JPH05230644A - Ceramics rotary cathode target and its manufacture - Google Patents

Abstract

PURPOSE:To provide a ceramics rotary cathode target by which an oxide transparent thin film having a low refractive index and high durability can be sputtered at a high film forming rate. CONSTITUTION:Ceramics powder 4 essentially consisting of at least one kind among Zr, Ti, Ta, Hf, Mo, W, Nb, Sn, La, In and Cr (hereinafter referred to as metal M) and Si and in which the total of the atomic ratio of the metal M to Si is regulated to (4:96) to (35:65) is filled into the circumference of the outer surface of a cylindrical target holder 2, and hot isotropic pressing is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic rotating cathode target used for forming a ceramic film, particularly an oxide transparent thin film having a low refractive index by sputtering, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a thin film is formed on a transparent substrate such as glass or plastic to add an optical function to a mirror, a heat ray reflecting glass, a low radiation glass, an interference filter, an antireflection coat for a camera lens or a spectacle lens. Etc. In a normal mirror, Ag is formed by an electroless plating method, and Al or Cr is formed by a vacuum deposition method, a sputtering method, or the like. Among these, the Cr film is relatively strong and is therefore used as a part of a surface mirror having an exposed coated surface.

Titanium oxide, tin oxide and the like have been formed in the heat ray reflective glass by a spray method, a CVD method or a dipping method. Recently, a metal film, a nitride film, tin-doped indium oxide (ITO) or the like formed on the glass surface by a sputtering method has come to be used as a heat ray reflective glass. In the sputtering method, the film thickness can be easily controlled, a plurality of films can be continuously formed, and the transmittance, the reflectance, the color tone and the like can be designed in combination with the transparent oxide film. For this reason, demand is increasing for buildings that emphasize design.

Low-emissivity glass that reflects radiant heat from an indoor heater or wall to the indoor side is a ZnO / Ag / ZnO three-layer system in which silver is sandwiched by zinc oxide or ZnO / Ag / ZnO / It has a structure such as a five-layer system of Ag / ZnO (see Japanese Patent Laid-Open No. 63-239043) and is used in the form of double-layer glass or laminated glass. In recent years, it has been remarkably popularized in cold regions of Europe. For the antireflection coating of a lens or the like, a high refractive index film such as titanium oxide or zirconium oxide and a low refractive index film such as silicon oxide or magnesium fluoride are alternately laminated. Usually, a vacuum vapor deposition method is used, and the substrate is heated during film formation to improve scratch resistance.

A surface mirror, a single-plate heat ray-reflecting glass, and an antireflection coat such as a lens are used with the coated film exposed to the air. Therefore, it must have excellent chemical stability and abrasion resistance. On the other hand, even low-reflection glass may be defective due to scratches during transportation or handling before it becomes a double glazing or laminated glass. Therefore, a protective film that is stable and has excellent abrasion resistance or an optical thin film that also serves as a protective film is desired.

To improve durability, a chemically stable and transparent oxide film is usually provided on the air side. These oxide films include titanium oxide, tin oxide, tantalum oxide, zirconium oxide, silicon oxide and the like, and typical films having a low refractive index include magnesium fluoride and the like, which are selected according to the required performance. Has been used. Titanium oxide, tin oxide, tantalum oxide, and zirconium oxide have a high refractive index, while silicon oxide and magnesium fluoride have a low refractive index.

However, it is difficult to form these films on a substrate having a large area, and it has not been possible to deal with a place where a large area is required to be formed, such as glass for buildings and glass for automobiles. The direct current sputtering method is most suitable for large area film formation, but there is no suitable target material that provides a transparent thin film having a low refractive index, and it is desirable to use the direct current sputtering method capable of large area film formation. Could not be obtained.

For example, in order to form a silicon oxide thin film by a direct current sputtering method, a method of forming a silicon dioxide thin film by reactive sputtering of a conductive Si target in an atmosphere containing oxygen can be considered. As a result, the surface was oxidized and the conductivity was lowered, so that the sputtering could not be sustained stably. Further, the formed silicon dioxide thin film is weak against alkalinity and cannot endure long-term immersion. Therefore, the present applicant has filed Japanese Patent Laid-Open No. 3-177
At 568, an amorphous oxide thin film and a target having a high durability, a low refractive index, and a wide degree of freedom in optical design were proposed.

[0009]

On the other hand, a planar target for sputtering is formed by mixing raw materials of an inorganic compound,
It is created through processing and bonding and a long process for forming a shape suitable for a firing and sputtering device. Among these, the steps such as molding, firing, processing, and bonding do not require a large jig device when the target is small, but the above jig device becomes large for a large-scale target for a production machine, and ceramics are also used for bonding. When joining the target to the target holder metal plate, it is made by dividing and processing and joining, but a large-scale device, using a large amount of expensive In solder, etc.
It takes labor and cost.

Further, in the case of sputtering large-area glass for construction, a high sputtering power is applied to increase the film forming speed in order to improve productivity, but in this case, the cooling of the target limits the film forming speed. There are problems such as cracking and peeling.

A new type of magnetron type rotating cathode target which is improved in these points is known (see Japanese Patent Publication No. 58-500174). This is because the magnetic field generating means is installed inside the cylindrical target, and the sputtering is performed while rotating the target while cooling from the inside of the target, so that a larger power can be input per unit area than the planar target. Therefore, high-speed film formation is possible. Such a target is a cylindrical rotating cathode which is mostly made of a metal or alloy to be sputtered, and when the material to be sputtered is a soft or brittle metal or alloy, it is manufactured on a cylindrical target holder.

However, in the case of a metal target, it is possible to coat a multilayer film of oxides, nitrides, carbides, etc. in various sputtering atmospheres, but the coating film is damaged by a different atmosphere and the desired composition cannot be obtained. Further, a low-melting-point metal target has a drawback that it melts when too much power is applied, and a ceramic target is desired.

A method for producing a sputter target by thermal spraying has been proposed in Japanese Patent Laid-Open No. 60-181270, but the thermal spray film cannot be made thick due to the large difference in thermal expansion between ceramics and metal, and the adhesiveness due to heat shock during use. Is deteriorated and peeling occurs. There is also a method of manufacturing a ceramics sintered body into a cylindrical shape and joining it to a target holder metal with In metal, but it is difficult to manufacture and costly.

The applicant of the present invention, in Japanese Patent Application No. 3-242558, roughens the outer surface of a cylindrical target holder, and then,
A layer made of a metal or an alloy having a coefficient of thermal expansion intermediate between the coefficient of thermal expansion of a ceramic layer to be formed later and the coefficient of thermal expansion of the target holder is formed as an undercoat, and then the ceramic powder is semi-heated in a hot gas. A method for manufacturing a ceramics rotating cathode, comprising forming a ceramics layer as a target to be sputtered by transporting and adhering on the undercoat by this gas while being in a molten state,
r, Ti, Ta, Hf, Mo, W, Nb, Sn, La,
At least one of In and Cr and Si are main components, and the total amount of metal M and Si are in an atomic ratio of 4:96 to 35:
A method of manufacturing a ceramic rotating cathode target, characterized in that it is a powder having a ratio of 65, was proposed.

However, when the difference in the coefficient of thermal expansion between the ceramic layer and the target holder is large, problems such as cracks in the ceramic layer coating during plasma spraying or sputtering, and the chemical composition of the ceramic layer in the atmospheric plasma. Because of thermal spraying, there is a problem that it changes due to oxidation or the like.

As a result of earnest research in view of the above-mentioned object, the present invention further improves the adhesion between the target holder and the ceramics layer, and allows the ceramics rotating cathode to be sputtered uniformly and stably without changing the chemical composition of the ceramics layer. It proposes a target manufacturing method.

[0017]

The present invention has been made to solve the above-mentioned problems, and the outer surface of a cylindrical target holder is roughened, and the coefficient of thermal expansion of a ceramic layer to be formed later is formed on the outer surface of the cylindrical target holder. And at least one of a layer made of a metal or an alloy having a thermal expansion coefficient intermediate between those of the target holder and a layer of a metal or an alloy having a thermal expansion coefficient close to that of the ceramic layer. Is formed as an undercoat by plasma spraying, and then ceramic powder or a molded body of such powder is placed around the outer surface of such a cylindrical target holder, and hot isostatic pressing is performed to produce a ceramic rotating cathode target. The above-mentioned ceramic powder is Zr, Ti, Ta, Hf, Mo, W, N
At least one of b, Sn, La, In, and Cr (hereinafter referred to as metal M) and Si are main components, and the total amount of metal M and Si are in an atomic ratio of 4:96 to 35:65. Provided is a method for manufacturing a ceramic rotating cathode target, which is a powder having

Further, according to the present invention, a ceramic layer serving as a target to be sputtered is formed on the outer surface of a cylindrical target holder, and the coefficient of thermal expansion between the ceramic layer and the target holder is intermediate. At least one layer of a layer made of a metal or an alloy having a coefficient of thermal expansion and a layer made of a metal or an alloy having a coefficient of thermal expansion close to that of the ceramics layer,
A ceramic rotating cathode target formed as an undercoat between the ceramic layer and the target holder, wherein the ceramic layer comprises:
Zr, Ti, Ta, Hf, Mo, W, Nb, Sn, L
At least one of a, In, and Cr (hereinafter referred to as a metal M) and Si as a main component, and having a total amount of the metal M and Si in an atomic ratio of 4:96 to 35:65. Also provided is a ceramic rotating cathode target.

The method of the present invention is basically a method for hot isostatic pressing (hereinafter, referred to as "ceramic powder").
It is sintered and bonded to a target holder by HIP) to directly form a ceramic layer as a target. By this, the process of packing powder in a conventional mold and press-molding, the process of sintering it in an electric furnace,
Alternatively, a step of sintering by hot pressing, a step of processing and modifying into an appropriate shape, and a step of joining ceramics and a holder are not required.

The method of the present invention comprises a step of obtaining a raw material powder, a surface treatment step for closely bonding the outer surface of a cylindrical target holder to a ceramic layer, and a step of sintering and bonding by HIP processing. ing. The ceramic powder used in the present invention is produced by utilizing chemical synthesis or solid-phase reaction, especially in the case of a complex compound that is not easily available. This powder can be used by pulverizing it, granulating it, and flowing it into the HIP-treated capsule to make it into a secondary particle size that facilitates vibration filling.

In the present invention, the ceramic layer is Z
r, Ti, Ta, Hf, Mo, W, Nb, Sn, La,
At least one of In and Cr and Si are main components, and the total amount of metal M and Si are in an atomic ratio of 4:96 to 35:
It has a ratio of 65. In particular, 4: 96-1
The ratio of 5:85 is preferable because the refractive index of the formed thin film is as low as 1.6 or less. When the content of the metal M such as Zr is less than 4 atom% in the total amount with Si,
In an oxidizing atmosphere, it is difficult to stably sputter the surface of the target due to surface oxidation, and the formed thin film (for example, an oxide film of Zr and Si) has poor alkali resistance. If the content of the metal M such as Zr is more than 35 atom% in the total amount with Si, the refractive index of the formed thin film becomes high, which is not preferable.

The ceramic powder used in the present invention can be produced, for example, by the following method. That is, metals such as Zr M, Si, ZrSi ₂ , ZrO ₂ (Y ₂ O ₃ , Ca
O, MgO, etc. are added in the range of 3 to 8 mol% of stabilized or partially stabilized ZrO ₂ ), SiO ₂ etc. powder or mixed powder, and non-oxide target, if necessary. By mixing a mixture of carbon powders for reducing oxides in a high temperature non-oxidizing atmosphere furnace utilizing chemical synthesis or solid-state reaction, a lumpy single-type or complex-type powder can be obtained.

A binder is added to a powder obtained by crushing the powder to an average particle size of 1 μm or less, and made into a slurry, and the powder is granulated into secondary particles by a spray dryer. The granulated powder preferably has a particle size of 150 μm or less, and particularly, an average particle size of about 80 μm is suitable and a packed compact having good fluidity and packing density can be obtained.

Fe, A is added to the above-mentioned ceramic powder.
The total content of l, Mg, Y, Mn, and H may be 3 wt% or less. Since C (carbon) disappears as CO ₂ during film formation, 20 wt% or less of C may be contained. .. Further, it may contain Cu, V, Co, Rh, Ir and the like in the amount of impurities.

As the cylindrical target holder, stainless steel, copper, or Ti or Mo having a thermal expansion coefficient similar to that of a ceramic layer can be used. Prior to the HIP treatment of the ceramic powder, its outer surface is made of Al ₂ O ₃ or Roughening by sandblasting using SiC abrasive grains is also optimal for improving adhesion. Alternatively, prior to the HIP treatment of the ceramic powder, the outer surface of the ceramic powder is processed into a V-groove shape or a screw shape, and then sandblasted with Al ₂ O ₃ or SiC abrasive grains to roughen it so that the adhesion is improved. Is also preferable.

In the cylindrical target holder whose outer surface is roughened, in order to reduce the difference in thermal expansion between the ceramic layer and the target holder, and to increase the adhesion so as to withstand peeling due to heat shock during sputtering, It is preferable to form an undercoat. As such an undercoat, a layer made of a metal or an alloy having a thermal expansion coefficient intermediate between the thermal expansion coefficient of the target holder and the thermal expansion coefficient of the target material (hereinafter referred to as A layer) and the thermal expansion coefficient of the target material are close to each other. It is preferable that at least one layer out of layers (hereinafter, referred to as B layer) made of a metal or an alloy having a thermal expansion coefficient, and its powder are formed by plasma spraying. In particular, it is optimal to form both layers and to have a structure of target holder / A layer / B layer / target material.

Even if the undercoat is only the B layer, since the metal and the alloy have high elasticity and small brittleness, the adhesion of the target material to the target holder can be increased. The thermal expansion coefficient of the B layer is preferably a value within the range of ± 2 × 10 ⁻⁶ / ° C. of the thermal expansion coefficient of the ceramic layer.

As the material of the undercoat, Mo, T
i, Ni, Nb, Ta, W, Ni-Al, Ni-Cr,
Ni-Cr-Al, Ni-Cr-Al-Y, Ni-Co
A conductive powder such as -Cr-Al-Y can be used. The thickness of the undercoat is 30 to 100 μm, respectively
A degree is preferable.

[0029] Specifically, the undercoat material will vary depending on the thermal expansion coefficient of the ceramic layer (which can be used in the target holder, the thermal expansion coefficient such as Cu or SUS304 is 17-18 × 10 ^{- 6} / ° C.).

For example, the ceramic layer is Hf-Si.
System, Cr-Si system, Sn-Si system, Zr-Si system (Z
When Zr is smaller than r: Si (atomic ratio) = 33: 67) (coefficient of thermal expansion 5 to 6 × 10 ⁻⁶ / ° C.), the preferable thermal expansion coefficient of the undercoat A layer is 12 to 15 ×.
10 ⁻⁶ / ° C., and its material is Ni, Ni—A
1, Ni-Cr, Ni-Cr-Al, Ni-Cr-Al
-Y, Ni-Co-Cr-Al-Y, etc. are mentioned. The thermal expansion coefficient of the undercoat B layer is preferably 5-8.
× 10 ^-6 / ° C, and its material is Mo, W, T
a, Nb and the like.

Further, the ceramic layer is a Ta--Si system,
Ti-Si system (when Ti is less than Ti: Si (atomic ratio) = 33: 67), Zr-Si system (Zr: Si (atomic ratio) = 33: 67 or when Zr is more than this, Zr
(Including Si ₂ ), etc. (coefficient of thermal expansion 8 to 9 × 10 ⁻⁶ / ° C.), the preferable thermal expansion coefficient of the undercoat A layer is 1
2 to 15 × 10 ⁻⁶ / ° C., and its material is N
i, Ni-Al, Ni-Cr, Ni-Cr-Al, Ni
-Cr-Al-Y, Ni-Co-Cr-Al-Y, etc. are mentioned. The preferable thermal expansion coefficient of the undercoat B layer is 8 to 10 × 10 ⁻⁶ / ° C., and its material includes Ti, Nb and the like.

Further, the ceramic layer is made of a Ti--Si system (Ti: Si (atomic ratio) = 33: 67 or T
When i is large, TiSi ₂ is included), etc. (coefficient of thermal expansion is 10)
˜13 × 10 ⁻⁶ / ° C.), the preferable thermal expansion coefficient of the undercoat is 10 to 13 × 10 ⁻⁶ / ° C., and its material is Ni, Ni—Al, Ni—Cr, Ni—
Cr-Al, Ni-Cr-Al-Y, Ni-Co-Cr
-Al-Y etc. are mentioned. When the difference in the coefficient of thermal expansion between the ceramic layer and the target holder is small as described above, the undercoat may be a single layer. Further, among such undercoat materials, the composition ratio may be changed to provide two layers, a layer having a thermal expansion coefficient close to that of the target holder and a layer having a thermal expansion coefficient close to that of the ceramics layer.

Next, the above-mentioned target holder subjected to the undercoat treatment is placed in the HIP-treated capsule of FIG. 1, the above-mentioned ceramic granulated powder is filled, and sintering and joining are carried out by the HIP treatment.

The HIP processing capsule will be described with reference to FIG. The HIP processing capsule is composed of a bottomed stainless steel capsule 1 and a cylindrical target holder 2 arranged therein, and these are welded at predetermined positions, that is, at the center of the bottom of the bottomed stainless steel capsule 1 by welding the cylindrical target holder. Joined and fixed. This HI
The P treatment capsule is preferably steel or stainless steel,
The thickness of the capsule is preferably 4 mm or less.

Further, the HIP-treated capsule 1 suppresses a reaction in sintering of the ceramic layer filled in the capsule in the HIP treatment step and facilitates release from the ceramic layer after the HIP treatment. For HIP
Alumina fiber paper (0.5 mm to 1 mm thick) or a sheet may be attached to the inner surface of the treated stainless steel capsule 1.

The ceramic powder is filled in the gap between the stainless capsule 1 and the cylindrical target holder 2. Alternatively, by using the cylindrical target holder 2 which has been surface-treated in advance, the cylindrical target holder 2 is placed in a CIP (cold isostatic pressing) molding rubber mold, and the ceramic powder is filled in the gap between the cylindrical target holder 2 and the preliminary CIP. A molding method can also be adopted.

According to the above method, the ceramic powder filled in the HIP-processed stainless capsule or the ceramic molded body pre-CIP-molded on the cylindrical target holder device is placed in the HIP-processed capsule,
10 ^-3 Tor of this HIP processing stainless steel capsule
Seal under reduced pressure below r. This vacuum seal is 10 ^-3 Tor
This is because if it exceeds r, the gas and components adhering to the ceramic raw material powder are not sufficiently removed.

This vacuum-sealed stainless steel HIP capsule is placed in a HIP device and subjected to HIP treatment. In the HIP process, an inert gas (Ar) under high temperature and high pressure is used as a pressure medium to simultaneously sinter the ceramic powder inside the capsule and the preformed ceramic compact and join the ceramic layer and the target holder. At this time, it is desirable that the HIP treatment conditions are a temperature of 900 to 1200 ° C. and a pressure of 50 MPa or more for 1 hour or more. HIP processing condition is temperature less than 900 ° C or pressure 50
When the pressure is less than MPa, the density of the ceramic layer is low and the adhesion to the target holder is low, and when the temperature exceeds 1200 ° C., the reaction with the target holder becomes vigorous, which is not preferable.

The HIP-processed stainless steel HIP-treated capsules thus obtained are taken out from the HIP device, and the stainless steel capsules on the outer surface are peeled off to obtain a ceramic rotating cathode target. In this way, it is possible to obtain a dense ceramic rotating cathode having a ceramic layer of 2 mm or more and 10 mm or less and having high adhesion to the target holder.

The rotary cathode target thus manufactured is homogeneous without any oxidation of the target material and no change in chemical composition, and the heat conduction from the target material to the target holder and further to the cathode electrode is good, and the target holder is solid. Since it is in close contact with the target, cooling is sufficiently performed even when high sputtering power is applied to increase the film formation speed, and there is no peeling or cracking of the target due to sudden heat shock, and a large amount of power is applied per unit area. It is possible.

Further, since the erosion zone of the target is the entire surface, there is an advantage that the utilization efficiency of the target is higher than that of the planar type. Further, even if the eroded portion of the target becomes thin, it is also possible to regenerate the original state by subjecting the portion where the target material is reduced to the HIP treatment with the ceramic powder of the same material by the same method. Further, it is possible to easily give the distribution of the thickness of the target depending on the location, and thereby it is possible to control the strength distribution of the magnetic field and the distribution of the temperature on the target surface to control the thickness distribution of the thin film formed.

The method of the present invention can be applied to a conventional planar type target, the bonding between the target and the target holder is unnecessary, and a homogeneous and highly adherent target can be easily manufactured and regenerated. is there.

Using the ceramic rotating cathode target of the present invention, a usual 1 × 1 in a mixed atmosphere of Ar and O _2.
When sputtered in a vacuum of about 0 ⁻³ to 1 × 10 ⁻² Torr, Zr, Ti, Ta, Hf, Mo, W, Nb, Sn,
A low refractive index film made of an oxide containing at least one of La, In, and Cr (hereinafter referred to as metal M) and Si can be uniformly formed at high speed.

Since the target of the present invention has conductivity and the surface oxidation of the target is small during sputtering, direct current (DC) sputtering can be used for film formation, and a uniform film over a large area can be formed at high speed. .. This is Zr, Ti, Ta, Hf, Mo, W, Nb, La, I in the target.
Most of n, Cr, etc. exist as a silicon compound, and Sn exists as a Si—Sn alloy. Since they have less activity to oxygen than Si, they are less likely to be oxidized, so that the decrease in conductivity due to the surface oxidation of the target is suppressed. It is thought to work.

The ceramic rotating cathode target of the present invention can be used in both DC and RF sputtering devices by magnetron sputtering, high-speed film formation and high target use efficiency, and stable film formation is possible. ..

[0046]

【Example】

[Example 1] In this example, a method of manufacturing a Si-Zr ceramic rotating cathode target capable of stably forming an oxide film having a low refractive index and excellent durability at a high speed will be described.

First, ZrO is used as a ceramic powder raw material.
A mixture of ₂ , SiO ₂ and carbon was reacted in a high temperature non-oxidizing atmosphere to obtain a lumpy sintered product. This lumpy powder was placed in a nylon pot mill to produce ZrO ₂ (partially stabilized Zr
It was ground in an ethanol solvent using an O ₂ ) ball for 24 hours. A vinyl acetate / acrylic copolymer binder was added to and mixed with this slurry, and the purity was adjusted to 9 by an explosion-proof spray dryer.
Si-Zr (Si: Zr with 9.5% and average particle diameter of 80 μm)
= 9: 1 (atomic ratio)) Granulated powder was obtained.

The cylindrical target holder is made of copper having an outer diameter of 67.5 mm and a length of 406 mm and is attached to a lathe. The outer surface of the target holder is processed into a screw shape, and Al ₂ O is formed on the outer surface.
_{3 The} surface was roughened by sandblasting with abrasive grains to make it rough. Next, as an undercoat, the first layer Ni-Al
Alloy powder (blending ratio 8: 2) and T as the second layer
Plasma spraying of i metal powder (using Metco sprayer)
Then, coatings each having a film thickness of 50 μm were formed.

The cylindrical target holder subjected to this surface treatment was placed in a HIP-processed stainless steel capsule having an Al ₂ O ₃ fiber paper (1 mm thickness) affixed to its inner surface in advance, and the bottom portion was welded and joined to the HIP. Treated capsules were prepared. The gap between the capsule and the cylindrical target holder was vibration-filled with the above Si-Zr granulated powder using a vibrator. Then, the inside of the stainless steel capsule is depressurized to 10 ^-3 Torr or less and sealed, and HI
It was inserted into a P processing device and subjected to HIP processing.

As the HIP treatment conditions, Ar gas (purity 99.9%) having a temperature of 1000 ° C. and a pressure of 200 MPa was used as a pressure medium, and the treatment was carried out for 1 hour. After HIP processing, the stainless steel capsule was removed, and the outer surface of the Si-Zr ceramic cylindrical target was processed to be smooth, and the inner surface of the target holder was turned by a lathe to give an inner diameter of 50.5 mm.
Processed into a Si-Zr (Si: Zr
= 9: 1 (atomic ratio)) A rotary cathode target having a ceramic film thickness of 5 mm was obtained. The relative density of the obtained Si-Zr ceramics layer was 99.5%, and the oxygen content in the ceramics layer was 0.18% by weight.

The Si-Zr rotary cathode target thus obtained was loaded into a magnetron sputtering apparatus, and a SiZr _x O _y film (Si: Zr: O =) was placed on a glass substrate.
9: 1: 20 (atomic ratio)) was formed. Forming condition is Ar
1 × 10 ⁻³ to 1 × 10 ⁻² Tor in a mixed atmosphere of + O ₂
Sputtering was performed in a vacuum of about r to obtain a 1000 Å low-refractive-index transparent oxide film. The chemical composition Si: Zr atomic ratio of this low refractive index transparent oxide film was the same as the chemical composition of the target.

The above target was more resistant to damage due to heat shock than a planar type target in which ceramics were made by a conventional ceramic method and attached to a target holder. In the above conventional method, cracks occur at a sputtering power of about 1.2 kW and partial peeling occurs, but in the rotating cathode of the present invention, no crack is observed even at 4 kW, arcing does not occur, and stable film formation is possible. With the conventional method, a high film forming rate of 100 Å / sec, which is about four times as high as that of 25 Å / sec, was obtained. The obtained oxide film had a low refractive index of 1.49 and had excellent alkali resistance.

[Examples 2 to 8] Various targets were prepared in the same manner as in Example 1 except that the constituent materials of the target and the proportions thereof were changed, and sputtering was performed using the same targets as in Example 1. A film was formed. However, in Example 2 and Example 6, Ti metal powder was used instead of Mo metal powder, and Ni—Al (50 μm) / Ti (50 μm) was used.
m) was used as a two-layer undercoat. In addition, in Example 5, a single layer of Ni—Al (100 μm) was used as the undercoat. For Examples 3, 4, 7, and 8, Example 1 was used.
I used the same undercoat. In all of the above, the method of forming the undercoat was the same as in Example 1.

Comparative Example 1 Si was prepared in the same manner as in Example 1.
The powder was pulverized and granulated, and a rotating cathode was prepared in the same procedure as in Example 1 using this powder. The film was formed under the same sputtering conditions, but arcing was severely generated, and the film could not be stably formed.

COMPARATIVE EXAMPLE 2 Si-Zr (Si: Zr = 9: 1 (atomic ratio)) agglomerated powder synthesized in the same manner as in Example 1 was pulverized and classified to obtain 75 having a purity of 99.5%. ~ 20μ
A rotating cathode target was obtained in the same manner as in Example 1 except that a thermal spraying powder having an m particle diameter was used and a ceramic layer as a target was formed on the undercoat by plasma spraying in the atmosphere. The relative density of this ceramic target layer was 89%, and the oxygen content was 3.1% by weight.

A film was formed by sputtering using the target in the same manner as in Example 1. During the sputtering, the arcing at the initial stage of use was vigorous, pre-sputtering was required for about 40 minutes, and although a small arcing occurred in the high-speed film formation of 4 kW, the film formation rate four times that of the conventional film was obtained. Although no cracking or peeling of the target ceramics layer was observed during sputtering, fine arcing spots were formed in places on the target surface.

Comparative Example 3 Si-Zr similar to Example 1
A powder of (Si: Zr = 9: 1 (atomic ratio)) was hot pressed to form a sintered body, which was bonded to a planar type backing plate using In to form a planar type target. When sputtering was performed using this, the target was cracked or partly peeled off, and stable film formation could not be performed.

Table 1 shows a comparison between Examples 1 to 8 and Comparative Examples 1 to 3.
Shown in. The alkali resistance of the films shown in Table 1 is 0.1N
As a result of immersing in NaOH at room temperature for 240 hours, ◯ indicates that the rate of change in film thickness before immersion is 10%, and x indicates that the film has dissolved.

[0059]

[Table 1]

[0060]

According to the method of the present invention, the target is HI
Since it is manufactured by simultaneously performing sintering and bonding using the P treatment method, it does not require conventional ceramics manufacturing equipment, and can be easily manufactured at low cost and in a short time without a processing and bonding process. Can be applied to.
In particular, powders of refractory substances and refractory metals which are difficult to be made into ceramics are cheaper, and it is particularly effective when such substances are targeted.

When the rotating cathode target of the present invention is used, the cooling efficiency during sputtering is high, and even if the sputtering power is increased, there is no cracking or damage to the target, and stable high-speed film formation at low temperatures is possible. The industrial value is enormous because the productivity of large-area glass for automobiles and automobiles is remarkably improved and the target use efficiency is increased.

By using the rotating cathode of the present invention, a transparent thin film having a low refractive index and excellent alkali resistance can be stably provided at a high speed over a large area. Further, the optical design of the thin film can be facilitated by combining with the transparent oxide thin film having a high refractive index.

Since the low refractive index film obtained by the present invention has chemical stability, it can be used as an overcoat for various articles. For example, it is most suitable for the outermost layer of heat-reflecting glass for buildings and automobiles, protective plate of the reading part of bar code readers, antireflection film, spectacle lenses, etc.
In addition, it can be widely used as a mechanical element and can be used as a coating material for sliding members.

[Brief description of drawings]

FIG. 1 is a sectional view of an example of a HIP processing capsule used in the present invention.

[Explanation of symbols]

1: Stainless steel capsule 2: Surface-treated copper cylindrical target holder 3: Al ₂ O ₃ ceramics fiber paper 4: Filled ceramics powder

Claims (3)

[Claims] 1. A metal or alloy having a roughened outer surface of a cylindrical target holder and having a coefficient of thermal expansion intermediate between the coefficient of thermal expansion of a ceramic layer to be formed later and the coefficient of thermal expansion of the target holder. And at least one layer of a metal or an alloy having a coefficient of thermal expansion close to that of the ceramics layer is formed as an undercoat by plasma spraying, and then the outer surface of the cylindrical target holder is surrounded. Place the ceramic powder or a compact of such powder in
A method of manufacturing a ceramic rotating cathode target, which comprises hot isostatic pressing, wherein the ceramic powder is Z
r, Ti, Ta, Hf, Mo, W, Nb, Sn, La,
At least one of In and Cr (hereinafter referred to as metal M)
And a powder containing Si as a main component and the total amount of metal M and Si in an atomic ratio of 4:96 to 35:65. 2. On the outer surface of the cylindrical target holder,
A ceramic layer serving as a target to be sputtered is formed, a layer made of a metal or an alloy having a thermal expansion coefficient intermediate between the thermal expansion coefficient of the ceramic layer and the thermal expansion coefficient of the target holder, and the thermal expansion of the ceramic layer. A ceramic rotating cathode target in which at least one layer of a metal or an alloy having a coefficient of thermal expansion close to a coefficient is formed as an undercoat between the ceramic layer and the target holder, and the ceramic layer Is Zr, Ti, T
At least one of a, Hf, Mo, W, Nb, Sn, La, In, and Cr (hereinafter referred to as metal M) and Si are main components, and the total amount of metal M and Si are in an atomic ratio of 4: 96
A ceramic rotating cathode target having a ratio of ˜35: 65. 3. A film forming method by sputtering, wherein a low refractive index film is formed by sputtering the ceramic rotating cathode target according to claim 2.