JPWO2013172354A1 - Conductive film material, conductive film laminate, electronic device, and conductive film material and method of manufacturing conductive film laminate - Google Patents

Abstract

Provided is a conductive film material having an amorphous layer that is easy to crystallize by heat treatment, has a low sheet resistance when crystallized, and suppresses an increase in film thickness. The conductive film material has a transparent base material and an amorphous layer made of indium tin oxide laminated on the transparent base material. The amorphous layer is made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide, the film thickness is 15 to 25 nm, and the sheet resistance value when crystallized is 50 to 150Ω. / □.

Description

  The present invention relates to a conductive film material, a conductive film laminate, an electronic device, and a conductive film material and a method of manufacturing the conductive film laminate.

  Since the transparent conductive film has conductivity and optical transparency, it is used as a transparent electrode, an electromagnetic wave shielding film, a planar heating film, an antireflection film, and the like, and has recently attracted attention as a touch panel electrode. There are various types of touch panels such as a resistive film type, a capacitive coupling type, and an optical type. The transparent conductive film is used in, for example, a resistance film type that identifies a touch position by contacting upper and lower electrodes, and a capacitive coupling method that senses a change in capacitance. The transparent conductive film used for the resistance film type is required to have high durability because the transparent conductive films are in mechanical contact with each other on the principle of operation. In addition, the transparent conductive film used in the capacitive coupling method and some resistive film types has good etching properties because a large number of transparent electrodes are formed by etching so as to have a specific pattern. Desired. Moreover, since a transparent conductive film is arrange | positioned in the front surface of a display part, a high light transmittance is calculated | required.

  Examples of the transparent conductive film include those made of indium tin oxide. The durability of the indium tin oxide can be improved by crystallization. However, indium tin oxide to be a transparent conductive film may form a large number of transparent electrodes by etching, and if crystallized, it becomes difficult to form a large number of transparent electrodes by etching. For example, when indium tin oxide is crystallized, it takes time to form the transparent electrode because the etching rate decreases, and the shape of the transparent electrode may not be a desired shape.

  From this point of view, after forming an indium tin oxide in an amorphous state that is easy to etch and etching the indium tin oxide in the amorphous state to form a large number of transparent electrodes It is preferable to crystallize by heat treatment. In this case, the amorphous indium tin oxide is required to be easily crystallized by heat treatment. In addition, the specific resistance when crystallized is also required to be low. When the specific resistance is low, the sheet resistance value can be reduced even if the film thickness is reduced. In addition, the transparent conductive film is required to have high transmittance, but the transmittance can be increased by reducing the film thickness. Conventionally, indium tin oxide containing about 3% by mass of tin in terms of oxide is used because crystallization by heat treatment is easy and the specific resistance when crystallized is relatively low (for example, Patent Literatures 1 to 3).

Japanese Unexamined Patent Publication No. 2011-65937 Japanese Unexamined Patent Publication No. 2011-1000074 Japanese Unexamined Patent Publication No. 2004-14984

  In recent years, with the increase in size of electronic devices such as touch panel devices, there is a concern about a decrease in transmission speed in a transparent conductive film during operation. In order to suppress a decrease in transmission speed, it is required to further reduce the sheet resistance value of the transparent conductive film. Specifically, it is required to reduce the sheet resistance value of the transparent conductive film to 150Ω / □ or less.

  For indium tin oxide containing about 3% by mass of tin described above in terms of oxide, the sheet resistance value when crystallized can be reduced by increasing the film thickness, but to have a predetermined sheet resistance value. Therefore, it is necessary to make the film thickness sufficiently thick. The film thickness is preferably 25 nm or less from the viewpoint of improving the optical characteristics such as transmittance, but indium tin oxide containing about 3% by mass of tin described above in terms of oxide is to obtain a predetermined sheet resistance value. It is necessary to make the film thickness more than 25 nm.

  On the other hand, indium tin oxide containing about 10% by mass of tin in terms of oxide is also known as a constituent material of the transparent conductive film. From indium tin oxide containing about 3% by mass of tin described above in terms of oxide Can also reduce the sheet resistance when crystallized. However, indium tin oxide containing about 10% by mass of tin in terms of oxide is not always easily crystallized, and optical properties such as transmittance are not good when the thickness is required for crystallization.

  The present invention has been made to solve the above-described problems, and is an amorphous material that is easy to crystallize by heat treatment, has a low sheet resistance when crystallized, and suppresses an increase in film thickness. An object is to provide a conductive film material having a layer. Another object of the present invention is to provide a conductive film stack having a crystalline layer with a low sheet resistance value and a suppressed increase in film thickness, and an electronic device having the conductive film stack. Furthermore, this invention aims at provision of the manufacturing method of the above-mentioned raw material for electrically conductive films, and an electrically conductive film laminated body.

  The conductive film material of the present invention has a transparent base material and an amorphous layer made of indium tin oxide laminated on the transparent base material. The amorphous layer is made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide, the film thickness is 15 to 25 nm, and the sheet resistance value when crystallized is 50 to 150Ω. / □.

  The electrically conductive film laminated body of this invention has a transparent base material and the crystalline layer which consists of an indium tin oxide laminated | stacked on the said transparent base material. The crystalline layer is made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide, has a film thickness of 15 to 25 nm, and a sheet resistance value of 50 to 150Ω / □.

  The electronic device of the present invention has the above-described conductive film laminate of the present invention.

  In the method for producing a conductive film material of the present invention, the film thickness is measured by a sputtering method using a sputtering target made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide on a transparent substrate. It has a film forming step of forming an amorphous layer having a sheet resistance value of 50 to 150 Ω / □ when crystallized at 15 to 25 nm.

In the method for producing a conductive film laminate of the present invention, the film thickness is measured by a sputtering method using a sputtering target made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide on a transparent substrate. A film forming step for obtaining a conductive film material by forming an amorphous layer having a sheet resistance of 50 to 150 Ω / □ when crystallized at 15 to 25 nm, and heat-treating the conductive film material And a heat treatment step of crystallizing the amorphous layer to form a crystalline layer.
In the method for producing a conductive film laminate of the present invention, the film thickness is measured by a sputtering method using a sputtering target made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide on a transparent substrate. A film forming step of obtaining a conductive film material by forming an amorphous layer having a sheet resistance of 50 to 150 Ω / □ when crystallized at 15 to 25 nm, and an amorphous state of the conductive film material It is characterized by comprising a step of patterning the material layer by etching and a heat treatment step of heat-treating the patterned conductive film material to crystallize the amorphous layer to form a crystalline layer.

  According to the present invention, it is possible to provide a conductive film material having an amorphous layer that is easy to crystallize by heat treatment, has a low sheet resistance when crystallized, and suppresses an increase in film thickness. In addition, according to the present invention, it is possible to provide a conductive film stack having a crystalline layer having a low sheet resistance value and a suppressed increase in film thickness, and an electronic device having the conductive film stack. Furthermore, according to the present invention, a manufacturing method for manufacturing the above-described conductive film material and conductive film laminate can be provided.

Sectional drawing which shows one Embodiment of the raw material for electrically conductive films. Sectional drawing which shows one Embodiment of an electrically conductive film laminated body. The figure which shows an example of the relationship between the oxygen gas flow rate at the time of film-forming of an amorphous layer, and the sheet resistance value before and behind heat processing of an amorphous layer. The figure which shows an example of the relationship between the content in the oxide conversion of tin in a sputtering target, and oxygen gas flow volume (optimal flow volume) when sheet resistance value becomes the minimum value.

Hereinafter, the present invention will be described in detail.
FIG. 1 is a cross-sectional view showing an embodiment of a conductive film material.

  The conductive film material 10 includes, for example, a transparent substrate 11 and an amorphous layer 12 made of indium tin oxide in an amorphous state laminated on the transparent substrate 11. Such a conductive film material 10 is used for manufacturing a conductive film laminate in which a crystalline transparent conductive film made of crystalline indium tin oxide is stacked on a transparent substrate 11. That is, the amorphous layer 12 is crystallized by heat treatment to become a crystalline transparent conductive film.

  Here, amorphous and crystalline means the rate of change in resistance value obtained by measuring the resistance value before and after being immersed in an HCl solution (concentration 1.5 mol / L) for 3 minutes (resistance value after immersion / before immersion). Resistance value). When this resistance value change rate exceeds 200%, it is evaluated as amorphous, and when the resistance value change rate is 200% or less, it is evaluated as crystalline.

  The transparent substrate 11 is, for example, polyolefin such as polyethylene or polypropylene, polyester such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyamide such as nylon 6, nylon 66, polyimide, polyarylate, polycarbonate, polyacrylate, polyether. Sulphone, polysulfone, and unstretched or stretched plastic films of these copolymers are preferred. In addition, the transparent base material 11 can also use another highly transparent plastic film. Among these, a plastic film made of polyethylene terephthalate is particularly preferable.

  A primer layer such as a hard coat layer may be formed on one or both surfaces of the transparent substrate 11. Further, the transparent substrate 11 may be subjected to surface treatment such as easy adhesion treatment, plasma treatment, corona treatment and the like. The thickness of the transparent substrate 11 is preferably 10 to 200 μm from the viewpoint of flexibility and durability.

  Examples of the hard coat layer include a transparent and hard organic material layer. 1-15 micrometers is preferable and, as for the thickness of a hard-coat layer, 1.5-10 micrometers is more preferable. By setting the film thickness of the hard coat layer to 1 μm or more, it is possible to obtain the expected effect due to the formation of the hard coat layer. Moreover, by making a film thickness 15 micrometers or less, while being able to suppress the fall of film forming efficiency, generation | occurrence | production of a crack can also be suppressed.

  The hard coat layer is made of, for example, a curable resin or a thermosetting resin that is cured by ionizing radiation. The curable resin material that is cured by ionizing radiation may include an acrylic material, a polyfunctional or polyfunctional (meth) acrylate compound such as an acrylic acid or a methacrylic acid ester of a polyhydric alcohol, a diisocyanate and a polyhydric alcohol, and A polyfunctional urethane (meth) acrylate compound synthesized from a hydroxyester of acrylic acid or methacrylic acid can be used. Besides these, polyether resins having an acrylate functional group, polyester resins, epoxy resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, and the like can be used. A thermosetting polysiloxane resin or the like can also be used.

  As a coating method of the curable resin, a wet film forming method is preferable, and a coating method using a roll coater, a reverse roll coater, a gravure coater, a micro gravure coater, a knife coater, a bar coater, a wire bar coater, a die coater, and a dip coater. Is preferred.

  As ionizing radiation, for example, ultraviolet rays and electron beams can be used. In the case of ultraviolet curing, a light source such as a high pressure mercury lamp, a low pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a carbon arc, or a xenon arc can be used. In the case of electron beam curing, electron beams emitted from various electron beam accelerators such as cockloftwald type, bandegraph type, resonant transformer type, insulated core transformer type, linear type, dynamitron type, and high frequency type can be used. .

  A base layer (not shown) may be provided between the transparent substrate 11 and the amorphous layer 12 in order to promote crystallization during the heat treatment of the amorphous layer 12. The underlayer is not particularly limited as long as the crystallization of the amorphous layer 12 can be promoted, and examples thereof include those made of an inorganic compound such as a metal, an oxide of the metal, a sulfide, or a fluoride. Among these, silicon oxide or aluminum oxide is preferable, silicon oxide is more preferable, and SiOx (x is 1.5 to 2) is particularly preferable.

  The thickness of the underlayer is not necessarily limited as long as crystallization during the heat treatment of the amorphous layer 12 can be promoted, but is preferably 1 nm or more, and more preferably 3 nm or more. By setting the thickness of the underlayer to 1 nm or more, crystallization of the amorphous layer 12 can be effectively promoted. If the thickness of the underlayer is about 5 nm, crystallization of the amorphous layer 12 can be sufficiently promoted, and if it is 10 nm or less, productivity and transparency can be improved.

The amorphous layer 12 is in an amorphous state at the stage of the conductive film material 10, and is crystallized by heat treatment to become a crystalline layer (that is, a crystalline transparent conductive film). The amorphous layer 12 is made of indium tin oxide, which is an oxide of indium and tin. In the indium tin oxide, tin is converted into an oxide (in terms of tin oxide of SnO ₂ , hereinafter the same). 5 to 9% by mass is contained. Examples of the oxide constituting the indium tin oxide include indium oxide, tin oxide, and a composite oxide of indium oxide and tin oxide.

  Thus, when the amorphous layer 12 is made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide, crystallization by heat treatment is easy and crystallized. The sheet resistance value can be low, and the increase in film thickness can be suppressed. Specifically, the film thickness is 15 to 25 nm, and the sheet resistance value when crystallization is 50 to 150 Ω / □, and crystallization by heat treatment can be facilitated. Moreover, according to such a thing, etching property can also be made favorable like the past. From the viewpoint of the ease of crystallization by heat treatment and the sheet resistance value when crystallization is performed, the content of tin in terms of oxide in the indium tin oxide is preferably 5.8% by mass or more, and exceeds 6% by mass. Is more preferable, and 6.5 mass% or more is still more preferable. Moreover, 8.9 mass% or less is preferable, 8.5 mass% or less is more preferable, and 8.3 mass% or less is further more preferable. Hereinafter, the content of tin oxide in terms of oxide of tin in indium tin oxide may be simply referred to as tin oxide content.

  The thickness of the amorphous layer 12 is not particularly limited as long as it is 15 to 25 nm, but is preferably 20 to 25 nm from the viewpoint of easy crystallization by heat treatment and optical characteristics such as transmittance. In addition, the sheet resistance value after crystallization of the amorphous layer 12 is not particularly limited as long as it is 50 to 150Ω / □. From the viewpoint of easiness of crystallization by A, 80 to 150Ω / □ is preferable, and 100 to 150Ω / □ is more preferable.

  The amorphous layer 12 is preferably made of only indium tin oxide, but can contain components other than indium tin oxide as required and within the limits not departing from the gist of the present invention. Examples of components other than indium tin oxide include oxides such as aluminum, zirconium, gallium, silicon, tungsten, zinc, titanium, magnesium, cerium, and germanium. The content of components other than indium tin oxide in the amorphous layer 12 is 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less in the entire amorphous layer 12. A mass% or less is particularly preferred.

  The conductive film material 10 can be a conductive film laminate in which a crystalline transparent conductive film made of crystalline indium tin oxide is stacked on a transparent substrate 11 by heat treatment. That is, the amorphous layer 12 is crystallized by heat treatment to form a crystalline layer (that is, a crystalline transparent conductive film), whereby a conductive film stack can be obtained.

  The heat treatment is preferably performed, for example, in the atmosphere at 100 to 150 ° C. for 30 to 180 minutes. By setting the heat treatment temperature to 100 ° C. or more and the heat treatment time to 30 minutes or more, the amorphous layer 12 can be effectively crystallized. Moreover, it can crystallize sufficiently by setting the heat treatment temperature to 150 ° C. and the heat treatment time to 180 minutes, and by setting the heat treatment temperature to 150 ° C. or less and 180 minutes or less, damage to the transparent substrate 11 and the like can be suppressed, and productivity is lowered Can also be suppressed.

FIG. 2 is a cross-sectional view showing an embodiment of the conductive film laminate 20 obtained by heat-treating the conductive film material 10. The conductive film laminate 20 includes, for example, a transparent base material 11 and a crystalline layer 21 laminated on the transparent base material 11. As already described, the crystalline layer 21 is formed by crystallizing the amorphous layer 12 by heat treatment, and functions as a crystalline transparent conductive film.
When obtaining a conductive film laminate in which a large number of transparent electrodes patterned by etching are formed on the transparent conductive film, the amorphous layer 12 of the conductive film material 10 is etched at an amorphous stage. A crystalline layer 21 which is a crystalline transparent conductive film is formed by performing desired patterning, and crystallizing the patterned amorphous layer (that is, a large number of amorphous transparent electrodes) by heat treatment. (That is, a large number of transparent electrodes in a crystalline state). In this way, first, an indium tin oxide film in an amorphous state that does not take a long time for etching is formed, and this indium tin oxide film in the amorphous state is etched to obtain a large number of films. After forming the transparent electrode, it is crystallized by heat treatment, so that it takes no extra time for the etching process for forming the transparent electrode, and a good conductive film in which the pattern shape of many transparent electrodes becomes a desired shape A laminate can be obtained.
After the amorphous layer is crystallized by heat treatment to form a crystalline transparent conductive film, the crystalline transparent conductive film is subjected to desired patterning by etching to form a large number of transparent electrodes and the like. May be.

The crystalline layer 21 is made of indium tin oxide, which is an oxide of indium and tin, and contains 5.5 to 9% by mass of tin in terms of oxide in the indium tin oxide. The tin oxide content in terms of oxide of tin in the indium tin oxide is preferably 5.8% by mass or more, more preferably more than 6% by mass, and even more preferably 6.5% by mass or more. Moreover, 8.9 mass% or less is preferable, 8.5 mass% or less is more preferable, and 8.3 mass% or less is further more preferable. Note that indium tin oxide preferably has a crystal structure of indium oxide (In ₂ O ₃ ), and tin is preferably substituted at the site of indium.

  The film thickness of the crystalline layer 21 is not particularly limited as long as it is 15 to 25 nm, but is preferably 15 to 25 nm from the viewpoint of optical properties such as crystallization ease and heat transmittance during the production thereof. 25 nm is more preferable. In addition, the sheet resistance value of the crystalline layer 21 is not particularly limited as long as it is 50 to 150Ω / □, but it is possible to suppress the decrease in transmission speed during the operation accompanying the increase in the size of electronic devices such as a touch panel and to facilitate crystallization. From the viewpoint, 80 to 150Ω / □ is preferable, and 100 to 150Ω / □ is more preferable.

  Such a conductive film laminate 20 is suitably used for an electronic device. In particular, since the sheet resistance value of the crystalline layer 21 which is a crystalline transparent conductive film is as low as 150Ω / □ or less, and the transmission speed when the size is increased is small, it is suitably used for an enlarged electronic device.

  Examples of the electronic device include a liquid crystal display device, a plasma display device, a touch panel device, and the like, and a touch panel device is particularly preferable. The touch panel device includes, for example, a display unit and a touch panel unit disposed on the front surface of the display unit. The conductive film laminate 20 is used as a transparent electrode substrate having a transparent electrode in such a touch panel portion. The touch panel unit may be either a resistive film type that specifies a touch position by contacting upper and lower electrodes, or a capacitive coupling type that senses a change in capacitance.

Next, the manufacturing method of the raw material 10 for electrically conductive films and the electrically conductive film laminated body 20 is demonstrated.
The conductive film material 10 can be produced by forming an amorphous layer 12 made of indium tin oxide in an amorphous state after forming a base layer on the transparent substrate 11 as necessary. The film forming method is not necessarily limited, but a sputtering method, an ion plating method, or a vacuum evaporation method is preferable, and a sputtering method is particularly preferable.

When applying the sputtering method, it is preferable to use a sputtering target made of a sintered body of indium tin oxide obtained by mixing and sintering tin oxide (SnO ₂ ) and indium oxide (In ₂ O ₃ ). Moreover, it is preferable that a sputtering target contains 5.5-9 mass% of tin in oxide conversion in indium tin oxide. The tin oxide content in terms of oxide of tin in the indium tin oxide is more preferably 5.8% by mass or more, further preferably more than 6% by mass, and particularly preferably 6.5% by mass or more. Moreover, 8.9 mass% or less is more preferable, 8.5 mass% or less is further more preferable, and 8.3 mass% or less is especially preferable.

  The amorphous layer 12 is formed, for example, by sputtering while introducing a mixed gas obtained by mixing 0.5 to 10% by volume, preferably 0.8 to 6% by volume, of oxygen gas into argon gas. Preferably it is done. By performing sputtering while introducing such a mixed gas, an amorphous layer 12 which is amorphous and easy to crystallize by heat treatment and has a low sheet resistance when crystallized is formed. it can.

Prior to the formation of the amorphous layer 12, the vacuum in the sputtering apparatus is evacuated to 5 × 10 ⁻⁴ Pa or less, preferably 9 × 10 ⁻⁵ Pa or less, so that moisture and transparency in the sputtering apparatus can be reduced. It is preferable to have an atmosphere from which impurities such as moisture or organic gas generated from the substrate 11 or the like are removed. By reducing the presence of moisture and organic gas during film formation, crystallization by heat treatment is easy, and a sheet having a low sheet resistance when crystallized can be easily obtained.

  FIG. 3 shows an example of the relationship between the oxygen gas flow rate during the formation of the amorphous layer 12 and the sheet resistance value before and after the heat treatment of the amorphous layer 12 (when the tin oxide content in the target is 5 mass%). ).

  The amorphous layer 12 is formed by forming a 50 Å thick SiOx film (x is 1.5 to 2) as a base layer on a PET film having a thickness of 100 μm as the transparent substrate 11. A SiOx film as a base layer was formed to a thickness of 255 angstroms.

  Specifically, the SiOx film is formed by performing AC magnetron sputtering at a pressure of 3.7 Pa while introducing a mixed gas obtained by mixing 11 volume% oxygen gas into argon gas using a boron-doped polysilicon target. did. In addition, the amorphous layer 12 uses a sputtering target made of indium tin oxide containing 5.0% by mass of tin in terms of oxide, introduces a mixed gas of argon gas and oxygen gas, and flows oxygen gas. The film was formed by performing DC magnetron sputtering at a pressure of 0.8 Pa.

  As can be seen from FIG. 3, the sheet resistance value becomes the minimum value when the oxygen gas flow rate during the formation of the amorphous layer becomes a specific value. The sheet resistance value increases as the flow rate decreases and the flow rate increases as compared to the flow rate when the sheet resistance value becomes the minimum value. Although not shown, crystallization by heat treatment becomes more difficult as the flow rate is lower than the flow rate when the sheet resistance value is the lowest value. On the other hand, as the flow rate increases compared to the flow rate at which the sheet resistance value becomes the minimum value, the sheet resistance value is likely to increase with the passage of time in year units after the heat treatment.

  From this, the flow rate of oxygen gas when forming the amorphous layer 12 has a range of 0.6 to 1.4 times the flow rate when the sheet resistance value after crystallization becomes the minimum value. The range of 0.7 to 1.3 times is more preferable, and the range of 0.8 to 1.2 times is particularly preferable. Accordingly, in the actual film formation of the amorphous layer 12, the flow rate of the oxygen gas when the sheet resistance value after crystallization becomes the minimum value is obtained in advance, and the flow rate of the oxygen gas is determined. It is preferable to adjust the flow rate of the oxygen gas so as to be within the above range. Since the optimum flow rate varies slightly depending on the film forming apparatus, a film having a low sheet resistance value after crystallization can be effectively formed particularly by such a method.

  FIG. 4 shows an example of the relationship between the tin oxide content in terms of oxide of tin in the sputtering target and the oxygen gas flow rate when the sheet resistance value after crystallization of the amorphous layer 12 becomes the minimum value. FIG. In FIG. 4, the tin oxide content in terms of tin oxide is 2% by mass, 3% by mass, 5% by mass, 7% by mass, 8.8% by mass, 10% by mass, and 12% by mass. % Cases are shown. The film forming conditions were basically the same as the above conditions. For example, when the tin oxide content in terms of tin oxide is 3% by mass, the flow rate when the sheet resistance value after crystallization becomes the minimum value is 1.0% by volume. In the case of 10% by mass, the flow rate is 1.4% by volume.

  The conductive film laminate 20 can be manufactured by heat-treating such a conductive film material 10. That is, the amorphous layer 12 is crystallized by heat treatment to obtain a crystalline layer 21 that is a crystalline transparent conductive film. The heat treatment is preferably performed, for example, in the atmosphere at 100 to 150 ° C. for 30 to 180 minutes. By setting the heat treatment temperature to 100 ° C. or more and the heat treatment time to 30 minutes or more, the amorphous layer 12 can be effectively crystallized. The heat treatment temperature is 150 ° C. or less, and the heat treatment time is 180 minutes or less, so that sufficient crystallization can be achieved. Productivity can also be improved.

Hereinafter, embodiments of the present invention will be specifically described with reference to examples. Sample No. 6, 8, and 10 to 12 are examples of the present invention. 1-5, 7, 9, 13-18 are comparative examples of the present invention. In addition, this invention is not limited by these Examples.
The film thickness of the amorphous layer is a value obtained from optical characteristics or sputtering film formation rate and sputtering time. In other words, the film thickness of the amorphous layer prepared at the same sputtering film formation rate and sputtering conditions employed in the sample preparation is measured with a film thickness meter, and the film thickness formed per unit time of the sputtering time is obtained. It is a value obtained by calculating the film thickness from the sputtering time in sample preparation. The film thickness is a geometric thickness.

Sample No. 1-No. 18 was produced by the following method.
An SiOx film (x is 1.5 to 2) having a thickness of 32 angstroms was formed as an underlayer on a PET film having a thickness of 100 μm, which was a transparent substrate. The SiOx film was formed by performing AC magnetron sputtering at a pressure of 3.7 Pa while introducing a mixed gas obtained by mixing 11% by volume of oxygen gas into argon gas using a boron-doped polysilicon target. The thickness of the SiOx film was adjusted by adjusting the power density and the sputtering time.

  On the PET film on which the SiOx film is formed, as a film forming process of the amorphous layer, a target made of indium tin oxide containing a predetermined amount of tin in terms of oxide is used, and argon gas and oxygen gas are predetermined. While introducing the mixed gas mixed at the ratio of, DC magnetron sputtering was performed at a pressure of 0.8 Pa to form an amorphous layer, and a conductive film material was manufactured.

The details of the film formation conditions for the amorphous layer are as shown in Table 1. The target is a sintered body obtained by mixing and sintering tin oxide (SnO ₂ ) and indium oxide (In ₂ O ₃ ), and the content in terms of tin oxide (tin oxide content) In which 3 to 12% by mass was used. The flow rate of the oxygen gas was adjusted in advance so that the flow rate when the sheet resistance value after crystallization became the minimum value was obtained in advance. The film thickness of the amorphous layer was adjusted by adjusting the power density and the sputtering time. In addition, you may estimate that content in the oxide conversion of the tin in an amorphous layer is equivalent to content in the oxide conversion of the tin in a target.

  The obtained conductive film material was subjected to a heat treatment at 145 ° C. for 60 minutes in the air as a heat treatment step for the amorphous layer, to produce a conductive film laminate.

  Sample No. manufactured using a target containing tin oxide at a content ratio as shown in Table 1. 1-No. Table 1 shows the sheet resistance value (Ω / □), the measurement result of the film thickness (Å) of the amorphous layer, and the evaluation of the crystallinity of the amorphous layer for each of the 18 conductive film laminates.

(Sheet resistance value)
Each conductive film laminate was cut into a size of 100 mm × 100 mm, and a sheet resistance value (Ω / □, that is, Ω / square) was measured by a four probe method using Lorester (trade name, manufactured by Mitsubishi Chemical Corporation).

(crystalline)
The resistance value was measured before and after immersing each conductive film laminate in a 25 ° C. HCl solution (concentration 1.5 mol / L) for 3 minutes, and the resistance value change rate (resistance value after immersion / resistance value before immersion) was determined. Asked. As already described, the resistance value change rate is an index of crystallinity, and those having a resistance value change rate of 200% or less have crystallinity. In the table, a resistance value change rate of 200% or less is indicated by “◯”, and a resistance value change rate exceeding 200% is indicated by “X”.

  When the content of tin in terms of oxide is less than 5.5% by mass, the crystallinity during heat treatment is good even if the film thickness is reduced to 25 nm (250 angstroms) or less, but after heat treatment (after crystallization) ) Sheet resistance value exceeds 150Ω / □. On the other hand, when the content in terms of oxide of tin exceeds 9% by mass, for those having a film thickness exceeding 25 nm, the crystallinity during heat treatment is good, and the sheet resistance value after heat treatment is also 150 Ω / □ or less. Although a sufficiently low value can be obtained, for those with low transmittance and a film thickness of 25 nm or less, the crystallinity during heat treatment is not sufficient, and the sheet resistance value after heat treatment exceeds 150 Ω / □. It becomes. When the content of tin in terms of oxide is 5.5 to 9% by mass, the crystallinity during heat treatment is good even when the film thickness is as thin as 25 nm or less, and the sheet resistance value after heat treatment is also 150 Ω / □ or less. A sufficiently low value is obtained.

According to the present invention, it is possible to obtain a conductive film laminate having a crystalline layer having a low sheet resistance value and a suppressed increase in film thickness. Such a conductive film laminate is particularly large for electronic equipment. It is useful as a conductive film laminate used for a touch panel device.
The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2012-111777 filed on May 15, 2012 are incorporated herein by reference. .

  DESCRIPTION OF SYMBOLS 10 ... Raw material for electrically conductive films, 11 ... Transparent base material, 12 ... Amorphous layer, 20 ... Conductive film laminated body, 21 ... Crystalline layer

Claims (8)

A conductive film material having a transparent base material and an amorphous layer made of indium tin oxide laminated on the transparent base material,
The amorphous layer is made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide, the film thickness is 15 to 25 nm, and the sheet resistance value when crystallized is 50 to 150Ω. A conductive film material characterized by being / □.   The conductive film material according to claim 1, wherein the amorphous layer is made of indium tin oxide containing tin in excess of 6 mass% in terms of oxide. A conductive film laminate having a transparent substrate and a crystalline layer made of indium tin oxide laminated on the transparent substrate,
The crystalline layer is made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide, and has a film thickness of 15 to 25 nm and a sheet resistance value of 50 to 150Ω / □. A conductive film laminate.   The conductive film laminate according to claim 3, wherein the crystalline layer is made of indium tin oxide containing tin in excess of 6 mass% in terms of oxide.   An electronic apparatus comprising the conductive film laminate according to claim 3.   Sheet when the film thickness is 15 to 25 nm and crystallized by sputtering using a sputtering target made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide on a transparent substrate The manufacturing method of the raw material for electrically conductive films characterized by having the film-forming process which forms the amorphous layer from which resistance value becomes 50-150 ohms / square. Sheet when the film thickness is 15 to 25 nm and crystallized by sputtering using a sputtering target made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide on a transparent substrate A film forming step of obtaining a conductive film material by forming an amorphous layer having a resistance value of 50 to 150Ω / □;
A heat treatment step of heat-treating the conductive film material to crystallize the amorphous layer into a crystalline layer;
The manufacturing method of the electrically conductive film laminated body characterized by having. Sheet when the film thickness is 15 to 25 nm and crystallized by sputtering using a sputtering target made of indium tin oxide containing 5.5 to 9% by mass of tin in terms of oxide on a transparent substrate A film forming step of obtaining a conductive film material by forming an amorphous layer having a resistance value of 50 to 150Ω / □;
Patterning the amorphous layer of the conductive film material by etching;
Heat-treating the patterned conductive film material to crystallize the amorphous layer into a crystalline layer; and
The method for producing a conductive film laminate according to claim 7, comprising:

Images