KR20210153410A - Micro chips module arranged matrix and Method thereof - Google Patents

Abstract

The matrix array microchip module of the present invention has a plurality of microchips arranged in a matrix, a molding member that has a first surface and a second surface opposite to the first surface, and is formed by integrally molding the plurality of microchips in a state in which respective bonding pads are positioned to be exposed on the first surface, and electrode pads for surface mounting uniformly arranged on the first surface of the molding member. In the present invention, microchips are arranged in a matrix on a jig in a sorter and molding the microchips, thereby being a trade-off between defective handling of some chips and shortening of manufacturing time. Therefore, it is possible to manufacture a low-cost LED lighting device.

Description

Matrix arrangement microchip module and manufacturing method thereof

The present invention relates to a matrix array microchip module and a method for manufacturing the same, and to a matrix array microchip module capable of reducing manufacturing cost by shortening a manufacturing operation time of the microchip module and a method for manufacturing the same.

A light emitting device, for example, a light emitting diode (LED), is a type of semiconductor device that converts electrical energy into light, and is spotlighted as a next-generation light source that replaces conventional fluorescent lamps and incandescent lamps.

Since the light emitting diode generates light by using the potential gap of a semiconductor device, it has a longer lifespan, faster response characteristics, and low power consumption compared to conventional light sources, and has eco-friendly features. Accordingly, many studies are being conducted to replace the existing light source with a light emitting diode, and the light emitting diode is widely used as a light source for lighting devices such as various indoor and outdoor lamps, liquid crystal displays, electric signs, street lights, and headlamps. have.

Recently, in the field of flexible displays, display technology development using micro LEDs in which the chip size of light emitting diodes is manufactured in micro units is being carried out.

Micro LEDs are generally referred to as mini LEDs having a die size of 100 μm in unidirectional and 200 μm in long direction, and micro LEDs having a die size of 10 to 100 μm, that is, a size of 100 μm or less. separated by In any case, both mini and micro LEDs are made in micro size, so they are flexible, easy to enlarge compared to OLED, have a higher product lifespan, consume less power, and have high illuminance, so they can be easily seen under strong light such as sunlight. In particular, in terms of power consumption, micro LED has a power saving effect of 5 to 10 times or more compared to OLED, and can mass-produce large displays of 100 inches or more.

Micro LEDs that are currently being researched and developed are only 30 micrometers in length, and are less than one-tenth the length and one-hundredth the area of the LED chips (about 300 μm) currently used in displays. Therefore, the disadvantage is that it is not easy to separate the chip on the wafer and it takes a long time for packaging (substrate attachment and electrode connection). In order to produce micro LEDs like existing LED chips, it is necessary to develop 100 times faster equipment or to add 100 equipment, even arithmetic. Therefore, the problem of cost increase due to the attachment of tens to millions of LED chips is a point to be resolved.

Among the methods of manufacturing a micro LED, a method of forming an LED layer on a sapphire substrate is the most common. On the other hand, the manufacturing process of packaging millions of small-sized micro LED chips through a test handler in a bonding equipment can arrange the microchips with high precision, but the process of picking up millions of microchips one by one and arranging them with high precision is expensive and precise. It is being pointed out that it is uneconomical because it requires equipment and a long process time. Therefore, there is a need for a precise transfer technology that transfers millions of small-sized micro-LED chips onto a flexible or flat substrate at a precise and high speed. So far, there is no company in the world that has developed and commercialized an inorganic GaN-based micro LED light source and transfer process.

Publication No. 10-2004-0009818 Publication No. 10-2013-0097034 Publication No. 10-2018-0092719 Publication No. 10-2018-0105803 Publication No. 10-2019-0017181 Publication No. 10-2020-0012761 Registered Patent 10-1873259 Registered Patent 10-1658446 US Patent 10,297,712

In order to solve the problems of the prior art, the present invention provides a matrix array microchip module capable of arranging sawed microchips in a matrix and molding them to perform tray-off of defective processing of some chips and shortening of manufacturing operation time, and manufacturing thereof to provide a way.

Another object of the present invention is to provide a matrix array microchip module capable of reducing manufacturing cost by simultaneously molding a microlens array or a deformation preventing member during molding, and a method for manufacturing the same.

Another object of the present invention is to provide a matrix array microchip module capable of providing a light emitting module of a lighting device with improved light efficiency and shortened manufacturing operation time by using a micro LED, and a method for manufacturing the same.

The matrix array microchip module of the present invention has a plurality of microchips arranged in a matrix, a first surface and a second surface opposite to the first surface, and each bonding pad is positioned to be exposed on the first surface. A molding member formed by integrally molding a plurality of microchips, and electrode pads for surface mounting uniformly arranged on the first surface of the molding member may be provided.

In the present invention, a micro lens array uniformly arranged on the second surface of the molding member or a deformation preventing member disposed between the micro lens arrays may be provided.

In the present invention, the molding member may include a fluorescent layer.

In the present invention, the surface mounting electrode pads face each other and include a fork-shaped first electrode pad and a second electrode pad having branches interposed with each other. The first electrode pad has a first root electrode portion extending in a horizontal direction and a plurality of second branch electrode portions extending in a vertical direction and connected to positive bonding pads of microchips arranged in a vertical direction, and the second electrode pad includes: It may have a second root electrode part extending in a horizontal direction and a plurality of second branch electrode parts extending in a vertical direction and connected to negative bonding pads of the microchips arranged in a vertical direction.

In addition, in the present invention, the electrode pads for surface mounting are provided with a fork-shaped first and second electrode pads facing each other and having branches interposed with each other, and the first electrode pads are vertically extended and vertically arranged microchips. a plurality of first branch electrode parts connected to the plus bonding pads of the plurality of first branch electrode parts overlapping an upper end of one end of the plurality of first branch electrode parts and extending in the horizontal direction, one end of the lower first branch electrode parts through a corresponding via; It has a first root electrode part in contact, and the second electrode pad extends in a vertical direction and includes a plurality of second branch electrode parts connected to negative bonding pads of the microchips arranged in the vertical direction, and a plurality of second branch electrode parts. One end of the second root electrode portion overlaps the upper portion and extends in the horizontal direction, and the second root electrode portion is in contact with the other end of the lower second branch electrode portions through a corresponding via.

The method for manufacturing a matrix array microchip module of the present invention comprises the steps of picking up a plurality of sawed microchips and arranging them on a matrix, injecting a molding solution into a molding mold to mold a molding member, The steps of uniformly forming surface mounting electrode pads on a surface, performing a defect test of the plurality of microchips through the formed surface mounting electrode pads, and processing defective microchips detected in the defect test step. to provide

In the present invention, it is preferable that a concave portion for molding a micro lens array or a protrusion for a deformation preventing member is formed on the surface of the molding die.

In the present invention, in the step of processing the defect, it is preferable to laser destroy or mask the defective microchip.

In the present invention, the electrode pads for surface mounting may be made of copper, nickel, palladium, silver, or an alloy thereof, and may be formed by plating or sputtering.

In the present invention, the molding member may be transparent silicone or epoxy.

As described above, in the present invention, by arranging sawed microchips in a matrix and molding them, a tray-off of defective handling of some chips and shortening of manufacturing operation time can be performed. Therefore, it is possible to manufacture a low-cost LED lighting device.

However, the effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned above will be clearly understood by those skilled in the art without departing from the spirit and scope of the present invention.

1 is a plan view of a preferred embodiment of a matrix array microchip module according to the present invention;
Figure 2 is a cross-sectional view taken along line AA of Figure 1;
3 is a plan view of another preferred embodiment of a matrix array microchip module according to the present invention;
4 is a plan view of another preferred embodiment of a matrix array microchip module according to the present invention;
5 is a flowchart of a preferred embodiment for explaining the manufacturing process of the matrix array microchip module according to the present invention.

With respect to the embodiments of the present invention disclosed in the text, specific structural or functional descriptions are only exemplified for the purpose of describing the embodiments of the present invention, and the embodiments of the present invention may be embodied in various forms and the text It should not be construed as being limited to the embodiments described in .

Since the present invention can have various changes and can have various forms, specific embodiments are illustrated in the drawings and described in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention. In describing each drawing, similar reference numerals are used for components.

When an element is referred to as being “connected” or “connected” to another element, it is understood that it may be directly connected or connected to the other element, but other elements may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle. Other expressions describing the relationship between elements, such as "between" and "immediately between" or "neighboring to" and "directly adjacent to", etc., should be interpreted similarly.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as "comprise" or "have" are intended to designate that the specified feature, number, step, action, component, part, or combination thereof exists, and is one or more It should be understood that this does not preclude the possibility of addition or existence of other features or numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, preferred embodiments of the present invention will be further described with reference to the accompanying drawings. The same reference numerals are used for the same components in the drawings, and repeated descriptions of the same components are omitted.

1 is a plan view of a preferred embodiment of a matrix array microchip module according to the present invention, and FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1 .

In order to help the understanding of the present invention, a 4*4 matrix arrangement will be described as an example. It is not limited to a 4*4 matrix and can be extended to an n*n matrix array.

Referring to the drawings, the matrix array microchip module 100 includes a molding member 120 formed by integrally molding a plurality of microchips 110 arranged in a 4*4 matrix. The microchips 110 are sorted in a sorter and arranged in a matrix. As shown, some microchips may be shifted or rotated vertically or horizontally when arranged. Microchips that are shifted or rotated severely enough to cause defects such as short circuits and disconnections may be rejected later.

Each of the microchips 110 is an LED light source having a micro-size, and may include, for example, a mini-LED having a die size of 100 μm in one direction, 200 μm in a longitudinal direction, or a micro LED having a die size of 10 to 100 μm. The microchips 110 selectively emit light in a wavelength band from ultraviolet to infrared. The microchips 110 may include an ultra violet (UV) LED chip, a green LED chip, a blue LED chip, or a red LED chip or an infrared LED chip. The microchips 110 may have a thickness of 10 μm or more, for example, in a range of 10 μm to 100 μm. The thickness of these microchips 110 may vary according to a horizontal type chip or a vertical type chip, and the embodiment may be a flip chip. The planar configuration of the microchips 110 may be a polygonal shape, for example, a regular square or rectangular shape, and a circle shape. The microchips 110 include a light emitting structure and an electrode layer, and the light emitting structure may include a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, and may selectively emit light in a wavelength range from ultraviolet to infrared. have. The light emitting structure may include a group III-V compound semiconductor and a group II-VI compound semiconductor.

The electrode layer, that is, the bonding pad 112 may be connected to the surface mounting electrode pad 130 .

The molding member 120 may be, for example, silicone or an epoxy molding compound, and has a second surface 124 opposite to the first surface 122 . The electrode pad 130 for surface mounting is uniformly disposed on the first surface 122 of the molding member 120 . A micro lens array 140 and a deformation preventing member 150 are formed on the second surface 124 of the molding member 120 . A fluorescent layer 160 may be included between the first surface 122 and the second surface 124 of the molding member 120 .

The fluorescent layer 160 absorbs some light emitted from the light emitting device die 114 and converts the wavelength into light having a different wavelength. The phosphor may include at least one of a yellow phosphor, a green phosphor, a blue phosphor, and a red phosphor, and for example, a nitride-based phosphor, an oxynitride-based phosphor, which are mainly activated by a lanthanoid-based element such as Eu, Ce, or the like. Eronic phosphors, alkaline earth halogen apatite phosphors mainly activated by elements of lanthanoids such as Eu, and transition metals such as Mn, alkaline earth metal borate halogen phosphors, alkaline earth metal aluminate phosphors, alkaline earth silicates, alkaline earths Organic sulfide, alkaline earth thiogallate, alkaline earth silicon nitride, germanate, or rare earth aluminate mainly activated by lanthanoid elements such as Ce, rare earth silicate or organic mainly activated by lanthanoid elements such as Eu and at least one selected from organic complexes. As a specific example, a phosphor may be used, but the present invention is not limited thereto. The light emitted from the fluorescent layer 160 and the light emitted from the microchip 110 may be mixed into white light. White light may have a color temperature, for example, within the range of 2000K to 15000K. The white light may have a color temperature of at least one of warm white, cool white, and neutral white.

As shown, it can be seen that the bonding pad of the microchip (indicated by the dotted circle) and the electrode pad for surface mounting are misaligned because the microchip picked up from the sorter has somewhat inferior positioning accuracy when placed in the molding die. If this level is severe, defects such as short circuit and disconnection may occur, and the microchip is treated as a defective chip because it cannot operate. However, when used as an illumination light source, even if a small number of microchips among a plurality of microchips are processed poorly, the overall amount of light is not significantly affected, so it is possible to commercialize it to reduce the manufacturing cost.

3 is a plan view of another preferred embodiment of the matrix array microchip module according to the present invention.

The microchip module 200 of another embodiment of FIG. 3 is different in that the shape of the electrode pad 230 for surface mounting is a fork shape compared to the electrode pad 130 of the above-described embodiment. The positive bonding pads of each microchip are simultaneously connected to the fork-shaped first electrode pad 232 , and the negative bonding pads are simultaneously connected to the fork-shaped second electrode pad 234 . The first electrode pad 232 includes a first root electrode portion 232a extending in a horizontal direction and a plurality of second branch electrode portions 232b extending in a vertical direction and connected to positive bonding pads of microchips arranged in the vertical direction. ) are included. The second electrode pad 234 includes a second root electrode portion 234a extending in a horizontal direction and a plurality of second branch electrode portions 234b extending in a vertical direction and connected to negative bonding pads of microchips arranged in the vertical direction. ) are included. The first and second root electrode portions 232a and 234a of the first and second electrode pads 232 and 234, respectively, can greatly expand the area of the electrode portion compared to the exemplary embodiment, so BGA or precision soldering is reliable. can improve In addition, as the area of the electrode portion increases, the heat dissipation area also increases. In addition, the first and second branch electrode portions 232b and 234b of the positive electrode pad 232 and the negative electrode pad 234 constitute a fork shape sandwiched between each other, so that repeated physical stress of contraction/expansion due to heat generation of the LED chip. have stability in

4 is a plan view of another preferred embodiment of the matrix array microchip module according to the present invention.

The shape of the surface mounting electrode pad 330 of the microchip module 300 of another embodiment of FIG. 4 is compared with the electrode pad 230 of the other embodiment described above, and the first and second root electrode parts 332a and 334a. ) and the first and second branch electrode parts 332b and 334b are not formed on the same layer but on different layers, and are connected to each other through vias or vertical contacts 332c and 334c. The plurality of first branch electrode portions 332b extend in a vertical direction, respectively, and are connected to positive bonding pads of the microchips arranged in the vertical direction. The first root electrode part 332a overlaps one end of the plurality of first branch electrode parts 332b and extends in the horizontal direction, and makes contact with one end of the lower first branch electrode parts 332b through a corresponding via. do. The plurality of second branch electrode portions 334b extend in a vertical direction, respectively, and are connected to positive bonding pads of the microchips arranged in the vertical direction. The second root electrode part 334a overlaps the upper portions of the other ends of the plurality of first branch electrode parts 334b and extends in the horizontal direction, and makes contact with the other ends of the lower second branch electrode parts 334b through corresponding vias. do.

The module 300 of another embodiment is advantageous in that it can reduce the module area compared to the module 200 of another embodiment.

5 is a flowchart of a preferred embodiment for explaining the manufacturing process of the matrix array microchip module according to the present invention.

Referring to FIG. 5 , a microchip such as an LED is manufactured in a wafer unit through a deposition process or the like. Thereafter, a base sheet 200 such as a blue sheet is attached to the lower surface of the wafer. The base sheet is made of a material having elasticity, and an adhesive material is applied on one side to which the wafer is attached. Thereafter, a cutting groove is formed in a chip unit on a wafer through laser processing or the like (that is, a groove is formed to a predetermined depth), and then, when a predetermined impact is applied to the wafer, the wafer is separated into a plurality of semiconductor chips. In this way, the microchips are attached to the base sheet 200 in a separated state, mounted on a holder, and then transferred to a sorter.

In the sorter, microchips having different grades according to electrical and optical properties are measured using an optical property measuring device, etc. to determine the grade and classify the microchips by grade.

The chip sorter includes a chuck 402 to which the base seat holder is coupled, a swing arm 404 and a receiving bin 406 . While the swing arm swings at a high speed, the microchip adhered to the base sheet 400 coupled to the chuck is picked up and stored in the storage bin 406 . In the present invention, the microchips picked up by the swing arm 404 are arranged in a matrix on a jig (which may include a blue tape, a plate, or a molding mold) (S102). Therefore, it is possible to arrange the microchips on a matrix at high speed.

When the microchips are arranged in a matrix in this way, a transparent silicone or epoxy solution is injected to form the microchips integrally (S104). A jig, for example, a molding die or a molding die 408 is formed with a micro lens array recess 408a and a protrusion 408b for a deformation preventing member on the inner surface as shown. Therefore, during the molding process, the micro lens array 140 and the deformation preventing member 150 may be simultaneously molded. The deformation preventing member 150 may be formed into various shapes, such as a V-shaped trench, a cylindrical groove, or a conical groove, depending on the shape of the protrusion 408b.

When the molding is completed in this way, the electrode pads 130 for surface mounting are formed at regular intervals on the first surface 122 that is the lower surface of the molding member 120 . Here, the electrode pad 130 is formed of copper, nickel, palladium, silver, or an alloy thereof by plating or sputtering (S106).

Then, it is transferred to the test equipment to test the electrical characteristics of the chip through the electrode pad 130 to check whether there is a defect (S108). A chip (indicated by a red circle in FIG. 3 ) 410 checked as a bad chip in the test step will be checked as a bad pad misalignment.

The detected defective chip 410 may be processed in a state in which it is electrically removed from the normal chips by laser destruction or a masking process (S110).

As described above, although described with reference to preferred embodiments of the present invention, those of ordinary skill in the art may vary the present invention within the scope without departing from the spirit and scope of the present invention described in the claims below. It will be understood that modifications and changes can be made to

100, 200, 300: microchip module
110, 210, 310: microchip
112: bonding pad
120: molding member
122: first side
124: second side
130, 230, 330: electrode pad for surface mounting
140, 240, 340: micro lens array
150, 250, 350: anti-deformation member
160: fluorescent layer
232, 332: first electrode pad
232a, 332a; root electrode
232b, 332b; branch electrode
234, 334: second electrode pad
234a, 334a; root electrode
234b, 334b; branch electrode
332c, 334c; via or vertical contact
400: base sheet
402 : chuck
404 : swing arm
406: storage bin
408: jig
408a: groove
408b: protrusion
410: bad chip

Claims (13)

A matrix array microchip module comprising:
a plurality of microchips arranged in a matrix;
a molding member having a first surface and a second surface opposite to the first surface, wherein the plurality of microchips are integrally molded with each bonding pad positioned to be exposed on the first surface; and
A matrix array microchip module having electrode pads for surface mounting uniformly arranged on the first surface of the molding member. The matrix array microchip module according to claim 1, further comprising a microlens array uniformly arranged on the second surface of the molding member. The matrix array microchip module according to claim 1, further comprising a deformation preventing member uniformly arranged on the second surface of the molding member. The matrix array microchip module according to claim 1, wherein the molding member includes a fluorescent layer. The method according to claim 1, wherein the surface mounting electrode pads face each other and include a fork-shaped first electrode pad and a second electrode pad having branches interposed with each other,
The first electrode pad has a root electrode portion extending in the horizontal direction and a plurality of branch electrode portions extending in the vertical direction and connected to the positive bonding pads of the microchips arranged in the vertical direction,
The second electrode pad is a matrix array microchip module having a root electrode part extending in a horizontal direction and a plurality of branch electrode parts extending in a vertical direction and connected to negative bonding pads of the microchips arranged in the vertical direction. The method according to claim 1, wherein the surface mounting electrode pads face each other and include a fork-shaped first electrode pad and a second electrode pad having branches interposed with each other,
The first electrode pad extends in a vertical direction and overlaps with a plurality of first branch electrode portions connected to positive bonding pads of the microchips arranged in the vertical direction, and one end of the plurality of first branch electrode portions overlaps in a horizontal direction. has a first root electrode part extending to and in contact with one end of the lower first branch electrode parts through a corresponding via;
The second electrode pad extends in a vertical direction and overlaps with a plurality of second branch electrode portions connected to negative bonding pads of the microchips arranged in the vertical direction, and one end of the plurality of second branch electrode portions overlaps in a horizontal direction. A matrix array microchip module having a second root electrode part extending to and in contact with the other ends of the lower second branch electrode parts through a corresponding via. A method for manufacturing a matrix array microchip module, the method comprising:
picking up each of the sawed microchips and arranging them on a matrix;
molding the microchips arranged on the matrix into a molding member;
uniformly forming electrode pads for surface mounting on the first surface of the molding member;
performing a defect test of the plurality of microchips through the formed surface mounting electrode pads; and
and disposing of the defective microchip detected in the failure test step as a failure. [Claim 8] The method of claim 7, wherein a concave portion for forming a micro lens array is formed on the surface of the forming mold in the forming step. The method according to claim 7, wherein a protrusion for a deformation preventing member is formed on the surface of the molding die in the forming step. The method of claim 7 , wherein the step of processing the defect includes laser destruction or masking of the defective microchip. The method of claim 7, wherein the electrode pads for surface mounting are made of copper, nickel, palladium, silver, or an alloy thereof. The method of claim 11 , wherein the surface mounting electrode pads are formed by plating or sputtering. The method of claim 7 , wherein the molding member is made of transparent silicon or epoxy.

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