CN101017291A - Pixel structure of thin film transistor liquid crystal display - Google Patents

Abstract

A pixel structure of a thin film transistor liquid crystal display is disclosed, wherein an organic insulation layer is arranged between a data signal line and a common electrode to reduce parasitic capacitance by using the design of three metal layers, and a passivation layer is arranged between the common electrode and a pixel electrode to be used as a storage capacitor required by a pixel, so as to achieve the design of high aperture ratio. In addition, the common electrode is used as a light shielding layer to improve the contrast of display.

Description

The dot structure of Thin Film Transistor-LCD

Technical field

The present invention relates to a kind of LCD, particularly a kind of dot structure of Thin Film Transistor-LCD.

Background technology

LCD (Liquid Crystal Display; LCD) because of having the compact advantage of low radiation and volume, so its use is increasingly extensive, and Thin Film Transistor-LCD (Thin Film Transistor LCD; TFT LCD) because the characteristics at its contrast and visual angle still is the main flow display at present on market.

Because liquid crystal material itself is not luminous, the light source of TFT LCD is from the behind light source, each layer of this behind light source process TFT LCD is as polaroid, colored filter materials such as (color filter), and the real brightness that shows approximately has only about 10% of former illuminating source.For the problem of display brightness deficiency,,, improve the power attenuation of panel module though panel luminance is increased if improve backlight module brightness; And improve the panel aperture opening ratio, and though can increase the panel display brightness, how to improve the aperture opening ratio of the pixel (pixel) on the display panel, be still the problem that all panel dealers are devoted to solve at present.

See also Fig. 1, Fig. 1 is a prior art dot structure synoptic diagram, this dot structure comprisesTFT structure 1a, thepixel electrode 7a that forms by the formedscan signal line 3a of first conductive metal layer, light shield layer (shielding bar) 2a andpublic electrode 4a,active area 5a, by the formed data signal line 6a of second conductive metal layer, transparency conducting layer, its mode of making storage capacitors be by the formedpublic electrode 4a of first conductive metal layer with form electric capacity by the regional 8a of the corresponding overlapping ofTFT structure 1a source electrode.Andlight shield layer 2a is responsible for the light of the inner unnecessary backlight module of blocking LCD in order to prevent light leak, and the light source between each pixel can not be interfered with each other, and improves the contrast of display degree.Yet under the situation of certain area, the aperture opening ratio of this method for designing will can be too not high, the requiredoverlapping zone 8a of this storage capacitors will occupy some zones of pixel andlight shield layer 2a will make aperture opening ratio reduce because form, under the trend of high resolving power (Pixel Dimensions diminishes) development, this method for designing does not more meet the market demand for display panel.

Fig. 2 is another prior art pixel layout synoptic diagram, the prior art structure of its pixel design and Fig. 1 is roughly the same, compriseTFT structure 1a, thepixel electrode 7a that forms by the formedscan signal line 3a of first conductive metal layer andpublic electrode 4a,active area 5a, by the formed data signal line 6a of second conductive metal layer, transparency conducting layer, its mode of making storage capacitors be by the formedpublic electrode 4a of first conductive metal layer with form electric capacity by the regional 8a of the corresponding overlapping ofTFT structure 1a source electrode; The maximum difference point of this design and Fig. 1 prior art is when the second metal level film forming, again by chemical gas-phase deposition method coating one deck passivation layer (passivation) 11a, and then theorganic insulator 10a of coating one deck low-k, plate transparency conducting layer (passivation layer 11a, substrate 12a, gate insulator 13a in the C-C crosscut sectional view as shown in Figure 3) at last again, the fundamental purpose of above-mentioned making organic insulator is to reduce data signal line and the formed stray capacitance of pixel electrode, to avoid producing (crosstalk) phenomenon of crosstalking.Because the designed structure of Fig. 2, though compared high aperture opening ratio with the prior art of Fig. 1, but this pixel design must additionally provide certain area to serve as the storage capacitors of pixel, and this kind design still has sizable space of improving when the design resolution panels.

Summary of the invention

Fundamental purpose of the present invention is to improve the shortcoming that exists in the prior art, when no matter its fundamental purpose is to be applied to the height resolution panel, all can promote pixel aperture ratio, to improve the pixel quality, reducing relatively needs to strengthen the power attenuation that backlight module brightness caused.

To achieve these goals, the dot structure of Thin Film Transistor-LCD of the present invention comprises substrate, first conductive metal layer is covered on this substrate, follow continuous film forming first insulation course (gate insulator) on described first conductive metal layer, amorphous silicon (a-Si:H) intrinsic layer and n+Si Ohmic contact (Ohmic Contact) film, form second conductive metal layer then, second insulation course is covered on described second conductive metal layer, organic insulator is covered on described second insulation course, the 3rd conductive gold layer is covered on the described organic insulator, passivation layer is covered on described the 3rd conductive metal layer, and transparency conducting layer is covered on the described passivation layer; Characteristics of the present invention are to reduce the stray capacitance of second conductive metal layer-data signal line and the 3rd conductive gold layer-public electrode (Vcom) formation by the organic insulator of described low-k, the pixel electrode that utilizes public electrode and this transparency conducting layer to form simultaneously inserts and puts passivation layer with as the required storage capacitor structure of pixel, the opaqueness of public electrode (Vcom) of arranging in pairs or groups again prevents light leak, be responsible for the light of the inner unnecessary backlight module of blocking LCD, light source between each pixel can not interfered with each other, improve the contrast of display degree.

Description of drawings

Fig. 1 is the pixel layout synoptic diagram of prior art;

Fig. 2 is the pixel layout synoptic diagram of another prior art;

Fig. 3 is the section cross-sectional schematic of Fig. 2 in the C-C position;

Fig. 4 is a layout structure synoptic diagram of the present invention;

Fig. 5 is the section sectional structure synoptic diagram of Fig. 4 in A-A ' position;

Fig. 6 is a layout structure synoptic diagram of the present invention;

Fig. 7 is the section sectional structure synoptic diagram of Fig. 6 in B-B ' position;

Fig. 8 is a layout structure synoptic diagram of the present invention;

Fig. 9 is the section sectional structure synoptic diagram of Fig. 8 in C-C ' position;

Figure 10 is a layout structure synoptic diagram of the present invention;

Figure 11 is the section sectional structure synoptic diagram of Figure 10 in D-D ' position;

Figure 12 is the section sectional structure synoptic diagram of Figure 10 in E-E ' position;

Figure 13 is a layout structure synoptic diagram of the present invention;

Figure 14 is the section sectional structure synoptic diagram of Figure 13 in F-F ' position;

Figure 15 is a layout structure synoptic diagram of the present invention;

Figure 16 is the section sectional structure synoptic diagram of Figure 15 in G-G ' position;

Figure 17 is a layout structure intention of the present invention;

Figure 18 is the section sectional structure synoptic diagram of Figure 17 in H-H ' position;

Figure 19 is the section sectional structure synoptic diagram of Figure 17 in I-I ' position.

In the accompanying drawing, the list of parts of each label representative is as follows:

TFT structure 9scan signal lines 11

Active area 10data signal lines 3

Public electrode 6pixel electrode layers 101

Organic insulator 5substrates 1

First insulation course, 21grids 12

A-Si:H intrinsic layer 22 n+SiOhmic contact films 23

Second insulation course, 4passivation layers 7

Contacthole 8 thin film transistor (TFT)source electrodes 31

Thin film transistor (TFT)drain electrode 32

Prior art

TFT structure 1alight shield layer 2a

Scan signal line 3apublic electrode 4a

Active area 5a data signal line 6a

Thepixel electrode 7a regional 8a that overlaps

Gate insulator 13aorganic layer 10a

Passivation layer 11a substrate 12a

Embodiment

About technology contents of the present invention and detailed description, existing accompanying drawings is as follows:

Fig. 4-the 19th, the pixel of LCD of the present invention is made flow implementation example structure.The dot structure of Thin Film Transistor-LCD of the present invention mainly is in order to improve pixel aperture ratio, to increase brightness and to promote the panel display quality, to promote product competitiveness.

The dot structure of Thin Film Transistor-LCD of the present invention comprises:TFT structure 9, by the formedscan signal line 11 of first conductive metal layer,active area 10, by the formeddata signal line 3 of second conductive metal layer, the 3rd conductive layer-public electrode 6, transparency conducting layer-pixel electrode 101 andsecond insulation course 4, and dot structure manufacture process of the present invention is as follows:

At first, getsubstrate 1, thissubstrate 1 is made by hard material (as glass) or softwood matter (plastics);

Utilize coating apparatus with the first conductive metallic material film forming onaforesaid substrate 1 surface, to form first conductive metal layer (shown in the layout structure of Fig. 4 and shown A-A ' position section sectional structure shown in Figure 5 of Fig. 4), this first conductive metal layer forms thegate electrode 12 of TFT structure and thescan signal line 11 of pixel, group or its combination in any that the described first conducting metal layer material uses molybdenum (Mo), tantalum (Ta), chromium (Cr), tungsten (W), aluminium (Al) and aluminium alloy to form perhaps also can be made multilayer (Multilayer) according to demand.

On the described first conducting metal laminar surface, form first insulation course 21 (as the SiNx silicon nitride) and semiconductor layer (as the B-B ' position section sectional structure that shown Fig. 6 shown in Figure 7), the film forming of wherein said semiconductor layer is to adopt electricity slurry assistant chemical vapor deposition (PECVD) equipment to carry out the deposit of a-Si:H (hydrogeneous amorphous silicon)intrinsic layer 22 and n+Si Ohmiccontact film 23 in a continuous manner, wherein a-Si:Hintrinsic layer 22 is continuous film formings withfirst insulation course 21 of SiNx, and this way can obtain the interface of SiNx and a-Si:H semiconductor film preferably;

Then, utilize photoetching process to form the required semiconductor layer pattern of this thin film transistor (TFT) (as Fig. 8 and shown in Figure 9); Utilize sputtering technology to plate second conductive metal layer (shown in the layout structure synoptic diagram of Fig. 8) again on said n+SiOhmic contact film 23 surfaces, utilize the photoetching process to form the pattern ofdrain electrode 32,source electrode 31 and thedata signal line 3 of thin-film transistor structure, use the dry ecthing mode etching n+SiOhmic contact film 23 of channel end (as having shown Fig. 8 shown in Figure 9 at C-C ' position section sectional structure) dorsad then; Utilize thin-film technique chemical vapor deposition second insulation course 4 (shown in the layout structure synoptic diagram of Figure 10) ondrain electrode 32,source electrode 31 anddata signal line 3 then;

Then, aftersecond insulation course 4 forms, utilize rotary coating machine (spin coater) second insulation course, 4 surface coated one deck organic insulators 5 (as shown Figure 10 at Figure 11 of D-D ' position section sectional structure and shown Figure 10 shown in Figure 12 at E-E ' position section sectional structure);

After being coated with above-mentionedorganic planarization layer 5, form contact hole 8 (contact hole), plate the 3rd conductive metal layer by the sputter mode onorganic insulator 5 surfaces again, form the pattern (shown in the layout structure of Figure 13 and shown Figure 13 shown in Figure 14 at F-F ' position section sectional structure) of pixel required public (Vcom)electrode 6 then;

Then, after above-mentionedorganic insulator 5 and 6 formation of public (Vcom) electrode, on the surface oforganic insulator 5 and public (Vcom)electrode 6, utilize thin-film technique chemical vapor deposition passivation layer 7 (shown in the layout structure of Figure 15 and shown Figure 15 shown in Figure 16 at G-G ' position section sectional structure) again, wherein,passivation layer 7 is made by any material that comprises organic material or inorganic material;

Then, thepassivation layer 7 that covers on thecontact hole 8 is removed, plate the pixel electrode 101 (shown in Figure 17,18,19) that the layer of transparent conductive layer forms by sputtering technology onpassivation layer 7 again, described electrically conducting transparent layer material is for example tin indium oxide (ITO) or indium zinc oxide transparent materials such as (IZO);

At last, utilize photoetching process to form the pattern of pixel region, finish the making of this dot structure.

Spirit of the present invention is that theorganic insulator 5 of above-mentioned dot structure andsecond insulation course 4 are used to reduce formed stray capacitance betweendata signal line 3 and thepublic electrode 6, and utilizepublic electrode 6 andpixel electrode 101 to insert and putpassivation layer 7 as the required storage capacitors of pixel, utilize the opaqueness of the 3rd conductive metal layer to prevent light leak simultaneously, be responsible for the light of the inner unnecessary backlight module of blocking LCD, light source between each pixel can not interfered with each other, improve the contrast of display degree.

In sum as can be known, after present invention focuses on the second conductive metal layer patterning, successively on second conductive metal layer, be coated with first insulatinglayer 4 and one deckorganic insulator 5, public electrode (Vcom) 6 is made by the 3rd conductive metal layer then, this pixel design can reduce the stray capacitance ofdata signal line 3 and public electrode (Vcom) 6 bysecond insulation course 4 and one deckorganic insulator 5, to avoid producing crosstalk phenomenon, therefore the metal of public electrode (Vcom) 6 can be run line and cross overdata signal line 3, can improve aperture ratio of pixels by this design, reducing needs to strengthen the power attenuation that backlight module brightness consumed, thereby promotes product competitiveness.

The above is the preferred embodiments of the present invention only, is not to be used for limiting practical range of the present invention.Every equal variation and modification of being done in the present patent application claim includes in claim of the present invention.

Claims (20)

1. the pixel structure preparation method of a Thin Film Transistor-LCD comprises:

A) get a substrate;

B) with the first conductive metallic material film forming on described substrate surface forming first conductive metal layer, described first conductive metal layer forms the gate electrode of TFT structure and the scan signal line of pixel;

C) on the described first conducting metal laminar surface, form first insulation course and semiconductor layer;

D) described semiconductor layer is carried out composition, and form second conductive metal layer, described second conductive metal layer is carried out composition to form drain electrode, the source electrode of thin-film transistor structure in described semiconductor layer surface;

E) utilize thin-film technique on the described second conducting metal laminar surface, to form first insulating layer at least;

F) utilize thin-film technique to form the 3rd conductive metal layer, on the surface of described the 3rd conductive metal layer, form passivation layer then, and form contact hole at described second surface of insulating layer;

G) form the layer of transparent conductive layer, utilize composition technology to form the pattern of pixel electrode again, described pixel electrode is electrically connected with the source electrode of described thin-film transistor structure by described contact hole.

2. the pixel structure preparation method of Thin Film Transistor-LCD as claimed in claim 1, wherein, described substrate is made by hard material or softwood matter.

3. the pixel structure preparation method of Thin Film Transistor-LCD as claimed in claim 1, wherein, group or its combination in any that the described first conducting metal layer material uses molybdenum, tantalum, chromium, tungsten, aluminium and aluminium alloy to form perhaps also can be made multilayer according to demand.

4. the pixel structure preparation method of Thin Film Transistor-LCD as claimed in claim 1, wherein, the formation of described first insulation course and described semiconductor layer is to adopt electricity slurry assistant chemical vapor deposition device to carry out in a continuous manner.

5. the pixel structure preparation method of Thin Film Transistor-LCD as claimed in claim 4, wherein, described semiconductor layer comprises a-Si:H intrinsic layer and n+Si Ohmic contact film.

6. the pixel structure preparation method of Thin Film Transistor-LCD as claimed in claim 1, wherein, described second conductive metal layer forms data signal line.

7. the pixel structure preparation method of Thin Film Transistor-LCD as claimed in claim 1 wherein, can form one deck organic insulator at least at described second surface of insulating layer when carrying out thin-film technique.

8. the pixel structure preparation method of Thin Film Transistor-LCD as claimed in claim 1, wherein, described the 3rd conductive metal layer forms the pattern of the required public electrode of pixel.

9. the pixel structure preparation method of Thin Film Transistor-LCD as claimed in claim 1, wherein, described pixel electrode is material with the tin indium oxide.

10. the pixel structure preparation method of Thin Film Transistor-LCD as claimed in claim 1, wherein, described passivation layer is made by any one material that comprises organic material or inorganic material.

11. the dot structure of a Thin Film Transistor-LCD comprises:

Substrate;

First conductive metal layer is arranged on the described substrate surface;

First insulation course is positioned on described first conductive metal layer and the described substrate surface;

Semiconductor layer is arranged on described first surface of insulating layer;

Second conductive metal layer is arranged at described first insulation course, described semiconductor layer surface;

Second insulation course is arranged at the described second conducting metal laminar surface;

The 3rd conductive metal layer is arranged at described second surface of insulating layer;

Passivation layer is arranged at described second insulation course and described the 3rd conducting metal laminar surface;

Transparency conducting layer is arranged at described passivation layer surface;

Wherein, utilize the 3rd conductive metal layer and transparency conducting layer to insert and put described passivation layer as the required storage capacitors of pixel.

12. the dot structure of Thin Film Transistor-LCD as claimed in claim 11, wherein, described substrate is made by hard material or softwood matter.

13. the dot structure of Thin Film Transistor-LCD as claimed in claim 11, wherein, described first conductive metal layer is formed with the gate electrode of TFT structure and the scan signal line of pixel.

14. the dot structure of Thin Film Transistor-LCD as claimed in claim 11, wherein, group or its combination in any that the described first conducting metal layer material uses molybdenum, tantalum, chromium, tungsten, aluminium and aluminium alloy to form perhaps also can be made multilayer according to demand.

15. the dot structure of Thin Film Transistor-LCD as claimed in claim 11, wherein, described semiconductor comprises a-Si:H intrinsic layer and n+Si Ohmic contact film.

16. the dot structure of Thin Film Transistor-LCD as claimed in claim 11, wherein, described second conductive metal layer forms data signal line, drain electrode and source electrode.

17. the dot structure of Thin Film Transistor-LCD as claimed in claim 11 wherein, can form organic insulator on described second insulation course.

18. the dot structure of Thin Film Transistor-LCD as claimed in claim 11, wherein, described the 3rd conductive metal layer forms public electrode.

19. the dot structure of Thin Film Transistor-LCD as claimed in claim 11, wherein, described transparency conducting layer forms pixel electrode.

20. the dot structure of Thin Film Transistor-LCD as claimed in claim 11, wherein, described passivation layer is made by any material that comprises organic material or inorganic material.

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