KR20100067119A - Indium oxide transparent conductive film and method for producing the same - Google Patents

Abstract

Disclosed is a transparent conductive film which is formed as an amorphous film by using a sputtering target containing an oxide sintered body which contains indium oxide, and if necessary tin, while containing not less than 0.00001 mole but less than 0.10 mole of barium per 1 mole of indium. This transparent conductive film is characterized by containing barium while also containing indium oxide, and if necessary tin. This transparent conductive film is also characterized by being formed under such a condition that the partial pressure of water is not less than 1.0 x 10Pa but not more than 1.0 x 10Pa.

Description

Indium oxide transparent conductive film and its manufacturing method {INDIUM OXIDE TRANSPARENT CONDUCTIVE FILM AND METHOD FOR PRODUCING THE SAME}

The present invention can be formed as an amorphous film, the amorphous film can be easily patterned by weak acid etching, can be easily crystallized, and the crystallized film is a low resistance and high transparent conductive film. And to a method for producing the same.

Indium oxide-tin oxide (composite oxide of In ₂ O ₃ -SnO ₂ , hereinafter referred to as "ITO") film has high visible light transmittance and high conductivity, and thus a heat conductive film for preventing condensation of a liquid crystal display device or glass as a transparent conductive film. Although widely used for infrared reflecting films and the like, there is a problem that it is difficult to form an amorphous film.

On the other hand, as an amorphous film, an indium zinc oxide (IZO) transparent conductive film is known, but such a film has a problem of being inferior in transparency to an ITO film and becoming yellowish.

Therefore, the present applicant has previously proposed an amorphous amorphous conductive film formed by adding silicon to an ITO film as a transparent conductive film and formed under predetermined conditions (see Patent Document 1). However, when silicon is added, there is a tendency of high resistance. There was a problem.

Patent Document 1: Japanese Patent Application Laid-Open No. 2005-135649 (claims)

In view of such circumstances, the present invention can be formed as an amorphous film, and the amorphous film can be easily patterned by weak acid etching, can be easily crystallized, and the crystallized film has low resistance and An object of the present invention is to provide a transparent conductive film having a high transmittance and a method of manufacturing the same.

In order to solve the above-mentioned problems, the present invention has been repeatedly studied. As a result, an indium oxide-based transparent conductive film containing barium is an amorphous film having low resistance and excellent transparency, and can be easily patterned by weak acid etching. Furthermore, it discovered that it could crystallize easily, and applied for it previously (Japanese Patent Application No. 2007-095783).

Also in this case, regarding the composition range whose crystallization temperature is 100 degrees C or less, although there existed the subject that conditions were severe in order to form into a film of an amorphous force, this invention also solves the said subject.

The 1st aspect of this invention which solves the said subject is Amorphous using the sputtering target provided with the oxide sinter which contains indium oxide and tin, and contains 0.00001 mol or more and less than 0.10 mol with respect to 1 mol of indium. A transparent conductive film formed as a film of the film, which contains indium oxide and tin, contains barium, and is formed under a condition in which a partial pressure of water is 1.0 × 10 ⁻⁴ Pa or more and 1.0 × 10 ⁻¹ Pa or less. It is in a transparent conductive film.

In this first aspect, by forming an indium oxide-based transparent conductive film containing barium under a predetermined water pressure, the film can be formed as an amorphous film relatively easily and can be etched into a weakly acidic etchant.

The 2nd aspect of this invention is a transparent conductive film as described in a 1st aspect WHEREIN: The film of the said amorphous force contains hydrogen, The transparent conductive film characterized by the above-mentioned.

In this second aspect, hydrogen is absorbed into the amorphous film by the film formation with a high water pressure.

According to a third aspect of the present invention, in the transparent conductive film according to the first or second aspect, the molar ratio y of tin to 1 mol of indium is represented by the molar ratio x of barium to 1 mol of indium (-6.9 × 10 ⁻² Ln (x) −1.6 × 10 ⁻¹ ) or less and within the range of (−8.1 × 10 ⁻³ Ln (x) + 1.8 × 10 ⁻¹ ) It is in the conductive film.

In this third aspect, an amorphous film has a relatively low crystallization temperature.

According to a fourth aspect of the present invention, in the transparent conductive film according to the first or second aspect, the molar ratio y of tin to 1 mol of indium is represented by the molar ratio x of barium to 1 mol of indium (-8.1 × 10 ⁻² Ln (x) −2.6 × 10 ⁻¹ ) or less and within the range of (−7.1 × 10 ⁻³ Ln (x) + 1.6 × 10 ⁻¹ ) It is in the conductive film.

In this fourth aspect, the film is formed as an amorphous film relatively easily, and etching with a weakly acidic etchant is possible.

A fifth aspect of the present invention is the transparent conductive film according to the fourth aspect, wherein a partial pressure of water is formed under a condition of 1.0 × 10 ⁻³ Pa or more and 1.0 × 10 ⁻¹ Pa or less. .

In this fifth aspect, the film is formed under a predetermined water pressure to form a film having a predetermined range of composition and a relatively low crystallization temperature.

A sixth aspect of the present invention is a transparent conductive film according to any one of the first to fifth aspects, wherein the transparent conductive film is a crystallized film after annealing.

In this sixth aspect, after the film is formed as an amorphous film, crystallization can be easily performed by annealing, and weak acid resistance can be imparted.

A seventh aspect of the present invention is the transparent conductive film according to the sixth aspect, wherein the annealing is performed at 100 to 300 ° C.

In this seventh aspect, a film is crystallized at a relatively low temperature.

An eighth aspect of the present invention is the transparent conductive film according to the sixth or seventh aspect, wherein the resistivity of the transparent conductive film after annealing is 5.0 × 10 ⁻⁴ Ω · cm or less.

In this eighth aspect, the resistivity after annealing is very low, and the resistivity can be set to a low resistance film having 5.0 × 10 ⁻⁴ Ω · cm or less.

A ninth aspect of the present invention uses an indium oxide and tin containing a sputtering target having an oxide sintered body containing indium oxide and tin and containing barium in an amount of 0.00001 mol or more and less than 0.10 mol with respect to 1 mol of indium. In addition, when forming a film of amorphous and containing barium, the partial pressure of water at the time of film formation is 1.0 * 10 <^-4> Pa or more and 1.0 * 10 <^-1> Pa or less, The manufacturing method of the transparent conductive film characterized by the above-mentioned.

In this ninth aspect, by forming a barium-containing transparent conductive film containing barium under a predetermined water pressure, a film can be formed relatively easily as an amorphous film and can be etched into a weakly acidic etchant.

In the tenth aspect of the present invention, in the method for producing a transparent conductive film according to the ninth aspect, the molar ratio y of tin to 1 mol of indium is represented by the molar ratio x of barium to 1 mol of indium (-6.9 Using a sputtering target that is less than or equal to the value of × 10 ⁻² Ln (x) −1.6 × 10 ⁻¹ ) and less than or equal to the value of (−8.1 × 10 ⁻³ Ln (x) + 1.8 × 10 ⁻¹ ) It is a manufacturing method of the transparent conductive film characterized by forming into a film.

In this tenth aspect, a film having a relatively low crystallization temperature can be obtained by setting the composition in a predetermined range.

In the eleventh aspect of the present invention, in the method for producing a transparent conductive film according to the ninth aspect, the molar ratio y of tin to 1 mol of indium is represented by the molar ratio x of barium to 1 mol of indium (-8.1 × 10 ^-2 Ln (x) is less than the value of -2.6 × 10 ^-1) also uses ^{(-7.1 × 10 -3 Ln (x} ) + 1.6 × 10 -1 sputtering within the following range of values) and the target And the partial pressure of water at the time of film-forming is formed into 1.0 * 10 <^-3> or more and 1.0 * 10 <^-1> Pa or less, The manufacturing method of the transparent conductive film characterized by the above-mentioned.

In this eleventh aspect, a film having a relatively low crystallization temperature can be obtained by forming a film having a predetermined composition under a predetermined water pressure.

A twelfth aspect of the present invention is the method for producing a transparent conductive film according to any one of the ninth to eleventh aspects, wherein the film is crystallized by annealing after forming an amorphous film, followed by annealing. Is in.

In this twelfth aspect, after film formation as an amorphous film, crystallization can be easily carried out by annealing to impart weak acid resistance.

A thirteenth aspect of the present invention is the method for producing a transparent conductive film according to the twelfth aspect, wherein the crystallization by annealing is performed at 100 to 300 ° C.

In this thirteenth aspect, a film crystallized at a relatively low temperature at 100 to 300 ° C can be obtained.

A fourteenth aspect of the present invention is the method for producing a transparent conductive film according to the thirteenth aspect, wherein the resistivity of the transparent conductive film after annealing is 5.0 × 10 ⁻⁴ Ω · cm or less.

In this 14th aspect, the resistivity after annealing is very low, and it can be set as the low resistance film whose resistivity is 5.0x10 <^{-4> (} ohm) * cm or less.

According to the present invention, it is a film in which barium is added to indium oxide and formed under a predetermined water pressure, whereby the film can be formed as an amorphous film, and the amorphous film can be easily patterned by weak acid etching. The crystallized film can be easily crystallized, and the crystallized film can provide a transparent conductive film having low resistance and high transmittance.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the crystallization temperature of Test Examples A1-A74 of this invention.
2 is a view showing the crystallization temperature of Test Examples B1 to B74 of the present invention.
3 is a view showing a change in the optimum oxygen partial pressure of Reference Test Examples C1 to C74 of the present invention.

(The best mode for carrying out the invention)

The sputtering target for transparent conductive films used for forming the indium oxide transparent conductive film of the present invention is an oxide sintered body mainly containing indium oxide, containing tin, and containing barium, while barium remains the oxide. Or as a complex oxide or solid solution, and is not particularly limited.

It is preferable to make content of barium into the range formed using the sputtering target contained 0.00001 mol or more and less than 0.10 mol with respect to 1 mol of indium. If it is less than this, the effect of addition is not remarkable, and if it is more than this, it will become a tendency for the resistance of the transparent conductive film formed to become high and a tendency for yellow light to deteriorate. In addition, the barium content in the transparent conductive film formed of said sputtering target becomes content similar to content in the used sputtering target.

Moreover, it is preferable to form into a film using the sputtering target contained in content of tin with respect to 1 mol of indium, 0.001-0.3 mol, Preferably it is 0.005-0.3 mol. If it is in this range, the density and mobility of the carrier electrons of a sputtering target can be controlled suitably, and electroconductivity can be maintained in a favorable range. Moreover, when it adds beyond this range, since it reduces the mobility of the carrier electron of a sputtering target, and acts in the direction which degrades electroconductivity, it is unpreferable. In addition, content of tin in the transparent conductive film formed of said sputtering target becomes content similar to content in the used sputtering target. The compositional analysis of such an indium oxide transparent conductive film may be performed by dissolving the entire amount of the single film and analyzing it by ICP. In the case where the film itself has an element configuration, the cross section of the corresponding portion may be cut out by FIB or the like if necessary, and an elemental analysis device (EDS, WDS, ozer analysis, etc.) attached to the SEM or TEM may be used. It is possible to specify.

Since the sputtering target has a resistance value that can be sputtered by DC magnetron sputtering, sputtering is possible with relatively inexpensive DC magnetron sputtering, but of course, a high frequency magnetron sputtering device may be used.

By using such a sputtering target for transparent conductive films and forming a film under the conditions of a partial pressure of water of 1.0 × 10 ^-4 Pa or more and 1.0 × 10 ^-1 Pa or less, an amorphous indium oxide transparent conductive film can be formed in the same composition. have.

Here, in order to make the partial pressure of water into the above-mentioned predetermined range, it is an atmospheric gas (generally Ar and a gas containing oxygen as needed, for example) which is introduce | transduced into film-forming chamber at the time of film-forming, for example, the pressure of ^10-4 Pa bands. Water vapor may be introduced through a mass flow controller or the like, and in the case of a high vacuum with an attained vacuum of less than 10 ⁻⁴ Pa, the pressure is preferably about 1/100 to 1/10 of the atmospheric gas. In addition, under conditions where the degree of vacuum is poor at about 10 ⁻⁴ to 10 ⁻³ Pa, the main component of the residual gas is water. That is, since the attained vacuum degree is almost corresponded to the partial pressure of water, the state of the desired partial pressure of water can be obtained without introduce | transducing steam specially.

Since the indium oxide-based transparent conductive film of the present invention contains a predetermined amount of barium, depending on the content of barium, the film is formed at a temperature higher than room temperature and lower than the crystallization temperature, for example, lower than 200 ° C. Preferably, the film is formed in an amorphous shape by performing at a temperature lower than 150 ° C, more preferably lower than 100 ° C. In addition, such an amorphous film has an advantage of being able to be etched with a weakly acidic etchant. Here, in this specification, an etching is included in a patterning process and is for obtaining a predetermined pattern.

Moreover, although the resistivity of the obtained transparent conductive film changes with content of barium, resistivity is 1.0 * 10 <^-4> -1.0 * 10 <^{-3> (} ohm) * cm.

Moreover, the crystallization temperature of the film formed into a film changes with content of barium contained, and it rises as content increases, but can crystallize by annealing on the temperature conditions of 100 degreeC-300 degreeC. Since such a temperature range is used in a conventional semiconductor manufacturing process, it may be crystallized in such a process. Moreover, it is preferable to crystallize at 100 degreeC-300 degreeC among this temperature range, It is more preferable to crystallize at 150 degreeC-250 degreeC, It is most preferable to crystallize at 200 degreeC-250 degreeC.

Here, annealing means heating to a desired temperature for a predetermined time in the atmosphere, in an atmosphere, in a vacuum, or the like. Although the fixed time is generally about several hours to several hours, industrially, if the effect is the same, a short time is preferable.

Here, the transparent conductive film of this invention can form an amorphous film by setting partial pressure of water on the conditions of 1.0 * 10 <^-4> Pa or more and 1.0 * 10 <^-1> Pa or less, even if film-forming temperature is set somewhat high.

Here, whether or not the film can be formed as an amorphous film needs to be formed at a film formation temperature lower than the crystallization temperature in the composition of the film to be formed as described above, and the smaller the content of tin or barium, the higher the crystallization temperature. The lower the content of tin and barium, the higher the crystallization temperature. However, by forming a partial pressure of water under the conditions of 1.0 × 10 ^-4 Pa or more and 1.0 × 10 ^-1 Pa or less, the crystallization temperature of each composition is increased. It can be made about 50-100 degreeC high compared with the case of forming into a partial pressure below 1.0 * 10 <^-4> Pa. Therefore, when the partial pressure of water is formed at less than 1.0 × 10 ⁻⁴ Pa, the crystallization temperature is less than 100 ° C., especially for a film having a composition range close to room temperature, the film forming conditions for obtaining an amorphous film become quite severe. In some cases, crystallization may occur during film formation. In such a composition range, since the crystallization temperature can be raised about 150-200 degreeC especially by making partial pressure of water into 1.0 * 10 <^-4> Pa or more and 1.0 * 10 <^-1> Pa or less, for example, Even in the film forming conditions of about 100 ° C., an amorphous film can be obtained.

On the other hand, the crystallization temperature when the partial pressure of water is formed below 1.0 × 10 ⁻⁴ Pa is, for example, in the composition range of 300 ° C. to 400 ° C., the partial pressure of water is 1.0 × 10 ⁻⁴ Pa or more and 1.0 × 10 ^−1. Under the conditions of Pa or less, the crystallization temperature becomes high, for example, 350 to 500 ° C, and even if the amorphous film can be formed, the conditions for crystallization on the contrary become strict. In this case, the partial pressure of water is 1.0 ×. It is not preferable to set it as the conditions of 10 <^-4> Pa or more and 1.0 * 10 <^-1> Pa or less.

Therefore, from this point of view, as the composition of the film which is formed under the condition of the partial pressure of water of 1.0 × 10 ⁻⁴ Pa or more and 1.0 × 10 ⁻¹ Pa or less, the molar ratio y of tin to 1 mol of indium is equal to that of barium to 1 mol of indium. Value of (-6.9 × 10 ⁻² Ln (x) −1.6 × 10 ⁻¹ ) expressed by the molar ratio (x) and less than (−8.1 × 10 ⁻³ Ln (x) + 1.8 × 10 ⁻¹ ) It is preferable to set it as the following ranges. If it is this range, crystallization temperature will be 100-300 degreeC, and it will become comparatively easy to form a film of an amorphous force, crystallize, and use.

In particular, when the film is formed with a partial pressure of water of 1.0 × 10 ⁻³ or more and 1.0 × 10 ⁻¹ Pa or less, the molar ratio (y) of tin to 1 mol of indium is the molar ratio (x) of barium to 1 mol of indium. It is less than or equal to the value of (-8.1 x 10 ^-2 Ln (x) -2.6 x 10 ^-1 ) and is represented by (-7.1 x 10 ^-3 Ln (x) + 1.6 x 10-1). It is preferable to set it as a composition. If it is this range, crystallization temperature will be 100-300 degreeC and it will become comparatively easy to form a film of an amorphous force, crystallize, and to use.

When the partial pressure of water is lower than 1.0 × 10 ⁻⁴ Pa, the effect of raising the crystallization temperature as described above is not remarkable, while on the other hand, when the partial pressure of water is larger than the upper limit (1.0 × 10 ⁻¹ Pa), it is obtained. Although the film is amorphous, the specific resistance of the film does not decrease when annealed and crystallized, and a crystallized film of 5.0 × 10 ⁻⁴ Ω · cm or less is difficult to be obtained, which is not preferable.

Next, although the manufacturing method of the sputtering target used by this invention is demonstrated, this is only illustrated and the manufacturing method is not specifically limited.

First, starting materials constituting the sputtering target of the present invention are generally powders of In ₂ O ₃ , SnO ₂ , and BaCO ₃ , but In ₂ O ₃ and BaCO ₃ are preliminarily plasticized to BaIn ₂ O ₄ , where In is to use a mixture of ₂ O ₃ and SnO ₂ are preferred. This is to prevent the generation of pores due to gas generation by decomposition of BaCO ₃ . Moreover, you may use these single substance, a compound, complex oxide, etc. as a raw material. In the case of using a single element or a compound, a process such as making an oxide in advance is performed.

The method of mixing and molding these raw material powders at a desired blending ratio is not particularly limited, and conventionally known various wet methods or dry methods can be used.

As a dry method, the cold press method, the hot press method, etc. are mentioned. In the cold press method, a mixed powder is filled into a molding die, a molded article is produced, and fired. In the hot press method, the mixed powder is fired and sintered in a molding die.

As the wet method, for example, it is preferable to use a filtration molding method (see Japanese Patent Application Laid-Open No. H11-286002). The filtration molding method is a filtration molding mold made of a water-insoluble material for depressurizing and draining water from a ceramic raw material slurry to obtain a molded body. The filtration molding method includes a molding lower mold having at least one drain hole and a lower mold for mounting on the molding lower mold. It consists of a filter having water permeability, and a molding mold sandwiched from the upper surface side through a sealing member for sealing the filter, and assembled to disassemble the lower mold, the molding mold, the sealing member, and the filter, respectively. A slurry comprising a mixed powder, ion-exchanged water and an organic additive is prepared by using a filtration type mold in which water in the slurry is drained under reduced pressure only from the filter face side, and the slurry is injected into the filtration type mold, and the filter The molded product was produced by depressurizing and draining water in the slurry only from the surface side, and after drying and degreasing the obtained ceramic molded product, Sung.

The baking temperature of the thing molded by the cold press method or the wet method is 1300-1650 degreeC, More preferably, it is 1500-1650 degreeC, The atmosphere is an atmospheric atmosphere, an oxygen atmosphere, a non-oxidizing atmosphere, or a vacuum atmosphere. On the other hand, in the hot press method, it is preferable to sinter at 1200 degreeC, The atmosphere is a non-oxidizing atmosphere, a vacuum atmosphere, etc. In addition, after baking by each method, the machining for shaping | molding and processing to a predetermined dimension is made into a target.

(Example)

EMBODIMENT OF THE INVENTION Hereinafter, although this invention is demonstrated based on an Example, it is not limited to this.

(Sputtering Target Manufacturing Examples 1 to 67)

In ₂ O ₃ powder, SnO ₂ powder, and BaCO ₃ powder of purity> 99.9% were prepared.

First, a total amount of 200 g was prepared at a ratio of 58.6 wt% of BET = 27 m ² / g In ₂ O ₃ powder and 41.4 wt% of BET = 1.3 m ² / g BaCO ³ powder, and mixed with a ball mill in a dry state. , calcined for 3 hours in the atmosphere at 1100 ℃, BaIn ₂ O ₄ to obtain a powder.

Subsequently, Ba and Sn occupy the BaIn ₂ O ₄ powder, BET = 5m ² / g In ₂ O ₃ powder, and BET = 1.5m ² / g SnO ₂ powder with respect to 1 mol of In. About 1.0 kg was prepared by the total amount by the ratio equivalent to mole, and this was mixed with the ball mill. Then, PVA aqueous solution was added as a binder, it mixed, dried, and cold-pressed, and the molded object was obtained. The molded product was degreased at an elevated temperature of 60 ° C./h at 600 ° C. for 10 hours, and then calcined at 1600 ° C. for 8 hours in an oxygen atmosphere to obtain a sintered body. Specifically, the firing conditions are elevated to 100 ° C./h from room temperature to 800 ° C., heated to 400 ° C./h from 800 ° C. to 1600 ° C., and maintained for 8 hours, and then 100 ° C./h from 1600 ° C. to room temperature. It is a condition called cooling on condition. Then, this sintered compact was processed and the target was obtained. At this time, the density and the bulk resistivity are 6.88 g / cm ³ and 2.81 × 10 ⁻⁴ Ω · cm, respectively, in the composition of 32, and 6.96 g / cm ³ and 2.87 × 10 ⁻ , respectively, in the composition of 22, respectively. ^{It was 4} ohm * cm.

(Test Examples A1 to A67)

The sputtering targets of each of Production Examples 1 to 67 were respectively attached to a 4-inch DC magnetron sputtering device, the substrate temperature was set at room temperature (about 20 ° C.), the partial pressure of water was 1.0 × 10 ⁻⁴ Pa, and the oxygen partial pressure was 0 to 3.0. The transparent conductive films of Test Examples A1 to A67 were obtained while changing between sccm (corresponding to 0 to 1.1 × 10 ⁻² Pa).

The sputter | spatter conditions were as follows, and the film | membrane of thickness 1200Å was obtained.

Target dimension: φ = 4in. t = 6mm

Sputter Method: DC Magnetron Sputter

Exhaust System: Rotary Pump + Cryopump

Reach Vacuum Degree: 5.3 × 10 ^-6 [Pa]

Ar pressure: 4.0 × 10 ^-1 [Pa]

Oxygen pressure: 0 to 1.1 x 10 ^-2 [Pa]

Substrate Temperature: Room Temperature

Sputter Power: 130W (Power Density 1.6W / cm ² )

Substrate used: Corning # 1737 (glass for liquid crystal display) t = 0.8mm

In Test Examples A1 to A67, the relationship between the oxygen partial pressure and the resistivity in film formation at room temperature and the oxygen partial pressure and the resistivity after 250 ° C. annealing were determined.

Table 1 and Table 2 show the molar ratios of Ba and Sn, the crystalline state (amorphous film is denoted as a and the crystallized film is denoted as c) in room temperature film formation with respect to 1 mol of In of each sample, and the The crystallization temperature is shown.

In Table 1 and Table 2, the resistivity during film formation means the resistivity of the film at the optimum oxygen partial pressure at room temperature film formation. In addition, the resistivity after annealing was made into the resistivity in the optimum oxygen partial pressure at the time of annealing at 250 degreeC.

In addition, the crystallization temperature shown in Table 1 and Table 2 was calculated | required as follows. After annealing at 250 ° C., the film formed at room temperature at the lowest oxygen partial pressure was annealed at 100 ° C. to 300 ° C. (500 ° C. if necessary) at 50 ° C. for 1 hour in air, and the film was analyzed by thin film XRD. The diffraction line is detected by increasing the annealing temperature with respect to the hollow peak showing the amorphous film formed at room temperature. The initial temperature was determined as the crystallization temperature. In addition, as another calculation method of the crystallization temperature, a high temperature thin film XRD method can also be used.

In addition, Test Examples A1 to A67 were plotted in FIG. 1, where the crystallization temperature was represented by 100 to 300 ° C. and the crystallization temperature was represented by 350 ° C. or more.

As a result, in the range whose crystallization temperature is 300 degrees C or less, (-6.9x10 <^-2> Ln (x) whose molar ratio y of tin with respect to 1 mol of indium is represented by the molar ratio x of barium with respect to 1 mol of indium It turned out that it is below the value of -1.6 * 10 <^-1> and is below the value of (-8.1 * 10 <^-3> Ln (x) + 1.8 * 10 <^-1> ).

(Test Examples B1 to B67)

The sputtering targets of each of Production Examples 1 to 67 were each attached to a 4-inch DC magnetron sputtering device, the substrate temperature was room temperature (about 20 ° C), the partial pressure of water was 1.0 × 10 ^-3 Pa, and the oxygen partial pressure was 0 to 3.0. The transparent conductive film of Test Examples B1-B67 was obtained, changing between sccm (corresponding to 0-1.1 * 10 <^-2> Pa).

The sputter | spatter conditions were as follows, and the film | membrane of thickness 1200Å was obtained.

Target dimension: φ = 4in. t = 6mm

Sputter Method: DC Magnetron Sputter

Exhaust System: Rotary Pump + Cryopump

Reach Vacuum Degree: 5.3 × 10 ^-6 [Pa]

Ar pressure: 4.0 × 10 ^-1 [Pa]

Oxygen pressure: 0 to 1.1 x 10 ^-2 [Pa]

Substrate Temperature: Room Temperature

Sputter Power: 130W (Power Density 1.6W / cm ² )

Substrate used: Corning # 1737 (glass for liquid crystal display) t = 0.8mm

About test Examples B1-B67, the relationship between the oxygen partial pressure and resistivity in film-forming at room temperature, and the relationship between the oxygen partial pressure and resistivity after 250 degreeC annealing were calculated | required.

Table 3 and Table 4 show the molar ratios of Ba and Sn, the crystalline state (denoted amorphous film as a and the crystallized film as c) for room temperature film formation with respect to 1 mol of In of each sample, and amorphous The crystallization temperature of the film is shown. In addition, crystallization temperature, resistivity at the time of film-forming, and resistivity after annealing are as above-mentioned.

Moreover, Test Examples B1-B67 were plotted in FIG. 2, and crystallization temperature showed 100-300 degreeC, and crystallization temperature showed 350 degreeC or more as (circle).

As a result, in the range whose crystallization temperature is 300 degrees C or less, the molar ratio of tin with respect to 1 mol of indium is represented by the molar ratio (x) of barium with respect to 1 mol of indium (-8.1x10 <^-2> Ln (x) -2.6 It turned out that it is below the value of x10 <^-1> and is below the value of (-7.1 * 10 <^-3> Ln (x) + 1.6 * 10 <^-1> ).

(Reference Test Examples C1 to C67)

The sputtering targets of each of Production Examples 1 to 67 were respectively mounted on a 4-inch DC magnetron sputtering device, the substrate temperature was set at room temperature (approximately 20 ° C), and the partial pressure of water was 1.0 x 10 ^-5 Pa. Under the atmosphere, a transparent conductive film of Reference Test Examples C1 to C67 was obtained while varying the oxygen partial pressure between 0 and 3.0 sccm (corresponding to 0 to 1.1 × 10 ⁻² Pa).

The sputter | spatter conditions were as follows, and the film | membrane of thickness 1200Å was obtained.

Target dimension: φ = 4in. t = 6mm

Sputter Method: DC Magnetron Sputter

Exhaust System: Rotary Pump + Cryopump

Reach Vacuum Degree: 5.3 × 10 ^-6 [Pa]

Ar pressure: 4.0 × 10 ^-1 [Pa]

Oxygen pressure: 0 to 1.1 x 10 ^-2 [Pa]

Substrate Temperature: Room Temperature

Sputter Power: 130W (Power Density 1.6W / cm ² )

Substrate used: Corning # 1737 (glass for liquid crystal display) t = 0.8mm

For Reference Test Examples C1 to C67, the relationship between the oxygen partial pressure and the resistivity in film formation at room temperature and the oxygen partial pressure and the resistivity after 250 ° C annealing were determined.

Table 5 and Table 6 below show the molar ratios of Ba and Sn, the crystalline state (amorphous film is indicated as a, and the crystallized film is denoted as c) in room temperature film formation with respect to 1 mol of In of each sample, The crystallization temperature is shown. In addition, crystallization temperature, resistivity at the time of film-forming, and resistivity after annealing are as above-mentioned.

Using the sputtering targets of Production Examples 1 to 67, the relationship between the oxygen partial pressure at room temperature (about 20 ° C.) and the resistivity of the film formed at the partial pressure was obtained to find the optimum oxygen partial pressure, and the film formed at each oxygen partial pressure. From the relationship between the resistivity after annealing the film at 250 ° C. and the deposition oxygen partial pressure, the oxygen partial pressure at which the resistivity after annealing is the lowest is set as the optimum oxygen partial pressure at the time of film formation at 250 ° C., and the optimum oxygen partial pressure is different. It judged whether or not it was, and made different things (circle) and nearly same things into (circle), and was shown in FIG.

As a result, the molar ratio (y) of tin to 1 mol of indium is equal to or more than the value of (-2.9 × 10 ^-2 Ln (x) -6.7 × 10 ^-2 ) represented by the molar ratio (x) of barium to 1 mol of indium. When the film is below the value of (-2.0 × 10 ⁻¹ Ln (x) −4.6 × 10 ⁻¹ ) and is within a range excluding y = 0, the deposition oxygen partial pressure at which the amorphous film after film formation becomes low resistance, It was found that the deposition oxygen partial pressure at which the film after annealing becomes low resistance is different or the optimum oxygen partial pressure at 250 ° C. is different from the optimum oxygen partial pressure at room temperature. That is, in these composition ranges, it is not the optimum oxygen partial pressure determined from the resistivity immediately after film formation, but the film formed at the oxygen partial pressure at which the crystallized film after annealing becomes the lowest resistance becomes lower, and the resistivity of the film after annealing becomes lower, which is more preferable.

The molar ratio y of tin to 1 mole of indium is less than the value of (-2.9 × 10 ⁻² Ln (x) −6.7 × 10 ⁻² ) expressed by the molar ratio x of barium to 1 mole of indium. In the range, it turned out that crystallization temperature is a range smaller than 100 degreeC.

1 and 2, when the film is formed with a partial pressure of water within a predetermined range, the molar ratio y of tin to 1 mol of indium is represented by the molar ratio x of barium to 1 mol of indium ( Even in the range below the value of -2.9 × 10 ⁻² Ln (x) −6.7 × 10 ⁻² ), the crystallization temperature was increased to 150 ° C. or higher, and it was found that the film was easily formed into an amorphous film.

That is, as shown in FIG. 1 and FIG. 2, when the partial pressure of water is formed under the condition of 1.0 × 10 ⁻⁴ Pa or more, less than 1.0 × 10 ⁻⁴ Pa in a state where water is substantially absent as in FIG. 3, preferably It was found that the crystallization temperature of the amorphous resin film was higher than that when the film was formed at a water pressure of 1.0 × 10 ⁻⁵ Pa or less. In particular, under a condition where water is substantially absent, the molar ratio y of tin to 1 mol of indium having a crystallization temperature of less than 100 ° C. is represented by the molar ratio x of barium to 1 mol of indium (−2.9 ×). In the range below the value of 10 ⁻² Ln (x) −6.7 × 10 ⁻² ), even in a range where the crystallization temperature is smaller than 100 ° C., the crystallization temperature is 100 ° C. or higher, preferably 150 ° C. or higher, It turned out that a film | membrane becomes easy to form into a film.

(Test Examples A68 to A74)

In the same manner as in the sputtering target production examples 1 to 67, the targets of the production examples 68 to 74 which consist of the sintered compact of the composition shown in following Table 7 were obtained.

Each target is mounted on a 4-inch DC magnetron sputtering device, and the substrate temperature is room temperature (approximately 20 ° C.), the partial pressure of water is 1.0 × 10 ⁻⁴ Pa, and the oxygen partial pressure is changed between 0 and 3.0 sccm. (Corresponds to 0 to 1.1 × 10 ⁻² Pa) and the transparent conductive films of Test Examples A68 to A74 were obtained.

The sputter | spatter conditions were as follows, and the film | membrane of thickness 1200Å was obtained.

Target dimension: φ = 4in. t = 6mm

Sputter Method: DC Magnetron Sputter

Exhaust System: Rotary Pump + Cryopump

Reach Vacuum Degree: 5.3 × 10 ^-6 [Pa]

Ar pressure: 4.0 × 10 ^-1 [Pa]

Oxygen pressure: 0 to 1.1 x 10 ^-2 [Pa]

Substrate Temperature: Room Temperature

Sputter Power: 130W (Power Density 1.6W / cm ² )

Substrate used: Corning # 1737 (glass for liquid crystal display) t = 0.8mm

About test Examples A68-A74, the relationship between oxygen partial pressure and resistivity in film-forming at room temperature, and the relationship between oxygen partial pressure and resistivity after 250 degreeC annealing were calculated | required.

Table 7 shows the molar ratios of Ba and Sn, the crystalline state (amorphous film is denoted as a and the crystallized film is denoted as c) in room temperature film formation, and the crystallization temperature of the amorphous film with respect to 1 mol of In of each sample. Indicated. In addition, crystallization temperature, resistivity at the time of film-forming, and resistivity after annealing are as above-mentioned.

Test Examples A68 to A74 were also plotted in Fig. 1 together with Test Examples A1 to A18, where the crystallization temperature was 100 to 300 ° C and the crystallization temperature was 350 ° C or higher.

(Test Examples B68 to B74)

The targets of Production Examples 68 to 74 were each attached to a 4-inch DC magnetron sputtering device, the substrate temperature was room temperature (about 20 ° C), the partial pressure of water was 1.0 × 10 ^-3 Pa, and the oxygen partial pressure was 0 to 3.0 sccm. While changing among (corresponding to 0-1.1 * 10 <^-2> Pa), the transparent conductive film of Test Examples B68-B74 was obtained.

The conditions of sputter | spatter were the same as Test Examples A68-A74, and the film | membrane of thickness 1200Å was obtained.

About test Examples B68-B74, the relationship between oxygen partial pressure and resistivity in film-forming at room temperature, and the relationship between oxygen partial pressure and resistivity after 250 degreeC annealing were calculated | required.

Table 8 shows the molar ratios of Ba and Sn, the crystalline state (amorphous film is designated as a and the crystallized film is denoted as c) in room temperature film formation, and the crystallization temperature of the amorphous film with respect to 1 mol of In of each sample. Indicated. In addition, crystallization temperature, resistivity at the time of film-forming, and resistivity after annealing are as above-mentioned.

Test Examples B68 to B74 were also plotted in FIG. 2 together with Reference Test Examples B1 to B67, where crystallization temperatures of 100 to 300 ° C and crystallization temperatures of 350 ° C or more were indicated as ■ and less than 100 ° C.

(Reference Test Examples C68 to C74)

The target of manufacture examples 68-74 was attached to the 4-inch DC magnetron sputter apparatus, respectively, board | substrate temperature is room temperature (about 20 degreeC), partial pressure of water is 1.0 * 10 <^-5> Pa, and there is no atmosphere substantially in an atmosphere. The transparent conductive films of Reference Test Examples C68 to C74 were obtained while changing the partial pressure of oxygen under 0 to 3.0 sccm (corresponding to 0 to 1.1 × 10 ⁻² Pa).

The conditions of sputter | spatter were the same as Test Examples A68-A74, and the film | membrane of thickness 1200Å was obtained.

For Reference Test Examples C68 to C74, the relationship between the oxygen partial pressure and the resistivity in film formation at room temperature and the oxygen partial pressure and the resistivity after 250 ° C. annealing were determined.

In Table 9 below, the molar ratio of Ba and Sn, the crystal state (amorphous film is denoted as a and the crystallized film is denoted as c) in room temperature film formation with respect to 1 mol of In of each sample, and the crystallization temperature of the amorphous film is shown. Indicated. In addition, crystallization temperature, resistivity at the time of film-forming, and resistivity after annealing are as above-mentioned.

The results of Test Examples C68 to C74 were also plotted in FIG. 3 together with Reference Test Examples C1 to C67. That is, for the targets of Production Examples 68 to 74, the relationship between the oxygen partial pressure at room temperature (about 20 ° C.) and the resistivity of the film formed at the partial pressure was obtained to find the optimum oxygen partial pressure, and the films formed at each oxygen partial pressure were obtained. From the relationship between the resistivity after annealing at 250 ° C. and the deposition oxygen partial pressure, the oxygen partial pressure at which the resistivity after annealing is the lowest is set as the optimum oxygen content when forming at 250 ° C., and the optimum oxygen partial pressure is different. It judged whether it was or not, and made different things (circle) and nearly same things into (circle), and was shown in FIG.

(Existence confirmation test of hydrogen)

The sputtering target of Preparation Example 13 was attached to a 4-inch DC magnetron sputtering device, respectively, and the substrate temperature was room temperature (about 20 ° C.), the partial pressure of water was 1.0 × 10 ⁻² Pa (as Example 1), 5.0 × 10 ^{−. 3} Pa (referred to as example 2) and 5.0 × 10 ^-5 Pa conducted in three conditions (comparative examples referred to as 1) example 1, example 2 and Comparative example 1 of the transparent conductive film was obtained.

The sputter | spatter conditions were as follows, and the film | membrane of thickness 1200Å was obtained.

Target dimension: φ = 4in. t = 6mm

Sputter Method: DC Magnetron Sputter

Exhaust System: Rotary Pump + Cryopump

Reach Vacuum Degree: 5.3 × 10 ^-5 [Pa]

Ar pressure: 4.0 × 10 ^-1 [Pa]

Oxygen pressure: 0 [Pa]

Substrate Temperature: Room Temperature

Sputter Power: 130W (Power Density 1.6W / cm ² )

Substrate used: Corning # 1737 (glass for liquid crystal display) t = 0.8mm

Here, when the crystal state of the sample formed under each condition was analyzed by thin film XRD, it was confirmed that it is amorphous in Example 1 and Example 2, and crystallized in Comparative Example 1.

In addition, about presence of hydrogen in each film | membrane, the measurement shown below about the sample of Example 1 and the comparative example 1 using time-of-flight type secondary ion mass spectrometry (TOF-SIMS, TRIFT IV by ULVAC PHI) The conditions were confirmed by comparing (H ⁺ ionized water) / (total ionized water) detected.

[Measuring conditions]

Primary ion: Au ⁺

Acceleration voltage: 30 kV

Scanning Conditions: Raster Scan (200 × 200 μm)

Table 10 shows (count of H ⁺ ions) / (count of all ions) which is a result of TOF-SIMS analysis of the sample formed into a film.

Here, the H ⁺ ions are also detected in the sample of Comparative Example 1 formed in an atmosphere in which the water pressure at the time of film formation is 5.0 × 10 ⁻⁵ and substantially no water is present, but this can be judged as the background. That is, in a recent study, it was reported that H ⁺ ions were detected from an indium oxide film formed at a partial pressure lower than that of Comparative Example 1 (Jpn. J. Appl. Phys., Vol. 46, No. 28). , 2007, pp. L685-L687), it can be inferred that the detected hydrogen ions contained in the film a slight moisture adhering to the substrate at the time of film formation. Therefore, in the present invention, the reference value is set to 7.75 × 10 ^−4, which is (H ⁺ ionized water) / (total ionized water) of a sample formed by forming a water pressure under an atmosphere in which water is substantially free of 5.0 × 10 ⁻⁵ or less. Then, the increased (H ⁺ ionized water) / (total ionized water) than this is taken as the hydrogen ions contained in the membrane.

Therefore, when Examples 1 and 2 and Comparative Example 2 (counts of H ⁺ ions) / (counts of all ions) are compared, it can be seen that the moisture pressure at the time of film formation increases as the water pressure increases. Therefore, as in Examples 1 and 2, it was confirmed that by controlling the water pressure during film formation, the amount of hydrogen due to water intake in the film can be changed. In addition, it is estimated that hydrogen received in the film has an effect of inhibiting crystallization of the film by hydrogen termination with dangling bonds (unbonded hands) of atoms in the film.

Claims (14)

A transparent conductive film formed as a film of amorphous by using a sputtering target containing an oxide sintered body containing indium oxide and tin and containing barium in an amount of 0.00001 mol or more and less than 0.10 mol with respect to 1 mol of indium. A transparent conductive film containing tin, containing barium, and formed under the condition that the partial pressure of water is 1.0 × 10 ⁻⁴ Pa or more and 1.0 × 10 ⁻¹ Pa or less. A transparent conductive film as set forth in claim 1, wherein said amorphous film contains hydrogen. The molar ratio y of tin to 1 mol of indium is represented by the molar ratio x of barium to 1 mol of indium (-6.9 x 10 ^-2 Ln (x) -1.6 x). 10 value of less than ¹⁾ and also ^{(-8.1 × 10 -3 Ln (x} ) + 1.8 × 10 -1) a transparent conductive film, characterized in that in the scope of the following values: The molar ratio y of tin to 1 mol of indium is represented by the molar ratio x of barium to 1 mol of indium (-8.1 x 10 ^-2 Ln (x) -2.6 x). 10 value of less than ¹⁾ and also ^{(-7.1 × 10 -3 Ln (x} ) + 1.6 × 10 -1) a transparent conductive film, characterized in that in the scope of the following values: The transparent conductive film according to claim 4, wherein the partial pressure of water is formed under a condition of 1.0 × 10 ⁻³ Pa or more and 1.0 × 10 ⁻¹ Pa or less. The transparent conductive film according to any one of claims 1 to 5, wherein the transparent conductive film is a film which is crystallized by annealing after film formation. The transparent conductive film according to claim 6, wherein the annealing is performed at 100 to 300 ° C. The resistivity of the transparent conductive film after annealing is 5.0x10 <^{-4> (} ohm) * cm or less, The transparent conductive film of Claim 6 or 7 characterized by the above-mentioned. A sputtering target containing an indium oxide and tin and an oxide sintered body containing 0.00001 mol or more and less than 0.10 mol with respect to 1 mol of indium, using indium oxide and tin, and also containing barium When forming an amorphous film, the partial pressure of water at the time of film formation is 1.0 * 10 <^-4> Pa or more and 1.0 * 10 <^-1> Pa or less, The manufacturing method of the transparent conductive film characterized by the above-mentioned. 10. The molar ratio y of tin to 1 mole of indium is represented by the molar ratio x of barium to 1 mole of indium (-6.9 × 10 ⁻² Ln (x) −1.6 × 10 ⁻¹ ) The film is formed using a sputtering target that is equal to or less than the value of and is in the range equal to or less than the value of (−8.1 × 10 ⁻³ Ln (x) + 1.8 × 10 ⁻¹ ). 10. The molar ratio y of tin to 1 mole of indium is represented by the molar ratio x of barium to 1 mole of indium (−8.1 × 10 ⁻² Ln (x) −2.6 × 10 ⁻¹ ) Using a sputtering target that is equal to or less than and equal to (-7.1 × 10 ^-3 Ln (x) + 1.6 × 10 ⁻¹ ), the partial pressure of water during film formation is 1.0 × 10 ⁻³ or more and 1.0 ×. The film formation is carried out at 10 ^-1 Pa or less, The manufacturing method of the transparent conductive film characterized by the above-mentioned. The method for producing a transparent conductive film according to any one of claims 9 to 11, wherein the film of amorphous film is crystallized by annealing after film formation. The method for producing a transparent conductive film according to claim 12, wherein the crystallization by annealing is performed at 100 to 300 deg. The method for producing a transparent conductive film according to claim 13, wherein the resistivity of the transparent conductive film after annealing is 5.0 × 10 ⁻⁴ Ω · cm or less.

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