JP2001176788A - Pattern-forming method and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antireflection film having satisfactory antireflection effects and a high etching selective ratio with respect to resist. SOLUTION: A resist film is formed on a treating substrate with a coating- type inorganic antireflection film containing Si-N bond, Si-O bond or Si-H bond in-between. Then, exposure with a light bean of 200 nm or shorter is carried out to form a resist pattern. Then, the base substrate is etched with a mask of the resist pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a pattern using an optical projection exposure apparatus and a method of manufacturing a semiconductor device using the above technique, and is particularly suitable for a method of manufacturing a MOS semiconductor device.

[0002]

2. Description of the Related Art In the manufacture of semiconductor devices, a photolithography technique using far ultraviolet light, such as a KrF excimer laser having a wavelength of 248 nm, is used as a technique for forming a pattern that achieves both high integration of circuits and throughput. According to this method, light that has passed through a mask pattern is projected and exposed on a resist film formed on a substrate to be processed via a projection optical system, and a predetermined developing process is performed on the light to form a pattern.
In order to improve the resolution of the transfer pattern, the wavelength of the light source has been shortened, and introduction of an ArF excimer laser having a wavelength of 193 nm is being studied.

In such an optical lithography technique, multiple interference of light in the resist film occurs due to light reflection at an interface between the substrate to be processed and the resist film. For this reason, there has been a problem that a change in the resist film thickness causes a dimensional change in the pattern after development.

[0004] In order to reduce the above-mentioned problems, it has been studied to insert various antireflection films between the substrate and the resist film. As the anti-reflection film, an inorganic CVD anti-reflection film (BARL: Bottom) using an inorganic film such as a SiON film formed by a chemical vapor deposition (CVD) method or the like.
Anti Reflective Layer) method is known. Further, a method using a coating organic film as the antireflection film (B)
The ARC method (Bottom Anti Reflective Coating) is also used. In addition, a method of forming a polyphenylsilsesquioxane film as an antireflection film by spin coating on the substrate to be processed has been studied.

[0005] Various conventional resist pattern forming methods including the above method are discussed in, for example, "Resist Materials and Process Techniques" published by Technical Information Association.

[0006]

The above-mentioned CVD-SiON
In the method of forming an antireflection film using a film, it becomes difficult to form a film with a uniform film thickness on a wafer as the diameter of the wafer increases. There is also a problem that an expensive film forming apparatus is required.

On the other hand, in the BARC method using an organic film, a resist pattern formed by exposure and development
Since the resist pattern deteriorates when the ARC film is dry-etched, it is necessary to increase the thickness of the resist. In this case, there is a problem that a sufficient resolution cannot be obtained or the pattern falls.

Further, the material process using the above-mentioned polyphenylsilsesquioxane has a problem that foreign matters such as fine particles are easily generated at the time of peeling, since it is an organic Si-based material.

An object of the present invention is to solve the above-mentioned problems and to provide a pattern forming method using an antireflection film which is excellent in uniformity and process latitude and generates little foreign matter.

[0010]

Means for achieving the above object will be described with reference to FIG. S on base substrate 103
After forming an inorganic thin film 101 by spin coating using an inorganic polymer or an inorganic oligomer containing at least one of an iH bond or a Si-N bond, a resist film 102 is formed on the inorganic thin film (FIG. 1a). ), Wavelength 200
The resist film is selectively exposed to a predetermined region 105 using light 104 of nm or less (FIG. 1B), and then developed to selectively remove the exposed portion 105 or the unexposed portion of the film to form a pattern 106. (FIG. 1c).

Next, the pattern is transferred to the inorganic thin film using the pattern as an etching mask to form an inorganic thin film pattern 107 (FIG. 1d), and the base substrate is etched using the inorganic thin film and the resist film pattern. A base pattern 108 is formed (FIG. 1e), and thereafter,
The desired pattern 109 is removed by removing the resist pattern.
(FIG. 1f).

Examples of the inorganic spin coating material having at least one of the above Si—H bond and Si—N bond include polymers, oligomers, copolymers such as hydroxysiloxazan, hydroxysilazane and hydrosilsesquioxane, or these. Can be used. In particular, when a compound having the chemical structure represented by the general formula of Chemical Formula 1 or an inorganic mixture containing the above compound is used, more excellent results can be obtained.

[0013]

Embedded image

Here, R in the above chemical formula 1 represents either a hydrogen group, a hydroxyl group or an inorganic base, and the functional groups do not need to be the same.

The pattern transfer from the organic resist to the inorganic film and from the inorganic film to the substrate can be performed continuously in the same etching apparatus.

In the removal of the inorganic antireflection film formed by this method, mechanical polishing, chemical mechanical polishing (CMP), a wet process using diluted hydrofluoric acid or a strong alkali, or dry etching using a fluorine gas system or the like is used. Etc. can be used.

Further, a wiring material or the like is buried in the groove of the base substrate formed by etching, and then the surface thereof is polished to flatten the surface and simultaneously remove the inorganic film, or after flattening the wiring material, The inorganic thin film may be removed.

The present method is characterized in that an antireflection film is formed using a coating type inorganic oligomer or polymer. When an inorganic anti-reflection film is formed using an inorganic polymer or an inorganic oligomer containing at least one of a Si-H bond and a Si-N bond, a resist pattern and the anti-reflection film are formed by using a CF-based etching gas or the like. It is easy to obtain an etching selectivity between the two. Therefore, the thickness of the resist for pattern formation can be reduced as compared with the case where BARC is used. Reducing the thickness of the resist film contributes to improvement in resolution and process latitude.

The thickness of the inorganic film is preferably 30 nm or more and 500 nm or less in order to form the film uniformly by spin coating.

In this method, since a thin film is formed by spin coating, compared to the BARL method, (1) foreign substances are less likely to be generated during film formation, (2) no expensive apparatus is used, and (3)
There are advantages such as that it is easy to form a uniform film with a uniform film thickness on a flat large-diameter wafer. This is because the inorganic Si antireflection film formed using this method does not contain an organic component, and thus can reduce the generation of fine particles when peeled by a method such as a CMP method or a dry process. . For this reason, a pattern with less defects can be formed as compared with the method using an organic Si-based antireflection film formed of the phenylsilsesquioxane or the like.

Assuming that the difference between the complex refractive indices of the substrate and the resist is U1 and the sum of the complex refractive indices of the substrate and the resist is U2, the reflectance R of the interface between the underlying substrate and the resist is (│U1
| / | U2 |) squared. Many resists for vacuum ultraviolet exposure have an exposure wavelength of 50 μm / μm film thickness.
% And a refractive index of about 1.5. By selecting a material having a refractive index substantially equal to that of these resists and a large absorption for the antireflection film, the reflectance R can be reduced.

Also, by using the interference in the anti-reflection film, the R of the formed anti-reflection film can be reduced. Due to the interference in the antireflection film, R of the antireflection film is also a function of the thickness of the antireflection film. for that reason,
By forming an antireflection film having an optimum thickness, an excellent antireflection effect can be obtained.

In general, it is desirable that the antireflection film has an absorption of 2 / μm or more for the wavelength to be exposed. Therefore, this material system is excellent in optical performance as an antireflection material at an exposure wavelength of 200 nm or less. Further, it is also possible to optimize according to the optical parameters of the resist by changing the composition.

The Si—H bond or Si
The -N bond shows strong light absorption for light having a wavelength of 200 nm or less. FIG. 5 shows the measurement results of light absorption of polyhydrosilazane. As is clear from FIG. 5, the absorption sharply increases from a wavelength of 220 nm, and at a wavelength of 200 nm, the absorption becomes 15 / μm.
The above shows a very strong absorption. Therefore, by using these materials, the present method is suitable for combination with a projection exposure apparatus having a light source having an exposure wavelength of 200 nm or less. As an applied light source, it is desirable to use an ArF excimer laser and an F2 excimer laser.

The reaction mechanism of the present invention will be described for the case of polyhydrosiloxazan. When polyhydrosiloxane is spin-coated and heat is applied, Si-H groups having high reaction activity react with water molecules or oxygen molecules in the air to generate silanol bonds. Since the silanol bond is relatively unstable, it is dehydrated by heat or the like to form a Si—O bond. Particularly in the presence of an acid, the above reaction proceeds extremely quickly. Therefore, in the above-mentioned process, the presence of oxygen molecules and water molecules in the air and the control of the acid in the film are important in controlling the reaction.

When the process temperature is set to 200 ° C. or higher, the Si—H bond is broken, and reacts with oxygen molecules or moisture in the air to form a Si—O bond. Therefore, there is an advantage that the ratio between the Si—H bond and the Si—O bond can be easily controlled by a process.

The above polyhydrosiloxazan has a wavelength of 220
Although it is transparent to light with a wavelength of 200 nm or more, it absorbs light with a wavelength of 200 nm or less, and hardly transmits light at an ArF excimer laser wavelength (193 nm) (absorption coefficient = 15 / μm). . On the other hand, since the Si—O bond is transparent to the ArF excimer laser, it is possible to change the absorptance by changing the temperature of the heat treatment.

Further, the above polyhydrosiloxazan is S
The refractive index can be controlled by changing the ratio between the i-O bond and the Si-N bond. From the above Si-H bond,
Since the chemical change that produces the bond is accompanied by a change in the refractive index, the refractive index can also be controlled by the process.

In summary, the use of the above-mentioned inorganic thin film can suppress the influence of dimensional fluctuation due to reflection from the underlying substrate and multiple interference in the resist film. The absorptivity and the refractive index of the film can be optimized according to the thickness of the inorganic thin film and the thickness of the upper resist.

In the above description, the case of polyhydrosiloxazane has been described. However, a coating inorganic material containing a Si—N bond, a Si—H bond, a Si—O bond or the like within a range not changing the gist of the present invention. All materials can be used. It goes without saying that other bonds than those described above may be included in a range that does not change the gist of the present invention.

In order to enhance the adhesion between the photosensitive material and the substrate, it is preferable to perform a surface treatment on the underlying substrate or to add a material for improving the adhesion to the photosensitive material. Furthermore, introducing and mixing a compound that generates radicals by irradiating far ultraviolet light into the resist is effective for speeding up and stabilizing the thermal process.

In particular, when the upper resist is a chemically amplified resist, by adding an acid generator or an acidic material, the thermal process of the inorganic film is accelerated, and at the same time, the bottom of the resist pattern is formed. Etc. can be solved.

After the development, the substrate is heated to 200 ° C. or more, exposed to oxygen plasma by oxygen ashing, oxygen reactive ion etching, or the like,
By irradiating light of not more than 00 nm, S
By promoting the formation of iO ₂ , it is possible to improve the film properties such as dry etching resistance and hygroscopicity.

On the other hand, by heating in a nitrogen atmosphere or a reducing atmosphere, the antireflection film pattern can be made into silicon nitride, thereby improving the film properties such as dry etching resistance and moisture absorption. be able to.

The formed SiON pattern may provide a high selectivity with respect to the resist pattern. When the underlying polysilicon or the like is dry-etched using the SiO _x N _y pattern as a mask, a higher selectivity may be obtained than when a conventional resist made of an organic material is used as a mask.

The pattern forming method of the present invention can be applied to the pattern forming step using an organic resist.
As a result, a pattern with excellent dimensional control can be formed.

The pattern forming method of the present invention can be applied to various semiconductor integrated circuits (L
SI). In the case of a MOS semiconductor, the method of the present invention can be used in various pattern forming steps such as pattern formation of a gate material such as amorphous silicon or metal, formation of a damascene Si groove, and formation of a through hole.

The pattern of the inorganic layer formed in the method of the present invention may be removed after the underlayer processing. However, if the pattern is left in the semiconductor device without being removed, the manufacturing process is further simplified. In this case, there are advantages that the dielectric constant is smaller than that of a CVD silicon oxide film or the like, and that the pattern does not include an organic component. Also, for reasons such as the structure of the device,
It can be used in combination with a normal CVD film or an organic polyimide film. The present invention has the advantage that throughput and yield are good because the process is simple.

[0039]

(Example 1) Polyhydrosilsesquioxane and polyhydrosilazane were mixed at a ratio of 2: 3, and a 10% by weight solution of the above mixture in ethylcellosolve was prepared at 2000 rpm for 60 seconds. With 7 on the surface
Spin coating was performed on a Si substrate having a step of about 0 nm. Thereafter, heat treatment was performed at 120 ° C. for 3 minutes to form an antireflection film having a thickness of 50 nm. The transmittance of the antireflection film to ArF excimer laser light was 5% at a thickness of about 0.1 μm.

On the antireflection film, a positive resist film for ArF exposure is formed by spin coating, and various patterns having a size of 0.13 μm to 1 μm are measured using an ArF excimer laser exposure apparatus (aperture ratio NA = 0.60). Was exposed.

As a result of observing the pattern exposure portion with a scanning electron microscope, it was found that the laser exposure amount was 22 mJ / cm ² .
It was confirmed that a pattern having a dimension of 0.13 μm was formed. Also, when the dimensions of the pattern formed above were measured by dimension measurement SEM, the pattern could be formed with a dimensional accuracy within 10% of the desired dimension even at the stepped portion. As a result, the effect of preventing reflection of the inorganic thin film from the substrate interface by the present method was also confirmed.

(Embodiment 2) Next, an example in which the present invention is applied to a gate processing step of a MOS integrated circuit will be described with reference to FIG. A film thickness of 20 on the thermally oxidized Si substrate 201;
A 0 nm poly-Si layer 202 / WSi layer 203 was formed by a CVD method. A xylene solution of polyhydrosiloxazane (concentration 15% by weight) was applied onto the membrane at 2000 rpm.
The film was spin-coated under the conditions of m and 60 seconds, and then heat-treated at 200 ° C. for 1 minute to form an antireflection film 204 having a thickness of 70 nm.

At this time, the reflectivity of the film for light having a wavelength of 193 nm was about 3%. In addition, a uniform thin film having a thickness of 30 to 1000 nm could be formed by spin coating of polyhydrosiloxazan.

Next, a 300-nm thick positive resist film 205 for ArF exposure was formed by spin coating. An ArF excimer laser exposure apparatus (NA = 0.6
After exposing various patterns having a size of 0.11 μm to 1 μm using the method (0), the pattern exposed portion was removed by a predetermined heat treatment and wet development to form a pattern 206.
For a laser irradiation dose of 20 mJ / cm ² , the minimum dimension is 0.1 mm.
The formation of the 13 μm pattern was confirmed by a scanning electron microscope. When a periodic phase shift mask was used, a pattern having a size of 70 nm with a period of 200 nm could be formed.

Next, the above resist pattern was converted to C ₂ F ₆ +
Using an etching gas of O ₂ + He, the film was transferred to the polyhydrosiloxazan film by dry etching. At this time, the etching rate of the polyhydrosiloxazan film with respect to the ArF exposure resist was about three times.

Further, the underlying poly-Si film was dry-etched using the above pattern as a mask with an etching gas of Cl ₂ + O ₂ to form a pattern 207. On this occasion,
The anti-reflection film pattern also plays a role as a hard mask, enabling a small dimensional change to be transferred to the underlying poly-Si film. In the case of both of the above-described pattern transfer, when the ratio of the O ₂ etching gas added for improving the high selectivity and the rectangularity of the processed shape is increased, the edge roughness of the processed pattern after etching tends to increase. there were.

When the ArF exposure resist was removed by oxygen ashing, the antireflection film was also oxidized and changed to a relatively porous SiO ₂ film having a low density. Therefore, it could be easily peeled off by a chemical mechanical polishing (CMP) method. After the peeling, when the number of foreign substances was measured by a foreign substance inspection device, it was 0.8 wafers / 8 inch wafer.

In this embodiment, polyhydrosiloxane was used for the antireflection film, but the Si—H bond, the Si—N bond,
The material is not limited to the one shown in this embodiment as long as it can be spin-coated with an inorganic material having any of Si—O bonds and can obtain the same effect. When a silazane-based material is used, ammonia generated from a silazane bond may impair the resolution of the upper resist film, and therefore, it is necessary to optimize the heat treatment time according to the material.

Although chlorine gas is used as an etching gas, any gas used as an etching gas for polysilicon can be used without being restricted to this embodiment. For example, a bromine-based gas such as bromic acid (+ oxygen) or a fluorine-based gas may be used. Further, in the same manner as in the present embodiment, it is possible to process a polymetal silicon gate, a metal gate, or a Si oxide film, a Si nitride film, or the like which serves as a cap material for these gates.

According to the present example, a fine gate pattern could be formed using the coating type inorganic antireflection film. The inorganic antireflection film was excellent in the etching selectivity with respect to the upper resist film, and the generation of fine particles due to peeling was reduced.

(Embodiment 3) Next, an embodiment in which the present invention is applied to a dual damascene process used in a wiring process for manufacturing a semiconductor device will be described with reference to FIG.

Wiring pattern 3 filled with insulating material between wirings
A silicon nitride film 302 having a thickness of 50 nm was formed on a semiconductor device substrate having 01 on the surface, and a SiO ₂ film 303 having a thickness of 700 nm was formed thereon by CVD. A 70 nm-thick polyhydrosiloxazan film 304 was formed on the SiO ₂ film by a spin coating method (FIG. 3A).

Next, a positive resist film 305 for ArF exposure having a thickness of 400 nm was formed by spin coating. ArF
A resist hole pattern 306 having a diameter of 0.15 μm and aligned on the Cu wiring pattern was formed by a known lithography process using an exposure apparatus (NA = 0.6) (FIG. 3B).

Next, the resist hole pattern 306 is formed.
, The polyhydrosiloxane film 304 and the underlying SiO ₂ film 303 were etched using a CF-based etching gas. Further, the remaining resist pattern was removed by oxygen ashing (FIG. 3C).

Next, a 350 nm-thick positive resist film 307 for ArF exposure was applied again on the polyhydrosiloxazan film while leaving the film (FIG. 3d). Using an ArF exposure apparatus, a wiring pattern having a width of 0.15 μm was exposed, and a resist pattern 308 having a wiring portion shape was formed on the hole pattern processed in the above process (FIG. 3).
e).

Using the wiring pattern, the base SiO
_{The second} film 303 was etched by a depth of 300 nm. Thereafter, the resist film for ArF exposure was removed by oxygen ashing (FIG. 3F). The silicon nitride film and the polyhydrosiloxazan antireflection film at the bottom of the hole were simultaneously removed by dry etching. For this reason, the steps of the present method were very simple.

The above-mentioned hole and the wiring groove are integrated with Si.
Cu was buried in the groove portion of the O ₂ workpiece 309 by plating, and thereafter, excess Cu existing on the substrate surface other than the hole and the wiring groove was removed by CMP. Thus, a Cu wiring 310 was formed (FIG. 3G).

In the above embodiment, the separation of the polyhydrosiloxane film 304 was performed by using the silicon nitride film 3 at the bottom.
Although the removal is performed at the same time as the removal of 02, the peeling procedure and method can be changed without departing from the spirit of the present invention. For example, the polyhydrosiloxazane film 304 is made of C
When the u film 310 is subjected to CMP, it can be peeled off at the same time. Further, when strong oxygen ashing is applied to the polyhydrosiloxane film 304, the film quality becomes porous, and when the CMP method is applied, the selectivity with respect to the underlying SiO ₂ film can be improved.

However, in this embodiment, the process was simple because the dry etching conditions were set so that the polyhydrosiloxane film and the silicon nitride film were simultaneously removed.

In the above embodiment, the same polyhydrosiloxane film is commonly used as an anti-reflection film in the two resist exposure steps, so that the steps are simplified. May be formed with an anti-reflection film. In the case of forming the pattern, it is desirable to use an ArF exposure resist in which the adhesion, the resolution, the process latitude and the like are optimized for the pattern to be formed.

When a material containing a Si—N bond is used,
By applying an oxygen ashing step or the like before forming the resist film, the adhesion can be improved.

According to the present embodiment, a wiring pattern can be formed by the dual damascene method using the present invention.

(Embodiment 4) Next, a method of manufacturing a MOS semiconductor device using the present invention will be described with reference to FIG. The following description is for the purpose of showing the relationship between the main steps of the MOS semiconductor device manufacturing process and the present invention, and therefore does not describe all the manufacturing steps.

(1) Formation of Element Isolation First, after a silicon nitride film 403 is formed on a silicon substrate 404, a resist pattern is formed on an active layer portion of a manufactured MOS integrated circuit by using substantially the same method as in the first embodiment. 4
01 was formed (FIG. 4a). Next, using this as a mask, the antireflection layer 402, the silicon nitride film 403, and the silicon substrate 404 were etched, and silicon oxide was embedded in the formed grooves. Next, a silicon nitride film is formed in a wide area portion of the groove by a normal method, and then the substrate surface is flattened by a CMP method.
Further, by removing the silicon nitride film, a so-called shallow trench isolation (S
GI) 405 to form an element isolation (FIG. 4b).

(2) Gate formation Next, after a predetermined well formation, gate insulation film formation, channel formation and the like are performed, a gate multilayer comprising a polysilicon film 406, a TiN film 407, and a W film 408 is formed on the gate insulation film. A film was formed, and a silicon nitride film 409 and a silicon oxide film 410 were further laminated.

A resist pattern 411 is formed on the laminated film using a method substantially similar to that of the second embodiment (FIG. 4C).
Using this as a mask, the silicon nitride film 409 and the silicon oxide film 410 were etched, and the underlying gate film was further etched to form a gate pattern 412 (FIG. 4D).

(3) Formation of Contact Hole Next, after predetermined ion implantation, formation of LDD sidewall 413, formation of salicide of source and drain portions, formation of an interlayer insulating film using silicon oxide, and planarization of the insulating film surface, A resist pattern 414 having an opening in a contact hole portion was formed by using a method substantially similar to that described above (FIG. 4E), and the interlayer insulating film was etched using this as a mask. After removing the resist pattern 414, the W plug 4
15 was buried and the surface was flattened to form a desired contact hole (FIG. 4f).

(4) Formation of Wiring Next, a Cu wiring (not shown) is formed thereon by the so-called dual damascene method using the method described in the third embodiment.
Was formed.

A MOS integrated circuit was manufactured using the above steps, and its operation was confirmed. MO manufactured according to this embodiment
The S integrated circuit has excellent uniformity in circuit dimensions and therefore has better performance than in the past, and the number of manufacturing steps is reduced as compared with the conventional manufacturing method, so that the manufacturing cost was also reduced.

Although not shown here, the pattern forming method according to the present invention uses the other components of the MOS semiconductor device,
For example, it can be used for processing capacitors in DRAMs and ferroelectric memories.

Although the example in which the present invention is applied to the basic pattern of the MOS LSI has been described above, the present invention is not limited to the above-described embodiment, and may be applied to other steps of the LSI or semiconductor devices of other types of materials, for example, a bipolar LSI. Or a fine structure such as an optoelectronic device such as a gallium arsenide semiconductor or a semiconductor laser. In that case, the material to be processed, the type of photosensitive material, the exposure method, the development method, the etching method, the gas, etc. are changed, and accordingly, the composition and processing conditions of the antireflection material according to the present invention are changed according to the present invention. It is desirable to optimize as long as the purpose is not deviated.

[0072]

As described above, according to the present invention, an antireflection film containing any one of a Si--H bond, a Si--N bond and a Si--O bond formed by spin coating on a substrate having a workpiece on its main surface. By performing a lithography step using the method, an antireflection film having an excellent antireflection effect and a high etching selectivity to a resist is provided. High resolution performance and
Excellent dimensional control is possible, and the performance of the LSI is improved, the manufacturing yield is improved, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a process in one embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a process in one embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a step in one embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a step in one embodiment of the present invention.

FIG. 5 is a measurement diagram showing the optical characteristics of the reflection film of the present invention.

[Explanation of symbols]

101: inorganic antireflection film, 102: resist film, 103
... Base substrate 104, light source 105, exposure unit 106
Resist pattern, 107: pattern after etching, 1
08: pattern after substrate etching, 109: pattern after resist removal, 201: silicon substrate, 202: poly S
i film, 203: WSi film, 204: inorganic antireflection film, 2
05: resist film, 206: resist pattern, 207
… Gate pattern, 301… wiring pattern, 302… silicon nitride film, 303… SiO2 film, 304…
Polyhydrosiloxane-coated inorganic antireflection film, 305
.., ArF exposure resist film, 306, resist hole pattern, 307, ArF exposure resist film, 308, resist wiring pattern, 309, SiO2 insulating film pattern, 310, Cu wiring pattern, 401, resist pattern, 402, inorganic reflection prevention Layer, 403: silicon nitride film, 404: silicon substrate, 405: shallow groove separation part, 40
6 ... polysilicon film, 407 ... titanium nitride film,
408: tungsten film, 409: silicon nitride film, 4
10: silicon oxide film, 411: resist pattern, 4
12 gate pattern, 413 LDD sidewall, 414 resist pattern, 415 tungsten plug.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/336

Claims (6)

[Claims] A first step of forming an inorganic thin film on a substrate to be processed by a spin coating method; a second step of forming a resist film on the inorganic thin film; A third step of exposing and developing the film to selectively remove the exposed portion or the film other than the exposed portion and forming a pattern, etching the inorganic thin film and the substrate to be processed using the pattern as a mask A pattern forming method, comprising: 2. A first step of forming an inorganic thin film containing at least one Si—N bond or Si—H bond on a substrate to be processed by a spin coating method, wherein a resist film is formed on the inorganic thin film. A second step of forming, selectively exposing the resist film using light having a wavelength of 200 nm or less, and developing and selectively removing the exposed portion or a film other than the exposed portion to form a pattern; 3. A pattern forming method, comprising: a third step, a fourth step of etching the inorganic thin film and the substrate to be processed using the pattern as a mask. 3. The pattern forming method according to claim 2, wherein in the third step, the light having a wavelength of 200 nm or less is an ArF excimer laser light or an F2 laser light. 4. The pattern forming method according to claim 2, wherein said inorganic thin film has an absorption of 2 / μm or more with respect to a wavelength to be exposed in the third step. 5. The pattern forming method according to claim 2, wherein the polymer or oligomer as a main component of the resist film is a compound having a chemical structure represented by Chemical Formula 1 or a mixture containing the compound. Embedded image Here, R in the above chemical formula represents any one of a hydrogen group, a hydroxyl group, and an inorganic base, and the functional groups need not be the same. 6. A semiconductor device manufactured by using any one of the pattern forming methods according to claim 1.