U.S. patent application number 11/649238 was filed with the patent office on 2008-03-06 for thin film transistor array substrate and manufacturing method thereof.
This patent application is currently assigned to CHUNGHWA PICTURE TUBES, LTD. Invention is credited to Kuang-Cheng Fu, Jun-Yao Huang, Jen-Chieh Lin, Chin-Lung Yeh.
Application Number | 20080054264 11/649238 |
Document ID | / |
Family ID | 39150235 |
Filed Date | 2008-03-06 |
United States Patent
Application |
20080054264 |
Kind Code |
A1 |
Huang; Jun-Yao ; et
al. |
March 6, 2008 |
Thin film transistor array substrate and manufacturing method
thereof
Abstract
A thin film transistor array substrate and the manufacturing
method thereof are disclosed herein. A first patterned metal layer,
an insulating layer, a patterned layer, and a second patterned
metal layer are sequentially formed on a substrate. Then, a
plurality of scan lines and a plurality of source lines are
disposed on the substrate and define a plurality of pixel regions.
A plurality of the storage capacitance lines are disposed on the
substrate in a direction extending along the scan lines and across
the pixel regions, wherein each of the storage capacitance lines is
essentially perpendicular to each of the source lines and to form a
cross portion. A plurality of patterned thin films are disposed on
the storage capacitance lines and above the cross portion.
Inventors: |
Huang; Jun-Yao; (Padeh City,
TW) ; Fu; Kuang-Cheng; (Padeh City, TW) ; Lin;
Jen-Chieh; (Padeh City, TW) ; Yeh; Chin-Lung;
(Padeh City, TW) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Assignee: |
CHUNGHWA PICTURE TUBES, LTD
|
Family ID: |
39150235 |
Appl. No.: |
11/649238 |
Filed: |
January 4, 2007 |
Current U.S.
Class: |
257/59 ;
257/E27.113 |
Current CPC
Class: |
G02F 1/1345 20130101;
G02F 2201/50 20130101; H01L 27/1255 20130101; H01L 27/124 20130101;
G02F 1/136213 20130101; H01L 27/1244 20130101 |
Class at
Publication: |
257/59 |
International
Class: |
H01L 29/04 20060101
H01L029/04 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 5, 2006 |
TW |
95132726 |
Claims
1. A thin film transistor array substrate comprising: a substrate;
a plurality of scan lines and a plurality of source lines disposed
on the substrate, and define a plurality of pixel regions on the
substrate; a plurality of storage capacitance lines disposed on the
substrate in a direction extending along the scan lines and across
the pixel regions, each of the storage capacitance lines is
essentially perpendicular to each of the source lines and to form a
cross portion; and a plurality of patterned thin films disposed on
the storage capacitance lines and above the cross portion.
2. The thin film transistor array substrate according to claim 1,
further comprising an insulating layer disposed on the scan lines
and the storage capacitance lines.
3. The thin film transistor array substrate according to claim 2,
wherein the patterned thin films are disposed on the insulating
layer.
4. The thin film transistor array substrate according to claim 1,
wherein the patterned thin films are further disposed on the scan
lines and above a cross portion of the scan lines and the source
lines.
5. The thin film transistor array substrate according to claim 1,
wherein each of the pixel regions comprises a pixel electrode.
6. The thin film transistor array substrate according to claim 5,
wherein each of the pixel regions further comprises a transistor
electrically connected with the pixel electrode.
7. A manufacturing method of a thin film transistor array
substrate, comprising: forming a first patterned metal layer on a
substrate to define a plurality of scan lines and a plurality of
storage capacitance lines, the storage capacitance lines disposed
in a direction extending along the scan lines; forming an
insulating layer on the first patterned metal layer; forming a
second patterned metal layer to define a plurality of source lines,
the source lines and the scan line define a plurality of pixel
regions, and each of the storage capacitance lines is essentially
perpendicular to each of the source lines and to form a cross
portion; and forming a patterned layer on the insulating layer to
define a plurality of patterned thin films disposed on the storage
capacitance lines and above the cross portion.
8. The manufacturing method of a thin film transistor array
substrate according to claim 7, further comprising the step of
forming a plurality of pixel electrodes in the pixel regions.
9. The manufacturing method of a thin film transistor array
substrate according to claim 8, further comprising the step of
forming a plurality of transistors in the pixel regions to
electrically connect with the pixel electrodes.
10. The manufacturing method of a thin film transistor array
substrate according to claim 9, further comprising the step of
forming each source electrode and each drain electrode of the
transistors at the second patterned metal layer.
11. The manufacturing method of a thin film transistor array
substrate according to claim 9, further comprising the step of
forming an ohmic contact thin film for each of the transistors at
the patterned layer.
12. The manufacturing method of a thin film transistor array
substrate according to claim 7, further comprising the step of
forming the patterned thin films on the scan lines at a cross
portion of the scan lines and the source lines to cover the cross
portion.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention generally relates to a liquid crystal
display device, and more particularly relates to a thin film
transistor (TFT) array substrate for the liquid crystal display
device and the manufacturing method thereof.
[0003] 2. Description of the Prior Art
[0004] FIG. 1 is illustrated a plan view of the liquid crystal
display according to the prior art. Referring to FIG. 1, scan lines
102 and source lines 109 are disposed to cross to define a
plurality of pixel regions. The storage capacitance line (Cs line)
104 is extended over the pixel region to cross the source line 109.
An ohmic contact thin film 106, a source electrode 110 and a drain
electrode 111 are disposed on the scan line 102. Besides, a pixel
electrode 114 is disposed in the pixel region. Wherein, scan lines
102 and the Cs lines 104 are simultaneously formed and there is an
insulating layer, not shown in the figure, covered thereon. The Cs
line 104 is electrically isolated by the insulating layer and is
under crossing the source line 109.
[0005] Due to the fact that the complex metal is used, it is
difficult to control a good profile of the taper angle because of
the etching rate of different materials so as to easily cause the
undercut effect. Such as shown in FIG. 2, it is the sectional view
of the A-A' cross-section of FIG. 1 at the cross portion of the
source line 109 and the storage capacitance line 104, the undercut
effect presents at the Cs line 104 of the first metal layer
arranged on a substrate 100. An insulating layer 103 is formed on
the Cs line 104 of the first metal layer and then a source line 109
of a second metal layer is formed on the Cs line 104 of the first
metal layer. Because of the undercut effect of the first metal
layer, it easily causes the rip of the insulating layer 103 so as
to occur the short of the source line 109 and the Cs line 104. This
defect will cause the light line of the liquid crystal display
device while turning on the panel and this panel must perform the
array test to find the defect and perform the laser repair.
Further, the panel is scrapping. Hence, how to overcome the
mentioned problem is important for enhancing the yield of the LCD
panel.
SUMMARY OF THE INVENTION
[0006] In order to solve the mentioned problem, one object of the
present invention is to provide a thin film transistor array
substrate and the manufacturing method thereof. It utilizes a
patterned thin film disposed at the cross portion of the source
lines and the Cs lines and between two layers so as to solve the
short problem at the cross portion.
[0007] Another object of the present invention is to provide a thin
film transistor array substrate and the manufacturing method
thereof. It only needs to add a pattern in the second photo-mask to
dispose a plurality of patterned thin films at the cross portion of
the source lines and the Cs lines without using the extra
photo-mask in the process and effectively prevent the short problem
causing from the rip of the insulating layer at the cross portion
of the source lines and the Cs lines.
[0008] Further object of the present invention is to provide a thin
film transistor array substrate and the manufacturing method
thereof. The structure of the cross portion of the source lines and
the Cs lines is improved to effectively enhance the yield rate of
the product and can apply to the liquid crystal display device with
all kinds of size.
[0009] The other object of the present invention is to provide a
thin film transistor array substrate and the manufacturing method
thereof. It utilizes a patterned thin film arranged at the cross
portion of source lines and scan lines and between two layers so as
to solve the short problem between source lines and scan lines.
[0010] Furthermore object of the present invention is to provide a
thin film transistor array substrate and the manufacturing method
thereof. It can reduce the frequency for the laser repair and the
array testing time to effectively control the product yield without
changing the process conditions.
[0011] Accordingly, one embodiment of the present invention
provides a thin film transistor array substrate including: a
substrate; a plurality of scan lines and a plurality of source
lines disposed on the substrate, and define a plurality of pixel
regions on the substrate; a plurality of storage capacitance lines
disposed on the substrate in a direction extending along the scan
lines and across the pixel regions, each of the storage capacitance
lines is essentially perpendicular to each of the source lines and
to form a cross portion; and a plurality of patterned thin films
disposed on those storage capacitance lines and above the cross
portion.
[0012] Another embodiment of the present invention provides a
manufacturing method of a thin film transistor array substrate. The
manufacturing method includes: forming a first patterned metal
layer on a substrate to define a plurality of scan lines and a
plurality of storage capacitance lines, the storage capacitance
lines disposed in a direction extending along the scan lines;
forming an insulating layer on the first patterned metal layer;
forming a second patterned metal layer to define a plurality of
source lines, the source lines and the scan line define a plurality
of pixel regions, and each of the storage capacitance lines is
essentially perpendicular to each of the source lines and to form a
cross portion; and forming a patterned layer on the insulating
layer to define a plurality of patterned thin films disposed on the
storage capacitance lines and above the cross portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The foregoing aspects and many of the accompanying
advantages of this invention will become more readily appreciated
as the same becomes better understood by reference to the following
detailed description, when taken in conjunction with the
accompanying drawings, wherein:
[0014] FIG. 1 is the plan view of the liquid crystal display
according to the prior art;
[0015] FIG. 2 is the sectional view of A-A' cross-section of FIG. 1
according to the prior art;
[0016] FIG. 3 is the plan view of the thin film transistor array
substrate according to one embodiment of the present invention;
and
[0017] FIG. 4 is the sectional view of B-B' cross-section of FIG. 3
according to one embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0018] FIG. 3 is a plan view of the thin film transistor array
substrate illustrated one embodiment of the present invention. Such
as shown in FIG. 3, in the present embodiment, a thin film
transistor (TFT) array substrate includes a plurality of scan lines
202 and a plurality of source lines 209 disposed on the substrate
and define a plurality of pixel regions. A plurality of storage
capacitance lines (Cs line) 204 are disposed on the substrate in a
direction extending along to across the pixel regions, and each of
Cs lines 204 is essentially perpendicular to each of the source
lines 209 to form a cross portion. A plurality of patterned thin
films 208 are disposed on Cs lines 204 and above the cross
portion.
[0019] Following the foregoing, in the present embodiment, the scan
lines 202 and the Cs lines 204 are simultaneously formed in the
same process. After, an insulating layer (not shown FIG. 3) is
disposed to cover the scan lines 202 and the Cs lines 204. Wherein,
the patterned thin films 208 are disposed on the insulating layer.
Further, at the cross portion of the scan lines 202 and the source
lines 209, the patterned thin film 208' could be disposed on the
scan lines 202 at the cross portion and between two layers to cover
the cross portion. In the present embodiment, each of the pixel
regions comprises a pixel electrode 214 disposed on Cs lines 204 in
the pixel regions and each of the pixel regions further comprises a
transistor electrically connected with the pixel electrode.
Further, as simultaneously forming patterned thin film 208 and the
patterned thin film 208', an ohmic contact thin film 206 for the
transistor is simultaneously formed. Besides, a source electrode
210 and a drain electrode 211 are simultaneously formed with the
source lines 209.
[0020] In one embodiment, the manufacturing method of TFT array
substrate is sequentially forming a first patterned metal layer, an
insulating layer, a patterned layer and a second patterned metal
layer on a substrate. The first patterned metal layer is defined
the scan lines and the Cs lines, and the second patterned metal
layer is defined source lines. The description of the further
layout of the pixel of the TFT array substrate is the same as the
mentioned above.
[0021] FIG. 4 is the sectional view of B-B' cross-section of FIG. 3
illustrated the cross portion of the source lines 209 and the Cs
lines 204 and the cross portion of the source lines 209 and the
scan lines 202. Following the foregoing and referring to FIG. 4, at
the cross portion of the source lines 209 and the Cs lines 204, a
Cs line 204, an insulating layer 203, a plurality of patterned thin
films 208 and a source line 209 are respectively disposed on a
substrate 200. Such as shown in FIG. 4, the patterned thin films
208 are disposed on the Cs line 204 and above the cross portion of
the source lines 209 and the Cs lines 204. Hence, even the metal
layer of the Cs line 204 provided with a bad profile of the taper
angle to produce the undercut effect to cause the rip of the
insulating layer 203, because of the protection from the patterned
thin films 208, it prevents the short problem of the source lines
209 and the Cs lines 204.
[0022] Referring to FIG. 3 and FIG. 4, in one embodiment, the
manufacturing method of a TFT array substrate for a liquid crystal
display device includes the following steps. First, a first
patterned metal layer is formed on a substrate 200 to define a
plurality of scan lines 202 and a plurality of Cs lines 204 on the
substrate. Wherein, the Cs lines 204 are disposed along the scan
lines 202. Then, an insulating layer 203 is formed on the first
patterned metal layer. Next, a second patterned metal layer is
formed to define a plurality of source lines 209 to cross the scan
lines 202 so as to define a plurality of pixel regions. Wherein,
the second patterned metal layer further defines a plurality of
source electrodes 210 and a plurality of drain electrodes 211.
Besides, the Cs lines 204 are disposed to extend over the pixel
regions and to cross under the source lines 209. After, a patterned
layer 207 is formed on the insulating layer 203 to define a
plurality of patterned thin films 208 disposed on the Cs lines 204
at the cross portion of the Cs lines 204 and the source lines 209
to cover the cross portion. In one embodiment, the patterned layer
207 is a semiconductor layer. A plurality of pixel electrodes 214
are disposed on the Cs lines 204 in the pixel regions and a
plurality of transistors are respectively disposed on the scan
lines 202 in pixel region and electrically connect with the pixel
electrodes. Further, the patterned layer 207 is also defined an
ohmic contact thin film 206 of those transistor and a plurality of
patterned thin film 208' disposed on the scan lines 202 and above
the cross portion of the scan lines 202 and the source lines 209 to
cover the cross portion. In the present embodiment, it can utilize
the photolithography process to form the patterned films or
materials on the substrate. For example, after depositing the
transparent conductive layer, it can utilize the photolithography
process to define the pixel electrode.
[0023] Accordingly, one of features is to utilize the layer
originally formed between the first patterned metal layer and the
second patterned metal layer of the TFT array substrate, except for
the insulating layer, to further improve the isolation at the cross
portion therebetween. The original layer is further disposed a
patterned thin film on the insulating layer on the Cs line at the
cross portion of the source line and the Cs line to provide the
isolation and to prevent the short problem at the cross portion.
Such as shown in FIG. 3, the patterned thin films 208, patterned
thin films 208' and the ohmic contact thin film 206 are linked. It
could be understood that the patterned thin films 208' and the
ohmic contact thin film 206 could be respectively isolated
patterns.
[0024] To sum up the forgoing, the present invention utilizes a
patterned thin film disposed on the Cs lines at the cross portion
of the source lines and the Cs lines and between two layers to
completely solve the short problem at the cross portion. The
present prevents the short problem causing from the rip of the
insulating layer at the cross portion by adding a pattern in the
second photo-mask to arrange a plurality of patterned thin films at
the cross portion without using the extra photo-mask in the
process. The structure of the cross portion of the source lines and
the Cs lines is improved to effectively control and enhance the
yield of the product without changing process conditions and can
apply to the liquid crystal display device with all kinds of size
and can reduce the frequency for the laser repair and the array
test time.
[0025] While the present invention is susceptible to various
modifications and alternative forms, a specific example thereof has
been shown in the drawings and is herein described in detail. It
should be understood, however, that the invention is not to be
limited to the particular form disclosed, but to the contrary, the
invention is to cover all modifications, equivalents, and
alternatives falling within the spirit and scope of the appended
claims.
* * * * *