JPH11172421A - Method and apparatus for manufacturing fluoride thin film - Google Patents

Abstract

(57) [Summary] [Problem] λ = 400 with safety, convenience, and environmental friendliness
Provided are a method and an apparatus for manufacturing a fluoride thin film having small film loss in a wavelength region of nm or less. SOLUTION: In a method of manufacturing a fluoride thin film in which a fluorine compound 3 is scattered from an evaporation source 2 in a vacuum atmosphere to form a film on a substrate 5, during film formation, a gasification device 4 enters a vacuum chamber 1 into a vacuum chamber 1; Xenon fluoride gas is scattered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for producing a fluoride thin film usable in an ultraviolet region.

[0002]

2. Description of the Related Art In recent years, in order to increase the degree of integration of semiconductor devices, there is an increasing demand for a high-resolution reduction projection exposure apparatus (stepper) for semiconductor manufacturing. One method of increasing the resolution of photolithography using this stepper is to shorten the wavelength of the light source.

Recently, a stepper using a high-output excimer laser as a light source that can oscillate light in a shorter wavelength range than a mercury lamp has begun to be put into practical use. Here, the excimer laser as a light source is a KrF excimer laser (λ
= 248 nm) or ArF excimer laser (λ = 193
nm). In an optical system of a stepper using an excimer laser as a light source, an anti-reflection film and a mirror (reflection increasing film) for bending the optical path are used to reduce the amount of light loss and flare and ghost due to surface reflection of optical elements such as lenses Need to be formed.

Here, when an optical thin film (anti-reflection film or mirror) is made of a film material having a large absorption for light having an excimer laser wavelength or a film material having a low laser resistance, a loss of light amount due to absorption and absorption heat generation. Changes in the substrate surface and film destruction. For this reason, as a film substance used for an optical thin film formed on an optical element such as a lens, a substance having low absorption and high laser resistance is desirable.

[0005] Film materials that can be used at the wavelength of the excimer laser mainly include fluorine compounds such as magnesium fluoride (MgF ₂ ) and some oxides (such as aluminum oxide (Al).
₂ O ₃ ) and silicon dioxide (SiO ₂ )), an optical element having an optical thin film made of a fluorine compound has a smaller light quantity loss.

When forming this fluoride thin film, a vacuum evaporation method, a sputtering method, or the like, which is a physical film forming method, has been mainly used in a vacuum atmosphere as a simple method.

[0007]

However, when a resistive heating is used as an evaporation source when forming a fluoride thin film by a vacuum vapor deposition method, a fluorine-containing vapor-deposited material is deposited on a resistive heating boat by heating on a resistive heating boat. Dissociation occurs. Also,
When an electron gun is used, separation of fluorine and metal atoms is caused by electron irradiation in a vapor deposition material made of a fluorine compound.

[0008] For this reason, the fluorine-deficient deposition material is scattered from the deposition source, and the residual oxygen in the vacuum chamber is combined with the metal atoms of the fluorine-defective deposition material to form oxyfluoride (MF _x O _y). , M: metal atoms) were formed, or a fluoride thin film with fluorine deficiency was formed. In addition, in the film formation process in a vacuum atmosphere, when the film is formed by the ion assist method of irradiating the surface of the fluoride thin film being formed with an ion beam, the residual oxygen in the vacuum chamber is caused due to the above-described cause. Is bonded to the metal atoms of the fluorine-deficient deposition material, and fluorine, which is a light element, is selectively sputtered from the fluoride thin film being formed, which further generates fluorine deficiency. By bonding the residual oxygen to the metal atoms, an oxyfluoridated (MF _x O _y , M: metal atom) fluoride thin film or a fluoride thin film with fluorine deficiency remaining was formed.

[0009] In forming a fluoride thin film by sputtering, when a target made of a fluorine compound is bombarded with an ion beam, the irradiation beam energy is as high as several hundreds eV to several keV. Selective sputtering of fluorine is inevitable.

In this case as well, the metal atoms bonded to the fluorine atoms are separated from each other, the fluorine-deficient deposition material is scattered from the deposition source, and the residual oxygen in the vacuum chamber is reduced to the metal of the fluorine-defective deposition material. By bonding with atoms, a fluorinated fluoride thin film (MF _x O _y , M: metal atom) or a fluoride thin film with a fluorine deficiency remaining was formed.

In the film formation process by ion beam sputtering, when the surface of the fluoride thin film being formed is irradiated with an ion beam (dual ion beam sputtering process), the surface of the fluoride thin film being formed is further reduced. Light element fluorine is selectively sputtered. Then, the residual oxygen in the vacuum chamber enters where the fluorine has escaped,
Oxyfluoride-forming (MFxOy, M: metal atom) fluoride thin film or fluoride thin film with fluorine deficiency remaining was formed by bonding oxygen instead of fluorine to a metal atom.

In the case of a fluoride thin film partially oxyfluoridated or a fluoride thin film in which a fluorine deficiency remains, there is no problem particularly in the visible region due to the fluorine deficiency. Loss due to absorption and scattering (hereinafter, referred to as “film loss”) has a wavelength λ = 400 n
m to ultraviolet vacuum region (λ = 120 nm)
(Up to the vicinity), there is a problem that the transmittance greatly increases in a short wavelength region, and the transmittance as an optical component decreases.

This is a phenomenon that cannot be ignored in an optical system having a large number of lenses. For example, a reduction projection exposure apparatus using a light source in the ultraviolet region in the manufacture of integrated circuits usually has one
Since it has an optical system having an illumination system composed of a large number of 5 to 20 lenses and a projection system composed of substantially the same number of lenses (the number of surfaces is twice the number of lenses), Even a slight loss of film will cause a significant decrease in transmittance.

One way to solve this problem is as follows:
A method of directly introducing fluorine gas into the vacuum chamber is conceivable. However, fluorine has a very strong chemical action, reacts directly with all elements, and is a highly toxic and highly corrosive stimulant.If fluorine gas is directly introduced into the vacuum chamber, the vacuum chamber will be corroded. Besides being problematic, it is very dangerous for the human body.

In order to cope with this, a special protective film must be provided on the inner surface of the gas supply pipe, and a very airtight facility must be provided for the treatment of waste gas. There was a problem that the nature and environmental properties were largely lacking. The present invention has been made in view of the above problems, and provides a method and an apparatus for manufacturing a fluoride thin film having safety, convenience, and environmental friendliness, and having a small film loss in a wavelength region of λ = 400 nm or less. The purpose is to do.

[0016]

According to the first aspect of the present invention, there is provided a method of manufacturing a fluoride thin film, wherein a fluorine compound is scattered from an evaporation source in a vacuum atmosphere to form a film on a substrate.
Xenon fluoride gas is scattered during film formation.
Therefore, according to the first aspect of the present invention, the wavelength 40
Even in a short wavelength region of 0 nm or less, a fluoride thin film with small film loss can be formed.

According to a second aspect of the present invention, in forming a fluoride thin film on a substrate by sputtering, a target made of a metal or a fluorine compound is disposed, and xenon fluoride gas or fluoride is used. A mixed gas of a xenon gas and a rare gas is introduced as a sputtering gas, the target is bombarded by the sputtering gas, and a metal or a fluorine compound is scattered to form a film.

Therefore, according to the second aspect of the present invention, while compensating for the impact of the sputtering gas on the target and the fluorine deficiency generated during the film forming process, the wavelength 40
Even in a short wavelength region of 0 nm or less, a fluoride thin film with small film loss can be formed. Further, the invention according to claim 3 uses a sputtering method to form a fluoride thin film on a substrate, arrange a metal or fluorine compound target, introduce a rare gas as a sputtering gas,
A film is formed by bombarding a target with this rare gas to scatter a metal or a fluorine compound. During the film formation, xenon fluoride gas or a mixed gas of xenon fluoride gas and a rare gas is introduced. is there.

Therefore, according to the third aspect of the present invention, a fluoride thin film having a small film loss even in a short wavelength region of 400 nm or less while compensating for the impact of the rare gas on the target and fluorine deficiency generated during the film formation process. Can be formed. According to a fourth aspect of the present invention, in the method of manufacturing a fluoride thin film according to the first, second, or third aspect, the ion beam is applied to the surface of the fluoride thin film being formed during the film formation. Is irradiated.

Therefore, according to the present invention, a short wavelength of 400 nm or less can be obtained while supplementing fluorine deficiency caused by selective sputtering of fluorine from a thin film being formed by ion beam irradiation. Even in the region, a fluoride thin film with small film loss can be formed. Also,
According to a fifth aspect of the present invention, in forming a fluoride thin film on a substrate by using an ion plating method, an evaporation source for scattering a metal or a fluorine compound is arranged, and xenon fluoride gas is formed during the film formation. Alternatively, a mixed gas of xenon fluoride gas and a rare gas is introduced to generate plasma, and the metal or fluorine compound scattered from the evaporation source is ionized in the plasma.

According to the fifth aspect of the present invention, the film can be formed even in a short wavelength region of 400 nm or less while supplementing heating in an evaporation source, ionization in plasma, and fluorine deficiency generated in a film forming process. A fluoride thin film with small loss can be formed.

According to a sixth aspect of the present invention, there is provided an apparatus for manufacturing a thin film of a fluoride, comprising: a film forming chamber in which an evaporation source for scattering a fluorine compound as a deposition material and a substrate holder for holding a substrate are provided; An exhaust unit for exhausting the inside of the chamber and a gas scattering unit for scattering xenon fluoride gas into the film formation chamber are provided. Therefore, according to the invention of claim 6, it is possible to form a fluoride thin film having small film loss even in a short wavelength region of a wavelength of 400 nm or less, while compensating for fluorine deficiency caused by heating in an evaporation source.

According to a seventh aspect of the present invention, there is provided an apparatus for producing a thin film of a fluoride, wherein a target holder for holding a sputtering target made of a metal or a fluorine compound, and a substrate holder for holding a substrate are arranged inside. A chamber, a power application unit for applying a predetermined power to the target held by the target holder, an exhaust unit for exhausting the inside of the deposition chamber, and a xenon fluoride gas or a xenon fluoride gas inside the deposition chamber. A gas introduction unit for introducing a mixed gas with a rare gas as a sputtering gas.

Therefore, according to the present invention, the wavelength of 40 is compensated while compensating for the impact of the sputtering gas on the target and the fluorine deficiency generated during the film formation process.
Even in a short wavelength region of 0 nm or less, a fluoride thin film with small film loss can be formed. An apparatus for manufacturing a thin film of a fluoride according to claim 8, further comprising: a deposition chamber in which an evaporation source for scattering a metal or a fluorine compound as a deposition material and a substrate holder for holding a substrate are disposed; A power application unit that applies a predetermined power to the substrate held in the chamber, an exhaust unit that exhausts the film formation chamber, and a mixture of xenon fluoride gas or a mixture of xenon fluoride gas and a rare gas in the film formation chamber. The apparatus includes a gas introduction unit that introduces a gas, and a plasma generation unit that generates plasma of the gas introduced by the gas introduction unit between the evaporation source and the substrate.

Therefore, according to the present invention, the film can be formed even in a short wavelength region of 400 nm or less while compensating for the fluorine deficiency generated during the heating in the evaporation source, the ionization in the plasma, and the film formation process. A fluoride thin film with small loss can be formed.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) First, a first embodiment of the present invention will be described with reference to FIGS. Note that the first embodiment corresponds to claims 1 and 6.

FIG. 1 shows the production of the fluoride thin film of the first embodiment.
FIG. 1 is a schematic view of a vacuum evaporation apparatus 10 used in a fabrication method. Figure
2 is a diagram showing a xenon fluoride gasifier 4.
Vacuum chamber 1 of vacuum deposition apparatus 10 shown in FIG.
In the (film formation chamber), a deposition material 3 made of a fluorine compound is placed.
Holds deposition source (resistance heating boat) 2 and substrate 5
And a substrate holder 6 capable of rotating and revolving,
Xenon (XeF _Two) Gasifier 4 (gas of claim 6)
(Corresponding to the scattering portion).

The xenon fluoride gasifier 4 is preferably provided at a position which is not affected by radiant heat from the evaporation source 2. As shown in FIG. 2, the gasifier 4 includes a nickel container (boat) 12 containing a xenon fluoride 11.
And a temperature control mechanism 13 for controlling the temperature of the container 12.

The temperature control mechanism 13 is a mechanism in which a cooling pipe for flowing and cooling liquid nitrogen in a vacuum and an infrared heater for heating are provided. here,
Xenon fluoride 11 is a substance having a melting point of about 127 ° C. at atmospheric pressure, and has a sublimation property at a temperature lower than the melting point. Therefore, the xenon fluoride 11 is gasified by setting the temperature to an appropriate temperature by the temperature control mechanism 13 provided in the container 12,
It can be scattered in the vacuum chamber 1.

Further, the partial pressure of the xenon fluoride gas in the vacuum chamber 1 can be kept constant by the temperature control mechanism 13. The set temperature of the temperature control mechanism 13 is preferably about 100 ° C. to 130 ° C., and the partial pressure of the xenon fluoride gas in the vacuum chamber 1 is preferably set to 5 × 10 ⁻⁵ Torr or more by the temperature control mechanism 13.

A vacuum pump (not shown) is connected to the vacuum chamber 1 of the vacuum vapor deposition apparatus 10, and an exhaust port 7 is provided.
It can be exhausted from. Hereinafter, a method of manufacturing the fluoride thin film according to the first embodiment will be described. Prior to film formation, a quartz glass substrate 5 is prepared and subjected to ultrasonic cleaning, and then set on a substrate holder 6 provided in the vacuum chamber 1. Then, the substrate 5 is heated to about 200 ° C to 400 ° C. The inside of the vacuum chamber 1 is 5 × ^10-6 T
The chamber is evacuated to orr to 5 × 10 ⁻⁷ Torr.

At the time of film formation, the vapor deposition material 3 placed on the vapor deposition source 2 is heated and evaporated, and scattered toward the substrate 5 to form a thin film on the substrate 5. Xenon fluoride (XeF ₂ ) sublimated in the gasifier 4 and scattered in the vacuum chamber 1
Some of the gas dissociates in a vacuum atmosphere. Then, xenon and fluorine are in a state of radicals, ions, atoms and the like.

Since these fluorines have high reactivity, the fluorine-deficient vapor-depositing material 3 is scattered toward the substrate 5 by heating on the vapor-deposition source (resistance heating boat) 2 toward the substrate 5 and in the film-forming process. I can make up for it. The total pressure in this film forming process is preferably 1 × 10 ⁻⁵ Torr.
r to 3 × 10 ⁻⁴ Torr. Also, the partial pressure of xenon fluoride is preferably 1 × 10 ^over 5 Torr~2 × 10 ^-4
Torr.

Further, since xenon fluoride itself has an action as a fluorinating agent, it has an effect of compensating for a fluorine-deficient substance. In the process of forming such a fluoride thin film, a small amount of xenon (Xe) atoms may be trapped in the fluoride thin film. But,
Xenon atoms are rare gases and have very low reactivity, so they hardly affect the increase in film loss.

As described above, the fabrication of the first embodiment
The fluoride thin film formed by the method
Normal non-gas that does not scatter non-gas into the vacuum chamber 1
Wavelength λ = 400 compared to a film formed by the blank evaporation method.
Short-wave from ultraviolet region below nm to vacuum ultraviolet region
Film loss can be reduced in a long region. Fluorine compound
As the deposition material 3 made of, for example, aluminum fluoride
(AlF_Three), Barium fluoride (BaF_Two) 、 Calcium fluoride
Cium (CaF_Two), Thiolite (Na_FiveAl_ThreeF₁₄) 、 ク
Riolite (Na_ThreeAlF₆), Gadolinium fluoride (Gd
F _Three), Lead fluoride (PbF_Two), Lanthanum fluoride (La
F_Three), Lithium fluoride (LiF), magnesium fluoride
(MgF_Two), Neodymium fluoride (NdF_Three) 、 Fluoro nato
Lithium (NaF), Yttrium Fluoride (YbF_Three),
Yttrium fluoride (YF_Three) Can be used
You.

In the first embodiment, the evaporation source 2
Although the example of using resistance heating was explained above, when using an electron gun,
Similarly, the fluorine deficiency caused by the irradiation of the electron gun
While supplementing, a fluoride thin film can be formed on the substrate 5. Further
In the above-described first embodiment, xenon fluoride is used.
XeF_TwoAlthough the example using only XeF has been described,_TwoAnd XeF
_FourXenon fluoride mixed with _FourConsist only of
Even when using xenon fluoride, the wavelength λ = 400 nm
Fluoride thin film with reduced film loss in the following short wavelength region
A film can be formed.

(Modification of First Embodiment) Next, a modification of the first embodiment will be described with reference to FIG. Note that a modification of the first embodiment also corresponds to claims 1 and 6. FIG. 3 is a schematic diagram of a vacuum evaporation apparatus 20 used in a method for manufacturing a fluoride thin film according to a modification of the first embodiment.

The vacuum deposition apparatus 20 shown in FIG. 3 is similar to the vacuum deposition apparatus 10 shown in FIG. 1 except that a gasifier 8 of xenon fluoride (XeF ₂ ) is mounted outside the vacuum chamber 1. In the vacuum chamber 1, an evaporation source (resistance heating boat) 2 for introducing an evaporation material 3 made of a fluorine compound, and a substrate holder 6 that holds a substrate 5 and can rotate and revolve are arranged in a vacuum chamber 1. I have.

The gasifier 8 of this modification includes a nickel container (boat) 12 containing xenon fluoride 11, a temperature adjusting mechanism 13 for adjusting the temperature of the container 12, and a thermometer 14 for detecting the temperature of the container 12. (For example, a thermocouple), and a temperature controller 15 connected between the temperature adjustment mechanism 13 and the thermometer 14. The temperature control mechanism 13 is a refrigerant supply pipe b for flowing a refrigerant gas, cooling water, or liquid nitrogen in a vacuum to cool the xenon fluoride 11.
And an infrared heater a for heating the xenon fluoride 11.

The temperature controller 15 controls the power applied to the infrared heater a, the refrigerant temperature, and the flow rate based on a comparison between the temperature signal from the thermometer 14 and the control target temperature. The gasifier 8 configured as described above is connected to a side wall (left side in FIG. 3) of the vacuum chamber 1 via a gas supply pipe 21. The gasification device 8 and the gas supply pipe 21 correspond to a gas scattering portion according to claim 6.

A flow regulating valve 22 for regulating the flow of xenon fluoride gas introduced from the gasifier 8 into the vacuum chamber 1 is provided in the gas supply pipe 21. Further, a pressure controller 23 is connected to the flow control valve 22. The pressure controller 23 is connected to a pressure gauge 24 that detects a gas pressure in the vacuum chamber 1. Thereby, the flow rate of the xenon fluoride gas into the vacuum chamber 1 can be adjusted based on the gas pressure in the vacuum chamber 1.

In the vacuum evaporation apparatus 20 according to the modified example of the first embodiment, the evaporation material 3 placed on the evaporation source 2 is heated and evaporated, and the substrate 5 (about 200 ° C. to 400 ° C.) is heated.
When forming by causing splashing toward the, from the gasifier 8 attached to the outside of the vacuum chamber 1, a vacuum chamber 1 (5 × 10 ^over 6 Torr~5 × 10 ^-7 Torr)
Xenon fluoride gas is introduced therein.

At this time, the set temperature of the temperature control mechanism 13 provided in the gasifier 8 is approximately 100 ° C. to 130 ° C.
° C is preferable, and the temperature control mechanism 13 and the flow control valve 22
Thereby, the partial pressure of the xenon fluoride gas in the vacuum chamber 1 can be adjusted to an arbitrary value. In this case, the partial pressure of xenon fluoride is, 1 × 10 ^over 5 Torr～2
× 10 ⁻⁴ Torr is preferable.

If necessary, constant temperature control for keeping the temperature of xenon fluoride constant is also performed. In this case, the preferable partial pressure range of xenon fluoride is also 1 × 10 ⁻⁵ Torr.
２2 × 10 ⁻⁴ Torr. The total pressure during the film formation process is preferably 1 × 10 ⁻⁵ Torr in any case.
^-3 × 10 ⁻⁴ Torr.

Part of the xenon fluoride (XeF ₂ ) gas sublimated in the gasifier 8 and scattered in the vacuum chamber 1 is dissociated in a vacuum atmosphere. Then, xenon and fluorine are in a state of radicals, ions, atoms and the like. Since these fluorines are highly reactive, they can compensate for the fluorine deficiency in the process in which the fluorine-deficient deposition material 3 is scattered toward the substrate 5 by the heating on the deposition source (resistance heating boat) 2 and the film formation process. it can.

Therefore, even the fluoride thin film formed by the manufacturing method of the modification of the first embodiment is compared with a film formed by a normal vacuum deposition method in which xenon fluoride gas is not scattered in the vacuum chamber 1. And the wavelength λ = 400
The film loss can be reduced in a short wavelength region from an ultraviolet region of nm or less to a vacuum ultraviolet region.

In the modification of the first embodiment, the gasifier 8 is provided with the thermometer 14 and the temperature controller 15, but the cooling water or the like at a constant temperature can flow through the refrigerant supply pipe b. If so, the thermometer 14 and the temperature controller 15 need not be provided. (Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. The first embodiment corresponds to claims 1, 4 and 6.

FIG. 4 is a schematic view of a vacuum evaporation apparatus 30 used in the method for manufacturing a fluoride thin film according to the second embodiment. The vacuum deposition apparatus 30 forms a film by an ion beam assist method. In the vacuum chamber 1 of the vacuum deposition apparatus 30 shown in FIG. 4, as in the vacuum deposition apparatus 10 shown in FIG. In addition to the arrangement, a substrate holder 6 that can rotate and revolve, and a gasifier 4 of xenon fluoride (XeF ₂ ) (see FIG. 2, corresponding to the gas scattering portion of claim 6) are arranged. And an ion gun 9 connected to the ion introduction tube 9a.

Ar ions are used as the ions irradiated from the ion gun 9. In order to minimize the film loss, the ion beam irradiation energy should be about 1
μA / cm ² ~7μA / cm ² is preferable. In addition, a vacuum pump (not shown) is connected to the vacuum chamber 1 of the vacuum vapor deposition device 30 so that the gas can be exhausted from the exhaust port 7.

Hereinafter, a method for manufacturing a fluoride thin film according to the second embodiment will be described. Prior to film formation, a quartz glass substrate 5 is prepared and subjected to ultrasonic cleaning, and then set on a substrate holder 6 provided in the vacuum chamber 1. Then, the substrate 5 is heated to about 200 ° C to 400 ° C. Further, the vacuum chamber 1, 5 × 10 ^over 6 Torr~5 × 10 ^-7 To
Evacuate to rr.

At the time of film formation, the evaporation material 3 placed on the evaporation source 2 is heated and evaporated to be scattered toward the substrate 5, and the ion beam extracted from the ion gun 9 is applied to the substrate 5.
And a thin film is formed on the substrate 5 by the ion beam assist method. Xenon fluoride (XeF ₂ ) sublimated in the gasifier 4 and scattered in the vacuum chamber 1
Part of the gas is dissociated in a vacuum atmosphere as in the first embodiment, but more xenon fluoride is dissociated by entering the ion beam irradiation range, and xenon and fluorine are converted into radicals, ions, and atoms. And so on.

Since these fluorines have high reactivity, the fluorine-deficient vapor deposition material 3 scattered toward the substrate 5 due to the heating of the vapor on the vapor deposition source (resistance heating boat) 2 toward the substrate 5 and the fluorine deficiency generated in the film forming process, Alternatively, when a film is formed by an ion beam assist method, fluorine deficiency generated by selectively sputtering fluorine from a thin film being formed can be compensated.

As described above, the xenon fluoride gas is more dissociated by entering the ion beam irradiation range than in a vacuum atmosphere, and more xenon and fluorine are in a state of radicals, ions, atoms, and the like. The effect of supplementing fluorine deficiency is great. In addition, since xenon fluoride itself has a function as a fluorinating agent, it has an effect of supplementing fluorine-deficient ones.

The total pressure in the film forming process is 1 × 10 ⁻⁵ T
is preferably in the range of orr~3 × 10 ^-4 Torr, the partial pressure of xenon fluoride is, 1 × 10 ^over 5 Torr~2 × 10 ^-4 T
The orr range is preferred. Note that even in the process of forming such a fluoride thin film, a small amount of xenon atoms may be trapped in the film. However, since xenon atoms are rare gases and have very low reactivity,
Has little effect on increasing film loss.

As described above, in the fluoride thin film formed by the manufacturing method of the second embodiment, a film formed by a normal ion beam assist method in which xenon fluoride gas is not scattered in the vacuum chamber 1 The film loss can be reduced in a short wavelength region from an ultraviolet region having a wavelength λ = 400 nm or less to a vacuum ultraviolet region, as compared with the case of (1).
As the vapor deposition material 3 composed of a fluorine compound, for example, AlF ₃ , BaF ₂ , CaF ₂ , Na ₅ Al ₃ F ₁₄ , Na ₃ A
_{lF 6, GdF 3, PbF 2} , LaF 3, LiF, Mg
F ₂ , NdF ₃ , NaF, YbF ₃ , YF _{3 and the} like can be used.

In the above-described second embodiment, an example in which only XeF ₂ is used as xenon fluoride has been described.
Xenon fluoride mixed with XeF ₂ and XeF ₄ , XeF
Even in the case of using xenon fluoride consisting only of F _4, a fluoride thin film with reduced film loss can be formed in a short wavelength region of wavelength λ = 400 nm or less. (Modification of Second Embodiment) Next, a modification of the second embodiment will be described with reference to FIG. It should be noted that modifications of the first embodiment also correspond to claims 1, 4, and 6.

FIG. 5 is a schematic view of a vacuum deposition apparatus 40 used in a method for manufacturing a fluoride thin film according to a modification of the second embodiment. This vacuum deposition apparatus 40 also forms a film by an ion beam assist method. The vacuum vapor deposition device 40 shown in FIG. 5 has the same configuration as the vacuum vapor deposition device 30 shown in FIG. 4 except that the gasification device 8 of xenon fluoride (XeF ₂ ) is mounted outside the vacuum chamber 1. In the vacuum chamber 1, a vapor deposition source (resistance heating boat) 2 for storing a vapor deposition material 3 which is a fluorine compound, and a substrate holder 6 for holding a substrate 5 and capable of rotating and revolving.
And an ion gun 9 connected to the ion introduction tube 9a.

As shown in FIG. 5, the gasifier 8 of this modification is connected to a side wall (left side in FIG. 5) of the vacuum chamber 1 via a gas supply pipe 41. The gasifier 8 and the gas supply pipe 41 correspond to the gas scattering part of claim 6. In the middle of the gas supply pipe 41, a flow control valve 42 for controlling the flow rate of the xenon fluoride gas introduced from the gasifier 8 into the vacuum chamber 1 is provided.

Further, a pressure controller 43 is connected to the flow regulating valve 42. The pressure controller 43 is connected to a pressure gauge 44 for detecting a gas pressure in the vacuum chamber 1. Thereby, the flow rate of the xenon fluoride gas into the vacuum chamber 1 can be adjusted based on the gas pressure in the vacuum chamber 1. In the vacuum vapor deposition apparatus 40 configured as described above, the vapor deposition material 3 placed on the vapor deposition source 2 is heated and evaporated to be scattered toward the substrate 5 (about 200 ° C. to 400 ° C.), and is pulled out from the ion gun 9. and when forming the ion beam is irradiated toward the substrate 5, from the gasifier 8 attached to the outside of the vacuum chamber 1, a vacuum chamber 1 (5 × 10 ^over 6 Torr~5 × 10 ^-7 Tor
Xenon fluoride gas is introduced into r).

At this time, the set temperature of the temperature control mechanism 13 provided in the gasifier 8 is approximately 100 ° C. to 130 ° C.
° C is preferable, and the temperature control mechanism 13 and the flow control valve 42
Thereby, the partial pressure of the xenon fluoride gas in the vacuum chamber 1 can be adjusted to an arbitrary value. In this case, the partial pressure of xenon fluoride is 1 × 10 −5 Torr to 2 × 10 ⁵ Torr.
^-4 Torr is preferred.

If necessary, constant temperature control for keeping the temperature of xenon fluoride constant is also performed. In this case, the preferable partial pressure range of xenon fluoride is also 1 × 10 ⁻⁵ Torr.
２2 × 10 ⁻⁴ Torr. The total pressure during the film formation process is preferably 1 × 10 ⁻⁵ Torr in any case.
^-3 × 10 ⁻⁴ Torr.

Part of the xenon fluoride (XeF ₂ ) gas sublimated in the gasifier 8 and scattered in the vacuum chamber 1 is dissociated in the vacuum atmosphere and in the ion beam irradiation range. And xenon and fluorine are radicals,
It is in the state of ions and atoms. Since these fluorines have high reactivity, the fluorine-deficient vapor deposition material is scattered from the vapor deposition source by heating on the vapor deposition source (resistance heating boat) and the fluorine deficiency generated in the film deposition process, or the film is formed by the ion assist method. In this case, it is possible to compensate for fluorine deficiency caused by selectively sputtering fluorine from the thin film being formed.

Therefore, even the fluoride thin film formed by the manufacturing method of the modification of the second embodiment is compared with a film formed by a normal ion beam assist method in which xenon fluoride gas is not scattered in the vacuum chamber 1. Thus, the film loss can be reduced in a short wavelength region from the ultraviolet region having a wavelength λ = 400 nm or less to the vacuum ultraviolet region. Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIG. The third embodiment corresponds to claims 2 to 4, and claim 7.

FIG. 6 is a schematic view of a sputtering apparatus 50 used in the method of manufacturing a fluoride thin film according to the third embodiment. The sputtering apparatus 50 forms a film by dual ion beam sputtering, which is one of the sputtering methods. In a vacuum chamber 51 (film formation chamber) of the sputtering apparatus 50 shown in FIG.
Targets 52, 5 made of metal or fluorine compound
And a rotatable target holder 53 that holds the substrate 54 and is rotatable while holding the substrate 54.

Further, on the side wall (left side in FIG. 6) of the vacuum chamber 51 of the sputtering apparatus 50, an ion gun 56 for performing ion beam sputtering is attached to the target 52. The ion gun 56 is connected to a xenon fluoride (XeF ₂ ) gasifier 8 via a gas supply pipe 57. The gasifier 8, the gas supply pipe 57, and the ion gun 56 correspond to a gas introduction unit according to claim 7.

A flow control valve 59 is provided in the gas supply pipe 57 to control the flow rate of xenon fluoride gas supplied from the gasifier 8 to the ion gun 56. Further, a pressure controller 63 is connected to the flow control valve 59. The pressure controller 63 is connected to a pressure gauge 64 for detecting a gas pressure in the vacuum chamber 51. Thus, the flow rate of xenon fluoride gas to the ion gun 56 can be adjusted based on the gas pressure in the vacuum chamber 51.

Further, another ion gun 61 for performing ion beam assist is mounted on the side wall (the right side in FIG. 5) of the vacuum chamber 51 of the sputtering apparatus 50 toward the substrate 54. At the end of the gas supply pipe 93 of the ion gun 61, there are provided a flow control valve, a gasifier, and a rare gas gas cylinder (all not shown) similar to those of the ion gun 56 described above. Alternatively, a mixed gas of these gases is supplied to the ion gun 61, and an ion beam of these gases is irradiated toward the substrate 54.

[0068] The irradiation energy of the ion beam irradiated from the ion gun 61, in order to minimize the film loss, about 1μA / cm ² ~7μA / cm ² is preferred. In addition, cooling water is circulated through the rotary target holder 53 and the substrate holder 55 disposed in the vacuum chamber 51, and the temperature of the target 52 and the substrate 54 is stabilized so as not to rise.

Since the target 52 is cooled by the cooling water, the material of the target 52 does not evaporate by heating, unlike the case of film formation by the vacuum evaporation method. In addition, a vacuum pump (not shown) is connected to the vacuum chamber 51 of the sputtering device 50 so that the gas can be exhausted from an exhaust port 62. Hereinafter, a method for manufacturing a fluoride thin film according to the third embodiment will be described.

Prior to film formation, the film is transparent and resistant to ultraviolet rays.
Prepare an environmentally friendly quartz glass substrate 54 and perform ultrasonic cleaning
After cleaning the substrate by
It is set on the provided substrate holder 55. Also, vacuum
5 × 10 inside chamber 51 ^-6Vacuum to below Torr
Be careful.

During film formation, the gas gun 8 sends the ion gun 56
, A xenon fluoride gas is supplied at a predetermined flow rate. Then, ions and atoms of the xenon fluoride gas are extracted from the ion source 56 as a sputtering gas, accelerated, and accelerated to form the target 5 held by the target holder 53.
Shock 2 As a result, the sputtered particles hit from the target 52 scatter toward the substrate 54.

Further, during the film formation, the ion beam extracted from the ion gun 61 is irradiated toward the substrate 54 to perform the ion beam assist. Thus, in the sputtering device 50, a thin film is formed on the substrate 54 by dual ion beam sputtering. At this time, xenon fluoride (X
Fluorine radicals, ions, atoms and the like are scattered in the vacuum chamber 51 by ions and atoms of the eF ₂ ) gas.

Further, part of the xenon fluoride gas is as follows:
It is dissociated even in the ion beam irradiation range, and xenon and fluorine become radicals, ions, atoms, and the like. Since these fluorines have high reactivity, a process is selected from the process in which sputtering particles having fluorine deficiency due to sputtering are scattered toward the substrate 54, the fluorine deficiency generated in the film formation process, or the thin film being formed by ion beam assist. Fluorine deficiency generated by sputtered fluorine can be compensated.

[0074] The partial pressure is preferably in a range of from 1 × 10 ^over 5 Torr~2 × 10 ^-4 Torr of xenon fluoride in the film formation process, the total pressure 1 × 10 ^over 5 Torr~6 × 10 ^-4 Torr
Is preferable. As described above, xenon fluoride gas is more dissociated by entering the ion beam irradiation range than in a vacuum atmosphere, and more xenon and fluorine are in a state of radicals, ions, atoms, and the like.
The effect of supplementing fluorine deficiency is great.

In the process of forming the fluoride thin film in the third embodiment, a small amount of xenon atoms may be trapped in the film. However, xenon atoms are rare gases and have very low reactivity, so that they hardly affect the increase in film loss. As described above, in a fluoride thin film formed by the manufacturing method of the third embodiment, only a rare gas such as argon or xenon is introduced as a sputtering gas so that xenon fluoride gas is not scattered in the vacuum chamber 51. Film loss can be reduced in a short wavelength region from an ultraviolet region having a wavelength λ = 400 nm or less to a vacuum ultraviolet region, as compared with a film formed by the sputtering method described above.

Normally, in the sputtering process, a heavy gas such as a rare gas such as argon (Ar) or xenon is used as a sputtering gas. This is because the heavier the gas used as the sputtering gas, the higher the efficiency of the kinetic energy transition process in sputtering. In the third embodiment described above, like the rare gas,
Since heavy xenon fluoride is used as the sputtering gas, efficient sputtering can be performed, and the selectively sputtered fluorine can be supplemented.

In the third embodiment described above, an example was described in which only xenon fluoride gas (XeF ₂ ) was used as the sputtering gas. However, xenon fluoride gas and a rare gas (such as argon or xenon) were used as the sputtering gas. And a mixed gas of these. in this case,
What is necessary is just to connect not only the gasifier 8 of xenon fluoride but also the gas cylinder of the rare gas to the ion gun 56 via the gas supply pipe 57. The rare gas gas cylinder can be attached to the side wall of the vacuum chamber 11 via another gas supply pipe without being connected to the ion gun 56.

Further, as in a sputtering apparatus 60 shown in FIG.
Is connected and only a noble gas (such as argon or xenon) is used as a sputtering gas in a vacuum chamber 51 as in the case of the vacuum evaporation apparatus 20 shown in FIG.
A gasifier 8 is attached to the side wall of the gas supply pipe 66 via a gas supply pipe 66 and a flow control valve 67, and a xenon fluoride (XeF ₂ ) gas may be introduced from the gasifier 8 into the vacuum chamber 51. 3). In this case, in order to maintain the effect of compensating for the fluorine deficiency, the partial pressure of xenon fluoride gas is set to 1
× 10 ^over 5 Torr~2 × 10 ^-4 Torr range, it is preferable that the total pressure in the range of 1 × 10 ^over 5 Torr~6 × 10 ^-4 Torr.

Also in this case, a part of the xenon fluoride gas sublimated in the gasifier 8 and scattered in the vacuum chamber 51 is dissociated in a vacuum atmosphere, and xenon and fluorine are converted into radicals, ions, atoms and the like. State. Since these fluorines have high reactivity, a process in which sputtering particles having fluorine deficiency by sputtering are scattered toward the substrate 54, and a fluorine deficiency generated in a film forming process, or a film formed by an ion beam assist method, The fluorine deficiency generated by the selective sputtering of fluorine from the thin film being formed can be compensated.

At the end of the gas supply pipe 93 of the ion beam assisted ion gun 61, a flow control valve, a gasifier, and a rare gas gas cylinder (all not shown) are provided, and xenon fluoride or rare gas is used. Gas or a mixed gas thereof is supplied to the ion gun 61, and an ion beam of these gases is irradiated toward the substrate 54. In FIG. 7, the gasification device 8 and the gas supply pipe 66 correspond to a gas introduction unit according to claim 7.

As the target 52 made of a fluorine compound, for example, AlF ₃ , BaF ₂ , CaF ₂ , N
_{a 5 Al 3 F 14, Na} 3 AlF 6, GdF 3, PbF 2, La
F ₃ , LiF, MgF ₂ , NdF ₃ , NaF, YbF ₃ , Y
Or the like can be used F _3. As the target 52 made of a metal, for example, aluminum (Al), barium (Ba), calcium (Ca), sodium (Na),
Gadolinium (Gd), lead (Pb), lanthanum (La), lithium (Li), magnesium (Mg), neodymium (N
d), yttrium (Yb), yttrium (Y) and the like can be used.

In the third embodiment described above, an example in which only XeF ₂ is used as xenon fluoride has been described.
Xenon fluoride mixed with XeF ₂ and XeF ₄ , XeF
Even in the case of using xenon fluoride consisting only of F _4, a fluoride thin film with reduced film loss can be formed in a short wavelength region of wavelength λ = 400 nm or less. In the sputtering process in the sputtering device 50 described above,
As in the vacuum deposition process in the vacuum deposition apparatus 10,
In order not to raise the surface temperature of the target 52 to a high temperature,
The target 52 having a relatively large area can be placed in contact with the substrate 54 without the influence of the radiant heat from the target 52.

Therefore, the same effect can be obtained even if the number of atoms and molecules per unit area of the target per unit time in the sputtering process is much smaller than that of the evaporation source. (Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIG. Note that the fourth embodiment corresponds to claims 5 and 8.

FIG. 8 shows a high-frequency ion plating apparatus 70 used in the method of manufacturing a fluoride thin film according to the fourth embodiment.
FIG. In a vacuum chamber 71 (film formation chamber) of the high-frequency ion plating apparatus 70 shown in FIG. 8, a deposition source 73 for placing a deposition material 72 made of a metal or a fluorine compound, and a substrate holder 75 for holding a substrate 74
And a high frequency (RF) coil 76 which is a high frequency electrode for causing discharge.

Further, a xenon fluoride (XeF ₂ ) gasifier 8 is connected to the side wall of the vacuum chamber 71 of the high-frequency ion plating apparatus 70 via a gas supply pipe 78. The gasification device 8 and the gas supply pipe 78 correspond to the gas introduction part of claim 8.

A flow regulating valve 79 for regulating the flow of xenon fluoride gas supplied from the gasifier 8 to the vacuum chamber 71 is provided in the gas supply pipe 78. Further, a pressure controller 85 is connected to the flow control valve 79. The pressure controller 85 is connected to a pressure gauge 86 that detects a gas pressure in the vacuum chamber 71. Thus, the flow rate of the xenon fluoride gas into the vacuum chamber 71 can be adjusted based on the gas pressure in the vacuum chamber 71.

Note that a DC power supply 81 is connected to the substrate holder 75 so that a predetermined DC voltage can be applied to the substrate 74. As a result, the substrate 74 is maintained at a negative potential. A matching box 82 for impedance matching is provided at one end of the high frequency (RF) coil 76.
, And the other end is open. This allows the radio frequency (RF) coil 76
, High-frequency power of 13.56 MHz is applied efficiently with matching impedance.

The high-frequency (RF) coil 76, the matching box 82 and the high-frequency power supply 83 correspond to a plasma generating unit according to the present invention. Further, a vacuum pump (not shown) is connected to the vacuum chamber 71 of the high-frequency ion plating apparatus 70 so that the vacuum chamber 71 can be evacuated from the exhaust port 84. Hereinafter, a method for manufacturing a fluoride thin film according to the fourth embodiment will be described.

Prior to film formation, the film is transparent and resistant to ultraviolet rays.
Prepare an environmentally friendly quartz glass substrate 74 and perform ultrasonic cleaning
After cleaning the substrate by
It is set on the substrate holder 75 provided. Also, vacuum
5 × 10 inside chamber 71 ^-6Vacuum to below Torr
Be careful. Next, inside the vacuum chamber 71,
From the attached gasifier 8, xenon fluoride gas
Is introduced.

The xenon fluoride gas is turned into plasma by a high frequency (RF) coil 76 in the vacuum chamber 71. The deposition material 72 placed on the deposition source 73 is:
It is heated and evaporated and scattered toward the substrate 74. The evaporated material 72 is ionized in the plasma of the xenon fluoride gas generated in the radio frequency (RF) coil 76. Since this ionization is performed by high-frequency excitation, the efficiency is high and there is almost no increase in the substrate temperature.

Then, the ionized vapor deposition material 72
Is attracted to the substrate 74 maintained at the negative potential, and the substrate 7
A thin film is formed on 4. The pressure during film deposition is controlled by adjusting the gasifier and the flow control valve, the partial pressure of xenon difluoride gas is preferably in the range of 5 × 10 ^{over 5 Torr~1} × 10 ^-4 Torr, total pressure 8 × 10 ^over 5 Torr~1 × 10
^-4 Torr is preferable.

At this time, fluorine radicals, ions, atoms and the like are scattered in the vacuum chamber 71 by the ions and atoms of the xenon fluoride (XeF ₂ ) gas which has been turned into plasma by the high frequency (RF) coil 76. I have. Since these fluorines have high reactivity, they can compensate for the fluorine deficiency generated in the process in which the vapor-deposited material 72 deficient in fluorine is scattered by the heating in the vapor deposition source 73 and in the film formation process.

In the process of forming the fluoride thin film in the fourth embodiment, a small amount of xenon atoms may be trapped in the film. However, xenon atoms are rare gases and have very low reactivity, so that they hardly affect the increase in film loss. As described above, in the fluoride thin film formed by the manufacturing method of the fourth embodiment, only a rare gas such as argon or xenon is introduced into the vacuum chamber 71 as an introduction gas for plasma generation, and xenon fluoride Compared to a film formed by a normal high-frequency ion plating method that does not scatter gas,
The film loss can be reduced in a short wavelength region from an ultraviolet region having a wavelength λ = 400 nm or less to a vacuum ultraviolet region.

The vapor deposition material 72 made of a fluorine compound
For example, AlF ₃ , BaF ₂ , CaF ₂ , Na ₅ A
l ₃ F ₁₄ , Na ₃ AlF ₆ , GdF ₃ , PbF ₂ , LaF ₃ ,
LiF, MgF ₂ , NdF ₃ , NaF, YbF ₃ , YF _{3 and the} like can be used. As the vapor deposition material 72 made of metal, for example, Al, Ba, Ca, Na, Gd,
Pb, La, Li, Mg, Nd, Yb, Y and the like can be used.

In the fourth embodiment, xenon fluoride (XeF) is used as an introduction gas for plasma generation.
₂ ) Although only the gas was used, a mixed gas of this xenon fluoride gas and a rare gas (eg, argon or xenon) can also be used. In this case, the gas supply pipe 78 may be connected not only with the xenon fluoride gasifier 8 but also with a rare gas introduction system (not shown). The rare gas supply system may be attached to the side wall of the vacuum chamber 11 via another gas supply pipe without being commonly connected to the xenon fluoride gas supply pipe 78.

In the above-described fourth embodiment, an example in which only XeF ₂ is used as xenon fluoride has been described.
Xenon fluoride mixed with XeF ₂ and XeF ₄ , XeF
Even in the case of using xenon fluoride consisting only of F _4, a fluoride thin film with reduced film loss can be formed in a short wavelength region of wavelength λ = 400 nm or less.

[0097]

Next, an embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG.

FIG. 9 shows a 45 ° laser mirror 90 manufactured by the method of manufacturing a fluoride thin film according to the present invention. The laser mirror 90 has a center wavelength of λ = 193.
and a low refractive index layer 91 made of magnesium fluoride (MgF ₂ ) having an optical thickness of λ / 4 on the quartz glass substrate 5 and lanthanum fluoride (LaF) having an optical thickness of λ / 4. _This is a 41-layer structure in which alternating layers of the high refractive index layers 92 made of ₃ ) are laminated.

Hereinafter, a specific method of manufacturing the 45 ° laser mirror 90 of the example using the vacuum deposition apparatus 30 (FIG. 4) used in the method of manufacturing a fluoride thin film of the second embodiment will be described. . First, a quartz glass substrate 5 is prepared, subjected to ultrasonic cleaning, and then set on a substrate holder 6 provided in the vacuum chamber 1. Then, the substrate 5 is heated to about 300 ° C. The inside of the vacuum chamber 1 is evacuated to 1 × 10 ⁻⁶ Torr.

The evaporation material 3 made of magnesium fluoride (MgF ₂ ) placed on the evaporation source (resistance heating boat) 2 is evaporated and scattered toward the substrate 5, and the energy extracted from the ion gun 9 is 4 μA / cm. ^{The second} ion beam is irradiated toward the substrate 5. Thus, the low refractive index layer 91 made of the magnesium fluoride (MgF ₂ ) film was formed on the substrate 5 by using the ion beam assist method.

At the same time, the temperature is set to 130 ° C. by the temperature control mechanism 13 provided in the container 12 of the xenon fluoride gasifier 4, and xenon fluoride (XeF ₂ ) is gasified and directed to the substrate 5. Splashed. Similarly, a high-refractive-index layer 92 made of a lanthanum fluoride (LaF ₃ ) film was formed by an ion beam assist method while scattering xenon fluoride (XeF ₂ ) gas.

By repeating these steps, 41 alternating layers were formed. FIG. 10 shows a spectral characteristic diagram of the laser mirror 90 manufactured in the example at an incident angle θ = 45 °.

For comparison, when the center wavelength was set to λ = 193 nm using a conventional ion beam assist method (forming a film without scattering xenon fluoride gas), an optical beam was formed on a quartz glass substrate. Forty-one alternating layers of a low refractive index layer made of magnesium fluoride (MgF ₂ ) having a film thickness of λ / 4 and a high refractive index layer made of lanthanum fluoride (LaF ₃ ) having an optical film thickness of λ / 4 were formed.

FIG. 11 shows a spectral characteristic diagram of the laser mirror manufactured in this comparative example at an incident angle θ = 45 °. The laser mirror 90 manufactured in the embodiment has λ = 193n
The reflectivity at m is about 98% (FIG. 10), but the laser mirror manufactured in the comparative example has a reflectivity at λ = 193 nm of about 93% (FIG. 11).

The laser mirror 90 manufactured in the embodiment clearly has smaller film loss and better reflectivity characteristics.

[0106]

As described above, claims 1 to 8 are described.
According to the invention described in (1), since the xenon fluoride gas is scattered, even when fluorine deficiency occurs due to resistance heating, heating evaporation with an electron gun or sputtering, the fluorine deficiency can be efficiently compensated.

Therefore, it is possible to manufacture a high-quality fluoride thin film with small light loss even in a short wavelength region of a wavelength of 400 nm or less, and a sufficient transmittance even when an optical system composed of several tens of lenses is used. Can be obtained. In addition, since xenon fluoride gas is relatively stable, harmless, and easy to handle, the method for producing a fluoride thin film according to the present invention using the gas has safety, convenience, and environmental friendliness.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a vacuum evaporation apparatus 10 according to a first embodiment.

FIG. 2 is a schematic cross-sectional view of a xenon fluoride gasifier used in the vacuum evaporation apparatus 10.

FIG. 3 is a schematic sectional view of a vacuum evaporation apparatus 20 according to a modification of the first embodiment.

FIG. 4 is a schematic sectional view of a vacuum evaporation apparatus 30 using an ion beam assist method according to a second embodiment.

FIG. 5 is a schematic sectional view of a vacuum evaporation apparatus 40 according to a modification of the second embodiment.

FIG. 6 is a schematic sectional view of a sputtering apparatus 50 using a dual ion beam sputtering method according to a third embodiment.

FIG. 7 is a schematic sectional view showing a configuration of a sputtering apparatus 60.

FIG. 8 is a schematic sectional view of a high-frequency ion plating apparatus 70 according to a fourth embodiment.

FIG. 9 is a schematic sectional view of a laser mirror 90 manufactured in the embodiment.

FIG. 10 is a spectral characteristic diagram at an incident angle θ = 45 ° of the laser mirror 90 manufactured in the example.

FIG. 11 is a spectral characteristic diagram at an incident angle θ = 45 ° of a laser mirror manufactured in a comparative example.

[Explanation of symbols]

1,51,71 Vacuum chamber 2,73 Evaporation source 3,72 Evaporation material 4,8 Gasifier 5,54,74 Substrate 6,55,75 Substrate holder 7,62,84 Exhaust port 9,56,61 Ion gun 9a Ion introduction tube 10, 20, 30, 40 Vacuum vapor deposition device 11 Xenon fluoride 12 Container 13 Temperature control mechanism 21, 41, 57, 66, 78, 93 Gas supply tube 22, 42, 59, 67, 79 Flow control valve 50, 60 Sputtering apparatus 52 Target 53 Target holder 70 Ion plating apparatus 76 High frequency (RF) coil 81 DC power supply 82 Matching box 83 High frequency power supply 90 Laser mirror 91 Low refractive index layer (MgF ₂ ) 92 High refractive index layer (LaF ₃₎ )

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G02B 5/28 G02B 1/10 Z

Claims (8)

[Claims] 1. A method of manufacturing a fluoride thin film, wherein a fluorine compound is scattered from an evaporation source in a vacuum atmosphere to form a film on a substrate, wherein xenon fluoride gas is scattered during the film formation. A method for producing a fluoride thin film. 2. A method for forming a thin film of a fluoride on a substrate by sputtering, wherein a target made of a metal or a fluorine compound is disposed, and xenon fluoride gas or a mixed gas of xenon fluoride gas and a rare gas is used. As a sputtering gas, and bombarding the target with the sputtering gas to scatter the metal or fluorine compound to form a film. 3. When forming a fluoride thin film on a substrate using a sputtering method, a target made of a metal or a fluorine compound is arranged, a rare gas is introduced as a sputtering gas, and the target is bombarded with the rare gas. Forming a film by scattering the metal or the fluorine compound; and introducing xenon fluoride gas or a mixed gas of xenon fluoride gas and a rare gas during the film formation. Manufacturing method of thin film. 4. The method of manufacturing a fluoride thin film according to claim 1, wherein the surface of the fluoride thin film being formed is irradiated with an ion beam during the film formation. A method for producing a fluoride thin film. 5. When depositing a fluoride thin film on a substrate using an ion plating method, an evaporation source for scattering a metal or a fluorine compound is arranged, and during the deposition, xenon fluoride gas or fluorine gas is used. A method for producing a fluoride thin film, comprising: introducing a mixed gas of a xenon fluoride gas and a rare gas to generate plasma; and ionizing a metal or a fluorine compound scattered from the evaporation source in the plasma. 6. A film formation chamber in which an evaporation source for scattering a fluorine compound as a deposition material and a substrate holder for holding a substrate are disposed, an exhaust unit for exhausting the film formation chamber, and the film formation chamber. And a gas scattering portion for scattering xenon fluoride gas. 7. A target holder for holding a sputtering target made of a metal or a fluorine compound,
A film formation chamber in which a substrate holder for holding the substrate is disposed, a power application unit that applies a predetermined power to a target held by the target holder, and an exhaust unit that exhausts the film formation chamber. A gas introduction unit for introducing, as a sputtering gas, a xenon fluoride gas or a mixed gas of a xenon fluoride gas and a rare gas into the film formation chamber, wherein a fluoride thin film manufacturing apparatus is provided. 8. A film forming chamber in which an evaporation source for scattering a metal or a fluorine compound as an evaporation material and a substrate holder for holding a substrate are provided. A power application unit that applies power, an exhaust unit that exhausts the inside of the film formation chamber, and a gas introduction unit that introduces xenon fluoride gas or a mixed gas of xenon fluoride gas and a rare gas into the film formation chamber. An apparatus for producing a fluoride thin film, comprising: a plasma generation unit that generates plasma of a gas introduced by the gas introduction unit between the evaporation source and the substrate.