JP2002237215A - Surface modified transparent conductive film, its surface treatment, and charge injection type light emitting device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface modified transparent conductive film and its surface treatment increasing the work function of transparent conductive film without causing an increase in the surface resistance by modifying physical and electrical properties in the surface area of a transparent conductive film (particularly an ITO film) provided by a sputtering method or the like. SOLUTION: Surface modification is applied by using an electron beam excited plasma and irradiating an ITO film with oxygen ions or electrons within the energy range of 10-80 eV or positive ions of inert gas within the energy range of 20-100 eV.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface treatment method for an ITO film having a low resistivity and a high work function among transparent conductive films using an electron beam excited plasma. Further, the present invention has a light emitting layer made of a light emitting substance,
The present invention relates to a charge-injection light-emitting device that can directly convert light energy into light energy by recombination of charges injected from electrodes when an electric field is applied. The present invention relates to a charge injection type light emitting device using an ITO film whose surface has been modified by irradiating positive ions with an active gas as an electrode.

[0002]

2. Description of the Related Art With the spread of ITO films (transparent conductive patterns) used for liquid crystal or organic light-emitting devices, demands for higher performance have been increasing. There is a strong demand for higher efficiency of charge injection as an electrode.

Conventionally, in order to form an ITO film on a substrate or the like,
A film forming method by a dry process such as vacuum deposition or stapling is generally performed. However,
ITO obtained by vacuum evaporation or sputtering
Since the crystallinity of the ITO film depends on the substrate temperature and the film forming speed during film formation, it is difficult to greatly improve the physical surface shape (surface roughness) and the work function of the ITO film related to the crystal plane. Therefore, it was impossible to improve the function (charge injection property) as an electrode of an organic light emitting device or the like.

On the other hand, the electroluminescence phenomenon of organic materials is 1963.
And was observed in single crystals of anthracene by Pope et al. (J. Chem. Phys. 38 (196)
3) 2042), followed by Helfinch and Schneid in 1965
er) succeeded in observing a relatively strong injection-type EL (electroluminescence) by using a solution electrode system having high injection efficiency (Phys. Rev. Lett. 14).
(1965) 229).

Since then, US Pat. No. 3,172,862
No. 3,173,050, U.S. Pat.
0,167, J.M. Chem. Phys. 44 (196
6) 2902; Chem. Phys. 50 (196
9) 14364; Chem. Phys. 58 (19
73) 1542, or Chem. Phys. Le
tt. 36 (1975) 345, etc., studies have been conducted on the formation of an organic luminescent material with a conjugated organic host material and a conjugated organic activator having a fused benzene ring. Naphthalene, anthracene, phenanthrene,
Tetracene, pyrene, benzopyrene, chrysene, picene, carbazole, fluorene, biphenyl, terphenyl, triphenylene oxide, dihalobiphenyl,
Trans-stilpen and 1,4-diphenylbutadiene, etc., were given as examples of organic host materials, and anthracene, tetracene, bentacene, etc. were mentioned as examples of activators.

However, all of these organic luminescent substances exist as a single layer having a thickness exceeding 1 μm or more, and a high electric field is required for light emission. For this reason, research on a thin film element by a vacuum deposition method has been advanced (for example, Thin So).
lid Films 94 (1982) 171, Pol
ymer 24 (1983) 748, Jpn. J. Ap
pl. Phys. 25 (1986) L773).

Although thinning has been effective in reducing the driving voltage, it has not been possible to obtain a high-brightness element on a practical level.

Recently, however, Tang et al. (App
l. Phys. Lett. 51 (1987) 913 or U.S. Pat. No. 4,356,429), devising an EL device in which two extremely thin layers (a charge transport layer and a light emitting layer) are stacked by vacuum deposition between an anode and a cathode, and low driving is performed. High brightness was achieved with voltage. This type of stacked organic EL device has been actively studied thereafter, and is disclosed in, for example, JP-A-59-194393.
No. 4,539,507, Japanese Unexamined Patent Publication No.
194393, U.S. Pat. No. 4,720,432,
JP-A-63-264692, Appl. Phys
s. Lett. 55 (1989) 1467;
163188.

Further, Jpn. J. Appl. Phys
s. 27 (1988) L269. L713 reports a three-layered EL device in which the functions of carrier transport and light emission are separated. In selecting a dye of a light emitting layer that determines a light emission color, restrictions on carrier transport performance are relaxed and freedom of selection is increased. It is also suggested that there is a possibility of improving the light emission by effectively confining holes and electrons (or excitons) in the central light emitting layer.

Although a vacuum evaporation method is generally used for producing a stacked organic EL device, it has been reported that a device having a considerably high brightness can be obtained by a casting method (for example, the 50th application). Proceedings of academic conference
006 (1989) and Proceedings of the 51st Academic Lecture Meeting of the Japan Society for Response Science 1041 (1990)).

Furthermore, even a mixed single-layer EL device formed by a dip coating method from a solution in which polyvinyl carbazole as a hole transport compound, an oxadiazole derivative as an electron transport compound, and coumarin 6 as a luminescent material has a considerably high luminous efficiency. Has been reported (eg,
Proceedings of the 38th Annual Conference of the Famous Relationships of the Lectures 1086 (19
91)).

As mentioned above, recent advances in organic EL devices have suggested a remarkably wide range of possible applications.

[0013] However, the history of such research is still young, and the research on the material and the device development has not yet been sufficiently performed. At present, there is still a problem in terms of durability, such as light output with even higher luminance, a change with time due to long-term use, and deterioration due to an atmospheric gas containing oxygen or moisture.

[0014]

SUMMARY OF THE INVENTION The present invention has been made to solve such problems of the prior art.
Modified the physical and electrical properties of the transparent conductive film (especially ITO film) obtained by sputtering or the like in the surface region, and increased the work function of the transparent conductive film without causing an increase in sheet resistance. Surface-modified transparent conductive film,
It is another object of the present invention to provide this surface treatment method.

Further, the present invention uses a surface-modified ITO film obtained as described above as an electrode of a charge injection type light emitting element, thereby providing a charge injection type light emitting element having a light output with a higher brightness than ever before. The purpose is to provide.

[0016]

That is, the surface-modified transparent conductive film of the present invention is characterized in that the surface of the transparent conductive film has been subjected to surface modification using electron beam excited plasma. It is characterized in that an ITO film is used as the conductive film.

The surface-modified transparent conductive film of the present invention has a further preferable feature that "the surface of the ITO film is irradiated with oxygen ions or electrons having an energy range of 10 to 80 eV using an electron beam excited plasma. That the reforming has been performed "and" 20-100
Irradiation of the ITO film with positive ions by an inert gas having an energy range of eV to perform surface modification ”,“ Positive ions by an inert gas having an energy range of 20 to 100 eV using an electron beam excited plasma ” After irradiating the ITO film with oxygen ions or electrons having an energy range of 10 to 80 eV to irradiate the ITO film to modify the surface area. " Quality "and" work function is 5.2 eV
Above. "

Further, the surface treatment method for a surface-modified transparent conductive film of the present invention is characterized in that the surface of the transparent conductive film is modified by using electron beam excited plasma. Is characterized by using an ITO film.

The surface treatment method for a surface-modified transparent conductive film according to the present invention has a further preferable feature that "oxygen ions or electrons having an energy range of 10 to 80 eV are applied to the ITO film using an electron beam excited plasma. Irradiation and surface modification ". In this case," the oxygen ions have a power of at least 1 mW / cm ² or more and 1 W / cm ² or less, and the electrons have a power of at least 0.1 W / cm ² or more and 10 W / cm ² or less. "Improving the surface of the ITO film by irradiating the ITO film with positive ions of an inert gas having an energy range of 20 to 100 eV using an electron beam excited plasma", Power of at least 10 mW / cm ^{2 to} 1 W / cm ² by ITO
Irradiating the ITO film with positive ions of an inert gas in an energy range of 20 to 100 eV using an electron beam excited plasma, and then applying 10 to 80
oxygen ions or electrons in the energy range of eV to IT
Irradiating the O film to modify the surface ”and“ Modifying the surface region of the ITO film within 5 nm in the depth direction ”.

Further, the charge injection type light emitting device of the present invention is characterized in that a surface modified ITO film subjected to surface modification using electron beam excited plasma is used as an electrode.

The charge injection type light emitting device of the present invention has a further preferable feature that "the surface-modified ITO film is formed by using an electron beam-excited plasma to convert oxygen ions or electrons having an energy range of 10 to 80 eV into ITO. That the surface is modified by irradiating the film ”and“ the surface-modified ITO film is 20 to 1
Irradiation of positive ions by an inert gas in the energy range of 00 eV to the ITO film to perform surface modification ”,“ The surface modified ITO film is 20 to 100 eV using electron beam excited plasma. After irradiating the ITO film with positive ions due to the inert gas in the energy range of
Irradiation of oxygen ions or electrons in the energy range of 10 to 80 eV to the ITO film to perform surface modification ”,“ The surface modified ITO film has a surface within 5 nm in the depth direction of the ITO film. The area must be modified. "
"The work function of the surface-modified ITO film is 5.2 eV or more", and "an organic film having an ionization potential of 5.2 eV or more is formed on the surface-modified ITO film". .

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The surface-modified transparent conductive film of the present invention is obtained by subjecting an ITO film to a surface treatment, and using an electron beam excited plasma as the surface treatment method. Alternatively, surface modification is performed by irradiating electrons or positive ions by an inert gas to the ITO film.

In general, I prepared by a sputtering method or the like
The total thickness of the TO film is as thin as 100 to 200 nm in order to achieve both sheet resistance and light transmittance, and unevenness of several nm to several tens nm is present on the surface due to the influence of crystallization during film formation.

After the ITO film is formed, the surface region of the ITO film is contaminated with dust and hydrocarbon-based deposits by leaving it in the air or washing with an organic solvent.

Further, in such an ITO film, since the crystallinity of the ITO depends on the substrate temperature and the film forming rate at the time of film forming, the
The work function of the TO film was fixed at about 4.5 eV, and it was impossible to greatly improve the work function value.

On the other hand, in the present invention, specifically, for example, a beam in which the energy of oxygen ions or electrons is 10 to 80 eV, preferably 20 to 60 eV is used, and in the case of oxygen ions, at least 1 mW / cm ^{2 to} 1 W / cm ² With the power of
In the case of electrons, at least 0.1 W / cm ^{2 to} 10 W
By irradiating a surface region within 5 nm in the depth direction of the ITO film with a power of / cm ² , the work function can be increased without causing an increase in the sheet resistance of the ITO film, and an organic light emitting device or the like It has become possible to improve the function (charge injection property) of the charge injection type light emitting element as an anode.

The work function of the thus obtained surface-modified ITO film of the present invention can be increased to 5.2 eV or more.

As described above, since the work function of the surface-modified ITO film of the present invention is increased, a charge injection type light-emitting device (organic light-emitting device) using this surface-modified ITO film as an electrode is used to form the surface. It is necessary to take into account the energy matching of charge injection with the ionization potential of the organic film formed on the modified ITO film.

That is, by making the work function of the surface-modified ITO film close to the value of the ionization potential of the organic film to be formed on the ITO, it is possible to maintain the optimal charge injection between the two. Therefore, the surface modification I
The ionization potential of the organic film formed on the TO is 5.
It is preferably 2 eV or more.

Further, in the surface treatment method of the present invention, the energy of the positive ions due to the inert gas is 20 to 100 eV,
The particles, which are preferably between 30 and 60 eV, are
Irradiation with a power of 0 mW / cm ^{2 to 1} W / cm ² , particularly preferably to a surface region within 5 nm in the depth direction of the ITO film, removes dirt on the surface region without causing an increase in sheet resistance of the ITO film. Removed and additionally function as anode of charge injection type light emitting device (organic light emitting device) (charge injection property)
Can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a surface treatment apparatus using an electron beam excited plasma as an example for performing the method for treating the surface of an ITO film according to the present invention. The characteristics of the electron beam excited plasma are that high-density plasma can be generated at a low gas pressure (about several hundred mPa) and that ion energy, ion current, and the like can be easily controlled by using an external power supply.

The above-mentioned surface treatment apparatus comprises a discharge plasma region,
It is composed of three parts: an electron acceleration region and a plasma processing region in which plasma is generated by an electron beam. Then, ITO for performing surface treatment on the plasma treatment region
A substrate holder 1 for holding a substrate having a film (ITO substrate) is connected to an ammeter 2 and a DC power supply 3.

Next, the procedure of plasma generation will be described below.
The LaB ₆ filament 4 in the discharge plasma region is electrically heated by using the heating power supply 5 to emit sufficient thermoelectrons from the filament, and then Ar gas is introduced into the discharge plasma region via a mass flow controller (not shown). Next, using the discharge power source 6, plasma is generated in the discharge plasma region. Further, electrons are extracted from the plasma generated in the discharge plasma region by using the acceleration power supply 7, and the electrons are accelerated in the electron acceleration region. Next, the accelerated electron beam enters the plasma processing region and collides with the introduced gas molecules (oxygen or inert gas) to generate high-density plasma.
Further, this processing apparatus uses a coil 8 to control 300 to 600 G in order to suppress diffusion of an electron beam or plasma to a wall.
Is applied in the axial direction, and the diameter of the plasma can be controlled by changing the intensity of the axial magnetic field. When an arbitrary voltage is applied to the substrate holder 1 using the DC power supply 2 in such a state, charged particles (oxygen ions or electrons and positive ions due to an inert gas) in the plasma are extracted, and I attached
The surface of the TO substrate is irradiated with charged particles, and the surface of the ITO film is modified.

The reason why the voltage applied to the substrate holder and the energy of the charged particles are synonymous is that the kinetic energy of the charged particles accelerated by the applied voltage is substantially equal to the applied voltage. Things.

In the surface treatment method for an ITO film according to the present invention, the plasma density to be generated is preferably 10 ⁹ to 10 ⁹ .
10 ¹³ cm ^-3 , more preferably 10 ¹⁰ to 10 ¹² cm ^-3
It is desirable that the irradiation distance be within the range described above, since irradiation can be performed without damaging the ITO film.

Next, an organic light emitting device will be described in more detail with reference to the drawings as a specific example of the charge injection type light emitting device of the present invention.

FIG. 2 is a sectional view showing an example of the organic light emitting device of the present invention. FIG. 2 shows an anode 10 and a light emitting layer 1 on a substrate 9.
1 and a cathode 12 are sequentially provided. The light emitting layer 11 used here is useful when it has a single hole transporting ability, electron transporting ability and light emitting performance by itself, or when it is used by mixing compounds having the respective properties.

FIG. 3 is a sectional view showing another example of the organic light emitting device of the present invention. FIG. 3 shows a structure in which an anode 10, a hole transport layer 13, an electron transport layer 14, and a cathode 12 are sequentially provided on a substrate 9. In this case, the luminescent material has a hole transporting property or an electron transporting property, or a material having both functions, in each layer, and is combined with a simple hole transporting substance having no luminescent property or an electron transporting substance. Useful when used. In this case, the light emitting layer 11 includes the hole transport layer 13 and the electron transport layer 14.

FIG. 4 is a sectional view showing another example of the organic light emitting device of the present invention. FIG. 4 shows an anode 10, a hole transport layer 13, a light emitting layer 11, an electron transport layer 14 and a cathode 12 on a substrate 9.
Are sequentially provided.

FIG. 5 is a sectional view showing another example of the organic light emitting device of the present invention. FIG. 5 shows a structure in which an anode 10, a light emitting layer 11, an electron transport layer 14, and a cathode 12 are sequentially provided on a substrate 9.

The organic light-emitting devices shown in FIGS. 4 and 5 separate the functions of carrier transport and light emission.
It is used in combination with a compound having hole transporting, electron transporting, and light emitting properties in a timely manner, so that the degree of freedom of material selection is greatly increased and various compounds having different emission wavelengths can be used. Hue can be diversified. In addition, it becomes possible to effectively confine holes and electrons (or excitons) in the central light emitting layer to improve the light emission efficiency.

The organic light-emitting device according to the present invention is extremely excellent in hole injection and electron injection properties as compared with the conventional organic light-emitting device, and may be configured as shown in any of FIGS. Is possible.

In general, an organic light emitting device is a charge injection type light emitting device, and emits light strongly depending on the amount of carriers (holes or electrons) injected from an electrode. It is desirable that the carrier injection from the electrodes (anode and cathode) is always constant even when used for a long time.

However, an ITO electrode usually used as an actual anode has incomplete electrical and physical matching as an electrode, such as a physical surface shape, a contamination of a surface region, and a work function due to the film forming method. Combined with this, the current flowing through the device (due to carrier injection from the electrodes) was reduced, resulting in a significant decrease in light output.

However, the organic light-emitting device using the surface-modified ITO film subjected to the surface treatment method of the present invention as an anode is in such a state that the electronic matching between the electrode and the layer made of the organic compound in contact therewith is optimal. For this reason, the carrier injection amount from the anode was increased, and the light emission luminance was dramatically improved.

The transparent conductive film used in the surface treatment method of the present invention is not limited to the ITO film as long as it is transparent and conductive. For example, SnO ₂ , ZnO, MgIn ₂ O ₄ , Zn ₂ I
n ₂ O ₅ , InGaZnO ₄ or the like can also be used.

In the organic light-emitting device of the present invention, as a light-emitting layer constituent component, a hole-transporting compound which has been studied in the field of electrophotographic photoreceptors, a known hole-transporting light-emitting compound or an electron-transporting compound. If necessary, two or more kinds of compounds and electron transporting luminescent compounds known so far can be used.

In the organic light-emitting device of the present invention, the light-emitting layer can be generally formed into a thin film by vacuum evaporation or a combination with an appropriate binder resin.

The binder can be selected from a wide range of binder resins, for example, polyvinyl carbazole resin, polycarbonate resin, polyester resin, polyarylate resin, butyral resin, polystyrene resin, polyvinyl acetal resin, diallyl phthalate resin, acrylic resin Resin, methacrylic resin, phenolic resin, epoxy resin,
Examples include, but are not limited to, silicone resins, polysulfone resins, urea resins, and the like. These may be used alone or as a copolymer in one kind or as a mixture of two or more kinds.

On the other hand, as the cathode material, lithium, calcium, magnesium, silver, lead, tin, magnesium, aluminum, manganese, indium, chromium, or an alloy thereof having a small work function is used.

The organic light emitting device of the present invention comprises a conventional incandescent lamp,
Unlike fluorescent lamps or light emitting diodes, large areas,
It is a high-resolution, thin, light-weight, high-speed, fully solid-state device that can be used for EL panels that may meet advanced requirements.

[0053]

The present invention will be described below in detail with reference to examples.

(Examples 1 to 8 and Comparative Example 1) An ITO substrate having a 110 nm-thick ITO film formed on a glass substrate by an ion plating method is held in a substrate holder of the surface treatment apparatus shown in FIG. did.

Next, the interior of a chamber of a surface treatment apparatus equipped with an electron beam excited plasma irradiation apparatus (manufactured by Nichimen Electronics Co., Ltd.) was about 1.3 × 10 ⁻⁴ Pa (1 × 10 ⁻⁶ To).
After evacuating to rr), oxygen gas is flowed through the mass flow controller at a flow rate of 20 ccm, and the pressure in the plasma processing is about 2.7 × 10 ^-1 Pa (2 × 10 ^-3 To
rr).

Then, the acceleration voltage was set to 70 V, oxygen plasma was generated in the plasma processing, and a voltage of -10 V (corresponding to an energy of 10 eV) was applied to the substrate holder for 30 seconds to form an ITO film. Surface treatment was performed.

Immediately after the processing, the following structural formula (1)
A hole transporting layer (film thickness 50n)
m), and a light-emitting layer (thickness: 50 nm) made of an aluminum quinolinol complex (Alq ₃ ), and a cathode (thickness: 200 nm) made of Al are formed by vacuum evaporation in this order.
The device of Example 1 was produced.

[0058]

Embedded image

The voltage applied to the substrate holder is-
5, -20V, -40V, -60V, -80, -85V
An element manufactured in the same manner as in Example 1 except that
The devices were Examples 2 to 7, respectively.

Further, the voltage applied to the substrate holder is -4
A hole transport layer (film thickness: 50 nm) made of a compound represented by the following structural formula (2) on ITO treated at 0 V
An element manufactured in the same manner as in Example 1 except that was formed is referred to as an element of Example 8.

[0061]

Embedded image

On the other hand, an element prepared in the same manner as in Example 1 except that no treatment was performed was used as an element of Comparative Example 1.

Table 1 shows the results of measuring the light emission luminance by applying a voltage of 12 V to the device thus manufactured. The change in the work function of the ITO film due to the plasma treatment was measured using a Fermi level measuring device (manufactured by Riken Keiki Co., FAC-1), and the ionization potential of the hole transport layer formed on the ITO film was low. The measurement was performed using an energy electron spectrometer (AC-1 manufactured by Riken Keiki Co., Ltd.).

[0064]

[Table 1]

As is clear from the results shown in Table 1, ITO
Light-Emitting Element Using Surface-Modified ITO Treated to Have a Film Work Function of 5.2 eV or More (Example 1)
It can be seen that the light emission luminances of (8) to (8) are improved on a flight day basis. In addition, the larger the ionization potential of the hole transport layer formed on the surface-modified ITO, the more effective.

(Examples 9 to 15 and Comparative Example 2) A 120 nm-thick IT was formed on a glass substrate by sputtering.
The ITO substrate on which the O film was formed was held in the substrate holder of the surface treatment apparatus shown in FIG.

Next, the inside of the chamber of the surface treatment apparatus equipped with the electron beam excited plasma irradiation apparatus (manufactured by Nichimen Electronics Co., Ltd.) was about 1.3 × 10 ^-4 Pa (1 × 10 ^-6 To).
After evacuating to rr), argon gas was flowed at a flow rate of 50 ccm through the mass flow controller, and the pressure in the plasma processing was set to about 4 × 10 ⁻¹ Pa (3 × 10 ⁻³ Torr).
r).

Next, the acceleration voltage was set to 100 V,
After generating argon plasma in the plasma processing, a surface treatment of the ITO film was performed by applying a voltage of −20 V (corresponding to an energy of 20 eV) to the substrate holder for 15 seconds.

Immediately after the processing, the following structural formula (3)
(A film thickness of 50 n)
m), and a light-emitting layer made of Alq ₃ (film thickness 50 n
m), and a cathode (thickness: 200 nm) made of Al was further formed by vacuum evaporation in each order to produce a device of Example 9.

[0070]

Embedded image

The voltage applied to the substrate holder is -1.
The devices manufactured in the same manner as in Example 9 except that they were 5, -30 V, -60 V, -100, and -110 V were used as devices of Examples 10 to 14, respectively.

Further, the voltage applied to the substrate holder is -6.
A device fabricated in the same manner as in the ninth embodiment except that the ITO substrate treated at 0 V was subsequently subjected to the oxygen plasma treatment under the same conditions as in the fifth embodiment is referred to as a device of the fifteenth embodiment.

On the other hand, an element prepared in the same manner as in Example 9 except that no treatment was performed was used as an element of Comparative Example 2.

Table 2 shows the results of measuring the light emission luminance by applying a voltage of 13 V to the device thus manufactured.

[0075]

[Table 2]

As is clear from the results shown in Table 2, the light-emitting elements (Examples 9 to 14) using the surface-modified ITO subjected to the surface treatment with the argon ion energy in the range of 20 to 100 eV as the electrode were used. It can be seen that the light emission luminance is greatly improved. Further, the luminous brightness of the light emitting device (Example 15) having the surface-modified ITO electrode which was treated with argon ions and then treated with oxygen ions was further drastically improved.

[0077]

As described above, when the surface treatment method of the present invention is applied to a transparent conductive film (particularly, an ITO film), the work function of the ITO film can be increased without increasing the sheet resistance. .

Further, by using the surface-modified transparent conductive film (particularly, ITO film) thus surface-modified as an anode of a charge injection type light-emitting device (organic light-emitting device), extremely high emission luminance can be obtained. The device was obtained.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of a surface treatment apparatus for performing a method of surface treating an ITO film according to the present invention.

FIG. 2 is a sectional view showing an example of the organic light emitting device of the present invention.

FIG. 3 is a sectional view showing another example of the organic light emitting device of the present invention.

FIG. 4 is a sectional view showing another example of the organic light emitting device of the present invention.

FIG. 5 is a sectional view showing another example of the organic light emitting device of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Substrate holder 2 Ammeter 3 DC power supply 4 LaB ₆ Filament 5 Heating power supply 6 Discharge power supply 7 Acceleration power supply 8 Coil 9 Substrate 10 Anode 11 Light emitting layer 12 Cathode 13 Hole transport layer 14 Electron transport layer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazunori Ueno 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Tsuyoshi Sakakibara 6-27-2 Sagimiya, Nakano-ku, Tokyo F-term ( Reference) 3K007 AB02 AB05 CB01 DA02 EB00 FA01 5G307 FA01 FB01 FC02 FC10 5G323 BC03

Claims (22)

[Claims] 1. A surface-modified transparent conductive film obtained by modifying the surface of a transparent conductive film using electron beam excited plasma. 2. The surface-modified transparent conductive film according to claim 1, wherein an ITO film is used as the transparent conductive film. 3. The method using an electron beam excited plasma.
The surface-modified transparent conductive film according to claim 2, wherein the surface modification is performed by irradiating oxygen ions or electrons having an energy range of 80 eV to the ITO film. 4. Use of an electron beam excited plasma for 20 to
3. The surface-modified transparent conductive film according to claim 2, wherein a surface modification is performed by irradiating the ITO film with positive ions by an inert gas having an energy range of 100 eV. 5. An electron beam-excited plasma for 20 to
After irradiating the ITO film with positive ions by an inert gas having an energy range of 100 eV, the ITO film is irradiated with oxygen ions or electrons having an energy range of 10 to 80 eV to perform surface modification. The surface-modified transparent conductive film according to claim 2. 6. The surface-modified transparent conductive film according to claim 2, wherein a surface region of the ITO film within 5 nm in a depth direction is modified. 7. The surface-modified transparent conductive film according to claim 2, which has a work function of 5.2 eV or more. 8. A surface treatment method for a surface-modified transparent conductive film, wherein the surface of the transparent conductive film is modified using electron beam excited plasma. 9. The surface treatment method for a surface-modified transparent conductive film according to claim 8, wherein an ITO film is used as the transparent conductive film. 10. The method according to claim 10, wherein the electron beam excitation plasma is used.
10. The surface treatment method for a surface-modified transparent conductive film according to claim 9, wherein the ITO film is irradiated with oxygen ions or electrons having an energy in the range of -80 eV to perform surface modification. 11. The method according to claim 1, wherein the oxygen ions are at least 1 mW /
cm ² or more and 1 W / cm ² or less, and the electrons are at least 0.1 W / cm ² .
1W / cm ² or more 10 W / cm ² surface treatment method of the surface modification transparent conductive film according to claim 10, the following power, characterized in that applied to the ITO film surface. 12. The method according to claim 12, wherein the electron beam excitation plasma is used.
The surface treatment method for a surface-modified transparent conductive film according to claim 9, wherein the ITO film is irradiated with positive ions by an inert gas having an energy range of １００100 eV to perform surface modification. 13. The method of claim 1, wherein the positive ions are at least 10 mW /
13. The surface treatment method for a surface-modified transparent conductive film according to claim 12, wherein a power of not less than cm ^{2 and not} more than 1 W / cm ^{2 is} applied to the surface of the ITO film. 14. The method as claimed in claim 14, wherein the electron beam excited plasma is used.
After the ITO film is irradiated with positive ions by an inert gas having an energy range of １００100 eV, the ITO film is irradiated with oxygen ions or electrons having an energy range of 10 to 80 eV to perform surface modification. A surface treatment method for a surface-modified transparent conductive film according to claim 9. 15. The surface treatment method for a surface-modified transparent conductive film according to claim 9, wherein the surface region of the ITO film within 5 nm in a depth direction is modified. 16. A charge-injection light-emitting device using a surface-modified ITO film whose surface has been modified by using electron beam excited plasma as an electrode. 17. The surface-modified ITO film has been subjected to surface modification by irradiating oxygen ions or electrons having an energy range of 10 to 80 eV to the ITO film using an electron beam excited plasma. The charge injection type light emitting device according to claim 16, characterized in that: 18. The surface-modified ITO film has been subjected to surface modification by irradiating the ITO film with positive ions of an inert gas having an energy range of 20 to 100 eV using electron beam excited plasma. The charge injection type light emitting device according to claim 16, wherein: 19. The surface-modified ITO film has an energy range of 10 to 80 eV after irradiating the ITO film with positive ions by an inert gas having an energy range of 20 to 100 eV using an electron beam excited plasma. 17. The charge injection type light emitting device according to claim 16, wherein the ITO film is irradiated with oxygen ions or electrons to perform surface modification. 20. The charge injection type according to claim 16, wherein the surface-modified ITO film is obtained by modifying a surface region of the ITO film within a depth direction of 5 nm. Light emitting element. 21. The charge injection type light emitting device according to claim 16, wherein the surface modified ITO film has a work function of 5.2 eV or more. 22. The charge injection type light emitting device according to claim 21, wherein an organic film having an ionization potential of 5.2 eV or more is formed on the surface modified ITO film.