JPH09302470A - Forming method of conductive film, and forming method of metallic oxide film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive film forming method capable of forming the conductive film of low resistance, and a metallic oxide film forming method capable of forming the metallic oxide film such as a ferroelectric thin film of high residual polarizability and a ferroelectric thin film of low coercive force. SOLUTION: The resistivity of a conductive film is dropped by irradiating the light of <=400nm in wavelength on the conductive film formed on a substrate so as not to generate crystallization of the conductive film. The characteristics of the metallic thin film such as increase of the residual polarizability and reduction of the coercive force are changed by irradiating the light of <=400nm in wavelength so as not to generate crystallization in the metallic oxide film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a conductive film having a low resistivity and a method of forming a metal oxide film such as a ferroelectric thin film having a high remanent polarizability and a ferromagnetic thin film having a low coercive force.

[0002]

2. Description of the Related Art Conventionally, conductive films and transparent conductive films have been used in various electronic parts, image display devices, etc.
The transparent conductive film is formed by using indium tin oxide (ITO), zinc oxide (ZnO), tin oxide (SnO ₂ ), or the like, or an alloy thereof by a film forming method such as a sputtering method, a vacuum evaporation method, or a CVD method. Was there.

Among the above film forming methods, the sputtering method is a method of forming an ITO film on a substrate by sputtering an ITO oxide target material with Ar ions. Such an ITO film has a substrate temperature of 200 to 300 ° C.
After forming the film in 1., an annealing treatment was performed at 200 to 300 ° C. to reduce the resistance.

However, as the demand for forming a conductive film on a substrate having low heat resistance in electronic parts, image display devices, etc. increases, formation of a low resistance conductive film at a low temperature of room temperature to 200 ° C. becomes an important issue. Has become. Usually, an IT formed by a sputtering method at a substrate temperature of 200 ° C. or lower at a low temperature.
Since the O film has a high resistivity, it is difficult to use it as it is for various electronic parts, image display devices and the like. For this reason,
It is necessary to reduce the resistance by performing an annealing treatment on the ITO film formed at a low temperature by the sputtering method.

On the other hand, a ferroelectric thin film made of a metal oxide film is expected to be applied to a pyroelectric sensor, a non-volatile memory, etc., and a strong residual polarizability is expected for practical use in such a device. Formation of a dielectric thin film is required.

The ferromagnetic thin film made of a metal oxide film is
Applications for thin-film magnetic head materials and recording materials have been developed. As a method of forming this ferromagnetic thin film,
Generally, the vapor deposition method, the sputtering method, the coating method and the like are known, and a ferromagnetic thin film having practically sufficient characteristics has been obtained. However, there is a demand for improving the recording density characteristic of the ferromagnetic thin film as an information recording material. , It is getting tougher year by year.

[0007]

The annealing treatment after the film formation at a low temperature in the above-described conductive film formation cannot be performed at a high temperature in order to protect a substrate having low heat resistance, and therefore a sufficiently low temperature is required. There was a problem that resistance could not be achieved. In addition, the substrate temperature is 200 to 30 on the substrate having high heat resistance.
Even for a conductive film formed at 0 ° C., the above-mentioned annealing treatment reduces the resistance of the entire surface of the ITO film, and the resistance can be reduced without changing the crystallinity of only a desired region or pattern. Is desired.

Further, in order to form the above-mentioned ferroelectric thin film having a high residual polarizability, strict control of film forming conditions is required, and a fatigue phenomenon which has recently become a problem (in a repeated polarization reversal test) It is also necessary to deal with (change in residual polarizability), and it is necessary to perform treatment for increasing the residual polarizability on the ferroelectric thin film after film formation. However, in reality, there is no effective treatment method other than the annealing treatment after the film formation.

Furthermore, in order to improve the recording density characteristics of the above-mentioned ferromagnetic thin film, it is important to reduce the coercive force, which is a magnetic characteristic, and to reduce the crystal grain boundaries in the magnetic material that cause coercive force. Therefore, it is necessary to manufacture a ferromagnetic thin film whose domain wall can be easily moved in a low magnetic field. However, in order to form such a ferromagnetic thin film, strict control of film forming conditions is required. Therefore, there is a demand for a method capable of easily forming a ferromagnetic thin film having a low coercive force.

The present invention has been made in view of the above circumstances, and it is a method of forming a conductive film having a low resistance, and a ferroelectric thin film having a high residual polarizability and a low dielectric constant. An object of the present invention is to provide a method for forming a metal oxide film, which can form a metal oxide film such as a ferromagnetic thin film having a coercive force.

[0011]

In order to achieve such an object, the method for forming a conductive film according to the present invention is such that, after the conductive film is formed on a substrate, the conductive film is not crystallized. It was configured to irradiate light having a wavelength of 400 nm or less with irradiation energy.

Further, the method of forming a conductive film of the present invention is configured such that the substrate temperature during the formation of the conductive film is set in the range of room temperature to 200 ° C.

The conductive film forming method of the present invention includes a sputtering method, a vacuum deposition method, an ion plating method,
The conductive film was formed by any one of the CVD methods.

In the method for forming a metal oxide film of the present invention, after the metal oxide film is formed on the substrate, the metal oxide film is irradiated with light having a wavelength of 400 nm or less with irradiation energy in a range that does not cause crystallization of the metal oxide film. It was configured.

The method of forming a metal oxide film of the present invention is
The metal oxide film is formed by any one of the sputtering method, the vacuum deposition method, the ion plating method, and the CVD method.

In the present invention as described above, the light having a wavelength of 400 nm or less, which is irradiated so as not to cause crystallization of the conductive film formed on the substrate, has the function of increasing the density of conduction electrons in the conductive film. None, the conductivity of the conductive film is improved (low resistance).

The metal oxide film formed on the substrate is irradiated with a wavelength of 400 n so as not to cause its crystallization.
The light having a wavelength of m or less has an effect of increasing the remanent polarizability when the metal oxide film is a ferroelectric thin film, and the crystal in the metal oxide film when the metal oxide film is a ferromagnetic thin film. It acts to extinguish grain boundaries.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. Method for forming conductive film The method for forming a conductive film of the present invention is to irradiate a conductive film formed on a substrate with light having a wavelength of 400 nm or less with an irradiation energy amount that does not cause crystallization of the conductive film. The density of conduction electrons in the conductive film is increased to reduce the resistivity.

The conductive film in the present invention can be formed by any one of the conventionally known methods such as a sputtering method, a vacuum deposition method, an ion plating method and a CVD method.

For example, when the conductive film is formed by the sputtering method, first, a desired target material is attached to the target material attachment plate in the vacuum chamber, and the substrate is attached on the substrate holder. The target material mounting plate can be applied with a voltage from an external power source, and the substrate holder is arranged at a position facing the target material mounting plate. The substrate holder may be provided with heating means for heating the placed substrate to a predetermined temperature. Next, after the pressure inside the vacuum chamber was reduced to a predetermined pressure by the exhaust pipe, argon (Ar) was supplied from the gas supply pipe.
An atmospheric gas such as gas is supplied into the vacuum chamber until the pressure reaches a predetermined level. Then, by applying a voltage to the target material from an external power source, the target material is sputtered, and formation of a conductive film is started on the substrate kept at a temperature appropriately set from a room temperature to 350 ° C. temperature range. .

After the conductive film having a desired thickness is formed on the substrate as described above, the conductive film on the substrate has a wavelength of 400 nm.
Hereinafter, it is preferably irradiated with light of 150 to 400 nm.
When the wavelength of the irradiated light exceeds 400 nm, the conduction electron density in the conductive film cannot be increased and the effect of the present invention cannot be obtained. Such irradiation of the light source, ultra-high pressure, high pressure, medium pressure, low pressure metal vapor gas, noble gas, hydrogen, Xe _2, Kr-Cl, light source using a Xe-Cl, for example, a high pressure mercury lamp, Light source such as excimer lamp, excimer laser, dye laser, Ar
A laser such as an ion laser or an F ₂ laser can be used. More specifically, a Hg-Xe ultraviolet lamp (wavelength main peak = 360 nm), a low pressure Hg lamp (wavelength main peak = 254 nm), a Kr-Cl excimer lamp (wavelength main peak = 222 nm), or Xe- Cl (308 nm), Xe-F (351
nm), Xe-Br (282 nm), Kr-F (249
nm), Kr-Cl (222 nm) excimer laser, Ar ion laser second harmonic (257.2n)
m), second harmonic crystal of dye laser (β-BaB ₂ · B
O ₄ , 205 nm), F ₂ laser (157 nm) and the like. By arranging such a light source in the vacuum chamber and irradiating the substrate mounting surface of the substrate holder, it is possible to irradiate the conductive film with light.

The irradiation energy in this light irradiation is a condition that the density of the conduction electrons in the conductive film is increased and the resistivity is lowered without causing crystallization of the conductive film. It can be appropriately set according to the thickness of the film, the light source used, the purpose of use of the conductive film, and the like. Here, not causing crystallization of the conductive film means not causing crystallization of the amorphous conductive film, or maintaining or lowering the crystallinity of the crystalline conductive film. As an example of irradiation energy, when a 1500 Å-thick indium tin oxide (ITO) film formed at room temperature by a sputtering method is irradiated with a Xe-Cl excimer laser, the irradiation energy is about 100 m.
J / cm ² is preferable, and if the irradiation energy is too high, crystallization will proceed and the resistivity will sharply increase.

The conductive film that can be formed by the present invention is, for example, a conductive film made of a metal such as Au, Ag, Pt, Cu, Rh, tin-indium oxide (ITO), zinc oxide (ZnO), tin oxide (SnO). ₂ ), lanthanum titanate (LaTiO ₃ ), indium zinc oxide (In ₂ O ₃
-ZnO), antimony tin oxide (SbSnO)
₂ ), indium oxide (In ₂ O ₃ ), zinc-tin-indium oxide ((Zn, Sn) In ₂ O ₃ ), alumina-zinc oxide (ZnO-Al ₂ O ₃ ), gallium-zinc oxide _{(ZnO-Ga 2 O 3)} , cadmium tin oxide (Cd ₂ SnO _4), cadmium oxide (CdO),
Cadmium / indium oxide (CdIn ₂ O ₄ ), etc.
Also, the conductive film is made of an alloy or the like, and its thickness can be set appropriately. The substrate on which the conductive film is formed is, for example, a glass substrate, a ceramic substrate,
Silicon substrate, polycarbonate resin, polyethylene terephthalate resin, polyester resin, epoxy resin,
A resin substrate such as an acrylic resin or a polystyrene resin, a metal substrate, or the like can be given, and the thickness thereof can be set as appropriate depending on the purpose of use. Method for Forming Metal Oxide Film The method for forming a metal oxide film according to the present invention is a method for forming a metal oxide film formed on a substrate with light having a wavelength of 400 nm or less with an irradiation energy amount that does not cause crystallization of the metal oxide film. By irradiating with, the desired changes are made to the physical properties of the metal oxide film.

The metal oxide film that can be formed by the present invention includes
It is a metal oxide film such as a ferroelectric material, a conductive material, an optical material, a magnetic material, or a superconducting material, which is exemplified below. (Ferroelectric material) Barium titanate (BaTiO ₃ ),
Strontium titanate (SrTiO ₃ ), lead titanate (PbTiO ₃ ), zirconium titanate (ZrTiO 3
₃ ), barium strontium titanate ((Ba, S
r) TiO ₃ ), lanthanum titanium oxide (La ₂ Ti ₂
O ₇ ), titanium strontium zirconate barium ((Ba, Sr) (Ti, Zr) O ₃ ), titanium
Lead zirconate (Pb (Zr, Ti) O ₃ ), strontium niobium titanate ((Nb) SrTiO ₃ ),
Tin barium titanate (Ba (Ti, Sn) O ₃ ),
Yttrium manganate (YMnO ₃ ) (conductive material) tin / indium oxide (ITO), zinc oxide (ZnO), tin oxide (SnO ₂ ), lanthanum titanate (LaTiO ₃ ), indium zinc oxide (In ₂
O ₃ -ZnO), antimony tin oxide (SbSnO
₂ ), indium oxide (In ₂ O ₃ ), zinc-tin-indium oxide ((Zn, Sn) In ₂ O ₃ ), alumina-zinc oxide (ZnO-Al ₂ O ₃ ), gallium-zinc oxide _{(ZnO-Ga 2 O 3)} ( optical material) titanium oxide (TiO _2), aluminum oxide (Al ₂ O _3), zirconium oxide (ZrO _2), lithium niobate (LiNbO _3), lithium iodate (LiIO ₃₎ , Potassium niobate (KNbO ₃ ), beryllium oxide (BeO), lead molybdate (PbMoO)
₃ ), zinc tungstate (PbWO ₄ ), lead oxide (P
bO), tungsten oxide (WO ₃ ), cobalt oxide (CoO), chromium oxide (Cr ₂ O ₃ ) (magnetic material) manganese zinc ferrite ((Mn, Zn)
O · Fe ₂ O _3), manganese copper ferrite ((Mn, C
_{u) O · Fe 2 O 3} ), barium ferrite (BaO ·
6Fe ₂ O ₃ ), iron oxide (Fe ₃ O ₄ ) (superconducting material) YBaCuO-based oxide The formation of the metal oxide film in the present invention is carried out by the conventionally known sputtering method, vacuum deposition method, ion plating method, C
It can be performed by any method such as the VD method. The substrate temperature at the time of forming the metal oxide film can be appropriately set within a temperature range of room temperature to 550 ° C., and the thickness of the metal oxide film can be appropriately set in consideration of the purpose of use and the like. , 100 to 10000Å can be set.

The light for irradiating the metal oxide film formed on the substrate has a wavelength of 400 nm or less, preferably 150 to
The wavelength of the emitted light is 400n.
If it exceeds m, the effect of the present invention cannot be obtained. As the light source for such light irradiation, the same light source as the light source described in the above method for forming the conductive film can be used.

The irradiation energy in the light irradiation is such that the metal oxide film is not crystallized, and the metal oxide film material to be used, the thickness of the metal oxide film, the light source to be used, and the purpose of use of the metal oxide film. It can be appropriately set according to the above. Here, not causing crystallization of the metal oxide film means not causing crystallization of the amorphous metal oxide film, or maintaining or decreasing the crystallinity of the crystalline metal oxide film. . As an example of irradiation energy, 350 is obtained by the DC sputtering method.
When irradiating a 2000 Å-thick tin-indium oxide (ITO) film formed at ℃ using a Xe-Cl excimer laser, the irradiation energy is about 150 mJ / cm 2.
^{About 2} is preferable, and if the irradiation energy is too high, crystallization will proceed, and as a result, the conduction electron density will decrease and a high resistance film will result.

By the light irradiation as described above, for example, the residual polarizability of a metal oxide film made of a ferroelectric material is increased, the resistivity of a metal oxide film made of a conductive material is reduced, and the metal oxide film made of an optical material is reduced. It is possible to increase the refractive index, reduce the coercive force of the metal oxide film made of a magnetic material, and reduce the number of crystal defects or irregularities in the metal oxide film made of a superconducting material.

As the substrate on which the metal oxide film is formed,
For example, a glass substrate, a ceramic substrate, a silicon substrate, a polycarbonate resin, a polyethylene terephthalate resin, a polyester resin, an epoxy resin, an acrylic resin, a polystyrene resin, or another resin substrate or a metal substrate can be used. It can be set as appropriate.

[0029]

Next, the present invention will be described in more detail with reference to examples. (Example 1) by placing the glass substrate having a thickness of 1.1mm on the substrate holder of the sputtering device, also target material in the target material mounting plate (In ₂ O ₃ -SnO ₂ sintered body (SnO ₂ 10% by weight) Attached.

Next, argon (A
r) Gas is introduced to set the atmospheric pressure to 5 mTorr, the substrate temperature to 25 ° C., and the thickness on the substrate to about 0.
A conductive film (ITO film) having a thickness of 3 μm was formed to prepare Sample A.

(ITO film forming conditions) Atmosphere gas: Ar = 100 sccm, O ₂ = 2 s
ccm ・ Atmospheric pressure: 5 mTorr ・ Hydrogen partial pressure: 10 × 10 ^-9 Torr or less ・ DC power: 2.5 kW ・ Film formation rate: 2 Å / sec The substrate (sample) on which the conductive film (ITO film) was formed as described above Sample A1 was prepared by irradiating A) with UV using a Hg-Xe UV lamp (wavelength main peak = 360 nm) so that the irradiation energy was as shown in Table 1 below.

Further, the substrate temperature was set to 300 ° C., and a conductive film (ITO) having a thickness of about 0.3 μm was formed on the substrate under the following film forming conditions.
A film is formed to prepare a sample B, and an Hg-Xe ultraviolet lamp (main peak of wavelength =
The sample B1 was prepared by irradiating ultraviolet rays with the irradiation energy shown in Table 1 below.

(ITO film forming conditions) Atmosphere gas: Ar = 10 sccm, O ₂ = 3.5
sccm ・ Atmospheric pressure: 5 mTorr ・ Hydrogen partial pressure: 10 × 10 ^-9 Torr or less ・ DC power: 150 W ・ Film formation rate: 9 Å / sec On the other hand, a substrate (sample) on which a conductive film (ITO film) is formed as described above A) to a He-Ne laser (wavelength 633).
nm) was used to irradiate ultraviolet rays so that the irradiation energies shown in Table 1 below were obtained to prepare comparative sample 1.

Further, the substrate (Sample A) on which the conductive film (ITO film) was formed as described above was heat-treated at 100 ° C. for 2 hours to prepare Comparative Sample 2.

Sample A, Sample A1, and
With respect to Sample B, Sample B1, and Comparative Samples 1 and 2, the crystallinity of the ITO film, the density of conduction electrons, and the resistivity were measured and evaluated by the following methods, and the results are shown in Table 1 below.

(Crystallinity Evaluation Method) The half-width of the following diffraction peak was measured by the X-ray diffraction method, and the change in crystallinity was evaluated from the change with respect to Sample A.

2θ = 30.08 ° (222) 2θ = 35.12 ° (400) 2θ = 60.08 ° (622) ・ Judgment of improvement of crystallinity: the half widths of the (222) plane and the (400) plane are No decrease or change, full width at half maximum of (622) plane Decrease in crystallinity: Full width at half maximum of (222) face and (400) face is increased, and full width at half maximum of (622) face is not decreased or changed (Measurement Method of Conduction Electron Density) VAN DER PAU
Hall measurement was performed by the W method.

(Measurement Method of Resistivity) Four Terminal Method or VAN
The measurement was performed by the DER PAUW method.

[0039]

[Table 1] As shown in Table 1, the resistivity of the sample A1 which was irradiated with ultraviolet rays having a wavelength of 400 nm or less was lower than that of the untreated sample A which was not subjected to ultraviolet irradiation or heat treatment. Further, this sample A1 has a lower crystallinity and no crystallization than the untreated sample A, while the density of conduction electrons is high, and the reduction of resistance is achieved by the improvement of the conduction electron density. It is thought that it was done.

It is also confirmed that the untreated sample B which has not been subjected to ultraviolet irradiation or heat treatment and the sample B1 which has been irradiated with ultraviolet rays having a wavelength of 400 nm or less are similar to the above-mentioned samples A and A1. Was done.

On the other hand, in the comparative sample 1 which was subjected to the light irradiation treatment using the light having the wavelength exceeding 400 nm, the conduction electron density was not improved and the resistivity was not lowered.

On the other hand, the comparative sample 2 obtained by subjecting the sample A to the heat treatment showed a slight decrease in resistivity. Further, although this comparative sample 2 has improved crystallinity as compared to the untreated sample A, no increase in the density of conduction electrons was observed. (Example 2) placing a glass substrate having a thickness of 1.1mm on the substrate holder of the sputtering device, also target material in the target material mounting plate (In ₂ O ₃ -SnO ₂ sintered body (SnO ₂ 10% by weight) Attached.

Next, argon (A
r) A gas is introduced to set the atmospheric pressure to 5 mTorr, the substrate temperature to 25 ° C., and the thickness on the substrate to about 0.
A conductive film (ITO film) of 3 μm was formed.

(ITO film forming conditions) Atmosphere gas: Ar = 100 sccm, O ₂ = 2 s
ccm ・ Atmospheric pressure: 5 mTorr ・ Hydrogen partial pressure: 10 × 10 ^-9 Torr or less ・ DC power: 2.5 kW ・ Film formation rate: 2 Å / sec Next, for the substrate on which this conductive film (ITO film) was formed Hg-Xe UV lamp (wavelength main peak = 3
60 nm), 10, 15, 20, 40, 60, 1
The treatment was carried out with eight kinds of irradiation times of 00, 200 and 500 minutes.

The conductive electron density and resistivity of each conductive film that had been subjected to the ultraviolet irradiation treatment and the untreated conductive film were measured in the same manner as in Example 1, and the results are shown in FIG.

As shown in FIG. 1, the density of conduction electrons was improved by the ultraviolet irradiation treatment for 10 minutes, and at the same time, the resistivity was decreased. As the irradiation time was increased, the conduction electron density was further improved and the resistance was decreased. The rate decreased. Example 3 A glass substrate having a thickness of 1.1 mm was placed on a substrate holder of a sputtering apparatus, and a target material (In ₂ O ₃ —SnO ₂ sintered body (SnO ₂ 10% by weight)) was mounted on a target material mounting plate. Attached.

Next, argon (A
r) A gas is introduced so that the atmospheric pressure is 5 mTorr, the substrate temperature is 25 ° C., and the thickness is about 15 on the substrate under the following film forming conditions.
A conductive film (ITO film) of 00Å was formed to prepare Sample C.

(ITO film forming conditions) Atmosphere gas: Ar = 100 sccm, O ₂ = 3 s
ccm ・ Atmospheric pressure: 5 mTorr ・ Hydrogen partial pressure: 10 × 10 ^-9 Torr or less ・ RF power: 250 W ・ Film formation rate: 2.6 Å / sec A substrate (sample) on which a conductive film (ITO film) was formed as described above C) is irradiated with Xe-Cl (wavelength 308 nm) excimer laser under the following conditions to obtain sample C1.
C3 was produced.

(Laser irradiation conditions) -Irradiation energy: Maximum 300 mJ / cm ² -Laser irradiation overlap ratio: 50% -Irradiation atmosphere: In air Sample C and samples C1 to C3 prepared as described above were compared with Example 1. Similarly, the crystallinity, conduction electron density, and resistivity of the ITO film were measured and evaluated, and the results are shown in Table 2 and FIG. 2 below.

[0050]

[Table 2] As shown in Table 2 and FIG. 2, as compared with the untreated sample C which was not subjected to the laser irradiation treatment, the samples C1 and C2 irradiated with the Xe-Cl excimer laser showed a decrease in resistivity. C2 has the lowest resistivity (5.87 × 1)
^0-4 Ω · cm), at which time crystallization did not occur and the density of conduction electrons was high. Then, in the sample C3 having a higher irradiation energy, the crystallization rapidly progresses and the resistivity is increased. From this, it can be said that the optimum value of the irradiation energy is approximately 100 mJ / cm ² in the Xe-Cl excimer laser irradiation of the sample C. Example 4 Using an ion plating apparatus, a conductive film (ITO film) having a thickness of about 0.3 μm was formed on a glass substrate having a thickness of 1.1 mm under the following film forming conditions at a substrate temperature of 25 ° C. Sample D was prepared.

(ITO film forming conditions) Atmosphere gas: Ar = 100 sccm, O ₂ = 3 s
ccm ・ Atmospheric pressure: 5 mTorr ・ Hydrogen partial pressure: 10 × 10 ^-9 Torr or less ・ Evaporation source: In ₂ O ₃ -SnO ₂ sintered body (Sn)
O ₂ 10% by weight) ・ RF power: 250 W ・ Film formation rate: 2.6 Å / sec For the substrate (Sample D) on which the conductive film (ITO film) is formed as described above, a Hg-Xe ultraviolet lamp (wavelength) (Main peak = 360 nm) was irradiated with ultraviolet rays so that the irradiation energy shown in Table 3 below was obtained, and thus a sample D1 was prepared.

Also, except that the substrate temperature was set to 300 ° C., a conductive film (ITO film) having a thickness of about 0.3 μm was formed on the substrate in the same manner as the sample D, and a sample E was prepared. (Sample B) was irradiated with ultraviolet rays using a Hg-Xe ultraviolet lamp (wavelength main peak = 360 nm) so that the irradiation energy was as shown in Table 3 below to prepare Sample E1.

On the other hand, with respect to the substrate (Sample D) on which the conductive film (ITO film) was formed as described above, the irradiation energy shown in Table 3 below was obtained by using a He-Ne laser (wavelength 633 nm). Comparative sample 1 was prepared by performing ultraviolet irradiation.

Further, the substrate (Sample D) on which the conductive film (ITO film) was formed as described above was heat-treated at 100 ° C. for 2 hours to prepare Comparative Sample 2.

Sample D, Sample D1, prepared as described above,
Example 1 for sample E, sample E1, and comparative samples 1 and 2
The crystallinity, the density of conduction electrons, and the resistivity of the ITO film were measured and evaluated in the same manner as in, and the results are shown in Table 3 below.

[0056]

[Table 3] As shown in Table 3, as compared with the untreated sample D which was not subjected to the ultraviolet irradiation or the heat treatment, the resistivity of the sample D1 which was subjected to the ultraviolet irradiation of the wavelength of 400 nm or less was lowered. Further, the sample D1 has lower crystallinity and no crystallization than the untreated sample D, on the other hand, the density of conduction electrons is high, and the reduction of resistance is achieved by the improvement of the conduction electron density. It is thought that it was done.

It was also confirmed that the untreated sample E which was not subjected to ultraviolet irradiation or heat treatment and the sample E1 which was irradiated with ultraviolet rays having a wavelength of 400 nm or less were similar to the samples D and D1. Was done.

On the other hand, in the comparative sample 1 which was subjected to the light irradiation treatment using the light having the wavelength exceeding 400 nm, the conduction electron density was not improved and the resistivity was not decreased.

On the other hand, the comparative sample 2 obtained by subjecting the sample D to the heat treatment has improved crystallinity as compared with the untreated sample D, but the density of conduction electrons is hardly increased, and the resistivity of the sample is decreased. The decrease was slight. (Example 5) Using a vacuum vapor deposition apparatus, a conductive film (ITO film) having a thickness of about 0.3 μm was formed on a glass substrate having a thickness of 1.1 mm under the following film forming conditions at a temperature of 25 ° C. F was produced.

(ITO film forming conditions) -Atmospheric pressure: 5 mTorr-Hydrogen partial pressure: 10 × 10 ^-9 Torr or less-Evaporation source: In ₂ O ₃ -SnO ₂ sintered body (Sn)
O ₂ 10 wt%) ・ RF power: 250 W ・ Film formation rate: 2.6 Å / sec For the substrate (Sample F) on which the conductive film (ITO film) is formed as described above, a Hg-Xe ultraviolet lamp (wavelength) (Main peak = 360 nm) was irradiated with ultraviolet rays so that the irradiation energy was as shown in Table 4 below to prepare sample F1.

Further, except that the substrate temperature was set to 300 ° C., a conductive film (ITO film) having a thickness of about 0.3 μm was formed on the substrate in the same manner as the sample F, and a sample G was prepared. (Sample B) was irradiated with ultraviolet rays using an Hg-Xe ultraviolet lamp (wavelength main peak = 360 nm) so that the irradiation energy was as shown in Table 4 below, to prepare Sample G1.

On the other hand, with respect to the substrate (Sample F) on which the conductive film (ITO film) was formed as described above, the irradiation energy shown in Table 4 below was obtained by using a He-Ne laser (wavelength 633 nm). Comparative sample 1 was prepared by performing ultraviolet irradiation.

Further, the substrate (Sample F) on which the conductive film (ITO film) was formed as described above was heat-treated at 100 ° C. for 2 hours to prepare Comparative Sample 2.

Sample F, Sample F1, manufactured as described above,
Example 1 for sample G, sample G1, and comparative samples 1 and 2
The crystallinity, the density of conduction electrons, and the resistivity of the ITO film were measured and evaluated in the same manner as in, and the results are shown in Table 4 below.

[0065]

[Table 4] As shown in Table 4, the resistivity of the sample F1 irradiated with ultraviolet rays having a wavelength of 400 nm or less was lower than that of the untreated sample F which was not subjected to ultraviolet irradiation or heat treatment. Further, this sample F1 has a lower crystallinity than the untreated sample F and no crystallization has occurred. On the other hand, the density of conduction electrons is high. It is considered that this has been achieved.

Also, it is confirmed that the untreated sample G which has not been subjected to the ultraviolet irradiation and the heat treatment and the sample G1 which has been subjected to the ultraviolet irradiation of the wavelength of 400 nm or less are the same as the above-mentioned samples F and F1. Was done.

On the other hand, in the comparative sample 1 which was subjected to the light irradiation treatment using the light having the wavelength exceeding 400 nm, the conduction electron density was not improved and the resistivity was not lowered.

On the other hand, the comparative sample 2 obtained by subjecting the sample F to the heat treatment showed a slight decrease in resistivity and improved crystallinity as compared with the untreated sample F, but the density of conduction electrons was increased. No increase was observed. (Example 6) P was formed on a silicon wafer having a thickness of 1.1 mm.
A substrate on which a tNi alloy is formed is placed on a substrate holder of a sputtering device, and a target material (Zr / Ti alloy plate, PbO pellet) is used as a target material mounting plate.
Attached.

Next, argon (A
r) Introducing a gas, the atmospheric pressure is 10 mTorr, the substrate temperature is 400 ° C., and the thickness of the substrate is about 0.
2 μm ferroelectric thin film (PbZrTiO ₃ , hereinafter PZT
Sample H was prepared by forming a film).

(PZT film forming conditions) Atmosphere gas: Ar = 100 sccm, O ₂ = 2 s
ccm-Atmospheric pressure: 10 mTorr-Hydrogen partial pressure: 10 ^-8 Torr or less-DC power: 2000 W-Film forming rate: 0.2 nm / sec A substrate (sample) on which a ferroelectric thin film (PZT film) is formed as described above H) was irradiated with ultraviolet rays at room temperature and atmospheric pressure using a Hg-Xe ultraviolet lamp (wavelength main peak = 360 nm) so that the irradiation energy was as shown in Table 5 below to prepare Sample H1. did.

On the other hand, as described above, the ferroelectric thin film (PZT
Comparative substrate 1 was prepared by irradiating the substrate (sample H) on which the film was formed with a He—Ne laser (wavelength 633 nm) so that the irradiation energy was as shown in Table 5 below.

Further, as described above, the ferroelectric thin film (PZT
For a substrate (sample H) on which a film) is formed, 500 ° C., 1
Comparative sample 2 was prepared by performing heat treatment for a period of time.

Sample H, Sample H1 manufactured as described above,
The comparative samples 1 and 2 were measured and evaluated for crystallinity and DE hysteresis characteristics (evaluation of residual polarization Pr value) of the PZT film by the following methods, and the results are shown in Table 5 below.

(Crystallinity evaluation method) The half widths of the diffraction peaks of the (112) plane and the (301) plane of perovskite type (Pb, Zr) TiO ₃ were measured by the X-ray diffraction method, and the half value width of the diffraction peak for the sample H was measured. Changes in sex were evaluated.

Determination of improvement of crystallinity: (112) plane and (3)
Decrease in half-value width of the (01) plane ・ Judgment of decrease in crystallinity: Increase in half-value width of the (112) plane and the (301) plane (Method of measuring remanent polarization Pr) DE by PtNi electrode
Draw a hysteresis curve and draw the remanent polarization Pr from that loop.
I asked.

[0076]

[Table 5] As shown in Table 5, the residual polarization value was increased in the sample H1 which was irradiated with ultraviolet rays having a wavelength of 400 nm or less, as compared with the untreated sample H which was not subjected to ultraviolet irradiation or heat treatment.
In addition, the crystallinity of this sample H1 did not change as compared with the untreated sample H, and it is considered that the high remanent polarization was achieved by the change of the film morphology.

On the other hand, in the comparative sample 1 which was subjected to the light irradiation treatment using the light having the wavelength exceeding 400 nm, the remanent polarization value did not increase.

On the other hand, the comparative sample 2 obtained by subjecting the sample H to the heat treatment had improved crystallinity as compared with the untreated sample H, but the remanent polarization value slightly increased. (Example 7) A 1.1 mm thick glass substrate was placed on a substrate holder of a sputtering apparatus, and a target material (Mn / Zn alloy plate, Fe) was used as a target material mounting plate.
₃ O ₄ pellets) was attached.

Next, argon (A
r) Introducing gas, setting the atmospheric pressure to 5 mTorr, the substrate temperature to 450 ° C., and the thickness of about 0.2 on the substrate under the following film forming conditions.
μm ferroelectric thin film ((Mn, Zn) O.Fe ₂ O ₃ ,
(Hereinafter referred to as MnZn ferrite film) was formed to prepare Sample I.

(MnZn ferrite film forming condition) Atmosphere gas: Ar = 100 sccm, O ₂ = 2 s
ccm-Atmospheric pressure: 5 mTorr-Hydrogen partial pressure: 10 ^-8 Torr or less-DC power: 2000 W-Film formation rate: 0.5 nm / sec A substrate (sample) on which a ferromagnetic thin film (MnZn ferrite film) was formed as described above Sample I1 was prepared by irradiating I) with ultraviolet light at room temperature under atmospheric pressure so that the irradiation energy shown in Table 6 below was obtained using a Hg-Xe ultraviolet lamp (wavelength main peak = 360 nm). did.

On the other hand, as described above, the ferromagnetic thin film (MnZn
For the substrate (Sample I) on which the ferrite film was formed,
Table 6 below using an e-Ne laser (wavelength 633 nm)
Comparative sample 1 was prepared by irradiating with ultraviolet light so that the irradiation energy shown in FIG.

As described above, the ferromagnetic thin film (MnZn
5 for the substrate (Sample I) on which the ferrite film was formed
Comparative sample 2 was produced by performing heat treatment at 00 ° C. for 1 hour.

Sample I, Sample I1, prepared as described above,
For Comparative Samples 1 and 2, the crystallinity and magnetic hysteresis characteristics (coercive force H
(evaluation of c value) was measured and evaluated, and the results are shown in Table 6 below.

(Crystallinity Evaluation Method) The full width at half maximum of the diffraction peaks of the (111) plane and (110) plane of the spinel type ferrite was measured by the X-ray diffraction method, and the change in crystallinity was evaluated from the change with respect to Sample I. .

Determination of crystallinity improvement: (111) plane and (1)
10) Full width at half maximum is reduced. • Decrease in crystallinity: Full width at half maximum of (111) plane and (110) plane is increased.
Then, the magnetic hysteresis curve of the sample was drawn, and the coercive force Hc was determined from the loop.

[0086]

[Table 6] As shown in Table 6, the coercive force of Sample I1 irradiated with ultraviolet light having a wavelength of 400 nm or less was decreased as compared to untreated Sample I which was not subjected to ultraviolet irradiation or heat treatment. Further, the crystallinity of this sample I1 is not changed as compared with the untreated sample I, and the crystal grain boundary is reduced due to the change of the film morphology.
As a result, it is considered that the low coercive force was achieved.

On the other hand, in the comparative sample 1 which was subjected to the light irradiation treatment using the light having the wavelength exceeding 400 nm, the coercive force did not decrease.

On the other hand, the comparative sample 2 obtained by subjecting the sample I to the heat treatment had improved crystallinity as compared to the untreated sample I, but the coercive force was slightly reduced.

[0089]

As described in detail above, according to the present invention, after the conductive film is formed on the substrate, the conductive film is irradiated with light having a wavelength of 400 nm or less so as not to cause crystallization. The density of conduction electrons in the film is increased to improve the conductivity, and the resistivity of the conductive film can be lowered. This lowering of resistance does not have an annealing treatment, so that the substrate is not adversely affected by heat. A low resistance conductive film can be formed even on a substrate having low heat resistance. Further, after forming the metal oxide film on the substrate, the characteristics of the metal oxide film are changed by irradiating the metal oxide film with light having a wavelength of 400 nm or less so as not to cause crystallization.
For example, the residual polarizability is increased by changing the film morphology of the metal oxide film as the ferroelectric thin film, and the coercive force is reduced by decreasing the crystal grain boundaries by changing the film morphology of the metal oxide film as the ferromagnetic thin film. It can be lowered, and a desired metal oxide film can be formed without performing annealing treatment after film formation.

[Brief description of drawings]

FIG. 1 is a diagram showing the relationship between the irradiation time of ultraviolet rays on a conductive film and the conduction electron density and resistivity of the conductive film.

FIG. 2 is a diagram showing a relationship between laser irradiation energy and resistivity of a conductive film.

Claims (5)

[Claims] 1. A method for forming a conductive film, which comprises forming a conductive film on a substrate and then irradiating light having a wavelength of 400 nm or less with irradiation energy in a range that does not cause crystallization of the conductive film. 2. The substrate temperature at the time of forming the conductive film is set in the range of room temperature to 200 ° C.
The method for forming a conductive film according to [4]. 3. The conductive film according to claim 1, wherein the conductive film is formed by any one of a sputtering method, a vacuum deposition method, an ion plating method, and a CVD method. Method. 4. A method for forming a metal oxide film, comprising forming a metal oxide film on a substrate and then irradiating the metal oxide film with light having a wavelength of 400 nm or less with an irradiation energy in a range that does not cause crystallization. . 5. The method for forming a metal oxide film according to claim 4, wherein the metal oxide film is formed by any one of a sputtering method, a vacuum deposition method, an ion plating method and a CVD method.