JP3781398B2 - I. T.A. O sintered body, production method thereof, and I.I. T.A. O thin film - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to I.D. for vacuum film formation for forming a transparent conductive film. T. T. et al. O sintered body and production method thereof, and I.I. T. T. et al. This relates to an O thin film.
[0002]
[Prior art]
I. Indium oxide (In ₂ O ₃ ) and tin oxide (SnO ₂ ) T. T. et al. O sintered compact is used as a transparent conductive film such as a transparent electrode, antistatic, electromagnetic wave blocking, surface heating element, heat ray blocking, photoelectric conversion element, etc. Widely used.
[0003]
Among them, I.I., which is used as a transparent electrode, by increasing the size of LCD (liquid crystal display), high definition, and high image quality. T. T. et al. The characteristic requirements for O films are becoming stricter. In particular, lowering resistance is a major issue.
[0004]
In the vacuum film formation method, T. T. et al. The following reports have been made as a method for obtaining a high-quality transparent conductive film from an O sintered body.
First, JP-A-3-126655 discloses an average particle size of 0. A method is disclosed in which a binder is added to indium oxide-tin oxide powder of 1 μm or less and mixed and then sintered in an oxygen atmosphere at 1500 ° C. or higher.
Japanese Patent Application Laid-Open No. 3-150253 discloses a method of once sintering in an oxygen atmosphere of 1200 ° C. to 1300 ° C. and then heat-treating in a reduced pressure of 500 to 1300 ° C. or an inert gas atmosphere.
[0005]
In JP-A-6-316760, tin oxide-indium oxide powder is calcined in the air, and the calcined powder is mixed, granulated, and molded, and sintered at a sintering temperature of 900 ° C. to 1100 ° C. A method is disclosed.
“Functional Materials” Vol. 11, no. 3 (1991) having a density of 63%. T. T. et al. O target I.I. T. T. et al. The specific resistance of the O film is due to the large difference in the amount of SnO ₂ in the film due to the sputtering power. It is very important to use a target that takes into account the optimum amount of SnO ₂ for the sputtering equipment and conditions used. It is described that there is.
[0006]
Furthermore, “New Glass” Vol. 7, no. 2 (1992), I.V. T. T. et al. It is described that the optimum amount of SnO ₂ added to the O pellet shows the closest specific resistance to the added amount of around 5 wt%.
[0007]
[Problems to be solved by the invention]
As described above, I.I. T. T. et al. In order to obtain a high-quality transparent conductive film from the O sintered body, the vacuum deposition I.V. T. T. et al. O pellet or sputtering I. T. T. et al. It is necessary to optimize the density of the O target and the precise SnO ₂ content and to precisely control the conditions of the vacuum deposition apparatus, and to produce a transparent conductive I.D. T. T. et al. It is difficult to obtain an O thin film.
[0008]
The present invention has been made to solve such problems of the prior art, and is affected by variations in SnO _{2 in} the sintered body (difference in the amount of SnO ₂ in the ITO thin film). I. It is difficult to achieve, I.I. T. T. et al. O sintered body and transparent conductive material T. T. et al. The object is to provide an O thin film.
[0009]
Furthermore, the present invention provides a transparent conductive I.D. T. T. et al. Since an O thin film can be provided, the film thickness can be increased within a range not losing the transmittance (80% or more) as a transparent conductive film, and the resistance of the entire film can be reduced. T. T. et al. The object is to provide an O thin film.
[0010]
[Means for Solving the Problems]
That is, the present invention contains indium oxide (In ₂ O ₃ ), tin oxide (SnO ₂ ) and scandium oxide (Sc ₂ O ₃ ) as main components, and the ratio of the indium oxide, scandium oxide and tin oxide. Is in weight ratio (In ₂ O ₃ + Sc ₂ O ₃ ): SnO ₂ = 99 to 93: 1 to 7, and the content of scandium oxide is in weight ratio with indium oxide, In ₂ O ₃ : Sc ₂ O ₃ = 99.8-60: 0.2-40. T. T. et al. This relates to the O sintered body.
[0011]
Further, the present invention contains indium oxide (In ₂ O ₃ ), tin oxide (SnO ₂ ) and scandium oxide (Sc ₂ O ₃ ) as main components, and the ratio of the indium oxide, scandium oxide and tin oxide is weight. (In ₂ O ₃ + Sc ₂ O ₃ ): SnO ₂ = 99 to 93: 1 to 7 and the content of scandium oxide by weight ratio to indium oxide is In ₂ O ₃ : Sc ₂ O ₃ = 99.8-60: 0.2-40 powder is mixed, molded, heated and sintered. T. T. et al. It is a manufacturing method of O sintered compact.
[0013]
Furthermore, the present invention provides the above-mentioned I.I. T. T. et al. It is formed by forming a film using an O sintered body as a vapor deposition source. T. T. et al. O thin film.
It is preferable that the same volume resistivity is obtained regardless of the difference in the content of tin (Sn) in the thin film.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
In order to achieve the above object, the present invention provides an I.V. comprising In ₂ O ₃ and SnO ₂ as main components. T. T. et al. It is characterized by adding Sc ₂ O ₃ to O powder.
[0015]
The ratio of In ₂ O ₃ and Sc ₂ O ₃ to SnO ₂ is (In ₂ O ₃ + Sc ₂ O ₃ ): SnO ₂ = 99 to 94: 1 to 7, more preferably 98 to 94: 2 It is desirable to be ~ 6. By making the ratio of the above In ₂ O ₃ , Sc ₂ O ₃ and SnO ₂ , no splash is generated by vacuum film formation, and the transmittance is 91% or more, and the volume resistivity is 3.3 × 10 ⁻⁴ Ω · Operates to indicate cm or less.
[0016]
Also, Sc ₂ O ₃ content is In ₂ O ₃ and the weight ratio _{In 2 O 3: Sc 2 O} 3 = 99.8~60: 0.2~40, preferably 99.7 to 62: 0 .3 to 38 is desirable. By setting the ratio of In ₂ O ₃ and Sc ₂ O ₃ as described above, no splash is generated by vacuum film formation, and the transmittance is 91% or more and the volume resistivity is 7 × 10 ⁻⁴ Ω · cm or less. Operate.
[0017]
I. of the present invention. T. T. et al. The method for producing the O sintered body is performed by mixing, forming, heating and sintering powders of In ₂ O ₃ , SnO ₂ and Sc ₂ O ₃ as main components.
The method of molding and heat sintering is not particularly limited, and can be performed by a normal method. For example, a uniaxial pressure molding method is used as a molding method, and heating and firing is performed in the atmosphere as a heat sintering method. Things can be mentioned.
[0018]
I. of the present invention. T. T. et al. The O thin film has the above-mentioned I.V. T. T. et al. It is obtained by depositing an O sintered body to form a film. The film forming method is not particularly limited and can be performed by a normal method.
I. T. T. et al. In the thin film formed by vapor-depositing the O sintered body, Sc is uniformly dispersed between the surface of the thin film and the substrate, and the same amount is contained.
In addition, I.I. T. T. et al. A thin film formed by vapor-depositing an O sintered body has the same volume resistivity regardless of the difference in Sn content in the thin film. I. for LCD T. T. et al. The volume resistivity of the O thin film is preferably the same value in the range of 1.0 × 10 ^{−4 to} 3.5 × 10 ⁻⁴ Ω · cm.
[0019]
【Example】
Hereinafter, the present invention will be described using examples.
[0020]
Example 1
The ratio of In ₂ O ₃ and Sc ₂ O ₃ to SnO ₂ is (In ₂ O ₃ + Sc ₂ O ₃ ): SnO ₂ = 99 to 94: l to 7 (SnO ₂ 1 to 7%) in weight ratio. To. Preferably 2-6% of SnO ₂ is added. In this example, 2% of SnO ₂ was added.
[0021]
Next, In ₂ O ₃ and Sc ₂ O ₃ (purity 99.9%, impurity analysis result (ppm) by ICP emission analysis: Ca 25, Y 180, Dy 52, Ho 30, Er 30, Tm 15, Yb 90, Lu 25) is added so that the weight ratio is In ₂ O ₃ : Sc ₂ O ₃ = 99.5: 0.5. This mixture is mixed using a ball mill while forming a sufficiently fine granular shape.
[0022]
Thereafter, it is formed into a pellet shape having a size of 17 square mm × 20 ^t mm at a press pressure of 1300 kgf / cm ² . After pressing, heat in the atmosphere at 1350 ° C. T. T. et al. An O sintered body is obtained.
[0023]
In the electron beam evaporation source part of a normal vacuum deposition apparatus, this I.D. T. T. et al. O sintered a sintered body was placed the oxygen gas pressure 5 × l0 ^-4 torr, I. a thickness 1200Å in deposition rate 3.0 Å / sec in the synthetic quartz substrate in an atmosphere of a substrate temperature of 300 ° C. T. T. et al. An O film was produced. The obtained I.V. T. T. et al. The transmittance of the O film was 95% at a wavelength of 550 nm, and the volume resistivity measured by the four probe method was 3.2 × 10 ⁻⁴ Ω · cm.
[0024]
Further, in secondary ion mass spectrometry (hereinafter abbreviated as SIMS analysis), I.V. T. T. et al. When the dispersion state of Sn and Sc in the O film was measured, the intensity of ¹²⁰ Sn ⁺ was 2 × 10 ³ (counts) and the intensity of ⁴⁵ Sc ⁺ was 2 × 10 ⁴ (counts). It was confirmed that they were dispersed.
[0025]
Example 2
As in Example 1, except that the SnO ₂ content is 6%, I.V. T. T. et al. An O sintered body was produced and evaporated.
The transmittance of the obtained thin film at a wavelength of 550 nm was 96%, and the volume resistivity was 3.0 × 10 ⁻⁴ Ω · cm. I.S by SIMS analysis. T. T. et al. When the dispersion state of Sn and Sc in the O film was measured, the intensity of ¹²⁰ Sn ⁺ was 4.5 × 10 ³ (counts), and the intensity of ⁴⁵ Sc ⁺ was 2 × 10 ⁴ (counts). It was confirmed that they were uniformly dispersed.
[0026]
Furthermore, I.S. T. T. et al. When ¹¹³ In ⁺ in the O film was measured, the strength of both Examples 1 and 2 was 1.2 × 10 ⁵ (counts).
According to SIMS analysis from Examples 1 and 2, I.V. T. T. et al. If the same amount of Sc is contained in the O film, even if there is a difference of about three times as much as the Sn content, I.V. T. T. et al. It can be seen that an O thin film can be obtained.
[0027]
In addition, when the component of SnO ₂ is in the range of 1 to 7% and the content of Sc ₂ O ₃ is 0.2 to 1.5% by weight ratio to In ₂ O ₃ , the wavelength is 550 nm. The transmittance was 91% or more, and the volume resistivity was in the range of 2.7 to 3.3 × 10 ⁻⁴ Ω · cm. In SIMS analysis, the same results as in this example were obtained.
[0028]
Comparative Example 1
As in Example 1, except that the SnO ₂ content is 0.5%, which is less than 1%, I.I. T. T. et al. An O sintered body was produced and evaporated.
The transmittance of the obtained thin film at a wavelength of 550 nm was 82%, and the volume resistivity was 3.5 × 10 ⁻⁴ Ω · cm.
[0029]
Comparative Example 2
As in Example 1, except that the SnO ₂ content is more than 7% and 10%, I.V. T. T. et al. An O sintered body was produced and evaporated.
The transmittance of the obtained thin film at a wavelength of 550 nm was 54%.
[0030]
Example 3
The ratio of In ₂ O ₃ and Sc ₂ O ₃ to SnO ₂ is set to (In ₂ O ₃ + Sc ₂ O ₃ ): SnO ₂ = 95: 5 by weight. Then In ₂ O ₃ and Sc ₂ an In at a ratio of O ₃ weight ratio _{2 O 3: Sc 2 O 3} = 99.8~60.0: 0.2~40 (Sc 2 O 3 0.2~40% ) To add each. Preferably, Sc ₂ O ₃ is added in an amount of 0.3 to 38%. In this example, 5% of Sc ₂ O ₃ was added. This mixture is mixed using a ball mill while forming a sufficiently fine granular shape.
[0031]
Thereafter, it is molded into a pellet shape having a size of 17 square mm × 20 ^t mm at a press pressure of 1300 kgf / cm ² . After pressing, it is heated at a temperature of 1350 ° C. in the atmosphere. T. T. et al. An O sintered body is obtained.
[0032]
Next, vapor deposition was performed in the same manner as in Example 1.
The transmittance of the obtained thin film at a wavelength of 550 nm was 94%, and the volume resistivity was 3.8 × 10 ⁻⁴ Ω · cm.
[0033]
Example 4
As in Example 3 , except that the component of Sc ₂ O ₃ is 35.0%. T. T. et al. An O sintered body was produced and evaporated.
The transmittance of the obtained thin film at a wavelength of 550 nm was 92%, and the volume resistivity was 6.2 × 10 ⁻⁴ Ω · cm.
[0034]
When the Sc ₂ O ₃ component is in the range of 0.2 to 40%, the transmittance of the obtained thin film at a wavelength of 550 nm is 91% or more, and the volume resistivity is 2.7 to 7.0 × 10. ^It was confirmed that it was in the range of ⁻⁴ Ω · cm.
[0035]
Comparative Example 3
As in Example 3 , except that the Sc ₂ O ₃ content is 0.1%, which is less than 0.2%. T. T. et al. An O sintered body was produced and evaporated.
The transmittance of the obtained thin film at a wavelength of 550 nm was 84%, and the volume resistivity was 9.7 × 10 ⁻⁴ Ω · cm.
[0036]
Comparative Example 4
Except that components of sc ₂ O ₃ is 50% in excess of 40%, as in Example 3 I. T. T. et al. An O sintered body was produced and evaporated.
The transmittance of the obtained thin film at a wavelength of 550 nm was 94%, and the volume resistivity was 7.8 × 10 ⁻³ Ω · m.
[0037]
【The invention's effect】
As described above, according to the present invention, I.I. T. T. et al. Transparent conductive I.O. is less affected by variations in SnO ₂ in the O sintered body (difference in the amount of SnO ₂ in the ITO thin film), has high transmittance, and has a reproducible and stable specific resistance. T. T. et al. An O thin film can be produced, which is very useful for enlargement of LCDs, high definition, and high image quality.

Claims (4)

It contains indium oxide (In ₂ O ₃ ), tin oxide (SnO ₂ ), and scandium oxide (Sc ₂ O ₃ ) as main components, and the ratio of the indium oxide, scandium oxide, and tin oxide is (In ₂ O ₃ + Sc ₂ O ₃ ): SnO ₂ = 99 to 93: 1 to 7 and the content of scandium oxide is In ₂ O ₃ : Sc ₂ O ₃ = 99.8 to the weight ratio of indium oxide. 60: 0.2-40. T. T. et al. O sintered body. Indium oxide (In ₂ O ₃ ), tin oxide (SnO ₂ ), and scandium oxide (Sc ₂ O ₃ ) are contained as main components, and the ratio of the indium oxide, scandium oxide, and tin oxide is (In ₂ O _{3 + Sc 2 O 3):} SnO 2 = 99~93: a 1-7, and _in 2 _O in a weight ratio between the content of scandium oxide indium oxide _{3: Sc 2 O 3 = 99.8~60} : 0.2 to 40 powders are mixed, molded, heated and sintered. T. T. et al. Manufacturing method of O sintered compact. The I.D. of claim 1. T. T. et al. It is formed by forming a film using an O sintered body as a vapor deposition source. T. T. et al. O thin film. The I.D. of claim 3 wherein the same volume resistivity is obtained regardless of the difference in the content of tin (Sn) in the thin film. T. T. et al. O thin film.