JP3660848B2 - Display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is used in a display such as a computer or a television receiver, for example, and is a transmissive or reflective liquid crystal display device provided with a switching element such as a thin film transistor (hereinafter referred to as “TFT”) as an address element. Includes a gate line, a source line, and a switching element provided in the vicinity of the intersection of the gate line and the source line, the switching element including a gate electrode connected to the gate line, and the source line A liquid crystal display device having a source electrode connected to the drain electrode and a drain electrode connected to a pixel electrode for applying a voltage to the liquid crystal layer, and a repetitive pattern such as a large number of wirings, switching elements, and sensor parts. A semiconductor device having a plurality of film patterns and a display device other than liquid crystal (for example, DMD) , Various types of display devices including active elements and passive elements such as image sensors, or substrates mounted with components such as resistors, capacitors, semiconductor elements and integrated circuit circuits for driving and controlling the active elements and passive elements .
[0002]
[Prior art]
A TFT type liquid crystal display device will be described as an example.
FIG. 6 is a circuit diagram showing a general configuration of a transmissive liquid crystal display device including an active matrix substrate.
As shown in FIG. 6, an active matrix substrate 101 has a plurality of pixel electrodes 102 formed in a matrix shape, such as several tens of thousands to several hundred thousand or more, and the pixel electrodes 102 are switching elements. The TFT 103 is connected and provided.
A gate wiring 104 for supplying a scanning signal is connected to the gate electrode of the TFT 103, and the TFT 103 is driven and controlled by the gate signal input to the gate electrode. A source wiring 105 for supplying a display signal (data signal) is connected to the source electrode of the TFT 103, and a data (display) signal is input to the pixel electrode 102 via the TFT 103 when the TFT 103 is driven.
The gate wirings 104 and the source wirings 105 are provided so as to pass through the periphery of the pixel electrodes 102 arranged in a matrix and to be orthogonal to each other with an insulating film interposed therebetween.
Further, the drain electrode of the TFT 103 is connected to the pixel electrode 102 and the additional capacitor 106, and the counter electrode of the additional capacitor 106 is connected to the common wiring 107.
[0003]
FIG. 7 is a cross-sectional view of a TFT portion of an active matrix substrate in a conventional liquid crystal display device.
As shown in FIG. 7, a gate electrode 108 connected to the gate wiring 104 of FIG. 6 is formed on a transparent insulating substrate 107, and a gate insulating film 109 is formed covering the gate electrode 108.
Further thereon, a semiconductor layer 110 is formed so as to overlap with the gate electrode 108, and a channel protective layer 111 is formed on the central portion thereof.
An n + Si layer that covers both ends of the channel protective layer 111 and part of the semiconductor layer 110 and is divided on the channel protective layer 111 is formed as the source electrode 112a and the drain electrode 112b.
A metal layer 113a is formed of the same film as the source wiring 105 in FIG. 6 on the source electrode 112a which is one n + Si layer, and the drain electrode 112b is formed on the drain electrode 112b which is the other n + Si layer. A metal layer 113b that connects the pixel electrode 114 and the TFT 115 serving as a switching element and its peripheral structure are formed.
Further, an interlayer insulating film 116 is formed so as to cover the TFT 115, the gate wiring, and the source wiring.
[0004]
A transparent conductive film to be the pixel electrode 114 is formed on the interlayer insulating film 116, and this transparent conductive film is a metal connected to the drain electrode 112b of the TFT 111 through a contact hole 116a that penetrates the interlayer insulating film 116. It is connected to the layer 113b.
As described above, since the interlayer insulating film 116 is formed between the gate wiring and the source wiring and the transparent conductive film 114 serving as the pixel electrode 1, the pixel electrode 114 is overlapped with the gate wiring and the source wiring. be able to.
[0005]
Such a structure is disclosed in, for example, Japanese Patent Application Laid-Open No. 58-172585, thereby improving the aperture ratio of the liquid crystal display device and shielding the electric field caused by the gate wiring and the source wiring. Therefore, it is possible to suppress the disclination in which the alignment of the liquid crystal molecules is broken.
[0006]
As the insulating film 109 or the interlayer insulating film 116, an inorganic film such as silicon nitride (SiN) has been conventionally formed to a film thickness of about 300 to 500 nm by using a CVD method (plasma enhanced chemical vapor deposition).
The reason why a film thickness larger than this is not formed is that deposition takes time and production efficiency deteriorates, and the substrate is warped due to residual stress, and defects such as cracks increase.
Alternatively, only the interlayer insulating film 116 may form an organic film with a thickness of about 1 to 5 μm.
Alternatively, there may be a case where the aperture ratio is lowered but the interlayer insulation 116 is not formed.
That is, a gate wiring, a source wiring, a pixel electrode, and a TFT transistor are deposited on the entire surface of the substrate 101, and the entire surface of the substrate is exposed, the entire surface of the substrate is etched, and the process is performed. The TFT substrates shown in FIGS. 6 and 7 were collectively formed by repeating the above and laminating the patterns.
[0007]
[Problems to be solved by the invention]
In the case of the above-described liquid crystal display device, a relatively small area such as 0 to 2 semiconductor layers or conductive film layers, for example, a pixel area, and a relatively large area such as about 2 to 5 layers, such as a TFT element area, are repeatedly patterned. In other words, regions having different production tacts and different defect rates are formed on the same substrate at the same time and through the same process, and production is basically inefficient.
In addition, since some of the TFT elements are defective because they are collectively formed, the entire substrate is treated as defective, and the profitability is very poor.
In particular, the TFT element portion having a large number of laminations has a smaller pattern size than that of other regions and a large number of laminations, so that the frequency of occurrence of defects is relatively high.
In the case of FIG. 7, when the insulating film 109 or the interlayer insulating film 116 is formed on the TFT element 115 by CVD or sputtering using SiNx, SiO2, TaOx (Ta: tantalum) or the like. The formed insulating film 109 or interlayer insulating film 116 reflects irregularities due to the thickness of the base film. Cracks A and B are more likely to enter due to the effects of residual stress (larger substrates have more in-plane variations), such as multi-layer TFTs and uneven portions such as cross sections of source wiring and gate wiring. Etching liquid permeates and short-circuiting and disconnection defects are likely to occur, and the larger the substrate, the lower the defect rate due to increased variations in residual stress, temperature, etching liquid or impurity concentration distribution, etc. For this reason, it becomes necessary to strictly control the apparatus and conditions, and the processing time is increased, and a special apparatus improvement is required.
[0008]
On the other hand, in liquid crystal display devices and the like, the number of parts to be taken increases to improve overall production efficiency, and there is a movement to adopt increasingly larger board dimensions, but for example, the line does not rise at the speed as expected at the start of mass production However, there are many cases where profits are not sufficiently secured or goods cannot be delivered to users in a timely manner due to the balance of supply and demand.
[0009]
Or reliability may fall by the same factor.
[0010]
Or, if the manufacturing equipment becomes larger due to the larger substrate size and it is difficult to assemble and transport (the transportation means, route and time are limited), the whole factory becomes large, and it is difficult to secure the site, It becomes difficult to uniformly control the cleanliness of the inner line.
[0011]
In addition, the variation in the external dimensions of each device increases, making line design difficult.
[0012]
Therefore, these parts and devices have limitations in high-density mounting, thinning, miniaturization, and weight reduction.
[0013]
The object of the present invention is to produce various electronic components including those other than liquid crystal display devices and electronic components, particularly in electronic components such as liquid crystal display devices and semiconductor devices in which the dimensions of the original substrate for production are large. An object of the present invention is to provide an electronic component manufacturing method and an electronic component that improve production efficiency with reliability, reduce the size of the apparatus, and reduce the above-described problems.
[0014]
[Means for Solving the Problems]
From the viewpoint of production efficiency, it is also a problem to form TFTs on the entire surface at once by tilting to a large substrate.
[0015]
In view of this, there has been proposed means for forming only a TFT element portion having a large number of laminations, a large number of processes, and a low yield on another substrate, and transferring the TFT element to form a TFT substrate.
[0016]
In US Pat. No. 5,904,545, the TFT element is formed on a separate substrate, separated into individual elements (chips), and transferred (stacked) onto a substrate that has been cut out in advance (formed with a recess). A manufacturing method, structure and apparatus for completing a TFT substrate are disclosed.
[0017]
That is, as described in FIG. 1 and FIG. 2, a region to be the TFT element portion 7 is previously formed with a recess in the substrate and an electrode 8 for electrical connection is formed, and transferred to the recess to transfer the TFT. This is a method for completing a substrate.
[0018]
The transfer process is described in FIG.
[0019]
That is, this is a method in which TFT elements 5 and 8 are formed in a TFT element block formed in advance on a separate substrate, and the TFT block is transferred to a recess in which the electrode terminal 10 is formed in advance.
[0020]
However, in this method, when the TFT element block is transferred to the concave portion of the substrate, there is a possibility that the direction of the block at the time of insertion is inserted with the left and right or the front-back direction reversed.
[0021]
When inserted in different directions, the connection between terminals is different from the design, resulting in a malfunction of the TFT element.
[0022]
In other words, it is not a complete self-alignment structure that is always in the same direction as the design when inserted.
[0023]
In view of this, a structure and means capable of realizing complete self-alignment are proposed as the present invention.
[0024]
The present invention uses a spherical ball silicon instead of the trapezoidal element block like the USP described above, means that a TFT element is formed on the surface thereof, and means that a normal terminal connection can always be made when it is inserted into the recess of the substrate. (Complete self-alignment means) is supplied.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
[0026]
(Embodiment 1)
An embodiment according to the present invention will be described in detail with reference to FIGS. 4 and 5 below, taking a TFT type liquid crystal display device as an example.
[0027]
FIG. 4 is a completed view of a ball silicon TFT element block according to the present invention.
[0028]
A method of exposing and forming a TFT element pattern on the surface of a sphere such as ball silicon is disclosed in JP-A-11-121368.
That is, here, an optical system including a reflecting mirror having a reflecting surface whose inner surface is a spheroidal shape is used.
By disposing a light source at one focal point and a spherical substrate at the other focal point, it is disclosed that most of the spherical substrate surface can be exposed simultaneously.
Using this technique, the TFT element 12 is formed on the surface of the ball silicon 11 by repeating the thin film deposition and the entire exposure process.
The TFT creation process is the same as the thin film used in the conventional TFT element described in the explanation of FIG. 7 and the creation process described in the explanation of FIG.
After the TFT element is formed on the surface of the ball silicon by the process, the gate electrode terminal 13, the source electrode terminal 14, and the drain electrode terminal 15 having the function of the TFT element electrode are shown in the other hemispherical partial region of the ball silicon. As shown in FIG.
Further, the TFT portion 12 and each gate electrode terminal 13, source electrode terminal 14, and drain electrode terminal 15 are electrically connected through corresponding gate lead-out wiring 21, source lead-out wiring 22, and drain lead-out wiring 23. ing.
Each wiring is electrically insulated via an interlayer insulating film.
After forming the TFT element, an insulating film 16 is formed on the entire surface of the sphere as a protective film, exposed and etched to leave the protective insulating film 16 on the hemispherical region where the TFT element is formed, and the other hemisphere on the other terminal side The insulating film in the partial region is removed.
As a result, the terminal electrode appears on the surface, and the terminals 13, 14, 15 on the ball silicon surface and the terminals 20, 19, 18 on the substrate recess can be electrically contacted.
In addition, since the insulating film is coated on the TFT element, deterioration of the characteristics of the TFT element can be suppressed.
Further, since the insulating film is coated on the TFT element and the hemispherical side of the insulating film protrudes from the substrate 1 and faces the counter substrate, there is no short circuit with the transparent electrode on the counter substrate side.
[0029]
Note that the outer shape on the hemisphere side where the protective insulating film is left is larger than the inner diameter of the substrate recess 17 shown in FIG.
In addition, the outer shape of the terminal-side hemisphere is made smaller than the inner diameter of the substrate recess.
As a result, only the terminal side of the ball silicon is always inserted into the substrate recess.
A spherical TFT chip is completed by the above process.
Next, a description will be given with reference to FIG.
As shown in FIG. 5, a gate line 3, a source line 4, and a pixel electrode 2 are formed on the substrate 1, and electrically connected to the gate line 3 inside the recess 17. The gate terminal 20, the source terminal 19 electrically connected to the source wiring 4, and the drain terminal 18 electrically connected to the pixel electrode 2 are electrically insulated, and It is formed concentrically.
[0030]
The patterned ball silicon 11 is transferred onto the substrate 1 having the concave portion 17, but when the ball silicon is inserted into the concave portion, the upper and lower sides are not reversed, and the ball silicon is always inserted in a predetermined direction. Even if the electrode is rotated and inserted in the horizontal direction, the electrodes are formed concentrically, so that the source terminals, the gate terminals, and the drain terminals are always contact-connected. As a result, all TFT elements are normal. Actions can be taken.
[0031]
In the embodiment, the terminals 13, 14, 15 on the ball silicon side and the electrodes 20, 19, 18 formed in the hole on the substrate side are both formed concentrically. However, if one of them is concentric, Even if the other is rectangular, the same self-alignment function can be achieved.
[0032]
【The invention's effect】
By using a conventional trapezoidal chip for transfer, compared to the TFT substrate forming method, a spherical ball silicon TFT element is used, and half of the outer shape is enlarged with an insulating film, which is inserted into the recess. Even if the ball silicon element is rotated in the vertical direction, the vertical direction is always inserted normally, and the gate, source and drain electrode terminals are formed in concentric circles. The terminals were connected normally, and the mass productivity and production efficiency increased dramatically.
[0033]
In addition, if one of the ball silicon side terminals 13, 14, 15 and the electrodes 20, 19, 18 formed in the hole on the substrate side is concentric, the same terminals even if the other is rectangular. A self-alignment function between the electrodes can be achieved.
[0034]
In addition, since a protective insulating film is formed on the TFT element, the deterioration of the TFT element is suppressed, an electrical short circuit with the counter electrode is prevented, and the reliability is dramatically increased.
[Brief description of the drawings]
FIGS. 1A and 1B are a plan view and a cross-sectional view showing a configuration in the vicinity of a pixel of an active matrix side substrate in a liquid crystal display device showing an embodiment with a trapezoidal chip. FIGS.
FIG. 2 is a cross-sectional view showing a mounting structure and a mounting method in the vicinity of a trapezoidal chip 7;
FIG. 3 is a diagram showing a form of insertion when a trapezoidal chip is used.
FIG. 4 is a diagram showing an embodiment of a ball silicon electrode structure according to the present invention.
FIG. 5 is a view showing a form in which the ball silicon of the present invention is inserted into a substrate recess.
FIG. 6 is a circuit diagram illustrating a general configuration of a transmissive liquid crystal display device including an active matrix substrate.
FIG. 7 is a cross-sectional view of a TFT portion of an active matrix substrate in a liquid crystal display device when formed by a conventional batch formation technique.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Active matrix substrate 2 Pixel electrode 3 Gate wiring 4 Source wiring 5 Cross part of gate wiring and source wiring 6 TFT
7 Trapezoidal chip 8 Terminal for electrical connection 9 Recess 10 for trapezoidal chip Terminal of hole in first substrate 1 11 Ball silicon 12 TFT
13 Ball silicon source terminal 14 Ball silicon source terminal 15 Ball silicon drain terminal 16 Insulating film 17 Substrate recess 18 Substrate recess drain terminal 19 Substrate recess source terminal 20 Substrate recess gate terminal 21 Gate lead wire 22 Source lead wire 23 Drain lead wiring 101 Active matrix substrate 102 Pixel electrode 103 TFT
104 Gate wiring 105 Source wiring 106 Additional capacitance 107 Common wiring 108 Gate electrode 109 Gate insulating film 110 Semiconductor layer 111 Channel protective layer 112a Source electrode 112b Drain electrode 113a Metal layer 113b Metal layer 114 Pixel electrode 115 TFT
116 Interlayer insulating film 116a Contact hole

Claims (8)

In an active matrix substrate with a spherical semiconductor mounted on the substrate ,
Against spherical semiconductors said substrate, Ri structural der least partially embedded,
At least a part of the surface of the spherical semiconductor is covered with an insulating film,
An active matrix substrate characterized in that an outer diameter of a portion coated with the insulating film is larger than an inner diameter of a hole in a portion where the spherical semiconductor is embedded. 2. The active matrix substrate according to claim 1, wherein an outer diameter of a portion of the spherical semiconductor embedded in the substrate is smaller than an inner diameter of the hole. In claim 1, the implanted portion to the substrate of the spherical semiconductor, the active matrix substrate, wherein the electrode terminal is provided. In claim 1, the active matrix substrate, characterized in that under the insulating film of the portion covered with the insulating film of the spherical semiconductor, a semiconductor element is formed. In claim 3, the active matrix substrate, characterized in that the electrode terminals are formed on the ring, they are arranged mutually insulated and concentrically. 4. The active matrix substrate according to claim 3, wherein both or one of the electrode terminals of the spherical semiconductor or the electrode terminals formed in the holes are concentrically formed. A display device comprising the active matrix substrate according to claim 1. A liquid crystal display device comprising the active matrix substrate according to claim 1.

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