TWI715108B - Micro light emitting diode structure and the manufacturing method thereof - Google Patents

Abstract

The present invention discloses a micro light emitting diode structure, comprising a substrate, a light emitting diode unit, a first electrode and a second electrode. The light emitting diode unit is disposed on the substrate, comprising a first semiconductor layer, a second semiconductor layer disposed on the first semiconductor layer, an emitting layer disposed between the first semiconductor layer and the second semiconductor layer, and a plurality of gaps. Each gap is communicated from the first semiconductor layer to the second semiconductor layer. The first electrode is disposed on the first semiconductor layer, comprising a first major electrode and a plurality first sub-electrodes. The second electrode is disposed on the second semiconductor layer, comprising a second major electrode and a plurality second sub-electrodes.

Description

Micro light emitting diode structure and manufacturing method thereof

The present invention provides a micro-light-emitting diode structure and a manufacturing method thereof, in particular to a micro-light-emitting diode structure and a manufacturing method thereof in which the light-emitting diode unit is cut by laser so that the light emission of each element can be controlled independently.

Micro light emitting diode (Micro light emitting diode) display technology is a new generation of light emitting and display technology. The principle is to reduce the size of the light-emitting diode to below 100 microns (about 1% of the original light-emitting diode) through the design of the light-emitting diode structure for thin film, miniaturization and arraying. After the layers are stacked in a physical way, the substrate is packaged to fabricate micro-light-emitting diode devices of various sizes and simple structures. After the overall module is reduced, the image quality and response speed are improved. Therefore, the micro light emitting diode has many advantages such as high resolution, color saturation, large visual angle, fast response speed, power saving and long life.

In addition to replacing traditional liquid crystal displays and light-emitting diodes as panel displays, miniature light-emitting diodes have the advantage of super power saving. They are also suitable for use in wearable device screens, electronic signage, head-up displays (HUD), and head-mounted displays. Micro devices such as embedded displays (HMD). However, the current miniature light-emitting diodes have not yet been able to independently control the light-emitting layers of each element, and the electrode configuration also has problems such as uneven current diffusion, which affects the light-emitting brightness.

In view of this, the present invention proposes a miniature light-emitting diode structure and a manufacturing method thereof. The interdigitated electrode structure allows the current to spread uniformly; and the light-emitting diode unit is cut through a laser method to make the miniature light-emitting diode The light emission of the light emitting diode unit in the bulk structure can be independently controlled.

A miniature light-emitting diode structure provided by the present invention includes: a substrate; a light-emitting diode unit formed on the substrate, and the light-emitting diode unit includes: a first semiconductor layer; a second semiconductor layer , Formed on the first semiconductor layer; an active layer formed between the first semiconductor layer and the second semiconductor layer; and a plurality of gaps formed on the light emitting diode unit, and each gap is formed by The first semiconductor layer is connected to the second semiconductor layer; and a first electrode disposed on the first semiconductor layer, the first electrode including a first main electrode and a plurality of first sub-electrodes; and a second The electrode is arranged on the second semiconductor layer, and the second electrode includes a second main electrode and a plurality of second sub-electrodes. Wherein, each gap is between the plurality of adjacent first sub-electrodes and the plurality of second sub-electrodes.

Another miniature light-emitting diode structure proposed by the present invention includes: a substrate; a plurality of light-emitting diode units are formed on the substrate, wherein each light-emitting diode unit includes: a first semiconductor layer; The second semiconductor layer is formed on the first semiconductor layer; an active layer is formed between the first semiconductor layer and the second semiconductor layer; and a plurality of gaps are formed on the light emitting diode unit, and each A gap is connected from the first semiconductor layer to the second semiconductor layer; a first electrode arranged on the second semiconductor layer of the first light emitting diode unit of the plurality of light emitting diode units; at least one connecting electrode , Arranged between two adjacent light-emitting diode units in the plurality of light-emitting diode units, wherein one end of each connecting electrode is arranged at the first of one of the two adjacent light-emitting diode units On a semiconductor layer, the other end of which is arranged on the other of the two adjacent light-emitting diode units On the first semiconductor layer or the second semiconductor layer of a light emitting diode unit; and a tail electrode disposed on the first semiconductor layer or the second semiconductor layer of the last light emitting diode unit of the plurality of light emitting diode units Layer up. Wherein, the first electrode, each connecting electrode and the tail electrode respectively include a main electrode and a plurality of sub-electrodes; wherein, each of the gaps on each light-emitting diode unit is between the adjacent plurality of sub-electrodes between.

In addition, the present invention further provides a method for manufacturing a micro light emitting diode structure, including the following steps: (A) setting a substrate; (B) forming a first semiconductor layer on the substrate; (C) forming an active layer on the substrate On the first semiconductor layer; (D) forming a second semiconductor layer on the active layer; (E) cutting the first semiconductor layer, the active layer and the second semiconductor layer with a laser to form a plurality of wires The first semiconductor layer is connected to the gap of the second semiconductor layer; (F) disposing a first electrode on the first semiconductor layer, the first electrode including a first main electrode and a plurality of first sub-electrodes; and (G) Disposing a second electrode on the second semiconductor layer, the second electrode including a second main electrode and a plurality of second sub-electrodes, and each gap is between the adjacent first sub-electrodes Between the electrode and the plurality of second sub-electrodes.

100A: Formal-mounted miniature light-emitting diode structure

100B: flip-chip micro light emitting diode structure

100C: Vertical miniature light-emitting diode structure

110: substrate

115: conductive substrate

120: LED unit

130: first semiconductor layer

140: second semiconductor layer

150: active layer

160: first electrode

161: first main electrode

163: first sub-electrode

170: second electrode

171: second main electrode

173: second sub electrode

180: Pedestal

190: gap

195: buffer layer

196: conductive adhesive layer

200, 300: Miniature LED structure

210, 310: substrate

220, 320: LED unit

230, 330: the first semiconductor layer

240, 340: second semiconductor layer

250, 350: active layer

260, 360: tail electrode

270, 370: first electrode

271, 371: Main electrode

273, 373: Sub-electrodes

280, 380: connecting electrodes

290, 390: Gap

H: interval

(A)-(G): steps

Fig. 1A is a side view of the front-mounted micro light emitting diode structure of the first embodiment of the present invention.

Fig. 1B is a side view of the flip-chip micro light emitting diode structure of the first embodiment of the present invention

Figure 2A is a top view of the front-mounted micro light emitting diode structure of the first embodiment of the present invention.

The second figure B is a top view of the flip-chip micro light emitting diode structure of the first embodiment of the present invention.

The third figure is a side view of the micro light emitting diode structure of the second embodiment of the invention.

The fourth figure is a top view of the micro light emitting diode structure of the second embodiment of the present invention.

Figure 5 is a side view of the micro light emitting diode structure of the third embodiment of the present invention.

The sixth figure is a top view of the micro light emitting diode structure of the third embodiment of the present invention.

The seventh figure is a side view of the micro light emitting diode structure of the fourth embodiment of the present invention.

The eighth figure is the manufacturing method of the micro light emitting diode structure according to the preferred embodiment of the present invention.

In order to understand the technical features and practical effects of the present invention, and to implement it in accordance with the content of the specification, the preferred embodiment shown in the figure is further described in detail as follows:

The purpose of the present invention is to provide a micro-light-emitting diode structure and a micro-light-emitting diode structure in which the light-emitting diode unit in the micro-light-emitting diode structure is cut by laser so that the cut light-emitting diode unit can be independently controlled to emit light Its production method.

First, please refer to the first A and the second A, which are the side view and the top view of the front-mounted micro light emitting diode structure of the first embodiment of the present invention. In this embodiment, the micro light-emitting diode structure 100A includes: a substrate 110; a light-emitting diode unit 120 formed on the substrate 110, and the light-emitting diode unit 120 includes: a first semiconductor layer 130 A second semiconductor layer 140 is formed on the first semiconductor layer 130; an active layer 150 is formed between the first semiconductor layer 130 and the second semiconductor layer 140; and a plurality of gaps 190 are formed on the On the surface of the light emitting diode unit 120, and each gap 190 is connected to the second semiconductor layer 140 from the first semiconductor layer 130; and a first electrode 160 is disposed on the first semiconductor layer 130, the The first electrode 160 includes a first main electrode 161 And a plurality of first sub-electrodes 163; and a second electrode 170 disposed on the second semiconductor layer 140. The second electrode 170 includes a second main electrode 171 and a plurality of second sub-electrodes 173. Wherein, each gap 190 is between the plurality of adjacent first sub-electrodes 163 and the plurality of second sub-electrodes 173.

It can be seen from the first figure A that the micro light emitting diode structure 100A belongs to a front-mounted micro light emitting diode structure. Specifically, the front-mounted micro light emitting diode structure 100A has a substrate 110, the substrate has a surface and a bottom surface, and the surface and the bottom surface are disposed opposite to the bottom surface. Wherein, the substrate 110 is not limited to a single material, but may also be a composite substrate composed of a plurality of different materials. For example, the substrate 110 may be two first substrate and second substrate (not shown in the figure). Show). In this embodiment, the material of the substrate 110 is sapphire; and in other possible embodiments, the material of the substrate 110 can also be but not limited to lithium aluminum oxide (LiAlO ₂ ), zinc oxide ( zinc oxide, ZnO), gallium phosphide (GaP), glass (Glass), organic polymer sheet, aluminum nitride (AlN), gallium arsenide (GaAs), diamond (diamond) , Quartz (quartz), silicon (silicon, Si), silicon carbide (SiC) or diamond like carbon (DLC); in addition, the material of the substrate 110 can be, but not limited to, methyl Methyl acrylate (PMMA), polyethylene terephthalate (PET), polycarbonate (PC), polyimide (PI), polyethylene naphthalate (PEN), cyclic olefin copolymer Flexible plastic materials and composite materials such as COC or PA.

Next, a light emitting diode unit 120 is formed on the surface of the substrate 110. The manufacturing method of the light emitting diode unit 120 is as follows: first, an epitaxial stack is formed on a growth substrate (not shown) by a conventional epitaxial growth process, including: a first semiconductor layer 130; The active layer 150 formed on the first semiconductor layer 130 and the second semiconductor layer 140 formed on the active layer 150. The material of the growth substrate can include but is not limited to gallium arsenide (GaAs), germanium (Ge), indium phosphide (InP), sapphire (sapphire), silicon carbide (SiC), silicon ), lithium aluminum oxide (LiAlO ₂ ), zinc oxide (ZnO), gallium nitride (GaN), aluminum nitride (AlN).

Furthermore, a part of the epitaxial stack is selectively removed by the yellow light lithography process technology to form the epitaxial stack of the light emitting diode unit 120 on the growth substrate. Wherein, it may further include forming the exposed area of the first semiconductor layer 130 in the light emitting diode unit 120 by yellow light lithography process technology to serve as a platform for subsequent electrode structure configuration.

In addition, in addition to the first semiconductor layer 130 and the second semiconductor layer 140, one or more semiconductor layers of the same or different composition may be placed between the substrate 110 and the first semiconductor layer 130 according to different functional characteristics, such as A buffer layer is formed between the substrate 110 and the first semiconductor layer 130 to serve as a stress relaxation layer during epitaxial growth between the substrate 110 and the first semiconductor layer 130. In addition, the second semiconductor layer 140 may be a transparent oxide metal layer formed on the active layer, and one or more third semiconductor layers may be included between the second semiconductor layer 140 and the active layer 150. The oxide metal layer has a better lateral current diffusion rate, which can be used to assist the uniform diffusion of current into the underlying semiconductor layer. Taking this embodiment as an example, indium tin oxide is used as the transparent oxide metal layer. Other material options can also include zinc oxide (ZnO), indium oxide (InO), tin oxide (SnO ₂ ), tin fluorine oxide (FTO) ), antimony tin oxide (ATO), cadmium tin oxide (CTO), zinc aluminum oxide (AZO), cadmium doped zinc oxide (GZO), or a combination thereof.

In order to increase the light extraction efficiency of the whole structure, the light emitting diode unit 120 can be disposed on the substrate 110 through the technology of substrate transfer or substrate bonding. The light emitting diode unit 120 can be directly bonded to the substrate 110 by heating or pressing, or the light emitting diode unit 120 and the substrate 110 can be adhesively bonded through a transparent adhesive layer. Among them, the transparent adhesive layer can be an organic polymer transparent adhesive material, such as polyimide (polyimide), benzocyclobutene polymer (BCB), perfluorocyclobutyl polymer (PFCB), epoxy resin (Epoxy), acrylic resin (Acrylic Resin), polyester resin (PET), polycarbonate resin (PC) or a combination thereof; or a transparent conductive metal oxide layer, such as indium tin oxide (ITO), Indium oxide (InO), tin oxide (SnO ₂ ), zinc oxide (ZnO), tin fluorine oxide (FTO), antimony tin oxide (ATO), cadmium tin oxide (CTO), zinc aluminum oxide (AZO), doped Cadmium zinc oxide (GZO) or a combination thereof; or an inorganic insulating layer, such as aluminum oxide (Al ₂ O ₃ ), silicon nitride (SiN _x ), silicon oxide (SiO ₂ ), aluminum nitride (AlN), titanium dioxide ( TiO ₂ ), Tantalum Pentoxide (Ta ₂ O ₅ ), or a combination thereof.

Specifically, the method of arranging the light-emitting diode unit 120 on the substrate 110 is not limited to this. Those with ordinary knowledge in the art should understand that the light-emitting diode unit 120 can also be used according to different structural characteristics. The method of epitaxial growth is directly formed on the substrate. In addition, depending on the number of times the substrate is transferred, the second semiconductor layer 140 can also be formed adjacent to the surface of the substrate 110, and the first semiconductor layer 130 is formed on the second semiconductor layer 140 with an active layer 150 in between.

In this embodiment, each gap 190 is formed by laser cutting from the first semiconductor layer 130 (close to the side of the first electrode 160) to the second semiconductor layer 140 (close to the side of the second electrode 170)的 gap 190. Finally, a first electrode 160 is formed on the first semiconductor layer 130 by sputtering, and a second electrode 170 is formed on the second semiconductor layer 140; wherein the first electrode 160 includes a first main electrode 161 And a plurality of first sub-electrodes 163, the second electrode 170 includes a second main electrode 171 and a plurality of second sub-electrodes 173.

The aforementioned first electrode 160 and the second electrode 170 are interdigitated electrode structures, and each of the first sub-electrodes 163 included in the first electrode 160 is parallel to each other and at equal intervals (or unequal intervals). Sequentially arranged on the first main electrode 161, and each second sub-electrode included in the second electrode 170 173 are also arranged in sequence on the second main electrode 171 in parallel with each other and at equal intervals (or unequal intervals). The actual arrangement, angle and spacing of the plurality of first sub-electrodes 163 and the plurality of second sub-electrodes 173 can be arbitrarily changed according to the needs of the user, and the present invention is not limited.

Furthermore, each gap 190 cut by the laser on the light emitting diode unit 120 is between the adjacent first sub-electrodes 163 and the second sub-electrodes 173. In addition, please refer to the top view of Figure 2A at the same time. Each of the first sub-electrodes 163 included in the first electrode 160 has only a partial area disposed on the first semiconductor layer 130 (ie, the first semiconductor layer 130 only has a partial area in contact with the first sub-electrode 163), and each second sub-electrode 173 included in the second electrode 170 also has only a partial area disposed on the second semiconductor layer 140 (ie, the second semiconductor layer 140 Only a part of the area is in contact with the second sub-electrode 173). The above structure is characterized in that there is a gap H between the first main electrode 160 and the first semiconductor layer 130, and the second main electrode 171 and the second semiconductor layer 140 There is also a gap H between them. In other words, the gap H between the two sides of the micro light emitting diode structure 100 is also the starting and ending point of each gap 190 (as shown by the dotted line in the second A). Thereby, each of the light-emitting diode unit 120 is divided into the first semiconductor layer 130, the active layer 150, and the second semiconductor layer 140 by the gap 190, which can be controlled by the first electrode 160 and the second electrode 170. The independent first semiconductor layer 130, the active layer 150 and the second semiconductor layer 140 achieve the purpose of independently controlling the light emission of the light emitting diode unit 120.

Furthermore, the laser cutting used in this embodiment can be combined with plasma etching through the laser cutting method of Nanosecond Laser, Femtosecond Laser or Picosecond Laser. The combination of technologies forms a plurality of gaps 190 on the LED unit 120. Specifically, lasers with wavelengths in the visible spectrum plus ultraviolet (UV) and infrared (IR) ranges can be used to provide lasers based on nanoseconds, picoseconds, or femtoseconds, that is, they have the order of nanoseconds ( 10 ^-9 seconds), picosecond (10 ^-12 seconds) or femtosecond (10 ^-15 seconds) pulse width laser; through nanosecond, picosecond or femtosecond laser cutting methods, it can be effectively used in A plurality of gaps 190 are formed on the light emitting diode unit 120. The difference between the three lasers is that the use of a laser with a pulse width in the femtosecond range alleviates or eliminates the thermal damage that may be caused by the nanosecond laser. The engraving method using the femtosecond laser can be more accurate and complete.的 gap 190.

In addition, the structure of the micro light emitting diode 100 of this embodiment further includes at least one wire (not shown), and the at least one wire is erected on the substrate 110 or even connected to an external circuit outside the substrate 110. At least one wire can be electrically connected to the first electrode 160 and the second electrode 170, so that the user can control the external circuit to independently control each of the first and second sub-electrodes 160 and 170. The luminescence of independent components. Wherein, the material of the aforementioned at least one wire and the first electrode 160 and the second electrode 170 may be gold (Au), silver (Ag), copper (Cu), chromium (Cr), aluminum (Al), platinum (Pt) , Nickel (Ni), titanium (Ti), tin (Sn) or their alloys and their laminate combinations.

On the other hand, please refer to the first B and the second B, which are the side view and the top view of the flip-chip micro light emitting diode structure of the first embodiment of the present invention. In this embodiment, the micro light-emitting diode structure 100B includes: a base 180; a first electrode 160 and a second electrode 170, disposed on the surface of the base 180, and the first electrode 160 includes a A first main electrode 161 and a plurality of first sub-electrodes 163. The second electrode 170 includes a second main electrode 171 and a plurality of second sub-electrodes 173; a light emitting diode unit 120 is disposed on the first electrode 160 and the second electrode 170, the light emitting diode unit 120 includes: a second semiconductor layer 140 disposed on a part of the surface of the second electrode 170; an active layer 150 disposed on the second semiconductor layer 140 On the surface; a first semiconductor layer 130 is configured on the active layer 150 and part of the surface of the first electrode 160; and a substrate is configured on the surface of the first semiconductor layer 130. Wherein, the light emitting diode unit 120 further includes a plurality of gaps, and each gap 190 is formed by The first semiconductor layer 130 is connected to the second semiconductor layer 140, and each gap 190 is between the plurality of adjacent first sub-electrodes 163 and the plurality of second sub-electrodes 173.

It can be seen from the first figure B that the micro light emitting diode structure 100B belongs to a flip-chip micro light emitting diode structure. Specifically, the manufacturing method of the flip-chip micro light-emitting diode structure 100B is substantially the same as that of the front-mounted micro light-emitting diode structure 100A in Figure 1A. First, a substrate 110 is also provided. The substrate has a surface and a bottom surface, and the surface and the bottom surface are disposed oppositely. The material of the substrate 110 is blue sapphire in this embodiment.

Next, also on the surface of the substrate 110, a light emitting diode unit 120 is formed. The manufacturing method of the light emitting diode unit 120 is as follows: first, an epitaxial stack is formed on a growth substrate (not shown) by a conventional epitaxial growth process, including: a first semiconductor layer 130; The active layer 150 formed on the first semiconductor layer 130 and the second semiconductor layer 140 formed on the active layer 150. The material of the growth substrate can include but is not limited to gallium arsenide (GaAs), germanium (Ge), indium phosphide (InP), sapphire (sapphire), silicon carbide (SiC), silicon ), lithium aluminum oxide (LiAlO ₂ ), zinc oxide (ZnO), gallium nitride (GaN), aluminum nitride (AlN).

Furthermore, a part of the epitaxial stack is selectively removed by the yellow light lithography process technology to form the epitaxial stack of the light emitting diode unit 120 on the growth substrate. Wherein, it may further include forming the exposed area of the first semiconductor layer 130 in the light emitting diode unit 120 by yellow light lithography process technology to serve as a platform for subsequent electrode structure configuration.

The following steps are different from the front-mounted micro light emitting diode structure 100A. After the light-emitting diode unit 120 is formed on the surface of the substrate 110, it is laser-cut from the first semiconductor layer 130 (close to the side of the first electrode 160) to the second semiconductor layer 140 (close to the side of the second electrode 170) side) To form a plurality of gaps 190 (the laser does not cut to the substrate 110, in other words, the substrate 110 does not have any gaps). Finally, the light-emitting diode unit 120 formed on the substrate 110 and having a plurality of gaps 190, together with the substrate 110, is flip-chip mounted on the first electrode 160 and the second electrode 170 on the base 180 to complete the inversion of this embodiment. Mounted micro light emitting diode structure 100B.

The aforementioned first electrode 160 and the second electrode 170 are interdigitated electrode structures, and each of the first sub-electrodes 163 included in the first electrode 160 is parallel to each other and at equal intervals (or unequal intervals). Are arranged in sequence on the first main electrode 161, and each of the second sub-electrodes 173 included in the second electrode 170 is also arranged in sequence on the second main electrode in parallel and equidistant (or unequal pitch). On the electrode 171. The actual arrangement, angle and spacing of the plurality of first sub-electrodes 163 and the plurality of second sub-electrodes 173 can be arbitrarily changed according to the needs of the user, and the present invention is not limited.

Furthermore, each gap 190 cut by the laser on the light emitting diode unit 120 is between the adjacent first sub-electrodes 163 and the second sub-electrodes 173. In addition, please also refer to the top view of the second figure B. Each of the first sub-electrodes 163 included in the first electrode 160 has only a partial area disposed on the first semiconductor layer 130 (ie, the first semiconductor layer 130 only has a partial area in contact with the first sub-electrode 163), and each second sub-electrode 173 included in the second electrode 170 also has only a partial area disposed on the second semiconductor layer 140 (ie, the second semiconductor layer 140 Only a part of the area is in contact with the second sub-electrode 173). The above structure is characterized in that there is a gap H between the first main electrode 160 and the first semiconductor layer 130, and the second main electrode 171 and the second semiconductor layer 140 There is also a gap H between them. In other words, the gap H between the two sides of the micro light emitting diode structure 100 is also the starting and ending point of the cutting of each gap 190 (as shown by the dotted line in the second figure B). Thereby, each of the light emitting diode unit 120 is divided into the first semiconductor layer 130, the active layer 150, and the second semiconductor layer 140 of independent components by the gap 190, namely Each independent first semiconductor layer 130, active layer 150, and second semiconductor layer 140 can be controlled through the first electrode 160 and the second electrode 170, so as to achieve the purpose of independently controlling the light emission of the light emitting diode unit 120.

Continuing, please refer to Figures 3 and 4 at the same time. Figure 3 is a side view of the micro light emitting diode structure of the second embodiment of the present invention, and Figure 4 is the micro light emitting diode structure of the second embodiment of the present invention. Side view of the structure. As shown in the third and fourth figures, another miniature light-emitting diode structure 200 proposed in this embodiment includes: a substrate 210; a plurality of light-emitting diode units 220 (in this embodiment, two ) Formed on the substrate 210, and each light-emitting diode unit 220 includes: a first semiconductor layer 230; a second semiconductor layer 240 formed on the first semiconductor layer 230; an active layer 250 formed Between the first semiconductor layer 230 and the second semiconductor layer 240; and a plurality of gaps 290 are formed in each light emitting diode unit 220, and each gap 290 is connected to the A second semiconductor layer 240; a first electrode 270, arranged on the second semiconductor layer 240 of the first light-emitting diode unit 220 of the plurality of light-emitting diodes 220; at least one connecting electrode 280, arranged on the plurality of light-emitting diodes 220 Between two adjacent light-emitting diode units 220 in the diode unit 220, wherein one end of each connecting electrode 280 is disposed in the first semiconductor of one of the two adjacent light-emitting diode units 220 On the layer 230, the other end is disposed on the first semiconductor layer 230 of the other light-emitting diode unit of the two adjacent light-emitting diode units 220; and a tail electrode 260 is disposed on the plurality of light-emitting diodes On the second semiconductor layer 230 of the last light emitting diode unit in the body 220 unit.

Wherein, the first electrode 270, each connecting electrode 280, and the tail electrode 260 are all interdigitated electrode structures, and each includes a main electrode 271 and a plurality of sub-electrodes 273, and each light emitting diode unit 220 has a Each of the gaps 290 is between the plurality of adjacent sub-electrodes 273.

The difference between the structure of the micro-light-emitting diode 200 of this embodiment and the micro-light-emitting diode structure 100 of the first embodiment of the present invention (refer to the first A and the second A) is that the present embodiment The number of light-emitting diode units 220 is plural (the third and fourth figures only take two as an example), and the plurality of light-emitting diode units 220 are between two adjacent light-emitting diode units The connection electrode 280 is used for electrical connection. Specifically, in the embodiment shown in the third and fourth figures, sputtering is used to sputter a plurality of light-emitting diode units 220 on the second semiconductor layer 240 of the first light-emitting diode unit 220. A first electrode 270 is formed, and each sub-electrode 273 included in the first electrode 270 has only a partial area disposed on the second semiconductor layer 240 of the first light-emitting diode unit 220 (that is, the second semiconductor layer 240 has only a partial area). The area is in contact with each sub-electrode 273 of the first electrode 270); then, the first semiconductor layer 230 of one of the two adjacent light-emitting diode units 220 and the other light-emitting diode are also sputtered A connecting electrode 280 is formed on the first semiconductor layer 230 of the unit 220, and each sub-electrode 273 included in the connecting electrode 280 has only a partial area disposed on the first semiconductor layer 230 of the light emitting diode unit 220 (that is, two Only a part of the first semiconductor layer 230 of each light-emitting diode unit 220 is in contact with the sub-electrode 273 of the connection electrode 280); finally, sputtering is used in the plurality of light-emitting diode units 220, and the last one emits light A tail electrode 260 is formed on the second semiconductor layer 240 of the diode unit 220, and each sub-electrode 273 included in the tail electrode 260 has only a partial area disposed on the second semiconductor layer of the last light emitting diode unit 220 240 (that is, only a part of the second semiconductor layer 240 is in contact with each sub-electrode 273 of the tail electrode 260), by the configuration of the first electrode 270, each connecting electrode 280, and the tail electrode 260, each The light emitting diode units 220 are electrically connected to each other.

It is worth noting that, referring to the fourth figure, the interdigitated electrodes of the first electrode 270 and the tail electrode 260 in this embodiment have an "E"-shaped structure, and the interdigitated electrodes of each connecting electrode 280 appear similar. The "king"-shaped structure allows each sub-electrode on the connecting electrode to simultaneously contact the semiconductor layers of two adjacent light-emitting diode units.

The above structure is characterized in that there is a gap H between the 270 head electrode, each connecting electrode 280 and the main electrode 271 of the tail electrode 26 and the semiconductor layer. In other words, the gap H of the micro light emitting diode structure 200 is also The starting and ending points of the cutting of each gap 290 (as shown by the dashed line in the fourth figure). Thereby, each light-emitting diode unit is divided into the first semiconductor layer 230, the active layer 250, and the second semiconductor layer 240 of independent components by the gap 290; at the same time, each light-emitting diode unit 220 uses the first electrode 270. The arrangement of each connecting electrode 280 and the tail electrode 260 is electrically connected, and the first electrode 270 and the tail electrode 260 can be used to control the plurality of light-emitting diode units 220, each independent first semiconductor layer 230, The active layer 250 and the second semiconductor layer 240 achieve the purpose of independently controlling the light emission of the entire row of light emitting diode units 220.

In addition, the micro light emitting diode structure 220 of the second embodiment further includes at least one wire (not shown), and the at least one wire is erected on the substrate, and even connected to an external circuit outside the substrate. At least one wire can be electrically connected to the first electrode 270, the connecting electrode 280, and/or the tail electrode 260, so that the user can control the external circuit to independently control the connection with the first electrode 270, the connecting electrode 280 and/or the tail electrode. Each individual element contacted by the electrode 260 emits light. Wherein, the material of the aforementioned at least one wire and the first electrode 270, the connecting electrode 280 and the tail electrode 260 can be gold (Au), silver (Ag), copper (Cu), chromium (Cr), aluminum (Al), platinum ( Pt), nickel (Ni), titanium (Ti), tin (Sn) or their alloys and their laminate combinations.

Finally, please refer to Figures 5 and 6. Figure 5 is a side view of the micro light emitting diode structure of the third embodiment of the present invention, and Figure 6 is the micro light emitting diode structure of the third embodiment of the present invention Side view of the structure. As shown in the fifth and sixth figures, another miniature light-emitting diode structure 300 proposed in this embodiment includes: a substrate 310; a plurality of light-emitting diode units 320 (in this embodiment, two ), formed on the substrate 310, wherein each light emitting diode unit 320 includes: a first A semiconductor layer 330; a second semiconductor layer 340 formed on the first semiconductor layer 330; an active layer 350 formed between the first semiconductor layer 330 and the second semiconductor layer 340; and a plurality of gaps 390, It is formed in each light emitting diode 320 unit, and each gap 390 is connected to the second semiconductor layer 340 from the first semiconductor layer 330; a first electrode 370 is arranged in the plurality of light emitting diode units 320 On the second semiconductor layer 340 of the first light-emitting diode unit 320; at least one connecting electrode 380 is arranged between two adjacent light-emitting diode units 320 in the plurality of light-emitting diode units 320, wherein, One end of each connecting electrode 380 is arranged on the first semiconductor layer 330 of one of the two adjacent light emitting diode units 320, and the other end is arranged on the other of the two adjacent light emitting diode units 320 On the second semiconductor layer 340 of the light emitting diode unit 320; and a tail electrode 360 disposed on the first semiconductor layer 330 of the last light emitting diode unit 320 of the plurality of light emitting diode units 320.

Wherein, the first electrode 370, each connecting electrode 380 and the tail electrode 360 are all interdigitated electrode structures, and each includes a main electrode 371 and a plurality of sub-electrodes 373, and each light emitting diode unit 320 is Each of the gaps 390 is between the plurality of adjacent sub-electrodes 373.

The difference between the micro light emitting diode structure 330 of this embodiment and the micro light emitting diode structure 200 of the second embodiment of the present invention (refer to the third and fourth figures) is that the connecting electrode 380 includes the sub-electrode 373 One side is in contact with the first semiconductor layer 330 of one of the two adjacent light-emitting diode units 320, and the other side of the sub-electrode 373 is in contact with the second semiconductor layer 340 of the other light-emitting diode unit 320 (that is, two The structure position of another light-emitting diode unit among adjacent light-emitting diode units 320 is different); and each sub-electrode 373 of the tail electrode 360 is the same as the first semiconductor layer 330 of the last light-emitting diode unit 320 The contact makes each light-emitting diode unit 320 electrically connect to each other through the arrangement of the first electrode 370, each connecting electrode 380, and the tail electrode 360.

Further refer to the seventh figure, which is a side view of the micro light emitting diode structure of the fourth embodiment of the present invention. As shown in FIG. 7, the micro light emitting diode structure of this embodiment is a vertical micro light emitting diode structure 100C, which includes a light emitting diode unit 120, at least one buffer layer 195, and at least one conductive adhesive layer 196 , A conductive substrate 115, at least one first electrode 160 and a second electrode 170; wherein, the light-emitting diode unit 120 can be composed of a first semiconductor layer 130, an active layer 150 and a second semiconductor layer 140, etc. The epitaxial growth in sequence. In detail, the at least one buffer layer 195 is plated on a part of the bottom surface of the second semiconductor layer 140 by electroplating or sputtering. The buffer layer 195 may be composed of a non-conducting material, and the non-conducting material can use photoresist, poly Polyimide, epoxy or dielectric; as for the at least one conductive adhesive layer 196 of this embodiment, it is adjacent to the at least one buffer layer 195, and the at least one conductive The adhesive layer 196 is made of an Anisotropic Conductive Film (ACF) structure; the conductive substrate 115 can be a Si-n type substrate, and can be doped with group V elements such as phosphorus (P) and arsenic (As) , Or Ge-n type substrate, GaAs-n type substrate, InP-n type substrate, GaP-n type substrate, etc., the thickness of which can be between 100 to 300 microns.

It is worth noting that each of the at least one first electrode 160 formed on a part of the surface of the light-emitting diode unit 120 may also have a gap 190 produced by laser cutting, and the gap 190 is along the A first semiconductor layer 130, an active layer 150, and a second semiconductor layer 140 of the light-emitting diode unit 120 are cut, so that at least one first electrode 160 and one second electrode 170 of this embodiment can be independently controlled. The light-emitting diode units 120 separated by gaps 190; furthermore, each gap 190 is even more aligned with the boundary of at least one conductive adhesive layer 196.

In addition, the present invention further proposes a manufacturing method of a micro light emitting diode structure. Please refer to FIG. 8, which is a flowchart of a manufacturing method of a micro light emitting diode structure according to a preferred embodiment of the present invention. As shown in Figure 8, the manufacturing method includes the following steps: (A) setting a substrate 110; (B) shape Form a first semiconductor layer 130 on the substrate; (C) form an active layer 1510 on the first semiconductor layer 130; (D) form a second semiconductor layer 140 on the active layer 150; (E) Shot cutting the first semiconductor layer 130, the active layer 150 and the second semiconductor layer 140 to form a plurality of gaps 190 connected from the first semiconductor layer 130 to the second semiconductor layer 140; (F) setting a An electrode 160 is on the first semiconductor layer 130, the first electrode 160 includes a first main electrode 161 and a plurality of first sub-electrodes 163; and (G) a second electrode 170 is disposed on the second semiconductor layer 140 Above, the second electrode 170 includes a second main electrode 171 and a plurality of second sub-electrodes 173, and each gap 190 is between the plurality of adjacent first sub-electrodes 163 and the plurality of second sub-electrodes Between 173.

Specifically, in step (A), the substrate 110 is not limited to a single material, but may also be a composite substrate composed of a plurality of different materials. For example, the substrate 110 may be two mutually bonded first A substrate and a second substrate (not shown). In this embodiment, the material of the substrate 110 is sapphire; and in other possible embodiments, the material of the substrate may also be but not limited to lithium aluminum oxide (LiAlO ₂ ), zinc oxide (zinc oxide) oxide, ZnO), gallium phosphide (GaP), glass (Glass), organic polymer sheet, aluminum nitride (AlN), gallium arsenide (GaAs), diamond (diamond), Quartz (quartz), silicon (Si), silicon carbide (SiC) or diamond like carbon (DLC); in addition, the material of the substrate can be but not limited to methyl methacrylate Ester (PMMA), polyethylene terephthalate (PET), polycarbonate (PC), polyimide (PI), polyethylene naphthalate (PEN), cyclic olefin copolymer ( COC) or polyamide (PA) and other flexible plastic materials and composite layer materials.

In steps (B) to (D), organic chemical vapor deposition (MOCVD), liquid phase epitaxial growth (LPE), vapor phase epitaxial growth (VPE), inkjet pixel printing, coating Or column In the printing method, the first semiconductor layer 130, the active layer 150, and the second semiconductor layer 140 in the light emitting diode unit 120 are sequentially disposed on the substrate 110, and the first semiconductor layer 130 and the second semiconductor layer 140 The flow of electric charges converts electrical energy into light energy to make the active layer 150 emit light.

In step (E), the laser cutting method is along the side of the first semiconductor layer 130 close to the first electrode 160 to the side of the second semiconductor layer 140 close to the second electrode 170, Cut the first semiconductor layer 130, the active layer 150, and the second semiconductor layer 140 to form a plurality of gaps 190 on the light emitting diode unit 120, and make the first semiconductor layer 130, the active layer 150, and the second semiconductor layer 140 become Multiple independent components. In fact, the cutting form, angle or pitch of the laser can be arbitrarily changed according to the user's needs, and the present invention is not limited.

In steps (F) and (G), the first electrode 160 and the second electrode 170 are horizontally arranged on the first semiconductor layer 130 and the second semiconductor layer 130 and the second electrode 170 through coating, printing, sputtering or laser. On the semiconductor layer 140. Furthermore, the arrangement of the first electrode 160 and the second electrode 170 is such that each of the first sub-electrodes 163 included in the first electrode 160 has only a partial area (approximately to the midpoint of the first sub-electrode 163). Position) is disposed on the first semiconductor layer 130 (that is, the first sub-electrode 160 has only a partial area in contact with the first semiconductor layer 130), and each second sub-electrode 173 included in the second electrode 170 also has only a part The area (approximately to the midpoint of the second sub-electrode 170) is disposed on the second semiconductor layer (that is, only a part of the second sub-electrode 173 is in contact with the second semiconductor layer 140). Wherein, the first electrode 160 and the second electrode 170 are interdigitated electrodes, and the arrangement of the first sub-electrode 163 and the second sub-electrode 173 is mutually symmetrical or staggered.

When the first electrode and the second electrode receive the current generated by the external circuit via the wire, the two electrodes uniformly diffuse the current to the first semiconductor layer and the second semiconductor layer through the interdigitated electrode structure, thereby making the active layer emit light . At the same time, through the multiple gaps formed by laser cutting, the first The one semiconductor layer, the active layer and the second semiconductor layer are divided into a plurality of independent elements, so that the external circuit can independently control the light emission of each independent element in contact with each first sub-electrode and each second sub-electrode to achieve cost The purpose of the embodiments of the invention.

However, the above are only preferred embodiments of the present invention, and should not be used to limit the scope of implementation of the present invention, that is, simple changes and modifications made according to the scope of the patent application and description of the present invention still belong to the present invention. Covered.

(A)-(G): steps

Claims (12)

A miniature light emitting diode structure, comprising: a substrate; a light emitting diode unit formed on the substrate, the light emitting diode unit comprising: a first semiconductor layer; a second semiconductor layer formed on the first semiconductor layer On a semiconductor layer; an active layer formed between the first semiconductor layer and the second semiconductor layer; and a plurality of gaps formed in the light emitting diode unit, and each gap is formed by the first semiconductor layer Connected to the second semiconductor layer; and a first electrode disposed on the first semiconductor layer, the first electrode including a first main electrode and a plurality of first sub-electrodes; a second electrode disposed on the first On the two semiconductor layers, the second electrode includes a second main electrode and a plurality of second sub-electrodes; and a wire, which is electrically connected to the first electrode and the second electrode, respectively; wherein, each gap is between Between the adjacent plurality of first sub-electrodes and the plurality of second sub-electrodes. The micro light-emitting diode structure according to claim 1, wherein the light-emitting diode unit further includes a third semiconductor layer formed between the second semiconductor layer and the active layer. The micro light emitting diode structure of claim 1, wherein the first electrode and the second electrode are both interdigitated electrodes. The micro light-emitting diode structure according to claim 3, wherein the plurality of first sub-electrodes are arranged in parallel with the first main electrode, and the plurality of second sub-electrodes are arranged in parallel with the second main electrode. A miniature light emitting diode structure includes: a substrate; a plurality of light emitting diode units formed on the substrate, wherein each light emitting diode unit includes: a first semiconductor layer; a second semiconductor layer, forming On the first semiconductor layer; an active layer formed between the first semiconductor layer and the second semiconductor layer; and a plurality of gaps formed in the light emitting diode unit, and each gap is formed by the first semiconductor layer A semiconductor layer is connected to the second semiconductor layer; a first electrode is arranged on the second semiconductor layer of the first light-emitting diode unit of the plurality of light-emitting diode units; at least one connecting electrode is arranged on the plurality of light-emitting diode units Between two adjacent light-emitting diode units in the diode unit, wherein one end of each connecting electrode is disposed on the first semiconductor layer of one of the two adjacent light-emitting diode units, and The other end is arranged on the first semiconductor layer or the second semiconductor layer of the other light-emitting diode unit of the two adjacent light-emitting diode units; and a tail electrode is arranged in the plurality of light-emitting diode units On the first semiconductor layer or the second semiconductor layer of the last light emitting diode unit; Wherein, the first electrode, each connecting electrode and the tail electrode respectively include a main electrode and a plurality of sub-electrodes; wherein, each of the gaps on each light-emitting diode unit is between the adjacent plurality of sub-electrodes between. The micro light-emitting diode structure according to claim 5, wherein each light-emitting diode unit further includes a third semiconductor layer formed between the second semiconductor layer and the active layer. The micro light emitting diode structure according to claim 5, wherein the first electrode, each connecting electrode and the tail electrode are all interdigitated electrodes. The micro light emitting diode structure according to claim 7, wherein the plurality of sub-electrodes are arranged parallel to each other. The micro light emitting diode structure according to claim 1, further comprising a wire electrically connected to the first electrode and the tail electrode. A method for manufacturing a micro light emitting diode structure includes: (A) setting a substrate; (B) forming a first semiconductor layer on the substrate; (C) forming an active layer on the first semiconductor layer; D) forming a second semiconductor layer on the active layer; (E) cutting the first semiconductor layer, the active layer and the second semiconductor layer with a laser to form a plurality of semiconductor layers connected to the first semiconductor layer The gap of the second semiconductor layer; (F) disposing a first electrode on the first semiconductor layer, the first electrode including a first main electrode and a plurality of first sub-electrodes; and (G) Disposing a second electrode on the second semiconductor layer, the second electrode including a second main electrode and a plurality of second sub-electrodes, and each gap is between the adjacent first sub-electrodes Between the electrode and the plurality of second sub-electrodes. The micro light emitting diode structure according to claim 10, wherein in step (E), the laser cutting method is along the side of the first semiconductor layer close to the first electrode to the second The semiconductor layer is cut close to the side of the second electrode. The micro light-emitting diode structure according to claim 10, wherein in steps (F) and (G), the first electrode and the second electrode are interdigitated electrodes, and the first sub-electrode and the second The two sub-electrodes are arranged symmetrically or staggered.

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