JPH0551729A - Formation of pattern of thin synthetic resin film - Google Patents

Abstract

PURPOSE:To simply form a pattern of a thin synthetic resin film having satisfactory clearness over the entire surface of a substrate without leaving foreign matter on the surface of the substrate and to facilitate the formation of a multilayered film when the insulating film of a semiconductor device, a passivation film or the dielectric film of a plastic capacitor is formed. CONSTITUTION:When a thin synthetic resin film is formed on a substrate 3 in vacuum, a mask 10 made of a thin metal sheet or a flexible film having ferromagnetism is stuck to the entire surface of the substrate 3 by attraction to an electromagnet 11 set behind the substrate 3 so as to form a pattern. A thin synthetic resin film having a clear pattern over the entire surface of the substrate can be formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin thin film used for a semiconductor element or an electrostatic chuck, such as an insulating film, a passivation film, a soft error film, a dielectric of a plastic capacitor, etc. Pattern creation method.

[0002]

2. Description of the Related Art Conventionally, the following method has been known as a method for forming a pattern of a synthetic resin thin film on a substrate in a vacuum. (1) A negative image is formed on the surface of a substrate by using a silk screen printing method or a photoresist method, then a synthetic resin thin film is formed on the entire surface, and the negative image forming material is dissolved in a solution in which the negative image forming material is dissolved. "Lift-off method" in which a synthetic resin thin film formed on the surface of the film is dissolved and the pattern is created by removing it. (2) A synthetic resin thin film is formed on the entire surface of the substrate, a positive pattern is formed on the synthetic resin thin film by using silk screen printing or photoresist, and then the exposed portion is removed by wet etching or dry etching. A "photo-etching method" in which a positive pattern forming material is removed with a solution or the like to create a pattern. (3) Approach the surface of the substrate,
Alternatively, a "mask method" in which a negative pattern mask is placed in contact with each other, then a synthetic resin thin film is formed on the entire surface of the mask, and then the mask is removed to create a pattern
Are known.

[0003]

However, such a synthetic resin thin film pattern forming method has the following problems. That is, in the case of the "lift-off method", foreign matter remains on the surface of the substrate. Further, in the case of the “photo etching method”, the pattern forming process is complicated and the processing of the multilayer film is complicated. Further, in the case of the "mask method", no foreign matter remains on the substrate surface, the pattern forming process is simple and the multilayer film is easy to prepare, but due to the warp of the substrate surface and the unevenness of the formed multilayer film surface, It is difficult to bring the mask into close contact with the entire surface of the substrate, and there is a problem that an unclear pattern is partially formed.

The reason why a clear pattern cannot be obtained by the conventional mask forming method "mask method" is that the synthetic resin raw material monomer evaporates from the evaporation source and adheres to the wall surface of the apparatus. Re-evaporates from there and deposits on the substrate. As a result, the directivity of vapor deposition is greatly expanded, and even if there is a slight gap between the substrate and the mask, the sharpness of the pattern greatly decreases due to the obliquely incident monomer. Further, since the mask is installed close to or in contact with the surface of the substrate, it is difficult to adhere the mask to the entire surface of the substrate due to the warp of the substrate surface and the unevenness of the formed multilayer film surface. Therefore, there is a problem that a gap is partially formed between the substrate surface and the mask, and the sharpness of the pattern is significantly reduced in this gap.

The present invention solves such a problem. When a foreign substance does not remain on the substrate surface, the pattern forming process is simple, a multilayer film is easily formed, and the substrate surface has a warp or irregularity. However, it is an object of the present invention to provide a method for forming a pattern of a synthetic resin thin film, which allows a mask to be brought into close contact with the entire surface of a substrate and a clear pattern to be obtained over the entire surface of the substrate.

[0006]

In order to solve this problem, the present invention provides a method for producing a synthetic resin thin film on a substrate in a vacuum, using a flexible film having ferromagnetic property or a ferromagnetic metal thin plate. By using an electromagnet provided behind the base, the mask is adhered to the surface of the base to evaporate the synthetic resin monomer from the evaporation source outlet, and the monomer is polymerized on the surface of the base to form a synthetic resin pattern. It is the one.

A urea resin prepared by a polyaddition reaction is used as a synthetic resin.

Further, an imide resin prepared by a polyaddition reaction and a dehydration condensation reaction is used as a synthetic resin.

Further, a composite film prepared by applying a paint mainly composed of a ferromagnetic material on one or both sides of a plastic film is used as a flexible film having ferromagnetism.

A composite film is a flexible film having a ferromagnetic property in which a layer mainly composed of a ferromagnetic material is formed on one or both sides of a plastic film by vapor deposition or sputtering.

[0011]

According to this method, no foreign matter remains on the surface of the substrate, the patterning process is simple, and the multi-layer film is easily formed by using the "mask method". After a thin mask is set on the surface of the substrate, an electromagnet is installed on the back surface of the substrate and the magnetic force causes the mask to adhere to the entire surface of the substrate. Even in this case, a clear pattern can be formed over the entire surface of the substrate.

The mask material used in the present invention must be flexible enough to follow the warp of the substrate surface and the unevenness of the formed multilayer film surface. It is necessary to select the mask thickness and material characteristics depending on the pattern shape, the size of the warp of the substrate, the thickness of the multilayer film to be formed, and the like. Further, the thin metal plate having ferromagnetism is not sufficiently flexible, so that its application range is limited, but the application is possible. According to this structure, the warp of the substrate surface and the formed multilayer film are possible. Even if the surface of the substrate has irregularities, it is possible to form a clear pattern over the entire surface of the substrate.

[0013]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of an apparatus for forming a pattern of a synthetic resin thin film according to the present invention. As shown in the figure, a substrate 3 for forming a synthetic resin thin film is held downward by a substrate holder 4 in a vacuum chamber 2 connected to a vacuum exhaust system 1. Further, an evaporation source ejection port 5 for evaporating the raw material monomers and an evaporation source ejection port 6 on the other side are provided in the lower portion of the vacuum tank 2, and the evaporation source containers 7 and 8 are heaters (not shown). A predetermined temperature is controlled by a thermocouple (not shown) so that the evaporation rate of the raw material monomer becomes constant. A shutter 9 is provided between the evaporation source ejection ports 5 and 6 and the substrate 3, and the opening and closing of the shutter 9 adjusts the film thickness of the synthetic resin thin film formed on the substrate 3. Further, there is a mask 10 for making a pattern on the substrate 3 in contact with the substrate 3, and an electromagnet 11 is provided on the opposite side of the mask 10 via the substrate 3.

Next, an example of a method for forming a urea resin thin film by a polyaddition reaction using the apparatus shown in FIG. 1 will be described. 10 cm
Square glass plate (Amount of warp: 0.32 to 0.44 mm / 10
0 mm) as the substrate 3, the evaporation source container 7 is filled with 4,4 ′ methylene dianiline, and the evaporation source container 8 is filled with 4,4 ′ diphenylmethane diisocyanate, and the atmosphere gas in the vacuum chamber 2 with the shutter 9 closed. Is evacuated by the vacuum evacuation system 1 until the total pressure of is less than 10 ^-3 Pa. The base 3
The distance from the center point of to the center of the evaporation source ejection ports 5 and 6 is 20 cm, the inner diameter of the evaporation source ejection ports 5 and 6 is 2 cm,
The distance between the evaporation source ejection ports 5 and 6 was 5 cm. The mask 10 used was a composite film in which a coating layer containing pure iron fine particles having a thickness of 4 μm as a main component was formed on a polyethylene terephthalate film having a thickness of 12 μm. Mask 1
After 0 was placed in contact with the surface of the substrate 3, the electromagnet 11 was energized, and the mask 10 was brought into close contact with the substrate 3 by the attraction force of the electromagnet. Then, the heaters of the evaporation source vessels 7 and 8 were controlled to supply 4,4 ′ methylenedianiline to 115
To ± 1 ° C., 4,4 ′ diphenylmethane diisocyanate was heated to 85 ± 1 ° C. 1 in this state
After opening for 20 seconds, both raw material monomers were vapor-deposited on the substrate 3 to form a urea resin film A. At this time, the thickness of the urea resin thin film A was about 1 μm.

For comparison with the example, a urea resin thin film B was prepared as a comparative example by vapor deposition under exactly the same conditions as the example except that the electromagnet 11 was not energized. The thickness of this urea resin thin film B was also about 1 μm.

FIG. 2A shows the film thickness distribution (7-point measurement) at the pattern edge of the urea resin thin film A of this embodiment, and FIG.
Is shown in FIG. The film thickness on the vertical axis in FIG. 2 is shown as a relative value with the maximum film thickness in the substrate being 1. As is clear from FIG. 2B, in the comparative example, the change in the sharpness of the pattern edge occurs due to the change in the gap between the substrate 3 and the mask 10. However, the synthetic resin thin film of the present example in FIG. In the pattern forming method, the change in the gap between the substrate 3 and the mask 10 is extremely small, and a clear pattern can be obtained.

As described above, according to this embodiment, a mask made of a flexible film having a ferromagnetic property or a ferromagnetic metal thin plate is brought into close contact with the substrate surface by the attraction force of an electromagnet to form a pattern. Even when the substrate surface is warped or the multilayer film surface is uneven, it is possible to create a synthetic resin thin film pattern having good definition over the entire surface of the substrate.

[0019]

As is apparent from the above description of the embodiments, according to the present invention, in a method for producing a synthetic resin thin film on a substrate in a vacuum, a flexible film having ferromagnetic property or a ferromagnetic metal. By forming a pattern by bringing a mask made of a thin plate into close contact with the surface of the substrate by the attraction force of the electromagnet, no foreign matter remains on the surface of the substrate, the pattern forming process is simple, and a multilayer film can be easily formed. Further, even when the substrate surface is warped or the formed multi-layer film surface has irregularities, it is possible to create a pattern of a synthetic resin thin film having good definition over the entire surface of the substrate.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a synthetic resin thin film pattern forming apparatus according to an embodiment of the present invention.

FIG. 2A is a diagram showing a pattern edge thickness distribution of the same synthetic resin thin film, and FIG. 2B is a diagram showing a pattern edge thickness distribution of a conventional synthetic resin thin film.

[Explanation of reference symbols] 1 vacuum exhaust system 2 vacuum tank 3 substrate 4 substrate holder 5,6 evaporation source ejection port 7,8 evaporation source container 9 shutter 10 mask 11 electromagnet

Claims (6)

[Claims] 1. A method for producing a synthetic resin thin film on a substrate in a vacuum, wherein a mask made of a flexible film having a ferromagnetic property or a ferromagnetic metal thin plate is provided by an electromagnet provided behind the substrate. A method for forming a pattern of a synthetic resin thin film, which comprises forming a synthetic resin pattern by evaporating a synthetic resin monomer from an evaporation source outlet while closely adhering to the surface of the substrate and polymerizing the monomer on the surface of the substrate. 2. The synthetic resin thin film pattern forming method according to claim 1, wherein the synthetic resin is a urea resin prepared by a polyaddition reaction. 3. The synthetic resin thin film pattern forming method according to claim 1, wherein the synthetic resin is an imide resin prepared by a polyaddition reaction and a dehydration condensation reaction. 4. The pattern formation of the synthetic resin thin film according to claim 1, wherein the flexible film having ferromagnetism is a composite film obtained by applying a coating material mainly composed of a ferromagnetic material on one or both sides of a plastic film. Method. 5. The synthetic resin thin film according to claim 1, wherein the flexible film having ferromagnetism is a composite film in which a layer mainly composed of a ferromagnetic material is formed on one or both sides of a plastic film by vapor deposition or sputtering. How to create a pattern. 6. The synthetic resin thin film pattern forming method according to claim 1, wherein the flexible film having ferromagnetism is a composite film in which a ferromagnetic material is dispersed in a plastic film.