A TFT LCD pixel structure

Abstract

A TFT LCD pixel construction is disclosed, the ring or polygonal TFT component is designed to gate, the via hole part of the pixel is also designed to the gate, the design can increase the W/L of the channel in condition of non-reducing the opening ratio, and increase the on-state current (Ion), the most important is it can limit the post stool (PS) adopted by current color filter.

Description

technical field [0001] The invention belongs to the aspect of TFT LCD pixel structure design, and mainly relates to the design of TFT device structure. Background technique [0002] Most of the currently used TFT LCD pixel structures adopt the structural design shown in Figure 1: [0003] The pixel electrode (ITO) of the TFT is connected to the source (source) through a via hole, and the via hole part is not designed on the gate lead (gate). therefore: [0004] 1. The design of this pixel structure needs to balance the relationship between the two opposing factors of the aperture ratio and whether the pixel is fully charged. In the design of large-scale devices, it is hoped to increase the width-to-length ratio (W / L) to better meet the charging rate requirements. This will increase the width of the conductive channel (channel), increase the size of the TFT, and reduce the The aperture ratio of the device. [0005] 2. This kind of structural design is more complicated, an...

AI Technical Summary

Problems solved by technology

In the design of large-scale devices, it is hoped to increase the width-to-length ratio (W / L) to better meet the charging rate requirements. This will increase the width of the conductive channel (channel), increase the size of the TFT, and reduce the Aperture ratio of the device

[0005] 2. This kind of structural design is more complicated, and there are many factors to be considered

[0006] 3. More importantly, based on the design of this kind of TFT device structure, taking the form of the columnar spacer (PS) of the color filter (CF) on the TFT as an example, the columnar spacer (PS) is vulnerable to damage Damage, forming problems such as box thickness (Gap) and picture defects (mura)

[0007] In general design, the top size (top size) of the cylindrical spacer (PS) is smaller than the bottom size (bottom size), which is approximately a trapezoidal cone structure. After the box alignment process, the upper end of the cylindrical spacer (PS) has a certain As shown in the circular area in Figure 2, when the panel surface is subjected to external force, the color filter substrate is easy to move relative to the array substrate, and because the contact surface between the columnar spacer (PS) and the TFT is in the On the ridges of the source and drain (S / D), the unevenness of the surface is likely to cause damage to the upper end surface of the columnar spacer (PS). At the same time, because the two are not in surface contact, the pressure on the contact end will be very large. This may also cause damage to the TFT pixel electrode (ITO), as shown in Figure 3

[0008] 4. At the same time, this design cannot well limit the movement of the upper end of the column spacer (PS) on the array substrate (array). Under the action of external force, the slight movement of the color filter (CF) will exceed the The upper limit of the specification may cause white mura or zaratsuki light leakage

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