JP3616584B2 - Pattern forming method and display device manufacturing method using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pattern forming method for a semiconductor device such as a thin film transistor and a method for manufacturing a display device using the same, and more particularly to a pattern forming method using a resist reflow technique and a thin film transistor substrate for a display device using the pattern forming method. Regarding the method.
[0002]
[Prior art]
High integration of semiconductor devices has been achieved with the support of photolithography technology and dry etching technology, which are means for forming fine patterns. However, when the performance of the semiconductor device is improved in this way, the manufacturing process is advanced and the manufacturing cost is increased.
[0003]
Therefore, recently, (1) forward taper of the wiring pattern, which is one of the sophistication of the process, and (2) the whole process by integrating the pattern manufacturing process in order to greatly reduce the manufacturing cost of the semiconductor device. There has been a strong demand to reduce the number.
[0004]
In the conventional technique, the conventional wiring formation (hereinafter referred to as the first conventional example) for the forward taper and the known example wiring formation (hereinafter referred to as the second conventional example). Will be described with reference to the drawings.
[0005]
FIG. 25 is a schematic cross-sectional view in order of the manufacturing process of the wiring pattern for explaining the first conventional example.
[0006]
As shown in FIG. 25A, for example, a metal film 402 such as an aluminum alloy is formed on an insulating substrate 401 such as a glass substrate. Here, the film thickness of the metal film 402 is about 1 μm. Then, a resist mask 407 is formed in a predetermined region on the metal film 402 by a known photolithography technique.
[0007]
Next, as shown in FIG. 25B, the resist mask 407 is used as an etching mask, and the metal film 402 is subjected to the first etching, so that the first forward taper layer 415 is formed.
[0008]
Next, as shown in FIG. 25C, the entire resist mask 407 undergoes thermal reflow by being heat-treated at 150 to 200 ° C., hangs down horizontally, and becomes a thermal reflow resist mask 413.
[0009]
Next, as shown in FIG. 25D, the remaining metal film 402 is subjected to the second etching using the thermal reflow resist mask 413 as an etching mask, and the second forward taper layer 416 is formed in the lower layer. 411 is formed.
[0010]
FIG. 26 is a schematic cross-sectional view showing the manufacturing method of the second conventional example (Japanese Patent Application No. 2000-133636) in the order of the manufacturing steps.
[0011]
As shown in FIG. 26A, for example, a metal film 422 such as an aluminum alloy is formed on the insulating substrate 421. Here, the film thickness of the metal film 422 is about 1 μm. Then, a resist mask 427 is formed in a predetermined region on the metal film 422 by a known photolithography technique.
[0012]
Next, as shown in FIG. 26B, the resist mask 427 is used as an etching mask, and the first etching is performed on the metal film 422 to form the first forward tapered layer 435.
[0013]
Next, after the formation of the first forward tapered layer 435 shown in FIG. 26B, the resist mask 427 is immersed in an organosilane solution that is a silylating agent together with the insulating substrate 421. Alternatively, the resist mask 427 is exposed to organosilane vapor. In this way, the resist mask 427 is silylated.
[0014]
By this silylation treatment, the resist mask 427 expands in volume, and an expanded silylated resist mask 433 is formed as shown in FIG. Due to this silylation, the pattern width of the expanded silylated resist mask 433 becomes larger than the pattern width of the resist mask 427 indicated by a broken line in the drawing. Here, silazane or the like is used as the silylating agent.
[0015]
Next, the expanded silylated resist mask 433 is used as an etching mask, and the remaining metal film 422 is subjected to the second etching to form the wiring 431 having the second forward tapered layer 436 in the lower layer. . However, since the adhesive force of the expanded silylated resist mask 433 is weak, the lower portion of the first forward taper layer 435 is side-etched, and an irregularly shaped side-etched portion 432 is formed in the first forward taper layer 435. There was a case. In this way, the wiring 431 is formed.
[0016]
In addition, among the conventional techniques, in the case of the current overlapping wiring formation (hereinafter referred to as a third conventional example) that causes the request to be made in response to the request to shorten the manufacturing process, and A case of wiring formation (hereinafter referred to as a fourth conventional example) in which the process has been shortened in response to the request will be described with reference to the drawings.
[0017]
FIG. 27 is a schematic cross-sectional view of a part of the manufacturing process of the inverted staggered TFT for explaining the third conventional example.
[0018]
As shown in FIG. 27A, a gate electrode 442 is formed on an insulating substrate 441 made of a transparent substrate such as glass, and a gate insulating film 443, an amorphous silicon (a-Si) film 444, and an n + type amorphous silicon (n + A type a-Si) film 445 and a metal film 446 are stacked and deposited, and first resist masks 447 and 448 are formed on the metal film 446 by a known photolithography technique.
[0019]
Next, as shown in FIG. 27B, the first resist masks 447 and 448 are used as etching masks, and the metal film 446 and the n + type a-Si film 445 are dry-etched.
[0020]
In this manner, the source electrode 451 and the ohmic contact layer 449 for the source electrode, the drain electrode 452 and the ohmic contact layer 450 for the drain electrode are formed. Thereafter, the first-time formed resist masks 447 and 448 are peeled and removed.
[0021]
Next, as shown in FIG. 27C, the source electrode 451, the ohmic contact layer 449, the drain electrode 452, and the ohmic contact layer 450 are covered so that a part of the surface of the a-Si film 444 is covered. A second resist mask 453 is formed by a known photolithography technique.
[0022]
Next, the a-Si film 444 is etched using the second resist mask 453 as an etching mask, whereby an island layer 454 is formed. Then, the second resist mask 453 is peeled and removed.
[0023]
In this way, an inverted staggered TFT is formed. Although description of subsequent steps is omitted, as an example, a pixel electrode, a passivation insulating film, and the like are formed, and an active matrix TFT-LCD element is formed.
[0024]
FIG. 28 is a schematic cross-sectional view of a part of the manufacturing process of the inverted staggered TFT for explaining the fourth conventional example disclosed in Japanese Patent Laid-Open No. 2000-133636. Here, FIG. 28A is the same as FIGS. 27A and 27B described in the third conventional example.
[0025]
Next, resist masks 467 and 468 are immersed in the organosilane solution. Alternatively, it is exposed to organosilane vapor. In this way, the resist masks 467 and 468 are silylated. By this silylation treatment, the resist masks 467 and 468 are volume-expanded and merged as shown in FIG. 28B to form one expanded silylated resist mask 473. In the expansion in this case, the dimensions of the resist masks 467 and 468 indicated by broken lines in the drawing cause a volume expansion of 0.1 to 2.0 μm.
[0026]
Next, the expanded silylated resist mask 473 is used as an etching mask to perform second etching, and the a-Si film 464 is etched.
[0027]
In this way, an island layer 474 is formed as shown in FIG. Thereafter, the expanded silylated resist mask 473 is peeled and removed.
[0028]
In this way, an inverted staggered TFT is formed. Although description of subsequent steps is omitted, as an example, a pixel electrode, a passivation insulating film, and the like are formed, and an active matrix TFT-LCD element is formed.
[0029]
FIG. 29 is a schematic cross-sectional view of a part of the manufacturing process of the inverted staggered TFT for explaining the fifth conventional example disclosed in Japanese Patent Laid-Open No. 2000-131719. Here, FIG. 29A is the same as FIGS. 27A and 27B described in the third conventional example.
[0030]
Next, as in the first conventional example, the resist masks 487 and 488 are subjected to thermal reflow by heat treatment at 150 to 250 ° C., and sag laterally to form thermal reflow resist masks 493 and 494. In this case, when the distance L between the channels is 0.1 to 2.0 μm, it can be combined by taking a long processing time, but because the reflow has a high viscosity, which is a drawback of thermal reflow, the tip is FIG. 29 (b) shows that the reflowing is uneven and reflowing, the resist coalescence tends to be incomplete, and thermal reflowing exceeding 2.0 μm is almost impossible even if the processing time is greatly increased. As described above, there are cases where the thermal reflow resist masks 493 and 494 are not completely combined. Also, when the a-Si film 484 in the lower layer is etched in this state due to insufficient coalescence of the resist mask and poor adhesion with the lower layer film, as shown in FIG. The combined island layer is not formed, and the separated island layers 495 and 496 are formed, and the TFT channel portion is not normally formed.
[0031]
In this way, an inverted staggered TFT is formed. Although description of subsequent steps is omitted, as an example, an active matrix TFT-LCD element is formed by forming a pixel electrode, a passivation insulating film, etc., but the TFT element by thermal reflow of the fifth conventional example The distance L between the channels that can form the film is limited to 0.1 to 2.0 μm or less.
[0032]
[Problems to be solved by the invention]
In the case of the first conventional example of FIG. 25 for the forward taper of the wiring pattern (1) among the conventional techniques described above, in the thermal reflow by the heat treatment of the resist mask 407, the components in the resist together with the reflow. Since evaporation of the water is promoted, the volume shrinks. Further, the lateral expansion of the resist mask 407 is limited to about 0.5 to 2.0 μm, and the thermal reflow is a non-uniform reflow with a wavy tip due to the high viscosity reflow. As a result, side etching is likely to occur, and insufficiently tapered wiring, that is, the cross section of the wiring easily becomes vertical or partially reverse tapered.
[0033]
The above-described second conventional example eliminates the above-described disadvantages of the first conventional example by utilizing the volume expansion of the resist. In that respect, a great effect is obtained. However, as a result of further experiments by the inventors, if the expansion is too large, the adhesion between the expanded resist and the underlying film (film to be etched) underneath is weakened, and as a result, side etching may occur. Then found. In the experiment, we have obtained the result that there is no problem even if the resist is expanded in the lateral direction up to 0.1 to 2.0 μm using volume expansion. Then, it is necessary to consider the above-mentioned problem.
[0034]
Next, in the third prior art example of FIG. 27 for shortening the total number of processes by short-circuiting the pattern manufacturing process in order to significantly reduce the manufacturing cost of the semiconductor device (2) among the conventional techniques. In the manufacture of a staggered TFT, the source electrode 451, the ohmic contact layer 449 and drain electrode 452 for the source electrode, the ohmic contact layer 450 for the drain electrode, and the island layer 454 are formed twice for photolithography. There was a problem that a process was required.
[0035]
The above-described fourth conventional example uses the same principle as the first conventional example. In the case of the fourth conventional example, the distance between the source and drain electrodes of the TFT element portion is 0.1 to 2.0 μm. If it is possible only by the following and becomes 4 μm or more, there is a problem that it is practically difficult to combine the resist masks for the reasons described above.
[0036]
The fifth conventional example described above also uses the same principle as the second conventional example 1. In the fifth conventional example, the processing time is reduced until the distance between the channels is 0.1 to 2.0 μm. It can be merged by taking a long time, but due to the high viscosity reflow which is a drawback of thermal reflow, it becomes uneven reflow with a wavy tip, and the resist coalescence tends to be incomplete, and more than 2.0 μm Thermal reflow itself is almost impossible even if the processing time is significantly increased, and may not be completely combined. Moreover, due to insufficient coalescence of the resist mask and poor adhesion to the lower layer film, the coalesced island layer is not formed and becomes a separated island layer, and the TFT channel portion is not normally formed.
[0037]
Therefore, the distance of the channel portion where the TFT element can be formed by thermal reflow of the fifth conventional example is limited to 0.1 to 2.0 μm or less, and the TFT element is often incomplete. There's a problem.
[0038]
SUMMARY OF THE INVENTION An object of the present invention is to provide a pattern forming method capable of forming a pattern having a different pattern size, which conventionally requires 2PR, with 1PR.
[0039]
[Means for Solving the Problems]
In view of the above-described problems, the present invention allows a chemical solution that dissolves a resist organic film to permeate the resist organic film, dissolves the resist organic film with the chemical solution, and reflows (referred to as chemical solution reflow, dissolution reflow, or chemical solution reflow). It is.
[0040]
That is, in a pattern forming method, a film to be etched is formed into a desired pattern using an etching process. After a resist film is formed on the film to be etched, the resist film is patterned using a first mask, and then the first mask is formed. The film to be etched is etched using the mask, then the first mask is reflowed with a chemical solution to form a second mask, and then the etching is continued using the second mask.
[0041]
Here, one layer may be entirely etched by the first etching, and a different layer below may be etched by the second etching, or one layer may be etched halfway by the first etching and then the second etching. Etching of this layer may also be performed.
[0042]
By the above-mentioned method, the above-mentioned problem is solved. That is, in the conventional example 2, only the volume expansion of the resist is used, so that there is a problem of the adhesion force of the etching target layer in contact with the resist. In the present invention, since the reflow is used, the above-described conventional example 2 is used. This problem is also solved. Hereinafter, specific embodiments will be described with reference to the drawings.
[0043]
The pattern forming method of the present invention includes a step of forming an organic film having a predetermined pattern on an etching target film, a part of the etching target film is removed from the surface using the organic film as a mask, and the etching target film A step of forming a film into an exposed region and a covering region covered with the organic film, a step of deforming the organic film into a deformed organic film extending to the exposed region, and the deformed organic film as a mask. Etching the exposed region of the film to be etched, wherein the step of forming the deformed organic film comprises infiltrating the organic film with an organic solvent solution and dissolving the organic film. The basic configuration is that it is performed by dissolution reflow to be generated.
[0044]
The organic film is an organic film mainly composed of an organic material and an organic solvent, and an organic film mainly composed of an inorganic material and an organic solvent. The former organic material is a resist film, a resin such as acrylic, polyimide, polyacrylamide and the like, and a polymer organic material. As the latter inorganic material, siloxane or polysiloxane, polysilane, polysilene, carbosilane, silicon, inorganic glass As the organic solvent used for both, all of the organic solvent chemicals described above can be used, and among them, an organic film using an appropriate organic solvent is used.
[0045]
When the organic film is a water-soluble material, the water-soluble material is polyacrylic acid, polyvinyl acetal, polyvinyl pyrrolidone, polyvinyl alcohol, polyethylene imine, polyethylene oxide, styrene-maleic anhydride copolymer, polyvinyl amine, One of polyallylamine, oxazoline group-containing water-soluble resin, water-soluble melamine resin, water-soluble urea resin, alkyd resin, sulfonamide, a mixture of two or more of these, or a material mainly composed of these salts Or an organic film using any one of materials obtained by mixing inorganic materials with the materials described above.
[0046]
When the organic film is mainly composed of an organic material or an inorganic material that is soluble in an organic solvent, a solution of the organic solvent is used as the chemical solution, and the organic solvent and the organic material that are soluble in water, or organic When mainly composed of a solvent and an inorganic material, it is possible to cause the same treatment effect by using an aqueous solution containing at least water as a chemical solution.
[0047]
In the following, particularly when the organic film is composed of an organic material soluble in an organic solvent, a solution of the organic solvent is used as the chemical solution, and the first reflow method described above as the reflow method, that is, exposure to the chemical vapor. An example using the reflow method is shown. However, as described above, the organic film is mainly composed of an inorganic material and an organic solvent, an organic film mainly composed of a water-soluble material, and a mixture of a water-soluble material and an inorganic material. It can also be used as a material, and as the reflow method, a second reflow method, that is, a reflow method of immersing in a chemical solution can be used. The pattern forming method of the basic configuration of the present invention adopts various application forms as follows.
[0048]
First, in the step of forming the organic film, an adjacent organic film adjacent to the organic film is formed. In the step of forming the deformed organic film, the adjacent organic film becomes an adjacent deformed organic film, and the modified organic film Combines with the membrane.
[0049]
A step of removing a part of the deformed organic film between the step of forming the deformed organic film and the step of etching the exposed region of the film to be etched; The removing step is performed by performing an ashing process using oxygen or an ozone process using ultraviolet rays on the deformed organic film to reduce the area of the deformed organic film.
[0050]
The steps from the step of forming the deformed organic film to the step of etching the exposed region of the film to be etched are repeated at least once after the step of etching the exposed region of the film to be etched.
[0051]
Of the etching of the film to be etched, at least the last etching is performed by wet etching.
[0052]
The organic solvent solution contains at least one of the following organic solvents. Organic solvent (R represents an alkyl group or a substituted alkyl group, Ar represents a phenyl group or an aromatic ring other than a phenyl group):
・ Alcohols (R-OH)
・ Alkoxy alcohols
Ethers (R—O—R, Ar—O—R, Ar—O—Ar)
・ Esters
・ Ketones
・ Glycols
・ Alkylene glycols
・ Glycol ethers
In addition, the dissolution reflow is performed by exposing to the vapor of the organic solvent solution or by immersing in the organic solvent solution.
[0053]
Further, the organic film is composed of a plurality of organic films having different film thicknesses, and when the organic film is a photosensitive organic film, the plurality of organic films having different film thicknesses has an exposure amount to the photosensitive organic film. Specifically, the organic film is composed of a plurality of organic films having different film thicknesses, and the film to be etched is partially removed from the surface using the organic film as a mask. Etching the organic film between a step of forming an exposed region and a covered region covered with the organic film, and a step of deforming the organic film to form a deformed organic film extending to the exposed region. Removing a relatively thin organic film from a plurality of organic films having different film thicknesses constituting the organic film, leaving a thicker organic film than the relatively thin organic film More specifically, the organic film is masked. Removing a part of the film to be etched from the surface as a mask, forming the film to be etched into an exposed region and a covering region covered with the organic film, and deforming the organic film to the exposed region. A step of removing the altered layer on the surface of the organic film is performed during the process of forming the extended deformed organic film. Further, the step of removing the altered layer on the surface of the organic film is performed by subjecting the organic film to plasma treatment or UV ozone treatment, and the plasma treatment is performed using a plasma processing gas containing O 2 gas, a fluorine-based gas. Plasma treatment is performed using any one of a plasma processing gas including a gas and a plasma processing gas including a mixed gas of O 2 gas and a fluorine-based gas, and the plasma processing gas includes a fluorine-based gas. SF ₆ , CF ₄ , CHF ₃ When the plasma processing gas is a plasma processing gas containing a mixed gas of O 2 gas and fluorine-based gas, SF is used. ₆ / O ₂ , CF ₄ / O ₂ , CHF ₃ / O ₂ Including any gas.
[0054]
A step of partially removing the film to be etched from the surface using the organic film as a mask to make the film to be etched an exposed region and a coating region covered with the organic film; and deforming the organic film. Then, a step of immersing the film to be etched and the organic film in a hydrofluoric acid solution is performed during the step of forming the deformed organic film extending to the exposed region.
[0055]
The film to be etched includes a first film and a second film in order from the bottom, the second film is removed by etching using the organic film as a mask, and the first film is removed from the deformed organic film. Etching away as a mask, the first film is a first metal film, and the second film is a second metal film made of a material different from the first metal film, or The first film is a silicon film, and the second film is an ohmic contact silicon film and a metal film containing high-concentration impurities in order from the bottom. Alternatively, the first film is a silicon film in order from the bottom. And the second film is a metal film. In the latter two cases, the silicon film constitutes a semiconductor layer of a thin film transistor, and the silicon film for the ohmic contact. The film and the metal film constitute a source electrode and a drain electrode of a thin film transistor, and when the organic film is composed of an organic film having a plurality of thicknesses, the organic film is thickly formed on the channel side of the semiconductor layer. A thin film organic film formed thin on the side of the semiconductor layer away from the channel, and after forming the source electrode and the drain electrode of the thin film transistor, the organic film is etched from the surface to Only the thick organic film is left on the source electrode and the drain electrode, and the thick organic film is deformed to form a deformed organic film.
[0056]
A photoresist film is suitable as the organic film in the pattern forming method of the present invention.
[0057]
As a material of the resist mask used here, the following organic resist is preferable. For example, as a material formed from a polymer compound, a photosensitizer, and other additives, there are a resist composed only of an organic material and a resist composed of a mixture of an organic material and an inorganic material.
[0058]
In a resist composed only of an organic material, there is polyvinyl cinnamate as an example of polyvinyl. Examples of rubber-based materials include those obtained by mixing a bisazide compound with cyclized polyisoprene or cyclized polybutadiene. An example of a novolac resin system is a mixture of a cresol novolac resin and naphthoquinonediazide-5-sulfonic acid ester. Examples of acrylic resin copolymer resins include polyacrylamide and polyamic acid. As another example, there is a resist to which bromine or iodine is added or contains a large amount.
[0059]
On the other hand, as a resist made of an organic material and an inorganic material, there is a siloxane as an example of a Si-containing resist or a resist containing polysiloxane, polysilane, polysilene, or carbosilane, and germanium is included as an example of a metal-containing resist other than Si. There is a resist.
[0060]
The resist mask may be formed of either a negative type resist or a positive type resist. As the positive type, a novolac resin-based material, for example, a mixture of cresol novolac resin and naphthoquinonediazide-5-sulfonic acid ester is suitable. As the negative type, rubber-based materials such as cyclized polyisoprene or cyclized polybutadiene mixed with a bisazide compound are suitable.
[0061]
The pattern forming method of the present invention is suitable for a method of manufacturing an active matrix substrate such as a TFT substrate constituting a display device such as a liquid crystal display device or an EL display device. That is, in a manufacturing method of a TFT substrate for a display device, a step of forming a gate electrode on the substrate, a step of sequentially forming a gate insulating film, a semiconductor layer, and a metal layer so as to cover the gate electrode, and patterning the metal layer Forming a mask for forming the source electrode and the drain electrode and reflowing the mask by dissolving the mask by infiltrating the organic solvent into the mask after patterning the metal layer, A method for manufacturing a TFT substrate is provided, which includes a step of connecting a mask located between the steps and a step of patterning a semiconductor layer using the connection mask obtained by the step of connecting the mask. Such a method for manufacturing a TFT substrate for a display device further includes a step of forming an ohmic layer between the metal layer and the semiconductor layer, and the ohmic layer is also patterned in the patterning step of the metal layer. The method for manufacturing a TFT substrate for a display device includes a step of forming an ohmic layer between the metal layer and the semiconductor layer, the ohmic layer is also patterned in the patterning step of the semiconductor layer, and a connection mask is provided. It is also characterized in that after removal, the ohmic layer is patterned using the source electrode and the drain electrode as a mask. Furthermore, in the method for manufacturing a TFT substrate for a display device, the method further includes the step of forming a common electrode on the substrate when forming the gate electrode, and the common electrode during the step of sequentially forming the gate insulating film, the semiconductor layer, and the metal layer. A gate insulating film, a semiconductor layer, and a metal layer are sequentially formed so as to cover the substrate, and a step of forming a pixel electrode located above the common electrode in a step of patterning the metal layer to form a source electrode and a drain electrode It is also characterized. Further, the present invention is also characterized in that the thickness of adjacent masks corresponding to the source electrode and the drain electrode has a thin film region that becomes thinner on the side farther than the thickness on the adjacent side. An example when the pattern forming method of the present invention is applied to a liquid crystal display device is as follows.
[0062]
According to the first method of manufacturing a liquid crystal display device of the present invention, a gate line and a gate electrode are formed on a first substrate, and then a gate insulating film covering the gate line and the gate electrode is formed on the first substrate. A step of forming a semiconductor film, an ohmic semiconductor film, and a source / drain metal film in order from the bottom on the gate insulating film; and a position above the gate electrode on the source / drain metal film. Forming a source electrode resist mask and a drain electrode resist mask, and etching and removing the source / drain metal film and the ohmic semiconductor film using the source electrode resist mask and the drain electrode resist mask as a mask. Forming a laminated pattern comprising the ohmic semiconductor film and the source / drain metal film; The source electrode resist mask and the drain electrode resist mask are reflowed in the lateral direction to connect the source electrode resist mask and the drain electrode resist mask to form a connection resist mask, and the connection resist mask is used for the stacking. A TFT substrate is formed by a manufacturing method including a step of covering at least a part of a pattern, and a step of forming a semiconductor island by etching and removing the semiconductor film using the connection resist mask as a mask. Subsequently, the first substrate is formed. A liquid crystal display device in which a second substrate facing the first substrate is disposed on the semiconductor island side to form a counter substrate, and a liquid crystal composition is filled between the TFT substrate and the counter substrate. A method of forming the connection resist mask comprises: The solution of an organic solvent to penetrate the resist mask and the drain electrode resist mask poles, characterized in that it is carried out by dissolving the reflow causing dissolution of the source electrode resist mask and the drain electrode resist mask.
[0063]
Next, according to the second method of manufacturing the liquid crystal display device of the present invention, the gate line and the gate electrode are formed on the first substrate, and then the gate line and the gate electrode are covered on the first substrate. A step of forming an insulating film; a step of depositing a semiconductor film, an ohmic semiconductor film, and a source / drain metal film in order from the bottom on the gate insulating film; and a step of forming the gate electrode on the source / drain metal film. Forming a resist mask for a source electrode and a resist mask for a drain electrode located above; and etching and removing the metal film for the source / drain using the resist mask for a source electrode and the resist mask for a drain electrode as a mask; A step of forming a metal film pattern for a source electrode and a metal film pattern for a drain electrode; The source electrode resist mask and the drain electrode resist mask are connected by reflowing the drain electrode resist mask in the lateral direction to form a connection resist mask, and the metal film pattern for the source electrode and the drain are connected by the connection resist mask. A step of covering at least a part of the electrode metal film pattern, a step of etching and removing the ohmic semiconductor film and the semiconductor film using the connection resist mask as a mask, and forming a semiconductor film stacked island; and the connection resist mask After peeling, the ohmic semiconductor film of the semiconductor film stacked island is etched away using the metal film pattern for source electrode and the metal film pattern for drain electrode as a mask, and the ohmic semiconductor film and the metal film for source / drain are From A TFT substrate is formed by a manufacturing method including a step of forming a stacked pattern and forming a semiconductor island made of the semiconductor film, and then facing the first substrate on the semiconductor island side of the first substrate. A method of manufacturing a liquid crystal display device in which a second substrate is disposed to form a counter substrate, and a liquid crystal composition is filled between the TFT substrate and the counter substrate, wherein the connection resist mask is formed Is performed by dissolution reflow in which an organic solvent solution is infiltrated into the source electrode resist mask and the drain electrode resist mask to cause dissolution of the source electrode resist mask and the drain electrode resist mask. And
[0064]
Next, in a third method of manufacturing a liquid crystal display device of the present invention, a gate line and a comb-like common electrode are formed on a first substrate, and then the gate line and the common electrode are formed on the first substrate. A step of forming a gate insulating film covering the electrode; a step of depositing a semiconductor film, an ohmic semiconductor film, and a source / drain metal film in order from the bottom on the gate insulating film; and the source / drain metal film Forming a resist mask for a source electrode and a resist mask for a drain electrode located above the gate line, and forming a resist mask for a pixel electrode so that an electrode is formed between comb-like electrodes of the common electrode And using the source electrode resist mask, the drain electrode resist mask, and the pixel electrode resist mask as a mask, A semiconductor electrode film is removed by etching to form a source electrode laminated pattern, a drain electrode laminated pattern, and a pixel electrode laminated pattern composed of the ohmic semiconductor film and the source / drain metal film, and at least the comb of the pixel electrode laminated pattern Forming the pixel electrode laminate pattern so that a tooth-like electrode is sandwiched between the comb-like electrodes of the common electrode, the source electrode resist mask, the drain electrode resist mask, and the pixel electrode resist mask And reconnecting at least the source electrode resist mask and the drain electrode resist mask to form a connection resist mask, and covering at least a part of the stacked pattern with the connection resist mask; and the connection resist The semiconductor using the mask as a mask A TFT substrate is formed by a manufacturing method including a step of forming a semiconductor island by etching away, and then, a second substrate facing the first substrate is disposed on the semiconductor island side of the first substrate. A method of manufacturing a liquid crystal display device in which a counter substrate is formed and a liquid crystal composition is filled between the TFT substrate and the counter substrate, wherein the step of forming the connection resist mask includes the step of forming a resist for the source electrode. An organic solvent solution is infiltrated into the mask and the resist mask for drain electrode, and is performed by dissolution reflow that causes dissolution of the resist mask for source electrode, the resist mask for drain electrode, and the resist mask for pixel electrode. And
[0065]
In the first, second, and third liquid crystal display device manufacturing methods according to the present invention, the step of forming the source electrode resist mask and the drain electrode resist mask is performed on the source / drain metal film. A thick resist mask is formed on the side where the resist mask for electrode and the resist mask for drain electrode face each other, and the resist mask for source electrode and the resist mask for drain electrode are formed on the side away from each other from the thick resist mask. Forming the connection resist mask is performed by dissolving and reflowing the thick resist mask and the thin resist mask, and the source electrode resist mask and the drain are formed. Channel region sandwiched between electrode resist masks The lateral spread of the connection resist mask is large in the vicinity, and the lateral spread of the connection resist mask gradually decreases as the distance from the channel region increases, thereby forming the source electrode resist mask and the drain electrode resist mask. Between the step of forming the connection resist mask and the step of forming the connection resist mask, just before the step of forming the connection resist mask, the source electrode resist mask and the drain electrode resist mask are etched to form only the thin resist mask. Removing the at least the thick resist mask to form a residual resist mask, and the step of forming the connected resist mask comprises dissolving and reflowing the residual resist mask to form a connected resist mask. Done. Further, these connection resist masks are formed in such a shape that the connection resist mask covers at least a channel region sandwiched between the source electrode resist mask and the drain electrode resist mask.
[0066]
In the first, second, and third liquid crystal display device manufacturing methods of the present invention, after the step of forming the semiconductor island, a protective insulating film that covers the stacked pattern and the semiconductor island is formed on the gate insulating film. And forming the protective insulating film and the gate insulating film on the gate line, and opening the protective insulating film on the stacked pattern to form a gate line contact hole and a source / drain contact, respectively. Forming a hole; and a gate line terminal electrode and a source / drain connection connected to the gate line and the stacked pattern through the gate line contact hole and the source / drain contact hole on the protective insulating film, respectively. The process of forming the upper electrode continues.
[0067]
In the first, second, and third liquid crystal display manufacturing methods of the present invention, the gate line, the gate metal film constituting the gate electrode, and the source / drain metal film are metal films having the following structures, respectively. One of them.
[0068]
・ ITO film
・ Indium tin alloy
・ Single layer structure of aluminum or aluminum alloy
・ Single layer structure of chromium or chromium alloy
-Two-layer structure where one layer is aluminum or aluminum alloy and the other layer is chromium or chromium alloy
-Two-layer structure where one layer is aluminum or aluminum alloy and the other layer is titanium or titanium alloy
-Two-layer structure where one layer is aluminum or aluminum alloy and the other layer is titanium nitride or titanium nitride alloy
-Two-layer structure where one layer is aluminum or aluminum alloy and the other layer is molybdenum or molybdenum alloy
-Two-layer structure where one layer is chromium or chromium alloy and the other layer is molybdenum or molybdenum alloy
・ The first and third layers are chromium or chromium alloy, and the second layer is aluminum or aluminum alloy.
・ The first and third layers are molybdenum or molybdenum alloy and the second layer is aluminum or aluminum alloy.
・ Three-layer structure of aluminum or aluminum alloy, molybdenum or molybdenum alloy, chromium or chromium alloy
・ Three-layer structure of aluminum or aluminum alloy, molybdenum or molybdenum alloy, titanium or titanium alloy
・ Three-layer structure of aluminum or aluminum alloy, titanium nitride or titanium nitride alloy, titanium or titanium alloy
[0069]
DETAILED DESCRIPTION OF THE INVENTION
A first embodiment of the present invention will be described with reference to FIG. Here, the first embodiment is an embodiment that forms the basic form of the embodiment described below, and FIG. 1 is a schematic cross-sectional view showing the wiring pattern forming method of the present embodiment in the order of steps. Furthermore, in the following embodiments of the present invention, the case where the organic film is a resist film will be described. However, the present invention is not limited to this and can be the organic film.
[0070]
According to the first embodiment of the present invention, as shown in FIG. 1A, an aluminum / copper alloy metal film 2 is formed on an insulating substrate 1 as described in the prior art. . Here, the film thickness of the metal film 2 is about 1 μm. Then, a resist mask 7 is formed in a predetermined region on the metal film 2 by a known photolithography technique. Here, the base of the metal film 2 is the insulating substrate 1. This insulating substrate is a transparent substrate such as glass used for a liquid crystal display device, amorphous silicon, silicon oxide film, silicon nitride film, silicon used for a semiconductor integrated circuit. An insulating film such as an oxide film or a silicon nitride film may be used.
[0071]
Next, as shown in FIG. 1B, the resist mask 7 is used as an etching mask, and the first etching is performed on the metal film 2 to form the first forward taper layer 15. Here, the etching is performed by plasma etching using chlorine, oxygen or the like as a reaction gas, and the cross section of the formed wiring has a forward taper shape.
[0072]
Next, after the first forward tapered layer 15 is formed, the resist mask 7 is exposed to the vapor of a chemical solution (that is, containing at least one of an organic solvent solution, an alkaline solution, or an acidic solution) together with the insulating substrate 1. Alternatively, it is immersed in a very dilute chemical solution (for example, 1/100 to 1/1000).
[0073]
In the following, an example in which a solution of an organic solvent is used as the chemical solution will be shown, but an alkaline solution or an acidic solution is also possible.
[0074]
In the case of exposure of the organic solvent solution to the vapor, there is an influence of the vapor density at the time of treatment, and the organic solvent temperature and the substrate temperature are treated at room temperature (around 20 ° C). When propylene glycol monoethyl ether is used, the steam exposure treatment is 0.1 to 3 minutes. However, when propylene glycol monoethyl ether having a low vapor density or N-methyl-2-pyrrolidone is used, It may take 20 minutes. Further, when the temperature of the organic solvent and the substrate temperature are increased, the treatment time is long, and when the temperature is low, the target dissolution reflow treatment is achieved by a short-time vapor exposure treatment.
[0075]
In the latter immersion treatment in an extremely dilute concentration organic solvent solution, if the concentration of the organic solvent is high, the resist dissolves in the organic solvent solution and causes peeling. It is necessary to adjust the concentration of the organic solvent in the solution so that a part of the solvent penetrates.
[0076]
Here, in this embodiment, acetone, propylene glycol monoethyl ether, tripropylene glycol monoethyl ether, and N-methyl-2-pyrrolidone were used as the organic solvent. The organic solvent is the organic solvent shown below. As long as at least one is included, it is applicable as a modification of this embodiment, and the same thing can be said also in embodiment described below. In the following, the organic solvent is divided into an organic solvent as a superordinate concept and a subordinate concept organic solvent that embodies it. (R represents an alkyl group or a substituted alkyl group, Ar represents a phenyl group or an aromatic ring other than a phenyl group) Organic solvent:
・ Alcohols (R-OH)
・ Alkoxy alcohols
Ethers (R—O—R, Ar—O—R, Ar—O—Ar)
・ Esters
・ Ketones
・ Glycols
・ Alkylene glycols
・ Glycol ethers
Specific examples of the organic solvent:
・ CH ₃ OH, C ₂ H ₅ OH, CH ₃ (CH ₂ XOH
・ Isopropyl alcohol (IPA)
・ Ethoxyethanol
・ Methoxy alcohol
・ Long chain alkyl ester
・ Monoethanolamine (MEA)
·acetone
・ Acetylacetone
・ Dioxane
·Ethyl acetate
・ Butyl acetate
·toluene
・ Methyl ethyl ketone (MEK)
・ Diethyl ketone
・ Dimethyl sulfoxide (DMSO)
・ Methyl isobutyl ketone (MIBK)
・ Butyl carbitol
・ N-Butyl acetate (nBA)
・ Gamma-butyrolactone
・ Ethyl cellosolve acetate (ECA)
・ Ethyl lactate
・ Ethyl pyruvate
・ 2-Heptanone (MAK)
・ 3-methoxybutyl acetate
·ethylene glycol
·Propylene glycol
・ Butylene glycol
・ Ethylene glycol monoethyl ether
・ Diethylene glycol monoethyl ether
・ Ethylene glycol monoethyl ether acetate
・ Ethylene glycol monomethyl ether
・ Ethylene glycol monomethyl ether acetate
・ Ethylene glycol mono-n-butyl ether
・ Polyethylene glycol
・ Polyprolene glycol
・ Polybutylene glycol
・ Polyethylene glycol monoethyl ether
・ Polydiethylene glycol monoethyl ether
・ Polyethylene glycol monoethyl ether acetate
・ Polyethylene glycol monomethyl ether
・ Polyethylene glycol monomethyl ether acetate
・ Polyethylene glycol mono-n-butyl ether
・ Methyl-3-methoxypropionate (MMP)
・ Propylene glycol monomethyl ether (PGME)
・ Propylene glycol monomethyl ether acetate (PGMEA)
・ Propylene glycol monopropyl ether (PGP)
・ Propylene glycol monoethyl ether (PGEE)
・ Ethyl-3-ethoxypropionate (FEP)
・ Dipropylene glycol monoethyl ether
・ Tripropylene glycol monoethyl ether
・ Polypropylene glycol monoethyl ether
・ Propylene glycol monomethyl ether propionate
・ Methyl 3-methoxypropionate
・ Ethyl 3-ethoxypropionate
・ N-methyl-2-pyrrolidone (NMP)
As a process for subsequent chemical solution reflow, a method in which it is mainly exposed to the vapor of an organic solvent solution will be described.
[0077]
As a specific example of this treatment method, as shown in FIG. 24, an organic solvent 520 such as N-methyl-2-pyrrolidone is put in a depth of 5 to 15 mm in a stainless bat container 510 having a depth of 20 mm, and the treatment surface is set. It is turned over and placed on the bat container 510, and a weight 540 is placed on the substrate 530 in order to seal the vapor atmosphere of the organic solvent 520 in the space between the stainless bat container 510 and the substrate 530. The temperature of the substrate 530 and the organic solvent 520 is kept at room temperature (around 20 ° C.). In this way, the treatment substrate 530 is exposed to the vapor of the organic solvent, and the vapor exposure treatment is performed. Here, when acetone or propylene glycol monoethyl ether having a high vapor density is used, the vapor exposure treatment is performed for 0.1 to 3 minutes, but tripropylene glycol monoethyl ether having a low vapor density or N-methyl-2-pyrrolidone is used. When using, a process of 5 to 20 minutes is performed.
[0078]
In the state where the above-described chemical solution, that is, the organic solvent solution is permeating into the resist, the resist is dissolved and reflow occurs (chemical solution reflow). Depending on the type, the organic solvent in the resist evaporated and the resist hardened. Moreover, since the chemical solution penetrated during dissolution, the resist was in an expanded state, but it was also found that the volume returned to the original state after the chemical solution evaporated. The resist is reflowed by this chemical reflow, and the resist spreads in the lateral direction as shown in FIG. Since this chemical solution reflow has a lower resist viscosity at the time of reflow compared to the above-described thermal reflow, the present invention completely covers the first forward taper layer 15 as shown in FIG. Reflow is performed so as to cover part of the surface of the metal film 2 as an etching film. On the other hand, thermal reflow tends to result in the structure shown in FIG. Also, this chemical reflow is about 10 μm at 20 ° C. for 3 minutes in a vapor of an organic solvent solution such as acetone or propylene glycol monoethyl ether having a high vapor density. Was able to reflow laterally. In this case, when the temperature of the organic solvent and the substrate temperature are high, the processing time is long, and when the temperature is low, the target dissolution reflow distance can be achieved in a short time.
[0079]
Here, after the chemical solution reflow, a heat treatment at 100 to 200 ° C. may be performed for 5 to 60 minutes after the chemical solution reflow treatment and before the etching treatment for the purpose of promoting the adhesion with the lower layer film.
[0080]
Next, the dissolved reflow resist mask 13 is used as an etching mask, and the remaining metal film 2 is subjected to the second etching to form the second forward taper layer 16. Also in this case, it is performed by plasma etching using chlorine, oxygen or the like as a reaction gas. The wiring 11 to be formed is partially stepped in cross section, but generally has a forward taper shape.
[0081]
In the first embodiment, the case where the metal film 2 is etched by the first etching and the second etching has been described. The present invention is not limited to such a method.
[0082]
Here, the material to be etched is not composed of one type of metal film, but is composed of two or more types of materials to be etched, and the upper layer of the material to be etched is etched with a resist mask, and dissolved reflow The underlying material to be etched may be etched with a resist mask. In this case, two types of patterns are formed by one photolithography process.
[0083]
In order to promote dissolution and reflow of the resist mask, after the first etching step, oxygen plasma treatment, that is, an O2 flow rate of 300 sccm, 100 Pa, RF, is used to remove the altered layer on the resist mask surface by the first etching. Processing is performed for 120 seconds in a plasma of power 1000 W. Alternatively, UV ozone treatment, that is, processing may be performed by heating the substrate at 100 to 200 ° C. and applying UV light in an ozone gas atmosphere. By this treatment, the altered resist surface layer is removed, and uniform dissolution reflow with little difference between the inside and the outside occurs.
[0084]
Among the conventional techniques, in the first conventional example (thermal reflow by heating), the volume shrinkage due to evaporation of the solvent due to heating becomes a negative factor in the spread of the planar dimensions during reflow, and the viscosity during reflow is heated. Since it is also related to the temperature, it is necessary to raise the heating temperature in order to reduce the viscosity and increase the spread, which is also a factor of volume shrinkage. For this reason, the first conventional example is disadvantageous in that it requires a certain amount of heating and is accompanied by volume shrinkage of the resist as compared with the method of the present invention that realizes forward taper by increasing the planar dimension of the resist. Met.
[0085]
On the other hand, in the first embodiment of the present invention, since it is a dissolution reflow by infiltrating a solvent or the like into the resist mask, it does not involve volume shrinkage, hardly requires heating, and has a large viscosity. Since the reduction can be reduced, the planar dimension of the resist mask can be increased by a simple method and with good adhesion before the second etching, so that a wiring with a forward taper structure can be easily formed. As a result, the problem of Conventional Example 1 was completely overcome.
[0086]
Next, a second embodiment of the present invention will be described with reference to FIGS. Here, FIG. 2 and FIG. 3 are schematic cross-sectional views of a part of the manufacturing process of the staggered TFT of the present invention.
[0087]
As shown in FIG. 2A, as in the third conventional example, a gate electrode 22 is formed on an insulating substrate 21 made of a transparent substrate such as glass, and a gate insulating film 23 having a thickness of 350 nm and a thickness of 200 nm are formed. The a-Si film 24, the n + type a-Si film 25 having a thickness of 50 nm, and the metal film 26 such as a Cr / Al alloy having a thickness of 250 nm are laminated and deposited.
[0088]
Next, resist masks 27 and 28 are formed on the metal film 26 by a known photolithography technique. These resist masks 27 and 28 are used as a first etching mask, and the metal film 26 and the n + -type a-Si film 25 are dry-etched.
[0089]
In this way, as shown in FIG. 2B, the ohmic contact layer 29 for the source electrode, the source electrode 31, the ohmic contact layer 30 for the drain electrode, and the drain electrode 32 are formed.
[0090]
Next, as described in the first embodiment, the resist masks 27 and 28 are exposed to the organic substrate vapor made of acetone together with the insulating substrate 21 for 1 to 3 minutes. In this manner, acetone gradually permeates the resist masks 27 and 28 to cause dissolution of the resist mask and reflow (hereinafter, referred to as chemical solution dissolution reflow, dissolution reflow, or chemical solution reflow). The resist masks 27 and 28 are expanded by the process of dissolving and reflowing the resist mask. As shown in FIG. 2C, the resist masks 27 and 28 are dissolved and reflowed so that the adjacent portions are united and integrated. The resulting dissolved reflow resist mask 33 is obtained.
[0091]
Since the dissolution reflow process has a low viscosity, the dissolution reflow resist mask 33 completely covers the ohmic contact layer 29, the source electrode 31, the ohmic contact layer 30, and the drain electrode 32 formed by the first etching, and further lower layers. Reflow is performed so as to cover part of the surface of the a-Si film 24. Incidentally, it has been confirmed that this dissolution reflow can be expanded to a maximum of 20 μm depending on the processing conditions.
[0092]
Here, in order to promote dissolution and reflow of the resist mask, after the first etching step, oxygen plasma treatment, that is, O plasma treatment is performed to remove the altered layer on the resist mask surface by the first etching. ₂ In some cases, treatment is performed for 120 seconds in plasma with a flow rate of 300 sccm, 100 Pa, and RF power of 1000 W, or UV ozone treatment, that is, treatment is performed by applying UV light in an ozone gas atmosphere by heating the substrate at 100 to 200 ° C. is there. By this treatment, the altered resist surface layer is removed, and uniform dissolution reflow with little difference between the inside and the outside occurs.
[0093]
The oxygen plasma treatment and UV ozone treatment also have the effect of improving the wettability of the film surface not covered with the resist, and the dissolved resist can easily reflow the film surface.
[0094]
Further, for the purpose of improving only the wettability with respect to the substrate (here, a-Si film, metal film) before the chemical solution reflow treatment, (1) the substrate is immersed in a hydrofluoric acid solution. (2) Plasma (O ₂ Fluorine gas (SF ₆ , CF ₄ , CHF ₃ Etc.) or fluorine gas and oxygen (SF) ₆ / O ₂ , CF ₄ / O ₂ , CHF ₃ / O ₂ Etc.))). (3) A method of improving the wettability by smoothing the surface of the film before chemical reflow or making it hydrophilic by performing etching of the upper layer film only by wet etching instead of dry etching.
[0095]
The pretreatment method and conditions selected before this chemical solution reflow treatment are selected according to need by measuring the removal rate of the resist surface altered layer and the wettability improvement rate of the film surface subjected to chemical solution reflow.
[0096]
Next, the dissolved reflow resist mask 33 is used as an etching mask, and the a-Si film 24 is subjected to second etching. In this way, the island layer 34 is formed as shown in FIG. Then, the dissolved reflow resist mask 33 is removed, and an inverted staggered TFT is formed in a predetermined region on the insulating substrate 21 as shown in FIG. Although description of subsequent steps is omitted, as an example, a pixel electrode, a passivation insulating film, an alignment film, and the like are formed to complete a TFT substrate, and then a second insulating substrate facing the insulating substrate 21 is prepared. In the case where a counter substrate is completed by forming a color filter, a black matrix, a transparent electrode, a passivation film, an alignment film, and the like thereon to manufacture a vertical electric field type liquid crystal display device, a TFT substrate and The liquid crystal display device is completed when the counter substrate is bonded and the liquid crystal composition is filled between the TFT substrate and the counter substrate after maintaining a predetermined interval with a spacer.
[0097]
In any of the embodiments described below, in the case of manufacturing a vertical electric field type liquid crystal display device, the above-described manufacturing process is continued after the illustrated manufacturing process.
[0098]
Of the conventional techniques, the third conventional example requires two photolithography steps, but in the second embodiment of the present invention, this is reduced to one time. In this way, the manufacturing process of the staggered TFT is greatly reduced, and the manufacturing cost is reduced. As a result, the problem of the third conventional example was completely overcome.
[0099]
In the second embodiment, the reflow for dimensional expansion due to dissolution of the resist mask is performed by exposing the resist masks 27 and 28 to vapor of an organic solvent made of acetone for 1 to 3 minutes. Acetone is gradually permeated to cause dissolution of the resist mask, but the present invention is not limited to this method. As another method, the method described above in the first embodiment of the present invention, which is dipped in an extremely dilute (for example, 1/100 to 1/1000) concentration organic solvent solution, is also possible. However, in the immersion treatment in an extremely dilute organic solvent solution, if the organic solvent concentration is high, the resist dissolves and peels in the organic solvent solution. It is necessary to adjust the concentration of the organic solvent in the solution to be extremely dilute so that a part of the water penetrates. As the organic solvent to be used, the organic solvents already listed in the first embodiment of the present invention, namely (alcohols (R—OH), alkoxy alcohols, ethers (R—O—R, Ar—O—R, Ar-O-Ar), esters, ketones, glycols, alkylene glycols, glycol ethers and specific examples of these organic solvents and mixed solvents thereof can be used.
[0100]
As a resist mask material suitable for acetone described in the first and second embodiments, the following organic resist is preferable. For example, as a material formed from a polymer compound, a photosensitizer, and other additives, there are a resist composed only of an organic material and a resist composed of a mixture of an organic material and an inorganic material. In a resist composed only of an organic material, there is polyvinyl cinnamate as an example of polyvinyl. Examples of rubber-based materials include those obtained by mixing a bisazide compound with cyclized polyisoprene or cyclized polybutadiene. An example of a novolac resin system is a mixture of a cresol novolac resin and naphthoquinonediazide-5-sulfonic acid ester. Examples of acrylic resin copolymer resins include polyacrylamide and polyamic acid. As another example, there is a resist to which bromine or iodine is added or contains a large amount. On the other hand, as a resist made of an organic material and an inorganic material, there is a siloxane as an example of a Si-containing resist or a resist containing polysiloxane, polysilane, polysilene, or carbosilane, and germanium is included as an example of a metal-containing resist other than Si. There is a resist. Further, the resist mask described in the first and second embodiments may be formed of either a negative type resist or a positive type resist. As the positive type, a novolac resin-based material, for example, a mixture of cresol novolac resin and naphthoquinonediazide-5-sulfonic acid ester is suitable. As the negative type, rubber-based materials such as cyclized polyisoprene or cyclized polybutadiene mixed with a bisazide compound are suitable.
[0101]
Further, in addition to the method described in the present invention, the resist mask is dissolved and reflowed. ₂ Etching after re-adjusting the resist mask spread size by reducing the area of the resist mask by removing the extra reflowed and spread portion of the resist mask when ashing or UV ozone treatment is performed In addition, it is added that the target etching pattern can be finely adjusted.
[0102]
Further, in addition to the method described in the present invention, after performing the etching process after the resist mask is dissolved and reflowed, unless the resist mask film thickness is impaired, the resist mask is again dissolved and reflowed. It should also be mentioned that if a method in which etching is performed and etching is performed again is used, patterning of a complicated shape is possible.
[0103]
Further, as described in the present invention, the pattern expansion by combining the resist mask with the dimensional expansion by dissolving and reflowing, the dimensional reduction by, for example, O2 ashing of the resist mask and the etching process several times or more is also possible. It should also be mentioned that this is possible and can be used to pattern complex shapes.
[0104]
Next, the basic embodiment of the present invention described above will be described more specifically in the third embodiment and thereafter. 4-7 is a figure which shows the manufacturing method of 3rd Embodiment in order of a manufacturing process, (a) is a schematic plan view which shows the mode of TFT vicinity in each figure, (b) is ( It is a schematic cross section along the cutting line AA ′ in a). In addition, in (a), the terminal portion from which the gate electrode is led out is also shown. This is because the terminal structure from which the gate electrode is led out is the terminal portion from which the drain electrode is led out. Because it is different. The terminal portion from which the drain electrode is derived is the same as the pixel electrode structure shown in FIG. The structure of the terminal portion is the same as in the third embodiment in the fourth and fifth embodiments.
[0105]
FIGS. 4B and 5B showing the manufacturing method of the third embodiment are the same as FIGS. 2A and 2B of the second embodiment of the present invention, respectively. Detailed description is omitted.
[0106]
As in the second embodiment, as shown in FIG. 4A, the gate electrode 42 (derived to the gate terminal electrode 142), the gate insulating film 43, and the a-layer that becomes the island layer are formed on the insulating substrate 41. Si film 44, ohmic contact layers 49 and 50 made of n + type a-Si film, source electrode 51 and drain electrode 52 are formed using resist masks 47 and 48 as masks.
[0107]
Next, as shown in FIG. 5B, a dissolved reflow resist mask 53 formed by dissolution and reflow is formed, and when the a-Si film 44 is etched using the mask, the island layer made of the a-Si film 44 is formed. 54 is formed. Thereafter, the dissolved reflow resist mask 53 is peeled and removed. As the stripping solution, a wet stripping process is performed using a stripping solution obtained by mixing DMSO (dimethyl sulfoxide) and monoethanolamine. After that, O ₂ Process in plasma or UV ozone.
[0108]
Next, as shown in FIG. 6B, after forming a passivation film 55, a photolithography process and SF ₆ / He gas = 50/150 sccm, 10 Pa, 1000 W, contact hole 56 is formed on source electrode 51 by dry etching treatment for 250 seconds. At this time, since the gate insulating film 43 and the passivation film 55 are covered on the gate terminal electrode 142, the contact hole 56 of the gate terminal electrode 142 is formed so as to penetrate them.
[0109]
Finally, as shown in FIG. 7B, after forming a transparent metal film made of ITO or the like, the pixel electrode 57 and the terminal portion electrode 58 are formed by a photolithography process and a ferric chloride etching solution. Thereby, a thin film transistor array for liquid crystal display and a pixel electrode are formed.
[0110]
In the present embodiment, as shown in the schematic plan view of FIG. 5A, the dissolved reflow resist mask 53 completely covers the source electrode 51 and the drain electrode 52 with a certain predetermined margin, and The TFT channel region 59 sandwiched between the source electrode 51 and the drain electrode 52 is reflowed laterally so as to completely cover, and the island layer 54 is patterned in accordance with the pattern of the dissolved reflow resist mask 53. I understand.
[0111]
Next, the manufacturing method of the 4th Embodiment of this invention is demonstrated with reference to FIGS. In each figure, (a) is a schematic plan view showing a state in the vicinity of the TFT, and (b) is a schematic cross-sectional view along a cutting line AA ′ in (a). This embodiment has the same basic structure and process as the third embodiment.
[0112]
The difference between this embodiment and the third embodiment will be described. As shown in FIG. 8B, the resist mask is made of a resist mask 67 having a normal film thickness (about 3 μm) and a thin film thickness (about 0.1 mm). 2 to 0.7 μm) of thin resist mask 68.
[0113]
As shown in FIG. 8A, the thick resist mask 67 is formed by increasing only the thickness of the resist mask on the source electrode 71 and the drain electrode 72 and located on the channel region 79 side. The thin resist mask 68 is formed by reducing the thickness of the resist mask at a portion away from the channel region 79.
[0114]
As a method for controlling the partial film thickness of the resist mask, (1) a light-shielding portion and a semi-light-shielding portion controlled to at least two or more transmitted light amounts are formed in a mask pattern of a reticle used in an exposure process. (2) Two or more types of reticle masks are used in the exposure process, and the exposure amount is changed at least in two or more steps. An example is a method in which the resist mask is formed by exposure.
[0115]
Based on the resist mask formed in this manner, first etching is performed to form ohmic contact layers 69 and 70, a source electrode 71, and a drain electrode 72.
[0116]
Next, as shown in FIG. 9B, when the thick resist mask 67 and the thin resist mask 68 are exposed to the vapor of an organic solvent together with the insulating substrate 61 for 1 to 3 minutes, the thick resist mask 67 and the thin resist mask 68 are exposed. Acetone gradually permeates 68, causing the resist mask to dissolve and reflow. By this resist reflow process, the areas of the thick resist mask 67 and the thin resist mask 68 are expanded as shown in FIG.
[0117]
In this case, however, the thick resist mask 67 of the dissolved reflow resist mask 73 has a large area and spreads in the horizontal direction around the channel region 79, and the thin resist mask 68 of the dissolved reflow resist mask 73. Is smaller in area than the thick resist mask 67.
[0118]
Next, when the second etching is performed on the a-Si film 64 using the dissolved reflow resist mask 73 as a mask, as shown in FIG. 9B, the island layer patterned broadly around the channel region 79 is formed. 74 is formed.
[0119]
In this case, by using the dissolved reflow resist mask 73, as shown in FIG. 10A, the size of the island layer 74 is large in the vicinity of the channel region 79, and the source electrode 71 and the drain separated from the channel region 79 are formed. The area around the electrode 72 is controlled to be small, and this is a point different from the third embodiment. This is because the resist layer 67, 68 for forming the source and drain electrodes is used to form a wide island layer in the vicinity of the TFT channel region so that the semiconductor active layer is formed with sufficient margin as the TFT. The island layer in the region away from the layer is intended to be formed with a width close to the width of the source electrode 71 and the drain electrode 72 in order to reduce the parasitic capacitance with the gate electrode (gate wiring) wired under the layer. is there. Thereby, compared to the third embodiment, there is an advantage that an extra island layer is not formed around the source wiring and the drain wiring.
[0120]
In the subsequent process, the dissolved reflow resist mask 73 is peeled off and removed, as in the third embodiment, as shown in FIGS. 10B and 11B, the passivation film 75, the contact hole 76, the pixel. By forming the electrode 77 and the terminal part electrode 78, a thin film transistor array for liquid crystal display and a pixel electrode are obtained.
[0121]
Next, the manufacturing method of the 5th Embodiment of this invention is demonstrated with reference to FIGS. In each figure, (a) is a schematic plan view showing a state in the vicinity of the TFT, and (b) is a schematic cross-sectional view along a cutting line AA ′ in (a). This embodiment has the same basic structure and process as the fourth embodiment.
[0122]
The difference between this embodiment and the fourth embodiment will be described. As shown in FIG. 12B, when forming a resist mask, the resist mask is a thick resist mask 87 having a normal film thickness (about 3 μm). And a thin resist mask 88 having a thin film thickness (about 0.2 to 0.7 μm).
[0123]
This is because a thick resist mask 87 is formed by thickening only the thickness of the resist mask located on the channel region 99 side above the source electrode 91 and the drain electrode 92, and the resist mask at a portion away from the channel region 99. A thin resist mask 88 is formed by reducing the thickness of the film. The first etching is performed based on the resist mask formed in this way, and ohmic contact layers 89 and 90, a source electrode 91, and a drain electrode 92 are formed.
[0124]
This embodiment is different from the fourth embodiment in that after this first etching, ashing is performed in an O 2 plasma atmosphere, and a thin resist mask 88 (thickness of about 0.2 to 0. 7 μm) is completely removed. As a result, as shown in FIG. 13B, only the thick resist mask 87 of the resist mask remains as the remaining resist mask 100.
[0125]
Next, when the remaining resist mask 100 in which only a part of the thick resist mask 87 remains is exposed to the vapor of the organic solvent for 1 to 3 minutes together with the insulating substrate 81, the organic solvent gradually permeates into the remaining resist mask 100, and the remaining resist mask 100 is exposed. The mask 100 is dissolved and reflowed (hereinafter referred to as dissolution reflow). By the process of dissolving and reflowing the remaining resist mask 100, as shown in FIG. 14B, the area of the remaining resist mask 100 is expanded to form a dissolved reflow resist mask 93.
[0126]
However, in this case, as shown in FIG. 13A, the remaining resist mask 100 is formed only on the channel region 99 side above the source electrode 91 and the drain electrode 92, and the two remaining resist masks 100 are dissolved by reflow. As shown in FIG. 14A, the combined reflow resist mask 93 is formed, and only the vicinity of the channel region 99 in the a-Si film 84 is covered. Here, the source electrode 91 and the drain electrode 92 located away from the channel region 99 are not covered with the dissolved reflow resist mask 93.
[0127]
Next, as shown in FIG. 14B, the island layer 94 is formed by performing second etching on the a-Si film 84 using the dissolved reflow resist mask 93 as a mask. In this case, as shown in FIG. 14A, by using the dissolved reflow resist mask 93, the island layer 94 is formed so as to be greatly expanded in the vicinity of the channel region 99, and in a region away from the channel region 99. The source electrode 91 and the drain electrode 92 serve as an etching mask instead of the resist, and the source electrode 91 and the drain electrode 92 (in addition to the two, are connected to the source electrode 91 and the drain electrode 92). The a-Si film 84 is etched in a self-aligned pattern (including the wiring), so that the island layer 94 is not excessively spread in a region away from the channel region 99 as compared with the fourth embodiment. Can be formed. This point is different from the fourth embodiment. In this embodiment, the island layers are formed in different shapes in the vicinity of the channel region of the TFT and in regions other than the vicinity of the channel by using the resist masks 88 and 87 for forming the source and drain electrodes. This is an object, and as described in the fourth embodiment, in particular, the parasitic capacitance between the island layer 94 and the gate wiring wired thereunder can be further reduced as compared with the fourth embodiment. There is.
[0128]
In the process following the formation of the island layer 94, the dissolved reflow resist mask 93 is peeled off and removed, as in the third embodiment, as shown in FIGS. 15A and 15B, a passivation film 95, a contact hole 96, a pixel. The electrode 97 and the terminal part electrode 98 are formed, and the thin-film transistor array for liquid crystal displays and a pixel electrode are obtained.
[0129]
Next, an example in which the present invention is applied to a horizontal electric field type liquid crystal display device is shown in FIGS. FIG. 16 shows the state of the TFT substrate for a display cell for one pixel. FIG. 16 (a) is a plan view when the TFT substrate is viewed from its upper surface, and FIG. A TFT substrate, a liquid crystal, and a CF substrate (referred to as a color filter substrate facing the TFT substrate, hereinafter referred to as a CF substrate) are cut along a plane orthogonal to the TFT substrate through the cutting line CC ′ in FIG. It is sectional drawing when doing. FIGS. 17 to 22 are manufacturing process cross-sectional views illustrating the manufacturing method of the TFT substrate of the horizontal electric field type liquid crystal display device in the order of processes, in which (a) is a section line CC in FIG. 16 (a). (B) and (c) are not shown in FIG. 16 (a), but are respectively a gate terminal as an external extraction terminal of the gate wiring and an external extraction terminal of the drain wiring. It is sectional drawing of a drain terminal.
[0130]
The operation of the horizontal electric field type liquid crystal display device will be briefly described with reference to FIG.
[0131]
On the insulating first transparent substrate 201 such as a glass substrate, first, a gate wiring 322 that also serves as the gate electrode 222 is wired in parallel on the substrate, and a common electrode 342 is also formed at the same time. The common electrode 342 is formed in a comb-like shape, and generates an electric field in a pair with a comb-like pixel electrode formed in a later step. A gate insulating film 223 is formed on the gate line 322 and the common electrode 342, and a drain wiring 332 is formed on the gate insulating film 223 so as to intersect the gate wiring 322. The drain wiring 332 also serves as the drain electrode 232, and simultaneously with the formation of the drain wiring 332, the source electrode 231 and a comb-like pixel electrode 257 that is an extension line thereof are formed. A passivation film 255 is formed so as to cover the drain wiring 332, the source electrode 231, and the pixel electrode 257. The gate wiring 322 and the drain wiring 332 have an insulating film opened on the substrate end portion for connection to the outside. Although not shown in FIG. 16, a contact hole is formed, and an electrical signal is applied to the gate wiring 322 and the drain wiring 332 from the outside through the contact hole.
[0132]
As shown in FIG. 16A, the pixel electrode 257 forms electrodes parallel to each other together with the common electrode 342 formed below, and a voltage is applied between them to thereby form the surface of the first transparent substrate 201. An electric field that is substantially parallel to the first transparent substrate 201 is generated, and the direction of the liquid crystal 318 to be filled between the first transparent substrate 201 and the opposite substrate is controlled.
[0133]
Next, a manufacturing method of the horizontal electric field type liquid crystal display device of the sixth embodiment will be described with reference to FIGS.
[0134]
First, the gate electrode 222 made of Cr or the like is formed on the first transparent substrate 201. At the same time, the common electrode 342 and the gate terminal electrode 242 are formed on other regions of the first transparent substrate 201 (FIG. 17). ... 1st PR process).
[0135]
Next, a silicon oxide film and a silicon nitride film (SiNx) are sequentially deposited on the entire surface of the first transparent substrate 201 to form a gate insulating film 223, followed by an a-Si film 224, an n + type a-Si film 225, and a source. A metal film 226 for drain is sequentially deposited, and resist masks 227, 228, and 229 are formed on the metal film 226. Using the resist masks 227, 228, and 229 as masks, the metal film 226 and the n + -type a-Si film 225 are patterned into the same pattern (FIG. 18... Second PR step). At this time, as shown in FIG. 16A, the resist mask 227 also serves as a mask for a comb-like pixel electrode at the center of the pixel, and the pixel electrode 257 and an ohmic contact layer (not shown). ) Is formed.
[0136]
Next, the resist masks 227, 228, and 229 are exposed to an organic solvent vapor made of acetone together with the first transparent substrate 201 for 1 to 3 minutes. In this way, acetone gradually permeates the resist masks 227, 228, and 229, causing the resist mask to dissolve and reflow. The resist mask 227, 228, and 229 are expanded by the process of dissolving and reflowing the resist mask. As shown in FIG. 19A, the resist masks 227 and 228 are melted and reflowed so that the adjacent portions are combined. An integrated dissolved reflow resist mask 233 is formed, and the resist mask 229 is increased in area by dissolution and reflow processing to become a dissolved reflow resist mask 253.
[0137]
Since the dissolution reflow process has a low viscosity, the dissolution reflow resist mask 233 completely covers the ohmic contact layer 249, the source electrode 231, the ohmic layer 250, and the drain electrode 232 formed by the first etching, and further, Reflow is performed so as to cover part of the surface of the a-Si film 224. In addition, at the drain terminal, the resist mask 229 spreads to form a dissolved reflow resist mask 253 by the dissolution reflow process, and completely covers the drain terminal electrode 252 and the ohmic contact layer formed by the first etching. It has been confirmed that this dissolution reflow can be expanded up to a maximum of 20 μm depending on processing conditions.
[0138]
Here, in order to promote dissolution and reflow of the resist mask, after the first etching step, oxygen plasma treatment for removing the altered layer on the resist mask surface by the first etching is performed according to the method described above. It is also possible. Furthermore, the treatment for improving only the wettability with respect to the substrate before the chemical solution reflow treatment can be performed according to the method already described.
[0139]
Next, the dissolved reflow resist masks 233 and 253 are used as etching masks, and second etching is performed on the a-Si film 224. In this way, island layers 234 and 254 are formed (FIG. 19).
[0140]
Next, the dissolved reflow resist masks 233 and 253 are removed, and after forming a passivation film 255, gate terminals and drains are formed by a photolithography step and dry etching treatment of SF6 / He gas = 50/150 sccm, 10 Pa, 1000 W, 250 seconds. Contact holes 256 and 276 are formed in the terminals, respectively. Here, in the gate terminal, the contact hole 256 penetrates the gate insulating film 223 and the passivation film 255, and in the drain terminal, the contact hole 276 penetrates only the passivation film 255 (FIG. 20... Third PR process). ).
[0141]
Next, the surface of the display portion excluding the terminal region is covered with an alignment film 317 (FIG. 21). Alternatively, as another form, after forming a transparent metal film made of ITO or the like so as to cover the contact holes 256 and 276, the gate terminal transparent electrode 267 and the drain terminal are transparent by a photolithography process and a ferric chloride etching solution. An electrode 268 is formed, the wiring lead-out resistance in the terminal portion is lowered, and the surface of the display portion excluding the terminal region is covered with an alignment film 317 (FIG. 22... 4th PR process).
[0142]
Here, the feature of the present invention is that two different mask patterns are formed in one PR and etching is performed twice using the respective masks. The pattern formed by the first etching and the second etching are performed. Since the difference in the formation pattern due to the above is too fine to be expressed in the plan view of FIG. 16A, an enlarged plan view and a sectional view of the circular area surrounded by the broken line of FIG. 16A are shown again in FIG. And FIG. 23B is a cross-sectional view taken along a cutting line DD ′ in FIG.
[0143]
As shown in FIG. 23A, in the first etching, the source electrode 232 and the drain electrode 231 and the ohmic layer thereunder are formed in the same shape, and in the second etching, the source electrode 231 and the drain electrode 231 are formed. The channel region 299 sandwiched between the 232 and the resist mask 227 and the resist mask 228 of FIG. 18A are connected by the resist dissolution reflow process of the present invention shown in FIG. Since it becomes the dissolved reflow resist mask 233, it is completely covered with the resist mask 233. In addition, the dissolved reflow resist mask 233 covers the source electrode 231, the drain electrode 232, and the a-Si film 224 with the widths of the source electrode 231 and the drain electrode 232 being uniformly increased except for the channel region 299. The channel region of the a-Si film (a part of the island layer 234) is formed by the second etching, and at the same time, the island layer having a shape in which the widths of the source electrode 231 and the drain electrode 232 are uniformly thickened outside the channel region. 234 is formed. Of course, the island layer below the pixel electrode 257 (and the ohmic layer below the pixel electrode 257) also has a shape in which the width of the pixel electrode 257 is uniformly increased.
[0144]
In the sixth embodiment, the method of using a resist mask having one film thickness in the manufacturing process from FIG. 18 to FIG. 19 has been described. However, the resist mask of the fourth embodiment shown in FIGS. It goes without saying that the island layer can also be formed by applying the forming method and the resist mask forming method of the fifth embodiment shown in FIGS. 12 to 14 to this embodiment.
[0145]
As described above, the active matrix substrate of the horizontal electric field type liquid crystal display device can be formed. However, the process in FIG. 19 described above requires the 1PR process in the conventional manufacturing method, but the manufacturing method of the present invention. It becomes unnecessary. Therefore, according to the manufacturing method of the present invention, it is possible to use the 4PR process where the conventional manufacturing method requires five PR processes. Furthermore, if the step of forming the terminal electrode of the transparent metal film in FIG. 22 is omitted, the active matrix substrate of the horizontal electric field type liquid crystal display device can be manufactured in three PR steps, and the manufacturing cost reduction effect is further increased. growing.
[0146]
Finally, a polarizing plate 210 is formed on the back surface of the first transparent substrate 201 (the surface of the first transparent substrate 201 on which no TFT is formed is referred to as the back surface), thereby completing the TFT substrate of the horizontal electric field type liquid crystal display device. (FIG. 16B).
[0147]
As shown in FIG. 16B, the color display of the liquid crystal display device is a color filter (hereinafter abbreviated as CF) substrate 300 that is made to enter the light 356 from the back surface of the first transparent substrate 201 and faces the TFT substrate 200. It is performed by irradiating.
[0148]
On the other hand, the CF substrate 300 is formed as follows.
[0149]
First, a second transparent substrate 301 made of a transparent insulating material such as glass, and a second insulating film 314 made of a black matrix 311, a color layer 313, a silicon nitride film (SiNx), etc. on one surface of the second transparent substrate 301, The conductive film 315 and the polarizing plate 316 on the other surface of the second transparent substrate 301 are provided, and the alignment film 343 is printed on the surface of the uppermost layer of the substrate by a method such as offset printing.
[0150]
The alignment films of the TFT substrate 200 and the CF substrate 300 thus obtained are rubbed, alignment film molecules are arranged in a predetermined direction, and a cell gap material is sandwiched so that the two substrates have a predetermined interval. In combination, the liquid crystal 318 is sealed in the gap.
[0151]
In addition, the mutual distance between the comb-like pixel electrode 257 and the common electrode 342 that effectively generates a lateral electric field with respect to the surface of the TFT substrate 200 is set to about 7 μm.
[0152]
The polarizing plate 210 and the polarizing plate 316 are set to a thickness of about 0.2 mm. The conductive film 315 is set to a thickness of about 50 nm. The first transparent substrate and the second transparent substrate are set to a thickness of approximately 0.7 mm. The black matrix 311 is set to a thickness of about 1 μm. The color layer 313 is set to a thickness of about 1 μm. The thickness of the second insulating film 314 is set to about 1 μm. The alignment film is set to a thickness of approximately 50 nm. The gate insulating film 223 is set to a thickness of about 500 nm. The passivation film 255 is set to a thickness of about 300 nm. The common electrode 342 is set to a thickness of about 400 nm. Further, the thickness (cell gap) of the liquid crystal 318 is set to 4.5 μm by arranging the spacers in the cell with an appropriate scattering density.
[0153]
The liquid crystal panel thus obtained has the transmission axis of the polarizing plate 210 of the TFT substrate 200 aligned with the liquid crystal alignment direction defined by the rubbing method, and the CF substrate 300 has an absorption axis that is the same as the TFT substrate 200 side. A full-color display is performed from black display to white display by attaching polarizing plates 316 orthogonal to each other, irradiating light 356 from the TFT substrate 200 side, and freely applying a potential difference between the pixel electrode 257 and the common electrode 342. Can do.
[0154]
Although the above is description of embodiment of this invention, this invention is not limited to said embodiment, In addition, various application forms or the modified example of said embodiment contains in it. .
[0155]
First, the formation of the ohmic contact layer of each embodiment by the etching of the n + type a-Si film of the second to sixth embodiments of the present invention is performed immediately after the etching of the metal film for the source / drain electrodes described in this embodiment. Without etching, only the metal film is first etched using the resist mask before dissolution reflow as a mask, and then the n + type a-Si film and a-Si film are etched using the dissolution reflow resist mask as a mask to form the island layer as a-Si. It is also possible to adopt a stacked film structure of a film and an n + type a-Si film. After that, after peeling off the dissolved reflow resist mask, an island layer made of an a-Si film is formed by etching only the n + type a-Si film of the laminated film using the drain electrode and the source electrode as a mask. Also good. In this case, as compared with the case described above, there are advantages that the pattern step at the time of dissolution reflow is small, and that the surface roughness due to etching is small, so that the dissolution reflow is easy.
[0156]
Further, in the second to sixth embodiments of the present invention, dissolution reflow by dissolving the resist mask exposes each resist mask to the vapor of the organic solvent for 1 to 3 minutes, and the organic solvent gradually permeates the resist mask. Although the mask is dissolved, the present invention is not limited to this method. As other methods, vapor exposure with a chemical solution (that is, a solution containing at least one of a solution of an organic solvent, an alkali solution, or an acid solution) already described in the first embodiment of the present invention, and extremely dilute A method of immersing in a chemical solution having a concentration (for example, 1/100 to 1/1000) (that is, a solution containing at least one of an organic solvent solution, an alkaline solution, or an acidic solution) is also possible. However, in the immersion treatment in an extremely dilute chemical solution (that is, a solution containing at least one of an organic solvent solution, an alkaline solution, or an acidic solution), the chemical solution (that is, an organic solvent solution, an alkaline solution, Or a solution containing at least one of acidic solutions) If the concentration is high, the resist dissolves in the chemical solution (that is, a solution containing at least one of an organic solvent solution, an alkaline solution, or an acidic solution) and causes peeling. It is necessary to adjust the concentration of the chemical solution in the solution to be extremely dilute so that a part of the chemical solution penetrates into the resist without causing dissolution and peeling. Among the chemical solutions, as the organic solvent used as the organic solvent solution, the organic solvents already listed in the first embodiment of the present invention, that is, (alcohols (R—OH), alkoxy alcohols, ethers (R—O) are used. -R, Ar-O-R, Ar-O-Ar), esters, ketones, glycols, alkylene glycols, glycol ethers, and listed organic solvents and mixed solvents thereof can be used. It is.
[0157]
Note that the resist mask described in the third to sixth embodiments may be formed of either a negative resist or a positive resist.
[0158]
Furthermore, in addition to the method described in the present invention, after the resist mask is dissolved and reflowed, for example, when O2 ashing treatment of the resist mask or UV ozone treatment is performed, the portion of the resist mask that is excessively reflowed and spreads out. By reducing the area of the resist mask by the removal, it is possible to finely adjust the target etching pattern by performing the etching after readjusting the spread size of the resist mask.
[0159]
In addition to the method described in the present invention, the etching process is performed for dissolving and reflowing the resist mask, and then the resist mask is dissolved and reflowed again to perform etching again. Note that patterning is also possible.
[0160]
In order to further promote dissolution and reflow of the resist mask in the third to sixth embodiments described above, in order to remove the altered layer on the resist mask surface due to the first etching after the first etching step, Oxygen plasma treatment, that is, treatment is performed for 100 seconds in plasma with an O2 flow rate of 300 sccm, 10 to 200 Pa, and RF power of 1000 W. Alternatively, UV ozone treatment is performed, that is, the substrate is heated at 100 to 200 ° C. and subjected to UV light in an ozone gas atmosphere. By this treatment, the altered resist surface layer is removed, and uniform dissolution reflow with little difference between the inside and the outside occurs.
[0161]
The oxygen plasma treatment and UV ozone treatment also have the effect of improving the wettability of the film surface not covered with the resist, and the dissolved resist can easily reflow the film surface. The treatment method and conditions at this time are selected according to necessity by measuring the removal rate of the resist surface altered layer and the improvement rate of the wettability of the film surface to which the chemical solution is reflowed.
[0162]
In the fourth conventional example (method using volume expansion by silylation), there is no problem even if the resist is expanded in the lateral direction up to 0.1 to 2.0 μm using volume expansion. In the formation of the channel portion of about 5 μm to be expanded, there is a problem of adhesion, but in the third, fourth and fifth embodiments of the present invention, the adhesion force is good even at 20 μm, and the channel of about 5 μm. There was no problem as long as the portion was formed, and the problem of the third conventional example could be completely overcome.
[0163]
In addition, the metal film, gate electrode, source electrode, drain electrode, common electrode, and pixel electrode shown in the first to sixth embodiments of the present invention are, for example, an ITO film, other transparent conductive films, indium tin. Alloy, single layer structure of aluminum (or aluminum alloy), single layer structure of chromium (or alloy of chromium), or aluminum (or alloy of aluminum) and chromium (or alloy of chromium) Or a two-layer structure of aluminum (or an alloy of aluminum) and titanium (or an alloy of titanium), or an aluminum (or alloy of aluminum) and titanium nitride (or an alloy of titanium nitride) ), Or aluminum (or aluminum alloy) and molybdenum (or molybdenum alloy) Or a two-layer structure of chromium (or an alloy of chromium) and molybdenum (or an alloy of molybdenum), or chromium (or an alloy of chromium) and aluminum (or an alloy of aluminum) Three-layer structure with chromium (or alloy of chromium), or three-layer structure of molybdenum (or alloy of molybdenum), aluminum (or alloy of aluminum) and molybdenum (or alloy of molybdenum), or Three-layer structure of aluminum (or aluminum alloy), molybdenum (or molybdenum alloy) and chromium (or chromium alloy), or aluminum (or aluminum alloy) and molybdenum (or molybdenum alloy) ) And titanium (or an alloy of titanium), or aluminum (Or an alloy of aluminum), titanium nitride (or an alloy of titanium nitride) and titanium (or an alloy of titanium), It is confirmed that the pattern can be formed without any problem, and is a suitable material in this pattern forming method. Examples of the thickness of the metal layer are 150 nm for Cr single layer, 100/150 nm for Cr / Al, 50/50/150 nm for Ti / TiN / Al, 50/150/50 nm for Ti / Al / Ti. In the case of TiN / Al / TiN, it is 50/150/50 nm.
[0164]
The third, fourth, and fifth embodiments of the present invention are methods for forming up to an inverted staggered TFT pattern. However, the pattern forming method of the present invention is not limited to this, and the TFT pattern forming method is not limited thereto. Also, a method of forming a TFT pattern with a color filter in which a color (color filter) layer or a planarizing film and a color (color filter) layer are formed below the pixel electrode can be implemented.
[0165]
Finally, the pattern forming methods shown in the first to sixth embodiments of the present invention described above include, for example, a flat display panel liquid crystal display (LCD), electroluminescence display (EL), field emission display (FED), fluorescence It is used as a manufacturing method in a manufacturing process of a display device, an active element substrate of a plasma display panel (PDP), or a substrate provided with an integrated circuit.
[0166]
In the above description, the glass substrate is taken as an example of the substrate. However, the substrate to which the present invention can be applied is not limited to this, and is also applicable to an insulating substrate such as a nitride film substrate and an aluminum nitride substrate, and a semiconductor substrate such as a silicon substrate. Applicable.
[0167]
【The invention's effect】
As described above, in the pattern forming method of the present invention, the resist mask once used for the etching mask is dissolved and reflowed in the manufacturing process of the semiconductor device, and the dimension is expanded while maintaining the volume before the dissolution and reflowing. Change to an etching mask. By doing so, the forward taper of the pattern such as the wiring becomes easy. In addition, since two or more types of patterns can be formed on the material to be etched through one photolithography process, the manufacturing process can be shortened.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing a first embodiment of the present invention in the order of manufacturing steps.
FIG. 2 is a schematic cross-sectional view showing a second embodiment of the present invention in the order of manufacturing steps.
3 is a schematic cross-sectional view showing a manufacturing step that follows FIG. 2; FIG.
4A and 4B are a schematic plan view and a schematic cross-sectional view showing a manufacturing process according to a third embodiment of the present invention.
FIG. 5 is a schematic plan view and a schematic cross-sectional view showing a manufacturing process subsequent to FIG. 4;
6 is a schematic plan view and a schematic cross-sectional view showing a manufacturing process subsequent to FIG. 5. FIG.
7 is a schematic plan view and a schematic cross-sectional view showing a manufacturing process subsequent to FIG. 6. FIG.
FIGS. 8A and 8B are a schematic plan view and a schematic cross-sectional view showing a manufacturing process of the fourth embodiment of the present invention. FIGS.
9 is a schematic plan view and a schematic cross-sectional view showing a manufacturing process subsequent to FIG. 8. FIG.
10 is a schematic plan view and a schematic cross-sectional view showing a manufacturing process subsequent to FIG. 9. FIG.
11 is a schematic plan view and a schematic cross-sectional view showing a manufacturing process subsequent to FIG. 10; FIG.
12A and 12B are a schematic plan view and a schematic cross-sectional view showing a manufacturing process according to the fifth embodiment of the present invention.
13 is a schematic plan view and a schematic cross-sectional view showing a manufacturing process subsequent to FIG. 12. FIG.
14 is a schematic plan view and a schematic cross-sectional view showing a manufacturing process subsequent to FIG. 13. FIG.
15 is a schematic plan view and a schematic cross-sectional view showing a manufacturing process subsequent to FIG. 14. FIG.
FIG. 16 is a schematic plan view and a schematic cross-sectional view showing a liquid crystal display device according to a sixth embodiment of the present invention.
FIG. 17 is a schematic cross-sectional view showing the manufacturing process of the sixth embodiment of the present invention.
18 is a schematic cross-sectional view showing a manufacturing step that follows FIG. 17; FIG.
FIG. 19 is a schematic cross-sectional view showing a manufacturing step that follows FIG. 18;
20 is a schematic cross-sectional view showing a manufacturing step that follows FIG. 19; FIG.
FIG. 21 is a schematic cross-sectional view showing a manufacturing step that follows FIG. 20;
22 is a schematic cross-sectional view showing a manufacturing step different from FIG. 21 following FIG. 20; FIG.
FIG. 23 is an enlarged schematic plan view and an enlarged schematic sectional view showing a liquid crystal display device according to a sixth embodiment of the present invention.
FIG. 24 is a schematic cross-sectional view of a dissolution reflow apparatus used in an embodiment of the present invention.
FIG. 25 is a schematic cross-sectional view showing the manufacturing process of the first conventional example.
FIG. 26 is a schematic cross-sectional view showing the manufacturing process of the second conventional example.
FIG. 27 is a schematic cross-sectional view showing the manufacturing process of the third conventional example.
FIG. 28 is a schematic cross-sectional view showing a manufacturing process of the fourth conventional example.
FIG. 29 is a schematic cross-sectional view showing a manufacturing process of the fifth conventional example.
[Explanation of symbols]
1, 2, 41, 61, 81, 401, 421, 441 Insulating substrate
2, 26, 102, 122, 146, 226, 402, 422, 446 Metal film
7, 27, 28, 47, 48, 107, 227, 228, 229, 407, 427, 467, 468, 487, 488 Resist mask
11, 411, 431 wiring
13, 33, 53, 73, 93, 233, 253 Dissolved reflow resist mask
15, 415, 435 First forward tapered layer
16, 416, 436 Second forward taper layer
22, 42, 62, 82, 222, 442 Gate electrode
23, 43, 63, 83, 223, 443 Gate insulating film
24, 44, 64, 84, 224, 444, 464, 484 a-Si film
25, 225, 445 n + type a-Si film
29, 30, 49, 50, 69, 70, 89, 90, 249, 250, 449, 450 Ohmic contact layer
31, 51, 71, 91, 151, 231, 451 Source electrode
32, 52, 72, 92, 152, 232, 452 Drain electrode
34, 54, 74, 94, 234, 254, 454, 474, 495, 496 island layers
55, 75, 95, 255 Passivation film
56, 76, 96, 256, 276 Contact hole
57, 77, 97, 257 Pixel electrode
58, 78, 98 Terminal electrode
79, 99, 299 channel region
67, 87 thick resist mask
68, 88 Thin resist mask
100 Residual resist mask
447, 448 First resist mask
142, 162, 182, 242 Gate terminal electrode
200 TFT substrate
201 1st transparent substrate
210, 316 Polarizing plate
252 Drain terminal electrode
267 Gate terminal transparent electrode
268 Drain terminal transparent electrode
300 CF substrate
311 Black Matrix
313 color layer
314 Second insulating film
315 conductive film
317 Alignment film
318 liquid crystal
322 Gate wiring
332 Drain wiring
342 Common electrode
356 light
413, 493, 494 Thermal reflow resist mask
432 Side etching part
433, 473 Silylated resist mask
453 Second resist mask
510 stainless bat container
520 Organic solvent
530 treated substrate
540 weight

Claims (101)

Forming an organic film having a predetermined pattern on the film to be etched; removing part of the film to be etched from the surface using the organic film as a mask; exposing the film to be etched and the organic film; a step of the coated coated region, and forming a modified organic film and having a to extend different from said predetermined pattern pattern up to the exposed area by deforming the organic film, the deformation organic layer Examples mask a pattern forming method comprising the step of etching the etching target film, the step of forming the modified organic film, by exposing either infiltrating an organic solvent in the organic layer, the dissolution of the organic layer performed by dissolving the reflow causing Rupa turn-forming method. In the step of forming the organic film, an adjacent organic film adjacent to the organic film is formed, and in the step of forming the deformed organic film, the adjacent organic film becomes an adjacent deformed organic film, and the deformed organic film and The pattern forming method according to claim 1, wherein the patterns are combined. The pattern forming method according to claim 1, further comprising a step of removing a part of the deformed organic film between the step of forming the deformed organic film and the step of etching the exposed region of the film to be etched. The step of removing a part of the deformed organic film is performed by performing an ashing process using oxygen or an ozone process using ultraviolet rays on the deformed organic film to reduce the area of the deformed organic film. The pattern formation method of Claim 3. The process from the step of forming the deformed organic film to the step of etching the exposed region of the film to be etched is repeated at least once after the step of etching the exposed region of the film to be etched. A pattern forming method according to any one of the above. 6. The pattern forming method according to claim 1, wherein at least the last etching among the etching of the film to be etched is performed by wet etching. The pattern formation method according to claim 1, wherein the organic solvent solution includes at least one of the following organic solvents. Organic solvent (R represents an alkyl group or a substituted alkyl group, Ar represents a phenyl group or an aromatic ring other than a phenyl group):
・ Alcohols (R-OH)
・ Alkoxy alcohols ・ Ethers (R—O—R, Ar—O—R, Ar—O—Ar)
・ Esters, ketones, glycols, alkylene glycols, glycol ethers The pattern forming method according to claim 1, wherein the dissolution reflow is performed by exposure to vapor of a solution of the organic solvent. The pattern formation method according to claim 1, wherein the dissolution reflow is performed by immersing in a solution of the organic solvent. The pattern forming method according to claim 1, wherein the organic film includes a plurality of organic films having different film thicknesses. The pattern forming method according to claim 10, wherein when the organic film is a photosensitive organic film, the plurality of organic films having different film thicknesses are obtained by changing an exposure amount with respect to the photosensitive organic film. The organic film is composed of a plurality of organic films having different thicknesses, and the etched film is partially removed from the surface using the organic film as a mask, and the etched film is covered with the exposed region and the organic film. A plurality of different thicknesses constituting the organic film by etching the organic film between the step of forming the covering region and the step of deforming the organic film to form the deformed organic film extending to the exposed region 12. The pattern formation according to claim 10 or 11, wherein a step of removing a relatively thin organic film from the organic film to leave a thicker organic film than the relatively thin organic film is performed. Method. Removing part of the film to be etched from the surface using the organic film as a mask to form the film to be etched to be an exposed region and a coating region covered with the organic film; between the step of forming a modified organic layer extending to the exposed region, a pattern forming method according to any one of claims 1 to 12 by a step of removing the alteration layer of the surface of the organic film. The pattern forming method according to claim 13, wherein the step of removing the altered layer on the surface of the organic film is performed by performing plasma treatment or UV ozone treatment on the organic film. The plasma processing gas is any one of a plasma processing gas including an O ₂ gas, a plasma processing gas including a fluorine-based gas, and a plasma processing gas including a mixed gas of an O ₂ gas and a fluorine-based gas. The pattern formation method of Claim 14 performed by using. When the plasma processing gas is a plasma processing gas containing a fluorine-based gas, it is a gas containing any of SF ₆ , CF ₄ , and CHF ₃ , and the plasma processing gas is an O ₂ gas and a fluorine-based gas. The pattern forming method according to claim 14, comprising a gas for plasma processing including a mixed gas of any one of SF ₆ / O ₂ , CF ₄ / O ₂ , and CHF ₃ / O ₂ . Removing part of the film to be etched from the surface using the organic film as a mask to form the film to be etched to be an exposed region and a coating region covered with the organic film; The pattern forming method according to claim 1, wherein a step of immersing the film to be etched and the organic film in a hydrofluoric acid solution is performed during the step of forming the deformed organic film extending to the exposed region. The film to be etched includes a first film and a second film in order from the bottom, and the second film is removed by etching using the organic film as a mask, and the first film is used as a mask for the deformed organic film. The pattern forming method according to claim 1, wherein the pattern is removed by etching. 19. The pattern forming method according to claim 18, wherein the first film is a first metal film, and the second film is a second metal film made of a material different from that of the first metal film. 19. The pattern forming method according to claim 18, wherein the first film is a silicon film, and the second film is a silicon film for ohmic contact and a metal film containing impurities at a high concentration in order from the bottom. 19. The pattern forming method according to claim 18, wherein the first film is a silicon film and an ohmic contact silicon film containing impurities at a high concentration in order from the bottom, and the second film is a metal film. The silicon film constitutes a semiconductor layer of a thin film transistor, the ohmic contact silicon film and the metal film constitute a source electrode and a drain electrode of the thin film transistor, and the organic film is composed of an organic film having a plurality of thicknesses. The organic film comprises a thick organic film formed thick on a channel side of the semiconductor layer and a thin organic film formed thin on a side away from the channel of the semiconductor layer. Pattern forming method. After forming the source electrode and the drain electrode of the thin film transistor, the organic film is etched from the surface to leave only the thick film organic film on the source electrode and the drain electrode, and deform the thick film organic film. The pattern forming method according to claim 22, wherein the pattern is a deformed organic film. The pattern forming method according to claim 1, wherein the organic film is a resist film. The pattern forming method according to any one of claims 1 to 23, wherein a cross-sectional shape of the film to be etched after etching with the deformed organic film is tapered or stepped. Law. Forming a gate line and a gate electrode on the first substrate, and subsequently forming a gate insulating film covering the gate line and the gate electrode on the first substrate; and sequentially forming the gate insulating film on the gate insulating film from the bottom. Depositing a semiconductor film, an ohmic semiconductor film, a source / drain metal film, and forming a source electrode resist mask and a drain electrode resist mask located above the gate electrode on the source / drain metal film; Etching the source / drain metal film and the ohmic semiconductor film using the source electrode resist mask and the drain electrode resist mask as a mask, and removing the ohmic semiconductor film and the source / drain metal. A step of forming a laminated pattern comprising a film, the resist mask for source electrode, and the A step of reflowing a resist mask for a rain electrode in a lateral direction to connect the resist mask for a source electrode and the resist mask for a drain electrode to form a connected resist mask, and covering at least part of the stacked pattern with the connected resist mask And a step of forming a semiconductor island by etching and removing the semiconductor film using the connection resist mask as a mask, and subsequently forming the TFT substrate on the semiconductor island side of the first substrate. A method of manufacturing a liquid crystal display device, comprising: disposing a second substrate opposite to one substrate to form a counter substrate; and further filling a liquid crystal composition between the TFT substrate and the counter substrate. The step of forming a mask includes the source electrode resist mask and the drain electrode. Resist mask solution of organic solvent is infiltrated into, carried out by dissolving the reflow cause dissolution of the resist mask and the drain electrode resist mask the source electrode, forming a resist mask and the drain electrode resist mask the source electrode Forming a thick resist mask on the source / drain metal film on at least a part of the side where the source electrode resist mask and the drain electrode resist mask face each other; A method of manufacturing a liquid crystal display device, comprising: forming a thin resist mask thinner than the thick resist mask in at least a part of a region where the resist mask for drain and the resist mask for drain electrode are away from each other . Forming a gate line and a gate electrode on the first substrate, and subsequently forming a gate insulating film covering the gate line and the gate electrode on the first substrate; and sequentially forming the gate insulating film on the gate insulating film from the bottom. Depositing a semiconductor film, an ohmic semiconductor film, a source / drain metal film, and forming a source electrode resist mask and a drain electrode resist mask located above the gate electrode on the source / drain metal film; And a step of etching and removing the source / drain metal film using the source electrode resist mask and the drain electrode resist mask as a mask to form a source electrode metal film pattern and a drain electrode metal film pattern. And reflow the resist mask for source electrode and the resist mask for drain electrode in the lateral direction. The source electrode resist mask and the drain electrode resist mask are connected to form a connection resist mask, and at least a part of the metal film pattern for the source electrode and the metal film pattern for the drain electrode is connected with the connection resist mask. A step of covering, a step of etching and removing the ohmic semiconductor film and the semiconductor film using the connection resist mask as a mask to form a semiconductor film stacked island, and after peeling the connection resist mask, The ohmic semiconductor film is etched away using the metal film pattern for source electrode and the metal film pattern for drain electrode as a mask to form a laminated pattern composed of the ohmic semiconductor film and the source / drain metal film, and the semiconductor Is it a membrane A TFT substrate is formed by a manufacturing method including a step of forming a semiconductor island, and then a second substrate facing the first substrate is disposed on the semiconductor island side of the first substrate to form a counter substrate Further, in the method of manufacturing a liquid crystal display device, the liquid crystal composition is filled between the TFT substrate and the counter substrate, and the step of forming the connection resist mask includes the source electrode resist mask and the drain the electrode resist mask infiltrated solution of an organic solvent is carried out by dissolving the reflow cause dissolution of the resist mask and the drain electrode resist mask the source electrode, the source electrode resist mask and the drain electrode resist A step of forming a mask includes the step of forming the source electrode resist resist on the source / drain metal film. A thick resist mask is formed on at least a part of the side where the mask and the drain electrode resist mask face each other, and at least a part of the side where the source electrode resist mask and the drain electrode resist mask are separated from each other A method of manufacturing a liquid crystal display device, which is performed by forming a thin resist mask thinner than the thick resist mask in a region . Forming a gate line and a comb-like common electrode on the first substrate, and subsequently forming a gate insulating film covering the gate line and the common electrode on the first substrate; A step of depositing a semiconductor film, an ohmic semiconductor film, and a source / drain metal film in order from the bottom, and a source electrode resist mask and a drain electrode located above the gate line on the source / drain metal film Forming a resist mask and forming a pixel electrode resist mask so that an electrode is formed between the comb-like electrodes of the common electrode; the source electrode resist mask; the drain electrode resist mask; Using the pixel electrode resist mask as a mask, the source / drain metal film and the ohmic semiconductor film are removed by etching, and the ohmic semiconductor film is removed. Forming a source electrode laminated pattern, a drain electrode laminated pattern, and a pixel electrode laminated pattern, each of which includes at least a comb-like electrode of the pixel electrode laminated pattern. Forming the pixel electrode laminated pattern to be sandwiched between comb-shaped electrodes, and reflowing at least the source electrode resist mask, the drain electrode resist mask, and the pixel electrode resist mask in the lateral direction. A step of connecting a resist mask for a source electrode and a resist mask for a drain electrode to form a connection resist mask, covering the at least part of the stacked pattern with the connection resist mask, and etching the semiconductor film using the connection resist mask as a mask Remove to form semiconductor island A TFT substrate is formed by a manufacturing method including a step, a second substrate facing the first substrate is disposed on the semiconductor island side of the first substrate, and a counter substrate is formed. A method of manufacturing a liquid crystal display device in which a liquid crystal composition is filled between a substrate and the counter substrate, wherein the step of forming the connection resist mask is organic to the source electrode resist mask and the drain electrode resist mask. the solution of the solvent infiltrated, the source electrode resist mask is carried out by dissolving the reflow causing dissolution of the drain electrode resist mask and the pixel electrode resist mask, the source electrode resist mask and the drain electrode resist A step of forming a mask includes the step of forming the source electrode resist resist on the source / drain metal film. A thick resist mask is formed on at least a part of the side where the mask and the drain electrode resist mask face each other, and at least a part of the side where the source electrode resist mask and the drain electrode resist mask are separated from each other A method of manufacturing a liquid crystal display device, which is performed by forming a thin resist mask thinner than the thick resist mask in a region . Between the step of forming the resist mask for source electrode and the resist mask for drain electrode and the step of forming the connection resist mask, immediately before the step of forming the connection resist mask, the resist mask for source electrode and 29. The liquid crystal display device according to claim 26, further comprising a step of etching the drain electrode resist mask to remove only the thin resist mask to leave at least the thick resist mask to form a residual resist mask. Manufacturing method. 30. The method of manufacturing a liquid crystal display device according to claim 29, wherein the step of forming the connection resist mask is performed by dissolving and reflowing the remaining resist mask to form a connection resist mask. In the step of forming the connection resist mask, the connection resist mask covers at least a channel region sandwiched between the source electrode resist mask and the drain electrode resist mask and is further away from the channel region. the method according to any one of claims 26 to 30 lateral extent of the mask is gradually reduced so formed. 32. The method of manufacturing a liquid crystal display device according to claim 29, wherein the connection resist mask is formed in a shape covering at least a channel region sandwiched between the source electrode resist mask and the drain electrode resist mask. After the step of forming the semiconductor island, a step of forming a protective insulating film covering the stacked pattern and the semiconductor island on the gate insulating film, and the protective insulating film and the gate insulating film on the gate line. Opening the protective insulating film on the stacked pattern to form a gate line contact hole and a source / drain contact hole, respectively, and forming the gate line contact hole and the gate line contact hole on the protective insulating film. 33. The liquid crystal display according to claim 26, further comprising a step of forming a gate line terminal electrode and a source / drain upper electrode connected to the gate line and the stacked pattern through a source / drain contact hole, respectively. Device manufacturing method. 34. The liquid crystal display device according to claim 26, wherein the gate line, the gate metal film constituting the gate electrode, and the source / drain metal film are each a metal film having the following structure. Method.
・ ITO film ・ Indium tin alloy ・ Single layer structure of aluminum or aluminum alloy ・ Single layer structure of chromium or chromium alloy ・ One layer is aluminum or aluminum alloy and the other layer is double layer structure of chromium or chromium alloy ・ One layer Is a two-layer structure of aluminum or an aluminum alloy and the other layer is titanium or a titanium alloy. One layer is aluminum or an aluminum alloy and the other layer is a two-layer structure of titanium nitride or a titanium nitride alloy. One layer is aluminum or aluminum. Alloy, the other layer is molybdenum or molybdenum alloy two-layer structure. One layer is chromium or chromium alloy, the other layer is molybdenum or molybdenum alloy two-layer structure. The first and third layers are chromium or chromium alloy. The second layer is a three-layer structure of aluminum or aluminum alloy. The first and third layers Is a molybdenum or molybdenum alloy and the second layer is a three-layer structure of aluminum or aluminum alloy. Aluminum or aluminum alloy, molybdenum or molybdenum alloy, chromium or chromium alloy three-layer structure. Aluminum or aluminum alloy, molybdenum or molybdenum alloy, titanium Or three-layer structure of titanium alloy ・ Three-layer structure of aluminum or aluminum alloy, titanium nitride or titanium nitride alloy, titanium or titanium alloy In a method for manufacturing a TFT substrate, a step of forming a gate electrode on the substrate, a step of sequentially forming a gate insulating film, a semiconductor layer, and a metal layer so as to cover the gate electrode, and patterning the metal layer to form a source electrode Forming a mask composed of a plurality of organic films having different thicknesses on the metal layer, forming a deformed mask by deforming the mask, and forming the deformed mask using the deformed mask. And a step of patterning the semiconductor layer. In the method for manufacturing a TFT substrate, a step of forming a gate electrode on the substrate, a step of sequentially forming a gate insulating film, a semiconductor layer, and a metal layer so as to cover the gate electrode, and a step on the metal film for source / drain Forming a mask made of a plurality of organic films having different thicknesses, patterning the metal layer using the mask to form a source electrode and a drain electrode, and forming the mask after patterning the metal layer And deforming the metal layer by patterning the metal layer using the deformation mask. The semiconductor layer is formed using a connection mask obtained by connecting the mask positioned between the source electrode and the drain electrode to a deformed organic film mask by deforming a mask and connecting the mask. And a step of patterning the TFT substrate. And a step of ohmic layer is formed between the metal layer and the semiconductor layer manufacturing method of T FT substrate according to claim 35 or 36 wherein the ohmic layer is also patterned in the patterning step of the metal layer . A step of forming an ohmic layer between the metal layer and the semiconductor layer, the ohmic layer is also patterned in the patterning step of the semiconductor layer, and the source electrode and the T FT substrate manufacturing method according to claim 35 or 36 for patterning the ohmic layer and the drain electrode as a mask. A step of forming a common electrode on the substrate when forming the gate electrode; and further, the gate so as to cover the common electrode during the step of sequentially forming the gate insulating film, the semiconductor layer, and the metal layer. insulating film, the semiconductor layer, thereby sequentially forming the metal layer includes forming a pixel electrode positioned above the common electrode by patterning the metal layer during the step of forming the source electrode and the drain electrode T FT substrate manufacturing method according to claim 35 or 36. 37. The T according to claim 35 or 36, wherein a thickness of the mask adjacent to each other corresponding to the source electrode and the drain electrode has a thin film region that becomes thinner on a side farther than a thickness on an adjacent side. FT substrate manufacturing method. The TFT substrate according to any one of claims 35 to 39, wherein the step of forming the deformed organic film is performed by a dissolution reflow that causes a chemical solution to penetrate the organic film and causes the organic film to dissolve. Manufacturing method. 40. The method for manufacturing a TFT substrate according to claim 35, wherein the organic film is a photosensitive organic film. 40. The TFT substrate according to claim 35, wherein when the organic film is a photosensitive organic film, the plurality of organic films having different film thicknesses are obtained by changing an exposure amount with respect to the photosensitive organic film. Manufacturing method. 44. The TFT substrate according to any one of claims 41 to 43, wherein the TFT substrate has a thin film region in which a thickness of the adjacent mask corresponding to each of the source electrode and the drain electrode becomes thinner on a side farther than a thickness on an adjacent side. Production method. 45. The method of manufacturing a TFT substrate according to claim 44, wherein the thin film region is removed before forming the connection mask. Forming an organic film having a predetermined pattern on the film to be etched; removing part of the film to be etched from the surface using the organic film as a mask; exposing the film to be etched and the organic film; A step of forming a coating region coated with, a step of removing at least a part of the surface of the organic film, and an organic solvent infiltrated or exposed to the organic film from which at least a part of the surface has been removed, masks and steps, the deformation organic film forming the deformed organic film having an extension is allowed and the predetermined pattern with a different pattern to the exposed area by dissolution reflow causing dissolution of the organic film to deform the organic layer And a step of etching the exposed region of the film to be etched. 47. The pattern forming method according to claim 46, wherein the step of removing at least a part of the surface of the organic film comprises a step of removing a portion including the altered layer on the surface of the organic film. 48. The pattern forming method according to claim 46 or 47, wherein the step of removing at least a part of the surface of the organic film is performed by performing plasma treatment or UV ozone treatment on the organic film. The plasma treatment is O ₂ Plasma processing gas containing gas, Plasma processing gas containing fluorine-based gas, O ₂ 49. The pattern according to claim 48, which is performed using any one of the plasma processing gases including a mixed gas of gas and fluorine-based gas. Forming method. When the plasma processing gas is a plasma processing gas containing a fluorine-based gas, SF ₆ , CF ₄ , CHF ₃ And the plasma processing gas is O. ₂ When it is a plasma processing gas containing a mixed gas of gas and fluorine-based gas, SF ₆ / O ₂ , CF ₄ / O ₂ , CHF ₃ / O ₂ The pattern formation method of Claim 49 containing any gas of these. 48. The pattern forming method according to claim 46, wherein the step of removing at least a part of the surface of the organic film comprises a step of immersing the film to be etched and the organic film in a hydrofluoric acid solution. In the step of forming the organic film, an adjacent organic film adjacent to the organic film is formed, and in the step of forming the deformed organic film, the adjacent organic film becomes an adjacent deformed organic film, and the deformed organic film and 52. The pattern forming method according to any one of claims 46 to 51, wherein the pattern forming method is combined. 53. The pattern according to claim 46, further comprising a step of removing a part of the deformed organic film between the step of forming the deformed organic film and the step of etching an exposed region of the film to be etched. Forming method. The step of removing a part of the deformed organic film is performed by performing an ashing process using oxygen or an ozone process using ultraviolet rays on the deformed organic film to reduce the area of the deformed organic film. 54. The pattern forming method according to claim 53. The process from the step of forming the deformed organic film to the step of etching the exposed region of the etching target film is repeated at least once after the step of etching the exposed region of the etching target film. A pattern forming method according to any one of the above. 56. The pattern forming method according to claim 46, wherein at least the last etching among the etching of the etching target film is performed by wet etching. 57. The pattern forming method according to claim 46, wherein the organic solvent solution includes at least one of the following organic solvents. Organic solvent (R represents an alkyl group or a substituted alkyl group, Ar represents a phenyl group or an aromatic ring other than a phenyl group):
・Alcohols (R-OH)
・Alkoxy alcohols・Ethers (R—O—R, Ar—O—R, Ar—O—Ar)
・Esters, ketones, glycols, alkylene glycols, glycol ethers 58. The pattern forming method according to any one of claims 46 to 57, wherein the dissolution reflow is performed by exposure to vapor of a solution of the organic solvent. 58. The pattern forming method according to any one of claims 46 to 57, wherein the dissolution reflow is performed by immersing in a solution of the organic solvent. 60. The pattern forming method according to any one of claims 46 to 59, wherein the organic film includes a plurality of organic films having different film thicknesses. 61. The pattern forming method according to claim 60, wherein when the organic film is a photosensitive organic film, the plurality of organic films having different film thicknesses are obtained by changing an exposure amount with respect to the photosensitive organic film. The organic film is composed of a plurality of organic films having different thicknesses, and the etched film is partially removed from the surface using the organic film as a mask, and the etched film is covered with the exposed region and the organic film. Between the step of forming a covered region and the step of deforming the organic film to form a deformed organic film extending to the exposed region, the organic film is etched to form the organic film. A step of removing a relatively thin organic film from a plurality of organic films having different thicknesses constituting the film and leaving an organic film thicker than the relatively thin organic film is performed. 62. The pattern forming method according to claim 60 or 61. The film to be etched is composed of a first film and a second film in order from the bottom, and the second film is removed by etching using the organic film as a mask, and the first film is used as a mask for the deformed organic film. 63. The pattern forming method according to claim 46, wherein the pattern is removed by etching. 64. The pattern forming method according to claim 63, wherein the first film is a first metal film, and the second film is a second metal film made of a material different from that of the first metal film. 64. The pattern forming method according to claim 63, wherein the first film is a silicon film, and the second film is an ohmic contact silicon film and a metal film containing impurities at a high concentration in order from the bottom. 64. The pattern forming method according to claim 63, wherein the first film is a silicon film and a silicon film for ohmic contact containing a high concentration of impurities in order from the bottom, and the second film is a metal film. The silicon film constitutes a semiconductor layer of a thin film transistor, the ohmic contact silicon film and the metal film constitute a source electrode and a drain electrode of the thin film transistor, and the organic film is composed of an organic film having a plurality of thicknesses. 67. The organic film according to claim 65 or 66, wherein the organic film includes a thick organic film formed thick on a channel side of the semiconductor layer and a thin organic film formed thin on a side away from the channel of the semiconductor layer. Pattern forming method. After forming the source electrode and the drain electrode of the thin film transistor, the organic film is etched from the surface to leave only the thick film organic film on the source electrode and the drain electrode, and deform the thick film organic film. 68. The pattern forming method according to claim 67, wherein the pattern is a deformed organic film. 69. The pattern forming method according to claim 46, wherein a cross-sectional shape of the film to be etched after etching with the deformed organic film is tapered or stepped. 70. The pattern forming method according to claim 46, wherein the organic film is a resist film. Forming an organic film having a predetermined pattern on the film to be etched; removing part of the film to be etched from the surface using the organic film as a mask ; exposing the film to be etched and the organic film; The organic film is deformed and extended to the exposed region by a step of forming a coated region coated with the substrate and a dissolution reflow that causes the organic film to dissolve or expose by exposing or exposing the organic film to the organic film. a step of the modified organic film having a pattern and different from the predetermined pattern is stationary, the a pattern forming method comprising the step of etching the exposed areas of the film to be etched the deformation organic film as a mask, the organic The film is a pattern forming method comprising a plurality of organic films having different film thicknesses. 72. The pattern forming method according to claim 71, wherein when the organic film is a photosensitive organic film, the plurality of organic films having different film thicknesses are obtained by changing an exposure amount with respect to the photosensitive organic film. The organic film is composed of a plurality of organic films having different thicknesses, and the etched film is partially removed from the surface using the organic film as a mask, and the etched film is covered with the exposed region and the organic film. A plurality of different thicknesses constituting the organic film by etching the organic film between the step of forming the covering region and the step of deforming the organic film to form the deformed organic film extending to the exposed region 73. The pattern according to claim 71 or 72, wherein a step of removing a relatively thin organic film from the organic film to leave a thicker organic film than the relatively thin organic film is performed. Forming method. A step of partially removing the film to be etched from the surface using the organic film as a mask, so that the film to be etched is an exposed region and a coating region covered with the organic film. 68. A step of removing the altered layer on the surface of the organic film is performed between the step of deforming the organic film and forming a deformed organic film extending to the exposed region. A pattern forming method according to any one of the above. 75. The pattern forming method according to claim 71, wherein a cross-sectional shape of the film to be etched after etching with the deformed organic film is tapered or stepped. Forming an organic film having a predetermined pattern on the film to be etched; removing part of the film to be etched from the surface using the organic film as a mask ; exposing the film to be etched and the organic film; A step of forming a coating region coated with, a step of removing at least a part of the surface of the organic film, and an organic solvent infiltrated or exposed to the organic film from which at least a part of the surface has been removed, masks and steps, the deformation organic film forming the deformed organic film having an extension is allowed and the predetermined pattern with a different pattern to the exposed area by dissolution reflow causing dissolution of the organic film to deform the organic layer wherein a pattern forming method comprising the step of etching the exposed areas of the film to be etched as the organic film is composed of a plurality of organic films having different film thickness pattern Down forming method. Forming an organic film having a predetermined pattern on the film to be etched; removing part of the film to be etched from the surface using the organic film as a mask; exposing the film to be etched and the organic film; A step of improving the wettability of the exposed region by performing a process of making the surface of the exposed region of the film to be etched smooth or hydrophilic, and a step of making the organic film by exposing either infiltrating an organic solvent, the organic layer is deformed in different from and said predetermined pattern is extended up to the exposed region of the wettability is improved pattern by dissolution reflow causing dissolution of the organic layer pattern forming method comprising forming a modified organic film, and etching the exposed region of the film to be etched the deformation organic film as a mask with. 78. The pattern forming method according to claim 77, wherein the step of improving the wettability includes a step of immersing the film to be etched in a hydrofluoric acid solution. 78. The pattern forming method according to claim 77, wherein the step of improving the wettability includes a step of performing a surface treatment with plasma or a fluorine-based gas and oxygen. 78. The pattern forming method according to claim 77, wherein the step of improving the wettability includes plasma treatment or UV ozone treatment of the organic film. 81. The pattern forming method according to claim 80, wherein the step of improving wettability includes a step of removing a portion including a deteriorated layer on the surface of the organic film. 78. The pattern forming method according to claim 77, wherein the step of improving the wettability includes a step of immersing the film to be etched and the organic film in a hydrofluoric acid solution. In the step of forming the organic film, an adjacent organic film adjacent to the organic film is formed, and in the step of forming the deformed organic film, the adjacent organic film becomes an adjacent deformed organic film, and the deformed organic film and 83. The pattern forming method according to any one of claims 77 to 82, wherein the pattern forming method is combined. The pattern according to any one of claims 77 to 83, further comprising a step of removing a part of the deformed organic film between the step of forming the deformed organic film and the step of etching the exposed region of the film to be etched. Forming method. The step of removing a part of the deformed organic film is performed by performing an ashing process using oxygen or an ozone process using ultraviolet rays on the deformed organic film to reduce the area of the deformed organic film. 85. The pattern forming method according to claim 84. 86. The process from the step of forming the deformed organic film to the step of etching the exposed region of the etching target film is repeated at least once after the step of etching the exposed region of the etching target film. A pattern forming method according to any one of the above. The etching according to any one of claims 77 to 86, wherein at least the last etching among the etching of the film to be etched is performed by wet etching. The pattern formation method of mounting. The pattern formation method according to any one of claims 77 to 87, wherein the dissolution reflow is performed by exposure to a vapor of a solution of the organic solvent. The pattern formation method according to any one of claims 77 to 88, wherein the dissolution reflow is performed by immersing in a solution of the organic solvent. 90. The pattern forming method according to claim 77, wherein the organic film is formed of a plurality of organic films having different film thicknesses. The pattern forming method according to claim 90, wherein when the organic film is a photosensitive organic film, the plurality of organic films having different film thicknesses are obtained by changing an exposure amount with respect to the photosensitive organic film. The organic film is composed of a plurality of organic films having different thicknesses, and the etched film is partially removed from the surface using the organic film as a mask, and the etched film is covered with the exposed region and the organic film. A plurality of different thicknesses constituting the organic film by etching the organic film between the step of forming the covering region and the step of deforming the organic film to form the deformed organic film extending to the exposed region 92. The pattern formation according to claim 90 or 91, wherein a step of removing a relatively thin organic film from the organic film to leave a thicker organic film than the relatively thin organic film is performed. Method. The film to be etched includes a first film and a second film in order from the bottom, and the second film is removed by etching using the organic film as a mask, and the first film is used as a mask for the deformed organic film. 93. The pattern forming method according to any one of claims 77 to 92, wherein the pattern is removed by etching. 94. The pattern forming method according to claim 93, wherein the first film is a first metal film, and the second film is a second metal film made of a material different from that of the first metal film. 95. The pattern forming method according to claim 94, wherein the first film is a silicon film, and the second film is a silicon film for ohmic contact and a metal film containing impurities at a high concentration in order from the bottom. The pattern formation method according to claim 93, wherein the first film is a silicon film and a silicon film for ohmic contact containing a high concentration of impurities in order from the bottom, and the second film is a metal film. The silicon film constitutes a semiconductor layer of a thin film transistor, the ohmic contact silicon film and the metal film constitute a source electrode and a drain electrode of the thin film transistor, and the organic film is composed of an organic film having a plurality of thicknesses. 97. The organic film comprises a thick organic film formed thick on a channel side of the semiconductor layer and a thin organic film formed thin on a side away from the channel of the semiconductor layer. Pattern forming method. After forming the source electrode and the drain electrode of the thin film transistor, the organic film is etched from its surface, leaving only the thick film organic film on the source electrode and the drain electrode, and deforming the thick film organic film. The pattern forming method according to claim 97, wherein the pattern is a deformed organic film. 99. The pattern forming method according to claim 77, wherein a cross-sectional shape of the film to be etched after etching with the deformed organic film is tapered or stepped. The pattern forming method according to claim 77, wherein the organic film is a resist film. Forming an organic film having a predetermined pattern on the film to be etched; removing part of the film to be etched from the surface using the organic film as a mask; exposing the film to be etched and the organic film; a step of the coated coated region, and forming a modified organic film and having a to extend different from said predetermined pattern pattern up to the exposed area by deforming the organic film, the deformation organic layer Examples mask a pattern forming method comprising the step of etching the etching target film, the step of forming the modified organic film, by exposing either infiltrating an organic solvent in the organic layer, the dissolution of the organic layer pattern forms made by dissolving reflow causing, tapering the cross-sectional shape of the film to be etched after etching by the deformation organic film, or stepwise Method.

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