US 2003/0190556 A1 · Method of manufacturing TFT array

Abstract

In the halftone region of a photomask, uniformity in thickness of the photoresist is enhanced. The halftone region of the photomask is arranged such that a transmitting portion and a shielding portion are alternately provided to form a transmitting/shielding pattern. The transmitting portion at the end of the transmitting/shielding pattern has a larger area than the other transmitting portion.

Drawings

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Drawings

Claims21

Dependent claims

A method of manufacturing a TFT array comprising the following steps of:

applying photoresist onto a film to be etched,
forming a photoresist pattern of desired pattern by exposing and developing the photoresist using a photomask,
etching the film using the photoresist pattern,
removing a part of the photoresist pattern, and
etching the film using the partly removed photoresist pattern,
wherein the photomask comprises;
a region A* in which illuminated light from an exposing machine during the exposure step is shade to limit the amount of illuminated light transmitting therethrough in order to leave the resist pattern through the step for partly removing the photoresist pattern,
a region C* in which illuminated light from the exposing machine during the exposure step is transmitted to allow the sufficient amount of illuminated light transmitting therethrough in order to remove the photoresist through the step of developing, and
a region B* in which a transmitting/shielding pattern having finer dimensions than resolution of the exposing machine is provided, so that the amount of light transmitting therethrough during the exposure step is intermediate between those in the region A* and C*, and
wherein the transmitting/shielding pattern has a ladder-like shape in which at least three rectangular transmitting portion, each of which has a predetermined length and width, are arranged in a lengthwise direction thereof, and a dimensional precision of the transmitting pattern is ±0.1 μm at maximum.

7 more elements

A method of manufacturing a TFT array comprising the following steps of:

applying photoresist onto a film to be etched,
forming a photoresist pattern of desired pattern by exposing and developing the photoresist using a photomask,
etching the film using the photoresist pattern,
removing a part of the photoresist pattern, and
etching the film using the partly removed photoresist pattern,
wherein the photomask comprises;
a region A* in which illuminated light from an exposing machine during the exposure step is shade to limit the amount of illuminated light transmitting therethrough in order to leave the resist pattern through the step for partly removing the photoresist pattern,
a region C* in which illuminated light from the exposing machine during the exposure step is transmitted to allow the sufficient amount of illuminated light transmitting therethrough in order to remove the photoresist through the step of developing, and
a region B* in which a transmitting/shielding pattern having finer dimensions than resolution of the exposing machine is provided, so that the amount of light transmitting therethrough during the exposure step is intermediate between those in the region A* and C*, and
wherein the transmitting/shielding pattern has a ladder-like shape in which at least three rectangular transmitting portion, each of which has a predetermined length and width, are arranged in a lengthwise direction thereof, and an area of the transmitting portion arranged at the end of the transmitting/shielding pattern is larger than that of the other transmitting portion.

7 more elements

A method of manufacturing a TFT array comprising the following steps of:

applying photoresist onto a film to be etched,
forming a photoresist pattern of desired pattern by exposing and developing the photoresist using a photomask,
etching the film using the photoresist pattern,
removing a part of the photoresist pattern, and
etching the film using the partly removed photoresist pattern,
wherein the photomask comprises;
a region A* in which illuminated light from an exposing machine during the exposure step is shade to limit the amount of illuminated light transmitting therethrough in order to leave the resist pattern through the step for partly removing the photoresist pattern,
a region C* in which illuminated light from the exposing machine during the exposure step is transmitted to allow the sufficient amount of illuminated light transmitting therethrough in order to remove the photoresist through the step of developing, and
a region B* in which a transmitting/shielding pattern having finer dimensions than resolution of the exposing machine is provided, so that the amount of light transmitting therethrough during the exposure step is intermediate between those in the region A* and C*, and
wherein the transmitting/shielding pattern has a stripes-like shape in which a transmitting portion and a shielding portion, having a predetermined width d and e over the length of the photomask respectively, are alternately arranged, and a dimensional precision of the transmitting portion is ±0.1 μm at maximum.

7 more elements

A method of manufacturing a TFT array comprising the following steps of:

applying photoresist onto a film to be etched,
forming a photoresist pattern of desired pattern by exposing and developing the photoresist using a photomask,
etching the film using the photoresist pattern,
removing a part of the photoresist pattern, and
etching the film using the partly removed photoresist pattern,
wherein the photomask comprises;
a region A* in which illuminated light from an exposing machine during the exposure step is shade to limit the amount of illuminated light transmitting therethrough in order to leave the resist pattern through the step for partly removing the photoresist pattern,
a region C* in which illuminated light from the exposing machine during the exposure step is transmitted to allow the sufficient amount of illuminated light transmitting therethrough in order to remove the photoresist through the step of developing, and
a region B* in which a transmitting/shielding pattern having finer dimensions than resolution of the exposing machine is provided, so that the amount of light transmitting therethrough during the exposure step is intermediate between those in the region A* and C*, and
wherein the transmitting/shielding pattern has a stripes-like shape in which a transmitting portion and a shielding portion, having a predetermined width d and e over the length of the photomask respectively, are alternately arranged, and a projection is provided by the end of the transmitting portion to enlarge the transmitting portion by the end.

7 more elements

Dependencies are inferred from the claim text.

Description9,055 words

Summary2,949 words

#The present invention relates to a method of manufacturing a TFT array of a liquid crystal display, and more particularly to a photomask to be used for exposing a photoresist to form a photoresist pattern.

#In a liquid crystal display, an electric field is applied to a liquid crystal held between opposed substrates, for carrying out display. A liquid crystal display has a lighter weight, smaller power consumption and greater portability than those of a CRT. In particular, an active matrix liquid crystal display (AMLCD), in which a switching element such as a thin film transistor (TFT) is provided on a substrate to control an electric field to be applied to a liquid crystal, is very excellent in quality of display and has recently been applied to wide uses.

#Referring to FIGS. 1 and 2, the active matrix liquid crystal display (AMLCD) will be described. FIG. 1 shows an example of circuit configuration in the AMLCD, which is referred to a so-called “Cs on Gate” AMLCD. The reference numeral 101 denotes a gate line for supplying a scanning signal, the reference numeral 102 denotes a source line for supplying a voltage signal, the reference numeral 103 denotes a thin film transistor (TFT) which is a switching element for applying a voltage to a liquid crystal, the reference numeral 104 denotes a liquid crystal for switching transmission/non-transmission of light which is represented as a capacitance on an equivalent circuit, the reference numeral 105 denotes a storage capacitance provided electrically in parallel with the liquid crystal 104 and serving to reduce the influence of a parasitic capacitance of a TFT, the reference numeral 106 denotes a connecting portion for connecting an electrode on either side of the liquid crystal 104 to a common voltage, the reference numeral 107 denotes a gate terminal for connecting an external circuit on the gate side to the gate line 101 through a TCP or the like, the reference numeral 108 denotes a source terminal for connecting an external circuit on the source side to the source line 102 through the TCP or the like, the reference numeral 111 denotes a line connected to the gate lines 101, the reference numeral 112 denotes a line connected to the source lines 102, and the reference numeral 113 denotes a connection for connecting the line 111 to the line 112. The reference numeral 114 denotes a repair line to be used when the source line is open. Although not shown in FIG. 1, a component which may be a TFT or an element of high resistance having linear or non linear characteristics may be provided between the gate terminal 107 and line 111 and between the source terminal 108 and line 112 to electrically isolate the gate terminal 107 and source terminal 108 during signal application and to electrically connect the gate terminal 107 and source terminal 108 when static electricity of high voltage invades. In many cases, a TFT array is formed with such a configuration as shown in FIG. 1 as described above. After combined with a counter substrate on which a color filter is provided, a liquid crystal is injected therebetween and the outside of a region 115 shown in a dotted line in the drawing is generally cut out to form a liquid crystal display.

Detailed description6,106 words

#An embodiment of the present invention will be described below with reference to the drawings.

#Embodiment 1

#The embodiment of the present invention will be described in detail with reference to FIGS. 10, 11 and 12.

Facts

Application

10/132,579Filed 3 Apr 2002

Published

9 Oct 2003

Term ends

Not estimatedThe source records don’t support an estimate.

Classification2 codes

G03F 1/50
Originals for photomechanical production of textured or patterned surfaces, e.g., masks, photo-masks, reticles; Mask blanks or pellicles…
G03F
Photomechanical production of textured or patterned surfaces

Timeline

3 Apr 2002Application filedUS 10/132,579
3 Apr 2002Assigned to Advanced Display Inc.assignment of assignor's interest
9 Oct 2003Published
26 Nov 2007Assigned to Mitsubishi Electric Corporationassignment of assignor's interest
15 Jul 2021Assigned to Trivale Technologiesassignment of assignor's interest

Method of manufacturing TFT array

Life of this patent

Method of manufacturing TFT array

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims21

Description9,055 words

Drawings

Classification2 codes

Life of this patent

Description9,055 words