Transmission type liquid crystal display having an organic interlayer elements film between pixel electrodes and switching

Abstract

The transmission type liquid crystal display device of this invention includes: gate lines; source lines; and switching elements each arranged near a crossing of each gate line and each source line, a gate electrode of each switching element being connected to the gate line, a source electrode of the switching element being connected to the source line, and a drain electrode of the switching element being connected to a pixel electrode for applying a voltage to a liquid crystal layer, wherein an interlayer insulating film formed of an organic film with high transparency is provided above the switching element, the gate line, and the source line, and wherein the pixel electrode formed of a transparent conductive film is provided on the interlayer insulating film.

Description

[0001] 1. Field of the Invention[0002] The present invention relates to a transmission type liquid crystal display device which includes switching elements such as thin film transistors (hereinafter, referred to as "TFTs") as addressing elements and is used for displays of computers, TV sets, and the like, and a method for fabricating such a transmission type liquid crystal display device.[0003] 2. Description of the Related Art[0004] FIG. 16 is a circuit diagram of a conventional transmission type liquid crystal display device provided with an active matrix substrate.[0005] Referring to FIG. 16, the active matrix substrate includes a plurality of pixel electrodes 1 arranged in a matrix and TFTs 2 used as switching elements connected to the respective pixel electrodes 1. Gate electrodes of the TFTs 2 are connected to gate lines 3 for supplying a scanning (gate) signal, so that the gate signal can be input into the gate electrodes to control the driving of the TFTs 2. Source electrod...

AI Technical Summary

Benefits of technology

[0058] Thus, the invention described herein makes possible the advantage of (1) providing a transmission type liquid crystal display device where flat pixel electrodes overlap respective lines to improve the aperture ratio of the liquid crystal display, minimize disturbance in the orientation of liquid crystal molecules, and simplify the fabrication process. Furthermore, and the influence of the capacitance between the pixel electrodes and the lines appearing on the display, such as crosstalk, can be reduced to achieve a good display. The invention described herein also makes possible the advantage of (2) providing a method for fabricating such a transmission type liquid crystal display device.

Problems solved by technology

Therefore, when the pixel electrode 1 is formed on the transparent insulating film, steps will be formed on the pixel electrode 1 if the underlying film has steps, causing disturbance in the orientation of liquid crystal molecules.

This is not suitable for a liquid crystal display device requiring high light transmission and transparency.

Incidentally, in order to obtain a thicker inorganic film made of silicon nitride and the like, an undesirably long time is required in the aspect of the fabrication process.

However, it is not effective for a color display panel for normal notebook type personal computers and the like where pixel electrodes are arranged in a vertical stripe shape (in color display, a square pixel is divided into three vertically long rectangular picture elements representing R, G, and B, forming a vertical stripe shape).

Accordingly, the proposed driving method of inverting the polarity of the data signal every source line is not effective in reducing crosstalk for the general color display, though it is effective for the black-and-white display.

With this conventional structure, however, when the TFT is made smaller to improve the aperture ratio, for example, it is not possible to accommodate the entire contact hole above the smaller TFT.

As a result, the aperture ratio is not improved.

In the conventional active matrix substrate, if a TFT with a size smaller than this value is realized, the oversized connecting electrode causes a new problem of lowering the aperture ratio.

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