TWI627317B - Rod micro light-emitting diode and manufacturing method the same - Google Patents

Abstract

A columnar micro-light emitting diode includes a first transparent substrate, a gallium nitride layer, a plurality of masks, a second transparent substrate, and a plurality of metal electrodes. The gallium nitride layer is disposed on the first transparent substrate, and the plurality of masks are disposed on the gallium nitride layer, and the masks are spaced apart from each other with a gap therebetween. Passing trimethylgallium to the gallium nitride layer for a period of time, stopping the introduction of trimethylgallium, and then introducing ammonia gas into the gallium nitride layer for a period of time, stopping the introduction of ammonia gas, the above cycle is a growth cycle, gallium nitride The layer grows a plurality of gallium nitride pillars in each gap after a plurality of growth cycles, and then the plurality of metal electrodes are disposed under the second transparent substrate, the second transparent substrate adheres to the plurality of gallium nitride pillars, and the first transparent substrate and The second transparent substrate is transparent, and each of the gallium nitride pillars emits light thereon or below.

Description

Columnar micro-light emitting diode and manufacturing method thereof

The present invention relates to a light-emitting diode, and more particularly to a columnar micro-light emitting diode and a method thereof.

A light-emitting diode is a light-emitting semiconductor element that emits light of different colors because of its luminescent material. The red light materials used in the early stage of the indicator light, although there were also the development of blue light materials, were not commercialized because of the non-pure blue color or the luminosity of the light, until the Japanese scientists Amano and Akasaka Nakamura Shuji has jointly developed P-type gallium nitride and gallium nitride crystals, successfully producing pure blue and high-brightness light-emitting diodes, which has created a large number of popular blue-light diodes, and blue-light diodes are everywhere. Figure.

Nowadays, the use of blue light diodes with fluorescent powders is used to emit light of other colors. In addition, blue light diodes can also be used with two or more kinds of fluorescent powders to emit white light instead of the incandescent bulbs on the market. Due to the complexity of its manufacturing process, manufacturing costs have risen and failed to completely replace incandescent light bulbs. How to make the manufacturing process simple has become a problem to be solved.

In view of the above-mentioned problems, it is an object of the present invention to provide a columnar micro-light emitting diode and a method thereof for solving the problems faced by the prior art.

Based on the above object, the present invention provides a columnar micro-light emitting diode comprising a first transparent substrate, a gallium nitride (GaN) layer, a plurality of masks, a second transparent substrate, and a plurality of metal electrodes. The gallium nitride layer is disposed on the first transparent substrate, and then a plurality of masks are disposed on the gallium nitride layer, and the masks are spaced apart from each other with a gap therebetween. First into trimethyl gallium (of TMGa) in the gallium nitride layer over time, trimethylgallium into a first time period, stopping the flow of trimethyl gallium, ammonia gas and then (NH ₃₎ in a nitrogen During the gallium layer for a period of time, the time for introducing ammonia gas is the second time, the ammonia gas is stopped, and the first time is returned again. After the first time, the second time is combined, and the first time and the second time are combined into a growth cycle. The gallium nitride layer grows a plurality of gallium nitride pillars in each gap after a plurality of growth cycles, and the plurality of metal electrodes are disposed under the second transparent substrate, and the number of the plurality of metal electrodes corresponds to the number of the plurality of gallium nitride pillars Then, the second transparent substrate is adhered to a plurality of gallium nitride columns.

Preferably, each of the masks includes one of tantalum nitride (Si ₃ N ₄ ), hafnium oxide (SiO ₂ ), and aluminum oxide (Al ₂ O ₃ ).

Preferably, each metal electrode is corresponding and covers a plurality of gallium nitride columns.

Preferably, each of the metal electrodes is correspondingly disposed along a side of a cross section of the plurality of gallium nitride pillars.

Preferably, each of the metal electrodes includes one of silver (Ag), aluminum (Al), copper (Cu), titanium (Ti), nickel (Ni), and gold (Au).

Preferably, a plurality of fluorescent particles are disposed under the first transparent substrate.

Based on the above object, the present invention provides a method of manufacturing a columnar micro-light emitting diode, comprising: (1) providing a first transparent substrate, and growing nitrogen on the first transparent substrate by epitaxial growth The gallium layer (2) deposits a mask layer over the gallium nitride layer, and becomes a plurality of masks by exposure and development, and the masks are spaced apart from each other with a gap therebetween (3) passing through the trimethylgallium For a period of time, the gallium nitride layer is introduced into the trimethylgallium for the first time, the access to the trimethylgallium is stopped, and the ammonia gas is introduced into the gallium nitride layer for a period of time, and the ammonia gas is introduced for the second time. Time, stop the introduction of ammonia gas, return to the first time again, the second time after the first time, the first time and the second time are combined into a growth cycle, and the gallium nitride layer grows in each gap after multiple growth cycles A plurality of gallium nitride pillars (4) adhere the second transparent substrate to the plurality of gallium nitride pillars, and a plurality of metal electrodes are deposited on the second transparent substrate.

Preferably, the manner of epitaxial growth includes chemical vapor deposition (CVD), molecular beam epitaxy (MBE), and atomic layer deposition (ALD).

Based on the above object, the present invention provides a columnar micro-light emitting diode array comprising a plurality of columnar micro-light emitting diodes arranged in a matrix, each of the columnar micro-light emitting diodes comprising a first transparent substrate and nitriding a gallium layer, a plurality of masks, a second transparent substrate, and a plurality of metal electrodes. The gallium nitride layer is disposed on the first transparent substrate, and then a plurality of masks are disposed on the gallium nitride layer, and the masks are spaced apart from each other with a gap therebetween. First, the trimethylgallium is introduced into the gallium nitride layer for a period of time, and the time for introducing the trimethylgallium is the first time, the access to the trimethylgallium is stopped, and the ammonia gas is introduced into the gallium nitride layer for a period of time. The time of entering the ammonia gas is the second time, the ammonia gas is stopped, and the first time is returned again. After the first time is the second time, the first time and the second time are combined into a growth period, and the gallium nitride layer passes through a plurality of gallium nitride columns are grown in each gap, a plurality of metal electrodes are deposited under the second transparent substrate, and the second transparent substrate is adhered to the plurality of gallium nitride columns, and the number of the plurality of metal electrodes corresponds to the plurality of The number of gallium nitride columns.

Preferably, the columnar micro-light emitting diode is provided with a control circuit, and the control circuit is electrically connected to each of the columnar micro-light emitting diodes and controls the light emission thereof.

In view of the above, the columnar micro-light emitting diode of the present invention and method thereof can have one or more of the following advantages:

(1) The columnar micro-light-emitting diode of the present invention and a method thereof, when an electric current is applied in the present invention, each gallium nitride column emits light by electricity, and each of the gallium nitride columns is regarded as a light spot, and Since the first transparent substrate and the second transparent substrate are both transparent, each of the gallium nitride pillars emits light thereon or below.

(2) The columnar micro-light-emitting diode of the present invention and the method thereof, wherein the gallium nitride column is grown by alternately introducing a gas, and it is not necessary to etch into a gallium nitride column through complicated chemical compounding.

(3) The columnar micro-light-emitting diode of the present invention and the method thereof, wherein a plurality of columnar micro-light-emitting diodes are used to form a columnar micro-light-emitting diode array for use in a backlight module of a display.

10‧‧‧First transparent substrate

20‧‧‧GaN layer

21‧‧‧Large GaN

30‧‧‧mask layer

31‧‧‧ mask

32‧‧‧ long strips

40‧‧‧ growth cycle

41‧‧‧First time

42‧‧‧ second time

50‧‧‧GaN Gallium Column

60‧‧‧Second transparent substrate

70‧‧‧Metal electrodes

80‧‧‧Fluorescent particles

90‧‧‧Control circuit

100‧‧‧Control electrode

311‧‧‧ gap

321‧‧‧ Growth space

P‧‧‧ positive

N‧‧‧negative

Fig. 1 is a flow chart showing a first embodiment of a columnar micro-light-emitting diode of the present invention and a method therefor.

Fig. 2 is a structural view showing a first embodiment of a columnar micro-light-emitting diode of the present invention and a method therefor.

Fig. 3 is a cross-sectional view showing a second embodiment of the columnar micro-light-emitting diode of the present invention and a method therefor.

Fig. 4 is a structural view showing a second embodiment of the columnar micro-light-emitting diode of the present invention and a method thereof.

Fig. 5 is a flow chart showing a third embodiment of the columnar micro-light emitting diode of the present invention and a method therefor.

The advantages and features of the present invention, as well as the technical methods of the present invention, are described in more detail with reference to the exemplary embodiments and the accompanying drawings. The embodiments of the present invention are to be construed as being limited by the scope of the present invention, and the invention The scope of the patent application is defined.

As shown in FIG. 1 and FIG. 2, the flow chart of the first embodiment of the columnar micro-light-emitting diode of the present invention and the method thereof, and the columnar micro-light-emitting diode of the present invention and the method thereof A structural diagram of the first embodiment. In this embodiment, a method of fabricating the present invention is described, which includes: (1) providing a first transparent substrate 10, and growing a gallium nitride layer 20 on the first transparent substrate 10 by epitaxial growth (2) The deposition mask layer 30 is formed over the gallium nitride layer 20 by exposure and development into a plurality of masks 31. The masks 31 are spaced apart from each other with a gap 311 (3) therebetween to pass through the trimethyl gallium in the nitrogen. The gallium layer 20 is heated for a period of time, and the time for introducing the trimethylgallium is the first time 41, the introduction of the trimethylgallium is stopped, and the ammonia gas is introduced into the gallium nitride layer 20 for a period of time, and the ammonia gas is introduced for a period of time. At the second time 42, the ammonia gas is stopped, and the first time 41 is returned again. After the first time 41 is the second time 42, the first time 41 and the second time 42 are combined into the growth period 40, and the gallium nitride layer 20 After a plurality of growth cycles 40, a plurality of gallium nitride pillars 50 (4) are grown in each gap 311 to deposit a plurality of metal electrodes 70 under the second transparent substrate 60, and the second transparent substrate 60 is adhered to the plurality of gallium nitride pillars. 50. The number of the plurality of metal electrodes 70 corresponds to the number of the plurality of gallium nitride columns 50. Among them, the epitaxial growth method is one of organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), and atomic layer deposition (ALD), and is not limited to a certain epitaxial growth method.

Each of the masks 31 includes one of tantalum nitride (Si ₃ N ₄ ), cerium oxide (SiO ₂ ), and aluminum oxide (Al ₂ O ₃ ), and the mask 31 is a high transmittance material in the visible light band. can. Each of the metal electrodes 70 includes one of silver (Ag), aluminum (Al), copper (Cu), titanium (Ti), nickel (Ni), and gold (Au), and the metal electrode 70 is a metal having good conductivity. .

The present invention is fabricated according to the above method, and includes a first transparent substrate 10, a gallium nitride layer 20, a plurality of masks 31, a second transparent substrate 60, and a plurality of metal electrodes 70. The gallium nitride layer 20 is disposed on the first transparent substrate 10, and then a plurality of masks 31 are disposed on the gallium nitride layer 20, and the masks 31 are spaced apart from each other with a gap 311 therebetween. The gallium nitride layer 20 grows a plurality of gallium nitride pillars 50 in each gap 311 through a plurality of growth cycles 40, and a plurality of metal electrodes 70 are disposed under the second transparent substrate 60, and the number of the plurality of metal electrodes 70 corresponds to a plurality of The number of gallium nitride pillars 50, followed by the second transparent substrate 60 adhered to the plurality of gallium nitride pillars 50, and the plurality of metal electrodes 70 correspond to and cover a plurality of gallium nitride pillars 50, perpendicular to the masks 31. In the direction, a plurality of metal electrodes 70 are connected by a wire, a plurality of metal electrodes 70 are positive electrodes P, a gallium nitride layer 20 is a negative electrode N, and a current is applied to the positive electrode P and the negative electrode N, and the current is uniformly passed through the gallium nitride column 50. The gallium nitride column 50 is uniformly illuminated.

In addition, the gallium nitride pillar 50 is etched by yellow light exposure development. At this time, the gallium nitride pillar 50 and the substrate 10 are left without the gallium nitride pillar 50, and the control is set on the gallium nitride layer 20. The electrode 100 is disposed on the second transparent substrate 60. The control circuit 90 connects the metal electrodes 70 (positive electrode P) through the metal wires buried in the second transparent substrate 60, and the control circuit 90 can control the metal electrodes 70. The current can be independently illuminate a specific gallium nitride column 50 through the control of the control circuit 90 and the control electrode 100. This method can flexibly change the process wafer size in a single wafer according to the customization requirements, thereby avoiding the process. The defect causes loss of yield and solves the current dilemma of mass production of micro-light-emitting diodes.

Please refer to FIG. 3 and FIG. 4 , which are respectively a cross-sectional view of a columnar micro-light-emitting diode of the present invention and a second embodiment thereof, and a columnar micro-light-emitting diode of the present invention and a method thereof. second A structural diagram of an embodiment. In the present embodiment, the components of the same component symbols are similar in configuration to those described above, and the likes are not described herein again.

A plurality of fluorescent particles 80 are disposed under the first transparent substrate 10, and the fluorescent particles 80 have various colors, for example, red fluorescent particles 80 and green fluorescent particles 80, so that the present invention emits various colored lights, of course, The white light is mixed by the combination of the various fluorescent particles 80 and the blue light emitted by the gallium nitride column 50.

Furthermore, each of the metal electrodes 70 is correspondingly disposed along a side of a cross section of the plurality of gallium nitride pillars 50. In a direction perpendicular to the respective masks 31, the metal electrodes 70 are connected by a wire, each metal The electrode 70 is a positive electrode P, the gallium nitride layer 20 is a negative electrode N, and a current is applied to the positive electrode P and the negative electrode N. The metal electrode 70 does not block the light emitted from the gallium nitride 50 column, and therefore, the gallium nitride column 50 is thereon or The underlying illumination increases the advantages of the present invention.

By the way, a plurality of columnar micro-light-emitting diodes can be arranged in a matrix to form a columnar micro-light-emitting diode array, and the structure of each column-shaped micro-light-emitting diode is as shown in FIG. The structure of each of the columnar micro-light-emitting diodes is further provided with a control circuit 90. The control circuit 90 controls the brightness of each of the columnar micro-light-emitting diodes, and the phosphor particles 80 of various colors are disposed under the first transparent substrate 10, and the adjustment control circuit is transmitted through the adjustment control circuit. The current of 90 is excited to excite different colors of the fluorescent particles 80 to emit different color lights, and the columnar micro-light emitting diode array can be applied to the backlight module of the display panel.

Please refer to FIG. 5, which is a flow chart of a third embodiment of the columnar micro-light emitting diode of the present invention and a method thereof. This embodiment is a method for directly forming a columnar micro-light-emitting diode array by using the large-sized first transparent substrate 10, which is slightly different from the foregoing embodiment, and includes: (1) providing a first transparent substrate 10, and The epitaxially grown gallium nitride layer 20 is etched by inductively coupled plasma (ICP) etching to form a plurality of strips of gallium nitride 21 (2) over a plurality of strips of gallium nitride 21 Cover layer 30, followed by The mask layer 30 is etched in a manner of exposure and development, and the mask layer 30 is formed into a plurality of elongated masks 32. The elongated masks 32 are spaced apart from each other and have a growth space 321 (3). Then, as described above, The growth cycle of alternating trimethylgallium and ammonia gas is 40, and the gallium nitride column 50 is grown in the growth space 321 (4) Finally, the second transparent substrate 60 is adhered to the plurality of gallium nitride columns 50, and the plurality of metal electrodes 70 are disposed. On the second transparent substrate 60, each of the metal electrodes 70 is disposed corresponding to and along the side of the cross section of the plurality of gallium nitride pillars 50. In the direction perpendicular to the elongated strips 32, the metal electrodes 70 are respectively disposed. The two electrodes are connected by a wire, each metal electrode 70 is regarded as a positive electrode P, the gallium nitride layer 20 is a negative electrode N, and a current is applied to the positive electrode P and the negative electrode N, and the gallium nitride column 50 emits light thereon or below. The method is suitable for an epitaxial growth system with a large cavity, and can complete a large area of the columnar micro-light-emitting diode array at one time, which is more time-saving.

In summary, the columnar micro-light-emitting diode of the present invention and the method thereof, the gallium nitride pillar 50 is grown by alternately introducing a gas, and is not required to be etched into the gallium nitride pillar 50 via complicated chemical compounding, and further, When the current is applied in the present invention, each of the gallium nitride pillars 50 emits light by electricity, and each of the gallium nitride pillars 50 is a light spot, and since both the first transparent substrate 10 and the second transparent substrate 60 are transparent, Each of the gallium nitride pillars 50 emits light thereon or below. In addition, a plurality of columnar micro-light-emitting diodes are formed into a columnar micro-light-emitting diode array, and can be controlled by the use of the control circuit 90. The light energy emitted by the gallium column 50 excites the fluorescent particles 80 of different colors to emit different colors of light, and further, the large-area columnar micro-light emitting diode array can be fabricated, and the control circuit 90 and the control electrode 100 are matched. The specific gallium nitride column 50 can be independently illuminated. In summary, the columnar micro-light-emitting diode of the present invention and the method thereof have the advantages as described above, do not limit the direction in which the gallium nitride pillar 50 emits light, and manufacture a columnar micro-light-emitting diode array by a combination of methods. A backlight module that can be used in displays.

The above is intended to be illustrative only and not limiting. Any equivalent modifications or alterations to the spirit and scope of the invention are intended to be included in the scope of the appended claims.

Claims (9)

a columnar micro-light emitting diode comprising: a first transparent substrate as a growth substrate of the columnar micro-light-emitting diode; a gallium nitride (GaN) layer disposed on the first transparent substrate; a plurality of masks disposed on the gallium nitride layer, each of the masks being spaced apart from each other and having a gap therebetween; a second transparent substrate as a light guide plate of the columnar micro-light emitting diode; a metal electrode disposed under the second transparent substrate and connected by a wire; wherein the periodic wheel flows into the trimethylgallium (TMGa) and the ammonia gas (NH ₃ ), and the plurality of gaps grow in the gap a gallium nitride column, the number of the plurality of metal electrodes is corresponding to the number of the plurality of gallium nitride pillars, the second transparent substrate is adhered to the plurality of gallium nitride pillars, and then the plurality of nitrogens are etched by yellow light exposure development a gallium pillar, separating the plurality of gallium nitride pillars and the gallium nitride layer, disposing a control electrode on the gallium nitride layer, and providing a control circuit on the second transparent substrate to connect the respective Metal electrode. The columnar micro-light emitting diode according to claim 1, wherein each of the masks comprises tantalum nitride (Si ₃ N ₄ ), hafnium oxide (SiO ₂ ), and aluminum oxide (Al ₂ O ₃ ). One of them. The columnar micro-light emitting diode according to claim 1, wherein each of the metal electrodes corresponds to and covers the plurality of gallium nitride columns. The columnar micro-light emitting diode according to claim 1, wherein each of the metal electrodes is correspondingly disposed along a side of a cross section of the plurality of gallium nitride pillars. The columnar micro-light-emitting diode according to claim 1, wherein each of the metal electrodes comprises silver (Ag), aluminum (Al), copper (Cu), titanium (Ti), nickel (Ni), and gold. One of (Au). The columnar micro-light emitting diode according to claim 1, wherein a plurality of fluorescent particles are disposed under the first transparent substrate. A method for manufacturing a columnar micro-light-emitting diode, comprising: providing a first transparent substrate as a growth substrate of the columnar micro-light-emitting diode, and transmitting an epitaxial growth manner on the first transparent substrate Growing a gallium nitride layer; depositing a mask layer over the gallium nitride layer, forming a plurality of masks by exposure and development, each of the masks being spaced apart from each other with a gap therebetween; Into trimethylgallium (TMGa) and ammonia (NH ₃ ), a plurality of gallium nitride columns are grown in each of the gaps; a second transparent substrate is provided as a light guide plate of the columnar micro-light emitting diodes, and a plurality of deposition plates are deposited a metal electrode is under a second transparent substrate, and each of the metal electrodes is connected by a wire, and the second transparent substrate is adhered to the plurality of gallium nitride columns, and the number of the plurality of metal electrodes corresponds to a plurality of nitrogens The number of gallium pillars; and etching and etching the plurality of gallium nitride pillars by yellow light exposure, separating the plurality of gallium nitride pillars and the gallium nitride layer, and providing a control electrode on the gallium nitride layer, And setting a control circuit to the second Above the transparent substrate, the metal electrodes are connected. The method for manufacturing a columnar micro-light-emitting diode according to claim 7, wherein the epitaxial growth method is an organic chemical vapor deposition (MOCVD) method, molecular beam epitaxy (MBE), and an atomic layer. One of the accumulation (ALD). A columnar micro-light emitting diode array comprising: a plurality of columnar micro-light emitting diodes arranged in a matrix, each of the columnar micro-light emitting diodes comprising: a first transparent substrate as the column a growth substrate of the micro-light-emitting diode; a gallium nitride layer disposed on the first transparent substrate; a plurality of masks disposed on the gallium nitride layer, each of the masks being spaced apart from each other a second transparent substrate as a light guide plate of the columnar micro-light emitting diode; and a plurality of metal electrodes disposed under the second transparent substrate and connected by a wire; Periodically, the trimethylgallium (TMGa) and the ammonia (NH ₃ ) are flowed, and a plurality of gallium nitride columns are grown in each of the gaps, and the second transparent substrate is adhered to the plurality of gallium nitride pillars, and then passes through the yellow Photoexpanding and etching the plurality of gallium nitride pillars, separating the plurality of gallium nitride pillars and the gallium nitride layer, and disposing a control electrode on the gallium nitride layer, and on the second transparent substrate A control circuit is provided to connect the respective metal electrodes.