JPH0877845A - Method of manufacturing and reforming film - Google Patents

Abstract

PURPOSE: To provide a method of manufacturing a low-resistance high permeability transparent conductive film. CONSTITUTION: A transparent conductive film is irradiated with a particle beam consisting of at least one element among He, Ne, Ar, Kr, and Xe during manufacture or after manufacture of a tin-added indium oxide (ITO) film, an indium oxide film, or a tin oxide film. The energy of a particle beam is decided, according to film growth temperature or crystallization temperature. In case that the difference to the crystallization temperature is large, the energy of a particle beam is enlarged. In case that the difference to the crystallization temperature is small, the energy of a particle beam is made small.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a film and a method for modifying a film. Among them, it particularly relates to a method for producing a transparent conductive film used as a transparent electrode for a liquid crystal display device or a solar cell.

[0002]

2. Description of the Related Art Transparent conductive films are widely used for transparent electrodes in liquid crystal display devices, solar cells and the like.

The transparent conductive film that has been put to practical use and is being researched so far has been found to contain Sn-added In ₂ O ₃ (hereinafter referred to as “IT”).
O "and abbreviated), ZnO with the addition of SnO _2, Al
(Hereinafter abbreviated as “AZO”) and the like. Among them, the ITO film is mostly used for the display device because of its low resistance and good workability.

ITO is a degenerate n-type semiconductor having a wide bandgap of about 3.6 eV and having electrons in the donor level band generated by oxygen deficiency (or Sn doping as a donor) as carriers.

The transparent conductive film is generally required to have low resistance and high light transmittance for its use. In order to meet this requirement, many studies have been made on the ITO film regarding the film forming method, the film forming condition, and the heat treatment condition. Then, the amount of Sn in the film, the substrate temperature during the film production, the gas pressure, or the heat treatment temperature after the film production, the time,
Low resistance has been promoted by optimizing gas and the like.
It has been known that, in general, an ITO film has a lower resistance and a higher transparency as the substrate temperature during film preparation is higher and the heat treatment temperature is higher. For example, Thin Solid Films Vol. 226, p. 104, 1933 (T
thin Solid Films Vol. 226,
p. 104 (1993)), it was reported that ITO having a specific resistance of 1.3 × 10 ⁻⁴ Ωcm was obtained at a substrate temperature of 300 ° C.

In addition, Journal of Applied Physics Vol. 71, p. 3356, 1992 (Jou
rnal of Applied Physics V
ol. 71, p. 3356 (1992)), it was reported that an ITO film having a specific resistance of 3.1 × 10 ⁻⁴ Ωcm was obtained at a substrate temperature of 150 ° C.

[0007]

In recent years, liquid crystal display devices, which are the main uses of transparent conductive films, have been advanced in high definition, low power consumption, and large screen. In order to increase the definition of the display screen, it is necessary to reduce the pixel area, which is achieved by reducing the width of the transparent electrode.
In order to supply the sufficient electric power for driving the pixel while reducing the width of the transparent electrode, it is necessary to reduce the resistance of the transparent conductive film itself that constitutes the transparent electrode. Further, in order to reduce the power consumption, it is necessary to reduce the resistance of the transparent electrode and improve the light transmittance (Note: this leads to the reduction of the power consumption of the backlight). Therefore, further reduction of resistance of the transparent conductive film and further improvement of light transmittance are being demanded.

[0008] Further, the solar cell is required to improve not only the efficiency of converting light energy into electric energy but also the efficiency of finally being taken out as electric energy to the outside. Therefore, the transparent conductive film has been required to have further improved transmittance and lower resistance.

In the polycrystalline ITO film, the resistance component due to grain boundary scattering is an obstacle to the reduction of resistance. Parameters that characterize polycrystallinity include crystal grain size, orientation, and segregation of impurities at grain boundaries. Generally, as the crystal grain size increases, grain boundary resistance decreases and resistance decreases. Conversely speaking, if the crystal grain size of the ITO film can be increased (increased crystallinity), the grain boundary resistance can be reduced to lower the resistance. Further, if the crystal grain size is increased, irregular reflection at grain boundaries will be eliminated, and the transmittance should be improved.

However, in the research so far, the crystal grain size of the ITO film cannot be extremely increased, and the specific resistance of the ITO film is 2.5 × 10 ⁻⁴ Ωcm (150 ° C.), 1.0.
The limit was about × 10 ⁻⁴ Ωcm (300 ° C.).

In addition, in the current electronic devices, it has been widely required to produce a thin film in a desired crystalline state while satisfying various constraints (for example, temperature).

An object of the present invention is to provide a method for producing a transparent conductive film having high crystallinity.

An object of the present invention is to provide a method for producing a transparent conductive film having a low resistance and a high light transmittance.

An object of the present invention is to provide a liquid crystal display device with high definition and low power consumption, or for a solar cell with high electromotive force.
It is to provide a method for manufacturing a transparent conductive film.

An object of the present invention is to provide a method for producing a film whose crystal state can be controlled and a method for modifying the film.

[0016]

Means for Solving the Problems The inventors of the present application produced a film (in particular, a transparent conductive film) while changing the conditions variously, and examined its characteristics from various angles. As a result, the film properties (especially crystallinity, resistivity,
The transmittance is the crystallization temperature of the film, the energy of the particle beam with which the film is irradiated during (or after) the film formation, and the temperature of the film during the formation (during film formation) In some cases, the term "deposition temperature" in the text) has a significant effect.

Further, the behavior of the film characteristics of the film with respect to the particle beam irradiation voltage, the film forming temperature, etc., is a relationship between the film crystallization temperature and two effects (crystallization promoting effect and sputtering effect) due to the particle beam irradiation. The present inventor has come to speculate that this is due to the above. The effects of particle beam irradiation include the crystallization promoting effect and the sputter effect, which are contradictory to each other. When the film formation temperature is sufficiently lower than the crystallization temperature, the film becomes amorphous. When a film in an amorphous state is irradiated with a particle beam, the crystallization promoting effect improves the crystallinity of the film. On the other hand, when the film formation temperature is higher than the crystallization temperature, the film has high crystallinity. When a film having high crystallinity is irradiated with a particle beam, the crystallinity is rather lowered due to the sputtering effect. Crystallization temperature is an IT manufactured by changing the substrate temperature.
This is the temperature at which a diffraction peak indicating the presence of a crystal plane begins to be discontinuous in the X-ray diffraction pattern of the O film. The crystallization acceleration effect means that energy is introduced into the film by particle beam irradiation,
This is an effect of promoting the surface migration of sputtered particles and increasing the crystallinity of the film. The sputter effect is the effect that the irradiated particle beam strikes the film surface and reduces the crystallinity.

The present invention has been made based on such knowledge.

The present invention has been made in order to achieve the above object. As a first aspect thereof, in the method for producing a film, the film is a tin-added indium oxide film, an indium oxide film or a tin oxide film. While forming the film in an atmosphere containing oxygen gas, He, Ne, Ar, Kr,
Irradiating with a particle beam made of at least one element of Xe is provided.

The film formation may be performed by sputtering.

As a second aspect of the present invention, in the method for producing a film, while the film is being formed, the crystallization temperature of the film and the temperature of the film being formed are formed on the film being formed. And the irradiation energy determined based on the difference between He, Ne, Ar,
There is provided a method for producing a film, which comprises irradiating a particle beam made of at least one element of Kr and Xe.

When the temperature of the film being formed is lower than the crystallization temperature, the irradiation energy is increased as the difference between the crystallization temperature and the temperature of the film being formed is larger. It is preferable to make it large.

In the first and second aspects, it is preferable that the particle beam includes at least one of a neutral particle beam and a charged particle beam.

A third aspect of the present invention is characterized in that, in the method for modifying a film, the film is irradiated with a particle beam composed of at least one element of He, Ne, Ar, Kr and Xe. A method of modifying a membrane is provided.

The film is a tin-added indium oxide film, an indium oxide film, or a tin oxide film, and it is preferable that the particle beam irradiation is performed in an atmosphere containing oxygen gas.

The irradiation energy of the particle beam is preferably determined based on the difference between the crystallization temperature of the film and the temperature of the film at the time of the particle beam irradiation.

When the temperature of the film being formed is lower than the crystallization temperature, the irradiation energy is increased as the difference between the crystallization temperature and the temperature of the film being formed is larger. It is preferable to make it large.

The particle beam preferably includes at least one of a neutral particle beam and a charged particle beam.

[0029]

[Function] The resistance of the film (in particular, the transparent conductive film such as ITO),
The transparency is related to the crystal state such as the surface morphology of the film, the presence or absence of crystallinity, the crystal grain size, the presence or absence of orientation, and the strength of orientation.
As in the above structure, H
By irradiating the film with a particle beam made of at least one element of e, Ne, Ar, Kr, and Xe, its crystalline state can be changed. The transparent conductive film such as ITO is more preferably treated in an oxygen atmosphere. When the film formation temperature is lower than the crystallization temperature, the irradiation energy is preferably increased as the difference between the crystallization temperature and the film formation temperature becomes larger.

The film has different crystallinity depending on the film forming temperature. For example, an ITO film produced at a substrate temperature of 150 ° C. without being irradiated with a particle beam is an amorphous film, has no crystal grains, and has no orientation. on the other hand,
When an ITO film is formed while irradiating a particle beam accelerated at an acceleration voltage of 20 to 100 V at a substrate temperature of 150 ° C., it becomes a crystalline film, and the crystal grain size and orientation change depending on the incident energy. Due to the change in the crystalline state from the amorphous film to the crystalline film due to the irradiation of the particle beam, the specific resistance of the ITO film decreases and the transmittance increases.

In the actual film formation process, the temperature of the film is often measured and controlled rather than directly measured and controlled. Although depending on the apparatus used for film formation, the substrate has a large heat capacity as compared with the film formed on the substrate, and therefore, in many cases, it can be considered that the film formation temperature is substantially equal to the temperature of the substrate. Therefore, the adjustment of the irradiation energy described above may be performed based on the difference between the substrate temperature and the crystallization temperature.

[0032]

Embodiments of the present invention will be described below with reference to the drawings.

[Example 1] A procedure for forming a transparent conductive film of this example will be described.

Here, the sputtering apparatus shown in FIG. 1 was used. This sputtering apparatus includes a vacuum chamber 1, an irradiation particle beam generator 2, a sputtering particle beam generator 3, a substrate holder 4, a sputtering target holder 5, an atmosphere gas introduction pipe 6, a vacuum pump 7, and a substrate 8.

The sputtered particle beam generating unit 3 irradiates the sputter target 9 with a sputtered particle beam (X in the present embodiment).
(e particle beam) 10 is generated.

The irradiation particle beam generator 2 irradiates the transparent conductive film with the irradiation particle beam 11 during the film formation (or after the film formation). The irradiation particle beam generator 2 accelerates the element in the state of charged particles, but the irradiation particle beam 11 is neutralized by thermal electrons from the filament, and the irradiation particle beam 11 is a neutral particle beam.

Although not specifically described, this apparatus also has a mechanism for adjusting the temperature of the substrate 8. The temperature is measured on the surface of the substrate 8 on which the film is formed. In reality, it is ideal to measure and control the temperature of the film to be produced, but it is difficult to accurately measure and control the temperature of the film being produced. Therefore, in a normal sputtering device, the temperature of the substrate is measured and controlled. In the present embodiment as well, the substrate temperature is measured and treated as the film temperature (film forming temperature). As described above, there is no practical problem even if such handling is performed.

A procedure for forming the transparent conductive film will be described.

The ITO target 9 is fixed to the sputter target holder 5, and the substrate 8 is fixed to the substrate holder 4.
Then, the vacuum chamber 1 is evacuated by the vacuum pump 7, and instead,
Atmosphere gas is introduced from the atmosphere gas introduction pipe 6. The ITO target 9 is sputtered with the sputtered particle beam 10 to deposit an ITO film on the substrate 8. This deposition was performed while irradiating the surface of the ITO film being deposited on the substrate 8 with the particle beam 11.

Materials used and detailed conditions are as follows.

Material of Substrate 8: Glass Temperature of Substrate 8: Room Temperature to 350 ° C. Irradiated Particle Beam 11: Xe Particle Beam Irradiation Voltage, Current: (20 V, 0.3 mA) (100 V, 10 mA) ITO Target 9: SnO ₂ In ₂ O ₃ atmosphere gas containing 10 wt%: O ₂ Film thickness of ITO film produced: 1400 Å SEM image of the obtained ITO film is shown in FIG. Figure 2
When (a) is not irradiated with a particle beam, (b) in FIG.
This is a case where the particle beam (irradiation voltage: 20 V, current 0.3 mA) is irradiated. Both substrate temperatures are 150 ° C.

The crystallization temperature of the ITO film under the conditions of this embodiment is about 160.degree. When the substrate temperature is 160 ° C. or lower, the formed ITO film should be in an amorphous state. However, as can be seen from FIG.
When the Xe particle beam was irradiated, the crystallization of the ITO film was remarkably promoted even though the substrate temperature was 150 ° C. From this, it is understood that the irradiation of the Xe particle beam during the production of the ITO film changes the surface morphology and orientation of the ITO film.

The mobility of the ITO film was 23 cm ² · V ^-1 · sec ^-1 without Xe particle beam irradiation. On the other hand, when irradiated with Xe particle beam, it is 44 cm ² · V ^-1 ·
It was sec ^-1 , which was remarkably improved with the promotion of crystallization.

Next, in order to confirm the crystalline state of the ITO film, an X-ray diffraction pattern was measured. The result is shown in FIG. 3A shows the case where the Xe particle beam was not irradiated, and FIG. 3B shows the Xe particle beam (irradiation voltage: 20 V, current: 0.
3A), FIG. 3C shows the case where Xe particle beam (irradiation voltage: 100V, current: 10mA) is irradiated. The substrate temperature is 150 ° C. in each case.

In FIG. 3 (a), no diffraction peak showing the existence of crystal planes appears. On the other hand, in FIG. 3B, a diffraction peak showing the existence of the crystal plane appeared. Thus, the results of X-ray diffraction also confirmed that the crystallization of the ITO film was promoted by Xe particle beam irradiation. A diffraction peak showing the existence of a crystal plane also appears in FIG. 3C, but the number and intensity are low. Compared to FIG. 3 (b), the crystallinity was rather reduced. That is, the crystallinity is as follows: Xe particle beam irradiation is not performed, and Xe particle beam irradiation is performed (irradiation voltage: 100 V, current:
10 mA), with Xe particle beam irradiation (irradiation voltage: 20 V,
Current: 0.3 mA).

Such a variation in crystallinity is caused by the substrate temperature 15
It is considered that 0 ° C. is the almost limit temperature at which the amorphous film becomes a crystalline film. As described above, the crystallization temperature of the ITO film under the conditions of this embodiment is about 160 ° C.
At a substrate temperature of 150 ° C., the difference from the crystallization temperature is small, so that only a small amount of energy flows into the film to strongly promote crystallization. This is considered to be the reason why the crystallinity of the film was improved when the particle beam was irradiated with the irradiation voltage of 20V. On the other hand, the reason why the crystallinity was rather deteriorated when the particle beam with the irradiation voltage of 100 V was irradiated is considered to be that the energy of the particle beam was too high and the sputter effect was stronger than the crystallization promoting effect.

FIG. 4 shows the result of measurement of the relationship between the substrate temperature at the time of film formation and the specific resistance of the obtained ITO film. The “assist irradiation” described in the figure means the irradiation particle beam 11. Considering the results of FIG. 2 and FIG. 3, it seems that the decrease of the specific resistance is accompanied by the improvement of the crystallinity.

When the substrate temperature was 250 ° C. or lower, the specific resistance decreased when the Xe particle beam was irradiated. In the vicinity of room temperature to about 100 ° C., the specific resistance is lowest when the particle beam with the irradiation voltage of 100 V is irradiated. This is probably because the temperature difference (ie, energy difference) from the crystallization temperature was large, and the energy of the particle beam was effectively used to promote crystallization. When the temperature is higher than about 100 ° C., the resistivity at the irradiation voltage of 20 V is lower than that at the irradiation voltage of 100 V. This is presumably because, as described in the description of FIG. 3, the temperature difference from the crystallization temperature is small, so that the high sputter effect appears when the energy of the particle beam is high. Such a result agrees with the results shown in FIGS. 2 and 3.

When the substrate temperature is 300 ° C. or higher, it does not decrease (or increases) even when the particle beam is irradiated. The condition that the substrate temperature is 300 ° C. or higher is a condition that a film with high crystallinity can be formed without irradiating with a particle beam. Since the film formed under such conditions (300 ° C.) originally has high crystallinity, even if the particle beam is irradiated, crystallization cannot be further promoted, and it is considered that the sputter effect is simply exhibited. .

FIG. 5 shows the results of measuring the relationship between the transmittance of the ITO film and the presence or absence of Xe particle beam. The substrate temperature is 150 ° C. in each case. Considering the results of FIGS. 2 and 3, it is considered that the improvement of the transmittance of visible light is caused by the improvement of the crystallinity.

As can be seen from FIG. 5, when the ITO film was produced while irradiating the Xe particle beam, the transmittance was generally increased.

When a film having low crystallinity (for example, an amorphous film) is irradiated with a particle beam as described above, the crystallinity of the ITO film is improved and the resistance is lowered. On the other hand, when a film having a high crystallinity (for example, a film produced at a high substrate temperature) is irradiated with a particle beam, the crystallinity of the film is rather decreased, which causes an increase in resistance and a decrease in transmittance. Become. Such behavior of the film characteristics of the ITO film with respect to the particle beam irradiation voltage, the substrate temperature, and the like supports the above-mentioned inference by the inventor of the present application (described at the beginning of the column of means for solving the problem). Therefore, when the film formation temperature (here, the substrate temperature) is lower than the crystallization temperature, by irradiating a particle beam having energy corresponding to the difference between the film formation temperature (substrate temperature) and the crystallization temperature, The crystallinity can be further enhanced. When this difference is small, low-energy particle beams may be irradiated, and when the difference is large, high-energy particle beams may be irradiated.

If the inventor's reasoning is correct, the crystallinity of the ITO film may be improved even if the ITO film after the production is irradiated with the irradiation particle beam 11, as in the case of irradiation during the production of the ITO film. Should occur. In fact, although no data is shown here, similar improvement in crystallinity, reduction in resistance, and improvement in light transmittance were observed according to the results of experiments conducted by the present inventors.

The crystallization temperature of the ITO film changes depending on the atmospheric gas during film formation. In this example, oxygen was used as the atmosphere gas, and the crystallization temperature was about 160 ° C. When water is used as the atmospheric gas, the crystallization temperature is about 220 ° C. In this case, the optimum temperature at which the effect of improving the crystallinity and reducing the resistance by the particle beam irradiation appears is also shifted to the high temperature side. Considering the influence on other process parts,
When it is desired to enhance the crystallinity at a temperature as low as possible, it is preferable to use oxygen gas as the atmosphere gas.

[Embodiment 2] In this embodiment 2, the irradiated particle beam 1 is used.
1 is an example in which an ITO film is formed by using an element different from that in Example 1. The apparatus used and other experimental conditions are the same as in Example 1.

As the irradiation particle beam 11, He, Ne, A
r, Kr and oxygen were used alone. Irradiated particle beam 1
The irradiation voltage of 1 is 20 V and the current is 0.3 mA. The substrate temperature was 150 ° C.

Table 1 shows the results of measuring the specific resistance and the transmittance of light having a wavelength of 500 nm for the obtained ITO film.

[0058]

[Table 1]

As can be seen from Table 1, He, Ne, A
When prepared while irradiating the particle beam of any one element of r and Kr, an ITO film having low resistance and high transparency was obtained. This is probably because the crystallinity of the ITO film was improved as described above. As described above, the result that the crystallinity is similarly improved even when the type of the irradiated particle beam 11 is changed supports the speculation by the inventor of the present application.

However, although the ITO film produced while irradiating the irradiation particle beam 11 with the oxygen particle beam tends to improve the transmittance, it cannot be said that the resistance is lowered. It is not clear why oxygen particle irradiation does not reduce the resistance, but this is related to the fact that He, Ne, Ar, Kr (and Xe) are inert gases, while oxygen is an active gas. Conceivable.

[Embodiment 3] In this embodiment 3, the irradiation particle beam 1 is used.
In this example, a charged particle beam is used as 1. Equipment used,
Other experimental conditions are the same as in Example 1.

The irradiated particle beam 11 includes He, Ne, Ar,
A charged particle beam of any one element of Kr and Xe was used. The irradiation voltage of the irradiation particle beam 11 is 20 V and the current is 0.3.
mA. The substrate temperature was 150 ° C.

Table 2 shows the results of measuring the specific resistance and the transmittance of light having a wavelength of 500 nm for the obtained ITO film.

[0064]

[Table 2]

As can be seen from Table 2, He, Ne, A
The ITO film formed by irradiating the particle beam of any one element of r, Kr, and Xe has low resistance and high transmittance.
This is probably because the crystallinity of the ITO film was improved. As described above, the result that the crystallinity is improved almost in the same manner regardless of whether the irradiated particle beam 11 has an electric charge is
This supports the assumption made by the inventor of the present application.

[Embodiment 4] This embodiment 4 is an example in which a plastic substrate is used as the substrate 8 and an ITO film is formed thereon. The apparatus used and other experimental conditions are the same as in Example 1.

Table 3 shows the results of measuring the specific resistance and the transmittance of light having a wavelength of 500 nm for the obtained ITO.
It was shown to.

[0068]

[Table 3]

As can be seen from Table 3, the ITO film formed on the plastic substrate also has low resistance and high transmittance due to the irradiation of the particle beam 11. in this way,
The result that the crystallinity is improved irrespective of the type of substrate used supports the inventor's speculation.

[Embodiment 5] This embodiment 5 is an example in which In ₂ O ₃ or SnO ₂ is used as the sputtering target 9. The apparatus used is the same as in Example 1.

As the irradiation particle beam 11, Xe particle beam (irradiation voltage: 20 V, current 0.3 mA) was used. The substrate temperature was room temperature to 500 ° C. Other conditions are as in Example 1.
Is the same as.

FIG. 6 shows the specific resistance of the obtained In ₂ O ₃ film,
The relationship with the substrate temperature is shown. As can be seen from FIG. 6, Xe
The decrease in specific resistance due to particle beam irradiation occurred in the region of 250 ° C. or lower.

FIG. 7 shows the specific resistance of the SnO ₂ film without Xe particle beam irradiation, and the SnO ₂ film prepared while being irradiated with Xe particle beam.
The substrate temperature dependence of the resistivity of the _two films is shown. As can be seen from FIG. 7, the decrease in the specific resistance due to Xe particle beam irradiation occurred when the substrate temperature was 450 ° C. or lower.

Although no particular data is shown, In ₂ O ₃ , Sn
The transmittance of both O ₂ and the transparency was increased by the Xe particle beam irradiation.

An experiment of irradiating a Xe particle beam in an oxygen atmosphere was also conducted after the In ₂ O ₃ film and the SnO ₂ film were formed.
Although no data is shown, the results show that the resistance of the In ₂ O ₃ film and the SnO ₂ film decreased and the transmittance increased, as in the case of irradiation during film formation.

In ₂ O ₃ by such Xe particle beam irradiation
The lower resistance and the improved transparency of the film and the SnO ₂ film are considered to be due to the improved crystallinity.

[Embodiment 6] This embodiment is a liquid crystal panel using a transparent conductive film (especially, Examples 1 to 3) produced by the method of the present invention as a transparent electrode. A perspective view of the simple matrix liquid crystal display panel of this embodiment is shown in FIG.

The simple matrix display liquid crystal panel includes an upper glass substrate 14, an upper transparent electrode 12 patterned in stripes, a liquid crystal 15, a lower transparent electrode 13 patterned in a direction intersecting with the upper transparent electrode 12, and a lower portion. It is composed of a glass substrate 16.

Each intersection area of the upper transparent electrode 12 and the lower transparent electrode 13 constitutes a pixel. When a voltage is applied between the upper transparent electrode 12 and the lower transparent electrode 13,
In the pixel area to which the voltage is applied, the orientation of the liquid crystal 15 changes and the light transmittance (or reflectance) is changed.
Changes. By controlling the voltage application and controlling the light transmittance of each pixel, an image can be displayed on the entire screen.

Transparent electrode 1 using the transparent conductive film of the present invention
By forming Nos. 2 and 13, since the transparency is high, it is possible to reduce the loss of light emitted by the backlight. Further, since the resistance is small, it is possible to supply sufficient electric power even if the electrode 12 is thin.

Although the simple matrix is described here, the transparent conductive film of the present invention can be applied to an active matrix liquid crystal display panel. The active matrix is a type in which a thin film transistor (TFT) or a thin film diode is formed in each pixel portion and the voltage applied to the liquid crystal 15 is controlled by these.

[Embodiment 7] This embodiment is an example of a solar cell using the transparent conductive film formed by the method of Embodiments 1 to 3 as an electrode. FIG. 9 is a perspective view of the solar cell of this example.
It was shown to.

The solar cell comprises a positive transparent electrode 17, a P-type Si film 18, an n-type Si film 19 and a negative electrode 20. Sunlight 21 penetrates through the transparent electrode 17 and the P-type Si film 18, n
An electric current is induced in the portion of the type Si film 19. Then, this current is taken out through the positive transparent electrode 17 and the negative electrode 20.

The loss of sunlight 21 can be reduced by forming the transparent electrode 17 by the method of the present invention. Further, it is possible to reduce the loss when the generated electric power is taken out to the outside.

As described above, the transparent conductive film is irradiated with a particle beam made of at least one element of He, Ne, Ar, Kr, and Xe during or after the preparation of the transparent conductive film. By modifying the crystalline state of the film, a transparent conductive film having low resistance and high light transmittance can be obtained. in this case,
The crystallinity can be further enhanced by adjusting the energy of the particle beam to be irradiated according to the crystallization temperature and the film temperature.

By using such a transparent conductive film as an electrode, a liquid crystal display device with high definition and low power consumption or a solar cell with high electromotive force can be obtained.

The transparent conductive film according to the manufacturing method of the present invention is not limited to the above-mentioned embodiments.

[0088]

As described above, according to the present invention, a film having a desired crystal state can be produced. Further, the crystalline state of the film can be modified to a desired state. If this is applied to the production of a transparent conductive film, a transparent conductive film having excellent characteristics of low resistance and high transmittance can be obtained.

Further, by using the transparent conductive film having low resistance and high transmittance thus obtained as an electrode, a display device having high definition and low power consumption or a solar cell having high electromotive force can be prepared.

[Brief description of drawings]

FIG. 1 is a schematic view of a sputtering apparatus for producing a transparent conductive film according to an example of the present invention.

FIG. 2 (a) is an ITO film formed without being irradiated with a particle beam.
The SEM photograph image of the film, (b) is the SEM photograph image of the ITO film formed while irradiating the particle beam.

FIG. 3 (a) is an ITO film formed without being irradiated with a particle beam.
The X-ray diffraction pattern of the film, (b) is the X-ray diffraction pattern of the ITO film formed while irradiating the particle beam, and (c) is the X-ray diffraction pattern of the ITO film formed while irradiating the particle beam. .

FIG. 4 is a graph showing the difference between the specific resistance of the ITO film and the substrate temperature depending on the presence or absence of particle beam irradiation.

FIG. 5 is a graph showing the difference in light transmittance of the ITO film depending on the presence or absence of particle beam irradiation.

FIG. 6 is a graph showing the difference between the specific resistance of the In ₂ O ₃ film and the substrate temperature depending on the presence or absence of particle beam irradiation.

FIG. 7 is a graph showing the difference between the specific resistance of the SnO ₂ film and the substrate temperature depending on the presence or absence of particle beam irradiation.

FIG. 8 is a conceptual diagram showing the structure of a liquid crystal panel using a transparent conductive film produced by the film production method of the present invention as a transparent electrode.

FIG. 9 is a conceptual diagram showing the structure of a solar cell using the transparent conductive film produced by the film production method of the present invention as a transparent electrode.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Vacuum tank, 2 ... Irradiation particle beam generation part, 3 ... Sputtering particle beam generation part, 4 ... Substrate holder, 5 ... Sputter target holder, 6 ... Atmosphere gas introduction pipe, 7 ... Vacuum pump, 8 ... Substrate, 9 ... Sputter target, 10 ...
Sputtered particle beam, 11 ... Irradiated particle beam, 12 ... Upper transparent electrode, 13 ... Lower transparent electrode, 14 ... Upper glass substrate, 15 ... Liquid crystal, 16 ... Lower glass substrate, 17 ...
Positive transparent electrode, 18 ... P-type Si film, 19 ... N-type Si
Membrane, 20 ... Negative electrode, 21 ... Sunlight.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenji Sato, Inventor Kenichi Sato, 1-1, Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd. (72) Inventor, Mitsuhiro Kamei 1-1, Kokubun-cho, Hitachi-shi, Ibaraki No. 1 inside the Kokubun Plant of Hitachi, Ltd.

Claims (10)

[Claims] 1. In the method for producing a film, the film is a tin-added indium oxide film, an indium oxide film, or a tin oxide film, and the He film is formed on the film while forming the film in an atmosphere containing oxygen gas. And a particle beam made of at least one element of Ne, Ar, Kr, and Xe is irradiated. 2. The method for producing a film according to claim 1, wherein the film formation is performed by sputtering. 3. A method for producing a film, which is determined on the basis of a difference between a crystallization temperature of the film and a temperature of the film being formed while the film is being formed. Irradiating a particle beam made of at least one element of He, Ne, Ar, Kr, and Xe with the irradiation energy used for forming the film. 4. When the temperature of the film during the film formation is lower than the crystallization temperature, the irradiation becomes higher as the difference between the crystallization temperature and the temperature of the film during the film formation becomes larger. Enlarging energy, The manufacturing method of the film of Claim 3 characterized by the above-mentioned. 5. The method for producing a film according to claim 1, wherein the particle beam includes at least one of a neutral particle beam and a charged particle beam. 6. A method for modifying a film, which comprises irradiating the film with a particle beam composed of at least one element of He, Ne, Ar, Kr, and Xe. 7. The film is a tin-added indium oxide film, an indium oxide film, or a tin oxide film, and the irradiation of the particle beam is performed in an atmosphere containing oxygen gas. Method of reforming the film. 8. The irradiation energy of the particle beam is determined based on a difference between a crystallization temperature of the film and a temperature of the film at the time of the particle beam irradiation. Method of reforming the film. 9. When the temperature of the film being formed is lower than the crystallization temperature, the irradiation is performed as the difference between the crystallization temperature and the temperature of the film being formed is larger. The method of modifying a film according to claim 6, wherein the energy is increased. 10. The method for modifying a film according to claim 6, wherein the particle beam includes at least one of a neutral particle beam and a charged particle beam.