KR100563813B1 - Fabrication Method and Manufacture for a Photomask using Atomic Force Microscope Lithography - Google Patents

Abstract

The present invention is one of the next-generation exposure process mask cantilever tip of a contact atomic force microscope (NT-MDT) and metal titanium (Ti), chromium (Cr) / Quartz substrate or PBET / metal titanium (Ti), Provided are a method of manufacturing an optical mask including a first step using anodization with a chromium (Cr) / Quartz substrate and a second step of etching out protruding titanium oxide, and a mask manufactured at this time.

The present invention is characterized in that, as a transmissive exposure mask, a pattern size of several nm (40 nm or less) can be obtained compared to a conventional exposure photo mask.

Atomic Force Microscopy, Lithography, Masks, Cantilever Tips, Exposure Processes

Description

Fabrication Method and Manufacture for a Photomask using Atomic Force Microscope Lithography}             

1 is a cross-sectional view of a chrome mask fabricated using a conventional Electron Beam lithography technique.

2 is a process diagram showing an embodiment of a method of manufacturing a photo mask using an atomic force microscopy lithography technique according to the present invention

Figure 3 is a process diagram showing another embodiment of the manufacturing method of the photo mask using the atomic force microscopy lithography technique according to the present invention

4 is a schematic diagram illustrating a mechanism of an internuclear microscope lithography technique according to the present invention.

5 is a surface image of the surface roughness of titanium deposited in a real time process using a magnetron sputtering equipment (MS-2100) in the method according to the present invention using an atomic force microscope

6 is an image of a titanium surface after a lithography process using an atomic force microscope in the method according to the invention.                 

<Explanation of symbols for main parts of drawing>

10: glass quartz substrate 11: chromium thin film

12: thin metal film 13: PBET thin film

14 cantilever tip 15 metal / glass quartz substrate

The present invention relates to a method for manufacturing a transmissive exposure mask using a nuclear atomic microscope which performs nanolithography in a semiconductor related manufacturing process such as a semiconductor integrated circuit device, a TFT-LCD, and more particularly, to a mask produced at this time. By applying a predetermined voltage between the cantilever tip of the liver microscope and the substrate to form a water column between the tip and the substrate, the oxide layer material is grown on the substrate, and the oxide material thus formed is dried. It relates to a mask produced by the process of removing through etching or wet etching, and a manufacturing method at this time.

In general, photomasks related to the manufacture of semiconductor-related devices such as semiconductor integrated circuit devices and TFT-LCDs have a structure in which chromium is patterned on a transparent quartz glass substrate and includes the following processes.

For example, as shown in FIG. 1, after depositing the chromium thin film 11 on the transparent quartz glass substrate 10, a resist material is applied for the pattern of chromium.                         

Subsequently, the resist material is patterned to a size of several tens of nm using an electron beam drawing apparatus, and then the lower chromium thin film is processed by dry etching or wet etching.

Thereafter, the resist material is removed by washing or the like to obtain a pattern mask having a desired shape.

The recent semiconductor technology requires high integration of many devices while reducing the pattern size of the devices.

Therefore, in order to reduce the pattern size of the device, first, the implementation of the fine pattern in the exposure process is required.

In the conventional electron beam drawing apparatus, there are many difficulties in implementing a fine pattern as well as damaging the substrate by scattering of the electron beam, and the line width that can be implemented has also reached its limit near 30 nm.

Accordingly, the present invention has been made in view of the above, by providing a photomask manufacturing method capable of realizing a fine pattern up to a minimum of several nm beyond the limitation of realizing the fine line width of the existing electron beam drawing method, the pattern size of the mask In addition to significantly reducing the shape of the pattern can also be produced in a variety of shapes, and the purpose is to simplify the mask manufacturing process.

A method of fabricating a photomask using the internuclear microscope lithography technique of the present invention for achieving the above object comprises depositing a thin metal film of titanium or chromium on a transparent glass quartz substrate by sputtering, and using a cantilever tip using an atomic force microscope. Applying an electric field to the substrate of the thin film structure to form an oxide film of titanium oxide or chromium oxide material having a predetermined height and width on the substrate, and cleaning the resist material after etching the oxide material to obtain an ultra fine line width. And manufacturing a photo mask.

On the other hand, the photomask fabricated using the internuclear microscope lithography technique of the present invention for achieving the above object has a structure of a metal thin film of titanium or chromium on a glass quartz substrate, the titanium or chromium thin film on the substrate After the deposition, further comprising the step of depositing a PBET (Poly (3- (2-benzotriazoloethyl) thiophene) thin film thereon to have a two-layer thin film structure, wherein PBET (Poly (3- (2-benzotriazoloethyl) ) thiophene) material is coated by spin casting so that the film thickness is 2-18nm.

In addition, the thinner the thickness of the PBET thin film, the more smoothly the applied voltage flows, which has the advantage of easily forming oxides in the lithography process. Tetrachloroethane) is removed by solvent.

In addition, the step of forming an oxide film of titanium oxide or chromium oxide material using the atomic force microscope further comprises the step of adjusting the pattern size by adjusting the applied voltage.                         

In addition, the step of manufacturing the ultra-fine photo-width photo mask is characterized in that the size of the pattern can be implemented to 40 nm or less using an atomic force microscope.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

As shown in Figs. 2 and 3, the present invention is a thin film structure of a titanium or chromium metal thin film 12 on a glass quartz substrate 10 to fabricate a transmissive photo mask having an ultra fine pattern size of several nm. Deposit.

At this time, the deposition conditions of the titanium or chromium metal thin film material deposited using the magnetron sputter (MS-2100) are titanium 500 and chromium thin film DC 500W, process pressure 5mtorr and DC 100W, respectively, in the atmosphere of argon (Ar), an inert gas. The process pressure is 3 mtorr, and the deposited metal thin film has a thickness of 2-10 nm.

As described above, in the present invention, it is possible to reduce the contamination of the substrate by using the stuttering equipment during thin film deposition, and in particular, to lower the surface roughness value, which is an important factor in the lithography process for implementing the fine pattern of the atomic force microscope. have.

In the present invention, as can be seen in Figure 5 provides a surface roughness value of 1Å.                     

When an electric field of "-" and "+" is applied to a cantilever tip 14 and a substrate having a multilayer thin film structure using an atomic force microscope, oxides having a height (a few nm or less) and a width (a few tens of nm or less) of the substrate are applied. An oxide film of the material can be obtained.

In addition, the height and width of the oxide material generated during the lithography process using the atomic force microscope can be adjusted in the patine size according to the control of the applied voltage.

The lithography technique using the atomic force microscope provided by the present invention is described as follows.

As shown in FIG. 4, the following reaction occurs while forming a water column between the tip and the substrate by applying a voltage of several V between the cantilever tip (−) and the substrate (+) of the atomic force microscope. .

For substrates, M + xH ₂ O → MOx + 2xH ⁺ + 2Xe-

2H ₂ O → O 2 + 4H ⁺ + 4e-

For a _{tip, 2H 2 O + 2e → H} 2 + 2OH -

By this reaction, ion diffusion of OH- and O- onto the substrate occurs and eventually anodization occurs on the substrate to form an oxide of an oxide layer.

In FIG. 6, an atomic force microscope of an oxide material formed by an atomic force microscope at a humidity of 40-50% and a lithography speed of 3-10 m / sec by applying a voltage of 5-10 V is shown. The surface image of is shown.                     

Finally, the etching of the oxide material and the cleaning of the resist material may be performed to fabricate a photomask having a very fine line width.

As described above, the present invention can realize a fine pattern up to several nm (40 nm or less) without damaging the substrate by using an atomic force microscope in the lithography step of the semiconductor process, and also obtain a pattern image of various shapes. .

Therefore, there is an effect that can be used to produce a photo mask that can transfer a mask pattern image of several nm of various shapes in the exposure process to the substrate.

Claims (6)

Depositing a thin film structure of a titanium or chromium metal thin film on a transparent glass quartz substrate by sputtering, forming an oxide film of an oxide material using an atomic force microscope, and cleaning the resist material after etching the oxide material In the photomask fabrication method using an atomic force microscopy lithography technique comprising the step of manufacturing a photomask having a very fine line width, The forming of an oxide film of an oxide material using the atomic force microscope may include applying an electric field to the cantilever tip and the thin film structure substrate using an atomic force microscope to form an oxide film of an oxide material having a predetermined height and width on the substrate. A method of fabricating a photomask using atomic force microscopy lithography technology, characterized in that it comprises a step of forming. The atomic force microscope of claim 1, wherein the applied substrate further comprises depositing a metal thin film of titanium or chromium on a quartz glass substrate and then depositing a PBET thin film on the quartz glass substrate to have a two-layer thin film structure. Photomask manufacturing method using lithography technique. The method of claim 1, wherein the forming of the oxide film of the titanium oxide material or the chromium oxide material using the atomic force microscope further comprises the step of adjusting the pattern size by adjusting the applied voltage. Photomask manufacturing method using lithography technique. The method of claim 1, wherein, in the manufacturing of the photomask having the ultra fine line width, the size of the pattern may be implemented to 40 nm or less using an atomic force microscope. . A photomask fabricated using an atomic force microscopy lithography technique characterized by having a metal thin film (12) structure of a titanium thin film or a chromium thin film on a glass quartz substrate (10). 6. The photomask of claim 5, wherein the photomask has a two-layer thin film structure in which a PBET thin film 13 is stacked on a metal thin film 12 of a titanium thin film or a chromium thin film. Photo mask.

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