JPS61180437A - Formation of pattern - Google Patents

Abstract

PURPOSE:To form microscopically a pattern by a method wherein sensitive group-containing sensitive thin films are formed, energy lines are irradiated on the sensitive thin films in a pattern form to deactivate the sensitive groups and a pattern-form polymerized film is formed in the vapor of a polymerizable monomer. CONSTITUTION:Unimolecular films 2 are formed on an Si substrate 1 by a chemical absorption process using a silane interface activator. Then, a patterned electron beam 5 is irradiated. By this irradiation, the double bonds of the vinyl groups 4 of the silane interface activator bond to one another and the double bond bonded are deactivated. Then, the substrate 1 is put in the vapor of a polymerizable monomer. Then, far ultraviolet rays 8 are irradiated on the whole surface for a short time. By this irradiation, parts of the sensitive groups, which are not still deactivated, are activated and a monomer is made to addition- polymerize 9 in a pattern form. With this, a thin film pattern 10 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a pattern forming method characterized by selectively forming a film on an arbitrary substrate using a chemical reaction, and is suitable for manufacturing semiconductor devices. It can be used for printing plates, printing plates, etc. Conventional technology Conventionally, in the production of resist turns in the manufacture of semiconductor devices and the production of resin turns, which serve as original plates in the manufacture of printing plates, the polymerization process is carried out by irradiating a substrate with light. A commonly used method is to form a decomposable resin film, irradiate it with light in a pattern, and then develop it to form an arbitrary pattern.

However, these resist and resin patterns are increasingly required to be made finer due to the higher density of semiconductor elements and the higher quality of printed matter.

In particular, in the manufacture of VLSI, it has become necessary to create submicron resist patterns with high precision.

Problems that the invention sought to solve In cases like this, the characteristics of the resist and resin themselves have a large effect, but generally speaking, the more minute and ζ turns are desired, the more
That is, in order to increase the resolution, it was necessary to make the resist coating thinner. On the other hand, when it comes to submicron patterns, wet etching cannot be used and dry etching such as ion etching, plasma etching, or sputter etching must be used. Although it depends on the situation, it is generally necessary to make the resist coating film thick. Therefore, in order to satisfy the above two requirements,
It would be good to develop a photoresist with good resolution even with a thick coating, or a photoresist with good dry etching resistance even with a thin coating, but so far no good photoresist has been obtained.

An object of the present invention is to provide a method for forming a resin pattern with high resolution and excellent etching resistance.

Means to solve problems The present invention uses an energy beam (electron beam) on a substrate.

After forming a sensitive thin film containing sensitive groups that cause a chemical reaction using ion beams, light, X-rays, etc., and selectively inactivating some of the sensitive groups by irradiating them with energy rays in a pattern, Further, the film is moved into a polymerizable monomer atmosphere, and the entire surface is irradiated with energy rays again to cause addition polymerization of the polymerizable monomer to the sensitive thin film other than the pattern irradiated area to form a patterned polymer film. It is.

Furthermore, as a method of forming a sensitive thin film, a monomolecular film may be cumulatively formed using the Langmuir-Prodgett method or the chemisorption method so that the energy ray-sensitive groups are lined up and exposed on the substrate surface. This enabled the formation of ultra-fine patterns as well as improved sensitivity.

Alternatively, after forming the above-mentioned pattern on the substrate via another organic thin film, the pattern is transferred to the organic thin film by etching and removing a part of the underlying organic thin film using the pattern as a mask. It is characterized by its use.

action According to the present invention, it is possible to form ultra-fine patterns.

EXAMPLE Hereinafter, an example of the pattern forming method of the present invention will be described with reference to FIGS. 1 and 2. For example, in the first embodiment shown in FIG. 1, a disilane surfactant, e.g., 0H2=OH-
((H2)n -Si, Cl5 (n is an integer, 10 to 2
o is better, C)! ,, = OH- is CH3CH
- may be used) to form a monomolecular film 2 on the surface of the substrate. For example, 2. OX 10-'~5. OX 10-
8o% n-hexane dissolved at a concentration of 2Mol/l,
12% carbon tetrachloride, 8% chlorophor forming bond 3 (
Figure 1 (2L)) At 1°, the vinyl groups 4 of the silane surfactant are lined up on the substrate surface and formed into a film (Figure 1 (b)).
Moreover, since the electron beam irradiation causes a polymerization reaction between the surrounding vinyl groups, the electron beam 5 is then irradiated in a chisel shape as shown in FIG. 1(C). Then, the first
As shown in Figure (d), the double bonds of the vinyl groups in the portion 6 irradiated with the electron beam bond with each other and are selectively inactivated (deactivated).

Next, as shown in FIG. 1 (θ), a polymerizable monomer 7 such as methyl methacrylate monomer is placed in a vapor of about 1 to 3 torr (others include trimethylvinylsilane, tributylvinylsilane, diallylmethylphenylsilane, styrene, and tetrafluoroethylene). Transfer the substrate to a polymerizable polymer such as acrylonitrile, methacrylic acid, cyclobenzene, vinyltoluene, maleic acid amide, etc.), and irradiate the entire surface with deep ultraviolet light 8 for a short time to sensitize the non-active parts. The groups are activated to cause addition polymerization of monomers in a pattern. In this process, thin film pattern 1
0 will be formed (FIG. 1 (0)).

In the above example, a Si substrate on which a silane surfactant of 18iC15 or 5i02 was formed was used as an example, but other inorganic materials have A/20. , glass, etc., and organic materials such as polyvinyl alcohol can be used. In addition, if the substrate surface is covered with another material that exhibits water repellency, it is necessary to form a Langmuir-Blodgett film and arrange hydrophilic groups all over the substrate surface, or to make the substrate surface hydrophilic by 02 plasma treatment etc. Although the adhesion of Langmuir-Prodgett film is inferior, even if the material on the substrate surface is water repellent, if the accumulation is stopped when the water repellent surface is on the substrate side, , it is possible to make the surface completely new water-based.

Furthermore, when the 0□ plasma treatment is performed, the substrate surface is oxidized and becomes hydrophilic.

Therefore, as shown in FIG.
1 torr, 1 oow, 30 seconds) to form a treated layer 112L, a silane surfactant was adsorbed onto the resist surface using the same method as in the previous example (see FIG. 2). After forming the pattern 10 by performing the same steps as in the above example (FIG. 2(b)), first, the pattern 10 was added to a mask at 021% and subjected to plasma treatment in OF4 gas. If a portion of the sensitive thin film 6 containing Si is selectively removed and then O2 plasma or O2 reactive sputter etching is performed to selectively remove the resist 11, the pattern 1o of the selectively polymerized film is formed into a resist). Can be transferred to 11 (
Figure 2 (C)). In this case, photoresist was used as the organic thin film, but it is clear that any material that can be etched by 02 plasma may be used. In addition, if a monomer containing Si such as trimethylvinylsilane is used as a polymerizable monomer, Si will be contained in the polymerization pattern and SiO□ will be formed against the 02 plasma, so the polymerization film will not need to be very thick. Since sufficient 02 plasma etching resistance can be ensured, there is an advantage that high resolution can be obtained. On the other hand, if you transfer the pattern to photoresist,
Since the thickness of the photoresist can be made sufficiently thick, dry etching (for example, CF to etch Sio2 and Si), which is generally used in the VLSI manufacturing process, can be used.
It can be used as an ultra-fine resist pattern that has sufficient etching resistance even for reactive sputter etching using 4).

In addition, in the above two examples, a method of adsorbing and reacting a silicone surfactant as a sensitive thin film was shown, but in advance, a reagent in which -Cl was replaced with 10H (0H2
= CM - (CH2)n -5i (OH)3 etc.) or w
-1-Licosenoic acid (C; Hz=CH(OH2)z.

C0oH), W-hebutaf senic acid (CH2= OH
-(CH2)14CoOH), acetylene derivatives (C
) It is also possible to form a sensitive thin film by the Langmuir-Prodgett method using a reagent with balanced amphiphilic properties such as I=C(CH2)nC00H).

In addition, in the above-mentioned example, the interfacial reaction between -3i C13 and 10H was shown as an example, but the present invention is not limited to these as long as the substance exhibits a similar reaction mechanism.

Effects of the Invention As described above, if the method of the present invention is used, the energy ray-sensitive thin film during pattern formation is formed from a single layer or several layers of monomolecular cumulative film, so it is possible to form ultra-fine patterns. is possible. Furthermore, if a polymerizable monomer containing Si is used, a polymeric film pattern with high 0□ dry etch resistance can be obtained.

Therefore, if an organic thin film such as a general photoresist is used as the lower layer, the pattern can be easily transferred to the organic thin film by oxygen dry etching.

In addition, the Langmuir-Prodgett method and adsorption method used to form sensitive thin films proceed through an interfacial reaction with the substrate surface, so they are not affected much by substrate height differences and can be used for substrates with many height differences, such as those on VLSI devices. If you do, it will have a big effect. As described above, the method of the present invention is highly effective in improving one step of photolithography in the production of ultra-fine patterns, especially in VLS technology.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the first embodiment of the pattern forming method of the present invention, and (a), (C), (8)
FIG. 2 is a diagram illustrating a process of transferring a pattern to an organic thin film in a second embodiment of semiconductor manufacturing. 1...Substrate, 2...Sensitive thin film, 6,
8...Energy rays, 11...Organic thin film. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 1 ° ′ ” ° “ −l Figure 2 ?

Claims (5)

[Claims] (1) A step of forming a sensitive thin film containing a sensitive group that causes a chemical reaction with energy rays on an arbitrary substrate, and a step of irradiating the sensitive thin film with energy rays in a pattern to make the sensitive groups inactive in a pattern. Then, the substrate on which the irradiated film is formed is moved to an atmosphere of a polymerizable monomer, and the entire surface of the irradiated film is irradiated with energy rays again to cause addition polymerization of the polymerizable monomer on the sensitive thin film other than the pattern irradiated area. A pattern forming method comprising the step of forming a patterned polymer film. (2) In the process of forming the sensitive thin film, a monomolecular sensitive thin film is formed by Langmuir-Prodgett method or adsorption method, etc. so that the sensitive groups are exposed in line on the substrate surface. A pattern forming method according to claim 1. (3) The pattern forming method according to claim 1, characterized in that a substance containing Si is used as the polymerizable monomer. (4) A photosensitive thin film is formed on an arbitrary substrate via an organic thin film, and after selectively forming a patterned polymer film of a material containing Si, Si is removed by treatment with oxygen plasma. 4. The pattern forming method according to claim 3, further comprising transferring a pattern containing the organic thin film onto the organic thin film. (5) The pattern forming method according to claim 1, wherein the sensitive group of the sensitive thin film and the polymerizable group of the polymerizable monomer include a vinyl group or an ethynyl group.