KR101067863B1 - Method for forming fine pattern - Google Patents

Abstract

The present invention relates to a method for forming a fine pattern, by depositing an oxide film on the hard mask layer pattern and performing a planarization etching process to remove a step, thereby forming an anti-reflection film to prevent uniformity and coating defect of the anti-reflection film to prevent semiconductor devices. Represents a technique for improving the degree of integration.

Description

Fine pattern formation method {METHOD FOR FORMING FINE PATTERN}

1A to 1F are cross-sectional views showing a fine pattern forming method according to the prior art.

2A and 2B are photographs showing a problem of the method for forming a fine pattern according to the prior art.

3A to 3G are cross-sectional views illustrating a method for forming a fine pattern according to the present invention.

The present invention relates to a method for forming a fine pattern, by depositing an oxide film on the hard mask layer pattern and performing a planarization etching process to remove a step, thereby forming an anti-reflection film to prevent uniformity and coating defect of the anti-reflection film to prevent semiconductor devices. Represents a technique for improving the degree of integration.

1A to 1F are cross-sectional views illustrating a fine pattern forming method according to the prior art.

Referring to FIG. 1A, after forming the first hard mask layer 20, the first anti-reflection film 30, and the first photoresist film 40 on the semiconductor substrate 10, the first exposure mask 50 is used. To perform the primary exposure process.

Referring to FIG. 1B, the exposed first photosensitive film 40 is developed to form a first photosensitive film pattern 45.

Referring to FIG. 1C, after etching the first anti-reflection film 30 and the first hard mask layer 20 using the first photoresist pattern 45 as an etching mask, the first anti-reflection film 30 is removed and the first hard film is removed. The mask layer pattern 25 is formed.

Here, the first hard mask layer pattern 20 is preferably in the form of a line or space having a line width of 3: 1.

Referring to FIG. 1D, after forming the second anti-reflection film 35 and the second photosensitive film 60 on the semiconductor substrate 10 including the first hard mask layer pattern 25, the second exposure mask 70 is formed. To perform the secondary exposure process.

Here, the second anti-reflection film 35 is not uniformly formed due to the step of the first hard mask layer pattern 25.

Referring to FIG. 1E, the exposed second photosensitive film 60 is developed to form a second photosensitive film pattern 65.

In this case, the second photoresist layer pattern 65 may be formed to partially expose the line region of the first hard mask layer pattern 25.

Referring to FIG. 1F, the second anti-reflection film 35 and the first hard mask layer pattern 25 are etched using the second photoresist pattern 65 as a mask to form a second hard mask layer pattern 80. The second anti-reflection film 35 and the second photosensitive film pattern 65 are removed.

At this time, the second hard mask layer pattern 80 is preferably formed in the form of a line or space pattern having a line width of 1: 1.

2A and 2B are photographs showing a problem of the method for forming a fine pattern according to the prior art.

Referring to FIG. 2A, the TEM (Transmission Electron Microscope) photograph showing a poor coating uniformity of the anti-reflection film 35 according to the thickness of the hard mask layer 25. The thicker the hard mask layer 25 is, the pattern is. It can be seen that the difference in the thickness of the antireflection film 35 of the valley and the floor portion of the large.

Referring to FIG. 2B, it shows a line or space pattern formed by performing a double exposure process, and it can be seen that the line width of the edge portion of the line pattern is not uniform due to the poor coating of the anti-reflection film.

In the above-described fine pattern forming method according to the prior art, when the antireflection film is coated on the hard mask layer pattern having a 3: 1 line or space shape, the coating of the antireflection film is not uniformly formed due to the step between the line area and the space area. There is a problem that can not control the diffuse reflection of the lower anti-reflection film. As a result, the uniformity of the second anti-reflection film formed during the subsequent process may show a greater difference, resulting in poor coating.

In order to solve the above problems, by depositing an oxide film on the hard mask layer pattern and performing a planarization etching process to remove the step, an anti-reflection film is formed to prevent uniformity and coating defect of the anti-reflection film to improve the integration degree of the semiconductor device. It is an object to provide a technique for improving.

The fine pattern forming method according to the present invention

Forming an oxide film on the surface of the semiconductor substrate provided with the first hard mask layer pattern to planarize it;

Forming an anti-reflection film and a photoresist film on the oxide film;

After the exposure and development processes are performed to form a photoresist pattern, the antireflection film, the oxide film, and the first hard mask layer pattern are etched using the photoresist pattern as a mask to form a second hard mask layer pattern, and then the photoresist pattern and the antireflection film Steps to remove

Characterized in that it comprises a.

Hereinafter, with reference to the accompanying drawings an embodiment of the present invention will be described in detail.

3A to 3G are cross-sectional views illustrating a method for forming a fine pattern according to the present invention.

Referring to FIG. 3A, the first hard mask layer 110, the first anti-reflection film 120, and the first photoresist film 130 are sequentially formed on the semiconductor substrate 100, and then the first exposure mask 140 is formed. To perform the primary exposure process.

3B and 3C, the exposed first photoresist layer 130 is developed to form a first photoresist layer pattern 135, and the first anti-reflection layer 120 and the first photoresist layer pattern 135 are masked. 1 After the hard mask layer 110 is etched, the first photoresist layer pattern 135 and the first anti-reflection layer 120 are removed to form the first hard mask layer pattern 115.

Here, the first hard mask layer pattern 115 may be formed in a line or space shape having a line width of 3: 1.

Referring to FIG. 3D, an oxide film 150 is formed on the entire surface of the semiconductor substrate 100 including the first hard mask layer pattern 115, and then a planarization etching process is performed.

Here, the oxide film 150 is preferably formed of SiO ₂ , Boro-Phospho-Silicate Glass (BPSG) and Phospho-Silicata Glass (PSG) of 500 to 2500 Pa.

Referring to FIG. 3E, after forming the second anti-reflection film 160 and the second photoresist film 170 on the planarized oxide film 150, the second exposure process is performed using the second exposure mask 180.

Here, the second anti-reflection film 160 may be formed to a thickness of 250 to 400 kPa, and the second photoresist film 170 may be formed to a thickness of 800 to 2500 kPa.

Referring to FIG. 3F, the exposed second photoresist film 170 is developed to form a second photoresist pattern (not shown), and then the second anti-reflection film 160 and the oxide film are formed using the second photoresist pattern (not shown) as a mask. The line region of the 150 and the first hard mask layer pattern 115 is etched, and the second photoresist layer pattern (not shown), the second anti-reflective layer 160, and the oxide layer 150 are removed to remove the second hard mask layer pattern ( 190).

In this case, the removal process of the second photoresist layer pattern (not shown), the second anti-reflection layer 160 and the oxide layer 150 may be performed by performing a dry or wet etching process.

Referring to FIG. 3G, since the oxide layer 150 between the second hard mask layer patterns 190 is not completely removed, the oxide layer 150 is completely removed by performing a dry or wet etching process.

Here, since the second hard mask layer pattern 190 is formed of a nitride film or an oxynitride film and has an etching selectivity with respect to the oxide film 150, the oxide film 150 may be completely removed.

In addition, the second hard mask layer pattern 190 may be formed in a line or space having a line width of 1: 1.

In the method of forming a fine pattern according to the present invention, an oxide film is deposited on a hard mask layer pattern and a planar etching process is performed to remove a step, thereby forming an antireflection film to prevent uniformity and coating defect of the antireflection film, thereby preventing integration of semiconductor devices. Has the effect of improving.

In addition, a preferred embodiment of the present invention is for the purpose of illustration, those skilled in the art will be able to various modifications, changes, substitutions and additions through the spirit and scope of the appended claims, such modifications and changes are the following claims It should be seen as being in scope.

Claims (9)

Forming an oxide film on the surface of the semiconductor substrate provided with the first hard mask layer pattern to planarize it; Forming an anti-reflection film and a photoresist film on the oxide film; And After the exposure and development processes are performed to form a photoresist pattern, the antireflection film, the oxide film, and the first hard mask layer pattern are etched using the photoresist pattern as a mask to form a second hard mask layer pattern, and then the photoresist pattern and the antireflection film Removing; Fine pattern forming method comprising a. Claim 2 has been abandoned due to the setting registration fee. The method of claim 1, The first hard mask layer pattern is a fine pattern forming method, characterized in that the line or space pattern having a line width of 3: 1. Claim 3 was abandoned when the setup registration fee was paid. The method of claim 1, The oxide film is a fine pattern forming method, characterized in that formed to a thickness of 500 to 2500Å. Claim 4 was abandoned when the registration fee was paid. The method of claim 1, Claim 5 was abandoned upon payment of a set-up fee. The method of claim 1, The anti-reflection film is a fine pattern forming method, characterized in that formed in a thickness of 250 to 400Å. Claim 6 was abandoned when the registration fee was paid. The method of claim 1, The photosensitive film is a fine pattern forming method, characterized in that formed in a thickness of 800 to 2500Å. Claim 7 was abandoned upon payment of a set-up fee. The method of claim 1, After removing the photoresist pattern and the anti-reflection film The method of forming a fine pattern further comprising the step of removing the oxide film. Claim 8 was abandoned when the registration fee was paid. The method of claim 7, wherein The oxide film removing process is performed by performing a dry or wet etching process. Claim 9 was abandoned upon payment of a set-up fee. The second hard mask layer pattern is a fine pattern forming method, characterized in that the line or space pattern having a line width of 1: 1.

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