JPS63163885A - Liquid crystal display element and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

[Industrial Application Field 1] The present invention relates to a liquid crystal display element used in office equipment such as a word processor, or a display device for a computer, and more recently, a liquid crystal display element used as a printer printing device as a liquid crystal shutter. This relates to a display method in which a driving circuit is integrally provided for performing the display method. K. Prior Art Conventionally, there are two typical construction methods for liquid crystal display elements for performing this type of high-density display, as described below.The first method is as shown in Fig. 4. Then, one end of a transparent electrode for display is drawn out at a predetermined pitch interval from the end surface of the glass substrate of the liquid crystal cell 11 to form a connection part 11a.
A flat package or chip-shaped liquid crystal driving ICl 3 is disposed on a separately provided printed circuit board 12, and the end surface of this printed circuit board 12 has the same pitch interval as that provided on the liquid crystal cell 11. connection part 12
a, and both connecting parts 11a and 12a are connected by an anisotropic conductive film 14 in which conductive parts are formed in stripes at the same pitch on a flexible film material. The conductive film 14 and both connecting portions 11a112a are connected using a conductive adhesive or the like. The second method is to extend one glass substrate 21a of the liquid crystal cell 21 laterally, as shown in FIG. The transparent electrodes serving as display electrodes are further connected to the liquid crystal driving IC chip 13 by wire bonds 22. [Problems to be Solved by the Invention] However, in the first one, the conductive portion of the anisotropic conductive film 14 is formed by screen printing or the like; There is a limit to the pitch interval, that is, the number of divisions such as a dot matrix that can be implemented in the liquid crystal cell 11 is limited according to this limit value, and there is a large problem that the display density currently required by the user cannot be achieved. This causes problems, and also causes problems such as difficulty in downsizing. In the second example, although the problem of display density has been solved, by extending one glass substrate 21a, a glass substrate with strict flatness requirements and high cost can be used over a large area. In addition, since the liquid crystal cell 21 and the liquid crystal driving IC chip 13 are integrated, the defective factors of both are aggravated, and the yield is lowered, resulting in extremely high costs. Furthermore, since the IC chip 13 is mounted on the glass substrate 21a, the power supply line for this IC chip 13 is naturally also arranged on the glass substrate 2Ia.
It is impossible to arrange this type of wiring with a large current capacity on a glass substrate due to the thickness of the film that can be formed using the vapor deposition method that is normally used to form this type of wiring. Performance problems also arose. Means for Solving Problem K] As a specific means for solving the above-mentioned conventional problems, the present invention provides a terminal section that is electrically connected to a transparent electrode of a display section and capable of wire bonding. and a printed circuit board that supports the liquid crystal cell and has a liquid crystal driving IC chip die-bonded thereto, and the terminal portion and the liquid crystal driving IC chip are connected by wire bonding. The above-mentioned conventional problems are solved by providing a liquid crystal display element and a method for manufacturing the same. Embodiments Next, the present invention will be explained in detail based on embodiments shown in the drawings. What is indicated by the reference numeral 1 in FIG. 1 is a liquid crystal cell, and a wiring circuit has been laid in advance at both ends of the liquid crystal cell 1, and a glass cell with a die-bonded IC chip 3 for driving the liquid crystal.
Printed circuit boards 2X and 2Y using an epoxy base material or a ceramic base material are bonded to each other, and the liquid crystal cell 1 and the liquid crystal driving IC 3 are connected by a wire bond 4 using a gold wire or an aluminum wire. . FIG. 2 shows this state in more detail. The liquid crystal cell 1 consists of two opposing glass substrates 1a and 1b each having a transparent electrode 1e for display, and the outer periphery of the cell 1 is covered with a sealing material. 1C and a liquid crystal 1d is sealed inside.At this time, one glass substrate 1b is formed to be slightly longer than the other glass substrate 1a, and the transparent electrode for display extends to this part. 1e is extended to form a terminal portion 1f.Furthermore, according to the present invention, a gold or aluminum member is metalized by plating or vapor deposition on the display transparent mold ff118 surface of the terminal portion 1f to form a butt 1Q. It is considered suitable for bonding. On the other hand, the printed circuit board 2X is one in which a base 2b or circuits, etc. for mounting a semiconductor are laid by applying photographic technology to a board material 2a made of glass/epoxy laminated material or ceramic as a base material. A liquid crystal driving IC depth 3 is die-bonded to the base 2b. The liquid crystal cell 1 and the printed circuit board 2X described above are bonded together using epoxy resin or the like at the terminal part 1f of the liquid crystal cell 1 as shown in the figure. It is possible to provide the fitting portion 2C in an appropriate shape to facilitate the bonding work. After this adhesion, the batt 1g and the liquid crystal driving IC chip 3 are electrically connected by wire bonding 4 using gold wire or aluminum wire. In addition, the other printed circuit board 2
The same applies to Y, so a detailed explanation will be omitted here. FIG. 3 shows another embodiment of the present invention, in which the previous embodiment has two printed circuit boards 2X. 2Y, this uses a printed circuit board 2Z with an opening 2d in the center, and since the liquid crystal cell 1 is not so large, cutting off the opening 2d and discarding it is costly. This is a method that is effective in reducing the number of steps if adopted when this is not possible, and the other parts are the same as those in the previous embodiment, so a description thereof will be omitted.

【Effect of the invention】

As explained above, according to the present invention, a liquid crystal display element is provided with a liquid crystal cell having a terminal portion that is electrically connected to a transparent electrode of a display portion and capable of wire bonding, and a liquid crystal cell that supports this liquid crystal cell and is used for driving a liquid crystal. It consists of a printed circuit board to which an IC chip is die-bonded, and the terminal part and the liquid crystal drive [C chip are connected by wire bonding, so that it can be connected to a conventional anisotropic conductive film or other material with low wiring density. By making it possible to connect the liquid crystal drive IC chip and the liquid crystal panel without using a cell, it is possible to increase the display density and reduce the size of the display, and at this time, the liquid crystal cell and printed circuit board can be assembled separately. By making it possible to combine good quality products, it is possible to improve yield and reduce costs by eliminating the need for an extended glass substrate.This type of liquid crystal display, which uses matrix drive and other high-density displays, can be used. This has a profound effect that increases the practicality of the device.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a liquid crystal display element and a method for manufacturing the same according to the present invention, FIG. 2 is an enlarged sectional view of the portion indicated by the symbol ■ in FIG. 1, and FIG. A plan view showing another embodiment using a printed circuit board, and FIGS. 4 and 5 are perspective views showing a conventional example. 1...Liquid crystal cell la, 1b...Glass substrate 1C...Sealing material 1d...Liquid crystal 1e...
Transparent electrode 1f... Terminal part 1g... Bats 2X, 2Y, 2Z... Printed circuit board 2a.
...Plate material 2b...Base 2C...Mating part 2d...Opening part 3...LCD drive IC chip 4...Wire bond Fig. 1 Fig. 4

Claims (2)

[Claims] (1) Consists of a liquid crystal cell having a terminal part that is electrically connected to the transparent electrode of the display section and capable of wire bonding, and a printed circuit board that supports this liquid crystal cell and has a die-bonded IC chip for driving the liquid crystal. . A liquid crystal display element, wherein the terminal portion and the liquid crystal driving IC chip are connected by wire bonding. (2) A terminal section that can be electrically connected to the transparent electrode of the liquid crystal cell and wire-bonded is provided, and this liquid crystal cell is connected to the liquid crystal driving I.
1. A method of manufacturing a liquid crystal display element, comprising fixing a C chip to a die-bonded printed circuit board, and connecting the terminal portion and the liquid crystal driving IC chip by wire bonding.