JP2003115613A - Image display device and method of fabricating the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate risk of erroneous operation by improving disadvantage due to formation an interlayer insulation film, effectively utilizing light emitting function and realizing higher brightness and low power consumption. SOLUTION: On the first substrate 11 where light emitting elements 14 and drive circuit 15 are allocated, the second substrate including a wiring layer where the bump 16 is formed to the predetermined location is stacked, and the bump is connected to an electrode 14a of the light emitting element and moreover to an electrode 15a of the drive circuit. Accordingly, the light emitting element and drive circuit may be connected to an external electrical signal without covering by an insulation film. The light emitting element and drive circuit are allocated so that the light emitting surface 14A of the light emitting element is in the opposite direction to the circuit forming surface of the drive circuit. Meanwhile, since the side wall of the wiring allocated at the light emitting surface side of the light sensing area is formed as a sloping surface or the drive circuit is allocated with a certain inclination, high brightness and low power consumption can be realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device in which a light emitting section and a drive circuit section are arranged on a substrate, and further to a manufacturing method thereof.

[0002]

2. Description of the Related Art When light emitting elements are arranged in a matrix and assembled into an image display device, conventionally, a substrate such as a liquid crystal display device (LCD: Liquid Crystal Display) or a plasma display panel (PDP: Plasma Display Panel) is used. It has been practiced to form the device directly on top or to arrange a single LED package such as a light emitting diode display (LED display). For example, in an image display device such as LCD and PDP,
Since the elements cannot be separated from each other, it is common practice to form the elements at intervals of the pixel pitch of the image display device from the beginning of the manufacturing process.

On the other hand, in the case of an LED display, L
The ED chip is taken out after dicing, individually connected to external electrodes by wire bonding or bump connection by flip chip, and packaged. In this case, the pixels are arranged at a pixel pitch as an image display device before or after packaging, and this pixel pitch is independent of the element pitch at the time of element formation.

LED (light emitting diode) which is a light emitting element
Is expensive, it is possible to reduce the cost of the image display device using LEDs by manufacturing many LED chips from one wafer. That is, the price of the image display device can be reduced by changing the conventional LED chip size of about 300 μm square to an LED chip of several tens μm square and connecting the LED chips to manufacture the image display device.

[0005]

When an LED display is constructed by arranging LED chips, the reduction of pixels becomes a problem in achieving high definition. For example, it is necessary to secure a space for electrical connection between the LED, the driving circuit unit, and an external electric signal, which hinders reduction of the size of the pixel.

For example, when manufacturing an LED display, first, a first wiring layer is formed on a substrate and an adhesive layer is formed to form a red LED chip, a green LED chip, and a blue LED.
A semiconductor device including a chip and a driving circuit is arranged.
Then, an insulating film is formed so as to cover them and have a film thickness of about 50 μm, and after the connection hole is opened, a second wiring layer is formed. At this time, for example, epoxy resin is used as the insulating film, laser processing is used as a method of opening the connection hole, and Al is used as the second wiring layer. An example of each forming condition and wiring pattern forming method will be illustrated below.

Epoxy resin: 150 μm thick, then 150
Bake connection hole opening for 30 minutes at ℃: Excimer laser processing (wavelength 248 nm, 4
00mJ) Wiring layer formation: sputtering method, Al film thickness 1 μm Wiring pattern formation: resist patterning method + H ₃ PO
₄ etching

FIG. 52 is a plan view showing an arrangement state of a conventional LED chip and a drive circuit section, and FIGS.
FIG. 7 is a schematic cross-sectional view showing a conventional wiring connection method. Fig. 53
As shown in FIG. 3, after forming the first wiring 202 on the substrate 201 and covering the first wiring layer 202 with the adhesive layer 203, the LED chip 204 and the semiconductor element on which the driving circuit is formed are mounted on the first wiring layer 202. The drive circuit devices 205 to be arranged are arranged. As shown in FIG. 52, the LED chip 204 includes a red LED chip 204a, a green LED chip 204b, and a blue LED chip 204c as one set, and each pixel together with a drive circuit device 205 for driving them. LE
After arranging the D chip 204 and the drive circuit device 205,
As shown in FIG. 54, the insulating film layer 206 is covered and the second wiring layer 207 is formed thereon. Second wiring layer 207 and L
The connection between the ED chip 104 and the drive circuit device 205 is made through the device-second wiring connection hole 208a, and the connection between the first wiring layer 202 and the second wiring layer 207 is made through the wiring interlayer connection hole 208b. Do it.

However, in the above method, the LED
Chip 204, drive circuit device 205, and first wiring layer 202
In order to obtain electrical continuity with the second wiring layer 2
It is necessary to carry out via the wiring interlayer connection hole 208.
It is necessary to secure a space for arranging b. As shown in FIG. 52, the space 209 for arranging the wiring interlayer connection hole 208b hinders the reduction of the pixel size.

Further, the area occupied by the LED chip and the drive circuit portion itself is also a problem in reducing the size of the pixel. For example,
Considering the arrangement in the LED display, a red LED device including a red LED per pixel on a substrate, a green LED device including a green LED, and a blue L including a blue LED.
ED devices, and further, semiconductor devices each having a circuit for adjusting brightness and color tone are arranged in a plane. A desired number of pixels thus formed are continuously arranged to form a display panel of a display. At this time, the size of the pixel is the sum of the areas of the respective devices, but in particular, the circuit by the current drive system has a limit to downsizing, which hinders high definition.

On the other hand, not limited to the above LED display,
In various displays, how to effectively utilize light emission is an important key for achieving high brightness and low power consumption of the display. For example, in the case of an LED display, as described above, applying an adhesive on the substrate,
A red LED device, a green LED device, a blue LED device, and a semiconductor device equipped with an LED drive circuit for controlling them are arranged. At this time, each LED device and the semiconductor device are arranged substantially horizontally. When the LED device, which is the light emitting unit, and the semiconductor device are arranged horizontally in this way, the light emission of each LED device does not have directivity, so the light emission spreads in a wide angle, and when viewed as a display, it goes to the front. There is a problem that the amount of light decreases. There is also a risk that the drive circuit of the semiconductor device may malfunction due to the light from the LED device.

As an improved example of various displays, for example, Japanese Unexamined Patent Publication No. 2001-109008 discloses an active matrix type liquid crystal display device in which the cross-sectional shape of wiring is triangular or the like to improve the aperture ratio. JP 2
Japanese Patent Laid-Open No. 000-251655 discloses a planar image forming apparatus such as a plasma display in which a wiring located in an airtight container has an arc-shaped cross-sectional shape to expand a viewing angle. However, none of the techniques described in these publications have the idea of positively directing light emission to the front, and the above problems have not been solved yet.

The present invention has been proposed in view of the above conventional circumstances, and provides an image display device capable of reducing the pixel size and realizing high definition, and a manufacturing method thereof. The purpose is to Another object of the present invention is to provide an image display device capable of increasing the area of a light emitting region when the pixel size is fixed and achieving high brightness, and a manufacturing method thereof. Further, it is an object of the present invention to provide an image display device capable of separating a drive circuit unit from a light emitting region of a light emitting element and improving stability of circuit operation, and a manufacturing method thereof. .

Still another object of the present invention is to provide an image display device capable of effectively utilizing the light emission of the light emitting portion and realizing high brightness and low power consumption, and a manufacturing method thereof. . Another object of the present invention is to provide an image display device capable of preventing a malfunction of a drive circuit and improving reliability, and a manufacturing method thereof.

[0015]

In order to achieve the above object, the image display device of the present invention has a light emitting portion and a drive circuit portion for controlling the light emitting portion arranged on a substrate on which a wiring layer is formed. The electrode of the light emitting portion and the wiring layer are connected to each other through a connection hole provided so as to penetrate the light emitting portion. Further, in the method for manufacturing an image display device of the present invention, after arranging the light emitting portion and the drive circuit portion controlling the light emitting portion on the substrate on which the wiring layer is formed, the connection hole is formed so as to penetrate the light emitting portion. However, by filling the connection hole with a conductive material, the electrode of the light emitting portion and the wiring layer are electrically connected.

In the above description, the drive circuit section may also be connected to the wiring layer through the connection hole provided so as to penetrate the drive circuit section. In any case, electrical connection between the wiring layer on the substrate and the wiring layers can be achieved directly through the connection holes provided in the light emitting section and the drive circuit section. Therefore, it is not necessary to secure a space for arranging the wiring interlayer connection hole, and the pixel can be downsized.

Further, the image display device of the present invention is characterized in that the light emitting section and the drive circuit section are arranged on the substrate, and the light emitting section and the drive circuit section have a laminated structure. Is. Furthermore, the method of manufacturing an image display device of the present invention is characterized in that the light emitting section and the drive circuit section are laminated and mounted on the substrate.

In the conventional arrangement, the pixel size is determined by the drive circuit area + light emitting area, but with the above configuration, the pixel size can be reduced to only the drive circuit area. Further, when the pixel size is fixed, it is possible to increase the area of the light emitting portion region, and for example, high brightness is realized. In addition, the pixel size is further reduced and the definition is improved by using the connection through the connection hole.

Further, in any of the above image display devices, the light emitting surface of the light emitting portion and the circuit forming surface of the drive circuit portion may be arranged so as to face opposite directions. By disposing the light emitting surface of the light emitting portion and the circuit forming surface of the drive circuit portion in directions opposite to each other, noise current generated in the circuit due to light emitted from the light emitting element is reduced.

On the other hand, in order to achieve the above-mentioned object of achieving high brightness and low power consumption, the image display device of the present invention comprises light receiving portions arranged on a substrate, and the light emitting surface of the light receiving portions. It is characterized in that the side wall of the wiring arranged on the side is an inclined surface. Further, in the method for manufacturing an image display device of the present invention, in the method for manufacturing an image display device in which the light receiving parts are arranged on the substrate and the wiring is formed on the light emitting surface side of the light receiving parts, the light-shielding film thickness is gradation. The resist is exposed using a mask, and the resist is developed to form a resist pattern having sidewalls as inclined surfaces, and the metal layer is etched using the resist pattern as a mask to form wiring with sidewalls as inclined surfaces. It is characterized by doing.

By making the side wall of the wiring arranged on the light emitting surface side of the light receiving portion an inclined surface, the light which has been wasted or scattered in an irrelevant direction is reflected by this inclined surface, and the light emitting direction of the display. Will be headed for. Therefore, the light from the light emitting portion is effectively used, and high brightness and low power consumption are realized. Further, a part of the viewing direction, which has been obstructed by the wiring, becomes effective, and the viewing angle is expanded.

Similarly, in order to achieve the above-mentioned object of achieving high brightness and low power consumption, in the image display device of the present invention, the light emitting section and the drive circuit section for controlling the light emitting section are arranged on the substrate. The drive circuit section is arranged so as to be inclined with respect to the light emitting section. The method of manufacturing an image display device of the present invention is the method of manufacturing an image display device in which a light emitting unit and a drive circuit unit for controlling the light emitting unit are arranged on a substrate, wherein the drive circuit unit is inclined with respect to the light emitting unit. It is characterized by being arranged.

By arranging the driving circuit section in an inclined manner, light which has been wasted or scattered in an irrelevant direction until now is reflected by the driving circuit section and travels in the light emitting direction of the display. Therefore, the light from the light emitting portion is effectively used, and high brightness and low power consumption are realized. Also,
In particular, if the circuit forming surface of the drive circuit unit is arranged so as to face the direction opposite to the light emitting surface of the light emitting unit, light from the light emitting unit will not be incident on the circuit forming surface of the drive circuit unit, and malfunction will be prevented. It

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION An image display device and a method of manufacturing the image display device to which the present invention is applied will be described below in detail with reference to the drawings.

1 to 5 show an example of a process for manufacturing an image display device to which the present invention is applied. In this example, as shown in FIG. 1, first, the first wiring layer 2 is patterned on the substrate 1 and the adhesive layer 3 is formed on the substrate 1, and then the LED device 4 and the drive circuit device 5 are arranged thereon. To do. In this example, the LED device 4 is configured to emit light upward in the drawing. Up to this point, the process is the same as that of the conventional example described above. However, the space for opening the wiring interlayer connection hole, which is required in the conventional example, is not provided.

The LED device 4 includes a light emitting diode (LE).
D) It may be a single unit or may be contained in a package. Alternatively, it may be molded into a chip component by molding with resin or the like. Drive circuit device 5
For example, a semiconductor element formed by forming a circuit on the surface of a semiconductor substrate (Si substrate) using a semiconductor circuit forming technique is used. The semiconductor element may be used as it is as a so-called bare chip, or may be used in a state of being housed in a package or being molded into a chip component by molding with resin or the like.

Next, as shown in FIG. 2, the electrode lead-out portions 2a of the first wiring layer 2 are formed at the positions corresponding to the electrodes 4a and 5a of the LED device 4 and the drive circuit device 5 in correspondence with the electrodes. The connection holes 6 and 7 are formed so as to be exposed. These connection holes 6 and 7 penetrate the LED device 4, the drive circuit device 5, and further the adhesive layer 3, and L
For the ED device 4 and the drive circuit device 5, for example, RI
It can be formed by the E method. The adhesive layer 3 is
The connection holes 6a and 6b can be formed by removing them by a laser processing method or the like.

Next, after an insulating film is formed on the entire surface by the CVD method or the like, anisotropic etching is performed to cover the inner wall surfaces of the connection holes 6a and 6b with the insulating film 7 as shown in FIG. The insulating film 7 is formed for the purpose of preventing accidental short circuit.

After forming the insulating film 7, as shown in FIG. 4, the conductive material 8 is formed so as to fill the connection holes 6a and 6b.
To form. For the conductive material 8, for example, SnPb, gold (A
u) and the like can be used. Specifically, the conductive material 8 is filled in the connection holes 6a and 6b by, for example, a selective plating method. At this time, the conductive material 8 exposed on the upper surfaces of the LED device 4 and the drive circuit unit 5 is the electrode 4a of the LED device 4 described above.
And the electrode 5a of the drive circuit device 5 are brought into contact with each other, so that the light emitting element of the LED device 4 and the drive circuit of the drive circuit device 5 are electrically connected to the first wiring layer 2.

Finally, as shown in FIG. 5, after the insulating film 9 is formed so as to cover the LED device 4 and the drive circuit device 5,
Connection holes 9a and 9b are formed in the insulating film 9 by a laser processing method.
Are opened to form the second wiring layer 10. The connection hole 9
a and 9b are the electrode 4b of the LED device 4 and the drive circuit device 5
Of the electrodes 4b, 5b
Through the connection holes 9a and 9b.
Will be electrically connected to.

The image display device manufactured as described above, as shown in FIG. 6, has a set of a red LED device 4a, a green LED device 4b, and a blue LED device 4c on a substrate 1, which are arranged in a matrix. And the LE of each pixel
Drive circuit device 5 for driving D device
ED device 4a, green LED device 4b, blue LED device 4
It is configured by arranging it close to c. here,
Extra area for forming connection holes for connecting wiring layers (area corresponding to space 109 in FIG. 44)
It is possible to make the pixels finer without requiring.

The above is a basic configuration example of the image display device and the manufacturing method thereof to which the present invention is applied. In the above configuration, the light emitting surface 4A of the LED device 4 and the circuit forming surface 5A of the drive circuit device 5 are formed. Are arranged in the same direction, the light emission of the LED device 4 may enter the circuit forming surface 5A of the drive circuit device 5, which may cause a noise current in the circuit. To avoid this, the LED device 4
The light emitting surface 4A and the circuit forming surface 5A of the drive circuit device 5 may be arranged so as to face opposite directions. Therefore, an example in which the light emitting surface 4A of the LED device 4 and the circuit forming surface 5A of the drive circuit device 5 are arranged so as to face opposite directions will be described next with reference to FIGS. 7 to 11.

As shown in FIG. 7, the steps up to the step of forming the first wiring layer 12 and the adhesive layer 13 on the substrate 11 and disposing the LED device 14 and the drive circuit device 15 are the same as in the previous example. . However, the LED device 14 is arranged so that the light emitting surface 14A faces upward in the drawing, and the drive circuit device 15 is arranged so that the circuit forming surface 15A faces downward in the drawing. And
The electrode 15 a of the drive circuit section 15 is connected to the first wiring layer 12 via the bump 16.

Next, as shown in FIG. 8, the connection holes 17a,
17b is formed. The connection holes 17a and 17b are formed by, for example, the RIE method for the LED device 14 and the drive circuit device 15 and removing the adhesive layer 13 by the laser processing method. Here, the connection hole 1
7a penetrates the LED device 14 and the adhesive layer 13, and is formed so that the electrode lead-out portion 12a of the first wiring layer 12 is exposed. The connection hole 17b is formed so as to penetrate the drive circuit device 15 and expose the electrode 15b.

Next, after an insulating film is formed on the entire surface by the CVD method or the like, anisotropic etching is performed to cover the inner wall surfaces of the connection holes 17a and 17b with the insulating film 18 as shown in FIG.
Cover with. After forming the insulating film 18, as shown in FIG. 10, a conductive material 19 is formed so as to fill the connection holes 17a and 17b. For the conductive material 19, for example, SnPb
Or gold (Au) can be used. Specifically, for example, the conductive material 19 is filled in the connection holes 17a and 17b by a selective plating method. At this time, the LED device 14
The conductive material 19 exposed on the upper surface of the LED device 14 contacts the electrode 14a of the LED device 14, and the light emitting element of the LED device 14 is electrically connected to the first wiring layer 12. Further, the conductive material 19 with which the connection hole 17b is filled functions as a back surface side electrode of the drive circuit device 15.

Finally, as shown in FIG. 11, the LED
After forming the insulating film 20 so as to cover the device 14 and the drive circuit device 15, the connection holes 20a and 20b are opened in the insulating film 20 by a laser processing method to form the second wiring layer 21.
The connection holes 20 a and 20 b are the electrodes 1 of the LED device 14.
4b and the electrode 15b of the drive circuit device 15 (conductive material 19 functioning as a back surface side electrode). These electrodes 14b and 15b are provided with connection holes 20a and 20b.
It will be electrically connected to the second wiring layer 21 through.

In this example, the light emitting surface 14A of the LED device 14 is
And the circuit forming surface 15A of the drive circuit device 15 are arranged so as to face in mutually opposite directions, and it is possible to avoid the influence of the light emission of the LED device 14. For example, L
The light emission of the ED device 14 is the circuit formation surface 1 of the drive circuit device 15.
5A can be suppressed, and the noise current generated in the circuit due to this can be reduced.

Next, by arranging the LED devices on the drive circuit device in an overlapping manner, the image display device capable of reducing the area for the LED devices and the manufacturing method thereof will be described with reference to FIGS. 12 to 14. explain.

First, as shown in FIG. 12, the first wiring layer 32 is patterned on the substrate 31, the first insulating film 33 is formed by coating, and then the drive circuit device 34 is arranged thereon.
Next, as shown in FIG. 13, connection holes 35a and 35b penetrating the drive circuit device 34 and the first insulating film 33 are formed. These connection holes 35a and 35b are provided in the drive circuit device 35.
Is formed by, for example, the RIE method, and the first insulating film 33 is formed by removing the first insulating film 33 by the laser processing method or the like. Here, the connection hole 35a connects the electrode 34a of the drive circuit device 34 and the first wiring layer 32, and the connection hole 35b.
Is an intermediate electrode 34 formed on the upper surface of the drive circuit device 34.
connected to c. The intermediate electrode 34c is provided to connect an electrode of the LED device described later and the first wiring layer 32. The connection holes 35a and 35b are formed within the area of the drive circuit device 34, and the electrodes 34a and the intermediate electrodes 34c are formed on the connection holes 35a and 35b, so that the size of the drive circuit device 34 is not exceeded. It is possible to connect the circuit of the drive circuit device 34 to an external electric signal.

Subsequently, after forming the second insulating film 36 and the second wiring layer 37, as shown in FIG. 14, the third insulating film 38 is formed and the LED device 39 is mounted on the third insulating film 38. And place the wiring. At this time, the LED device 39 and the drive circuit device 34 are arranged so as to overlap with each other, and the LED device 39 has a stacked structure such that the LED device 39 fits within the projected area of the drive circuit device 34.

Regarding the wiring, first, as shown in FIG. 13, a connection hole 36a is formed in the second insulating film 36, and the electrode 34b of the drive circuit device 34 and the second wiring layer 37 are connected. The connection between the LED device 39 and the second wiring layer 37 is as shown in FIG.
As shown in FIG. 3, the connection is performed through the connection hole 40 a that penetrates the LED device 39 and the third insulating film 38. That is, the connection hole 40a penetrating the LED device 39 and the third insulating film 38 is formed, and the conductive material filled in the connection hole is used as the LED device 3.
By connecting to the electrode 39a of No. 9 and the electrode lead-out portion of the second wiring layer 37, electrical connection between the electrode 39a and the electrode lead-out portion is achieved. The other electrode 39 of the LED device 39
b is the intermediate electrode 3 on the drive circuit device 34 via the connection hole 40b penetrating the third insulating film 38 and the second insulating film 36.
4c, and further connected to the first wiring layer 32 through the connection hole 35b.

In the image display device manufactured as described above, pixels can be formed without exceeding the area of the drive circuit device 34, and high definition can be achieved. Figure 15 shows
It shows the arrangement state of the drive circuit device 34 and the LED device 39 in this example. Red LED device 39a, green L
The ED device 39b and the blue LED device 39c are both within the area of the drive circuit device 34, and in the case of the arrangement shown in FIG. 6, the pixel size of the drive circuit region + light emitting region is In the example, the drive circuit area is reduced.

Even in the image display device having the above structure, the LE
The light emitting surface 39A of the D device 39 and the circuit forming surface 34A of the drive circuit device 34 are arranged so as to face in opposite directions, and L
It is possible to avoid the influence of the light emission of the ED device 39. An image display device having such a structure will be described with reference to FIGS.

In this example, after forming the first wiring layer 42 on the substrate 41, as shown in FIG. 16, the drive circuit device 43 is arranged so that the circuit forming surface 43A faces downward in the drawing, and solder balls are formed. Electrode 43 of drive circuit device 43 using
a and 43c are connected to the first wiring layer 42. Next, FIG.
As shown in FIG. 7, the first insulating film 45 is formed and the second wiring layer 46 is formed thereon. Electrode 43 of drive circuit device 43
b, 43c and the second wiring layer 46 are connected to each other through the connection hole 47.
a, 47b. The connection holes 47a and 47b are provided so as to penetrate the drive circuit device 43 and the first insulating film 45.

Then, as shown in FIG. 18, a second insulating film 48 is formed, and an LED device 49 is arranged thereon. At this time, the light emitting surface 49A of the LED device 49 is arranged so as to face upward in the drawing.

The LED device 49 and the second wiring layer 46 are connected to each other through a connection hole 50a penetrating the LED device 49 and the second insulating film 48, as shown in FIG. That is, the connection hole 50a penetrating the LED device 49 and the second insulating film 48 is formed, and the conductive material filled in the connection hole is connected to the electrode 49a of the LED device 4 and the electrode lead-out portion of the second wiring layer 46. As a result, electrical connection between the electrodes 49a and the electrode lead-out portion is achieved. The other electrode 49b of the LED device 49 is connected to the second wiring layer 46 on the drive circuit device 43 through the connection hole 50b penetrating the second insulating film 48 and the first insulating film 45, and further the connection hole 47b. , The electrodes 43c, and the solder balls 44 are connected to the first wiring layer 42.

Also in this example, the light emitting surface 49A of the LED device 49 and the circuit forming surface 43A of the drive circuit device 43 are arranged so as to face in opposite directions, and the LED device 4
It is possible to avoid the influence of the light emission of 9. For example, it is possible to suppress the light emission of the LED device 49 from entering the circuit forming surface 43A of the drive circuit device 43, and it is possible to reduce the noise current generated in the circuit due to this.

By the way, in the image display device of each of the above examples, the LED device is arranged at the uppermost portion, and the LED emits light upward in the drawing. At this time, the via hole contributes to the reflection of light, and the luminous efficiency is improved. About this
This will be described with reference to FIGS. 19 and 20.

As shown in detail in FIGS. 19 and 20, in the LED device arranged at the top, the LED is
Both the n-electrode 51a and the p-electrode 51b of the (light-emitting portion) 51 are via holes 5 formed so as to penetrate the insulating film 52.
The wirings 55 and 56 are electrically connected via the wirings 3 and 54. Here, the metal with which the via holes 53 and 54 are filled has a high reflectance and acts as a mirror surface. As a result, L
Light emitted in the lateral direction of the ED 51 is also reflected forward and is effectively used for image display. This structure will be described later in detail.

In the image display device described above, it is necessary to arrange the LED devices in a matrix, and one method for that purpose is, for example, a method of rearranging the LEDs, which are light emitting elements, by magnifying transfer. Therefore, next, a method of arranging elements by the two-step expansion transfer method will be described.

First, the basic structure of the element arranging method by the two-step expansion transfer method will be described. The element arranging method by the two-step expansion transfer method is a temporary holding member so that the elements formed on the first substrate with a high degree of integration are separated from the state in which the elements are arranged on the first substrate. Then, two-step enlargement transfer is performed in which the element held by the temporary holding member is further separated and transferred to the second substrate. Although the transfer is performed in two steps in this example, the transfer can be performed in three steps or in multiple steps depending on the degree of enlargement in which the elements are arranged apart from each other.

FIG. 21 is a diagram showing the basic steps of the two-step expansion transfer method. First, elements 62 such as light emitting elements are densely formed on the first substrate 60 shown in FIG. By forming the elements densely, the number of elements generated on each substrate can be increased, and the product cost can be reduced. The first substrate 60 is a substrate on which various elements can be formed, such as a semiconductor wafer, a glass substrate, a quartz glass substrate, a sapphire substrate, and a plastic substrate. Each element 62 is formed directly on the first substrate 60. Alternatively, it may be an array of those formed on another substrate.

Next, as shown in FIG. 21B, each element 62 is transferred from the first substrate 60 to the temporary holding member,
Each element 62 is held on this temporary holding member. At this time, the resin around the elements is simultaneously coated for each element 62. The resin coating around the element is formed in order to facilitate the formation of the electrode pad and the handling in the transfer process. Note that the adjacent elements 62 are finally separated on the temporary holding member by performing selective separation by, for example, transfer between a plurality of temporary holding members, and are arranged in a matrix as illustrated. . That is, the element 62 is x
The image is also transferred so as to widen the space between the elements in each direction, and is also transferred so as to widen the space between the elements in the y direction perpendicular to the x direction. The distance separated at this time is not particularly limited, and as an example, the distance can be set in consideration of the resin portion formation and the electrode pad formation in the subsequent process.

After the first transfer step as described above, as shown in FIG. 21C, the elements 62 existing on the temporary holding member 61 are separated from each other. Is formed. As will be described later, the electrode pad is formed after the second transfer step in which the final wiring is continued, so that the electrode pad is formed in a relatively large size so that wiring failure does not occur at that time. Note that FIG.
The electrode pad is not shown in FIG. A resin-formed chip 64 is formed by forming electrode pads on each element 62 solidified with the resin 63. The element 62 is located substantially in the center of the resin-formed chip 64 on a plane, but may be located at a position deviated to one side or a corner side.

Next, as shown in FIG. 21D, the second transfer step is performed. In this second transfer step, the elements 62 arranged in a matrix on the temporary holding member 61 are transferred onto the second substrate 65 so as to be further separated together with the resin forming chip 64. Also in the second transfer step, the adjacent element 6
2 are separated from each other with the resin forming chip 64 and are arranged in a matrix as shown in the drawing. That is, the elements 62 are transferred so as to widen the spaces between the elements in the x direction, but are also transferred so as to widen the spaces between the elements in the y direction perpendicular to the x direction. Assuming that the positions of the elements arranged in the second transfer step correspond to the pixels of the final product such as an image display device, approximately an integer multiple of the pitch between the original elements 62 is arranged in the second transfer step. It is the pitch of the elements 62. Here, when the enlargement ratio of the pitch separated from the first substrate 60 by the temporary holding member 61 is n and the expansion ratio of the pitch separated from the temporary holding member 61 by the second substrate 65 is m, it is a substantially integer multiple. The value E of is expressed by E = n × m.

Wiring is provided to each of the elements 62 separated from each other by the resin-formed chip 64 on the second substrate 65. This time,
Wiring is performed by using the electrode pad or the like previously formed while suppressing connection failure as much as possible. This wiring is, for example, the element 62.
Is a light emitting element such as a light emitting diode, a p electrode,
Including a wiring to the n-electrode, in the case of a liquid crystal control element, a selection signal line, a voltage line, a wiring such as an alignment electrode film and the like are included.

In the two-step enlargement transfer method shown in FIG. 21, the electrode pad can be formed by utilizing the separated space after the first transfer, and the wiring is provided after the second transfer. By using the electrode pads or the like previously formed, wiring is performed while suppressing connection failure as much as possible. Therefore,
The yield of the image display device can be improved. In addition, in the two-step magnifying transfer method of this example, the step of separating the distance between the elements is two steps. Will be reduced. That is, for example, here, the enlargement ratio of the pitch separated from the first substrate 60 by the temporary holding member 61 is 2 (n = 2), and the expansion of the pitch separated from the temporary holding member 61 by the second substrate 65 is performed. The rate is 2 (m =
If 2), if it is attempted to transfer to an expanded area by one transfer, the final expansion ratio is 4 times 2 × 2, and the squared transfer is performed 16 times, that is, alignment of the first substrate is performed 16 times. Although necessary, in the two-step enlargement transfer method of this example, the number of times of alignment is the enlargement ratio 2 in the first transfer step.
4 times the square of 2 and 4 times the square of the enlargement ratio 2 in the second transfer process are simply added, and a total of 8 times are required. That is,
If the same transfer magnification is intended, (n + m) ²
Since = n ² +2 nm + m ² , the number of times of transfer can be reduced by 2 nm. Therefore,
The manufacturing process also saves time and cost by the number of times, which is useful especially when the expansion rate is large.

In the second transfer step, the light emitting element is treated as a resin-formed chip and transferred from the temporary holding member to the second substrate. Refer to FIGS. 22 and 23 for this resin-formed chip. Explain. In each of the above examples, the resin-formed chips are arranged as an LED device. The resin-formed chip 64 is a device in which the elements 62 arranged apart from each other are hardened with a resin 63, and such a resin-formed chip 64 transfers the element 62 from the temporary holding member to the second substrate. It can be used in any case. The resin-formed chip 64 has a substantially flat plate shape and its main surface has a substantially square shape. This resin-formed chip 6
The shape of No. 4 is a shape formed by hardening the resin 63. Specifically, uncured resin is applied to the entire surface so as to include each element 62, and after hardening this, the edge portion is subjected to dicing or the like. It is a shape obtained by cutting.

Electrode pads 66 and 67 are formed on the front surface and the back surface of the substantially flat resin 63, respectively. The electrode pads 66, 67 are formed on the entire surface by electrode pads 66, 6
It is formed by forming a conductive layer such as a metal layer or a polycrystalline silicon layer which is the material of No. 7, and patterning it into a required electrode shape by a photolithography technique. These electrode pads 66 and 67 are formed so as to be respectively connected to the p electrode and the n electrode of the element 62 which is a light emitting element, and a via hole or the like is formed in the resin 63 when necessary.

Here, the electrode pads 66 and 67 are formed on the front surface side and the back surface side of the resin-formed chip 64, respectively, but it is also possible to form both electrode pads on one surface, for example, in the case of a thin film transistor. Since there are three electrodes of a source, a gate, and a drain, three or more electrode pads may be formed. Electrode pad 66,
The position of 67 is deviated on the flat plate so that the contacts do not overlap even if the contacts are taken from above when the final wiring is formed. The shape of the electrode pads 66, 67 is not limited to the square shape, and may be another shape.

By constructing such a resin-formed chip 64, the periphery of the element 62 is covered with the resin 63, and the electrode pads 66 and 67 can be accurately formed by flattening, and the electrode pad is formed in a wider area than the element 62. 66,67
Can be extended, and handling is facilitated when the transfer in the next second transfer step is advanced by the suction jig. As described below,
Because the final wiring is performed after the second transfer step,
By using the relatively large size electrode pads 66 and 67 for wiring, wiring failure can be prevented.

Next, FIG. 24 shows the structure of a light emitting element as an example of an element used in the two-step expansion transfer method of this example.
24A is a device cross-sectional view, and FIG. 24B is a plan view. This light emitting element is a GaN-based light emitting diode, for example, an element that is crystal-grown on a sapphire substrate. In such a GaN-based light emitting diode, laser ablation occurs due to laser irradiation through the substrate, and film peeling occurs at the interface between the sapphire substrate and the GaN-based growth layer due to the phenomenon of nitrogen vaporization of GaN. It has a feature that element isolation can be facilitated.

First, regarding the structure, a hexagonal pyramidal GaN layer 72 selectively grown is formed on a base growth layer 71 made of a GaN-based semiconductor layer. An insulating film (not shown) is present on the underlying growth layer 71, and the hexagonal pyramidal GaN layer 72 is MOCVD-formed in the opening of the insulating film.
It is formed by the method. The GaN layer 72 is a pyramid-type growth layer covered with the S plane (1-101 plane) when the main surface of the sapphire substrate used during growth is the C plane, and is a region doped with silicon. is there. This G
The inclined S surface portion of the aN layer 72 functions as a clad having a double hetero structure. An InGaN layer 73, which is an active layer, is formed so as to cover the inclined S-plane of the GaN layer 72, and a magnesium-doped GaN layer 74 is formed outside thereof.
Is formed. This magnesium-doped GaN layer 74
Also functions as a clad.

In such a light emitting diode, the p electrode 7
5 and the n-electrode 76 are formed. The p-electrode 75 is Ni / Pt formed on the magnesium-doped GaN layer 74.
/ Au or Ni (Pd) / Pt / Au. The n-electrode 76 is formed by vapor-depositing a metal material such as Ti / Al / Pt / Au at the opening of the insulating film (not shown). The base growth layer 71
When taking out the n-electrode from the back side of the
Need not be formed on the surface side of the underlying growth layer 71.

The GaN-based light emitting diode having such a structure is an element capable of emitting blue light, and can be peeled off from the sapphire substrate relatively easily by laser ablation, and a laser beam is selectively irradiated. As a result, selective peeling is realized. The GaN-based light emitting diode may have a structure in which an active layer is formed on a flat plate or in a strip shape, or may have a pyramidal structure in which a C plane is formed at an upper end portion. Further, it may be another nitride-based light emitting device, a compound semiconductor device, or the like.

Next, a specific method for manufacturing an image display device to which the light emitting element arranging method shown in FIG. 21 is applied will be described. As the light emitting element, the GaN-based light emitting diode shown in FIG. 24 is used. First, as shown in FIG. 25, a plurality of light emitting diodes 82 are densely formed on the main surface of the first substrate 81. The size of the light emitting diode 82 may be minute, and for example, may be about 20 μm on each side. As the constituent material of the first substrate 81, a material having a high transmittance with respect to the wavelength of the laser with which the light emitting diode 82 is irradiated, such as a sapphire substrate, is used. Although the p-electrode and the like are formed in the light-emitting diode 82, the final wiring is not yet formed, and the groove 82g for separating the elements is formed, so that the individual light-emitting diodes 82 can be separated. The groove 82g is formed by, for example, reactive ion etching.

Next, the light emitting diode 82 on the first substrate 81 is transferred onto the first temporary holding member 83. Here, as an example of the first temporary holding member 83, a glass substrate,
A quartz glass substrate, a plastic substrate, or the like can be used. In this example, the quartz glass substrate was used. Further, a peeling layer 84 that functions as a release layer is formed on the surface of the first temporary holding member 83. For the release layer 84, a fluorine coat, a silicone resin, a water-soluble adhesive (for example, polyvinyl alcohol: PVA), polyimide, or the like can be used, but polyimide is used here.

At the time of transfer, as shown in FIG. 25, as shown in FIG. 25, an adhesive (for example, an ultraviolet curable adhesive) 85 sufficient to cover the light emitting diode 82 is applied on the first substrate 81 and is supported by the light emitting diode 82. Thus, the first temporary holding member 83 is superposed. In this state, as shown in FIG. 26, the adhesive 85 is irradiated with ultraviolet rays (UV) from the back surface side of the first temporary holding member 83 to cure it. The first temporary holding member 83 is a quartz glass substrate, and the ultraviolet ray transmits the ultraviolet ray to quickly cure the adhesive 85.

After curing the adhesive 85, a laser is applied to the light emitting diode 82 as shown in FIG.
Then, the light emitting diode 82 is separated from the first substrate 81 by laser ablation. G
Since the aN-based light emitting diode 82 decomposes into metallic Ga and nitrogen at the interface with sapphire, it can be peeled off relatively easily. An excimer laser, a harmonic YAG laser, or the like is used as a laser for irradiation. By the peeling using the laser ablation, the light emitting diode 82 is separated at the interface of the first substrate 81 and is transferred in a state of being embedded in the adhesive 85 on the temporary holding member 83.

FIG. 28 shows a state in which the first substrate 81 has been removed by the above peeling. At this time, the GaN-based light-emitting diode is peeled off from the first substrate 81 made of a sapphire substrate with a laser, and Ga86 is deposited on the peeled surface, so it is necessary to etch this. Therefore, wet etching is performed using an aqueous solution of NaOH or dilute nitric acid, and as shown in FIG.
Remove a86. Further, as shown in FIG. 30, the surface is cleaned by oxygen plasma (O ₂ plasma), the adhesive 85 is cut by dicing to form a dicing groove 87, and each light emitting diode 82 is diced, and then the light emitting diode 82. Selective separation of. As the dicing process, dicing using a normal blade and laser processing using the above laser are performed when a narrow cut of 20 μm or less is required. The cut width depends on the size of the light emitting diode 82 covered with the adhesive 85 in the pixel of the image display device, but as an example, a groove is formed by an excimer laser to form a chip shape.

To selectively separate the light emitting diodes 82,
First, as shown in FIG. 31, a thermoplastic adhesive 88 is applied onto the cleaned light emitting diode 82, and a second temporary holding member 89 is placed thereon. As the second temporary holding member 89, a glass substrate, a quartz glass substrate, a plastic substrate, or the like can be used for the second temporary holding member 83, and the quartz glass substrate is used in this example. Further, a peeling layer 90 made of polyimide or the like is also formed on the surface of the second temporary holding member 89.

Then, as shown in FIG. 32, the laser is irradiated from the back surface side of the first temporary holding member 83 only to the position corresponding to the light emitting diode 82a to be transferred, and the light emitting diode 82a is subjected to laser ablation. The first
The temporary holding member 83 is peeled off. At the same time, visible or infrared laser light is irradiated from the back surface side of the second temporary holding member 89 to a position corresponding to the light emitting diode 82a which is also a transfer target, and the thermoplastic adhesive 88 in this portion is melted. And cure. Then, when the second temporary holding member 89 is peeled off from the first temporary holding member 83,
As shown in FIG. 33, only the light emitting diode 82a to be transferred is selectively separated and transferred onto the second temporary holding member 89.

After the selective separation, as shown in FIG. 34, a resin is applied to cover the transferred light emitting diode 82 to form a resin layer 91. Further, as shown in FIG. 35, the thickness of the resin layer 91 is reduced by oxygen plasma or the like.
As shown in FIG. 6, a via hole 92 is formed at a position corresponding to the light emitting diode 82 by laser irradiation. An excimer laser, a harmonic YAG laser, a carbon dioxide gas laser, or the like can be used to form the via hole 92. At this time, the via hole 92 has a diameter of, for example, about 3 to 7 μm.

Next, the anode side electrode pad 93 connected to the p electrode of the light emitting diode 82 through the via hole 92 is formed. The anode side electrode pad 93 is
For example, it is formed of Ni / Pt / Au or the like. FIG. 37 shows a state in which the light emitting diode 82 is transferred to the second temporary holding member 89, the via hole 92 on the anode electrode (p electrode) side is formed, and then the anode side electrode pad 93 is formed.

After forming the anode side electrode pad 93, the third side is formed to form the cathode side electrode on the opposite surface.
Is transferred to the temporary holding member 94. The third temporary holding member 94 is also made of, for example, quartz glass. At the time of transfer, as shown in FIG. 38, the light emitting diode 82 having the anode side electrode pad 93 formed thereon, and further the resin layer 9 are formed.
Adhesive 95 is applied on the surface 1 and the third temporary holding member 94 is attached thereon. In this state, when a laser is irradiated from the back surface side of the second temporary holding member 89, the second temporary holding member 89 made of quartz glass and the polyimide formed on the second temporary holding member 89 are used. Peeling by laser ablation occurs at the interface of the peeling layer 90
The light emitting diode 82 and the resin layer 91 formed on the peeling layer 90 are transferred onto the third temporary holding member 94. FIG. 39 shows a state in which the second temporary holding member 89 is separated.

When forming the cathode side electrode,
After the transfer process, O shown in FIG. _TwoBy plasma treatment
By removing the peeling layer 90 and the excess resin layer 91,
The contact semiconductor layer (n electrode) of the ion 82 is exposed.
Let The light emitting diode 82 is attached to the temporary holding member 94.
Held by the agent 95, the light emitting diode 82
The back surface of the is on the n-electrode side (cathode electrode side)
If the electrode pad 96 is formed as shown in FIG.
The pad 96 is electrically connected to the back surface of the light emitting diode 82.
Be done. Then, the electrode pad 96 is patterned. This
At this time, the electrode pad on the cathode side is, for example, about 60 μm.
It can be a corner. A transparent electrode is used as the electrode pad 96.
Electrode (ITO, ZnO type, etc.) or Ti / Al / Pt
A material such as / Au is used. Light emitting die for transparent electrodes
Even if the back side of the ode 82 is largely covered, the light emission is blocked.
Since there is no patterning, the patterning accuracy is rough and large electrodes are formed.
This facilitates the patterning process. In addition, above
When the electrode pad 96 is formed, the anod previously formed is formed.
The lead-out electrode 93a connected to the battery-side electrode pad 93.
If it is formed, the bump connection described later is very easy.
It will be The lead electrode 93a is formed of the resin layer
Via 91a is formed in 91, and the electrode pad 96 is formed.
Easy to form by patterning at the same time
You can

Next, the light emitting diodes 82 solidified by the resin layer 91 and the adhesive 95 are individually cut out to obtain the resin-formed chip. The cutting may be performed by laser dicing, for example. FIG. 42 shows a cutting process by laser dicing. Laser dicing is performed by irradiating a line beam of a laser, and the resin layer 91 and the adhesive 95 are cut until the third temporary holding member 94 is exposed. By this laser dicing, each light emitting diode 82 is cut out as a resin-formed chip of a predetermined size, and the LED device is transferred to a mounting step.

In the mounting process, the light emitting diode 82 (resin-formed chip) is separated from the third temporary holding member 94 by a combination of mechanical means (element suction by vacuum suction) and laser ablation. FIG. 43 is a view showing that the light emitting diodes 82 arranged on the third temporary holding member 94 are picked up by the suction device 97. At this time, the suction holes 98 are opened in a matrix at the pixel pitch of the image display device, and a large number of the light emitting diodes 82 can be sucked together. The opening diameter at this time is, for example, about 100 μm in diameter, and the openings are formed in a matrix shape with a pitch of 600 μm, and about 300 pieces can be adsorbed at once. The member of the adsorption hole 98 at this time is, for example, Ni.
Those produced by electroforming or stainless steel (SU
A metal plate such as S) is used by etching, and a suction chamber 99 is formed inside the suction hole 98. By controlling the suction chamber 99 to a negative pressure, the light emitting diode 82 is sucked. Will be possible. The light emitting diode 82 is covered with the resin layer 91 at this stage, and the upper surface thereof is substantially flattened. Therefore, selective adsorption by the adsorption device 97 can be easily promoted.

At the time of peeling the light emitting diode 82, the element suction by the suction device 97 and the peeling of the resin-formed chip by laser ablation are combined so that the peeling proceeds smoothly. Laser ablation is performed by irradiating a laser from the back surface side of the third temporary holding member 94. This laser ablation causes peeling at the interface between the third temporary holding member 94 and the adhesive 95.

In the method of arranging the light emitting elements as described above, the distance between the elements is already increased when the light emitting diodes are held by the temporary holding member, and the relatively large size is utilized by utilizing the widened distance. It is possible to provide an electrode pad or the like. Since wiring is performed using the electrode pads having a relatively large size, wiring can be easily formed even when the final device size is significantly larger than the element size. Further, in the light emitting element arranging method of the present example, the periphery of the light emitting diode is covered with the cured resin layer, the electrode pad can be accurately formed by flattening, and the electrode pad can be extended in a wider area than the element. When the transfer in the second transfer step of (1) is advanced by the suction jig, the handling becomes easy.

Next, an example of the structure of the image display device which is effective for realizing high brightness and low power consumption of the display and preventing malfunction will be described.

44 and 45 show an example of such an image display device. This image display device is shown in FIG.
As shown in FIG. 45, the red LED device 103, the green LED device 104, and the blue LED device 105 are arranged in a matrix on the substrate 101 on which the adhesive layer 102 is formed. A horizontal first wiring layer 106 is formed on the substrate 101, and a second wiring layer is formed in a direction orthogonal to the first wiring layer 106 via an insulating layer 107. The second wiring layer is composed of wiring 108 continuous in the vertical direction and strip-shaped wiring 109, and the wiring 108 continuous in the vertical direction is provided on one of the electrode pads 103a, 104a of the LED devices 103, 104, 105. , 105
Further, a strip-shaped wiring 109 is formed so as to connect to the other electrode pad 103b, 104b, 105b and the first wiring layer 106 via the connection hole 110.

The feature of this example is that the LED devices 103, 104, 105 of the wirings 108, 109 arranged on the light emitting surface side of the LED devices 103, 104, 105 are arranged.
That is, the side walls 108a and 109a facing each other are inclined surfaces. In this example, each of the wirings 108 and 109 has a triangular cross section, and each of the LED devices 103 and 10 is
Sidewalls 108a and 109a facing 4,105 are inclined surfaces. Side walls 108a of the wirings 108 and 109,
By forming the inclined surface 109a, the light emitting element 103
Of the light emitted from the c, 104c, and 105c, the light that has been wasted or scattered in an irrelevant direction is the inclined surfaces 108a and 109a as shown in FIG.
It is reflected by and goes in the light emitting direction of the display. As a result, the light emitting elements 103c, 104c, 105c
Light is effectively used for display, and high brightness and low power consumption are realized. Also, the viewing angle is expanded. In particular,
For example, compared with the viewing angle (indicated by a broken line in the figure) when the wirings 108 and 109 are normal wirings whose sidewalls are substantially vertical,
It is enlarged as shown by the solid line.

The wirings 108 and 109 having the above-mentioned triangular cross section.
Can be easily formed by patterning the resist by gradationizing the light shielding band thickness of the mask. FIG. 46 shows the wiring 108, 1 having a triangular cross section.
10 shows a formation process of No. 09. At the time of formation, first, as shown in FIG. 46A, a metal film 112 to be a wiring layer is formed on a substrate 111, and a resist layer 113 is uniformly formed thereon by coating. Then, FIG. 46 (b)
As shown in, the resist layer 113 is exposed through the mask 114 and developed. At this time, the light shielding band thickness of the mask 114 is made to be a gradation so that the incident light gradually increases toward the end of the pattern. When the resist layer 113 is exposed using this mask 114,
The thickness of the resist layer 113 to be exposed becomes gradually thicker toward the end, and when this is developed, for example, in the case of a positive type resist, the thickness of the remaining pattern becomes gradually thinner toward the end. As a result, a resist pattern 115 having a triangular cross section as shown in FIG. 46 (c) is formed.
Using this resist pattern 115 as a mask, FIG.
When the metal layer 112 is etched under the condition that the etching rates of the resist and the metal are almost equal as shown in (d), a wiring 116 having a triangular cross section is formed as shown in FIG. 46 (e). . As an etching method, for example, reactive ion etching (RIE) or the like can be adopted.

In addition to the method using a so-called halftone mask as described above, it is also possible to use a technique of giving a distribution of film thickness by defocusing. Furthermore, it is also possible to form the inclined surface by utilizing wet etching which is isotropic etching. FIG. 47 shows
It shows a method of forming an inclined surface by using wet etching. When the inclined surface is formed by using wet etching, as shown in FIG.
A metal layer 122 is formed thereon, and a mask 123 larger than a desired pattern shape is formed thereon. Then, when wet etching proceeds, the etching proceeds isotropically around the opening 123a of the mask 123,
An arcuate inclined surface 122a is formed.

The shapes of the wirings 108 and 109 are not limited to the above-mentioned triangular shape, but may be any shape having an inclined surface, and for example, as shown in FIG. 48, a trapezoidal cross section can be used. This trapezoidal wiring can also be formed by the same method as the above triangular wiring. Wiring 1 like this
The cross-sectional shapes of 08 and 109 are trapezoidal, and the side walls 108a,
By forming the inclined surface 109a, the light emitting element 103
Of the light emitted from the c, 104c, and 105c, the light that has been wasted or scattered in an irrelevant direction so far is the inclined surfaces 108a and 109a as shown in FIG.
It is reflected by and goes in the light emitting direction of the display. As a result, the light emitting elements 103c, 104c, 105c
Light is effectively used for display, and high brightness and low power consumption are realized. Also, the viewing angle is expanded.

In each of the above examples, the shape of the wiring formed on the light receiving surface side is devised so that the light is directed in the light emitting direction of the display. However, the drive circuit section for controlling the light receiving section is arranged obliquely. It is also possible to direct the light in the light emission direction of the display by utilizing the reflection at the drive circuit section. Therefore, a configuration example of an image display device in which the drive circuit section is obliquely arranged will be described next.

FIG. 49 shows the arrangement state in this example. On the substrate 131, the red LED device 132,
The green LED device 133 and the blue LED device 134 form a set to form a pixel. The LED device 132,
A drive circuit unit 135 for controlling the 133 and 134 is arranged adjacent to each other. Each LED device 132, 133,
The central part of the LED 134 is LEDs 132a, 133a, 134.
a is provided, which selectively emits light in accordance with an image signal. The drive circuit section 135 is made of, for example, a semiconductor element, and has a drive circuit formed on one surface thereof as a circuit formation surface.

Usually, the LED devices 132, 133, 1
34 and the drive circuit unit 135 are formed on the flat surface of the substrate 131, and in this case, as shown in FIG.
The light emitted from 32a, 133a, and 134a is emitted in all directions. In this example, as shown in FIG.
Adhesive layer 136 for adhesively fixing the drive circuit unit 135
To form an inclined surface, and the drive circuit unit 1 is formed on the inclined surface.
LED device 132, 133, 13
It is arranged diagonally with respect to 4. At this time, the LED device 1
32, 133, and 134 are LEDs 132a, which are light emitting units,
133a and 134a face the upper surface, the drive circuit portion 135 is arranged such that the circuit forming surface 135a faces the lower surface, and the back surface 135b of the drive circuit portion 135 is mirror-finished. The adhesive layer 136 is formed on the mold 13 as shown in FIG. 51, for example.
7. It can be easily molded with 7, and an inclined surface can be formed.

In this example, the LEDs 132a, 133a,
When 134a is caused to emit light, the emitted light in the lateral direction is reflected in the upper surface direction by the back surface 135b of the drive circuit unit 135 which is mirror-finished. Therefore, the brightness on the display surface is significantly improved. Further, the light from the LEDs 132a, 133a, 134a is prevented from entering the circuit forming surface 135a of the drive circuit unit 135, and the risk of malfunction of the drive circuit unit 135 is avoided.

[0091]

As is apparent from the above description, in the image display device of the present invention, it is possible to reduce the pixels and realize a high-definition display. Further, when the pixel size is fixed, it is possible to widen the area of the light emitting region and realize high brightness. Further, in the image display device of the present invention, by disposing the light emitting surface of the light emitting element and the circuit forming surface of the drive circuit portion in directions opposite to each other, noise current generated in the circuit by light emitted from the light emitting element is reduced. It is also possible to do so.

According to the method of manufacturing an image display device of the present invention, the image display device having the above advantages can be manufactured by a simple method, which is advantageous in terms of productivity and manufacturing cost. Further, in the method for manufacturing an image display device of the present invention, if the light-emitting elements formed in a dense state, that is, with a high degree of integration and subjected to microfabrication, are rearranged so as to be spaced apart, a large-area image display can be achieved. It is possible to manufacture the device with high productivity.

Further, in the image display device and the manufacturing method thereof according to the present invention, the side wall of the wiring arranged on the light emitting surface side of the light receiving portion is inclined so that it is wasted until now or scattered in an irrelevant direction. It is possible to reflect the existing light on this inclined surface and direct it in the light emitting direction of the display. As a result, it is possible to effectively use the light from the light emitting unit, and it is possible to realize high brightness and low power consumption. At the same time, it is also possible to make a part of the view direction blocked by the wiring effective and to expand the view angle.

Further, in the image display device and the method of manufacturing the same of the present invention, by arranging the drive circuit portion so as to be inclined with respect to the light emitting portion, the light that has been wasted or scattered in an irrelevant direction can be eliminated. It is reflected by this drive circuit section,
It is possible to direct the display to the light emitting direction.
Therefore, the light from the light emitting portion can be effectively used,
It is possible to realize high brightness and low power consumption.
In particular, if the circuit forming surface of the drive circuit unit is arranged so as to face the direction opposite to the light emitting surface of the light emitting unit, light from the light emitting unit will not be incident on the circuit forming surface of the drive circuit unit, preventing malfunction. It is also possible.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a manufacturing process of an image display device and showing an arrangement process of an LED device and a drive circuit device.

FIG. 2 is a schematic cross-sectional view showing a connection hole forming step.

FIG. 3 is a schematic cross-sectional view showing a step of forming an insulating film which covers an inner wall surface of a connection hole.

FIG. 4 is a schematic cross-sectional view showing a conductive material filling step by a selective plating method.

FIG. 5 is a schematic cross-sectional view showing a second wiring layer forming step.

FIG. 6 is a schematic plan view showing an arrangement state of an LED device and a drive circuit device.

FIG. 7 shows another example of the manufacturing process of the image display device, and is a schematic cross-sectional view showing an arrangement process of the LED device and the drive circuit device.

FIG. 8 is a schematic cross-sectional view showing a connection hole forming step.

FIG. 9 is a schematic cross-sectional view showing a step of forming an insulating film which covers an inner wall surface of a connection hole.

FIG. 10 is a schematic cross-sectional view showing a conductive material filling step by a selective plating method.

FIG. 11 is a schematic cross-sectional view showing a second wiring layer forming step.

FIG. 12 is a schematic cross-sectional view showing still another example of the manufacturing process of the image display device, showing the mounting process of the drive circuit device.

FIG. 13 is a schematic cross-sectional view showing a second wiring layer forming step.

FIG. 14 is a schematic sectional view showing an LED device mounting step.

FIG. 15 is a schematic plan view showing an arrangement state of an LED device and a drive circuit device.

FIG. 16 is a schematic cross-sectional view showing still another example of the manufacturing process of the image display device, showing the mounting process of the drive circuit device.

FIG. 17 is a schematic cross-sectional view showing a second wiring layer forming step.

FIG. 18 is a schematic sectional view showing an LED device mounting step.

FIG. 19 is a schematic plan view showing an electrode structure near the light emitting portion.

FIG. 20 is a schematic cross-sectional view showing an electrode structure near the light emitting portion.

FIG. 21 is a schematic view showing a method of arranging elements.

FIG. 22 is a schematic perspective view of a resin-formed chip.

FIG. 23 is a schematic plan view of a resin-formed chip.

FIG. 24 is a diagram showing an example of a light emitting element, in which (a) is a sectional view and (b) is a plan view.

FIG. 25 is a schematic cross-sectional view showing the step of joining the first temporary holding member.

FIG. 26 is a schematic sectional view showing a UV adhesive curing step.

FIG. 27 is a schematic sectional view showing a laser ablation step.

FIG. 28 is a schematic cross-sectional view showing the step of separating the first substrate.

FIG. 29 is a schematic cross-sectional view showing a Ga removing step.

FIG. 30 is a schematic sectional view showing a step of forming an element isolation groove.

FIG. 31 is a schematic cross-sectional view showing a step of joining a second temporary holding member.

FIG. 32 is a schematic sectional view showing a selective laser ablation and UV exposure process.

FIG. 33 is a schematic cross-sectional view showing a step of selectively separating light emitting diodes.

FIG. 34 is a schematic cross-sectional view showing a step of filling with resin.

FIG. 35 is a schematic cross-sectional view showing a resin layer thickness reduction step.

FIG. 36 is a schematic cross-sectional view showing a via forming step.

FIG. 37 is a schematic cross-sectional view showing a step of forming an anode-side electrode pad.

FIG. 38 is a schematic sectional view showing a laser ablation step.

FIG. 39 is a schematic cross-sectional view showing a step of separating a second temporary holding member.

FIG. 40 is a schematic sectional view showing a contact semiconductor layer exposing step.

FIG. 41 is a schematic cross-sectional view showing the cathode-side electrode pad forming step.

FIG. 42 is a schematic sectional view showing a laser dicing process.

FIG. 43 is a schematic cross-sectional view showing a selective pick-up process by the suction device.

FIG. 44 is a schematic plan view showing an example of an arrangement state and a wiring formation state of the LED device and the drive circuit section.

FIG. 45 is a schematic cross-sectional view showing an example in which the wiring has a triangular cross-sectional shape.

FIG. 46 is a schematic cross-sectional view showing an example of a method of forming wiring having a triangular cross section, in which (a) is a resist forming step.
(B) shows an exposing step, (c) shows a developing step, (d) shows a metal layer etching step, and (e) shows a wiring formation state.

FIG. 47 is a schematic sectional view showing a method of forming an inclined surface by wet etching.

FIG. 48 is a schematic cross-sectional view showing an example in which the cross-sectional shape of the wiring is trapezoidal.

FIG. 49 is a schematic plan view showing an example of an array state of the LED device and the drive circuit section.

FIG. 50 is a schematic cross-sectional view showing a state where the drive circuit section is obliquely arranged.

FIG. 51 is a schematic view showing a method of forming an inclined surface on the adhesive layer.

FIG. 52 is a schematic plan view showing an example of an arrangement state of a conventional LED device and a drive circuit device.

FIG. 53 is a diagram showing a conventional wiring forming process, and LE
It is a schematic sectional drawing which shows the arrangement process of D device and a drive circuit device.

FIG. 54 is a schematic cross-sectional view showing the second wiring forming step.

[Explanation of symbols]

21 first substrate, 22 first wiring layer, 24 LED device, 25 drive circuit device, 26 second substrate, 27 second
Wiring layer, 28 bumps, 51 First substrate, 52 Light emitting diode, 53, 59, 64 Temporary holding member, 55
Adhesive, 71 Second substrate, 72, 82 Wiring layer, 81
Transparent substrate, 83 solder bumps, 108, 109 wiring,
108a, 109a Side wall, 135 Drive circuit section, 13
5a Circuit forming surface, 136 Adhesive layer, 137 Mold

Claims (51)

[Claims] 1. A light emitting section and a drive circuit section for controlling the light emitting section are arranged on a substrate on which a wiring layer is formed, and the light emitting section is provided through a connection hole provided so as to penetrate the light emitting section. An image display device, characterized in that the electrode of (4) is connected to the wiring layer. 2. The image display device according to claim 1, wherein the drive circuit section is connected to the wiring layer through a connection hole provided so as to penetrate the drive circuit section. 3. The light emitting section is characterized in that the light emitting element is made into a chip component with resin.
The image display device described. 4. The image display device according to claim 3, wherein the light emitting element is an LED. 5. The image display device according to claim 1, wherein the drive circuit section includes a semiconductor element having a circuit formed on a semiconductor substrate. 6. The image display device according to claim 5, wherein the light emitting surface of the light emitting portion and the circuit forming surface of the drive circuit portion are arranged so as to face opposite directions. 7. A light emitting part and a drive circuit part for controlling the light emitting part are arranged on a substrate on which a wiring layer is formed, and a connection hole is formed so as to penetrate the light emitting part, and a conductive material is formed in the connection hole. A method for manufacturing an image display device, characterized in that the electrode of the light emitting portion and the wiring layer are electrically connected to each other by filling. 8. A connection hole is formed so as to penetrate the drive circuit portion, and a conductive material is filled in the connection hole to electrically connect the electrode of the drive circuit portion and the wiring layer. The method for manufacturing an image display device according to claim 7. 9. The drive circuit section is a semiconductor element having a circuit formed on a semiconductor substrate, and the light emitting surface of the light emitting section and the circuit forming surface of the drive circuit section are arranged in opposite directions. 8. The method for manufacturing an image display device according to claim 7, wherein. 10. A first transfer step in which the light emitting elements are transferred so as to be separated from the arrayed state in the manufacturing process and held by the temporary holding member, and the light emitting elements held by the temporary holding member are provided. 8. The method for manufacturing an image display device according to claim 7, wherein the light emitting elements are arranged on the substrate to form a light emitting portion by a second transfer step of further transferring the light emitting elements onto the first substrate. 11. The method of manufacturing an image display device according to claim 10, further comprising a process of making the light emitting element into a chip component with a resin. 12. An image display device characterized in that a light emitting section and a drive circuit section for controlling the light emitting section are arranged on a substrate, and the light emitting section and the drive circuit section have a laminated structure. 13. The image display device according to claim 12, wherein a wiring layer is formed on the substrate, and the wiring layer has a multilayer structure of two or more layers. 14. A first wiring layer, a drive circuit section, and
14. The image display device according to claim 13, wherein the light emitting portion and the second wiring layer are laminated in this order. 15. A first wiring layer, a drive circuit section, and
The image display device according to claim 13, wherein the second wiring layer and the light emitting portion are laminated in this order. 16. The image display device according to claim 12, wherein the electrode of the light emitting portion and the wiring layer are connected to each other through a connection hole provided so as to penetrate the light emitting portion. 17. The image display device according to claim 12, wherein the drive circuit section is connected to the wiring layer through a connection hole provided so as to penetrate the drive circuit section. 18. The image display device according to claim 12, wherein in the light emitting section, a light emitting element is made into a chip component with resin. 19. The image display device according to claim 18, wherein the light emitting element is an LED. 20. The image display device according to claim 12, wherein the drive circuit section includes a semiconductor element having a circuit formed on a semiconductor substrate. 21. The image display device according to claim 20, wherein the light emitting surface of the light emitting portion and the circuit forming surface of the drive circuit portion are arranged so as to face opposite directions to each other. 22. A method of manufacturing an image display device, characterized in that a light emitting section and a drive circuit section for controlling the light emitting section are laminated and mounted on a substrate. 23. The method of manufacturing an image display device according to claim 22, wherein a wiring layer having a multilayer structure of two or more layers is formed on the substrate. 24. A first wiring layer, a drive circuit section, and
24. The method of manufacturing an image display device according to claim 23, wherein the light emitting portion and the second wiring layer are sequentially laminated. 25. A first wiring layer, a drive circuit section, and
24. The method of manufacturing an image display device according to claim 23, wherein the second wiring layer and the light emitting portion are sequentially laminated. 26. A connection hole is formed so as to penetrate through the light emitting portion, and the connection hole is filled with a conductive material to electrically connect the electrode of the light emitting portion and the wiring layer. The method for manufacturing an image display device according to claim 22. 27. A connection hole is formed so as to penetrate the drive circuit portion, and the connection hole is filled with a conductive material to electrically connect the electrode of the drive circuit portion and the wiring layer. 23. The method for manufacturing an image display device according to claim 22. 28. The driving circuit section is a semiconductor element having a circuit formed on a semiconductor substrate, and the light emitting surface of the light emitting section and the circuit forming surface of the driving circuit section are arranged in opposite directions. 23. The method for manufacturing an image display device according to claim 22, wherein: 29. A first transfer step of transferring the light emitting elements and holding the light emitting elements on the temporary holding member so that the light emitting elements are separated from the arrayed state in the manufacturing process, and the light emitting elements held by the temporary holding member. 23. The second transfer process of further separating and transferring to the first substrate, the light emitting elements are arranged on the substrate to form a light emitting portion.
A method for manufacturing the image display device described. 30. The method of manufacturing an image display device according to claim 29, further comprising a step of converting the light emitting element into a chip component with a resin. 31. An image display device characterized in that light receiving portions are arranged on a substrate, and side walls of wirings arranged on the light emitting surface side of the light receiving portions are inclined surfaces. 32. The image display device according to claim 31, wherein the wiring has a trapezoidal sectional shape. 33. The image display device according to claim 31, wherein the wiring has a triangular cross-sectional shape. 34. The image display device according to claim 31, wherein a side wall of the wiring has an arc shape. 35. The image display device according to claim 31, wherein the wiring is made of metal or alloy. 36. The image display device according to claim 31, wherein in the light emitting section, a light emitting element is made into a chip component with resin. 37. The image display device according to claim 36, wherein the light emitting element is an LED. 38. A method of manufacturing an image display device, wherein light receiving portions are arranged on a substrate and wiring is formed on a light emitting surface side of the light receiving portions, wherein the resist is exposed by using a mask having a gradation of a light shielding band thickness. An image display characterized by forming a resist pattern having a sloped side wall by developing the resist pattern, and etching the metal layer using the resist pattern as a mask to form a wiring having a sloped side wall Device manufacturing method. 39. The method of manufacturing an image display device according to claim 38, wherein the etching is performed under conditions such that the etching rates of the resist pattern and the metal layer are substantially equal to each other. 40. The method of manufacturing an image display device according to claim 39, wherein the etching is performed by a reactive ion etching method. 41. An image characterized in that a light emitting portion and a drive circuit portion for controlling the light emitting portion are arranged on a substrate, and the drive circuit portion is arranged so as to be inclined with respect to the light emitting portion. Display device. 42. The image display device according to claim 41, wherein the circuit formation surface of the drive circuit portion is arranged so as to face the same direction as the light emitting surface of the light emitting portion. 43. The image display device according to claim 41, wherein a circuit formation surface of the drive circuit portion is arranged so as to face a direction opposite to a light emitting surface of the light emitting portion. 44. The surface of the drive circuit portion opposite to the circuit formation surface is mirror-finished.
3. The image display device according to item 3. 45. The image display device according to claim 41, wherein the drive circuit section is arranged so as to incline downward when the image display device is installed substantially vertically. 46. The image display device according to claim 41, wherein in the light emitting section, the light emitting element is made into a chip component with resin. 47. The image display device according to claim 46, wherein the light emitting element is an LED. 48. A method of manufacturing an image display device in which a light emitting section and a drive circuit section for controlling the light emitting section are arranged on a substrate, wherein the drive circuit section is arranged to be inclined with respect to the light emitting section. Image display device manufacturing method. 49. The method of manufacturing an image display device according to claim 48, wherein an adhesive layer having an inclined surface is formed on the substrate, and the drive circuit unit is installed on the inclined surface. 50. Molding the adhesive layer using a mold,
50. The method for manufacturing an image display device according to claim 49, wherein the inclined surface is formed. 51. The method of manufacturing an image display device according to claim 49, wherein the drive circuit portion is bonded to the adhesive layer such that the circuit forming surface of the drive circuit portion faces the adhesive layer.