JP2000150899A - Thin-film formation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the adhesion of an insulating board, a conductive thin film, and a photosensitive resist. SOLUTION: Oxygen plasma treatment is made to the surface of an insulating board 101 before forming a conductive thin film 102 on the board 101. Otherwise, the oxygen plasma treatment is carried out without breaking a vacuum immediately after the formation of the conductive thin film 102 or at the final period of the film-forming process for allowing the surface of the insulating board 101 or the conductive thin film 102 to be subjected to oxidation treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for forming a conductive channel such as a wiring pattern of a semiconductor device, and more particularly to a method for forming a thin film for forming a wiring pattern of a liquid crystal display element using a thin film transistor as a switching element.

[0002]

2. Description of the Related Art In various semiconductor devices such as a thin film transistor (hereinafter, referred to as a TFT), an internal wiring (hereinafter, simply referred to as a wiring or a wiring pattern), which is a conductive flow path, is formed on an insulating substrate (hereinafter, simply referred to as a substrate). ) Is an important factor in reducing the defective rate.

In general, this type of wiring is formed by patterning a conductive thin film formed on a substrate using a mask exposure and development using a photosensitive resist and an etching process, that is, a photolithography technique.

Some of the defects in the wiring are caused by the physical properties of the conductive thin film itself constituting the wiring, such as stress. However, the adhesion of the conductive thin film to the substrate is poor and the photosensitive resist to the conductive thin film is poor. In many cases, the patterning is caused by poor patterning due to poor adhesion.

[0005] The above-mentioned poor adhesion originates from the intrinsic physical properties of the substrate or the conductive thin film and the contamination existing on the surface of the substrate or the conductive thin film. For this reason, processes such as cleaning with various fluids and heating in a vacuum have been conventionally performed before and after the formation of the conductive thin film.

Japanese Patent Application Laid-Open No. 9-162161 discloses that the etching accuracy can be improved by modifying the surface by oxygen plasma ashing before etching a conductive thin film after forming a pattern of a photosensitive resist. Is described.

[0007]

SUMMARY OF THE INVENTION Among the above prior arts,
Although methods of cleaning and heating in a vacuum are very commonly performed, the above-mentioned contamination source cannot be sufficiently removed. In addition, since the method described in Japanese Patent Application Laid-Open No. Hei 9-162161 performs oxygen plasma ashing after forming a resist pattern, it is not clear whether it contributes to the adhesion of the photosensitive resist. .

Further, in the prior art, a method is employed in which the substrate after the formation of the conductive thin film is once taken out of the vacuum chamber, exposed to the air for a certain period of time, and then processed by another apparatus. Therefore, there are concerns about adsorption of impurities in the air on the substrate surface, a decrease in production efficiency due to the use of another device, and problems such as equipment costs.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a method for forming a thin film in which the adhesion between a substrate, a conductive thin film and a photosensitive resist is improved.

[0010]

In order to achieve the above object, the present invention provides a method for performing a surface treatment for improving the adhesion and removing impurities in a manner continuous with a step of forming a conductive thin film by sputtering. It is characterized by the following points.

Hereinafter, a typical configuration of the present invention will be described as follows. (1) When forming a conductive thin film on an insulating substrate, oxygen plasma treatment is performed on the surface of the insulating substrate before forming the conductive thin film, or immediately after or after forming the conductive thin film. At the end of the process, the surface of the insulating substrate or the conductive thin film is oxidized by oxygen plasma treatment without breaking the vacuum.

According to this method, contamination sources such as impurities on the surface of the insulating substrate or the conductive thin film are removed.
In addition, the adhesiveness of the photosensitive resist is improved, the occurrence of wiring defects is significantly reduced, the equipment cost is reduced, and a highly reliable thin film is obtained.

(2) In (1), after forming a conductive thin film on the insulating substrate, immediately after oxidizing in an oxygen plasma atmosphere without breaking vacuum, a photosensitive resist is applied to the conductive thin film. Exposure is performed through an exposure mask having an opening pattern, development and etching are performed to form a wiring pattern of a conductive thin film corresponding to the opening pattern of the exposure mask.

According to this method, in addition to the effect (1), a favorable conductive thin film wiring pattern corresponding to the opening pattern of the exposure mask can be formed.

(3) In (2), immediately after forming the conductive thin film by sputtering in an argon gas atmosphere, the surface of the conductive thin film is oxidized by sputtering in an argon-oxygen mixed gas atmosphere.

According to this method, the adhesion between the insulating substrate and the conductive thin film or between the conductive thin film and the photosensitive resist is improved, and a good conductive thin film pattern can be obtained.

(4) After oxidizing the insulating substrate in an oxygen plasma atmosphere, a conductive thin film is immediately formed without breaking vacuum, a photosensitive resist is applied to the conductive thin film, and an exposure mask having a predetermined opening pattern is formed. Exposed through, developed,
By performing an etching process, a wiring pattern of a conductive thin film corresponding to the opening pattern of the mask is formed.

According to this method, the insulating substrate, the conductive thin film,
Alternatively, the adhesion between the conductive thin film and the photosensitive resist is improved, and a good conductive thin film pattern can be obtained.

(5) In (4), after depositing an oxide layer on the surface of the insulating substrate by sputtering in an argon-oxygen mixed gas atmosphere, the conductive thin film is formed by sputtering in an argon gas atmosphere. Thereafter, an oxide layer is formed on the conductive thin film again by sputtering in an argon-oxygen mixed gas atmosphere.

According to this method, the insulating substrate, the conductive thin film,
Alternatively, the adhesion between the conductive thin film and the photosensitive resist is improved, and a good conductive thin film pattern can be obtained.

As shown in each of the above structures, by performing the formation of the oxide layer on the insulating substrate and the conductive thin film in the same vacuum chamber, the productivity is improved and the equipment cost is reduced.

It should be noted that the present invention is not limited to the above-described configurations and the embodiments described below, and various modifications can be made without departing from the technical idea of the present invention.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to examples.

FIG. 1 is a schematic sectional view for explaining an example of the thin film structure formed in the first embodiment of the thin film forming method according to the present invention. The insulating substrate 101 is a glass substrate, on which a thin film 102 of chromium (Cr), which is a conductive thin film, is formed, and an oxide film 103 of chromium is further formed thereon.

The method for forming the thin film structure is as follows. That is, a long side 830 mm and a short side 650 m cleaned by a washing treatment using a basic solution by a known method.
The glass substrate 101 having a thickness of 0.7 mm and a thickness of 0.7 mm is heated in a vacuum using an infrared lamp to perform degassing.

The heating set temperature is set high within a range that matches the set temperature during film formation. This set temperature is
Typically, it is 373K to 573K.

After that, the glass substrate 101 is carried into a film forming chamber, and a chromium thin film 102 is formed on the glass substrate 101 by sputtering using a chromium target. Subsequently, a mixed gas of argon Ar and oxygen O ₂ is introduced into the film formation chamber to perform a sputtering process, so that an oxide layer (a chromium oxide film) 103 is formed. It is preferable that the glass substrate is carried into the film formation chamber after being heated while keeping a vacuum.

The total thickness of the formed chromium thin film 102 and oxide layer 103 is 300 nm. Further, the conductive thin film is not limited to the above-mentioned chromium, but may be made of another appropriate material.

Thereafter, a photosensitive resist is applied so as to cover the conductive thin film 102 on which the oxide layer 103 is formed, exposed through an exposure mask having a predetermined opening pattern, developed, etched, and A predetermined wiring pattern was obtained through a step of removing the photosensitive resist thus obtained.

FIG. 2 is a schematic sectional view for explaining an example of the structure of a film forming apparatus used for carrying out the first embodiment of the thin film forming method according to the present invention. This apparatus is a general single-wafer type magnetron sputtering apparatus. A substrate mounting table 202 for mounting and holding a glass substrate 101 is installed in a vacuum chamber (film forming chamber) 201. A chromium target 205 is provided at a position facing the chromium.

A vacuum exhaust device (not shown) is connected to the vacuum chamber 201, and gas introduction means 203 is provided. Reference numeral 204 denotes a sputtering power supply.

Here, the power density applied to the target 205 is 30 kW / m ² and the pressure of the process gas is 0.3 P
a, but is not limited to this.

The glass substrate 101 is carried into the vacuum chamber 201 by carrying means (not shown), and is placed on the substrate placing table 202. At this time, the inside of the vacuum chamber 201 is evacuated by a vacuum exhaust device (not shown).

After the vacuum chamber 201 is evacuated, argon (Ar) gas is introduced by the gas introducing means 203 so as to have a predetermined pressure. After the pressure of the argon gas reaches a predetermined value, power is supplied from the power supply 204 to sputter the target 205.

At this time, a magnetic field suitable for magnetron discharge is formed on the surface of the target 205 by a permanent magnet unit (not shown).

By this sputtering process, a chromium thin film 1 was formed.
02 is formed to a predetermined thickness (for example, 290 nm), and then a mixed gas of argon and oxygen is supplied from the gas introducing means 203 so as to have a predetermined pressure.
Is supplied to the target 205 to perform sputtering.

At this time, since oxygen gas is contained in the process gas, oxygen is introduced into the chromium film to be subsequently deposited, and the oxide film 103 is formed. After this oxide film 103 is formed to a predetermined thickness, for example, about 10 nm, the sputtering process is terminated, and the formed glass substrate 101 is carried out of the vacuum chamber by a transfer means (not shown).

Incidentally, the resist adhesion of the conductive thin film forming the wiring pattern depends on the easiness of bonding of atoms on the surface of the conductive thin film. The purpose of forming the oxide layer on the surface of the conductive thin film is to improve the bonding between atoms, that is, the affinity. This affinity can be quantified by the value of the contact angle. Here, the contact angle of pure water was measured and used as a measure of the adhesiveness of the photosensitive resist.

In this embodiment, the contact angle was measured by changing the formation time of the oxide layer 103 and the mixing ratio of the mixed gas of argon gas and oxygen.

FIG. 3 is an explanatory view showing the result of measuring the contact angle of pure water on the surface of the thin film when an oxide film is formed after the chromium film is formed according to the first embodiment of the present invention. The vertical axis represents the processing time t (sec) for forming the contact angle θ (rad).
Take and show. The mixing ratio of the mixed gas is 1 to argon gas.
“Ar-10% O ₂ ” mixed with 0% oxygen gas and “Ar-20 mixed with 20% oxygen gas mixed with argon gas”
% O ₂ "was used. As comparative data, pure Ar is also shown. It can be said that the smaller the contact angle θ, the higher the affinity of the surface, and therefore the higher the resist adhesion.

As shown in FIG.
The effect is also observed in c, and the effect increases as the processing time is extended, and the effect increases as the proportion of oxygen in the mixed gas increases.

In the figure, even when pure Ar is used, the contact angle decreases as the treatment time increases. This is because a new surface was formed by depositing a chromium thin film.
The addition of oxygen to the process gas (processing gas) means that oxygen atoms are further disposed on the surface, thereby improving the adhesion. The black circles indicate the contact angle of the reference sample with the substrate taken out only by the heat treatment.

As described above, according to the present embodiment, the adhesion (resist adhesion) of the conductive thin film to the photosensitive resist is improved, and the occurrence of defects in the wiring pattern due to the subsequent photolithography is significantly reduced. Wiring patterns can be obtained.

FIG. 4 is a schematic sectional view for explaining an example of the thin film structure formed by the second embodiment of the thin film forming method according to the present invention. The insulating substrate 301 is a glass substrate, on which an oxide layer 302 of a chromium-molybdenum alloy is formed, and a thin film 303 of a chromium-molybdenum alloy is formed thereon. Further, an oxide layer 304 of a chromium-molybdenum alloy is formed on the upper layer.

The method for forming this thin film structure is as follows. That is, the glass substrate 301 that has been cleaned in the same manner as in the above embodiment is heated in a vacuum using an infrared lamp to degas.

The glass substrate 301 is carried into a film forming chamber,
On a glass substrate 301, a target of an alloy of chromium (Cr) and molybdenum (Mo) is formed by sputtering with a mixed gas of argon gas and oxygen gas.
An oxide layer 302 of a molybdenum alloy (Cr-Mo) is formed.

Thereafter, pure argon gas is introduced into a sputtering chamber (processing chamber, vacuum chamber) to perform sputtering, and a thin film 303 of a chromium-molybdenum alloy is formed.
Further, subsequently, a mixed gas of argon gas and oxygen gas is introduced into the vacuum chamber to perform sputtering, and the chromium-
An oxide layer 304 of a molybdenum alloy is formed.

It is preferable that the glass substrate is carried into the film forming chamber after being heated while keeping a vacuum.

The total thickness of the formed chromium-molybdenum alloy oxide layer 302, chromium-molybdenum alloy thin film 303, and chromium-molybdenum alloy oxide layer 304 is 300 nm. Further, the conductive thin film is not limited to the chromium-molybdenum alloy described above, but may be made of another appropriate material.

Thereafter, a photosensitive resist is applied so as to cover the oxide layer 304, exposed through an exposure mask having a predetermined opening pattern, developed, etched, and the remaining photosensitive resist is removed. A predetermined wiring pattern was obtained through the steps.

The above-mentioned thin film structure is formed by using the film forming apparatus shown in FIG. 2 in the first embodiment. In this embodiment, a chromium-molybdenum alloy is used as the target 205.

Here, the power density applied to the target 205 is 20 kW / m ² , and the pressure of the process gas is 0.25
Pa, but not limited to this.

The glass substrate 301 is carried into the vacuum chamber 201 by carrying means (not shown), and is placed on the substrate mounting table 202. In this embodiment, the glass substrate 101 in FIG. 2 is replaced with the glass substrate 301). At this time, the vacuum chamber 201
Is evacuated to a vacuum by a vacuum exhaust device (not shown).

After the vacuum chamber 201 is evacuated, a gas mixture of an argon (Ar) gas and an oxygen gas (O ₂ ) is introduced by the gas introducing means 203 so as to have a predetermined pressure. After the pressure of the mixed gas reaches a predetermined value, the power supply 204
And the target 205 is sputtered.
At this time, since oxygen is contained in the process gas, oxygen is introduced into the subsequently deposited chromium-molybdenum alloy film, so that the oxide layer 302 is formed.

A magnetic field suitable for magnetron discharge is formed on the surface of the target 205 by a permanent magnet unit (not shown).

Next, after forming this chromium-molybdenum alloy oxide layer 302 to a predetermined thickness, the gas introducing means 203 is formed.
After introducing pure argon gas from and reaching a predetermined pressure,
The chromium-molybdenum alloy target 205 is sputtered, and a chromium-molybdenum alloy thin film 303 is formed to a predetermined thickness.

Thereafter, a mixed gas of argon and oxygen is supplied from the gas introducing means 203 so as to have a predetermined pressure, and power is continuously supplied from the power supply 204 to the target 205 to perform sputtering.

At this time, since oxygen gas is contained in the process gas, oxygen is introduced into the subsequently deposited chromium-molybdenum alloy film, and an oxide film 304 is formed. After the oxide film 304 is formed to have a predetermined thickness, the sputtering process is terminated, and the formed glass substrate 301 is carried out of the vacuum chamber by a transfer unit (not shown).

Also in this example, the affinity of the surface was evaluated by the contact angle of pure water. In this embodiment, the adhesion of the thin film 303 of chromium-molybdenum alloy to the glass substrate 301 is
The glass substrate 301 after the completion of the formation of the chromium-molybdenum alloy oxide film 302 was taken out of the vacuum chamber and evaluated by measuring the contact angle.

The chromium-molybdenum alloy thin film 30
In order to evaluate the resist adhesion of No. 3, the contact angle after the formation of the chromium-molybdenum alloy oxide film 304 was measured.

FIG. 5 is an explanatory view of the result of measuring the contact angle of pure water on the substrate surface when the lowermost chromium-molybdenum alloy oxide layer 302 according to the second embodiment of the present invention is formed. The axis represents the processing time t (sec) for forming the oxide layer,
The vertical axis shows the contact angle θ (rad). The mixing ratio of the mixed gas is “Ar-20% O ₂ ” and “Ar-40% O ₂ ”
It was used. As comparative data, pure Ar is also shown. It can be said that the smaller the contact angle θ, the higher the affinity of the surface, and therefore the higher the resist adhesion.

As shown in FIG.
The effect is also observed in c, and the effect increases as the processing time is extended, and the effect increases as the proportion of oxygen in the mixed gas increases.

In the figure, even when pure Ar was used, the contact angle decreased as the treatment time increased. This was because a new surface was formed by depositing a thin film of a chromium-molybdenum alloy, and the process gas was used. The addition of oxygen to the (processing gas) means that oxygen atoms are further disposed on the surface, thereby improving the adhesion. The black circles indicate the contact angle of the reference sample with the substrate taken out only by the heat treatment.

FIG. 6 is an explanatory view showing the result of measuring the contact angle of pure water on the surface of the substrate on which the uppermost chromium-molybdenum alloy oxide layer 304 is formed according to the second embodiment of the present invention.

FIG. 6 shows that after forming an oxide layer of a chromium-molybdenum alloy on the glass substrate 301,
A thin film 302 of a molybdenum alloy is formed, and chromium-
In the case where the molybdenum alloy oxide layer is formed, the contact angle tends to be small, similarly to the case where the chromium oxide layer 103 is formed after forming the chromium thin film 102 on the glass substrate 101 of the first embodiment. It turns out that there is.

As described above, according to the present embodiment, the adhesion of the conductive thin film on the glass substrate and the adhesion of the conductive thin film to the photosensitive resist (resist adhesiveness) are improved, and the subsequent photolithography process The occurrence of defects in the wiring pattern is significantly reduced, and a good wiring pattern can be obtained.

FIG. 7 is a schematic sectional view for explaining an example of a thin film structure formed in the third embodiment of the thin film forming method according to the present invention. The insulating substrate 401 is a glass substrate, on which a thin layer 402 of silicon oxide (SiO ₂ ) is formed, and further, a thin film 403 of chromium is formed. Further, a chromium oxide layer 404 is formed on the upper layer.

The method for forming the thin film structure is as follows. That is, the glass substrate 401 cleaned in the same manner as in the above embodiment is heated in a vacuum using an infrared lamp to degas. The glass substrate 401 is carried into a film forming chamber (vacuum chamber). This loading is desirably performed without breaking the vacuum.

The glass substrate 401 is exposed to oxygen plasma in a vacuum chamber to oxidize the surface, thereby forming an oxide layer (in this case, silicon oxide (SiO _x , x ≦ 2)) 402. Next, a chromium thin film 403 is formed over the glass substrate 401 by sputtering using a chromium target. Thereafter, the surface of the glass substrate is again exposed to oxygen plasma to perform an oxidation treatment, and an oxide layer (CrO _x , x ≦ 2) 4
04 is formed. The thickness of the chromium thin film 403 is, for example, 3
00 nm.

An oxide layer 404 exists on the surface of the glass substrate 401 before film formation and on the surface of the chromium thin film 403 after film formation. Further, the conductive thin film material may be other than chromium.

A photosensitive resist is applied by a known method to the glass substrate on which the above-described film forming process has been performed, and a wiring pattern is formed through pattern exposure using an exposure mask, development, etching, and resist removal. .

FIG. 8 is a schematic sectional view for explaining a configuration example of a film forming apparatus used for carrying out a third embodiment of the thin film forming method according to the present invention. This apparatus uses a glass substrate 40
The processing apparatus for oxidizing the surface of the conductive thin film 403 and the surface of the conductive thin film 403 is a general parallel plate type plasma processing apparatus, and the apparatus for forming the conductive thin film 403 is a general single-wafer magnetron sputtering apparatus. It is. That is, the oxidation treatment of the surface and the deposition of the conductive thin film are performed in independent vacuum chambers, respectively, and a transfer chamber is provided between the respective processing chambers, and the transfer of the substrate between the two processing chambers is performed in a vacuum atmosphere. Done without breaking.

First, the glass substrate 401 is placed in the first vacuum chamber 50.
1, and is loaded on the first substrate mounting table 502 by a loading means (not shown). The inside of the first vacuum chamber 501 is evacuated by a vacuum exhaust device (not shown).

Thereafter, oxygen gas is introduced by the gas introduction means 503 so as to have a predetermined pressure. Then, the process gas pressure is set to 100 Pa, and the first power supply 5 is connected to the electrode 505.
Electric power is supplied from the substrate 04 to generate oxygen plasma, and the surface of the glass substrate 401 is oxidized. The pressure of the oxygen gas was set to 100 Pa, but this is arbitrary.

As a result, an oxide layer 402 is formed on the surface of the glass substrate 401. Next, the glass substrate 401 is transferred from the opening / closing door 512 of the first vacuum chamber 501 through the opening / closing door 513 of the second vacuum chamber 506 via the transfer chamber 511 evacuated. Note that a substrate transfer robot 514 is provided in the transfer chamber 511. At this time, the second vacuum chamber 506 is also evacuated to a predetermined vacuum by a vacuum exhaust device (not shown).

The glass substrate 401 carried into the second vacuum chamber 506 is mounted on the second substrate mounting table 507. Thereafter, argon gas is introduced by the gas introduction means 508 so as to have a predetermined pressure.

The power density applied from the second power supply 509 to the target 510 is 30 kW / m ² , and the process gas pressure is 0.2 Pa. The pressure of this argon gas is 0.2P
a, which is optional. The input power density can also be arbitrarily set by those skilled in the art.

After the pressure of the argon gas reaches a predetermined value, power is supplied from the second power source 509 to the chromium target 510 to sputter the target. At this time, a magnetic field suitable for magnetron discharge is formed on the surface of the target 510 by a permanent magnet unit (not shown).

After the chromium thin film 403 is formed to a predetermined thickness, the glass substrate 401 is carried again into the first vacuum chamber 501 while maintaining a vacuum through the transfer chamber 511. Then, an oxide layer (chromium oxide layer) 404 is formed on the chromium thin film 403 in the same manner as the formation of the oxide layer 402.

After the formation of the oxide layer 404, the glass substrate 401 is carried out of the vacuum chamber 501 by a transport means (not shown). In addition, the first of the above-mentioned glass substrate 401
The transfer into or out of the vacuum chamber 501 may be performed via the transfer chamber 511.

The adhesion of the thin film formed in this embodiment was also evaluated by the affinity with the contact angle of pure water as in the above embodiment. That is, in this embodiment, as the evaluation of the adhesion of the chromium thin film 403 to the glass substrate 401, the oxide layer 402
Was formed, the glass substrate 401 was taken out and its contact angle was measured.

FIG. 9 is an explanatory diagram of the result of measuring the contact angle of pure water when the surface of the glass substrate is oxidized. As can be seen from this figure, even when the processing time is 20 seconds, the contact angle is reduced, that is, the effect of improving the adhesion is recognized, and this effect is increased as the processing time is extended.

FIG. 10 is an explanatory diagram of the result of measuring the contact angle of pure water when a conductive thin film is formed on the surface of a glass substrate and then oxidized. As can be seen from this figure, as in the first embodiment, even when the processing time is 20 sec, the contact angle is reduced, that is, the effect of improving the adhesion is recognized, and this effect is increased as the processing time is extended.

As described in each of the above embodiments, the adhesion of the conductive thin film to the substrate and the adhesiveness of the photosensitive resist to the conductive thin film are greatly improved, and a good conductive thin film pattern can be obtained.

FIG. 11 is a plan view for explaining the structure of one pixel of an active matrix type liquid crystal display device to which the present invention is applied and the periphery thereof. Each pixel is located within an intersection region (four lines) between two adjacent scanning signal lines (gate signal lines or horizontal signal lines) GL and two adjacent video signal lines (drain signal lines or vertical signal lines) DL. (In a region surrounded by signal lines).

Each pixel includes a thin film transistor TFT, a transparent pixel electrode ITO1, and a storage capacitor Cadd. The scanning signal lines GL extend in the column direction, and a plurality of the scanning signal lines GL are arranged in the row direction. The video signal lines DL extend in the row direction, and a plurality of video signal lines DL are arranged in the column direction.

The thin film transistor TFT of each pixel is divided into two (a plurality) in the pixel, and is constituted by thin film transistors (divided thin film transistors) TFT1 and TFT2. Thin film transistor TFT1 and TFT
Each of the two has substantially the same size (channel length and channel width are the same). Each of the divided thin film transistors TFT1 and TFT2 is
The semiconductor device includes a gate electrode GT, an i-type (intrinsic, intrinsic, and undoped conductivity type determining impurity) i-type semiconductor layer AS made of amorphous silicon (Si), and a pair of source electrode SD1 and drain electrode SD2. The source,
It should be understood that the drain is originally determined by the bias polarity between them, and in the circuit of this liquid crystal display device, the polarity is inverted during operation, so that the source and drain are switched during operation. However, in the following description, for convenience, one is fixed as a source and the other is fixed as a drain.

The gate electrode GT is a thin film transistor TFT
1 and project beyond the respective active areas of the TFT2. The respective gate electrodes GT of the thin film transistors TFT1 and TFT2 are formed continuously. Here, the gate electrode GT is formed of a single-layer second conductive film g2.

The scanning signal line GL is composed of the second conductive film g2. The second conductive film g2 of the scanning signal line GL is formed in the same manufacturing process as the second conductive film g2 of the gate electrode GT, and is formed integrally.

The transparent pixel electrode ITO1 forms one of the pixel electrodes of the liquid crystal panel. The transparent pixel electrode ITO1 is connected to both the source electrode SD1 of the thin film transistor TFT2 and the source electrode SD1 of the thin film transistor TFT2. Therefore, the thin film transistors TFT1, TFT1
Even if a defect occurs in one of the two, if the defect causes a side effect, an appropriate portion is cut by a laser beam or the like; otherwise, the other thin film transistor is operating normally and is left alone. I just need. It is rare that defects occur simultaneously in the two thin film transistors TFT1 and TFT2, and the probability of occurrence of point defects and line defects can be extremely reduced by such a redundant system.

The transparent pixel electrode ITO1 is constituted by the first conductive film d1. This first conductive film d1 is a transparent conductive film (Indium-Tin) formed by sputtering.
-Oxide ITO: Nesa film)
A film thickness of 2000 ° ((1400 in this liquid crystal display device)
(Å film thickness).

A plurality of divided thin film transistors TFT
1. The respective source electrode SD1 and drain electrode SD2 of the TFT2 are provided separately from each other on the i-type semiconductor layer AS.

Note that the color filter FIL and the black matrix BM are formed on the counter substrate side, and their positions are shown in FIG.

FIG. 12 is an exploded perspective view for explaining the overall structure of a liquid crystal display device incorporating a liquid crystal display panel using a substrate whose wiring pattern is manufactured by the thin film forming method of the present invention. , A backlight, and a specific structure of a module (referred to as MDL) in which other components are integrated.

SHD is a shield case (also called a metal frame) made of a metal plate, WD is a display window, INS1
To 3 are insulating sheets, PCB1 to 3 are circuit boards (PCB1
Is a drain side circuit board: a video signal line driving circuit board, P
CB2 is a gate side circuit board, PCB3 is an interface circuit board), JN1 to 3 are joiners for electrically connecting the circuit boards PCB1 to 3, TCP1 and TCP2 are tape carrier packages, PNL is a liquid crystal display panel, G
C is a rubber cushion, ILS is a light shielding spacer, PRS is a prism sheet, SPS is a diffusion sheet, GLB is a light guide plate, RFS is a reflection sheet, MCA is a lower case (mold frame) formed by integral molding, MO is MC
A opening, LP is fluorescent tube, LPC is lamp cable, G
B denotes a rubber bush that supports the fluorescent tube LP, BAT denotes a double-sided adhesive tape, BL denotes a backlight made of a fluorescent tube, a light guide plate, and the like, and is composed of the fluorescent tube LP, a reflection sheet LS, and a light guide plate GLB. Then, the liquid crystal display module MDL is assembled by stacking the diffusion plate members in the arrangement shown in the drawing.

The liquid crystal display module MDL has two kinds of storage / holding members of a lower case MCA and a shield case SHD, and includes insulating sheets INS1 to INS3 and circuit boards PCB1 to PCB1.
3. A metal shield case SHD in which the liquid crystal display panel PNL is stored and fixed, a backlight BL including a fluorescent tube LP, a light guide plate GLB, a prism sheet PRS, and the like. The shield case SHD and the lower case MCA It is pinched and fixed.

An integrated circuit chip for driving each pixel of the liquid crystal display panel PNL is mounted on the video signal line driving circuit board PCB1, and the interface circuit board PC
The B3 includes an integrated circuit chip that receives a video signal from an external host, receives a control signal such as a timing signal, and a timing converter TCON that processes a timing to generate a clock signal.

The clock signal generated by the timing converter is integrated on the video signal line driving circuit board PCB1 via the clock signal line CLL laid on the interface circuit board PCB3 and the video signal line driving circuit board PCB1. Supplied to the circuit chip.

The interface circuit board PCB3 and the video signal line driving circuit board PCB1 are multilayer wiring boards, and the clock signal line CLL is the interface circuit board PCB3 and the video signal line driving circuit board PC
It is formed as an inner wiring of B1.

The liquid crystal display panel PNL is formed by laminating a TFT substrate on which TFTs and various wirings / electrodes are formed, and a filter substrate on which a color filter is formed, and sealing a liquid crystal in a gap therebetween. , A TFT-side circuit board PCB1, a gate-side circuit board PCB2, and an interface circuit board PCB3 for driving TFTs are connected by tape carrier packages TCP1 and TCP2, and the circuit boards are connected by joiners JN1, JN2, JN3. .

In this liquid crystal display device, since the wiring pattern of the liquid crystal display panel PNL is formed well, high reliability and high quality image display can be obtained.

The present invention is not limited to the formation of the wiring pattern of the liquid crystal display panel constituting the liquid crystal display device described above, but can be similarly applied to the formation of electrodes or wiring patterns of other semiconductor devices.

[0103]

As described above, according to the present invention,
When forming a conductive thin film such as a wiring pattern on an insulating substrate, the adhesion between the insulating substrate and the conductive thin film and between the conductive thin film and the photosensitive resist is improved, and a highly reliable conductive thin film pattern free from patterning defects is formed. Can be formed.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view illustrating an example of a thin film structure formed in a first embodiment of a thin film forming method according to the present invention.

FIG. 2 is a schematic cross-sectional view illustrating a configuration example of a film forming apparatus used for performing a first embodiment of a thin film forming method according to the present invention.

FIG. 3 is an explanatory diagram of a result of measuring a contact angle of pure water on a thin film surface when an oxide film is formed after forming a chromium film according to the first embodiment of the present invention.

FIG. 4 is a schematic cross-sectional view illustrating an example of a thin film structure formed by a thin film forming method according to a second embodiment of the present invention.

FIG. 5 is an explanatory diagram illustrating a result of measuring a contact angle of pure water on a substrate surface when a lowermost chromium-molybdenum alloy oxide layer is formed according to a second embodiment of the present invention.

FIG. 6 is an explanatory view illustrating a result of measuring a contact angle of pure water on a surface of a thin film of a chromium-molybdenum alloy having an uppermost chromium-molybdenum alloy oxide layer according to a second embodiment of the present invention.

FIG. 7 is a schematic sectional view illustrating an example of a thin film structure formed in a third embodiment of the thin film forming method according to the present invention.

FIG. 8 is a schematic cross-sectional view illustrating a configuration example of a film forming apparatus used for carrying out a third embodiment of the thin film forming method according to the present invention.

FIG. 9 is an explanatory diagram of a result of measuring a contact angle of pure water when a surface of a glass substrate is oxidized.

FIG. 10 is an explanatory diagram of a result of measuring a contact angle of pure water when a conductive thin film is formed on the surface of a glass substrate and then subjected to an oxidation treatment.

FIG. 11 is a plan view illustrating a configuration of one pixel of an active matrix type liquid crystal display device to which the present invention is applied and the periphery thereof.

FIG. 12 is an exploded perspective view illustrating an overall configuration of a liquid crystal display device incorporating a liquid crystal display panel using a substrate whose wiring pattern is manufactured by the thin film forming method of the present invention.

[Explanation of symbols]

 101 Insulating substrate (glass substrate) 102 Conductive thin film 103 Oxide film.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02F 1/136 500 G02F 1/136 500 H01L 21/285 H01L 21/285 S 21/3205 21/88 M 21 / 336 29/78 616K 617J (72) Inventor Toshiki Kaneko 3300 Hayano, Mobara-shi, Chiba F-term (reference) 2H092 GA16 GA25 GA64 HA06 JA24 MA05 MA10 MA15 MA17 MA23 MA37 NA12 NA18 NA29 PA05 PA06 PA08 PA09 PA12 PA13 4K029 AA09 AA24 BA07 BA22 BB01 BC03 BD01 CA05 DC03 DC04 DC40 FA07 GA03 HA07 4M104 AA09 BB04 BB16 BB36 DD21 DD37 DD39 DD42 DD86 DD89 HH08 5F033 GG04 HH07 HH22 HH35 MM05 MM08 PP15 PP16 QQ73 QQ85 QQ89 QQ91 XX12 XX13 5F110 AA30 DD02 DD12 DD13 DD24 QQ09

Claims (5)

[Claims] 1. A thin film forming method for forming a conductive thin film on an insulating substrate, wherein the surface of the insulating substrate is subjected to oxygen plasma treatment before forming the conductive thin film, A method for forming a thin film, comprising: performing oxygen plasma treatment immediately after film formation or at the end of the film formation process without breaking vacuum to oxidize the surface of the insulating substrate or the conductive thin film. 2. After forming a conductive thin film on an insulating substrate, immediately oxidize in an oxygen plasma atmosphere without breaking vacuum, apply a photosensitive resist to the conductive thin film, and expose the conductive thin film with a predetermined opening pattern. A thin film forming method comprising: exposing through a mask, developing, and etching to form a conductive thin film wiring pattern corresponding to the opening pattern of the mask. 3. The method according to claim 2, wherein the surface of the conductive thin film is oxidized by sputtering in an argon-oxygen mixed gas atmosphere immediately after the formation of the conductive thin film by sputtering in an argon gas atmosphere. The method for forming a thin film according to the above. 4. An insulating substrate is oxidized in an oxygen plasma atmosphere, and then a conductive thin film is immediately formed without breaking vacuum.
A photosensitive resist is applied to the conductive thin film, exposed through an exposure mask having a predetermined opening pattern, developed, and etched to form a wiring pattern of the conductive thin film according to the opening pattern of the mask. A thin film forming method. 5. An oxide layer is deposited on the surface of the insulating substrate by sputtering in an argon-oxygen mixed gas atmosphere, and then the conductive thin film is formed by sputtering in an argon gas atmosphere. The method according to claim 4, wherein an oxide layer is formed on the conductive thin film by sputtering in a gas atmosphere.