastes formed on the first electrode and the second electrode respectively for chip-on-chip packaging. 1 3. The light-emitting diode element according to item 1 of the scope of patent application further comprises two conductive adhesives formed on the first electrode and the second electrode respectively for surface adhesive bonding. 1 4. A method for forming a light-emitting diode element. The method for forming a light-emitting diode element includes at least the following steps: providing a substrate; forming a first doped semiconductor layer having a first conductivity type on the substrate; Forming a light-emitting active layer on the first doped semiconductor layer; forming a second doped semiconductor layer having a second conductivity type on the light-emitting active layer; forming a light-transmitting conductor layer on the second On the doped semiconductor layer; Page 18 200306020 VI. Patent application scope Transfer of a plurality of first electrode patterns located at the longer diagonal end of the plurality of first rhombus patterns into the light-transmitting conductor layer, the second doped semiconductor layer and the light-emitting active layer To a predetermined depth of the first doped semiconductor layer, wherein one side of the first diamond pattern is parallel to the cleavage direction of the sapphire substrate; a dielectric layer is formed to cover the substrate; the transfer is located in a plurality of second diamonds The plurality of first and second electrode patterns at the two ends of the longer diagonal line to the dielectric layer expose the transparent conductive layer and the first doped semiconductor layer, and one side of the second diamond pattern Parallel to the easy-to-split direction of the substrate; forming a plurality of first electrodes and second electrodes on the first doped semiconductor layer and the light-transmitting conductive layer; and cutting a plurality of along the easy-to-split direction of the substrate Diamond-shaped element. 15. The method for forming a light-emitting diode element according to item 14 of the scope of patent application, wherein the substrate described above comprises a sapphire substrate. 16. The method for forming a light-emitting diode device according to item 14 of the scope of the patent application, wherein the first doped semiconductor layer and the second doped semiconductor layer are formed by metal organic chemical vapor deposition ( MOCVD) method. 17. The method for forming a light-emitting diode device according to item 14 of the scope of patent application, wherein the first doped semiconductor layer and the second doped semiconductor are described above. 200306020 6. Scope of patent application The bulk layer is formed by molecular beam epitaxy (MBE). 18. The method for forming a light emitting diode device according to item 14 of the scope of patent application, wherein the first doped semiconductor layer and the second doped semiconductor layer include a gallium nitride doped semiconductor layer. 19. The method for forming a light-emitting diode device as described in item 14 of the scope of the patent application, wherein the dielectric layer described above includes a dioxide layer. 20. The method for forming a light-emitting diode device according to item 14 of the scope of patent application, wherein the dielectric layer includes a nitride. 2 1. The method for forming a light-emitting diode device according to item 14 of the scope of patent application, wherein the dielectric layer described above includes a transparent polymer layer. 2 2. The method for forming a light-emitting diode device according to item 14 of the scope of the patent application, wherein the first doped semiconductor layer and the second doped semiconductor layer are an N-type doped semiconductor layer and P Type doped semiconductor layer. 2 3. The method for forming a light-emitting diode device according to item 14 of the scope of the patent application, wherein the first doped semiconductor layer and the second doped semiconductor layer described above include a group III or compound semiconductor layer. 2 4. The light emitting diode element as described in item 14 of the scope of patent application Page 20 200306020 VI. Patent application method, wherein the first doped semiconductor layer and the second doped semiconductor layer include a gallium nitride doped semiconductor layer. 25. The method for forming a light-emitting diode element as described in item 14 of the scope of the patent application further includes forming bumps on the first electrode and the second electrode, respectively, for flip-chip packaging. 26. The light-emitting diode element as described in item 14 of the scope of patent application further comprises forming bumps on the first electrode and the second electrode, respectively, for surface adhesive bonding. 2 7. The light-emitting diode element as described in item 14 of the scope of the applied patent further comprises forming a conductive paste on the first electrode and the second electrode to perform flip-chip packaging. 28. The light-emitting diode element as described in item 14 of the scope of patent application further comprises forming a conductive paste on the first electrode and the second electrode to perform surface adhesive bonding. Page 21