JPH03140460A - Sputtering method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a sputtering method in a sputtering manufacturing apparatus.

[Prior Art 1] In recent years, there has been a great demand for transparent plastic substrates, especially thin plate materials, but on the other hand, transparent plastic substrates and thin plate materials are easily scratched due to their low surface hardness and scratch strength, making them difficult to put into practical use. inferior to sex. Therefore, as a surface modification method for transparent plastic substrates and thin plate materials, for example, transparent plastic substrates and thin plate materials are often coated with a dielectric protective material. However, the long-term M tendency of the dielectric protective layer is not ensured, and cracks occur in the dielectric protective layer due to the difference in thermal characteristics between the transparent plastic substrate and the dielectric protective layer, especially under high temperature and high humidity conditions. do. Therefore, it has not been put into practical use where higher heat resistance and thermal shock resistance are required.

Therefore, we conducted a comparative study 3 regarding conventional upstream sputtering methods.
I have been exposed.

Therefore, a conventional method for manufacturing a dielectric protective layer using a sputtering manufacturing apparatus will be described with reference to a second perspective view of FIG.

FIG. 2 is a schematic cross-sectional view of a sputtering chamber in which a dielectric protective layer is formed.

10 is the vacuum chamber, 11 is the vacuum pump, 12 is Yuichi get,
13 is a tray that rotates on an axis; 14 is a holding plate made of a transparent plastic substrate and a thin plate material; and 15 is a transparent plastic substrate and a thin plate material.

16 is an argon and nitrogen supply port which is a sputtering gas, and the sputtering gas is supplied from the same system with a constant flow rate ratio.

! @1 stage is transparent plastic substrate and thin plate material. 15 is held by 14 and set on a rotating tray 13, and the sputtering chamber 10 is brought to a high vacuum using the vacuum pump 11. In the W&2 stage, while rotating 13 on the axis,
That is, transparent plastic substrate and thin plate material 15
While rotating, a constant flow rate of argon and nitrogen is supplied from 16 sputtering gas supply ports. Third
The step is to form a dielectric protective layer from 12 terded to 15 using RF fixed magnetron reactive sputtering method.
The transparent plastic substrate and thin plate material are uniformly laminated without defects. In addition, the dielectric protective layer produced by the conventional manufacturing method is generally 7 mol 7 as, that is, amorphous, and has greatly improved the surface hardness and scratch strength of transparent plastic substrates and thin plate materials.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional technology, the fracture toughness of the dielectric protective layer is low in a high temperature atmosphere of 80° C. or higher and a high humidity atmosphere of 85% RH or higher, so the dielectric protection cannot be achieved. The problem was that cracks occurred in the layers.

SUMMARY OF THE INVENTION The present invention aims to solve these problems, and its purpose is to provide a sputtering method for producing a thin film with significantly improved thermal shock resistance and excellent long-term reliability. be.

[Means for Solving the Problems] The sputtering method of the present invention is a sputtering method for producing single-layer and multi-layer thin films, and is characterized by having a step of continuously grading the composition in the thickness direction of the thin film.

[Function] To describe the function of the present invention, by forming the dielectric protective layer while continuously grading the composition in the film thickness direction, micro interfaces do not occur inside the dielectric protective layer, and the fracture toughness is improved. has improved significantly.

Therefore, even in a high-temperature atmosphere of 80° C. or higher and a high-temperature atmosphere of 85% RH or higher, no cracks occur in the dielectric protective layer.

[Example] An example of a specific field of application of the present invention is a manufacturing process of a dielectric protective layer, which will be described in detail below based on Examples.

FIG. 1 is a sectional wedge view of a sputtering chamber in which a dielectric protective layer is formed in an embodiment of the present invention.

1 is a sputtering chamber, which is preferably maintained at a high degree of vacuum of 10' Torr or more. Reference numeral 2 denotes a vacuum pump, which has a high evacuation capacity in order to evacuate and maintain the batter chamber 1 at a high degree of vacuum. An oil-free pump is preferable, and it is desirable to use a cryopump or a turbomolecular pump. 3 is A IaS i+o
It is a tarded material with a composition o-a (a is a constant). 4 is a tray that rotates on an axis; 5 is a holding plate made of a transparent plastic substrate and a thin plate material; 6 is a transparent plastic substrate and a thin plate material presser; and 7 is a transparent plastic substrate and a thin plate material. Reference numeral 8 denotes a supply system for nitrogen, which is a sputtering gas, and the flow rate can be increased or decreased intermittently using an automatic electric control valve. Similarly, in the case of 9, the flow rate can be intermittently increased or decreased using an automatic electrically operated valve in the supply system for argon, which is a sputtering gas.

In the first step, a transparent plastic substrate and a base material 7 made of a thin plate material are held by a holding plate 5 and a material presser 6, set on a rotating tray 4, and a vacuum pump 2 is used to raise the sputtering chamber 1 to a high temperature. Make a vacuum.

In the second step, while rotating the tray 4, that is, rotating the base materials, which are the transparent plastic substrate and the thin plate material, the sputtering of 8 and 9 is carried out from the large supply system.
Supply argon and nitrogen at default flow rates.

The third step is between the tarded and the substrate l! While the RF power and the argon flow rate used as sputtering gas were fixed, the nitrogen flow rate was changed using an automatic electrically operated valve.
While increasing or decreasing the amount intermittently as shown in the figure, functionally graded Al5iN, which is a dielectric protective layer, was
llll onto a transparent plastic substrate 7 and a thin plate material 70
0 to 2000 (A) Laminated film formation.

FIG. 3 is a diagram showing the time dependence of the flow rate of nitrogen, which is a sputtering gas. The vertical axis is the nitrogen inflow rate (SCCM)
), and the horizontal axis represents time (minutes).

FIG. 4 is an enlarged schematic cross-sectional view of a functionally graded AIs iN film which is a dielectric protective layer produced by the sputtering method of the present invention. On the transparent plastic substrate and thin plate material 17, the functionally graded Al5iN film 18 is composed of silicon atoms 19 (Si), nitrogen atoms 20 (N) and aluminum atoms 21 (AI), (A Is i)-N
+o. It is represented by the compositional formula -.

FIG. 5 is a diagram showing the composition distribution in the film thickness direction of functionally graded Al5iNli. The vertical axis represents the composition of AlSi, and the horizontal axis represents the position in the film thickness direction from the transparent plastic substrate and the thin plate material side to the film surface.
The composition X of (A Is i) is 20 to 20 in the film thickness direction.
It can be seen that the slope is intermittently inclined so that no interface occurs between 80 (at%).

Here, X is set to 20 (at%) or more because it is possible to use a wider range of applications if the entire transmittance of the functionally graded Al5iN film 18 is 90 (%) or more to make it transparent.

Therefore, the characteristics inside the functionally graded film are those on the side of the transparent plastic substrate and the thin plate material 17, which are closer to the (A Is i) part, and in particular exhibit thermal characteristics closer to those of the transparent plastic substrate 17 and the thin plate material 17. The side is more A Is
It has properties close to those of iN, particularly heat resistance, surface hardness, and water vapor impermeability, and the functionally graded Al5iN film 18 as a whole has high fracture toughness.

Heat resistance: 1 surface hardness and - water vapor impermeability.

Next, as a comparative example, dielectric protective layers produced by the conventional method and the sputtering method of the present invention, Al5iN
Table 1 shows the results of a comparison of crack resistance under high-temperature heating with 50 samples for each.

From Table 1, in the sputtering method, if the dielectric protection material and A Is iN film are not prepared by tilting the thickness direction composition of the thin film so as not to generate an interface, the temperature at 70°C9
At 0%RH, no cracks (HIV) were observed even after 500 hours, but at 80°C and 85%R.
At temperatures above H, severe cracks occur,
It can be seen that the number increases with time. On the other hand, according to the present invention, it is possible to fabricate a dielectric protective layer, an Al5iN film, which does not generate any cracks even at 80° C. and 90% RH, and has significantly improved thermal shock resistance and long-term reliability. was completed.

In this example, the dielectric protective layer is made of Al5iN.
However, it is effective if the ceramic dielectric is composed of at least one element and one or two substances reactive with the element. In particular, the elements are A1,
S is T js Mgs Zn5Ca1 Sr1
It is preferable that at least one kind is selected from Ba% Zr, PbS Nb, and Ta, and the reactive substance is N,
It is preferable to be composed of at least one element selected from OlS.

Further, even when the present invention is applied to a method for manufacturing a protective layer of a magneto-optical recording medium, the same effects can be sufficiently obtained.

In addition, in this example, a functionally graded Al5iN film was fabricated by intermittently changing the flow rate of the nitrogen bus, which is the sputtering gas, using an automatic electrically operated valve. Incline function A is achieved by intermittently changing the flow rate of the argon sputtering bus using a type control valve.
There is no problem in producing a 15iN film. Furthermore, oxygen (O) can also be used as a sputtering gas.

In addition, the tered power source is not limited to RF,
There is no problem in using a DC power supply,
The magnet used to apply the magnetic field is not limited to a fixed type, and may be a rotating type or a movable type.

Furthermore, the thin film is not limited to a dielectric protective layer, and any thin film produced using a sputtering method can be used without any problem. By doing so, it becomes possible to add new functions.

[Effects of the Invention] As described above, according to the present invention, in the sputtering method for forming single-layer and multi-layer films, the dielectric protective layer is manufactured while the composition in the film thickness direction is continuously graded. , compared to the conventional wide dielectric protective layer, there are no micro interfaces inside the dielectric protective layer1, and the fracture toughness of the dielectric protective layer is greatly improved under high temperature and high humidity conditions, and no cracks occur. Therefore, it has great effects in greatly improving the thermal shock resistance and long-term reliability of the dielectric protective layer.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a sputtering chamber in which a dielectric protective layer is formed in an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view of a conventional sputtering chamber in which a dielectric protective layer is formed. FIG. 3 is a diagram showing the time dependence of the flow rate of nitrogen, which is a sputtering gas. FIG. The figure shows the composition distribution in the film thickness direction of the functionally graded Al5iN film. 1... Sputtering chamber, 2... Vacuum pump, 3... A IaS i+. . -A target having a composition of a (a is a constant); 4...Tray that rotates on an axis; 5...a transparent plastic substrate and a thin plate material holding plate; 6...a transparent plastic substrate and a thin plate material holder; 7
...Transparent plastic substrate and thin plate material, 8...
Supply system for nitrogen, which is sputtering gas (within automatic electric operation valve), 9... Supply system for argon, which is sputtering gas (with built-in automatic electric operation valve), 10... Vacuum chamber, 11... Vacuum pump, 12... Target, 13... Shaft-rotating tray 14... Transparent plastic substrate and holding plate made of thin plate material, 15... Transparent plastic substrate and thin plate material, 16
...Sputtering gas argon and nitrogen supply port, 17...Transparent plastic substrate and thin plate material, 18
...Functionally graded Al5iN film, 19...Silicon atom, Si 20...Nitrogen atom, N, 21...Aluminum atom, AI.

Claims (2)

[Claims] 1. A sputtering method for producing single-layer and multilayer thin films, the sputtering method comprising the step of continuously grading the composition of the thin film in the thickness direction. 2. The sputtering method according to claim 1, wherein the flow rate of the sputtering gas composed of at least one selected from argon (Ar), nitrogen (N), and oxygen (O) is continuously changed, A sputtering method in which the composition of the thin film is graded in the thickness direction.