JP2002069614A - Production method for titanium nitride film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method for a titanium nitride film, capable of forming the titanium nitride film good in quality and having functions such as a reflection property suitable for a surface-treatment film of, for example a cathode-ray tube, a photoabsorption property for contact improvement, the prevention of leak of electromagnetic field, and the like. SOLUTION: The titanium nitride film can be formed by keeping a partial pressure of residual water in atmosphere for film-forming at 0.3% or below to a total pressure, when this titanium film is formed by a reactive sputtering method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a titanium nitride film, and more particularly to a method suitable for forming a titanium nitride film constituting a surface treatment film of a display device having a cathode ray tube or the like.

[0002]

2. Description of the Related Art In recent years, in a display device, for example, a display device provided with a color cathode ray tube, surface treatment performed on the front surface of the face panel of the color cathode ray tube includes light absorption for preventing reflection, improving contrast, and improving the contrast. In order to satisfy the function of preventing a leakage electromagnetic field, a titanium nitride film is used. As a method for forming a titanium nitride film, a reactive sputtering method is widely used because it is excellent in mass productivity and a relatively uniform film distribution can be easily obtained over a large area.

In the reactive sputtering method, high-speed ions generated by glow discharge in a controlled reduced-pressure atmosphere collide with a target, which is a starting material, and attach target material particles that fly out to the opposite substrate surface.
This is a technique of depositing and forming a film. Also, in a reduced pressure atmosphere,
By selecting a reactive gas such as oxygen or nitrogen, the metal target particles can be oxidized or nitrided to form a film of an oxide or a nitride.

In forming a titanium nitride film, a desired film is formed on a target of titanium metal under a reduced pressure atmosphere of a mixture of argon and nitrogen.

[0005]

By the way, in a large-sized sputtering apparatus in consideration of mass productivity, the film forming chamber is large, and the area is effectively large due to the deposition material and the film material deposited on the vessel wall. Gas molecules adsorbed on the surface,
In particular, since a large amount of H ₂ O is released, the H ₂ O concentration in the reduced-pressure atmosphere increases, and there is a problem that titanium nitride is oxidized by the oxidizing action of the H ₂ O gas.

[0006] In the titanium nitride film, the H ₂ O gas causes an inconvenience that the electrical conductivity of the film is deteriorated, and the light absorption of the film is impaired. In addition, the amount of H ₂ O released from the substrate carried by the short tact time is not negligible.

The outgassing of adsorbed H ₂ O is a physical phenomenon that is difficult to control actively. In order to solve this problem, it is necessary to exhaust gas for a long time before the released gas is exhausted by the vacuum pump. However, long-term exhaustion causes a long preparation time until the start of production, which leads to a large production hindrance.

At present, the relationship between the electrical conductivity and the light absorption of the titanium nitride film, which are acceptable characteristics of the product, and the partial pressure level of H ₂ O in the film formation atmosphere has not been clarified. In addition, sometimes, a sudden change in the amount of water adsorbed on the substrate causes a product defect.

The present invention has been made in view of the above points, and provides a method of manufacturing a high-quality titanium nitride film.

[0010]

According to a method of manufacturing a titanium nitride film according to the present invention, when forming a titanium nitride film by a reactive sputtering method, a partial pressure of residual moisture in a film formation atmosphere is reduced to a total pressure. On the other hand, the titanium nitride film is formed at 0.3% or less.

In the manufacturing method of the present invention, a titanium nitride film is formed by setting the partial pressure of the residual moisture in the film forming atmosphere to 0.3% or less of the total pressure, so that a desired sheet resistance value is obtained. Then, a titanium nitride film having a required light absorption rate is formed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, referring to FIG. 1, a surface treatment film having a titanium nitride film applied to the present invention, for example, a light treatment surface treatment film of a color cathode ray tube having a flat face panel surface shape. One embodiment of the absorptive anti-reflection film will be described. The light absorbing anti-reflection film 1 is formed on a light absorbing thick film 3 formed on a glass base material (for example, a face panel of a cathode ray tube) 2 and on the light absorbing thick film 3, And an antireflection multilayer film 4 for attenuating reflected light with respect to incident light by light interference.

The light-absorbing thick film 3 contains 10 pigment fine particles.
A film having a physical film thickness of not less than nm and not more than 1000 nm, preferably not less than 100 nm and not more than 800 nm, comprising silicon oxide (SiO ₂ ) as a main component, and fine particles of the silicon oxide serving as a binder to form a film. . In order to obtain a desired refractive index distribution inside the light absorbing thick film 3,
It contains pigment fine particles and high refractive index fine particles. As the pigment fine particles, carbon fine particles (carbon black), inorganic pigment fine particles of a compound such as iron, cobalt, manganese, tin, and ruthenium, and organic pigment fine particles of an organic substance can be used. By containing pigment fine particles, the transmittance of the light-absorbing thick film 3 can be adjusted. As the high refractive index fine particles, fine particles of a high refractive index material such as tin oxide (refractive index: about 2.0) and titanium oxide (refractive index: about 2.6) can be used. By containing fine particles having a high refractive index, the refractive index of the light absorbing thick film 3 can be adjusted.

The light absorbing thick film 3 can be formed by, for example, a wet coating method. In the wet coating method, the spin coating method is most suitable for obtaining a uniform film thickness. In addition, a roll coating method, a bar coating method, a dip coating method, a spray method, and the like can also be used.

The antireflection multilayer film 4 is composed of a titanium nitride film 5 having at least one layer having a sheet resistance of not less than 10 Ω / □ and not more than 1000 Ω / □, preferably not more than 500 Ω / □. In this example, the titanium nitride film 5 and the silicon oxide (SiO ₂ ) film 6 constitute the antireflection multilayer film 4. The titanium nitride film 5 is a stoichiometric TiN film, is optically a light absorber having a refractive index of 1.6 and an extinction coefficient of 0.9, and has electrical conductivity. The titanium nitride film 5 and the silicon oxide film 6 constituting the antireflection multilayer film 4 are formed by a DC reactive sputtering method.

In a cathode ray tube having a flat outer surface shape of the face panel, a difference in transmittance occurs due to a difference in panel thickness between the center portion and the corner portion, and as a result, uniformity of luminance is deteriorated. By increasing the transmittance and forming the light-absorbing anti-reflection film 1 on the outer surface of the face panel, it is possible to control the overall transmittance, obtain a good contrast, and have a function of preventing a leakage electromagnetic field. .

FIG. 2 shows an example of a Gallar cathode ray tube having the above-mentioned light-absorbing antireflection film on the outer surface of the face panel.
The color cathode ray tube 30 is formed of a glass cathode ray tube 21 having a panel portion 21a, a funnel portion 21b, and a neck portion 21c. The panel portion 21a has an outer surface formed of panel glass having a flat shape, and has a peripheral portion (particularly, a corner portion) thicker than a central portion in order to oppose an external pressure. An electron gun 23 for emitting an electron beam is enclosed and arranged in the neck portion 21c. Neck 21c
A deflection yoke 2 for deflecting the electron beam emitted from the electron gun 23 is provided on the outside of the tube extending from the tube to the funnel portion 21b.
4 are arranged. Then, the above-described light-absorbing anti-reflection film 1 for preventing reflection, improving contrast, and preventing a leakage electromagnetic field is formed on the outer surface of the panel portion 21a.

A display device is provided with the color cathode ray tube 30 described above.

Next, an embodiment of a method for manufacturing a titanium nitride film according to the present invention will be described. In the present embodiment,
When forming a titanium nitride film, in this example, the titanium nitride film 5 constituting the light-absorbing anti-reflection film 1 by a reactive sputtering method, the partial pressure of residual moisture in the film formation atmosphere is set to the total pressure. 0.3% or less, preferably 0.1% or less. As the reaction gas, a mixed gas of nitrogen gas and argon gas is used. When the partial pressure of the residual moisture is 0.3% or less, a titanium nitride film 5 having a sheet resistance value of 500Ω / □ or less and a light transmittance of 70% or less, which can obtain a shielding effect of a leakage electromagnetic field of a cathode ray tube, is obtained. Can be If the partial pressure of the residual moisture is 0.1%, the sheet resistance value is 500Ω / □ or less and the light transmittance is 7%.
The titanium nitride film 5 can be formed in a stable state at 0% or less. When the partial pressure of the residual moisture exceeds 0.3%, the sheet resistance value exceeds 500Ω / □.

The DC reactive sputtering method is advantageous in that the control of the film thickness is relatively easy and a relatively uniform film thickness distribution can be obtained for a large-area substrate. Further, the in-line type sputtering apparatus is excellent in that lamination of a multilayer film is facilitated. FIG. 3 shows an inline passivation film which is suitable for continuously forming the titanium nitride film 5 and the silicon oxide film 6 constituting the light absorbing antireflection film 1 of the above-mentioned cathode ray tube and which is manufactured in consideration of mass productivity. 1 shows a film type DC reactive sputtering apparatus.

This reactive sputtering apparatus 11
An entry lock chamber 12 for carrying a plurality of cathode ray tubes 10 serving as works, a work passing chamber 13, a first film forming chamber 14 for forming a titanium nitride film 5, a work passing chamber 15, 1
6, a plurality of chambers for depositing the silicon oxide film 6, in this example, five consecutive second deposition chambers 17 [17A, 17B, 17]
C, 17D, 17E], a work passage chamber 18 and an exit lock chamber 19 for carrying out the work are successively arranged. Gate valves 21 are arranged on the work loading side and the loading side of each of the chambers 12 to 19 so as to be openable and closable in a vertical direction.

A metal Ti target 22 is disposed in the first film forming chamber 14, and a mixed gas of nitrogen gas and argon gas from a nitrogen gas cylinder 23 and an argon cylinder 24 is supplied through a supply pipe 27. First film forming chamber 14
Is configured to be evacuated to a required degree of vacuum by the diffusion pump 28. In the second film forming chambers 17 [17A to 17E], a pair of Si targets 29 is disposed, and oxygen gas is supplied from the oxygen gas cylinder 25 through the supply pipe 30. Each of the second film forming chambers 17A to 17E is evacuated to a required degree of vacuum by the diffusion pump 28.

Each work passage chamber 13, 15, 16, 18
Is configured as a so-called vacuum chamber. A mixed gas of nitrogen and argon is supplied through the supply pipe 27 into the entry lock chamber 12 and the work passage chambers 13 and 15. Oxygen gas is supplied through the supply pipe 30 into the work passage chambers 15 and 18 and the exit lock chamber 19. Work passage room 1
5 is configured such that the mixed gas and the oxygen gas are switched and supplied.

In the reactive sputtering device 11,
A plurality of cathode ray tubes 10 serving as works are carried into the entry lock chamber 12 with the gate valve 21 opened. After the gate valve 21 is closed, a vacuum pump (not shown)
Thereby, the inside of the entry lock chamber 21 is evacuated to a required degree of vacuum. Next, a mixed gas of nitrogen and argon is supplied into the entry lock chamber 12, the work passage chamber 13, the first film formation chamber 14, and the work passage chamber 15 at a required flow rate. The cathode ray tube 10 is connected to the first film forming chamber 14 through the work passage chamber 13.
Transported to In the first film forming chamber, the mixed gas is supplied after being evacuated to a required degree of vacuum by the diffusion pump 28. In the first film forming chamber 14, the titanium nitride film 5 is formed on the light absorbing thick film 3 formed by the spin coating method on the cathode ray tube 10, which is a work, by the reactive sputtering process.

Next, the cathode ray tube 10 is moved to the work passage chamber 15.
Transported to In the work passage chamber 15, the room is replaced with oxygen gas from the mixed gas. Also, the work is loaded,
Each passing chamber 16 and the second film forming chamber 17 [17A
17E], the work passage chamber 18 and the exit lock chamber 19 are also evacuated by a vacuum pump (not shown) and a diffusion pump 28, and then oxygen gas is supplied at a required flow rate. The atmosphere in each of the rooms 10 to 19 is the same.

The cathode ray tube 10 is conveyed to the first chamber 17A of the second film forming chamber 17 through the work passage chamber 16, where it is subjected to a reactive sputtering process, and the silicon oxide film 6 is formed on the titanium nitride film 5 of the cathode ray tube. A film is formed. After this, the second
Second, third, fourth, and fifth chambers 17B to 17B of film forming chamber 17
7E, a silicon oxide film 6 is formed to a required thickness. After the film formation, the cathode ray tube 10 is transported to the exit lock chamber 19 via the work passage chamber 18, and after being brought to normal pressure, the gate valve 21 is opened and carried out.

Next, in the first film forming chamber 14 of the DC reactive sputtering apparatus 11, the titanium nitride film 5
An example of forming a film will be described. Cathode ray tube 10 as a work
Is transported to the first film forming chamber 14, by applying a required negative voltage to the metal Ti target 22, for example, a negative voltage of about 300 V to 500 V, the atmospheric gas is ionized and a glow discharge occurs. As a discharge gas, the above-mentioned mixed gas of nitrogen and argon (nitrogen 15% by volume) is introduced at a required flow rate, for example, at a flow rate of about 300 sccm, and is introduced into the first film forming chamber 14. The flow rate is controlled so that the pressure becomes a required pressure, for example, 3 × 10 ⁻³ Torr. Sputtering is performed under these conditions, and the titanium nitride film 5 having a physical thickness of 5 to 30 nm is formed by passing through the cathode ray tube 10 at a speed of 1 m / min.

In order to exhaust moisture during the sputtering process, the use of a cryopanel device that cools the SUS plate to a temperature of about 80 K and traps moisture as ice solids can effectively reduce the moisture partial pressure. DC shown in FIG.
When a cryopanel device having an appropriate capacity is provided in the reactive sputtering device 11, as shown in FIG. 4, the sputtering start pressure after introducing the mixed gas is 2.0 × 10 ^−5.
The evacuation time to reach Torr is 300 min, which is 900 min without a cryopanel device.
Is greatly reduced to 1/3 as compared with. In FIG. 4, a curve a indicates the case where the cryopanel device is provided, and a curve b indicates the case where the cryopanel device is not provided.

Here, the gas partial pressure during the process of forming the titanium nitride film was measured by a quadrupole mass spectrometer, and the residual water partial pressure, the electrical conductivity of the formed titanium nitride film, and the light transmittance were measured. Is shown in FIG. In FIG. 5, the curve c is the sheet resistance, and the curve d is the light transmittance. In order to obtain high quality titanium nitride film characteristics, an appropriate sheet resistance value as a shielding effect of a leakage electromagnetic field of a cathode ray tube is 500Ω / □.
It is necessary to set a condition such that the transmittance is 70% or less at which a stable numerical value is obtained in the process. From FIG. 5, it is necessary that the partial pressure level of residual moisture during sputtering satisfying this condition is 1.0 × 10 ⁻⁵ Torr or less, and preferably, the partial pressure level is 4.0 × 10 ⁵ at which the sheet resistance value is saturated.
It turns out that ^-6 or less is desirable. Therefore, the above 3.0 × 1
Assuming that the total pressure is 0 ^-3 Torr, the partial pressure of the residual moisture in the film formation atmosphere is 0.3% or less, preferably 0.1% or less with respect to the total pressure. By forming the titanium nitride film under the conditions, the electrical conductivity and the light absorption of the titanium nitride film are not impaired.

According to the present embodiment, when a titanium metal film is reactively sputtered in a mixed gas atmosphere of nitrogen and argon to form a titanium nitride film, the partial pressure of the residual moisture in the film formation atmosphere is reduced. By controlling the total pressure to 0.3% or less, preferably 0.1% or less, it is possible to manufacture a high-quality titanium nitride film that does not impair the electrical conductivity and the light absorption. Therefore, the present invention is suitably applied to the formation of a light-absorbing antireflection film as a so-called surface treatment film formed on the front surface of the face panel of a cathode ray tube, particularly, a titanium nitride film. That is, the residual moisture partial pressure for obtaining a high-quality titanium nitride film is quantified, and by managing this value, the product at the time of production, that is, the titanium nitride film itself, or an absorptive anti-reflection film, Furthermore, it is possible to prevent a cathode ray tube having a light absorbing antireflection film on the outer surface of the face panel from being defective.

In the above example, the present invention was applied to the production of a titanium nitride film constituting the surface treatment film of a cathode ray tube, but the present invention is also applicable to the production of a titanium nitride film of other products.

[0032]

According to the present invention, it is possible to manufacture a high-quality titanium nitride film having electrical conductivity and light absorbing properties that are acceptable as products. In particular, the light transmittance is 70
% Or less, a titanium nitride film having a sheet resistance of 500 Ω / □ or less can be formed. For example, in the case of a light-absorbing anti-reflection film as a surface treatment film of a flat panel type cathode ray tube, a titanium nitride film satisfying functions such as anti-reflection, light absorption for improving contrast, and prevention of leakage electromagnetic field. Suitable.

According to the present invention, the residual moisture partial pressure in the sputtering atmosphere for obtaining a high quality titanium nitride film is quantified. Failure can be prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a light-absorbing reflective film having a titanium nitride film to be a surface treatment film of a cathode ray tube.

FIG. 2 is a configuration diagram illustrating an example of a cathode ray tube having a light absorbing reflective film formed on an outer surface of a face panel.

FIG. 3 is a configuration diagram showing an example of a reactive sputtering apparatus used for forming a titanium nitride film of the present invention.

FIG. 4 is a graph showing the relationship between the pressure in the reactive sputtering apparatus and the evacuation time depending on the presence or absence of a clario panel apparatus for trapping moisture.

FIG. 5 is a graph showing the relationship between the partial pressure of water at the time of forming a titanium nitride film, the film, the sheet resistance, and the light transmittance.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Light absorption antireflection film, 2 ... Base material, 3 ...
Light absorbing thick film, 5: titanium nitride film, 6: silicon oxide film, 11: in-line passing film forming type reactive sputtering device, 30: color cathode ray tube

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01J 9/20 G02B 1/10 A

Claims (3)

[Claims] When a titanium nitride film is formed by a reactive sputtering method, a partial pressure of residual moisture in a film forming atmosphere is 0.3% with respect to a total pressure.
A method for manufacturing a titanium nitride film, comprising forming the titanium nitride film as follows. 2. The method for producing a titanium nitride film according to claim 1, wherein said titanium nitride film is formed by sputtering metal titanium in a mixed atmosphere of argon and nitrogen. 3. The method for producing a titanium nitride film according to claim 1, wherein said titanium nitride film having a sheet resistance of 500 Ω / □ or less is formed.