JPS62288822A - Resist for lithography - Google Patents

Abstract

PURPOSE:To improve the effective sensitivity of a resist for lithography, by respectively causing layers containing a photosensitive material and fluorescent material to contain the single molecular film or a laminated film of single molecular films of organic compounds containing the photosensitive material and fluorescent material. CONSTITUTION:The titled resist has a characteristic of being composed of a layer 24 containing a photosensitive material to be exposed to irradiation energy and a layer 25 containing a fluorescent material which emits fluorescent rays, to which the photosensitive material is exposed, when the fluorescent material is exposed to irradiation energy. Moreover, the layers 24 and 25 respectively contain a single molecular film or a laminated film of single molecular films containing the photosensitive material and fluorescent material. When such resist is projected with principal light beams through a mask, the resist is exposed to the principal light beams transmitted through the mask and fluorescent rays emitted from the fluorescent material exposed to the principal light beams. As a result, the effective sensitivity of the resist is improved.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a resist for lithography, and in particular, the present invention relates to a resist for lithography, and in particular, a resist that contains a fluorescent substance and increases effective sensitivity by using a monolayer accumulation method. The present invention relates to resists for lithography.

[Conventional technology]

X-ray lithography has many advantages over conventional lithography using visible light or ultraviolet light, based on the inherent properties of X-rays such as straightness, non-coherence, and low diffraction. Therefore, in recent years, it has attracted attention as a powerful means for submicron lithography and crystallographic lithography.

(Problems to be solved by the invention) However, although X-ray lithography has many advantages over phosphorography using visible light or ultraviolet light, it suffers from insufficient power of the X-ray source, low sensitivity of the resist, and The productivity is low due to difficulties in manufacturing, selection of mask materials, and processing methods, and therefore, the cost is high, and practical application has been delayed.

By the way, polymethyl methacrylate (PMMA) can be cited as the most practical resist that has been introduced in literature related to lithography. This resist has a proven track record as an electron beam resist, and there is no other product that can compete with it, especially as one that can handle resists of 0.1- or less. However, a major problem in X-ray lithography that remains is that of sensitivity. Normally, the X-ray utilization efficiency of a resist in X-ray lithography is said to be 0.3% or less. For example, in the case of PMMA, if alpha rays are used for Pd as X-rays, the effective sensitivity is 1000 to 2000 mJ/cr.
Here, sensitivity is indicated by the amount of X-ray irradiation during exposure. In other words, the lower the amount of irradiation, the higher the sensitivity. Chloromethylated polystyrene (CMS, (manufactured by Toyo Soda), but its effective sensitivity under the same conditions as above is approximately 100 mJ/crn'.One of the conditions for the practical use of x11A lithography is to increase the effective sensitivity of the X-ray resist to 10 mJ/crn'. The following is desired, and the appearance of such an X-ray resist is awaited.

Research is currently underway in various fields to increase productivity from three directions: powering up radiation sources, X-ray masks with good transparency, and high-sensitivity resists, but many limiting factors prevent major progress from happening quickly. I don't think I can hope for that. However, among these, improving the sensitivity of the resist is a necessary condition from the viewpoint of damage caused to devices by X-rays. It goes without saying that this will be necessary and indispensable even if the performance of masks and radiation sources improves in the future.

[Purpose of the invention]

SUMMARY OF THE INVENTION In view of the problems of the prior art described above, it is an object of the present invention to provide a lithography resist with increased effective sensitivity, thereby allowing lithography to be performed satisfactorily.

[Means for solving problems]

The above objects of the present invention are achieved by the present invention as follows. That is, the present invention has a layer containing a photosensitive material that is sensitized to irradiation energy, and a layer containing a fluorescent substance that generates fluorescent rays that sensitize the photosensitive material when exposed to the irradiation energy. and a resist for lithography, characterized in that the layer containing the photosensitive material and the layer containing the fluorescent substance each include a monomolecular film of an organic compound containing a photosensitive material and a fluorescent substance, or a cumulative film thereof. be.

Specifically, the present invention provides a layer containing a fluorescent substance that emits fluorescent rays that sensitize the photosensitive material when exposed to principal rays such as X-rays and light wavelength ranges. (100 mμ to 700 mμ), and is formed by laminating a layer containing a photosensitive material and a layer containing a fluorescent substance by a monolayer deposition method. It is. When such a resist is irradiated with a main line through a mask, the resist becomes sensitized by the main line transmitted through the mask and the fluorescent light emitted from the fluorescent substance exposed to the main line, increasing the effective sensitivity.

The photosensitive material used in the present invention may be any photosensitive material for lithography that is sensitive to main rays such as X-rays and is sensitive to the light wavelength range emitted by the fluorescent substance contained in the resist. Available for use. For example, xH as the main line
When using X-rays, it is possible to use one that is sensitive to visible light, ultraviolet rays, far ultraviolet rays, or vacuum ultraviolet rays as well as X-rays. Even if the characteristic absorption range of the resist polymer itself is outside the above-mentioned common range, it can be applied to the present invention by widening the absorption range with a wavelength sensitizer.

Typical photosensitive materials that can be used in the present invention include quinone azide/phenol novolak resist, polymethyl methacrylate (PMMA), % resist, polymethyl isopropenyl ketone (PMIPK) resist, and polycinnamic acid (PVAC) resist. ) type resist, cyclized rubber/bisazide type resist, chloromethylated polystyrene (CMS) type resist, polyvinylcarbazole (P
VK) type resists, diacetylene derivatives, etc.

In order to form a layer containing a photosensitive material by the monolayer deposition method, it is preferable to use a molecule having both a hydrophilic site and a hydrophobic site within the molecule.

For example, a diacetylene derivative compound represented by the general formula (1) can be mentioned.

R-CEC-CEC-(R1)n-X
(1) R, RI: a aqueous site Condensed polycyclic phenyl groups such as, chain polycyclic phenyl groups such as biphenyl and terphenyl,
Examples of hydrogen atoms and other nonpolar groups, RI include alkylene groups, phenylene groups, etc., and those in which the sum of the number of carbon atoms of R and R are 10 to 30 are particularly preferred.

Examples of the hydrophilic moiety X include carboxyl groups and their metal salts or amine salts, sulfonic acid groups and their metal salts or amine salts, sulfamide groups, amide groups, amino groups, imino groups, hydroxy groups, quaternary amino groups, Oxyamino group, diazonium group, guanidine group, drazine group, phosphoric acid group, silicic acid group, aluminate group, nitrile group,
Examples include thioalcohol groups and other polar groups.

In the present invention, in order to further increase the effective sensitivity, a transition metal that emits fluorescent light is preferably included in the layer containing the photosensitive material. Examples of transition metals used include chromium, manganese, iron, cobalt, nickel, copper, zinc, and cadmium, but manganese is particularly preferred in terms of high sensitivity. These transition metals may exist in the form of ions, complexes, or salts in the layer containing the photosensitive material. Also, the location in the layer does not matter.

FIG. 1(b)(C) is a schematic diagram showing an example of a photosensitive material used in the present invention.

In the figure, a photosensitive compound 1 consists of a hydrophilic site 2, a hydrophobic site 3, and a photosensitive site 4, preferably a transition metal 5.
It may contain.

FIG. 1(a) is a cross-sectional view of a lithography resist of the present invention provided on a substrate, in which a photosensitive compound 1 is laminated on a substrate 7, and a layer 6 containing a fluorescent substance is formed on top of the photosensitive compound 1. It is layered.

The layer containing the photosensitive material in the present invention is created using a monomolecular cumulative film in order to obtain high density and high orderliness of the created film.

As a method for producing a monomolecular film or a cumulative film thereof having such high orderliness and orientation of molecules, for example, the Langmuir-Prodgett method (hereinafter referred to as LB method) developed by Langmuir et al. is used.

In the LB method, for example, in a molecule with a structure that has a hydrophilic site and a hydrophobic site, when the balance between the two (balance of amphiphilicity) is maintained appropriately, the molecule forms a parent tree group on the water surface. This is a method of creating a monomolecular film or a cumulative film thereof facing downward.

A monolayer on the water surface has the characteristics of a two-dimensional system.

When the molecules are sparsely spread, the area per molecule is A
T stands in the two-dimensional ideal gas equation, nA=, between and the surface pressure n “P?L?I2”? Here, K is Boltzmann's constant and T is absolute temperature.

If A is made sufficiently small, the intermolecular interaction becomes stronger, resulting in a two-dimensional solid "condensation film (or solid film)". The condensed film can be transferred layer by layer onto the surface of carriers of various materials and shapes, such as glass substrates.

A specific method for producing a monomolecular film or a cumulative film thereof of diacetylene derivative compound 1 constituting the layer containing the photosensitive material used in the present invention using this method will be described below with reference to FIG.

First, the desired diacetylene derivative compound 1 is dissolved in a volatile solvent such as benzene or chloroform.

This solution of diacetylene derivative compound 1 is spread on an aqueous phase 9 in a water tank 8 to form a film.

Next, in order to prevent this spread layer from freely diffusing on the aqueous phase 9 and spreading too much, a partition plate (or floating '7') In is provided to limit the spread area and control the aggregation state of the film material. , obtain a surface pressure n proportional to its collective state.

By moving the partition plate 10, the developed area can be reduced to control the aggregation state of the film material, gradually increasing the surface pressure, and setting a surface pressure opening suitable for producing a cumulative film.

Gently clean the carrier (substrate) while maintaining this surface pressure.
11 is vertically raised and lowered, a monomolecular film of the diacetylene derivative compound is transferred onto the carrier (substrate) Il.

A monomolecular film of a diacetylene derivative compound is produced as described above, and by repeating the above operation, a cumulative film of a desired cumulative number of monomolecular films of a diacetylene derivative compound is formed.

The diacetylene monomolecular film can be transferred onto the carrier 11 by methods such as the horizontal deposition method and the rotating cylinder method, in addition to the vertical dipping method described above.

The horizontal attachment method is a method in which the carrier (substrate) 11 is brought into horizontal contact with the water surface and transferred, and the rotating cylinder method is a method in which a cylindrical carrier is rotated on the water surface and transferred onto the carrier surface.

In the vertical dipping method described above, the carrier 11 whose surface is hydrophilic is
When the diacetylene derivative compound is lifted out of the water in a direction across the water surface, a diacetylene monomolecular film is formed on the carrier with the hydrophilic sites 2 of the diacetylene derivative compound facing the carrier side.

When the carrier is moved up and down as described above, the diacetylene m molecular film is laminated one layer at each step.

In this case, since the direction of the film-forming molecules is reversed in the pulling process and the dipping process, according to this method, a Y-shaped film is formed between each layer in which the hydrophilic part 2 and the hydrophobic part 3 of the diacetylene derivative compound face each other. Ru.

On the other hand, in the horizontal deposition method, a diacetylene monomolecular film is formed on the carrier with the hydrophobic site 3 of the diacetylene derivative compound 1 facing the carrier side.

In this method, there is no change in the orientation of the film-forming molecules even if they are accumulated, and an X-shape is formed in which the hydrophobic sites 3 face the carrier side in all layers. On the contrary, a cumulative film in which the hydrophilic sites 2 in all layers face the carrier side is called a type 2 film.

The method of transferring the monomolecular layer onto the carrier is not limited to these methods, and when using a large-area carrier, a method of extruding the carrier from a carrier roll into an aqueous phase may also be used. Furthermore, the directions of the hydrophilic sites and hydrophobic sites described above toward the carrier are in principle, and can be changed by surface treatment of the carrier.

In the present invention, if a transition metal is contained in the monomolecular film or the cumulative film of the photosensitive material, the effective sensitivity of the resist will further improve because the transition metal emits fluorescence. Methods for incorporating a transition metal into a monomolecular film of a photosensitive material or a cumulative film thereof include: 1. A method of forming a film using a transition metal salt of a photosensitive material; 2. A method of forming a film using a transition metal salt of a photosensitive material; 2. Preparing a solution containing a transition metal in an aqueous phase. 3. Photosensitivity There are methods such as creating a monomolecular cumulative film of the material and then immersing the cumulative film in a solution containing a transition metal, and whichever method is used, the object of the present invention can be achieved.

Various solid materials such as glass, plastic, paper, and metal can be used as the substrate or carrier for forming the resist of the present invention, and in particular, a silicon wafer or a silicon wafer having an aluminum vapor-deposited film or a chromium-deposited film on its surface is used. etc. are preferably used.

The thickness of the layer containing the photosensitive material used in the present invention varies depending on its use, but is generally about several tons to several micrometers, preferably 100 to 5,000 layers.

Next: Representative examples of fluorescent substances used in the present invention include the following.

2nS:Ag.

ZnS: Cu, AI.

Zn25in4:Mn, CaWO4, Ca2 MgS i207: Ce, ZnO: Zn.

ZnS: Cu, Y2O2S:Tb, Y25i05: Ce.

YAlO3: Ce, Ag.

ZnS: Ag, Ga, CI, ZnS: Zn+I n7 o3, BaSi205: Pb, (Sr, Ca) B407: Eu", Ca2 B50g C1: Eu", Sr,, Si30B CI,: Eu", BaMgA11
4023:Eu'', BaO-6A1203:Mn.

BaSO4:Pb.

La202 S: Tb.

Gd2o2S: Tb, MgB4o, :Tb.

Li2 B407: Cu.

Ba2 Si205: Pb.

NaI: Tl, CaF2: Eu.

MgF2: Eu.

KCI:Tl, CaS: Bi.

acasi03: Pb, βCaSiO3: Pb, BaSi205: Pb, Zn25i04: Ti, Cao-MgO-2Si02: Ti, Ca3 (
PO4)2: Ce, Ca3 (PO4)2: Ce-Mn, Ca3
(PO4)2 :Tl, gWO4 These may be used alone or as a mixture of two or more. Note that the colon in the chemical formula of the fluorescent substance is a symbol to indicate that the element or ion on the right side of the colon is an additive.

In order to form a layer containing a fluorescent substance using a monomolecular cumulative film using the above-mentioned fluorescent substance, the above-mentioned fluorescent substance is dissolved and dispersed in an aqueous phase together with a substance forming a monomolecular film. A method such as transferring it to a substrate is used. In general, the molecules of the substance forming the monomolecular film are preferably compounds having at least one hydrophilic site and one hydrophobic site within the molecule.

Examples of the aqueous portion of the L wiring include the same ones as the hydrophobic portion R described above.

Examples of the above-mentioned hydrophilic site include the same ones as the above-mentioned hydrophilic site X.

Examples of molecules having a hydrophilic site and a hydrophobic site as described above include long-chain fatty acids such as stearic acid and alaxic acid.

The layer containing a fluorescent substance in the present invention is produced using a monomolecular cumulative film in order to obtain high density and high orderliness of the produced film.

In the present invention, the method of forming a layer containing a fluorescent substance is not limited to the method of using a fluorescent substance as described above, but the layer may include a transition metal that emits fluorescent light that sensitizes a photosensitive material. It's okay.

A method for creating a layer containing a fluorescent substance by containing a transition metal in a monomolecular film or a cumulative film thereof is a method of containing a transition metal in a monomolecular film or a cumulative film thereof of the photosensitive material described above. A similar method is used.

FIG. 1(d) is a schematic diagram of a layer containing a fluorescent substance in which the single molecule is a transition metal salt and the molecule itself is a fluorescent substance. A single molecule 6 of a fluorescent substance in the figure consists of a hydrophobic site 3, a hydrophilic site 2, and a transition metal 5.

The transition metal in the layer containing the fluorescent substance is the same as that in the layer containing the photosensitive material described above.

When performing lithography using the lithography resist of the present invention, particularly effective irradiation energy includes X-rays, but γ-rays, vacuum ultraviolet rays, far ultraviolet rays,
Fluorescent rays can also be generated by ultraviolet rays, electron beams, ion beams, etc., and a sensitizing effect can be obtained. These wavelength ranges are not particularly limited, but for example, when using X-rays as irradiation energy, a fluorescent substance that emits fluorescent rays in a wavelength range corresponding to the photosensitive range of the photosensitive material for X-ray lithography is added to the photosensitive material. It is necessary to contain it. Generally, for X-ray lithography, a wavelength range of 1 to 400, preferably 4 to 20, can be suitably used.

Next, the operation of the present invention will be described. When the lithography resist of the present invention is applied to X-ray lithography, it is only the X-rays that project the pattern onto the resist, and the fluorescent light only serves to enhance the effective sensitivity of the resist.

In other words, the present invention is based on the characteristic of a resist that it is hardly sensitized when irradiated with an irradiation energy below a threshold value and becomes sensitized once the threshold value is exceeded. It is used. Therefore, the output of the main line for projecting a pattern need only exceed a threshold value when combined with the fluorescent rays, and conversely, the energy amount of the fluorescent rays must be below a predetermined threshold value so as not to reduce the resolution of the resist. It won't happen. Further, this threshold value varies depending on the type and thickness of the resist, the wavelength range of the fluorescent light, etc., and cannot be unambiguously determined, but it can be determined experimentally if these conditions are determined.

Next, a lithography method using the lithography resist of the present invention will be described with reference to the drawings.

FIG. 3 is a schematic diagram showing an example of an exposure apparatus to which the lithography resist of the present invention is applied. In the same figure, 1
9 is an X-ray source, 20 is a mask frame, and 21 is a mask pattern made of, for example, gold. Further, 22 is an X-ray transparent film (mask material holding thin film) made of polyimide or the like, 23 is a wafer, 24 is a resist, and 25 is a fluorescent substance. In the figure, X-rays generated from an X-ray source (target) 19 are irradiated onto a resist 24 through a mask pattern 21.

At this time, fluorescent light is emitted from the fluorescent material 25 exposed to x, 1!1, so the resist 24 is patterned by the X-rays that have passed through the mask and the fluorescent material and the fluorescent light emitted from the fluorescent material 25. be projected.

(Example) Next, the present invention will be specifically explained based on examples.

Example 1 Manganese chloride tetrahydrate was added 1x in pure water as the aqueous phase lO.
Dissolve at a concentration of 1O→M, and further add 5 potassium hydrogen carbonate.
The solution was dissolved to a concentration of x 10'M and the pH was adjusted to 6.4. Furthermore, the water temperature was controlled to be maintained at 20°C.

Next, as a photosensitive material, a diacetylene derivative compound represented by the following formula:
O0)I was dissolved in chloroform at a concentration of 1×10 −3 M, and 200 JJJ of the solution was spread on aqueous phase 9.

After the solvent chloroform was removed by evaporation, the partition plate 16 was moved to increase the surface pressure to 20 mN/m. As the substrate 11, an antimony-doped n1 type silicon wafer (resistance value 0.010 to 0.011 Ωcm') was used after removing the surface oxide film with hydrofluoric acid. Gently move the substrate 12 up and down in the direction across the water surface at a vertical speed of 10 mm/ff1 inch,
A monomolecular cumulative film of layers was formed.

When the monolayer on the aqueous phase is transferred onto the substrate, the surface pressure of the monolayer on the aqueous phase decreases. Therefore, in order to keep the surface pressure constant, the surface pressure paper 1 provided near the substrate 11 must be
3 and a surface blood pressure monitor 15 connected by a suspension thread 14, the surface pressure is monitored, and the partition plate IO is moved via a control circuit system 16.

As a result of measuring the monomolecular cumulative film formed by the above method by X-ray scattering and atomic absorption spectrometry, it was found that the cumulative film had a layered structure in which the thickness of one layer was 31. It was confirmed that it was incorporated as a carboxylate.

The photosensitive thin film thus formed on the substrate was air-dried for 24 hours to create a layer containing a photosensitive material.

Next, dissolve 113 (CH,) , (:00) 1 in araxic acid represented by the following formula in chloroform at a concentration of lX10-3M, and add 200μ of the solution.
was developed on aqueous phase 9.

After the solvent chloroform was removed by evaporation, the partition plate IO was moved to increase the surface pressure to 20+nN/m. A silicon substrate coated with the photosensitive layer as the substrate 11 was gently moved up and down in the direction across the water surface at a vertical speed of 10 mm/min to form a monomolecular cumulative film of 30 layers, which was used as the layer 6 containing a fluorescent substance.

Next, after pattern irradiation with X-rays (RhLα), prescribed development and rinsing were performed to form a resist pattern.

As a result, with conventional methods such as spinner coating and vapor deposition, 80% residual film was obtained after about 30 minutes of irradiation, but according to the present invention, similar results were obtained in about 6 minutes of irradiation. I found out that I can get it.

In the case of this example, the transition metal is incorporated into the layer 1 containing the photosensitive material, and fluorescence is also generated from within the layer containing the photosensitive material, which seems to improve the sensitivity. .

Example 2 Using pure water as the aqueous phase 9, potassium hydrogen carbonate was mixed with 5XIO
'M was dissolved.

Next, as a photosensitive material, a diacetylene derivative compound represented by the following formula: Manganese salt of 2,4-tricosadecacyuic acid (4BH37-C=(neeC=C=C-C00)2 was dissolved in chloroform at 1×10 The solution was dissolved at a concentration of -3M, and 200 #LL of the solution was spread on the aqueous phase 9, and the surface pressure was increased to 30 mN/m by moving the partition plate !0.

Using a silicon wafer on which 1,500 layers of aluminum were deposited as the substrate 12, a 30-layer monomolecular cumulative film was obtained under the same conditions as in Example 1 to form a layer 1 containing a photosensitive material.

Next, replace the aqueous phase with pure water, dissolve lead salt of stearic acid (CH3(Cl(2),6Coo)2Pb as a fluorescent substance in chloroform at a concentration of 1X10-3M, and add 200μ of the solution.
is spread on the water phase 8, and the surface pressure is increased to 20% by moving the partition plate 9.
It was increased to mN/m. Using the substrate on which the photosensitive layer was formed as the substrate IO, a 30-layer monomolecular cumulative film was obtained to form a layer 6 containing a fluorescent substance.

Next, after pattern irradiation with X-rays Pd (L), a predetermined development process was performed to form a resist pattern.

As a result, the exposure amount of approximately +00 mJ/ctn'' was 5.
It was found that although a resist pattern with 0% residual film could be formed, according to the present invention, a good pattern could be formed at about 1/3 of that, 35 mJ/cm'.

Example 3 As the aqueous phase 9, an aqueous cadmium chloride solution of 1×1O″M was used, and sodium hydrogen carbonate was further dissolved therein to give a concentration of 5×1O′M.

Next, as a photosensitive material, a diacetylene derivative compound represented by the following formula + 22.24-pentacosacyitic acid HC30-GE (nee C2゜H4゜-) was prepared by dissolving OOH in chloroform at a concentration of lX10-3M. The surface pressure was increased to 40 mN/m by moving the partition plate 11.

5i02 of 1000 people by thermally oxidizing the surface as the substrate 12
A film was formed using a silicon wafer in the same manner as in Example 1, and then immersed in a manganese aqueous solution and left for one hour. After drying, the monomolecular cumulative film was measured by atomic absorption spectrometry.
It was confirmed that cadmium in the film was replaced with manganese.

Using pure water as the aqueous phase 9, behenic acid el+3(CH2)2°C0OH was dissolved in chloroform at a concentration of 1X10-3M, and the surface pressure was increased to 20 mN/m by moving the partition plate IO. A 30-layer monomolecular cumulative film was formed on the substrate 11 coated with the photosensitive layer 1, and then immersed in a manganese chloride aqueous solution and left for one hour. After drying, the monomolecular cumulative film was measured by atomic absorption spectrometry, and it was confirmed that manganese was incorporated into the film. This was used as a layer 6 made of a fluorescent substance and used as a resist for lithography.

Next, after pattern exposure using X-rays (α for Al),
A resist pattern was formed by performing a prescribed development process.

As a result, it was found that a good resist pattern could be formed in one minute with about 1/3 the exposure dose compared to that obtained by conventional methods such as spinner coating or vapor deposition.

Example 4 Pure water was used as the aqueous phase 9, and ω-tricosenic acid (CH2-CH((:H2) 20 (:0O)
1) was developed as a 1×10 −3 M chloroform solution on an aqueous phase, compressed to 20 niN/m, and 30 layers were accumulated on a silicon substrate 11 to form a layer 1 containing a photosensitive material.

Next, using zinc araxinate as a fluorescent substance, 20 layers were accumulated in the same manner as described above, and 6 layers containing the fluorescent substance were stacked.
And so.

Next, after pattern exposure using X-rays (CuL rays),
A resist pattern was formed by performing a prescribed development process, and the remaining film was measured.

As a result, even if conventional methods such as spinner coating and vapor deposition require an exposure of 200 mJ/ctn', the present invention provides an exposure of approximately 50 mJ/crn'.
The same film thickness could be obtained with an exposure dose of .

(Effects of the Invention) As explained above, when lithography is performed using the lithography resist of the present invention, the fluorescent substance present in the resist is exposed to irradiation energy to generate secondary irradiation radiation, Since the resist is exposed to both the secondary irradiation radiation and the irradiation energy, the effective sensitivity of the resist is improved and good lithography can be performed. In addition, lithography can be performed by relaxing strict conditions such as X-ray transmittance and thickness as a mask material holding thin film.

Furthermore, the advantage of the present invention over other X-ray sensitivity enhancement methods is that it can be applied to most resists that have been used as photosensitive resists (including visible, ultraviolet, and deep ultraviolet resists). That's true. At present, chloromethylated polystyrene is a typical resist that can be used as an X-ray resist. However, if the amount of chlorine is increased to enhance the sensitivity of this resist, the adhesion to the silicon substrate decreases, making it unusable. In general, when sensitivity is increased, other important performances such as resolving power, gamma (contrast), developing performance, adhesion, and liquid storage stability must be sacrificed. However, when forming a layer containing a photosensitive material, by using the Higashi molecular film accumulation method, the layer containing the photosensitive material has good adhesion to the substrate, and the resolution is low because it is a uniform thin film. It becomes an excellent resist film, and by containing a transition metal, the sensitivity is improved by utilizing the fluorescence generated not only from the layer containing the fluorescent substance but also within the layer containing the photosensitive material. It has improved dramatically.

Furthermore, by forming the layer containing the fluorescent substance using the single-molecule accumulation method, the film thickness is small and the spread of the generated fluorescence is small, so there is no deterioration in resolution, and the photosensitive material layer It also has good adhesion with layers containing .

The present invention overturns conventional common sense and can enhance only the sensitivity while maintaining the performance of each resist, and is an extremely superior resist compared to conventional methods.

[Brief explanation of drawings]

FIG. 1(a) is a cross-sectional view of the resist of the present invention provided on a substrate, and FIG. 1(b) and (C) are schematic diagrams of a single molecule of the photosensitive material used in the resist of the present invention. , FIG. 1(d) is a schematic diagram of the chemical molecules of the fluorescent substance used in the resist of the present invention, and FIG. FIG. 3 is a diagram for explaining the lithography method. 1: Single molecule of photosensitive material (layer containing photosensitive material) 2: Parent group, 3: Hydrophobic group, 4: Photosensitive site, 5: Transition metal (or ion), 6: Single molecule of fluorescent substance Molecule (layer containing fluorescent substance) 7: Substrate (carrier), 8: Water tank, 9: Water phase IO = partition plate Eye: Substrate (carrier) 12: Frame
13: Surface pressure paper, 14: Suspension thread
15: Surface pressure needle 16 2 control circuit system I7: Carrier upper and lower arms 18: Groove 19: X-ray source 20: Mask frame 21: Mask pattern 22:
Mask holding thin film 23: Substrate (carrier) 24: Layer containing photosensitive material (resist) 25: Characterized by fluorescent substance

Claims (2)

[Claims] (1) comprising a layer containing a photosensitive material that is sensitized to irradiation energy and a layer containing a fluorescent substance that generates fluorescent rays that sensitize the photosensitive material when exposed to the irradiation energy; A resist for lithography, wherein the layer containing the photosensitive material and the layer containing the fluorescent substance each include a monomolecular film of an organic compound containing a photosensitive material and a fluorescent substance, or a cumulative film thereof. (2) The resist for lithography according to claim 1, wherein the layer containing the photosensitive material and/or the layer containing the fluorescent substance contains a transition metal.