JPH06179958A - Pattern forming method for synthetic resin thin film - Google Patents

Abstract

PURPOSE:To provide a pattern forming method for a synthetic resin thin film free from remaining foreign matters on the surface of a substrate, easy in the working of a multi-ply film in a pattern forming process and having uniform film thickness and the high clarity of the pattern. CONSTITUTION:In the method for forming the pattern of the synthetic resin thin film on the substrate 3 by evaporating one or more kinds of a synthetic resin raw material monomer in vacuum from evaporating source emitting openings 5, 6 to the substrate 3 and using a mask 11 mounted at the direct front of the substrate 3, a cooling plate 10 is arranged between the emitting openings 5, 6 of the synthetic resin raw material monomer and the mask 11 and out of the region made by linking the mask 11 with the emitting openings 5, 6 of the synthetic resin raw material monomer and the pattern of the synthetic resin thin film is formed on the substrate 3. By this method, reevaporating components generated from other than the evaporating source are removed and the clear pattern of the synthetic resin thin film is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a pattern of a synthetic resin thin film used for an insulating film of a semiconductor device or an electrostatic chuck, a passivation film, a soft error film, a dielectric of a plastic capacitor and the like.

[0002]

2. Description of the Related Art Conventionally, there are the following three methods for patterning a synthetic resin thin film in a vacuum.

The first method is to form a negative image on the surface of a substrate by silk screen printing, photoresist or the like, form a necessary synthetic resin thin film on the whole surface, and then form a negative image with an organic solvent or the like. This is a "lift-off method" in which only the material is melted and the unnecessary portion of the synthetic resin thin film is removed to form a pattern.

In the second method, a synthetic resin thin film is entirely formed on the surface of the substrate, and then a positive image is formed by silk screen printing or photoresist, and then the synthetic resin thin film on the exposed portion is wet-etched or dry-etched. It is a "photo-etching method" in which the pattern of the synthetic resin thin film is obtained by removing the positive image-forming material only with an organic solvent or the like and dissolving it.

The third method is a "mask method" in which a substrate adhered to a negative pattern mask is exposed to vapor of a synthetic resin raw material monomer to obtain a pattern of a synthetic resin thin film.

[0006]

However, in the above-mentioned conventional method for forming a pattern of a synthetic resin thin film in a vacuum, in the case of the first "lift-off method", it is difficult to obtain a clear pattern, and foreign substances are not formed on the surface of the substrate. There were problems such as remaining. Further, in the case of the second "photoetching method", there is a problem that the pattern forming process is complicated and it is difficult to process the multilayer film. In the case of the third "mask method", the pattern forming process is simple and can be performed only by the dry process, and the processing of the multilayer film is easy.
Although it is superior to the second method, there are problems that it is difficult to obtain a clear pattern unless the distance between the base and the mask is minimized and that the base is scratched when the base and the mask are in strong contact with each other. Had.

Therefore, in the third "mask method", it is proposed to use a plurality of masks provided at intervals. However, with this method, thin film formation outside the pattern edge is reduced and the pattern edge becomes clear, but the film thickness inside the pattern edge becomes uneven due to the shadow of the mask, as in the case of using a thick mask. It was found that a synthetic resin thin film having a uniform film thickness and a clear pattern could not be obtained.

The present invention solves the above-mentioned conventional problems. No foreign matter remains on the surface of the substrate, the pattern forming process is simple, the processing of the multilayer film is easy, and the film thickness is uniform and the sharpness of the pattern is high. It is an object of the present invention to provide a high synthetic resin thin film pattern forming method.

[0009]

In order to achieve the above object, a method for forming a pattern of a synthetic resin thin film according to the present invention comprises a mask placed immediately before a substrate by evaporating at least one synthetic resin raw material monomer in a vacuum. In the method of forming a pattern of a synthetic resin thin film on a substrate by means of, a cooling plate is installed between the ejection port of the synthetic resin raw material monomer and the mask.

[0010]

The inventors of the present invention have variously studied why, in the mask method, which is one of the methods for forming a pattern of a synthetic resin thin film in a vacuum, a clear pattern cannot be obtained unless the distance between the substrate and the mask is reduced. As a result, the following points became clear.

Of the synthetic resin raw material monomers evaporated from the ejection port, those other than those that directly reach the substrate adhere to the inner wall of the vacuum chamber heated by the radiant heat from the evaporation source, etc., and re-evaporate. It reaches the substrate at the angle of incidence. That is, it was found that the monomer component that reached the substrate at a large incident angle entered through the gap between the substrate and the mask, and the sharpness of the pattern was lost.

Therefore, according to the method of the present invention, if a cooling plate is installed between the jet of the synthetic resin raw material monomer and the mask, the evaporative components other than the synthetic resin raw material monomer that reach the substrate directly from the jet outlet are the cooling plate. The monomer component reaching the substrate with a large incident angle is removed by the above. In this case, if this cooling plate is installed outside the region where the spout of the synthetic resin raw material monomer and the mask are connected by a straight line, the portion where the film thickness becomes thin due to the shadow of the cooling plate does not occur on the substrate.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic sectional view of an apparatus for forming a synthetic resin thin film used to carry out the present invention. As shown in FIG. 1, a substrate 3 for forming a synthetic resin thin film is held downward in a vacuum chamber 2 connected to a vacuum exhaust device 1 by a substrate holder 4 having a cooling function (not shown). To be done. In the lower part of the vacuum chamber 2, ejection ports 5 and 6 for ejecting the synthetic resin raw material monomer are provided, and evaporation source containers 7 and 8 connected to them are a heater (not shown) and a thermocouple (not shown). Thus, the synthetic resin raw material monomers are controlled so as to be maintained at predetermined temperatures. A shutter 9 is provided immediately after the ejection ports 5 and 6, and the film thickness formed on the substrate 3 is adjusted by opening and closing the shutter 9. Further, a negative pattern-shaped mask 11 is provided immediately before the base body 3,
A cooling plate 10 having a cooling function (not shown) is installed between the mask 11 and the ejection ports 5 and 6 and outside the region where the both are connected by a straight line.

Next, a method for forming a pattern of a urea resin thin film by a polyaddition reaction using the above apparatus will be described.

Example 1 Substrate 3 which is a 10 cm square glass plate
And a mask 11 having a plate thickness of 0.1 mm are held at an interval of 0.1 mm. In the evaporation source container 7, 4,4'methylene.
200 g of dianiline (hereinafter, abbreviated as MDA) is added to the evaporation source container 8 as 4,4'diphenyl methane diisocyanate (hereinafter, abbreviated as MDI) 250 which is one kind of diisocyanate.
g, and the total pressure of the atmosphere gas in the vacuum chamber 2 is 1 × 10 to ³
The gas is exhausted by the vacuum evacuation device 1 until it becomes Pa or less. The distance from the center point of the substrate 3 to the centers of the ejection ports 5 and 6 is 20 cm, the inner diameter of the ejection ports 5 and 6 is 2 cm, and the distance between the ejection ports 5 and 6 is 3 cm.

Next, the heaters of the evaporation source vessels 7 and 8 were controlled to heat MDA to 110 ± 0.5 ° C. and MDI to 85 ± 0.5 ° C. In this state, the shutter 9 is opened for 120 seconds and the vapors of both raw material monomers are directed onto the substrate 3 to give a thickness of 1 μm.
A pattern of m urea resin film A (synthetic resin thin film) was obtained. The substrate holder 4 and the cooling plate 10 were cooled to 10 ° C.

(Comparative Example 1) FIG. 2 is a schematic sectional view of an apparatus for forming a synthetic resin thin film used for comparison with the above-mentioned embodiment, and the cooling plate 10 in FIG. 1 is omitted. A urea resin film B (synthetic resin thin film) pattern was obtained in exactly the same manner as in Example 1 except that the apparatus shown in FIG. 2 was used.

(Comparative Example 2) FIG. 3 is a schematic cross-sectional view of a synthetic resin thin film forming apparatus used for comparison with the above-mentioned embodiment. The cooling plate 10 shown in FIG.
It was changed to a region where 6 and 6 were connected by a straight line. The urea resin film C was prepared in the same manner as in Example 1 except that the apparatus shown in FIG. 3 was used.
A pattern of (synthetic resin thin film) was obtained.

The thickness distribution of the pattern edge portion of the urea resin film A obtained in this example is shown in FIG. 4 (A), and the thickness distribution of the pattern edge portion of the urea resin film B obtained in Comparative Example 1 is shown. Figure 4
Each is shown in (B). However, the film thickness is shown as a relative value with the maximum film thickness of the obtained synthetic resin thin film as 1. As is clear from FIGS. 4 (A) and 4 (B), although the sharpness of the pattern edge is inferior in Comparative Example 1, a clear pattern is obtained by the pattern forming method of the synthetic resin thin film of this Example. . Further, as is clear from FIG. 3, although the urea resin film C obtained in Comparative Example 2 has a clear pattern in the center of the substrate 3, the peripheral portion of the substrate 3 falls into the shadow of the cooling plate 10 and therefore has a predetermined composition. No resin thin film was obtained.

As described above, according to this embodiment, by installing the cooling plate between the mask and the ejection port and outside the region where the mask and the ejection port are connected by a straight line,
It is possible to form a synthetic resin thin film having a uniform film thickness and a high pattern definition. In other words, unlike vacuum metal deposition, the synthetic resin raw material monomer, which is an organic substance, evaporates again even if it adheres once if the temperature in situ is high. It is necessary to remove the re-evaporated components with a trap provided by a cooling plate.

In the examples, the case where the urea resin is formed as the synthetic resin by using the diamine and diisocyanate is shown. However, the synthetic resin is the above diamine and 3,3'-4,
4'benzophenone tetracarboxylic acid dianhydride (BTD
It goes without saying that a polyimide resin may be prepared by using an acid dianhydride such as A).

Although it is unclear in the sectional view of FIG. 1,
It goes without saying that the shape of the cooling plate can be selected from a cylindrical shape and a rectangular tube shape.

[0024]

As described above, according to the method for forming a pattern of a synthetic resin thin film of the present invention, one or more kinds of synthetic resin raw material monomers are evaporated in a vacuum, and a synthetic resin thin film is synthesized on a substrate by a mask installed immediately before the substrate. In the method of forming the pattern of the resin thin film, by installing the cooling plate between the ejection port of the synthetic resin raw material monomer and the mask and outside the region where the mask and the ejection port are connected by a straight line, foreign substances are not formed on the substrate surface. It is possible to realize a method for forming a pattern of a synthetic resin thin film in which the pattern forming process is simple, the multilayer film is easily processed, and the film thickness is uniform and the pattern definition is high.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of an apparatus used to carry out a method for forming a pattern of a synthetic resin thin film according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of an apparatus used for carrying out a method for patterning a synthetic resin thin film in a comparative example of the present invention.

FIG. 3 is a schematic cross-sectional view of an apparatus used for carrying out a method for forming a pattern of a synthetic resin thin film in a comparative example of the present invention.

FIG. 4 is a film thickness distribution diagram of pattern edges of synthetic resin thin films of Example (A) and Comparative Example (B) of the present invention.

[Explanation of Codes] 1 ... Evacuation device, 2 ... Vacuum tank, 3 ... Substrate, 4 ...
Substrate holder, 5, 6 ... Spouting outlet, 7, 8 ... Evaporation source container, 9 ... Shutter, 10 ... Cooling plate, 11 ... Mask.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication location H05K 3/14 A 7511-4E (72) Inventor Masayuki Iijima 2500 Hagien, Chigasaki City, Kanagawa Japan Vacuum Technology Incorporated (72) Inventor Yoshikazu Takahashi 2500 Hagien, Chigasaki City, Kanagawa Japan Vacuum Technology Co., Ltd.

Claims (4)

[Claims] 1. A method for forming a pattern of a synthetic resin thin film on a substrate by evaporating one or more kinds of synthetic resin raw material monomers in a vacuum and using a mask installed immediately before the substrate,
A method for forming a pattern of a synthetic resin thin film, characterized in that a cooling plate is installed between the ejection port of the synthetic resin raw material monomer and the mask. 2. The method for forming a pattern of a synthetic resin thin film according to claim 1, wherein a cooling plate is provided outside the region where the ejection port of the synthetic resin raw material monomer and the mask are connected by a straight line. 3. The pattern forming method for a synthetic resin thin film according to claim 1, wherein the synthetic resin raw material is a urea resin formed by a polyaddition reaction of diisocyanate and diamine. 4. The method for forming a pattern of a synthetic resin thin film according to claim 1, wherein the synthetic resin raw material is a polyimide resin formed by heating polymerization of diamine and acid dianhydride.