JP3036151B2 - Tape carrier package for LCD driver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape carrier package for driving a liquid crystal used in a liquid crystal display device.
age) (hereinafter, referred to as TCP for LCD driver), particularly a portable personal computer (hereinafter, referred to as a notebook PC) which is small, light, thin, and low in power consumption and has excellent portability. The present invention relates to an LCD driver TCP suitable for a word processor (hereinafter, referred to as a word processor) or the like.

[0002]

2. Description of the Related Art At present, notebook personal computers (hereinafter referred to as notebook PCs) are two-thirds of laptop personal computers (hereinafter referred to as laptop PCs).
Called a personal computer. ) It has reached 30% of the total, and in a few years, this portable notebook PC is expected to make up the majority of the entire personal computer.

[0003] Under such circumstances, the most suitable TCP for LCD driver as a liquid crystal display for notebook PC is 8
A narrow TC mounted with an elongated rod-shaped liquid crystal driving LSI chip with 0 channel output or 160 channel output
There has been proposed a TCP for LCD driver called P system, so-called slim TCP or micro TCP (hereinafter referred to as slim TCP).

In this method, the width of the TCP is reduced by optimizing the wiring of the TCP tape with respect to the wiring pitch of the liquid crystal panel using an LSI chip having pads arranged around the LSI chip (in four directions). We are trying to minimize it. That is, the bent portion of the wiring pattern of the TCP tape is minimized so that the outer lead pitch of the TCP matches the pad pitch of the LSI chip as much as possible. Therefore, the aspect ratio of the LSI chip is 1: 8.5 to 1:10, and the shape is a bar.

However, in order to adjust the pad pitch of the LSI chip to the outer lead pitch of the TCP, the aspect ratio of the LSI chip becomes large, and bonding is performed in order to reduce stress on the LSI chip during inner lead bonding. It is obvious that various measures are required, such as flattening of the tool and the bonding stage and increasing the precision of the inner lead bonder.

It is also obvious that miniaturization of the LSI chip is most effective in reducing the price of the LCD driver TCP.

Therefore, the prior art is effective for miniaturization, but the overall yield of TCP for LCD drivers, ie, the yield of LSI chips, the yield of TCP tapes,
No consideration has been given to the yield when the LSI chip is mounted on the CP tape. In other words, the slim TCP for the LCD driver has not been sufficiently considered for achieving both miniaturization and cost reduction.

[0008]

The above prior art is based on
No consideration has been given to achieving both a reduction in the width of the TCP for the CD driver and an increase in the production yield. Therefore, when this TCP for LCD driver is used, a small, light and thin liquid crystal module can be realized.
In addition, there is a limit in that the notebook PC itself is small, light, and thin.

An object of the present invention is to propose a small and thin TCP for an LCD driver which is optimal for a liquid crystal display for a notebook PC, and to reduce a frame by adapting the TCP for an LCD driver of the present invention to a liquid crystal display. ,
An object of the present invention is to reduce the size, weight, and thickness of OA devices such as word processors and notebook PCs which are excellent in portability.

[0010]

The object of the present invention is to optimize the relationship between the LSI chip size (aspect ratio of the LSI chip), the yield of TCP tape production, and the yield of mounting the LSI chip on the TCP tape by experiments. By specifying the chip size, the optimum width for notebook PC is narrow, L
Achieving slim TCP for CD drivers.

[0011]

By specifying the LSI chip size, in particular, the aspect ratio of the LSI chip, it is possible to manufacture TCP tapes and TC
By increasing the yield of mounting the LSI chip on the tape for P, the size of the slim TCP for the LCD driver can be reduced.

Also, the slim T for LCD driver of the present invention.
By using the CP, a liquid crystal display with a small frame, small size, light weight and low cost can be achieved. Furthermore, a small and lightweight notebook PC can be achieved by using this liquid crystal display.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a TCP for an LCD driver for carrying out the present invention will be described in detail with reference to the drawings.

However, in this embodiment, a description will be given by taking as an example a TCP for an LCD driver which is a bar-shaped LSI chip having a large aspect ratio, and has a 160-channel output and a 140 μm outer lead pitch of TCP in which pads are arranged around the chip.

The TCP for LCD driver uses TAB (Tape Automated BTA) using a tape wired with a copper foil pattern.
Onding) technology, an LSI chip for driving a liquid crystal is mounted.

First, the appearance and structure of the LCD driver TCP of the present invention will be described in detail with reference to FIGS. FIG. 1 shows its appearance, and FIG. 2 shows its cross-sectional structure.

FIG. 1 is an external view of a TCP for an LCD driver according to the present invention. In the figure, 1 is a base tape, 2 is an LSI chip, 3 is an output outer lead, 4 is an input outer lead, 5 is an output wiring, 6 is an input wiring, 7 is an input wiring.
Is an inner lead, 8 is a device hole, 9 is an input outer lead hole, 10 is a solder resist, and 11 is a sprocket hole (or perforation).

As shown in FIG.
Patterns were arranged on a polyimide film having a width of 4 mm at a pitch of 4 perforations. In addition, the outer lead portion 3,
4 was arranged in a pattern so as to be perpendicular to the sprocket hole 11. That is, since a particularly large stress is applied in the vicinity of the sprocket hole 11 during the production of the tape carrier, the outer lead portions 3 and 4, which require high dimensional accuracy, are not disposed near the sprocket hole 11 and in a direction different from the stress direction. By arranging them, the cumulative dimensional tolerance of the outer lead portions 3 and 4 was minimized.

FIG. 2 shows a sectional structure of a TCP for an LCD driver according to the present invention. In the figure, 1 is a base tape, 2
Is an LSI chip, 3 is an output outer lead, 4 is an input outer lead, 5 is an output wiring, 6 is an input wiring,
7 is an inner lead, 8 is a device hole, 9 is an input outer lead hole, 10 is a solder resist, 12 is an adhesive, 13 is a bump, and 14 is a sealant.

As shown in the figure, the TCP for LCD driver of the present invention has a three-layer structure, that is, a structure composed of a base tape 1 / adhesive 12 / copper foil patterns 3, 4, 5, 6, and 7.

The TCP for an LCD driver of the present invention is a structure of a different material, and there are several combinations. In this embodiment, the most common combination, 7
5 μm-thick polyimide film (Kapton V, Upilex S), epoxy-based adhesive as adhesive 12, 35-μm-thick copper foil (rolled copper foil, electrolytic copper foil) as wiring material 3, 4, 5, 6, 7 3) An epoxy resin was used as the sealing material 14, an epoxy solder resist was used for the solder resist 10, and a solder plating was used for plating the outer leads 3, 4, 5, 6, and 7.

In this embodiment, the outer leads 3 and
4. Solder plating is used for plating the inner leads 7 and the wiring portions 5 and 6. However, tin plating and gold plating may be used, and the plating is determined in consideration of the reliability of the wiring pitch of the outer leads 3 and 4 and chemical migration. Should.

In this embodiment, a three-layer structure, namely, base tape 1 / adhesive 12 / copper foil patterns 3, 4, 5,
Although a tape having a structure composed of 6, 7 was used, but a tape having a two-layer structure without using an adhesive, that is, a tape composed of a base tape 1 / copper foil pattern 3, 4, 5, 6, 7 was used.
It is obvious that dimensional accuracy and various reliability are improved.

FIG. 3 shows the aspect of the TCP for the LCD driver according to the present invention, which is the aspect ratio of the LSI chip, the production yield of the TCP tape, the yield when the LSI chip is mounted on the TCP tape, and the length of the TCP for the LCD driver. Shows the relationship. In the figure, reference numeral 15 denotes a yield of manufacturing a TCP tape, 16 denotes a yield when an LSI chip is mounted on the TCP tape, and 17 denotes a curve indicating a TCP width for an LCD driver.

As shown in the drawing, the production yield 15 of the TCP tape is maximized when the aspect ratio of the LSI chip is in the range of 4.0 to 7.0, and when the LSI chip is mounted on the TCP tape. The yield 16 tends to simply decrease as the aspect ratio of the LSI chip increases. The TCP length 17 for the LCD driver tended to be almost the minimum when the aspect ratio of the LSI chip was 4.0 or more.

From the figure, it can be seen that a high yield and a T
The aspect ratio of the LSI chip that can produce a CP and minimize the TCP width for LCD driver is 4.0
It was found to be in the range of ~ 7.0.

Further, by arranging the wiring so that the lead interval is substantially constant, it is possible to achieve a tape carrier with good etching accuracy and few short-circuit breaks.
Distance and LS from SI chip to output outer lead
It was also confirmed that if the wiring patterns were arranged so that the ratio of the distance from the I chip to the outer lead on the input side was approximately 3 or more, it was effective for the tape production yield.

FIG. 4 shows the structure of a color liquid crystal module using the LCD driver TCP of the present invention. In the figure, 2 is a liquid crystal driver LSI chip, 18 is a liquid crystal display panel, 19 is a micro TCP of the present invention, 20 is a printed board, 21 is a cold cathode tube, 22 is a light guide, 23 is a reflection sheet, and 24 is a diffuser. Sheet, 25 is a reflection sheet for a lamp,
26 is a double-sided adhesive tape, 27 is a lamp guide, 28 is a white reflective film, and 29 is a metal frame.

In the figure, a super TN color liquid crystal panel is used for the liquid crystal display panel 18, and the backlight is a 3 mm thick acrylic plate for the cold cathode tube 21, a 3 mm thick acrylic plate for the light guide 22, and a thick plate for the reflective sheet 23. A polyester sheet having a thickness of 0.125 mm, a diffusion sheet 24 having a thickness of 0.1 mm, a reflecting sheet 25 for lamps having a 0.125 mm thick polyester sheet with silver deposited thereon, and a double-sided adhesive tape 26 having a nonwoven fabric. An acrylic adhesive, a silicone rubber for the lamp guide 27, a polyester ink containing titanium oxide as a main component for the white reflection film 28, or an acrylic ink containing titanium oxide as a main component, and a metal frame 29 for the thickness. It consisted of a 0.5 mm stainless steel plate.

As shown in FIG.
P19 is arranged above the cold-cathode tube 21 and mounted about 8 mm wide from the end of the liquid crystal panel 18. The liquid crystal panel 17, the thin backlight comprising the cold cathode tube 21, the light guide 22 and the like were integrated by a metal frame having a thickness of 0.5 mm. With this configuration, the module thickness is 7.5 mm, the module weight is 500 g, and the power consumption is 4.2.
A color liquid crystal module for a notebook PC of W 1 was achieved.

FIG. 5 shows the LCD driver T of the present invention.
The configuration of a notebook PC color liquid crystal panel using CP19 is shown. The color liquid crystal panel 18 shown in the figure has a display scale of 640 (× 3) × 400 dots (pixel pitch: 0.27 m
mx 0.27mm, pixel size: 0.255mm x 0.255m
m, screen diagonal size: 8.0 inches, upper and lower electrode substrates (material: soda lime glass, thickness: 0.7 mm) 131, 132, liquid crystal 140, birefringent film ( Nitto Denko: uniaxially stretched polycarbonate film 121, upper and lower polarizing plates (Nitto Denko: G12)
(20 DU, transmittance: 40%) 111, 112. The lower electrode substrate 132 has a black matrix (pigment type, thickness: 0.7 to 1.3 μm) 137, a color filter (pigment type, thickness: 1.5 to 2.5 μm) 138, and a smoothing film (epoxy). Based resin, thickness: 0.7 to 1.3 μm)
Lower transparent electrode (ITO, sheet resistance: 15Ω / □) 13
3. Alignment film (polyimide resin, thickness: 0.07 to 0.1)
On the other hand, an upper transparent electrode (ITO, sheet resistance: 15Ω) is formed on the upper electrode substrate 131.
/ □) 134, insulating film (film material: SiO ₂ , thickness: 0.07)
.About.0.13 .mu.m) 135 and an alignment film 136 are formed.

The alignment film 136 on the upper and lower electrode substrates 131 and 132 is subjected to a rubbing process, and
Liquid crystal (Merck mixed liquid crystal, liquid crystal layer thickness: 6μ)
m) A spiral structure was formed in which 140 was twisted 260 degrees.

Further, on the opposite side of the lower electrode substrate 132 where the color filter 138 is formed, the birefringent film 12 is formed.
1, lower polarizing plate 112, upper electrode 1 of upper electrode substrate 131
An upper polarizing plate 111 was disposed on the side opposite to the side where 34 was formed.

FIG. 3 shows a configuration in which a color filter is formed on the lower electrode substrate 132 having a small number of electrodes for ease of electrode formation. However, considering the ease of assembling the liquid crystal panel, the color filter is formed on the upper electrode substrate. It is advantageous to form

The color liquid crystal display element 18 described above is thin and
The backlight unit 30 has low power consumption. The backlight unit 30 is roughly divided into a light guide plate (material: acrylic, thickness: 3 mm) 22, a cold cathode tube (manufactured by Matsushita:
K-C240T4E72, pipe diameter: 4 mm, 21, reflective sheet (diafoil: W-400, thickness: 0.125 m)
m) 25, diffusion sheet (made by Kimoto: D-204, thickness:
0.1mm) 24, reflective sheet for cold cathode tubes (KIMOTO: GR
−38 W, thickness: 0.1 mm) 25, double-sided adhesive tape (Nitto Denko: No. 500) 26, guide (silicon rubber) 157 for cold cathode tubes, white reflective film (dispersant: titanium oxide,
(Base material: polyester-based resin) 28.

A pigment-dispersed black matrix (width: 25 μm) 137 formed by photolithography is arranged on the lower electrode substrate 112 at a pitch of 90 μm, and a pigment-dispersed color matrix formed by printing is formed thereon. Filter 138 was placed.

The color filter 138 is formed by dispersing an organic pigment or an inorganic pigment in a melamine epoxy resin, and has a film thickness set in a range of 1.5 μm to 2.5 μm. Also, the black matrix 137
Is mainly obtained by dispersing carbon in an acrylic resin, and has a thickness of 0.7 μm to reduce the transmittance to 2% or less.
The one set in the range of 1.3 μm was used.

The pigment type black matrix 13
The use of conventional chromium (film thickness: 0.1 μm)
m) as compared with a color liquid crystal display device using a black matrix formed by the above method.

In this embodiment, the color filter 138 is used.
Are formed under the lower substrate side transparent electrode 134 by a printing method because of the advantage of forming the electrodes 133 and 134, and the black matrix is formed by a photolithography method. However, in order to provide an inexpensive color liquid crystal panel, the printing method is used. It is desirable to form a black matrix by the following.

In order to form a black matrix by a printing method, it is necessary to form a high-precision alignment mark or obtain an equivalent mark on the mark so as to obtain an overlay accuracy with a lower electrode formed on a color filter. It is necessary to devise such a method as to obtain the accuracy. That is, when a color filter is formed on the lower electrode side, the alignment mark,
Another important point is the alignment between the color filter formed below the lower electrode and the upper electrode. In this regard, if a color filter is formed below the upper electrode, the alignment between the lower electrode and the upper electrode becomes easier.

In the color liquid crystal display device of the present invention, the thickness of the liquid crystal layer and its uniformity are important factors which influence the display characteristics of brightness, contrast and color range. In order to make the thickness of the liquid crystal layer uniform, it is desirable to form a color filter with the same smoothness as the upper and lower electrode substrates.

In the color liquid crystal display device of the present invention, the dispersion amount of the pigment of the color filter or the spectral transmittance characteristic is specified so that the three characteristics of the color filter, namely, the smoothness, the color purity, and the transmittance are satisfied in a well-balanced manner. By doing so, it is possible to use a backlight having a configuration in which a fluorescent discharge tube is arranged on the side surface of the light guide, thereby achieving a reduction in thickness, weight, and power consumption.

In the color liquid crystal display device of the present invention, the point of the pigment dispersion type color filter 138 formed by this printing method is a point, and the balance of these three characteristics on the color filter 138, such as smoothness, color purity and transmittance. In consideration of,
Through experiments, the amount of pigment dispersion in the color filter was optimized.

FIG. 6 shows the relationship between the amount of pigment dispersion and the transmittance, contrast ratio, and stimulus purity. As shown in the figure,
If the lower limits of the transmittance, the contrast ratio and the stimulus purity are respectively set to T = 5%, Cr = 10, Pr = 10%,
The range of the pigment dispersion amount satisfying all three characteristics is approximately 25
It has been found that the setting should be made in the range of% to 5%. However, the thickness of the color filter at this time is approximately 1.5 μm.
It is important to specify within the range of .about.2.5 .mu.m. That is, the spectral transmittance characteristic of the color filter is determined substantially by the product of the amount of dispersion of the pigment and the film thickness of the color filter.

In consideration of the balance between the three display characteristics of brightness, contrast, and color specification range, the thickness of the module, and the power consumption, the dispersion amount of the pigment is preferably 23% to 8%.
%, The thickness of the color filter is approximately 1.7 μm to 2.
It turned out that it is sufficient to specify the range of 3 μm. Therefore,
In this embodiment, a color filter 138 having a pigment dispersion amount of about 15% is provided.

FIG. 7 shows the spectral transmittance characteristics of the color filter 138 in which the dispersion amount of the pigment is approximately 15% and the film thickness of the color filter is approximately 2 μm, and the pigment dispersion used in the conventional laptop personal computer. The spectral transmittance characteristic of the color filter specified with a dispersion amount of approximately 30% and a film thickness of the color filter of approximately 2 μm is shown. In the figure, 410 and 411 are red spectral characteristics, and 420 and 421.
Indicates the spectral characteristics of green, and 430 and 431 indicate the spectral characteristics of blue.
Color filters identified as 5%, 411, 421, 43
Reference numeral 1 denotes a color filter in which the amount of pigment dispersion is specified to be about 30%. As shown in the figure, the transmittance in the wavelength region other than the intended color is increased, contrary to the conventional one, to improve the transmittance of the color filter and to improve the smoothness of the color filter as compared with the conventional one. The point is that it has been improved about three times.

However, the stimulus purity of the color filter of the present invention is slightly lower than that of a color filter having a pigment dispersion of about 30% used in a conventional laptop personal computer. Therefore, the color filter of the present invention is a light color filter as compared with the conventional color filter.

In order to use such a light color filter, the white balance using only the color filter, or the white balance in the combination of the color liquid crystal display element 18 and the backlight unit 30 in the module configuration shown in FIG. Considering black balance,
It is important to make the spectral transmittance characteristics.

As described above, by combining the liquid crystal driver TCP of the present invention with a liquid crystal panel using a light color filter, a small, lightweight, low power consumption and low cost color liquid crystal module can be achieved.

[0050]

According to the present invention, a TCP for a liquid crystal driver is provided.
Can be reduced in size and cost. Further, by applying the liquid crystal driver TCP of the present invention to a liquid crystal display, the frame can be reduced,
This has the effect of reducing the size, weight, and thickness of OA devices such as word processors and notebook PCs that are excellent in portability.

[Brief description of the drawings]

FIG. 1 is a view showing the appearance of a TCP for an LCD driver according to the present invention.

FIG. 2 is a diagram showing a cross-sectional structure of a TCP for an LCD driver of the present invention.

FIG. 3 is a diagram showing the relationship between the LSI chip aspect / width ratio and the tape, inner lead bonding yield, and TCP width.

FIG. 4 is a view showing a cross-sectional structure of a color liquid crystal module using the LCD driver TCP of the present invention.

5 is a diagram showing a cross-sectional structure of the color liquid crystal panel shown in FIG.

FIG. 6 is a diagram showing the relationship between the amount of dispersion of a pigment in a color filter used in the color liquid crystal panel shown in FIG. 5, and transmittance, contrast ratio, and stimulus purity.

FIG. 7 is a diagram showing spectral characteristics of a color filter used in the color liquid crystal panel shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base tape, 2 ... LSI chip, 3 ... Output side outer lead, 4 ... Input side outer lead, 5 ... Output side wiring, 6 ... Input side wiring, 7 ... Inner lead, 8 ... Device hole, 9 ... Outer lead Hole, 10: solder resist, 11: sprocket hole, 12: adhesive, 1
3 ... Bump, 14 ... Sealant, 15 ... Tape production yield curve, 16 ... LSI chip mounting yield curve, 17 ... TCP
Width curve, 18: color liquid crystal panel, 19: TCP for liquid crystal driver, 20: printed board, 21: cold cathode discharge tube, 2
2: light guide plate, 23: reflection sheet, 24: diffusion sheet, 2
5. Reflecting sheet for lamp, 26 ... Double-sided adhesive tape, 27
... Lamp guide, 28 ... Printed reflective film, 29 ... Metal frame, 30 ... Backlight.

Continuation of the front page (72) Inventor Yuzo Morita 4-6 Kanda Surugadai, Chiyoda-ku, Tokyo Hitachi, Ltd. (56) References JP-A-4-50820 (JP, A) JP-A-1-2511079 (JP) JP-A-3-175060 (JP, A) JP-A-4-114026 (JP, U) JP-A-1-145131 (JP, U) (58) Fields studied (Int. Cl. ⁷ , DB Name) G02F 1/1345 G02F 1/1333 G09F 9/00 H01L 21/60

Claims (4)

(57) [Claims] 1. A organic insulating tape 35mm wide with a semiconductor integrated circuit device mounting the device hole and a plurality of sprocket holes, subjected bonded to organic insulating tape, a semiconductor integrated circuit device Bonn
Inner lead for output, and output and input outer
-The metal foil layer on which the lead wiring pattern is formed, and the inner lead, in the width direction of the organic insulating tape.
On the other hand, they were arranged and connected so that their longitudinal directions were parallel,
The aspect ratio is about 4 or more and the output of 80 channels or more
A tape carrier package for a liquid crystal driver having a semiconductor integrated circuit element . 2. The tape carrier package for a liquid crystal driver according to claim 1, wherein said semiconductor integrated circuit device is arranged within four sprockets of a sprocket hole of said organic insulating tape. 3. The semiconductor integrated circuit device has an aspect ratio of about 4
The tape carrier package for a liquid crystal driver according to claim 1 , wherein the tape carrier package is not less than about 7 or less . (4) Wiring pattern of the semiconductor integrated circuit device
Is the output-side outer library from the semiconductor integrated circuit element.
Distance from the semiconductor integrated circuit device to the input
The ratio of the distance to the force side outer lead will be about 3 or more
4. The liquid crystal driver according to claim 1,
Tape carrier package for EVA.